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A-Z listingplugin-autotooltip__plain plugin-autotooltip_bigA-Z listing

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# A-Z listing (archived)

This is an older, partial A-Z listing intended for search engines and indexing web-bots only. Last updated : Sept 2021 For an up-to-date list see A-Z listingplugin-autotooltip__plain plugin-autotooltip_bigA-Z listingThis is an alphabetical index of all content pages. in the Main Menu

"“Abracadabra is of unknown origin, and its first occurrence is in the second century works of Serenus Sammonicus, according to the Oxford English Dictionary. Several folk etymologies are associated with the word: from phrases in Hebrew that me…

Acamprosateplugin-autotooltip__plain plugin-autotooltip_bigAcamprosate

Acamprosate ( C5H11NO4S ) also known by the brand name Campral™, is a widely used drug used for treating alcohol dependence. It's now an over-the-counter medicine.

It's thought to stabilize chemical signalling in the brain that would otherwise be disrupted…

Acrocyanosisplugin-autotooltip__plain plugin-autotooltip_bigAcrocyanosis

Acrocyanosis is persistent blue-ish discolouration of the extremities, most commonly in the hands, feet, nose and ears. Sometimes with a cold and sweaty feel to the skin. In the benign form (called Primary Acrocyanosis) which is the most common, there are…

Acupunctureplugin-autotooltip__plain plugin-autotooltip_bigAcupuncture

Acupuncture, as a treatment for a wide range of diseases and conditions, has been practiced for more than 2,000 years.

Proponents say that it's not only effective, but, in contrast with drug treatments, it has very few deleterious side-effects.

Detractors…

Attention-Deficit / Hyperactivity Disorder (ADHD)plugin-autotooltip__plain plugin-autotooltip_bigAttention-Deficit / Hyperactivity Disorder (ADHD)

Attention Deficit Hyperactivity Disorder (ADHD) is a neuro-developmental mental disorder. It's characterized by problems in paying attention, excessive activity, or difficulty in controlling behavior (typically not appr…

"An adipose eyelid is a transparent eyelid found in some species of fish, that covers some or all of the eye. They are most commonly found on deep sea (benthic) fish, but can also be seen on non-benthic fish. Fish with this feature include milkfi…

Evolution of ageingplugin-autotooltip__plain plugin-autotooltip_bigEvolution of ageing

Evolutionary scientists have been trying to form a consolidated theory of ageing since the 1890's.

"Enquiry into the evolution of ageing aims to explain why a detrimental process such as ageing would evolve, and why there is so much variability in…

Alice in Wonderland Syndromeplugin-autotooltip__plain plugin-autotooltip_bigAlice in Wonderland Syndrome

'Alice in Wonderland Syndrome' (AiWS) (a.k.a. Todd's syndrome or dysmetropsia) is a neuropsychological disorder in which patients experience visual* distortions - so that surrounding objects can appear larger or smaller (or nearer of furthe…

Albanian language originsplugin-autotooltip__plain plugin-autotooltip_bigAlbanian language origins

The origin of the modern-day Albanian language is unknown.

"[...] its still-unknown origin has long been a matter of dispute among linguists and historians. Albanian is considered to be the descendant of one of the Paleo-Balkan

Alcohol intoxicationplugin-autotooltip__plain plugin-autotooltip_bigAlcohol intoxication

"Despite the fact that alcohol has been used and misused for hundreds of years, the mechanism of action of this simple molecule remains the subject of study. Alcohol use results in diverse behavioral effects, including intoxication, cognitive impa…

Alcohol and the cardiovascular systemplugin-autotooltip__plain plugin-autotooltip_bigAlcohol and the cardiovascular system

"Light-to-moderate drinkers tend to display an overall better cardiovascular health and longevity compared with abstainers or heavy drinkers (Klatsky et al., 1981; Maskarinec et al., 1998; Gaziano et al., 2000; Maraldi et al., 200…

Alcohol and body weightplugin-autotooltip__plain plugin-autotooltip_bigAlcohol and body weight

Despite research over several decades - some involving more than 100,000 subjects - it's still unknown whether alcohol can (in general) cause body-weight gain.

Although alcohol is caloric - at around 7 calories per gram - it also increases meta…

Ales Stenar (stones)plugin-autotooltip__plain plugin-autotooltip_bigAles Stenar (stones)

"Ales stenar (Stones) is Sweden's largest preserved “ship setting” - stones set in the layout of a ship. We do not know for certain what function the stones have had through the ages, or what the ship setting symbolised for the people who created …

Allais effectplugin-autotooltip__plain plugin-autotooltip_bigAllais effect

Note: This item is currently under review in 'proposed content' section

"“The Allais effect is the alleged anomalous behavior of pendulums or gravimeters which is sometimes purportedly observed during a solar eclipse. The effect was first reported as a…

Alpha effectplugin-autotooltip__plain plugin-autotooltip_bigAlpha effect

The Alpha Effect was first described by William P. Jencks and Joan Carriuolo in 1960. It refers to the increased 'nucleophilicity' of a molecule (i.e. the tendency for molecules or ions to donate a pair of electrons to form a chemical bond) due to the pre…

Alzheimer's diseaseplugin-autotooltip__plain plugin-autotooltip_bigAlzheimer's disease

"Alzheimer’s disease is a chronic progressive neuro-degenerative disorder characterised by three primary groups of symptoms. The first group (cognitive dysfunction) includes memory loss, language difficulties, and executive dysfunction (that is, lo…

Amoeboid movementplugin-autotooltip__plain plugin-autotooltip_bigAmoeboid movement

Amoeboid locomotion is the usual mode of movement in adherent (i.e. sticky) eukaryotic cells - e.g. amoebas, slime moulds, leukocytes and sarcomas etc etc. It also features in biological processes such as embryonic development, wound healing, and canc…

Ancient Macedonian languageplugin-autotooltip__plain plugin-autotooltip_bigAncient Macedonian language

Ancient Macedonian was spoken in the kingdom of Macedonia during the 1st millennium BC and belongs to the Indo-European language family.

Its origins are disputed.

"“The origins of the ancient Macedonian language are currently debated. It …

Anemonefish Symbiosisplugin-autotooltip__plain plugin-autotooltip_bigAnemonefish Symbiosis

The Orange clownfish - Amphiprion percula - (also known as the Percula clownfish and Clown anemonefish), is widely known as a popular aquarium fish. Like other clownfishes (also known as Anemonefishes), it often lives in association with sea anemo…

Ankylosing Spondylitisplugin-autotooltip__plain plugin-autotooltip_bigAnkylosing Spondylitis

"“Ankylosing spondylitis (AS) is a type of arthritis that affects the spine. AS often involves redness, heat, swelling, and pain in the spine or in the joint where the bottom of the spine (sacrum) joins the pelvic bone (ilium).

Anorexia Nervosaplugin-autotooltip__plain plugin-autotooltip_bigAnorexia Nervosa

Anorexia Nervosa (AN) is an eating disorder which currently affects around 3 million people per year.

"Anorexia nervosa (AN) is a serious mental illness categorized by a failure to maintain a minimally normal weight, a fear of gaining weight or becom…

Anorthsitesplugin-autotooltip__plain plugin-autotooltip_bigAnorthsites

Anorthsites are coarse-grained, lightweight volcanic rocks thought to have been formed between 1 and 2 billion years ago. They are mainly composed of 'Plagioclase feldspar' - around 90% CaAl2Si2O8 and 10% NaAlSi3O8

They were first dicovered in Norther…

Antibiotic Growth Promotersplugin-autotooltip__plain plugin-autotooltip_bigAntibiotic Growth Promoters

Antibiotic Growth Promoters (AGPs) were first licenced for use in farm animals' feeds (US) in the 1950s (see Wikipedia)

Since then :

"“Supplementing animal feed with antimicrobial agents to enhance growth has been common practice for more…

The Antimatter Problemplugin-autotooltip__plain plugin-autotooltip_bigThe Antimatter Problem

According to Big Bang Theory, matter and anti-matter should have been created in equal amounts. And, in experiments with high-energy particle accelerators, that is exactly what happens. Baryons (i.e. 'heavy' particles such as neutrons, protons, a…

Antimatter comets and meteorsplugin-autotooltip__plain plugin-autotooltip_bigAntimatter comets and meteors

Since the 1940's antimatter comets and meteors have been suggested as one possible explanation for various observed natural phenomena - e.g. 'explosive' meteor strikes, gamma-ray bursts, ball lightning etc etc.

"If the solar system forme…

Anti-Neutrinosplugin-autotooltip__plain plugin-autotooltip_bigAnti-Neutrinos

"The electron neutrino has a corresponding antiparticle, the electron antineutrino (νe), which differs only in that some of its properties have equal magnitude but opposite sign. One open question of particle physics is whether or not neutrinos and anti…

'Anting' behaviour in bird speciesplugin-autotooltip__plain plugin-autotooltip_big'Anting' behaviour in bird species

"Anting behaviour may be defined as the stereotyped movements with which birds, in order to get formic acid (or other organic liquids) on to the feathers for some purpose as yet not fully understood, actively apply ants (or objects i…

Apollo Syndromeplugin-autotooltip__plain plugin-autotooltip_bigApollo Syndrome

A 2016 study into cardiovascular disease (CVD) amongst members of the NASA Apollo missions found that the CVD mortality rate in Apollo lunar astronauts was 4–5 times higher than in non-flight and Low Earth Orbit astronauts.

"“[

Appendicitis etiologyplugin-autotooltip__plain plugin-autotooltip_bigAppendicitis etiology

The incidence of appendicitis is highest among adolescents and young adults (13–40 years of age) (source World Journal of Surgery).

Because the appendix has no known function (it's considered an a vestigial organ) and since the disease has a fa…

Appetite Regulationplugin-autotooltip__plain plugin-autotooltip_bigAppetite Regulation

Very extensive research, over many decades, has identified a number of biochemical routes that can influence appetite in humans.

For an overview, see: Mechanisms of Appetite Regulation

In particular, the so called 'hunger hormones' leptin and ghre…

April fools' dayplugin-autotooltip__plain plugin-autotooltip_bigApril fools' day

The April Fools Day tradition is widely celebrated on April 1st. across much of Europe and the Americas.

The origins of the tradition appear to have have been lost.

Several conflicting theories have emerged - such as the idea that it's a continuation…

Archaeomeplugin-autotooltip__plain plugin-autotooltip_bigArchaeome

The human Microbiome (a.k.a. Microbiota) has been the focus of intense research for many decades. We are hosts to a vast array of microorganisms, including bacteria, eukaryotes, archaea, fungi and viruses - many of which are now known to be beneficial to hum…

Arm swinging (in human walking)plugin-autotooltip__plain plugin-autotooltip_bigArm swinging (in human walking)

In general, humans tend to swing their arms in sync (but out-of-phase) with their walking strides. Although the muscle-driven arm swinging must incur at least some energy costs, three recent experimental studies have shown that

Arterial sclerosis (a.k.a Atherosclerosis)plugin-autotooltip__plain plugin-autotooltip_bigArterial sclerosis (a.k.a Atherosclerosis)

Arterial sclerosis (a.k.a. atherosclerosis) is an extremely common condition which can cause coronary thrombosis, myocardial infarction and other serious conditions. However:

"“The atherosclerotic process is not fully unders…

Artesunateplugin-autotooltip__plain plugin-autotooltip_bigArtesunate

Artesunate is a widely prescribed drug used to treat severe malaria infections. It was developed in the mid 1970s, and is now on the World Health Organization's List of Essential Medicines.

It was originally derived from Artemisinin , a compound extracted f…

Artificial sweetenersplugin-autotooltip__plain plugin-autotooltip_bigArtificial sweeteners

"“Artificial sweetener consumption is widely believed to be an effective method to limit caloric intake and maintain glycemic control. However, there is no evidence from long-term prospective analyses that the consumption of artificial sweeteners…

Asparagus odour in urineplugin-autotooltip__plain plugin-autotooltip_bigAsparagus odour in urine

There are two as yet unexplained enigmas regarding the unusual odour of the urine of those who have recently eaten asparagus.

1) The odour-causing molecules have not been unequivocally identified.

2) Some individuals cannot smell the odour at…

Asthmaplugin-autotooltip__plain plugin-autotooltip_bigAsthma

Asthma is a common, (and currently incurable) long term inflammatory disease of the airways of the lungs, characterized by variable and recurring symptoms such as reversible airflow obstruction, and bronchospasm. Episodes of asthma frequently feature wheezing, c…

Autismplugin-autotooltip__plain plugin-autotooltip_bigAutism

Autism is a developmental disorder characterized by difficulties with social interaction and communication, and by restricted and repetitive behaviour. The causes of autism are unknown, though it's likely that there is a strong genetic component. Current theory …

Autoantibodiesplugin-autotooltip__plain plugin-autotooltip_bigAutoantibodies

An autoantibody is an antibody (a type of protein) produced by the immune system that acts against one or more of the individual's own proteins.

"The causes of autoantibody production are varied and not well understood. It is thought that some autoanti…

Automerizationplugin-autotooltip__plain plugin-autotooltip_bigAutomerization

Automerization is the name given to a process where carbon-ring chemicals tend to spontaneously transform into closely-related chemicals when heated.

The first example found was the transformation of azulene to naphthalene.

The 'reactions' involve a re…

Avian clutch sizes and latitudeplugin-autotooltip__plain plugin-autotooltip_bigAvian clutch sizes and latitude

Avian clutch size - the average number of eggs found in a particular (or comparable) bird species nest - often correlates with latitude.

The effect was discovered in the 1940s, and has been extensively researched since then. In general…

Avian flight evolutionplugin-autotooltip__plain plugin-autotooltip_bigAvian flight evolution

It's now widely agreed that modern-day birds evolved, during the Mesozoic Era, from dinosaur species which survived the Cretaceous / Tertiary extinction event. (See: Avian K-T survival )

But the question of how and why birds acquired the ability…

Avian K-T survivalplugin-autotooltip__plain plugin-autotooltip_bigAvian K-T survival

It's now widely accepted that the Cretaceous–Tertiary (K–T) extinction event (also known as the The Cretaceous–Paleogene (K–Pg) extinction event) played a large part in the extinction of the non-avian dinosaurs. (see : Dinosaur extinction )

The bra…

Avian vocal mimicryplugin-autotooltip__plain plugin-autotooltip_bigAvian vocal mimicry

Many species of birds are extremely adept at mimicking both the calls of other birds, and other animal and non-animal sounds. Notably parrots and Minah birds - but also documented in blackbirds, bower birds, sparrows, lyrebirds, robins, owls etc etc…

Bacterial swarming motilityplugin-autotooltip__plain plugin-autotooltip_bigBacterial swarming motility

"Swarming motility is a rapid (2–10 μm/s) and coordinated translocation of a bacterial population across solid or semi-solid surfaces, and is an example of bacterial multicellularity and swarm behaviour. Swarming motility was first reported…

Ball Lightningplugin-autotooltip__plain plugin-autotooltip_bigBall Lightning

Ball Lightning refers to luminous, usually spherical, atmospheric objects which vary from a few centimetres to several metres in diameter. They are usually associated with thunderstorms. Anecdotal reports suggest that they can 'pass through' solid object…

Beal's conjectureplugin-autotooltip__plain plugin-autotooltip_bigBeal's conjecture

"If Ax + By = Cz, where A, B, C, x, y and z are positive integers and x, y and z are all greater than 2, then A, B and C must have a common prime factor."

Source : bealconjecture.com

The conjecture was proposed in 1993 by self-taught mathematician

Bee Colony Collapse Disorder [ CCD ]plugin-autotooltip__plain plugin-autotooltip_bigBee Colony Collapse Disorder [ CCD ]

"“Colony collapse disorder (CCD) is the phenomenon that occurs when the majority of worker bees in a colony disappear and leave behind a queen, plenty of food and a few nurse bees to care for the remaining immature bees and the que…

The Beeswax wreckplugin-autotooltip__plain plugin-autotooltip_bigThe Beeswax wreck

The beeswax wreck is an as-yet-undiscovered shipwreck which is believed to be located somewhere off the coast of the U.S. state of Oregon, near the mouth of the Nehalem River in Tillamook County. The ship, thought to be a Spanish Manila galleon that w…

Behçet's diseaseplugin-autotooltip__plain plugin-autotooltip_bigBehçet's disease

"Behçet’s Syndrome (also known as Behçet’s Disease or, simply, Behçet’s) is a chronic condition resulting from disturbances in the body’s immune system. This system, which normally protects the body against infections by producing controlled inflammat…

Bellman's 'Lost in a forest' problemplugin-autotooltip__plain plugin-autotooltip_bigBellman's 'Lost in a forest' problem

- can (colloquially) be stated like this :

"“A hiker is lost in a forest whose shape and dimensions are precisely known to him. What is the best path for him to follow to escape from the forest?” It is usually assumed that the hik…

Bell's palsyplugin-autotooltip__plain plugin-autotooltip_bigBell's palsy

Bell's palsy is a temporary facial paralysis (typically lasting 6 weeks to 6 months) that results from damage to the nerves which control facial muscles. It's usually one-sided, and has been estimated to affect around 1.5% of the global population at some…

Benzene structureplugin-autotooltip__plain plugin-autotooltip_bigBenzene structure

The benzene molecule is composed of 6 carbon atoms joined in a ring with 1 hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.

Although the compound has been very extensively studi…

Benign fasciculation syndrome (BFS)plugin-autotooltip__plain plugin-autotooltip_bigBenign fasciculation syndrome (BFS)

Benign fasciculation syndrome (BFS) is a neurological disorder characterized by fasciculation (twitching) of various voluntary muscles in the body. The twitching can occur in any voluntary muscle group but is most common in the eyeli…

Bicycle designplugin-autotooltip__plain plugin-autotooltip_bigBicycle design

The earliest bicycles had no integrated means of propulsion - being essentially unpowered seated 'scooters'. The invention of the 'crank' - in other words the attachment of powering pedals to the wheel - appears to be a lost historical event :

Bicycle dynamicsplugin-autotooltip__plain plugin-autotooltip_bigBicycle dynamics

Riderless bicycles (hand launched) tend to self-stabilise whilst in forward motion.

The phenomenon has been extensively studied at the Delft University of Technology (NL) in collaboration with Cornell University (US) (videos here)

The physics behind …

Big Bang theoryplugin-autotooltip__plain plugin-autotooltip_bigBig Bang theory

There is now a large body of evidence to support the Big Bang Theory for the origin of the universe, but the problem remains as to the origin of the material or energy which initialised it. As the UK’s Astronomer Royal Martin Rees has put it :

"“We d…

Bilobalideplugin-autotooltip__plain plugin-autotooltip_bigBilobalide

Bilobalide is a main constituent of organic chemicals called terpenoids which are found in the leaves of Ginkgo biloba, a tree which has leaves that are used in herbal medicine. Its exact synthesis pathway from farnesyl pyrophosphate is still unknown. Source…

Bird flockingplugin-autotooltip__plain plugin-autotooltip_bigBird flocking

Many theories have been put forward to explain large-scale flocking and roosting behaviour in birds. But from an evolutionary point of view, all the theories have clear drawbacks.

Ideas include:

• Heat conservation - but in many roosts the birds maintai…

Bird Migrationplugin-autotooltip__plain plugin-autotooltip_bigBird Migration

Around 50% of birds migrate (i.e. undertake large-scale routine long distance travel for breeding / feeding).

The distances covered can be huge - e.g. Manx Shearwaters migrate 14,000 km (8,700 mi) each year. The time-triggers, and the methods of route n…

Bird Unipedalismplugin-autotooltip__plain plugin-autotooltip_bigBird Unipedalism

At least 56 species of birds habitually stand on one leg for long periods. The reasons are disputed :

"“Flamingos are thought to stand on one leg to reduce muscle fatigue or heat loss. The muscle fatigue hypothesis assumes that standing for long peri…

Human birth defectsplugin-autotooltip__plain plugin-autotooltip_bigHuman birth defects

Birth defects - sometimes severe - occur at a rate of roughly 1 per 33 births worldwide. Which currently equates to nearly 8 million per year.

Of these, approximately 20% can be accounted for (genetic defects, smoking, viruses and bacteria, obesity…

'Bloke' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Bloke' etymology

"Bloke (n.) “fellow,” 1851, also bloak, London slang, of unknown origin, perhaps from Celtic ploc “large, stubborn person;” another suggestion is Romany (Gypsy) and Hindi loke “a man.” Source: Etymology online"

Note: The Online Etymology Dictionary …

Blushingplugin-autotooltip__plain plugin-autotooltip_bigBlushing

"“... the most peculiar and most human of all expressions.” - according to Charles Darwin."

Blushing is the temporary reddening of a person's face due to (apparently specialised) blood vessel dilation mechanisms. It is normally involuntary and triggered by e…

Body Temperature Declineplugin-autotooltip__plain plugin-autotooltip_bigBody Temperature Decline

A 2020 study from Stanford University has found that human body temperature - previously standardised at 37°C - has been steadily declining over the last 200 years or so.

Using historical records, the research team found that the current avera…

Chemical bondingplugin-autotooltip__plain plugin-autotooltip_bigChemical bonding

Chemistry textbooks describe three types of chemical bonds - the strong attraction between atoms, ions or molecules that enables the formation of all chemical compounds.

* The Ionic bond * The Covalent bond * The Metallic bond

'Boost' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Boost' etymology

"Boost (v.) “to lift or raise by pushing from behind,” 1815, literal and figurative, American English, of unknown origin. Related: Boosted; boosting. As a noun, “a lift, a shove up, an upward push,” by 1825. Source: Etymology Online "

Note:

'Borg' DNAplugin-autotooltip__plain plugin-autotooltip_big'Borg' DNA

'Borgs' are newly discovered (2021) extra-chromosomal elements - in the form of large functional DNA sequences - that are found in the cell nucleus, but outside the chromosomes.

They have been discovered, in abundance, in some species of the micro-organisms

Bose Novaeplugin-autotooltip__plain plugin-autotooltip_bigBose Novae

Under certain conditions, atoms in Bose-Einstein Condensates (BEC) - ultra-low temperature 'gasses' of expanded, superimposed atoms - can sometimes become unstable in intense magnetic fields.

Bowman's layerplugin-autotooltip__plain plugin-autotooltip_bigBowman's layer

"The Bowman's membrane (Bowman's layer, anterior limiting lamina, anterior elastic lamina) is a smooth, acellular, nonregenerating layer, located between the superficial epithelium and the stroma in the cornea of the eye. Source : Wikipedia"

'Boy' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Boy' etymology

"“Boy (n.) Mid-13c., boie “servant, commoner, knave, boy,” of unknown origin. Possibly from Old French embuie “one fettered,” from Vulgar Latin *imboiare, from Latin boia “leg iron, yoke, leather collar,” from Greek boeiai dorai

Human brain-size reductionplugin-autotooltip__plain plugin-autotooltip_bigHuman brain-size reduction

Fossil records from across the world show that average human brain-sizes have been decreasing for approx. 30,000 years - and especially over the last 10,000. There are various theories regarding the trend (including 'domestication' and inheri…

The 'Brain in a vat' problemplugin-autotooltip__plain plugin-autotooltip_bigThe 'Brain in a vat' problem

Philosophers have been puzzling over the 'Brain in a Vat' problem for several decades. The 'problem' comes down to arguments over whether it's possible (or not) to philosophically 'prove' that one (i.e. the observer) is not simply an isolat…

Brainstem gliomasplugin-autotooltip__plain plugin-autotooltip_bigBrainstem gliomas

"Brain stem gliomas are primary tumors occurring in the brain stem, the deep central/posterior part of the brain that connects the rest of the brain to the top of the spinal cord. The brain stem consists of the medulla, pons, and midbrain. This criti…

Brodmann area 10plugin-autotooltip__plain plugin-autotooltip_bigBrodmann area 10

Brodmann area 10 (a.k.a. BA10, frontopolar prefrontal cortex, rostrolateral prefrontal cortex, or anterior prefrontal cortex) is a frontal lobe area in the human brain which has been found to be generally associated with working memory and multiple-tas…

Bruxismplugin-autotooltip__plain plugin-autotooltip_bigBruxism

Bruxism is excessive teeth grinding or jaw clenching that is unrelated to normal functions such as eating or talking.

Estimates vary as to its prevalence - between 8% and 31% of the total population.

It's classified into two different types, 'awake' bruxism …

'Bunting' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Bunting' etymology

"Bunting (n.1) “light woolen stuff loosely woven, flag-material,” 1742, of uncertain origin; perhaps from a dialectal survival of Middle English bonting “sifting,” verbal noun from bonten “to sift,” because cloth was used for sifting grain. The Mid…

Byblos scriptplugin-autotooltip__plain plugin-autotooltip_bigByblos script

The Byblos script, also known as the Byblos syllabary, is an undeciphered writing system originally found on bronze tablets from Byblos, Lebanon. Since then, other examples have been found in Egypt, Italy and Israel.

The number of signs or glyphs is arou…

Cable Bacteriaplugin-autotooltip__plain plugin-autotooltip_bigCable Bacteria

Cable bacteria are filamentous bacteria, found in aqueous sediments, which form chains that conduct electricity. They transfer electrons across distances over 1cm (possibly more) in sediment and groundwater aquifers. They enable the reduction of oxygen a…

Caloric restrictionplugin-autotooltip__plain plugin-autotooltip_bigCaloric restriction

"“Calorie restriction, or caloric restriction, or energy restriction, is a dietary regimen that reduces calorie intake without incurring malnutrition or a reduction in essential nutrients. 'Low' can be defined relative to the subject's previous int…

Calpainopathyplugin-autotooltip__plain plugin-autotooltip_bigCalpainopathy

Calpainopathy (a.k.a. LGMDR1) is the most common type of autosomal recessive limb-girdle muscular dystrophy (LGMD) It affects the muscles of the hip girdle and shoulder girdle.

Symptoms usually appear between the ages of 8 and 15. In severe cases, pati…

Carbocatalysisplugin-autotooltip__plain plugin-autotooltip_bigCarbocatalysis

"“Carbocatalysis is a form of catalysis that uses heterogeneous carbon materials for the transformation or synthesis of organic or inorganic substrates. The catalysts are characterized by their high surface areas, surface functionality, and large, aroma…

Carbonados are an amorphous form of crystallised diamond carbon. Generally found as pea sized (or larger) pebbles, to date they have only been found in the Central African Republic and Brazil, usually embedded in sedimentary rocks.

Their origin is as yet une…

Carboniferous gigantismplugin-autotooltip__plain plugin-autotooltip_bigCarboniferous gigantism

Fossils show that during the Earth's Late Carboniferous period (around 300 million years ago) there were several species of insects - e.g. Meganeura (giant dragonflies) and Arthropleura (giant millipedes) - which reached sizes far larger than k…

Carbyneplugin-autotooltip__plain plugin-autotooltip_bigCarbyne

Carbyne ( a.k.a. Linear Acetylenic Carbon - LAC) is a monovalent allotrope of carbon with three non-bonded electrons having the chemical structure (−C≡C−)n in a (long) repeating chain, with alternating single and triple bonds.

In the same way that graphene is …

Carotid Body Mechanismplugin-autotooltip__plain plugin-autotooltip_bigCarotid Body Mechanism

The level of oxygen present in mammalian blood - critical for survival - is controlled by a complex feedback system triggering more or less breathing, alterations in blood pressure etc.. It's dependent on 'sensors', one primary sensor is called t…

Carpal Tunnel Syndromeplugin-autotooltip__plain plugin-autotooltip_bigCarpal Tunnel Syndrome

"Carpal tunnel syndrome (CTS) occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist. The carpal tunnel—a narrow, rigid passageway of ligament and bones at the base of the ha…

Castleman diseaseplugin-autotooltip__plain plugin-autotooltip_bigCastleman disease

Casleman Disease is a condition which leads to lymph node enlargements and dysfunction. It was first described in 1956, and since then three types have been identified :

• Unicentric Castleman disease (UCD) • Idiopathic multicentric Castleman diseas…

Catatoniaplugin-autotooltip__plain plugin-autotooltip_bigCatatonia

"Catatonic disorders are a group of symptoms characterized by disturbances in motor (muscular movement) behavior that may have either a psychological or a physiological basis. The best-known of these symptoms is immobility, which is a rigid positioning of th…

Catnipplugin-autotooltip__plain plugin-autotooltip_bigCatnip

The herbaceous plant Catnip (Nepeta cataria) dramatically affects several members of the cat family (Felidae) causing them to sniff, roll over, and undulate the skin on their back (amongst other things).

Although it generally only affects about 50% of cats, the…

Cell Differentiationplugin-autotooltip__plain plugin-autotooltip_bigCell Differentiation

"“The mechanisms that link cellular differentiation programs and dynamic gene regulation in complex eukaryotic systems remain mysterious. Such programs drive diverse and central biological processes including organismal development, immune functio…

Cellular organellesplugin-autotooltip__plain plugin-autotooltip_bigCellular organelles

Eukaryotic cells are cells which have a nucleus. Within that nucleus are various discrete structures with very specific functions that are, as a group, called 'organelles'.

In the 1970s a book by professor Lynn Margulis (titled Origin of Eukaryotic…

Cell proliferationplugin-autotooltip__plain plugin-autotooltip_bigCell proliferation

When organic 'tissue' grows (either during embryonic development, post-natal growth, or tissue regeneration) there are two processes in operation which determine the final size of the tissue or organ. The first is the size of the cells themselves - w…

Cell sizeplugin-autotooltip__plain plugin-autotooltip_bigCell size

A detailed explanation of the factors which regulate cell size (i.e. the size to which cells grow) has not yet been found. Since (most) cells stop growing when they reach a specific size, it's suggested that there must be some feedback mechanism to restrict g…

Cementplugin-autotooltip__plain plugin-autotooltip_bigCement

Cements of various types have been in more or less constant use since at least Roman times. However, the ways in which cements set (via a complex series of chemical hydration reactions) are still not fully described.

"“The hydration of cement is an extremely …

Cranial Electrotherapy Stimulationplugin-autotooltip__plain plugin-autotooltip_bigCranial Electrotherapy Stimulation

Cranial Electrotherapy Stimulation (a.k.a. cranial-electro stimulation and transcranial electrotherapy) is the application of small electrical currents (e.g.1mA) to the brain externally via electrodes on the scalp. It has been in use…

Cetacean strandingsplugin-autotooltip__plain plugin-autotooltip_bigCetacean strandings

It's currently estimated that around 2,000 whales and dolphins are 'stranded' (i.e. run aground) each year. The majority of strandings result in death. Only about 10 cetacean species frequently display mass beachings, and another 10 do so occasiona…

CO2 fertilization effect ( CFE )plugin-autotooltip__plain plugin-autotooltip_bigCO2 fertilization effect ( CFE )

The CO2 Fertilization Effect refers to the fact that increased atmospheric CO2 levels can encourage plant growth. This is a well known effect, and is exploited in farms which grow crops in greenhouses with artificially elevated CO

Chandler Wobbleplugin-autotooltip__plain plugin-autotooltip_bigChandler Wobble

"“The Chandler wobble is an excited resonance of the Earth's rotation having a period of about 14 months. Although it has been under investigation for more than a century, its excitation mechanism ha…

Chaos Theoryplugin-autotooltip__plain plugin-autotooltip_bigChaos Theory

Chaos theory is the concept that the behaviour of some complex dynamical systems (e.g. global weather patterns) can be extremely sensitive to tiny changes in initial conditions — thus making accurate and specific long-term predictions about the system unre…

Charniaplugin-autotooltip__plain plugin-autotooltip_bigCharnia

"Charnia is a highly significant fossil because it is the first fossil which was ever described to have come from undoubted Precambrian rocks. Prior to 1958, the Precambrian was thought to be completely devoid of fossils and consequently possibly devoid of mac…

Cherry angiomaplugin-autotooltip__plain plugin-autotooltip_bigCherry angioma

Cherry angioma (a.k.a. Campbell de Morgan spots, Strawberry Naevi and Red Moles) are small, harmless (non cancerous) skin tumours which have an abnormally high number of surface blood capillaries - hence their red colouration and name.

Chillsplugin-autotooltip__plain plugin-autotooltip_bigChills

Note: This item refers to the emotionally or imaginatively triggered sensation of 'Frisson' rather than shiver reactions caused by cold or fever etc.

Chills, 'goosebumps' etc can be induced in a number of ways: musical, scenic, tactile, and even taste sensation…

Chitinozoaplugin-autotooltip__plain plugin-autotooltip_bigChitinozoa

Chitinozoans are bottle-shaped marine microfossils which thrived during the Ordovician, Silurian, and Devonian periods. They often have root-like structures at the base of the 'flask'. They were first described in 1931 by the German micropaleontologist Alfre…

Chondrulesplugin-autotooltip__plain plugin-autotooltip_bigChondrules

Chondrules are the oldest objects in the Solar System. They are small, generally are 0.1 to 1 mm in diameter. (Chondrules outside of this range have been observed, but are rare.) They are spherical rock-based granules that make up around 60-80% of a typical…

Chromium as a micronutrientplugin-autotooltip__plain plugin-autotooltip_bigChromium as a micronutrient

The metal Chromium - specifically Chromium(III), the trivalent ion - has been suggested by some researchers as an essential micronutrient. Other groups claim that it isn't essential, but that its presence can be of benefit. It's commonly fo…

Chronic fatigue syndromeplugin-autotooltip__plain plugin-autotooltip_bigChronic fatigue syndrome

Symptoms : mental and physical exhaustion, muscle pain and overwhelming tiredness.

"“The cause of CFS is unknown, and multiple psychological and physiological factors may contribute to the development and maintenance of symptoms. There is no …

In North America, Cicadas spend most of the lifespan as underground larvae known as nymphs. Depending on the species, they emerge en-masse as winged adults after either 13 years or 17 years. When this behaviour was originally discovered, it was noted t…

Compact Intracloud Discharges (CIDs)plugin-autotooltip__plain plugin-autotooltip_bigCompact Intracloud Discharges (CIDs)

"“A compact intracloud discharge (CID), also known as a narrow bipolar event (NBE) or narrow bipolar pulse (NBP) is an intensive form of lightning that produces radio waves and scarce visible light. Lasting only a few millionths of…

Cieplak effectplugin-autotooltip__plain plugin-autotooltip_bigCieplak effect

In organic chemistry, the Cieplak effect refers to a proposal (from Andrzej Stanislaw Cieplak in 1980) to try to explain why nucleophiles (organic chemicals that, in reactions, donate an electron pair to form a chemical bond) preferentially add to one fa…

Circular RNAplugin-autotooltip__plain plugin-autotooltip_bigCircular RNA

“Thought to result from splicing errors, circular RNA species possess no known function.” Source RNA Journal 2013.

RNA usually occurs in strands, but can also form circular loops. It's predominantly found in the cell's cytoplasm - i.e. outside the cell nu…

Clemmensen reductionplugin-autotooltip__plain plugin-autotooltip_bigClemmensen reduction

"[The] Clemmensen reduction is a chemical reaction described as a reduction of ketones (or aldehydes) to alkanes using zinc amalgam and concentrated hydrochloric acid . Source: Wikipedia"

The reaction, which is used for converting a carbonyl gro…

Cloud forcingplugin-autotooltip__plain plugin-autotooltip_bigCloud forcing

Cloud Forcing (a.k.a. Cloud Radiative Forcing (CRF) or Cloud Radiative Effect (CRE)) refers to the complex effects which cloud cover has on the Earth's 'radiation budget' - in other words how much they affect warming by the Sun.

Clouds can reflect (heat…

Cloud ice formationplugin-autotooltip__plain plugin-autotooltip_bigCloud ice formation

The formation of ice crystals have important implications for stratospheric ozone chemistry, cloud dynamics, rock weathering, and hydrate formation etc., however the exact mechanisms by which microscopic particulate matter 'seeds' ice-crystals are u…

"“Cluster headache (CH) always involves pain that is one sided (although it can switch sides) and the main defining feature is the association with one or more of the 'cranial autonomic' features normally described as follows: • Reddening and tearing …

Cosmic Microwave Background excessplugin-autotooltip__plain plugin-autotooltip_bigCosmic Microwave Background excess

"The cosmic microwave background (CMB) is currently our most precise window on the physics of the early universe. Measurements of the frequency spectrum of the CMB can rule out alternative cosmologies and place limits on physical pro…

Colchicineplugin-autotooltip__plain plugin-autotooltip_bigColchicine

Colchicine is an anti-inflammatory medication used to treat Gout and Behçet's disease. Sold under the brand names Colcrys, Mitigare, Gloperba and many others.

It was originally isolated from a herbal remedy - the Autumn Crocus plant - in use for at least 3,…

Cold fusionplugin-autotooltip__plain plugin-autotooltip_bigCold fusion

Cold fusion is a disputed physical effect that was first reported in 1989. It suggests that it may be possible to achieve room-temperature 'fusion' whereby energy is produced due to the fusion of atomic nuclei.

(It's called 'cold' because the alternative n…

Collatz conjectureplugin-autotooltip__plain plugin-autotooltip_bigCollatz conjecture

Using the formula :

$${\displaystyle f(n)={\begin{cases}{\frac {n}{2}}\quad\quad\quad{\text{if }}n\equiv 0{\pmod {2}}\\[4px]3n+1\quad{\text{if }}n\equiv 1{\pmod {2}}.\end{cases}}}$$

The Collatz conjecture states that this process will eventually …

Colour perceptionplugin-autotooltip__plain plugin-autotooltip_bigColour perception

Although it has been very well established that human eyes have three* [see note below] different types of retinal cells (cone cells) which respond differently to coloured light (i.e. different wavelengths) - it's also known that colour vision is

Consciousnessplugin-autotooltip__plain plugin-autotooltip_bigConsciousness

Does an ant carrying a piece of leaf across the forest floor ‘know’ it’s doing so? Is it conscious? If science could construct a machine as complex as the human brain, would it ‘know’ it existed? Will it oneday be possible to explain consciousness via the…

Conformal cyclic cosmologyplugin-autotooltip__plain plugin-autotooltip_bigConformal cyclic cosmology

Conformal Cyclic Cosmology (CCC) is a concept proposed in 2006 by the Nobel Prize winning cosmologist Professor Roger Penrose. It attempts to resolve a paradox associated with (standard) Big Bang theory.

"“The issue arises from one of the m…

Connectome formationplugin-autotooltip__plain plugin-autotooltip_bigConnectome formation

The Connectome is the name given to the map of neural connections within an organism's nervous system. Analogous to the 'wiring diagram' of a machine. See: Wikipedia

When organisms are growing - in the sense of 'wiring up' their nervous system, th…

Physical constantsplugin-autotooltip__plain plugin-autotooltip_bigPhysical constants

Constants variability :

Many physics calculations rely on the assumption that the ‘physical constants’ e.g. light speed, gravity, etc etc are, in fact, constant. Extremely accurate experimental procedures strongly suggest that they (mostly) are. But…

Contagious Yawningplugin-autotooltip__plain plugin-autotooltip_bigContagious Yawning

Most people have seen examples of Contagious Yawning in humans. If one person in a group yawns (or convincingly feigns a yawn) it's often quite hard for others to resist. Current estimates are that 40-60% of human yawns are 'contagious'.

Coral spawningplugin-autotooltip__plain plugin-autotooltip_bigCoral spawning

"“Broadcast spawning by corals is an amazingly precise temporal process. Every year, on just one or two evenings, many of the individuals of each broadcast spawning species release their gametes in a time window that is usually approximat…

Core Clockplugin-autotooltip__plain plugin-autotooltip_bigCore Clock

In humans, and most [all?] other mammals, the 'Core Clock' which regulates variations in body functions is set to (approximately) 24 hours. This is the so-called Circadian Rhythm. - which in many organisms, is synchronised via daylight.

The clock is regul…

Coronal heating problemplugin-autotooltip__plain plugin-autotooltip_bigCoronal heating problem

The Sun's outer corona - stretching millions of kilometers out into space from the surface - reaches temperatures of up to 4 million degrees C.. This contrasts sharply with the surface of the sun which is measured as around 6 thousand degrees C…

Coronary vasospasmplugin-autotooltip__plain plugin-autotooltip_bigCoronary vasospasm

Coronary vasospasm or Coronary Artery Spasm is a condition in which the arteries which supply the heart spontaneously constrict - leading to a lack of oxygen and a type of angina (chest pain) called Vasospastic angina or Prinzmetal angina

Corpus callosumplugin-autotooltip__plain plugin-autotooltip_bigCorpus callosum

The Corpus Callosum (Latin for 'tough body') is a large bundle of nerve fibres which serves to 'connect' the right and left hemispheres of the mammalian brain - except in marsupials (e.g. Kangarooo) and monotremes (e.g. Platypus).

Put another way, it's…

Cosmic raysplugin-autotooltip__plain plugin-autotooltip_bigCosmic rays

"“Cosmic rays are typically protons or atomic nuclei of elements such as helium, carbon, or iron. The most energetic have energies more than 10 million times greater than those in the world’s most powerful atom smasher, the Large Hadron Collider.

Cosmological Constant Problemplugin-autotooltip__plain plugin-autotooltip_bigCosmological Constant Problem

The cosmological constant problem is the disagreement in 'measured' values of the cosmological constant and theoretical calculations of its value.

The cosmological constant was first proposed by Einstein as a mathematical necessity to rat…

Cosmological Magnetic Fieldsplugin-autotooltip__plain plugin-autotooltip_bigCosmological Magnetic Fields

"“Magnetic fields are observed on nearly all scales in the universe, from stars and galaxies upto galaxy clusters and even beyond. The origin of cosmic magnetic fields is still an open question, however a large class of models puts its ori…

Covid-19plugin-autotooltip__plain plugin-autotooltip_bigCovid-19

Editor's note : Because of the intense, ongoing, global research efforts related to Covid-19, it's difficult to get an accurate picture of the unknown factors. Here are some of the many as-yet-unanswered questions Why does the virus have much more serious eff…

Crampplugin-autotooltip__plain plugin-autotooltip_bigCramp

Cramps (severe involuntary muscle contractions) are divided into two types - those that are triggered by strenuous exercise (exercise-associated muscle cramps) and those that occur without any easily identified cause - especially at night.

There are competing th…

Crohn's diseaseplugin-autotooltip__plain plugin-autotooltip_bigCrohn's disease

Crohn's disease is a type of inflammatory bowel disease (IBD) that can affect any part of the entire digestive tract. It causes inflammation and in severe cases, ulcers can form. Symptoms often include abdominal pain, diarrhea, fever, abdominal distensi…

Cromoglicic acidplugin-autotooltip__plain plugin-autotooltip_bigCromoglicic acid

"Cromoglicic acid (INN) — also referred to as cromolyn (USAN), cromoglycate (former BAN), or cromoglicate — is traditionally described as a mast cell stabilizer, and is commonly marketed as the sodium salt sodium cromoglicate or cromolyn sodium. This …

Cryingplugin-autotooltip__plain plugin-autotooltip_bigCrying

Crying is the shedding of tears (or welling of tears in the eyes) in response to an emotional state - as distinct from non-emotional 'lacrimation' which is the medical term for non-emotional shedding of tears (e.g. in response to peeling onions).

Cryopreservationplugin-autotooltip__plain plugin-autotooltip_bigCryopreservation

In 2018 it was announced that a multicellular organism - a species of nematode worm - had been successfully revived after having been frozen in the Arctic permafrost for around 30,000 years.

See: Viable Nematodes from Late Pleistocene Permafrost of th…

Low frequency e/m growth stimulationplugin-autotooltip__plain plugin-autotooltip_bigLow frequency e/m growth stimulation

All plants with chlorophyll utilise high frequency electromagnetic (e/m) radiation, in the form of light, as an essential part of their metabolism. (see Photosynthesis ).

Recent (2020) experiments with Arabidopsis thaliana - a comm…

Crystallizationplugin-autotooltip__plain plugin-autotooltip_bigCrystallization

Crystallization is the (natural or artificial) process by which a solid forms from solution, where the atoms or molecules are highly organized into a structure. Some aspects of the process, particularly nucleation have still not been completely describe…

Cuckoo declineplugin-autotooltip__plain plugin-autotooltip_bigCuckoo decline

"Since the early 1980s Cuckoo numbers [in the UK] have dropped by 65%. The reason for this decline is not known, but it has been suggested that declines in its hosts or climate-induced shifts in the timing of breeding of its hosts could have reduced the…

Cutaneous hornsplugin-autotooltip__plain plugin-autotooltip_bigCutaneous horns

Cutaneous horns, also known by the Latin name cornu cutaneum, are unusual skin tumours, formed from keratin, with the appearance of horns, or sometimes of wood or coral.

They are usually small and localized. Although often benign, they can also be mali…

Cutis Verticis Gyrata ( CVG )plugin-autotooltip__plain plugin-autotooltip_bigCutis Verticis Gyrata ( CVG )

"“Cutis verticis gyrata is a medical condition usually associated with thickening of the scalp. People show visible folds, ridges or creases on the surface of the top of the scalp. The number of folds can vary from two to roughly ten and …

Cell Wall Deficient Bacteria and Diseaseplugin-autotooltip__plain plugin-autotooltip_bigCell Wall Deficient Bacteria and Disease

As the name suggests, Cell Wall Deficient Bacteria (CWDB) are a group of bacteria - originally identified in 1935 - which lack a normal cell wall, e.g. Bacillus subtilis.

Some research groups have suggested that CWDB might caus…

Dark Energyplugin-autotooltip__plain plugin-autotooltip_bigDark Energy

"“The observational results of the latest 15 to 20 years have established a standard model for the cosmology which has some amazing consequences. A mysterious entity, the dark energy, has been confirmed as the dominant component of the Universe, and is als…

Dark Matterplugin-autotooltip__plain plugin-autotooltip_bigDark Matter

"“The nature of the dominant component of galaxies and clusters remains unknown.”

Source: Measuring the dark matter equation of state (Mon. Not. R. Astron. Soc. 415, L74–L77)"

In the 1930s, astronomical observations of galaxy rotations showed that the ou…

DCIS (ductal carcinoma in situ)plugin-autotooltip__plain plugin-autotooltip_bigDCIS (ductal carcinoma in situ)

DCIS (ductal carcinoma in situ) was first described in 1972, and is widely believed to be an indicator of the likelihood of developing invasive (i.e. metastasing) breast cancer.

Since the widespread introduction of x-ray based breast sc…

Deep Brain Stimulationplugin-autotooltip__plain plugin-autotooltip_bigDeep Brain Stimulation

Deep Brain Stimulation (DBS) is therapeutic neurosurgical procedure used in the treatment of Parkinson's disease and Tourette syndrome

See Wikipedia

It was introduced in 1997, and involves direct electrical stimulation (via implanted wires) of …

Deep Carbon life-formsplugin-autotooltip__plain plugin-autotooltip_bigDeep Carbon life-forms

Ongoing research into the prevalence of life-forms (predominantly bacteria and archaea) living deep in the Earth's crust is revealing them in previously unimagined quantities. Some estimate that the biological diversity of the life-forms exceeds …

Deep Diving Birdsplugin-autotooltip__plain plugin-autotooltip_bigDeep Diving Birds

Some birds - e.g. the Thick-billed_murre can dive as deep as 200m. On rapid resurfacing, they apparently suffer no ill effects - contrary to what would be expected due to the effects of Decompression_sickness

There is currently no explanation. A 1992…

Deepdiving animalsplugin-autotooltip__plain plugin-autotooltip_bigDeepdiving animals

Human divers need to resurface very slowly to avoid dangerous 'gas embolisms' which lead to decompression sickness (a.k.a. The Bends).

Deep-diving animals - e.g. whales, dolphins, turtles etc do not suffer the same problems (or very rarely do). The…

Defibrillationplugin-autotooltip__plain plugin-autotooltip_bigDefibrillation

Since the 1960s, electrical heart defibrillators have been routinely used as a treatment for life-threatening cardiac dysrhythmias, especially ventricular fibrillation. The exact mechanism of action is yet to be determined, but is presumably linked to la…

Dental Geminationplugin-autotooltip__plain plugin-autotooltip_bigDental Gemination

"Gemination can be described as teeth ‘twinning’. In dental context, gemination refers to a developmental irregularity in which a single tooth germ divides resulting in a bifid crown on a single root, that is, two teeth develop together from a single…

Dentin hypersensitivityplugin-autotooltip__plain plugin-autotooltip_bigDentin hypersensitivity

"Dentin hypersensitivity (DH, DHS) is dental pain which is sharp in character and of short duration, arising from exposed dentin surfaces in response to stimuli, typically thermal, evaporative, tactile, osmotic, chemical or electrical; and whic…

Dentigerous cystsplugin-autotooltip__plain plugin-autotooltip_bigDentigerous cysts

"A dentigerous cyst is an epithelial-lined cyst which involves the crown of an unerupted tooth in its cavity."

The cysts are the second most prevalent type of odontogenic cysts after radicular cysts. They are usually painless, and many patients (and…

Major Depressive Disorderplugin-autotooltip__plain plugin-autotooltip_bigMajor Depressive Disorder

Major depressive disorder (MDD), also known simply as depression, is a mental disorder characterized by at least two weeks of pervasive low mood.

Current estimates are that severe depression affects around 2% of the global population at any g…

Dermatomyositisplugin-autotooltip__plain plugin-autotooltip_bigDermatomyositis

"“Dermatomyositis is one of a group of muscle diseases known as the inflammatory myopathies, which are characterized by chronic muscle inflammation accompanied by muscle weakness. Dermatomyositis’ cardinal symptom is a skin rash that precedes, accompa…

Devonian extinction event(s)plugin-autotooltip__plain plugin-autotooltip_bigDevonian extinction event(s)

The Late Devonian extinction refers to an event, or series of events, in which more than 20% of all of Earth's marine life was eliminated.

Many entire biological 'families' of species permanently disappeared from the fossil records.

Diabetes (type 1)plugin-autotooltip__plain plugin-autotooltip_bigDiabetes (type 1)

Type 1 Diabetes is a chronic disease that occurs either when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin it produces. Insulin is a hormone required for the body to regulate and use blood sugar.

Diatom Structureplugin-autotooltip__plain plugin-autotooltip_bigDiatom Structure

"“The silicified cell walls of diatoms have inspired the interest of researchers for several centuries, and our understanding of their properties and formation has developed in synch with the development of observational and analytical techniques. Ove…

Dickinsoniaplugin-autotooltip__plain plugin-autotooltip_bigDickinsonia

Dickinsonia is the name given to range of extinct organisms which have left distinct fossil records. Since 1947, a total of nine species have been described. To date, the highly unusual nature of the organisms has left paleobiologists unable to properly cla…

Digit Ratioplugin-autotooltip__plain plugin-autotooltip_bigDigit Ratio

"“The digit ratio is the ratio of the lengths of different digits or fingers. The 2D:4D ratio is the most studied digit ratio and is calculated by dividing the length of the index finger of a given hand by the length of the ring finger of the same hand. A …

Dinosaur eggshell structureplugin-autotooltip__plain plugin-autotooltip_bigDinosaur eggshell structure

Many of the fossilised dinosaur eggs which have been found have significant surface detail - sometimes called 'decoration'.

The surface texture has been classified into six different types (see Wikipedia), which can in some cases be used t…

Dinosaur extinctionplugin-autotooltip__plain plugin-autotooltip_bigDinosaur extinction

"The question why non-avian dinosaurs went extinct 66 million years ago (Ma) remains unresolved because of the coarseness of the fossil record. A sudden extinction caused by an asteroid is the most accepted hypothesis but it is debated whether dino…

Dinosaur 'sails'plugin-autotooltip__plain plugin-autotooltip_bigDinosaur 'sails'

Several species of extinct dinosaurs independently evolved large, elaborate, sail-like structures on their backs. Examples include Edaphosaurus , Dimetrodon and Secodontosaurus

The function of the 'sails' has been investigated since the first days of …

Diquis spheresplugin-autotooltip__plain plugin-autotooltip_bigDiquis spheres

In the 1930's workers from the United Fruit Company, who were clearing land in the Diquís Valley Delta region of Costa Rica, began finding large numbers of almost perfectly round stone spheres.

The spheres, which range from a few kilograms up to around …

Disgustplugin-autotooltip__plain plugin-autotooltip_bigDisgust

Over the last 100 years or so, there has been a large volume of research into the human 'disgust' response.

See Wikipedia

Although there are (slight) cultural differences across the world, it's currently regarded as a truly 'innate' (rather than learned) emot…

Intrinsically disordered proteinsplugin-autotooltip__plain plugin-autotooltip_bigIntrinsically disordered proteins

Before year 2000, it was generally assumed that the way in which proteins 'folded' was the sole key to understanding their function in life-systems. (See :Protein structuring ). Since then, it has now been shown that many proteins do n…

Dispilio tabletplugin-autotooltip__plain plugin-autotooltip_bigDispilio tablet

"The Dispilio tablet is a wooden tablet bearing inscribed markings, unearthed during George Hourmouziadis's excavations of Dispilio in Greece, and carbon 14-dated to 5202 (± 123) BC. It was discovered in 1993 in a Neolithic lakeshore settlement that oc…

'Dixie' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Dixie' etymology

Dixie, also known as Dixieland, is a nickname for a region of the Southern United States. There is no official definition of the area of this region, but most include the states which belonged to the Confederate States of America (1860–65).

Dementia with Lewy Bodies (DLB)plugin-autotooltip__plain plugin-autotooltip_bigDementia with Lewy Bodies (DLB)

Dementia with Lewy Bodies (DLB) is characterized by the development of abnormal brain tissues known as Lewy bodies (and Lewy neurites) which are collections of alpha-synuclein protein within diseased brain neurons.

Like

DNA / RNAplugin-autotooltip__plain plugin-autotooltip_bigDNA / RNA

The vast majority of human DNA lies outside of the genes within the cells. Of this, recent work has discovered that 85% of these stretches of DNA appear to make RNA - which, for the most part, has yet-to-be-determined functions.

A study published in the onli…

'Dog' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Dog' etymology

"“Dog (n.) Old English docga, a late, rare word, used in at least one Middle English source in reference to a powerful breed of canine. The word forced out Old English hund (the general Germanic and Indo-European word; see canine) by 16c. and subsequen…

Delayed onset muscle sorenessplugin-autotooltip__plain plugin-autotooltip_bigDelayed onset muscle soreness

Delayed onset muscle soreness (DOMS) is the pain and stiffness felt in muscles some time after unaccustomed or strenuous exercise. The soreness usually increases in intensity in the first 24 hours after exercise, and peaks from 24 to 72 ho…

Donepezilplugin-autotooltip__plain plugin-autotooltip_bigDonepezil

Donepezil is a prescription-only drug used to alleviate some of the symptoms of Alzheimer's disease. There are currently around 5 million prescriptions per year in the US alone. It's sold under the brand names of Aricept, Namzaric and others.

The drug is a c…

Down syndromeplugin-autotooltip__plain plugin-autotooltip_bigDown syndrome

It has been known since 1959 that Down syndrome is a genetic condition caused by a random error in cell division that results in the presence of an extra copy (or part copy) of chromosome 21.

The parents of Down syndrome children are usually genetically …

Dreadlocks are are rope-like multiple strands of hair caused by locking or braiding hair. (see Wikipedia )

They way in which they form is unclear. They tend to be knotted throughout their length, from the scalp to the tip. If the knotting starts at…

Dreamingplugin-autotooltip__plain plugin-autotooltip_bigDreaming

"The content and purpose of dreams are not yet understood, though they have been a topic of speculation and interest throughout recorded history. Source : Wikipedia"

Not only is the function of dreaming unknown (if there is one), but there isn't as yet an ag…

Drumlinsplugin-autotooltip__plain plugin-autotooltip_bigDrumlins

"Drumlins are elongated hills of glacial deposits. They can be 1 km long and 500 m wide, often occurring in groups. A group of drumlins is called a drumlin swarm or a basket of eggs, eg Vale of Eden.[UK] Source : BBC Glacial Depostion"

They are formed from l…

Protein Domains of Unknown Functionplugin-autotooltip__plain plugin-autotooltip_bigProtein Domains of Unknown Function

A domain of unknown function (DUF) is a protein domain ( i.e. region of a protein's polypeptide chain that is self-stabilizing and folds independently from the rest.) that as yet has not had its function described.

Dupuytren's contractureplugin-autotooltip__plain plugin-autotooltip_bigDupuytren's contracture

"Dupuytren's contracture is a condition in which one or more fingers become permanently bent in a flexed position. It usually begins as small, hard nodules just under the skin of the palm, then worsens over time until the fingers can no longer …

Earthquake lightsplugin-autotooltip__plain plugin-autotooltip_bigEarthquake lights

'Earthquake Lights' [ EQL ] are airborne luminosities associated with seismic activity - reports of them go back more than 2000 years.

"“With the beginning of seismology as a science in the 19th century, many scholars devoted time to reporting lumin…

Earthquake predictionplugin-autotooltip__plain plugin-autotooltip_bigEarthquake prediction

"“In the 1970s, scientists were optimistic that a practical method for predicting earthquakes would soon be found, but by the 1990s continuing failure led many to question whether it was even possible. Demonstrably successful predictions of large…

Earwormsplugin-autotooltip__plain plugin-autotooltip_bigEarworms

Earworms are persistent (mostly unwanted) mental repetitions of musical phrases. It's also known as Stuck Song Syndrome and INvoluntary Musical Imagery (INMI). Surveys have shown the phenomenon to be very widespread - more than 90% of the general population h…

Echolocation (object recognition)plugin-autotooltip__plain plugin-autotooltip_bigEcholocation (object recognition)

Many animals (dolphins, bats, shrews, etc etc) can echolocate. That is, by emitting calls the environment and listening to the echoes of those calls that return from various objects near them. Some animals - for example dolphins - can…

Electroconvulsive therapy (ECT)plugin-autotooltip__plain plugin-autotooltip_bigElectroconvulsive therapy (ECT)

Electroconvulsive therapy (ECT), formerly known as electroshock therapy, is a psychiatric treatment in which seizures are electrically induced in patients, By an unknown mechanism, they provide relief from severe mental disorders - espec…

Eczemaplugin-autotooltip__plain plugin-autotooltip_bigEczema

The most common form (percentage needed) of Eczema is 'Atopic Eczema' - in this case 'atopic' meaning 'of unknown origin'.

It can occur anywhere on the body, but is common on the hands, elbows, knees, face and scalp.

A variety of factors, including environme…

EDP (skin abnormality)plugin-autotooltip__plain plugin-autotooltip_bigEDP (skin abnormality)

"Erythema dyschromicum perstans (EDP) is a form of acquired dermal macular hyperpigmentation characterised by well-circumscribed round to oval or irregular patches on the face, neck and trunk that are grey in colour. It is a form of acquired der…

Electroencephalographyplugin-autotooltip__plain plugin-autotooltip_bigElectroencephalography

Electroencephalography (EEG) is an electro-physiological non-invasive monitoring method to record electrical activity of the brain. Characteristic waveforms - e.g. the so-called Alpha-rhythm (sinusoidal-like waves with frequencies in 8–15 Hz rang…

Avian egg shapesplugin-autotooltip__plain plugin-autotooltip_bigAvian egg shapes

Many (but not all) bird eggs are non-spherical. There is currently disagreement as to how this happens.

"The shape of eggs varies considerably across bird species, ranging from near-spherical (such as those of the little bee-eater) to highly pyriform…

Egyptian Obelisk constructionplugin-autotooltip__plain plugin-autotooltip_bigEgyptian Obelisk construction

Ancient Egyptian obelisks are tapering stone pillars which have a square cross-section, and which are believed to have had religious, socio-political and ornamental functions. Some weigh more than 400 tons.They appear to have been 'carved…

Electric catfish immunityplugin-autotooltip__plain plugin-autotooltip_bigElectric catfish immunity

"For thousands of years, starting with detailed accounts from ancient Egypt, the African electric catfish (Malapteruridae) has been renowned for its ability to hunt and to defend itself with powerful electric shocks. Surprisingly, the degree …

Electromagnetic sensitivityplugin-autotooltip__plain plugin-autotooltip_bigElectromagnetic sensitivity

"People are immersed in electromagnetic fields from such sources as power lines, domestic appliances, mobile phones, and even electrical storms. All living beings sense electric fields, but the physical origins of the phenomenon are still u…

Electrostatic pollinationplugin-autotooltip__plain plugin-autotooltip_bigElectrostatic pollination

The idea that flying insects might be electrically charged during flight bystatic electricity was suggested almost 100 years ago. (Heuschmann, O. (1929). Über die elektrischen Eigenschaften der Insekten Haare, Journal of Comparative Physiology…

Elephant Floppy Trunk Syndromeplugin-autotooltip__plain plugin-autotooltip_bigElephant Floppy Trunk Syndrome

"“Floppy trunk syndrome (abbreviated FTS, also known as flaccid trunk paralysis) is a condition that causes trunk paralysis in African bush elephants. Initially observed in 1989, the syndrome primarily affected bull elephants in several …

EMDRplugin-autotooltip__plain plugin-autotooltip_bigEMDR

EMDR (Eye Movement Desensitization and Reprocessing) is a form of psychotherapy, which uses types of bilateral sensory input - typically side-to-side eye movements. It is designed to diminish negative feelings associated with memories of traumatic events, and is f…

Emotionsplugin-autotooltip__plain plugin-autotooltip_bigEmotions

Theories about emotions stretch back at least as far as the Stoics of ancient Greece – but to date, no definitive taxonomy of emotions exists. Though many have been proposed. And the biological necessity for some of the emotions (e.g. 'boredom' or 'shyness') r…

Enceladus is the sixth-largest moon of Saturn. about 500 km in diameter. It has been known since 2005 that it has higher surface temperatures than can currently be explained.

"Data from Cassini's composite infrared spectrometer of Enceladus' south p…

Encephalitis lethargicaplugin-autotooltip__plain plugin-autotooltip_bigEncephalitis lethargica

Encephalitis lethargica (also known as 'Sleepy Sickness') is a degenerative brain disease first described in 1917.

(NOTE: It should not be confused with 'Sleeping Sickness', which is caused by a parasite.)

The disease attacks the brain, leavin…

Endogenous Retrovirusesplugin-autotooltip__plain plugin-autotooltip_bigEndogenous Retroviruses

Endogenous retroviruses (ERVs) are viral elements found in the genome of vertebrates that closely resemble (and can be derived from) retroviruses. In humans, this 'rogue' DNA is believed to make up between 5 - 8% of the human genome.

Endometriosisplugin-autotooltip__plain plugin-autotooltip_bigEndometriosis

"Endometriosis is a condition in which cells similar to those in the endometrium, the layer of tissue that normally covers the inside of the uterus, grow outside the uterus. Most often this is on the ovaries, fallopian tubes, and tissue around the uterus…

Endophytesplugin-autotooltip__plain plugin-autotooltip_bigEndophytes

Endophytes (literally “inside plants”) were first found in 1809 by examining plant sections under the microscope. They are fungal, or bacterial, or viral inclusions in plant tissues – 'foreign' materials, found in very large numbers, that are permanent fixtu…

English shipwrecksplugin-autotooltip__plain plugin-autotooltip_bigEnglish shipwrecks

The UK's 'Historic England' is funded by the Department for Digital, Culture, Media and Sport.

One of its functions is to list and protect 'important' examples from more than 5000 known shipwrecks off the English coast. Dozens are so far listed as '…

English Sweating Sicknessplugin-autotooltip__plain plugin-autotooltip_bigEnglish Sweating Sickness

"The English sweating sickness caused five devastating epidemics between 1485 and 1551, England was hit hardest, but on one occasion also mainland Europe, with mortality rates between 30% and 50%. The Picardy sweat emerged about 150 years aft…

Quantum entanglementplugin-autotooltip__plain plugin-autotooltip_bigQuantum entanglement

Quantun Entanglement was first predicted by Albert Einstein, Boris Podolsky, and Nathan Rosen in 1935.

It has now been (unequivocally) experimentally demonstrated with photons, neutrinos, electrons, and even molecules. In 2019, it was announced t…

Of the (estimated) 300 million tonnes of plastic produced worldwide every year, only around 20% is currently recycled or incinerated. Much of the remaining 80% eventually ends up in the environment.

In the environment, plastics are de…

Enzyme catalysisplugin-autotooltip__plain plugin-autotooltip_bigEnzyme catalysis

Almost all metabolic processes in living cells need enzyme catalysis in order to proceed at rates fast enough to sustain life. Although enzyme processes have been investigated for many years, and more than 5000 have been identified, the extreme complex…

Epilepsyplugin-autotooltip__plain plugin-autotooltip_bigEpilepsy

"“Epilepsy is a chronic noncommunicable disease of the brain that affects around 50 million people worldwide. It is characterized by recurrent seizures, which are brief episodes of involuntary movement that may involve a part of the body (partial) or the enti…

Episalvanplugin-autotooltip__plain plugin-autotooltip_bigEpisalvan

Episalvan is a newly approved (2016) compound used to treat skin wounds such as burns and grazes, or following surgical skin grafts.

It was originally based on a traditional herbal remedy, and is an extract from the bark of the Birch tree

Erdstallsplugin-autotooltip__plain plugin-autotooltip_bigErdstalls

"“An erdstall is a type of tunnel found across Europe. They are of unknown origin but are believed to date from the Middle Ages. A variety of purposes have been theorized, including that they were used as escape routes or hiding places, but the most prominen…

Ergoloid mesylatesplugin-autotooltip__plain plugin-autotooltip_bigErgoloid mesylates

"Dihydroergotoxine mesylates, commonly known as ergoloid mesylates, has an FDA-labeled indication for use in the symptomatic therapy of age-related dementia, being employed in individuals over 60 years of age who manifest signs and symptoms of an id…

Essential Tremorplugin-autotooltip__plain plugin-autotooltip_bigEssential Tremor

"Essential tremor (ET, also referred to as benign tremor, familial tremor, or idiopathic tremor) is a progressive neurological disorder that is also the most common movement disorder. The cause of the condition is currently unknown.

Euler-Mascheroni constantplugin-autotooltip__plain plugin-autotooltip_bigEuler-Mascheroni constant

The Euler-Mascheroni constant is defined as :

{\displaystyle {\begin{aligned}\gamma =\lim _{n\to \infty }\left(-\ln n+\sum _{k=1}^{n}{\frac {1}{k}}\right)\\[5px]=\int _{1}^{\infty }\left(-{\frac {1}{x}}+{\frac {1}{\lfloor x\rfloor }}\right… Exercise addictionplugin-autotooltip__plain plugin-autotooltip_bigExercise addiction 'Addiction' to exercising is currently classed as a 'behavioural addiction' whereby a person becomes 'hooked' on the euphoria and pleasure that it provides (in some individuals). It's known that heavy exercise can generate the release hormones known… Expanding monomersplugin-autotooltip__plain plugin-autotooltip_bigExpanding monomers During polymerisation (the process in which 'monomers' crosslink chemical bonds to become 'polymers') most chemical substances physically contract in volume. This effect can cause problems in plastic moulding processes. Over the years, a variety of c… Extracellular vesiclesplugin-autotooltip__plain plugin-autotooltip_bigExtracellular vesicles Extracellular vesicles (EVs) (a.k.a.Exosomes ) are small protected packets of extracellular RNA that are produced on the cell membrane of most eukaryotic cells. They can separate from the cell wall and travel freely in any bodily fluid. Facial blood flow oscillationplugin-autotooltip__plain plugin-autotooltip_bigFacial blood flow oscillation Experimental data (starting from 1995) have shown that the volume of blood flow in human faces tends to oscillate - rising and falling once every ten seconds or so. The reasons are unknown. There are currently two theories : Fast radio burstsplugin-autotooltip__plain plugin-autotooltip_bigFast radio bursts "“Lasting only a fraction of a second yet packing a phenomenal amount of energy, FRBs are brief radio flashes of unknown origin that appear to come from random directions on the sky. Though only a handful have been documented previously, astronomers … Fast Blue Optical Transientsplugin-autotooltip__plain plugin-autotooltip_bigFast Blue Optical Transients Fast Blue Optical Transients (FBOTs) are a recently discovered (2014) class of transient astronomical objects. They have similarities with Gamma-ray bursts - but appear to be vastly more powerful. A research team from Northwestern Universi… Fibromyalgiaplugin-autotooltip__plain plugin-autotooltip_bigFibromyalgia "“After osteoarthritis, fibromyalgia is the second most common 'rheumatic' disorder. Depending on the diagnostic criteria used, the prevalence is from 2% to 8% of the population.” [...] “Patients with fibromyalgia are likely to have a history of headache… The Fine Structure Constantplugin-autotooltip__plain plugin-autotooltip_bigThe Fine Structure Constant The Fine Structure Constant, identified by the Greek letter α is a fundamental number used in quantum physics calculations. The current estimate is that it's around 0.00729735256 - or roughly 1/137. It has been called the Firefly light display synchronyplugin-autotooltip__plain plugin-autotooltip_bigFirefly light display synchrony There are many documented accounts (including video footage) of large groups of 'Fireflies' (typically beetles of the Lampyridae family) flashing their bio-luminescent lights in a synchronised display. It's not known why they have devel… Flagellaplugin-autotooltip__plain plugin-autotooltip_bigFlagella A flagellum is a lash-like movable appendage that protrudes from the cell body of many bacteria and some eukaryotic cells. Including notable examples in plants (e.g. fern spores) and even mammals (e.g. sperm cells). The primary function of a flagellum is for m… Flamencoplugin-autotooltip__plain plugin-autotooltip_bigFlamenco The earliest documented reference to the Flamenco tradition goes back to the late eighteenth century. Its development since then has been extensively documented, but the origins of the tradition are unknown. "There is no doubt that Flamenco is rooted in vari… Fleroviumplugin-autotooltip__plain plugin-autotooltip_bigFlerovium The existence of element Flerovium (previously known as Ununquadium) (element 114) was confirmed in January 2009 at Berkeley, US. It appears to behave as the first superheavy element that shows noble-gas-like properties - possibly due to relativistic effects. Flint formationplugin-autotooltip__plain plugin-autotooltip_bigFlint formation Flint is a ubiquitous sedimentary cryptocrystalline form of quartz. It is found across the world, in regions that have sedimentary rocks, such as chalks and limestones. It mainly appears as 'nodules' which are usually grey, black, green, white or brown… Flowering plants evolutionplugin-autotooltip__plain plugin-autotooltip_bigFlowering plants evolution The evolutionary pathways that produced the flowering plants (the Angiosperms) have been studied for at least 140 years. The flowering plants appear very suddenly (geologically speaking) in the fossil record, at around 100 million years ago.… Influenzaplugin-autotooltip__plain plugin-autotooltip_bigInfluenza This article, in the Proposed Content section, has no reference links, and is flagged for removal. ‘Flu is contagious. It can be transmitted by touching an infected person – e.g. by a handshake – or by sneezing / coughing etc etc. But there has never been an… Fluoxetineplugin-autotooltip__plain plugin-autotooltip_bigFluoxetine Fluoxetine is a Selective Serotonin Reuptake Inhibitor (SSRI) used in the treatment of Major Depressive Disorderand Obsessive-Compulsive disorder etc.. It's marketed under the trade names Prozac™, Sarafem™, Fontex™ etc. SSRIs are believed to act by inhibiti… Flyby anomaliesplugin-autotooltip__plain plugin-autotooltip_bigFlyby anomalies "The flyby anomaly is a discrepancy between current scientific models and the actual increase in speed (i.e. increase in kinetic energy) observed during a planetary flyby (usually of Earth) by a spacecraft. In multiple cases, spacecraft have been obser… Immune tolerance in pregnancyplugin-autotooltip__plain plugin-autotooltip_bigImmune tolerance in pregnancy Why doesn't an expectant mother's immune system damage her growing baby - since it has 'foreign' DNA? This fundamental phenomenon has yet to be fully explained. "“During pregnancy, the maternal immune system is exposed to a major chall… Four Color Theoremplugin-autotooltip__plain plugin-autotooltip_bigFour Color Theorem Note: This theorem is widely regarded as having been solved. As of Apr. 2019, this entry is now moved to the 'Deprecated' section. See : Formal Proof—The Four-Color Theorem Notices of the AMS Volume 55, Number 11. The original text of the ar… Fractional quantum Hall effect (FQHE)plugin-autotooltip__plain plugin-autotooltip_bigFractional quantum Hall effect (FQHE) The 1998 the Nobel Prize in Physics was awarded to Robert Laughlin, Horst Störmer, and Daniel Tsui for the discovery and explanation of the fractional quantum Hall effect (FQHE). Their work, performed using gallium arsenide hetero… Free willplugin-autotooltip__plain plugin-autotooltip_bigFree will Do we have free will? "“... much of the debate about free will centers around whether we human beings have it, yet virtually no one doubts that we will to do this and that. ” Source : Stanford Encyclopedia of Philosophy" Most people feel that they definite… 'Frock' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Frock' etymology "Frock (n.) mid-14c., from Old French froc “a monk's habit; clothing, dress” (12c.), which is of unknown origin; perhaps from Frankish hrok or some other Germanic source (compare Old High German hroc “mantle, coat;” Old Norse rokkr, Old English rocc,… Frog tongue adhesionplugin-autotooltip__plain plugin-autotooltip_bigFrog tongue adhesion "“Frogs are well known to capture fast-moving prey by flicking their sticky tongues out of the mouth. This tongue projection behaviour happens extremely fast which makes frog tongues a biological high-speed adhesive system. The processes at the in… 'Frying Pans' (artefacts)plugin-autotooltip__plain plugin-autotooltip_big'Frying Pans' (artefacts) 'Frying Pans' is the name given to a very specific set of archaeological artefacts from the Cyclades, Crete, and the Aegean Islands (and possibly mainland Greece). They are usually 20 to 28 cm in diameter, are highly decorated, and have a vari… Fujiwara–Moritani reactionplugin-autotooltip__plain plugin-autotooltip_bigFujiwara–Moritani reaction Technical description : "[...] the Fujiwara–Moritani reaction is a type of cross coupling reaction where an aromatic C-H bond is directly coupled to an olefinic C-H bond, generating a new C-C bond. This reaction is performed in the presence… Fusiform Gyrusplugin-autotooltip__plain plugin-autotooltip_bigFusiform Gyrus First named in 1854, the Fusiform Gyrus is a brain-area found in hominoids (inc. humans), the function of which is still mostly unknown. "“The fusiform gyrus, also known as the lateral occipitotemporal gyrus, is part of the temporal lobe and occipital … Gabapentinplugin-autotooltip__plain plugin-autotooltip_bigGabapentin Gabapentin, sold under the brandnames Gralise, Gabarone, Fanatrex, Neurontin (and mmany others) was discovered in the 1970s, and was first used as a muscle relaxant and painkiller. In the US alone, it currently has more than 40 million prescriptions per yea… Generalised Anxiety Disorder (GAD)plugin-autotooltip__plain plugin-autotooltip_bigGeneralised Anxiety Disorder (GAD) "Generalised anxiety disorder is a persistent and common disorder, in which the patient has unfocused worry and anxiety that is not connected to recent stressful events, although it can be aggravated by certain situations. This disor… Galaxies (definition of)plugin-autotooltip__plain plugin-autotooltip_bigGalaxies (definition of) "“What exactly is a galaxy? Surprising as it may sound, astronomers don't have an answer to this fundamental question. There's no agreement on when a collection of stars stops being a cluster and starts being something more. Galaxy formationplugin-autotooltip__plain plugin-autotooltip_bigGalaxy formation There are currently two (mutually exclusive) theories regarding the formation of galaxies, which according to current models, all have a supermassive Black Hole at their centre. 1) The galaxy formed around a pre-existing Black Hole which was sufficie… Galaxy Rotation Problemplugin-autotooltip__plain plugin-autotooltip_bigGalaxy Rotation Problem "The rotation curve of a disc galaxy (also called a velocity curve) is a plot of the orbital speeds of visible stars or gas in that galaxy versus their radial distance from that galaxy's centre. It is typically rendered graphically as a plot, a… Gamma-ray burstsplugin-autotooltip__plain plugin-autotooltip_bigGamma-ray bursts Gamma-ray bursts (which were first discovered by satellites originally intended to scan for nuclear weapon detonations) probably have multiple sources. They range from bursts of ten milliseconds to several hours, and also have differing energy levels. … Ganser syndromeplugin-autotooltip__plain plugin-autotooltip_bigGanser syndrome In 1897 Dr Sigbert Ganser compiled a report about several cases of a previously undescribed psychological condition, in which patients gave approximate answers to questions, had a clouding of consciousness, somatic conversion symptoms and hallucinations… Gecko pad adhesionplugin-autotooltip__plain plugin-autotooltip_bigGecko pad adhesion Geckos (small reptiles of the family Gekkonidae ) can walk upside down on almost any surface due to the microscopic hairs, called setae, on their toe pads. Since the discovery of the molecular Van der Waals Force - which causes very closely aligned… Gemfibrozilplugin-autotooltip__plain plugin-autotooltip_bigGemfibrozil Gemfibrozil - sold under brand name of Lopid, Jezil and others - is used to treat abnormal blood lipid levels. Currently around 4 million prescriptions per year in the US alone. Its mechanism of action is, to date, unknown. "The exact mechanism of action … General Anaestheticsplugin-autotooltip__plain plugin-autotooltip_bigGeneral Anaesthetics A general anaesthetic is a drug that brings about a reversible loss of consciousness. In formal use since 1842 - with the first public demonstration of the use of Diethyl ether to carry out surgery. (Though it's likely that alcohol, another chemi… Genome sizeplugin-autotooltip__plain plugin-autotooltip_bigGenome size The size of the genome (which can be said to be the amount of DNA in an organism's genes) varies enormously from one species to another. The smallest size, for viruses, varies from 2 thousand base-pairs to over a million. Humans have about 3 billion (formi… Geobatteriesplugin-autotooltip__plain plugin-autotooltip_bigGeobatteries Geobatteries (also known as 'Self Potential' (SP) anomalies), are widespread measurable electrical differences in naturally-occurring geological formations. There have been several proposals to explain how they might come about - it's likely that there ar… Earth’s magnetic fieldplugin-autotooltip__plain plugin-autotooltip_bigEarth’s magnetic field Without the magnetic field, high energy radiation from space would affect the Earth's upper atmosphere much more dramatically – and high-energy radiation reaching the surface would be far higher. The levels of radiation without Gestational diabetesplugin-autotooltip__plain plugin-autotooltip_bigGestational diabetes "Gestational diabetes mellitus (GDM) is defined as glucose intolerance of various degrees that is first detected during pregnancy. GDM is detected through the screening of pregnant women for clinical risk factors and, among at-risk women, testing … Giant Virusesplugin-autotooltip__plain plugin-autotooltip_bigGiant Viruses Giant viruses are a recently-discovered (2003) group of viruses, some of which have a genome larger than that of many bacteria. Their evolutionary history is a mystery. "“The discovery of giant viruses blurred the sharp division between viruses and cell… Giraffe neck evolutionplugin-autotooltip__plain plugin-autotooltip_bigGiraffe neck evolution The evolution of the extremely elongated neck of giraffes, which can be up to 2–2.4m in length, has been the subject of intense debate since the time of Darwin. "“The 'competing browsers hypothesis' was originally suggested by Charles Darwin an… Glacier Miceplugin-autotooltip__plain plugin-autotooltip_bigGlacier Mice 'Glacier Mice' were first described (and named) by Icelandic researcher Jón Eyþórsson in a 1951 letter to the Journal of Glaciology. They are found on the surface of glaciers, and are typically 7 to 10cm in diameter, being composed of small stones covered… Glassesplugin-autotooltip__plain plugin-autotooltip_bigGlasses Glasses are amorphous (non-crystalline) solid materials (most commonly silicates). The nature of the glass transition between a fluid or regular solid and a glassy phase is poorly understood. According to (late) Professor Philip Warren Anderson : "“The deepe… Glioblastomasplugin-autotooltip__plain plugin-autotooltip_bigGlioblastomas Glioblastomas are the second most prevalent form of brain cancer (after Meningiomas). The cancers are malignant and highly aggressive, and are hard to treat effectively (either with drugs, surgery of radiotherapy). It's estimated that more than 20,000 cas… Glycogen Body (birds)plugin-autotooltip__plain plugin-autotooltip_bigGlycogen Body (birds) "A glycogen body is an oval structure in the spinal cord of birds that is made of specialized cells that contain large amounts of glycogen. Housed within the synsacrum, the function of this structure is not known, but it does not seem to be relat… Gödel's incompleteness theoremsplugin-autotooltip__plain plugin-autotooltip_bigGödel's incompleteness theorems "“Gödel proved that, within any axiomatic framework for mathematics there are mathematically true statements that we will never be able to prove are true within that framework.” Source: Marcus du Sautoy, What We Cannot Know: Explorati… Göbekli Tepeplugin-autotooltip__plain plugin-autotooltip_bigGöbekli Tepe The archaeological site in Anatolia, Turkey, called Göbekli Tepe (map) is now a UNESCO World Heritage site. It came to the attention of archaeological scholars in 1963, and is estimated to date from around 12,000 years ago. Its construction is reckoned to … Gold Catalysisplugin-autotooltip__plain plugin-autotooltip_bigGold Catalysis "Catalysis by gold has rapidly become a hot topic in chemistry, with a new discovery being made almost every week. Gold is equally effective as a heterogeneous or a homogeneous catalyst and in this Review we attempt to marry these two facets to demonstr… Goldbach's conjectureplugin-autotooltip__plain plugin-autotooltip_bigGoldbach's conjecture Goldbach's conjecture is one of the oldest and best-known unsolved problems in number theory and all of mathematics. It states: Every even integer greater than 2 can be expressed as the sum of two primes. The conjecture has been shown to hold f… The origins of Golfplugin-autotooltip__plain plugin-autotooltip_bigThe origins of Golf "“The origin of golf has long been debated. Some historians trace the sport back to the Roman game of paganica, which involved using a bent stick to hit a wool- or feather-stuffed leather ball. According to one view, paganica spread throughout seve… Golgi Apparatusplugin-autotooltip__plain plugin-autotooltip_bigGolgi Apparatus The Golgi Apparatus (a.k.a the Golgi Body and Golgi Complex) is an 'oganelle' (small component) found in almost all cells that have a nucleus (i.e. eukaryotic cells). It packages 'vesicles' (i.e. small packages of protein wrapped in a fatty membrane) a… Grave's diseaseplugin-autotooltip__plain plugin-autotooltip_bigGrave's disease "Graves’ disease is an autoimmune disease that leads to a generalized overactivity of the entire thyroid gland (hyperthyroidism). It is the most common cause of hyperthyroidism in the United States. It is named after Robert Graves, an Irish physician, … The Gravitational constantplugin-autotooltip__plain plugin-autotooltip_bigThe Gravitational constant The gravitational attraction between two objects is dependent on the mass of the objects, the distance between them, and the gravitational constant (G). The masses and distance can vary, but the constant, as the name implies, is always a fix… Gravitational singularitiesplugin-autotooltip__plain plugin-autotooltip_bigGravitational singularities "A gravitational singularity, spacetime singularity or simply singularity is a location in spacetime where the mass and gravitational field of a celestial body is predicted to become infinite by general relativity in a way that does not dep… Gravity sensing in plantsplugin-autotooltip__plain plugin-autotooltip_bigGravity sensing in plants Specialist cells (Statocytes) in plants are able to sense gravity. Thus shooting tips grow upwards, against the Earth's gravitational field, while roots grow downwards. Statocytes are located in the starch parenchyma cells near vascular tissue… Gravityplugin-autotooltip__plain plugin-autotooltip_bigGravity Although three of the four (known) fundamental forces have been unified by one paradigm called the Standard Model, Gravity remains outside. Like General Relativity, Gravity appears, so far, not to fit. This doesn't necessarily mean that Standard Model has fai… The Great Depression (causes)plugin-autotooltip__plain plugin-autotooltip_bigThe Great Depression (causes) "The Great Depression was a severe worldwide economic depression that took place mostly during the 1930s, beginning in the United States. The timing of the Great Depression varied across the world; in most countries, it started in 1929 an… Green teaplugin-autotooltip__plain plugin-autotooltip_bigGreen tea A 2006 study, published in the Journal of the American Medical Association, found that : "“Green tea consumption is associated with reduced mortality due to all causes and due to cardiovascular disease but not with reduced mortality due to cancer. grotthuss_mechanism Growing painsplugin-autotooltip__plain plugin-autotooltip_bigGrowing pains "Growing pains are typically non-articular, intermittent bilateral aches or pains in the legs that occur in the evening or at night in children aged 3-12 years. They are not associated with limping or limited mobility and do not involve the joints (all o… Guillain-Barré syndromeplugin-autotooltip__plain plugin-autotooltip_bigGuillain-Barré syndrome "“Guillain-Barré syndrome is the most common and most severe acute paralytic neuropathy, with about 100 000 people developing the disorder every year worldwide. Under the umbrella term of Guillain-Barré syndrome are several recognisable variant… Hair folliclesplugin-autotooltip__plain plugin-autotooltip_bigHair follicles "“The hair follicle has been an object of intense research for more than 70 years and a quick search on PubMed now retrieves almost 8000 articles. With such a vast collection of published results, one might think that mos… Hair greying (canities)plugin-autotooltip__plain plugin-autotooltip_bigHair greying (canities) "Hair greying (referred to during ageing as ‘canities’) is one of the earliest and most visible indicators of ageing in humans. The social significance of greying persists across cultures, geographical locations, and ethnicities, alongside a no… Handednessplugin-autotooltip__plain plugin-autotooltip_bigHandedness "“Although the percentage varies by culture, in Western countries 85 to 90 percent of people are right-handed and 10 to 15 percent of people are left-handed. Mixed-handedness (preferring different hands for different tasks) and ambidextrousness (the ability… Hangoverplugin-autotooltip__plain plugin-autotooltip_bigHangover "“Alcohol hangover is characterized by adverse physical and mental effects that occur the next morning after the intake of toxic doses of alcohol. This phenomenon is a very frequent experience among alcohol-consuming people and it has been associated to high … Hangover Resistanceplugin-autotooltip__plain plugin-autotooltip_bigHangover Resistance A proportion of adults are (or claim to be) 'immune' from developing hangovers after heavy alcohol consumption. Estimates vary as to the prevalence of 'hangover resistance'. A 2008 study from the US put the figure at around 23 percent. A 2017 stud… High-altitude pulmonary edema (HAPE)plugin-autotooltip__plain plugin-autotooltip_bigHigh-altitude pulmonary edema (HAPE) High-altitude pulmonary edema (HAPE) is one of the dangerous symptoms of altitude sickness. It's the major cause of death related to high-altitude exposure, with a high mortality rate in the absence of adequate emergency treatment. Happiness and ageingplugin-autotooltip__plain plugin-autotooltip_bigHappiness and ageing In general, people tend to be 'happiest' (or at least say they are) between the ages of 60 > 75. The effect, which various research groups have now verified in more than 70 countries - has yet to be explained. Other researchers say the effect is t… Heat and Human Aggressionplugin-autotooltip__plain plugin-autotooltip_bigHeat and Human Aggression It's suggested that increased ambient temperatures tend to increase aggressive behavior in humans. There is no generally agreed explanation. See: ‘Ambient Temperature and Horn Honking : A Field Study of the Heat/Aggression Relationship’ in: … Heat painplugin-autotooltip__plain plugin-autotooltip_bigHeat pain The intense pain associated with touching, or being touched by, an object that is damagingly hot, is initiated via specialist cells in the skin called TRPV1 cells (Transient Receptor Potential cation channel subfamily V member 1). They are a sub-category of '… Origin of the heavier elementsplugin-autotooltip__plain plugin-autotooltip_bigOrigin of the heavier elements Since Big Bang Theory doesn't provide an explanation for the origin of the heavier elements which make up most of the Earth and the life on it - many cosmological theorists contend that they may have instead formed in supernovae explosion… The Heliopauseplugin-autotooltip__plain plugin-autotooltip_bigThe Heliopause The heliopause is the region is space where the influence of the solar wind and interstellar wind are in equilibrium - in other words where 'pressure' from matter originating from the Sun and matter originating from the rest of the galaxy cancel each oth… Heller's syndromeplugin-autotooltip__plain plugin-autotooltip_bigHeller's syndrome Heller's syndrome, also known as Childhood Disintegrative Disorder (CDD), is a rare Pervasive Developmental Disorder (PDD) which involves regression of developmental ability in language, social function and motor skills. It affects around 140,000 chi… HELLP syndromeplugin-autotooltip__plain plugin-autotooltip_bigHELLP syndrome "HELLP syndrome is a life-threatening condition that can potentially complicate pregnancy. It is named for 3 features of the condition: Hemolysis, Elevated Liver enzyme levels, and Low Platelet levels. It typically occurs in the last 3 months of pregnan… Hemorrhoidsplugin-autotooltip__plain plugin-autotooltip_bigHemorrhoids Hemorrhoids (alt. haemorrhoids) are the most common anorectal disorder and are frequently seen in primary care clinics, emergency wards, gastroenterology units, and surgical clinics. More than half of all people will at some point develop symptomatic hemorr… Henry's pocketplugin-autotooltip__plain plugin-autotooltip_bigHenry's pocket Henry's pocket - a.k.a. the Cutaneous Marginal Pouch - is a fold of skin found on the outer ear (pinnae) of many mammals. Weasels, bats and some cats and dogs have prominent versions of it. And there are vestigial traces in the human ear. Hepatitis E in pregnancyplugin-autotooltip__plain plugin-autotooltip_bigHepatitis E in pregnancy Hepatitis E is a severe, acute viral disease which causes liver damage. In most patients, it normally 'self resolves' - and there is no specific effective treatment. It's widespread across the world, and is currently estimated to be responsible… Heritable primingplugin-autotooltip__plain plugin-autotooltip_bigHeritable priming Heritable Priming is the name given to the process in which organisms are able to pass-on stress protection from the parent generation to the siblings. The 'stress' can be physical (one of the original studies investigated how plants' lack of water c… Heroin overdosesplugin-autotooltip__plain plugin-autotooltip_bigHeroin overdoses "“Heroin overdose deaths in the Unites States more than tripled from 2010 to 2014, reaching almost 11,000 per year. Despite the use of the term 'overdose,' many of these victims died after self-administering an amount of opiate that would not be expec… Hessdalen lightsplugin-autotooltip__plain plugin-autotooltip_bigHessdalen lights The Hessdalen Lights are unexplained airborne lights observed in the Hessdalen valley in rural central Norway. They first appeared in 1981, and at the peak of activity, there were around 20 reports each week. Currently, there are fewer events, but the … Hibernationplugin-autotooltip__plain plugin-autotooltip_bigHibernation "“Hibernation is an adaptive strategy characterized by a drastic suppression of metabolism, activity and body temperature that allows animals to survive during periods with little or no food availability; hibernation is widespread among mammals. Two types … High Energy Neutrino Burstsplugin-autotooltip__plain plugin-autotooltip_bigHigh Energy Neutrino Bursts In 2013, the IceCube Astronomical Observatory in Antarctica announced (via the journal Science) the discovery of ultra high energy neutrinos coming from deep space. "“The 28 high-energy neutrinos were found in data collected by the IceCube… Hindenburg disasterplugin-autotooltip__plain plugin-autotooltip_bigHindenburg disaster The pioneering passenger airship Hindenburg caught fire on May 6, 1937, killing 36 - effectively putting to an end ideas for hydrogen-filled passenger airships. The exact cause of the fire is unknown. ref Wikipedia Note: This article is flagged … Hippocampal sclerosisplugin-autotooltip__plain plugin-autotooltip_bigHippocampal sclerosis Hippocampal sclerosis is a progressive degenerative disease which leads to loss of neurons in the brain's Hippocampal region. It was first described in the 1880s. Its diagnosis is often missed as the symptoms in the early stages (dementia etc) are… Hodgkin lymphomaplugin-autotooltip__plain plugin-autotooltip_bigHodgkin lymphoma "Hodgkin lymphoma is caused by a change in the DNA of a B-cell lymphocyte. This mutation causes a large number of abnormal and oversized B cells to accumulate in the lymphatic system, and, over time, spread to other organs. It is not clear what causes… Holesplugin-autotooltip__plain plugin-autotooltip_bigHoles For many philosophers, the scholarly debate around holes began in earnest in 1970, with Lewis and Lewis’s now classic article for the Australasian Journal of Philosophy (48: 206–212.) The authors presented their paper in a highly unusual format - that of an ima… Homerplugin-autotooltip__plain plugin-autotooltip_bigHomer "“Homer (Ancient Greek: Ὅμηρος [hómɛːros], Hómēros) is best known as the author of the Iliad and the Odyssey. He was believed by the ancient Greeks to have been the first and greatest of the epic poets. Author of the first known literature of Europe, he is centr… Homochiralityplugin-autotooltip__plain plugin-autotooltip_bigHomochirality "“Symmetry is a fundamental aspect of nature. For example, certain molecules exist in two forms which are symmetrical mirror images of each other. They are called chiral molecules. Common chemical synthesis generally produces equal amounts of the two for… Honeycomb grouperplugin-autotooltip__plain plugin-autotooltip_bigHoneycomb grouper Note This is an example page of an item that has been included, but is awaiting full details Honeycomb grouper The Honeycomb grouper, one of the smaller fish species in the Epinephelus genus, sometimes undergoes spontaneous sex changes. Reasons unknown. ref. Hot Flushes (in menopause)plugin-autotooltip__plain plugin-autotooltip_bigHot Flushes (in menopause) Most women will experience hot flushes ('flashes' US) when going through the menopause. They're often described as a sudden feeling of heat that seems to come from nowhere and spreads throughout the body. It's assumed that they are in some w… High Temperature Superconductivityplugin-autotooltip__plain plugin-autotooltip_bigHigh Temperature Superconductivity The first high-temperature superconductor was discovered in 1986 by IBM researchers Karl Müller and Johannes Bednorz, for which they were awarded the Nobel Prize in Physics in 1987. Since then many other materials with even higher sup… 'Huguenot' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Huguenot' etymology The 16th century Huguenots were French Protestants (puritans) who held to the Reformed, or Calvinist, tradition of Protestantism. The origin of the word itself is unknown. According to Roche 'The Days of the Upright, A History of the Huguenots' The Human Chinplugin-autotooltip__plain plugin-autotooltip_bigThe Human Chin "“Although modern humans are considered to be morphologically distinct from other living primates because of our large brains, dexterous hands, and bipedal gait, all of these features are found among extinct hominins. The chin, however, appears to be a … Human Evolutionplugin-autotooltip__plain plugin-autotooltip_bigHuman Evolution "“[...] over the past 15 years, almost every part of our story, every assumption about who our ancestors were and where we came from, has been called into question. The new insights have some unsettling implications for how long we have walked the eart… Human population limitsplugin-autotooltip__plain plugin-autotooltip_bigHuman population limits "Models and estimates of Earth’s human carrying capacity vary widely and assume, rather than solve for, binding environmental constraints (the process or resource in shortest supply relative to human biological needs). The binding constraint, a… Human running gaitplugin-autotooltip__plain plugin-autotooltip_bigHuman running gait Humans tend to run with arms bent at an acute angle. The reasons are unclear. A 2019 study published in the Journal of Experimental Biology found that there could be an energy advantage for walking with elbows slightly bent - but was unable to accoun… Humour evolutionplugin-autotooltip__plain plugin-autotooltip_bigHumour evolution "There are several reasons to suppose humor and laughter could be evolutionarily adaptive. [...] the complexity of humor implicates an established genetic substrate that in turn could suggest evolutionary adaptiveness. Given that even a simple joke ca… Hydrogen embrittlementplugin-autotooltip__plain plugin-autotooltip_bigHydrogen embrittlement Hydrogen embrittlement is the name given to the process in which metals ( e.g steel, copper, vanadium, nickel, titanium etc) become brittle when exposed to hydrogen. It's of crucial concern in metal manufacturing where the embrittlement can cause… Hypertensionplugin-autotooltip__plain plugin-autotooltip_bigHypertension Only 5 -10% of cases of hypertension have causes which can be clearly identified (e.g. narrowing of the arteries). Put another way, of those patients who have been identified as having abnormally high blood pressure, physicians will not be able to pinpoin… Hypervalent moleculesplugin-autotooltip__plain plugin-autotooltip_bigHypervalent molecules "A hypervalent molecule (the phenomenon is sometimes colloquially known as expanded octet) is a molecule that contains one or more main group elements apparently bearing more than eight electrons in their valence shells. Phosphorus pentachloride … Hypnic jerksplugin-autotooltip__plain plugin-autotooltip_bigHypnic jerks Hypnic jerks (a.k.a. Hypnagogic jerks, sleep starts, sleep twitches, myoclonic jerks, night starts etc) are brief and sudden involuntary muscle contractions (twitches) which happen as a person is beginning to fall asleep. They can be severe enough to wake … Hypnosisplugin-autotooltip__plain plugin-autotooltip_bigHypnosis "Hypnosis is a human condition involving focused attention, reduced peripheral awareness, and an enhanced capacity to respond to suggestion. There are competing theories explaining hypnosis and related phenomena. Altered state theories see hypnosis as an alte… Irritable bowel syndrome (IBS)plugin-autotooltip__plain plugin-autotooltip_bigIrritable bowel syndrome (IBS) "“The most common condition seen in gastrointestinal outpatient clinics is irritable bowel syndrome (IBS), which has a prevalence rate of 14-24% in women and 5-19% in men. [...] There is no known structural or anatomical explanation that… Chloroquineplugin-autotooltip__plain plugin-autotooltip_bigChloroquine Chloroquine (closely related to the naturally-occurring Quinine which has been used for centuries to treat and prevent malaria) was discovered in 1934 by Hans Andersag. and is on the World Health Organization's List of Essential Medicines. Linear Elamiteplugin-autotooltip__plain plugin-autotooltip_bigLinear Elamite So far, 22 examples of Linear Elamite texts have been found. The writings form part of a Bronze Age system used in Elam (now part of modern-day Iran). It appears to have been in use for a brief period during the last quarter of the 3rd millennium BC. It… Immunological toleranceplugin-autotooltip__plain plugin-autotooltip_bigImmunological tolerance Immunological tolerance is the ability of an individual's immune system to ignore “self” while reacting to “non-self” organisms and substances. The system is extremely complex, and needs to somehow set a balance between being able to accurately… Indus scriptplugin-autotooltip__plain plugin-autotooltip_bigIndus script "The Indus script (also known as the Harappan script) is a corpus of symbols produced by the Indus Valley Civilization. Most inscriptions containing these symbols are extremely short, making it difficult to judge whether or not these symbols constituted a… Infant Rockingplugin-autotooltip__plain plugin-autotooltip_bigInfant Rocking "“People tend to fall asleep when gently rocked or vibrated. Experimental studies have shown that rocking promotes sleep in humans and mice. However, the mechanisms underlying the phenomenon are not well understood.“ Source: Cell Reports, vol. 33, issue… Infinityplugin-autotooltip__plain plugin-autotooltip_bigInfinity If a mathematician wants to explore infinity, there are many options - for example by calculating pi, or the square root of 2, or dividing any number by 0. For philosophers, the concept of infinity is fraught with enigmas. Are some infinities larger than oth… Cosmological inflationplugin-autotooltip__plain plugin-autotooltip_bigCosmological inflation Using mathematics constrained by the ‘Standard Model’ (the laws of physics as currently understood) it’s not possible to create coherent mathematical solutions which account for the evolution of the universe – from the Influenza seasonalityplugin-autotooltip__plain plugin-autotooltip_bigInfluenza seasonality The incidence of Influenza ('flu) is tightly linked to the seasons. In temperate climates, it's thought that the disease exists at low levels during the warmer Summer months, and then dramatically peaks during the Winter. The reasons for this 'se… Inner speechplugin-autotooltip__plain plugin-autotooltip_bigInner speech "When people reflect upon their own inner experience, they often report that it has a verbal quality (Baars, 2003). Also referred to as verbal thinking, inner speaking, covert self-talk, internal monologue, and internal dialogue, inner speech Insect flight evolutionplugin-autotooltip__plain plugin-autotooltip_bigInsect flight evolution "Sometime in the Carboniferous Period, some 350 to 400 million years ago, when there were only two major land masses, insects began flying. How and why insect wings developed is not well understood, largely due to the scarcity of appropriate fo… Instinct and Inheritanceplugin-autotooltip__plain plugin-autotooltip_bigInstinct and Inheritance Complex behaviour patterns can be learned, but (it appears that) they can also be inherited. Example 1 The female Common Cuckoo (Cuculus canorus) is a so-called 'brood parasitic' - in that it lays its eggs in the nests of other birds. This ca… Intelligenceplugin-autotooltip__plain plugin-autotooltip_bigIntelligence "“Numerous definitions of and hypotheses about intelligence have been proposed since before the twentieth century, with no consensus reached by scholars.” Source wikipedia" Despite the lack of an agreed definition, tests of IQ (Intelligence Quotients) … Intelligence inheritanceplugin-autotooltip__plain plugin-autotooltip_bigIntelligence inheritance Note: There is currently no formal definition of Intelligence Theories regarding the inheritance of human intelligence are highly controversial, nevertheless, it's widely believed that various aspects of intelligence can, to some extent, be in… Intergalactic starsplugin-autotooltip__plain plugin-autotooltip_bigIntergalactic stars Until 1997 it was assumed that all stars belong to galaxy clusters. In other words 'bound' by the gravitational field of a galaxy. It is now confirmed that there are very many stars which are totally independent of any galaxy. More than 600 have be… Interstellar cometsplugin-autotooltip__plain plugin-autotooltip_bigInterstellar comets "The question of interstellar comets is a fascinating and difficult topic since we are discussing a population of objects which we have never seen, and perhaps will never see. Yet we know that interstellar comets must exist. The Solar System Interstitial cystitisplugin-autotooltip__plain plugin-autotooltip_bigInterstitial cystitis Interstitial Cystitis (IC), also known as Bladder Pain Syndrome (BPS), is a type of chronic pain that affects the bladder. The cause is unknown. But contributing factors might include autoimmune problems, neurological problems, infection, allergi… Intraoperative Awarenessplugin-autotooltip__plain plugin-autotooltip_bigIntraoperative Awareness Intraoperative Awareness (a.k.a. Anesthesia awareness) occurs as a complication during general anesthesia, where the intended state of complete unconsciousness is not maintained throughout the whole procedure. "“The incidence of this anesthes… Ionised airplugin-autotooltip__plain plugin-autotooltip_bigIonised air "“Several experimental human studies on air ion exposure and mood ratings have been published throughout the years. While their evidence is inconsistent, the findings have increased awareness of mood alterations possibly associated with such exposure. Ions… Irrational numbersplugin-autotooltip__plain plugin-autotooltip_bigIrrational numbers Note: This item is an example of a special case - Known Unknowables Irrational numbers An irrational number is a real number that cannot be expressed as a ratio of integers, i.e. as a fraction. Put another way, it can never be specified with absolute accuracy. Isotretinoinplugin-autotooltip__plain plugin-autotooltip_bigIsotretinoin Isotretinoin (13-cis-retinoic acid) is a medication primarily used to treat severe acne. It's also occasionally used to help prevent certain skin cancers such as squamous-cell carcinoma, and (rarely) in the treatment of some other cancers. It's sold under … Isthmian scriptplugin-autotooltip__plain plugin-autotooltip_bigIsthmian script The Isthmian script (a.k.a. La Mojarra script and the Epi-Olmec script) is a Mesoamerican writing system which was in use in the Tehuantepec area (of current-day Mexico). The time of its use is not known - perhaps between 500 BCE and 500 CE. Jetstream migrationplugin-autotooltip__plain plugin-autotooltip_bigJetstream migration Jet streams are permanent, narrow bands of fast moving (100 > 200 km/h) high altitude (9–12 km above sea level) meandering air currents which flow around the globe in both hemispheres. Their positioning and power is very significantly important to … Jiahu symbolsplugin-autotooltip__plain plugin-autotooltip_bigJiahu symbols "Early Neolithic graves at Jiahu, Henan Province, China, include tortoise shells which are incised with signs – some of which anticipate later Chinese characters and may be intended as words. Is this the earliest writing? The authors decide rather that t… Juggler sequencesplugin-autotooltip__plain plugin-autotooltip_bigJuggler sequences Juggler sequences were first proposed by American mathematician and author Clifford A. Pickover. They take the form :{\displaystyle a_{k+1}={\begin{cases}\left\lfloor a_{k}^{\frac {1}{2}}\right\rfloor {\mbox{if }}a_{k}{\mbox{ is even}}\\\\\left\l…

Jupiter - atmospheric heatingplugin-autotooltip__plain plugin-autotooltip_bigJupiter - atmospheric heating

The low to mid-latitudes of Jupiter's atmosphere have been found to have a temperature of around 800ºK - which is 600ºK warmer than can be accounted for by solar heating. The apparent anomaly was discovered in the mid 1970's (See:

Jupiter - radio auroraplugin-autotooltip__plain plugin-autotooltip_bigJupiter - radio aurora

Chance observations in 1955 logged strong radio frequency oscillations from Jupiter between the Kilometric (1000s metres) and Decametric (10s metres) wavebands. NASA's Juno spacecraft scanned Jupiter in late 2016 and made recordings of the emissi…

Kawasaki diseaseplugin-autotooltip__plain plugin-autotooltip_bigKawasaki disease

"“Kawasaki disease (KD), also known as Kawasaki syndrome, is a serious illness characterized by inflammation of blood vessels throughout the body that primarily affects young children and infants. Kawasaki disease is the leading cause of acquired hear…

The Kelvin problem (3-D packing)plugin-autotooltip__plain plugin-autotooltip_bigThe Kelvin problem (3-D packing)

In 2 dimensions, the most efficient packing mechanism is an array of hexagons - a honeycomb. In 1887, William Thomson (Lord Kelvin) asked the question 'What is the most efficient 3-D packing system?“

See (the original paper) :

Keratoconusplugin-autotooltip__plain plugin-autotooltip_bigKeratoconus

"Keratoconus is an eye (ocular) disorder characterized by progressive thinning and changes in the shape of the cornea. The cornea is the thin, clear outer layer of the eye and is normally dome-shaped. Slowly progressive thinning of the cornea causes a cone…

Ketamine (treatment for depression)plugin-autotooltip__plain plugin-autotooltip_bigKetamine (treatment for depression)

The use of Ketamine to treat depression was formally investigated in a 2006 report for JAMA Psychiatry. A team based at the US National Institute of Mental Health (NIMH) in Bethesda, Maryland, found that :

"“Robust and rapid anti…

Ketogenic dietplugin-autotooltip__plain plugin-autotooltip_bigKetogenic diet

"The ketogenic diet remains a valuable therapeutic option for patients with intractable epilepsy. Clinical aspects of the diet's success may provide insights into epileptogenesis and anticonvulsant action. The diet's efficacy has been established primar…

Khitan scriptsplugin-autotooltip__plain plugin-autotooltip_bigKhitan scripts

The Khitan people, who dominated a large chunk of Manchuria (an area mostly in Northeast China today). between 916 and 1125 AD, used two different scripts - the 'large script', which came into use in about 920 AD, and the 'small script', which was repute…

Kidney stonesplugin-autotooltip__plain plugin-autotooltip_bigKidney stones

"“The mechanism of kidney stone formation is not well understood.” [...] “Further studies are necessary to fully elucidate the mechanisms of stone formation in patients with nephrolithiasis.”

Source: Minerva Urol Nefrol. 2016"

This paper in Biochemical…

Kimura diseaseplugin-autotooltip__plain plugin-autotooltip_bigKimura disease

"“Kimura disease is a rare benign chronic inﬂammatory disease that usually involves deep subcutaneous tissue and lymph nodes of the head and neck region with frequent regional lymphadenopathy or salivary gland enlargement. Other sites of involvement inc…

King Arthurplugin-autotooltip__plain plugin-autotooltip_bigKing Arthur

The authenticity of the English 'King' is debated by researchers. The first written mention of Arthur is from 829 AD, some 300 years after he was said to have existed.

The debate continues …

Kissingplugin-autotooltip__plain plugin-autotooltip_bigKissing

Some human cultures (allegedly) don’t practice kissing - it is nevertheless a widespread activity. Wikipedia lists no less than eight different varieties.

And there are various plausible explanations as to how and why it could have originated. But no one theo…

Kuiper Cliffplugin-autotooltip__plain plugin-autotooltip_bigKuiper Cliff

The Kuiper belt is a concentration of asteroid-like objects in orbit around the Sun, beyond Neptune. Since the belt was discovered in 1992, the number of known Kuiper belt objects (KBOs) has increased to over a thousand. And computed projections indicate t…

Kwashiorkorplugin-autotooltip__plain plugin-autotooltip_bigKwashiorkor

Kwashiorkor is a childhood disease caused by severe malnutrition - which, at the time of its naming in 1935 had a mortality rate of 90%.

It's known to be associated with a lack of protein intake in food. And has also been linked to aflatoxins (fungal toxin…

Kyrle diseaseplugin-autotooltip__plain plugin-autotooltip_bigKyrle disease

Kyrle disease is a relatively rare 'perforating' skin condition which leads to the formation of multiple large (up to 1.5cm) skin papules that have central keratin plugs. It usually affects the legs, but can also erupt in other areas.

Labyrinthitisplugin-autotooltip__plain plugin-autotooltip_bigLabyrinthitis

"Labyrinthitis is an inflammatory disorder of the inner ear, or labyrinth. Clinically, this condition produces disturbances of balance and hearing to varying degrees and may affect one or both ears. Bacteria or viruses can cause acute inflammation of the…

Lamotrigineplugin-autotooltip__plain plugin-autotooltip_bigLamotrigine

Lamotrigine is used as an anticonvulsant and mood stabilizer. Currently prescribed in cases of epilepsy, Lennox–Gastaut syndrome and bipolar disorder. Its active biochemical pathways are not known. more info at Wikipedia

"“The action mechanisms underlying…

Language Acquisitionplugin-autotooltip__plain plugin-autotooltip_bigLanguage Acquisition

"“Language development is thought to proceed by ordinary processes of learning in which children acquire the forms, meanings, and uses of words and utterances from the linguistic input. Children often begin reproducing the words that they are repe…

Language evolutionplugin-autotooltip__plain plugin-autotooltip_bigLanguage evolution

"“Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made…

Laughterplugin-autotooltip__plain plugin-autotooltip_bigLaughter

"“...laughter is more often prompted by banal comments than amusing jokes. That makes it even more mysterious.” Source: New Scientist August 2009."

Laughter, or something very similar, has been observed in various different species – including (but probably…

Leaf fenestrationplugin-autotooltip__plain plugin-autotooltip_bigLeaf fenestration

Several species of plants have leaves which are 'fenestrated' - i.e. have large holes in them (from Latin fenestra, window). Notable examples are the Monstera genus (Araceae) e.g. the Swiss Cheese Plant.

It's known that the holes form due to programm…

Legendre's Conjectureplugin-autotooltip__plain plugin-autotooltip_bigLegendre's Conjecture

Legendre's Conjecture concerns the distribution of Prime Numbers

It states that : there is a prime number between n2 and (n + 1)2 for every positive integer n. squares?“

It was first presented by French mathematician Adrien-Marie Legendre in th…

Levetiracetamplugin-autotooltip__plain plugin-autotooltip_bigLevetiracetam

Levetiracetam, sold under brand names of Keppra, Elepsia, Epictal, Lenerve, Levepsy, Torleva (and many others) is a prescription-only anticonvulsant medication forepilepsy. It is used for partial onset, myoclonic, or tonic-clonic seizures. It is taken b…

Lithium-ion batteriesplugin-autotooltip__plain plugin-autotooltip_bigLithium-ion batteries

"“Although lithium ion batteries are considered as system of choice for variety of mobile and stationary applications, fundamental knowledge is alarmingly required to uncover the underlying principles controlling the basic processes that determin…

Liesegang ringsplugin-autotooltip__plain plugin-autotooltip_bigLiesegang rings

"Liesegang patterning is a special type of chemical pattern formation in which the spatial order is formed by density fluctuations of a weakly soluble salt. From analytical chemistry we know many different reactants that form a precipitate (sparingly s…

Defining Lifeplugin-autotooltip__plain plugin-autotooltip_bigDefining Life

There isn’t, as yet, any definition of a 'lifeform' which can withstand logical scrutiny.

Exceptions can easily be found for any definition so far presented. For example (from The American Heritage Dictionary of the English Language

Life on Earth (timespan)plugin-autotooltip__plain plugin-autotooltip_bigLife on Earth (timespan)

As yet, there is no scientific agreement as to the age of life on Earth. Estimates (based on geological evidence) currently vary by about 200 million years. That's to say between 3.85 billion years ago (Ga), or 3.65 Ga.

To date, the oldest und…

Lightningplugin-autotooltip__plain plugin-autotooltip_bigLightning

High powered lightning discharges are happening somewhere on Earth 100 times every second - as yet there are no agreed explanations as to how or why.

"“One mystery is how thunderclouds become so highly charged. The best explanation is that collisions betwee…

Lignin synthesisplugin-autotooltip__plain plugin-autotooltip_bigLignin synthesis

"Lignin is, after cellulose, the second most abundant terrestrial biopolymer, accounting for approximately 30% of the organic carbon in the biosphere. The ability to synthesize lignin has been essential in the evolutionary adaptation of plants from an…

Limb Regenerationplugin-autotooltip__plain plugin-autotooltip_bigLimb Regeneration

Many animals, notably salamanders, axolotls, starfish &etc are able to regrow limbs which have been lost to accidents or disease. Although mammals can regrow various tissues (notably skin, liver and tail tips) there is no capacity to regrow limbs etc.…

Linear A scriptplugin-autotooltip__plain plugin-autotooltip_bigLinear A script

"Linear A is an undeciphered syllabary used between 1800-1450 BC in ancient Crete, alongside Cretan Hieroglyphs. Linear A was the official script for the palaces and cults, and Cretan Hieroglyphs were used for seals. Cretan Hieroglyphs had been in use …

Lip colourationplugin-autotooltip__plain plugin-autotooltip_bigLip colouration

"The vermilion border of the lips (lip for short) is the only part on the face where the oral mucosa is persistently exposed to the outside. Despite its prominent presence on the face, constituting not only the target of cosmetics but also the site for…

Lithium (treatment for bipolar disorder)plugin-autotooltip__plain plugin-autotooltip_bigLithium (treatment for bipolar disorder)

Lithium, normally in the form of lithium carbonate (Li2CO3) is widely recognised as the 'gold standard' prescribed drug for treating bipolar disorder, depression and mania.

In widespread use since the early 1970s, lithium carb…

Liturgical Combsplugin-autotooltip__plain plugin-autotooltip_bigLiturgical Combs

"A liturgical comb is a decorated comb used ceremonially in both Catholic and Orthodox Christianity during the Middle Ages, and in Byzantine Rite to this day. The exact use of liturgical combs during the Middle Ages remains unclear.

Liubo (ancient Chinese board game)plugin-autotooltip__plain plugin-autotooltip_bigLiubo (ancient Chinese board game)

Liubo 六博 is an ancient Chinese board game for two players.

Historians have determined that it was invented no later than the middle of the 1st millennium BCE - being popular during the Han dynasty (202 BCE – 220 CE).

Lodestoneplugin-autotooltip__plain plugin-autotooltip_bigLodestone

Lodestone is a naturally magnetised form of the mineral Magnetite - which is mostly composed of Iron(II,III)oxide (Fe3O4).

It is of great historical importance in that it led to the discovery and study of magnetism in general, and also made possible the inv…

'Log' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Log' etymology

"Log (n.1) An unshaped large piece of tree, early 14c., of unknown origin. Old Norse had lag “felled tree” (from stem of liggja “to lie,” hence “a tree that lies prostrate”), but many etymologists deny on phonological grounds that this can be the roo…

Lottery ticket swapsplugin-autotooltip__plain plugin-autotooltip_bigLottery ticket swaps

Because the results of (well constructed) lotteries are random, no one ticket is any more likely to win than any other. However, several studies have shown that those who are in possession of a lottery ticket are usually very reluctant to swap it

Lunar Rillesplugin-autotooltip__plain plugin-autotooltip_bigLunar Rilles

Rilles are long, narrow depressions on the surface of the Moon that resemble channels. They can be several kilometers wide and hundreds of kilometers long. The term is also used to describe similar features that have been found on a number of planets in th…

Lupusplugin-autotooltip__plain plugin-autotooltip_bigLupus

"“Systemic lupus erythematosus, also called SLE or lupus, is a disease of the immune system that causes the immune system to attack tissues in various parts of the body. The cause of lupus is unknown. Finding the cause is the object of major research efforts.

Macrophagesplugin-autotooltip__plain plugin-autotooltip_bigMacrophages

Macrophages are a type of white blood cell which are a crucial component of the immune system. They engulf and 'digest' microbes and cancer cells etc. (See Wikipedia)

"Although the overall role of macrophages has been known for over 100 years, we understa…

Macular degenerationplugin-autotooltip__plain plugin-autotooltip_bigMacular degeneration

Macular degeneration, also known as age-related macular degeneration (AMD or ARMD), is a medical condition which results in blurred (or absent) vision in the centre of the visual field.

It's characterised by a gradual and general degeneration of t…

'Mafia' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Mafia' etymology

The origin of the word 'Mafia' , and its derivative(s) 'Mafioso' etc. are disputed.

Etymology-online says :

"The immediate source of mafioso, then, would be 19c. Sicilian mafiusu, “signifying a bully, arrogant but also fearless, enterprising, and p…

Magnesium sulphateplugin-autotooltip__plain plugin-autotooltip_bigMagnesium sulphate

Magnesium sulphate (a.k.a. Epsom Salts, Sedlitz salt, and others) is a simple inorganic compound (MgSO4 - 7H2O) which has been used extensively - from at least the 1600s onwards - to treat a variety of medical conditions such as Asthma,

Magnetic monopolesplugin-autotooltip__plain plugin-autotooltip_bigMagnetic monopoles

A magnetic monopole is a (possibly hypothetical) elementary particle in the form of an isolated magnet with only one magnetic pole (a North pole without a South pole or vice versa). In other words, a particle with a 'magnetic charge' somewhat analog…

Magnetoreceptionplugin-autotooltip__plain plugin-autotooltip_bigMagnetoreception

A number of animal species, including bacteria, arthropods, molluscs, fish, birds and mammals are known to be able to sense magnetic fields.

For some varieties of bacteria, known as Magnetotactic bacteria, the ability is now quite well explained. But …

'Malarkey' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Malarkey' etymology

"“Malarkey (n.) also malarky, “lies and exaggerations, humbug,” 1924, American English, of unknown origin. It also is an Irish surname. Meaning much the same thing at about the same time in U.S. slang was ackamarackus

Source:

Male Pattern Hair Lossplugin-autotooltip__plain plugin-autotooltip_bigMale Pattern Hair Loss

a.k.a. 'Androgenic alopecia' 'Androgenetic alopecia' and 'Alopecia androgenetica'

A variety of genetic (and possibly environmental) factors probably play a role in causing Male Pattern Hair Loss in humans. Many are documented, but there is no ov…

Mammilary bodiesplugin-autotooltip__plain plugin-autotooltip_bigMammilary bodies

The Mammilary Bodies are a pair of small round structures located on the underside of the brain at the end of the Fornix - which is connected to the Hippocampus. ( see diagram at Wikipedia )

They are believed to be associated with memory recall, as da…

Mantle plumesplugin-autotooltip__plain plugin-autotooltip_bigMantle plumes

A Mantle Plume is a proposed convection mechanism of abnormally hot rock within the Earth's mantle. In which huge 'mushroom' shaped plumes of molten rock rise, by thermal convection, towards the surface. From depths of around 3,000Km, and creating volcani…

Marine calcium carbonate balanceplugin-autotooltip__plain plugin-autotooltip_bigMarine calcium carbonate balance

"The chemistry of the oceans has varied significantly over the past several billion years, and it is changing at an unprecedented rate today in response to anthropogenic burning of fossil fuels. [...] Calcium carbonates are among the …

Mars - methaneplugin-autotooltip__plain plugin-autotooltip_bigMars - methane

In 2004, three different research groups independently announced the discovery of significant concentrations of methane in the atmosphere of Mars. But the predicted lifetime of methane in the Martian atmosphere has been calculated at just 200 days (Sourc…

Mars Oceanplugin-autotooltip__plain plugin-autotooltip_bigMars Ocean

Many of the extensively surveyed geological features of Mars suggest that the planet once had an extensive liquid water ocean.

The ex-ocean has been named as Paleo-Ocean and Oceanus Boreali , and some researchers suggest that it could have covered up to 30%…

Massplugin-autotooltip__plain plugin-autotooltip_bigMass

All physical objects have ‘mass’. The mass is (largely) a consequence of the additions of the masses of the atomic and subatomic particles from which the objects are comprised. Theorists currently support the idea of mass-creation via the

Mayan Collapseplugin-autotooltip__plain plugin-autotooltip_bigMayan Collapse

The Maya civilization developed in an area that covered southeastern Mexico, all of Guatemala and Belize, and the western portions of Honduras and El Salvador. It lasted for more than 2000 years, and at its peak there were around 13 major cities, the lar…

Maypolesplugin-autotooltip__plain plugin-autotooltip_bigMaypoles

A maypole is a tall, sometimes highly decorated, wooden pole used in various European folk festivals - around which a 'maypole dance' often takes place.

Historically, maypoles are believed to have originated in Germanic Europe, but are now commonly found in M…

Mild Cognitive Impairment (MCI)plugin-autotooltip__plain plugin-autotooltip_bigMild Cognitive Impairment (MCI)

"Mild cognitive impairment (MCI) is a condition in which individuals demonstrate cognitive impairment with minimal impairment of instrumental activities of daily living (IADL). Source : Neurology. 2018 Jan 16; 90(3): 126–135. "

It can …

ME / CFSplugin-autotooltip__plain plugin-autotooltip_bigME / CFS

"“Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS) is a serious, long-term illness that affects many body systems. People with ME/CFS are often not able to do their usual activities. At times, ME/CFS may confine them to bed. People with ME/CFS ha…

Meditationplugin-autotooltip__plain plugin-autotooltip_bigMeditation

Meditation techniques of one form or another have been used for thousands of years. Practitioners claim a wide range of physical and psychological benefits - many of which have now been verified by controlled scientific studies. Modern scientific techniques,…

Meissner corpusclesplugin-autotooltip__plain plugin-autotooltip_bigMeissner corpuscles

"“The Meissner corpuscle, a mechanosensory end organ, was discovered more than 165 years ago and has since been found in the glabrous skin of all mammals, including that on human fingertips. Although prominently featured in textbooks, the function …

Melanin and UV protectionplugin-autotooltip__plain plugin-autotooltip_bigMelanin and UV protection

In general, people with darker skin tones (i.e. with more melanin) are less likely to suffer from UV-induced skin cancers.

"It has been traditionally believed that skin pigmentation is the most important photoprotective factor, since melanin…

Memoryplugin-autotooltip__plain plugin-autotooltip_bigMemory

On a macro scale, neuroscientists now know (more or less) where memories are 'stored' in the human brain. The brain's hippocampus, the amygdala, the striatum and the mammiliary bodies (for example) are known to be involved in some way, because individuals who s…

Age-related memory declineplugin-autotooltip__plain plugin-autotooltip_bigAge-related memory decline

"Normal aging is associated with a decline in various memory abilities in many cognitive tasks; the phenomenon is known as age-related memory impairment (AMI) or age-associated memory impairment (AAMI). The ability to encode new memories of …

Ménière’s diseaseplugin-autotooltip__plain plugin-autotooltip_bigMénière’s disease

"“Ménière’s disease is a disorder of the inner ear that causes severe dizziness (vertigo), ringing in the ears (tinnitus), hearing loss, and a feeling of fullness or congestion in the ear. Ménière’s disease usually affects only one ear.

Meningiomasplugin-autotooltip__plain plugin-autotooltip_bigMeningiomas

Meningiomas are a category of primary brain tumour. They are slow growing, and often symptom free. They form in the meninges - the thin layer of tissues which surround the brain - rather than in the brain itself.

It's estimated that roughly one in a thousa…

Menopauseplugin-autotooltip__plain plugin-autotooltip_bigMenopause

The decline in the number viable ovarian follicles, which leads to the menopause, is well documented (see Wikipedia), but, from an evolutionary perspective the reasons for its prevalence in humans are unknown.

Only two other mammals are known to exhibit meno…

Menstrual synchronyplugin-autotooltip__plain plugin-autotooltip_bigMenstrual synchrony

Menstrual synchrony (MS) is a proposal that the duration of two or more women’s (or animals’) ovarian cycles shorten or lengthen so as to bring the timing of the onset of their menses into mutual alignment.

The effect was first described in 1971 by…

Mercury - formationplugin-autotooltip__plain plugin-autotooltip_bigMercury - formation

The planet Mercury is the second most dense in the Solar System. Its density is currently calculated at 5.427 g/cm3 ( Earth is 5.514 g/cm3 )

Based on this, the assumption is that Mercury, like Earth, probably has a core composed mainly of (molten)…

The Mesenteryplugin-autotooltip__plain plugin-autotooltip_bigThe Mesentery

"“The mesentery is a continuous set of tissues which is formed by the double fold of peritoneum that attaches the intestines to the wall of the abdomen. ['..] It has been proposed for reclassification as an organ due to research at the University of Lime…

Mesoamerican nephropathyplugin-autotooltip__plain plugin-autotooltip_bigMesoamerican nephropathy

"“An epidemic of chronic kidney disease of unknown origin has emerged in the last decade in Central America and has been named Mesoamerican nephropathy. This form of chronic kidney disease is present primarily in young male agricultural worker…

Metallic catalystsplugin-autotooltip__plain plugin-autotooltip_bigMetallic catalysts

The history of using metallic catalysts to speed up chemical reactions goes back to the mid 1800s. They typically make reaction rates many thousands of times faster.

Without metallic catalysts, many current-day commercial reaction processes would be…

Metforminplugin-autotooltip__plain plugin-autotooltip_bigMetformin

Metformin, sold under the brand names of Bolamyn, Diagemet, Glucient, Glucophage, Metabet, Obimet, Gluformin, Dianben, Diabex, Diaformin, Metsol, Siofor, Metfogamma (and many others) is a prescription-only medication used in the treatment of Type 2 Diabetes. …

Global Atmospheric Methane Cycleplugin-autotooltip__plain plugin-autotooltip_bigGlobal Atmospheric Methane Cycle

Methane is roughly 30 times more potent as a Greenhouse Gas than CO2. Over the last 30 years, the measured levels in the atmosphere have been steadily rising, - maintaining a clearly defined seasonal cycle. 1900 parts per billion (ppb) …

Methane hydratesplugin-autotooltip__plain plugin-autotooltip_bigMethane hydrates

Mehane hydrates - a.k.a. methane clathrates - are an important part of global methane storage (see Global Atmospheric Methane Cycle)

They are commonly found in permafrost deposits and on and under the sea floor, being a frozen, naturally‐occurring, an…

Methocarbamolplugin-autotooltip__plain plugin-autotooltip_bigMethocarbamol

Methocarbamol, sold under the brand names of Robaxin, Robaxin-750, Carbacot, Skelex (and others) is a prescription-only short-term medication used for pain relief in muscle spasms and for musculoskeletal problems.

It was authorised for use in 1957, and t…

M.E.W.D.S.plugin-autotooltip__plain plugin-autotooltip_bigM.E.W.D.S.

Multiple Evanescent White Dot Syndrome (MEWDS) is an eye disorder that was first described by L M Jampol et al. in 1984.

"Patients commonly present with acute unilateral painless decreased vision and photopsias. Presentations like central or paracentral sc…

Micro Black Holesplugin-autotooltip__plain plugin-autotooltip_bigMicro Black Holes

The possible existence of Micro Black Holes (and Mini Black Holes) was first suggested by Stephen Hawking in his 1971 paper 'Gravitationally collapsed objects of very low mass' in the Monthly Notices of the Royal Astronomical Society, Vol. 152, p. 75.…

Microbiome interactionsplugin-autotooltip__plain plugin-autotooltip_bigMicrobiome interactions

"“The human gut harbors trillions of invisible microbial inhabitants, referred to as the microbiota, that collectively produce thousands of unique small molecules. The sources and biological functions of the vast majority of these molecules are…

Microgravity Immune Suppressionplugin-autotooltip__plain plugin-autotooltip_bigMicrogravity Immune Suppression

"“Spaceflight causes alterations in human immunity, a finding which has been well documented immediately following spaceflight. Limited in-flight studies have also confirmed that to some degree immunity is compromised

Microplastics and health implicationsplugin-autotooltip__plain plugin-autotooltip_bigMicroplastics and health implications

Note: Microplastic pollution is so widespread that it's now been found contaminating almost all multicellular lifeforms which have been tested. This article is only related to possible risks to human health.

Nano- and microplastic…

Midlife Crisisplugin-autotooltip__plain plugin-autotooltip_bigMidlife Crisis

A new (2017) research project from the US National Bureau of Economic Research looked at the psychological well-being of 1.3 million randomly sampled people (age 20 to age 90) across 51 countries to determine if anecdotal reports of widespread 'Midlife C…

Migraineplugin-autotooltip__plain plugin-autotooltip_bigMigraine

"“Chronic migraine has a great detrimental influence on a patient’s life, with a severe impact on socioeconomic functioning and quality of life. Chronic migraine affects 1–2% of the general population, and about 8% of patients with migraine; it usually develo…

Millisecond pulsarsplugin-autotooltip__plain plugin-autotooltip_bigMillisecond pulsars

A millisecond pulsar (MSP) is a star (or other entity) which radiates with varying power - oscillating regularly at around 25Hz or more. Some have been found to vary at more than 700Hz. They have been discovered in the radio, X-ray, and gamma ray ra…

Mima moundsplugin-autotooltip__plain plugin-autotooltip_bigMima mounds

Mima Mounds are low, domelike, symmetrical natural mounds - mainly composed of loose, unstratified, often gravelly sediment. They have a diameter of 3 to 50 m, and a height of 0.2 to 2 m.

They are found mainly in the northwestern United States - though si…

The Mind / Body problemplugin-autotooltip__plain plugin-autotooltip_bigThe Mind / Body problem

"Humans have (or seem to have) both physical properties and mental properties. People have (or seem to have) the sort of properties attributed in the physical sciences. These physical properties include size, weight, shape, colour, motion throu…

Minoxidilplugin-autotooltip__plain plugin-autotooltip_bigMinoxidil

Minoxidil (currently sold under the brand names of Rogaine, Loniten, Lonolox, Noxidil, Pilomin, Reten and more than 100 others) is a widely used medication for the treatment of hair loss.

It was originally developed (1950s) as an oral medication for stomach …

Mirror Syndromeplugin-autotooltip__plain plugin-autotooltip_bigMirror Syndrome

Mirror Syndrome is a rare disorder affecting pregnant women and their babies - it was first described in 1892.

"Mirror Syndrome, also known as Ballantyne Syndrome or triple edema. Mirror syndrome happens when the fetus has an abnormal buildup of fluid…

Mirror Therapyplugin-autotooltip__plain plugin-autotooltip_bigMirror Therapy

Mirror therapy is a recently developed technique used to treat chronic Phantom Limb pain. Amputees sometimes feel intense pain in the region of their amputated limb, even though it no longer exists. 80% of patients report having such symptoms at some sta…

Misattributed Artworksplugin-autotooltip__plain plugin-autotooltip_bigMisattributed Artworks

Note: This entry is under consideration in the 'Proposed Content' section

The number of artworks hanging in major galleries worldwide that are 'misattributed' (i.e. fake) is currently unknown.

No formal academic research has yet established an…

Misophoniaplugin-autotooltip__plain plugin-autotooltip_bigMisophonia

"Misophonia is characterized by a negative reaction to a sound with a specific pattern and meaning to a given individual. Individuals with misophonia are sensitive to a specific set of trigger sounds, which are usually recognized since childhood; these soun…

Modafinilplugin-autotooltip__plain plugin-autotooltip_bigModafinil

Modafinil (sold under the brand names Alertec, Alertex, Altasomil, Aspendos, Forcilin, Intensit, Mentix, Modafinil, Modafinilo, Modalert, Modanil, Modasomil, Modvigil, Modiodal, Modiwake, Movigil, Provigil, Resotyl, Stavigile, Vigia, Vigicer, Vigil, Vigimax, …

Molesplugin-autotooltip__plain plugin-autotooltip_bigMoles

Benign moles are extremely common on human skin, but their functions (if any) are unknown. There are theories however - the most prominent being that the extra melanin produced in the moles' melanocytes helps to protect against UV radiation. But melanin-rich site…

Monarch Butterfly migrationplugin-autotooltip__plain plugin-autotooltip_bigMonarch Butterfly migration

"Monarch butterfly migration is the phenomenon, mainly across North America, where the subspecies Danaus plexippus plexippus migrates each summer and autumn to and from overwintering sites on the West Coast of California or mountainous site…

Monogamyplugin-autotooltip__plain plugin-autotooltip_bigMonogamy

As well as humans, many birds, fishes and mammals are broadly monogamous. ( examples here )

Monogamy seems to contradict traditional evolutionary theory, however, because it appears to severely limit the gene-pool available to breeding animals.

There are sev…

The 'Moon Illusion'plugin-autotooltip__plain plugin-autotooltip_bigThe 'Moon Illusion'

"“The Moon illusion is an optical illusion which causes the Moon to appear larger near the horizon than it does higher up in the sky. It has been known since ancient times and recorded by various cultures. The explanation of this illusion is still …

The Moral Superiority Illusionplugin-autotooltip__plain plugin-autotooltip_bigThe Moral Superiority Illusion

"“Most people strongly believe they are just, virtuous, and moral; yet regard the average person as distinctly less so.”"

A comprehensive study from Royal Holloway, University of London, conducted in 2016 concluded that :

Morning Sicknessplugin-autotooltip__plain plugin-autotooltip_bigMorning Sickness

Morning sickness, also called Nausea and Vomiting of pregnancy (NVP) is the most prevalent medical condition associated with pregnancy. Studies put the numbers of pregnant women affected at between 50 and 80 percent. Symptoms are persistent, and range…

Morpheaplugin-autotooltip__plain plugin-autotooltip_bigMorphea

"Morphea (morphoea) is an immune‐mediated disease in which excess synthesis and deposition of collagen in the skin and underlying connective tissues results in hardened cutaneous areas. Morphea has different clinical features according to the subtype and stage…

Moths and light attractionplugin-autotooltip__plain plugin-autotooltip_bigMoths and light attraction

Many insects are quite dramatically attracted to artificial light sources. So called 'Phototaxis'.

Moths in particular are (famously) so drawn to light sources that they frequently get burnt in candle flames.

Moths are known to have a visua…

Motion sicknessplugin-autotooltip__plain plugin-autotooltip_bigMotion sickness

Dizziness and nausea is frequently caused by unusual physical motion (or perceived motion) - e.g. air sickness, sea sickness, car sickness, VR simulation sickness etc etc.

There are three commonly-documented versions :

* Caused by motion that is felt…

Motor Neurone diseaseplugin-autotooltip__plain plugin-autotooltip_bigMotor Neurone disease

Motor Neurone disease, also known as Amyotrophic lateral sclerosis (ALS) and Lou Gehrig's disease, are rare, progressive, neurological conditions that involve degeneration of the nerve cells (neurons) responsible for controlling voluntary muscle m…

Mouth ulcers (RAS)plugin-autotooltip__plain plugin-autotooltip_bigMouth ulcers (RAS)

Some mouth ulcers are caused by physical damage - from the sharp edges of broken fillings etc. The majority, however - collectively known as Recurrent aphthous stomatitis (RAS) have no obvious cause - and so are classed as 'atopic'. Estimates va…

The Moving Sofa problemplugin-autotooltip__plain plugin-autotooltip_bigThe Moving Sofa problem

"“The moving sofa problem is a well-known unsolved problem in geometry, ﬁrst posed by Leo Moser in 1966, It asks: “What is the planar shape of maximal area that can be moved around a right-angled corner in a hallway of unit width?

Mozart's deathplugin-autotooltip__plain plugin-autotooltip_bigMozart's death

The composer Wolfgang Amadeus Mozart died on 5 December 1791 at the age of 35. The circumstances of his death have attracted much research and speculation.

Mozart himself was convinced that he was being poisoned. After a brief period of recovery, howeve…

Mpemba effectplugin-autotooltip__plain plugin-autotooltip_bigMpemba effect

"“Under certain conditions, it takes a shorter time to cool a hot system than to cool the same system initiated at a lower temperature. This phenomenon—the “Mpemba effect”—was first observed in water and has recently been reported in other systems.…

Multiple sclerosisplugin-autotooltip__plain plugin-autotooltip_bigMultiple sclerosis

Multiple sclerosis (MS) is a condition of the central nervous system in which the coating around nerve fibres (myelin) is damaged, causing a range of symptoms varying in severity.

"“The cause of MS is unknown; however, it is believed to occur as a …

Multicellular organismsplugin-autotooltip__plain plugin-autotooltip_bigMulticellular organisms

It's generally assumed that during the evolution of lifeforms, there must have been some stage when single cells (unicelluar organisms) grouped together to form multicellular life.

There are at least nine different major theories regarding how …

Multicopy single-stranded DNAplugin-autotooltip__plain plugin-autotooltip_bigMulticopy single-stranded DNA

Multicopy single-stranded DNA ( msDNA ) is a type of DNA structure found outside the chromosomes in many cells. One of a type of so-called Satellite DNA. It was originally identified in the 1980's, in soil bacteria.

It's now known to be w…

Muon magnetic momentplugin-autotooltip__plain plugin-autotooltip_bigMuon magnetic moment

Recent (2021) analysis of experiments carried out at the US Fermilab accelerator have found that the 'magnetic moment' (magnetic field strength) of the Muon is not in exact agreement with calculations derived from the Standard Model

The experiment…

Muscle memoryplugin-autotooltip__plain plugin-autotooltip_bigMuscle memory

"The performance of many tasks improves, throughout life, with repetition and practice. Even in adulthood simple tasks such as reaching to a target or rapidly and accurately tapping a short sequence of finger movements, which appear, when mastered, to be…

Musical appreciationplugin-autotooltip__plain plugin-autotooltip_bigMusical appreciation

Music psychologists are trying to understand the processes that support musical behaviours - including perception, comprehension, memory, attention, emotional effects, and performance.

Many decades of extensive research has investigated :

Musical pitch perceptionplugin-autotooltip__plain plugin-autotooltip_bigMusical pitch perception

"“Pitch is a perceptual property of sounds that allows their ordering on a frequency-related scale, or more commonly, pitch is the quality that makes it possible to judge sounds as 'higher' and 'lower' in the sense associated with musical melo…

Mustatilsplugin-autotooltip__plain plugin-autotooltip_bigMustatils

Mustatils are ancient (c. 5,300 - 5,000 BC) archeological structures found in large numbers (more than 1,000) across present-day Saudi Arabia and Jordan, in an area of more than 200,000 km².

Their name comes from the Arabic word for 'rectangle', which is the…

Myelomaplugin-autotooltip__plain plugin-autotooltip_bigMyeloma

"“Multiple myeloma, also known as plasma cell myeloma, is a cancer of plasma cells, a type of white blood cell normally responsible for producing antibodies. Often, no symptoms are noticed initially. When advanced, bone pain, bleeding, frequent infections, and…

Non-Alcoholic Fatty Liver Disease - NAFLDplugin-autotooltip__plain plugin-autotooltip_bigNon-Alcoholic Fatty Liver Disease - NAFLD

Non-alcoholic fatty liver disease (NAFLD), also known as metabolic (dysfunction) associated fatty liver disease (MAFLD), is excessive fat build-up in the liver without another clear cause such as alcohol use - with subsequent l…

Naked mole-rat - cancer resistanceplugin-autotooltip__plain plugin-autotooltip_bigNaked mole-rat - cancer resistance

"Naked mole-rats (NMRs; Heterocephalus glaber) are highly adapted, eusocial rodents renowned for their extreme longevity and resistance to cancer. Because cancer has not been formally described in this species, NMRs have been increas…

Naked singularitiesplugin-autotooltip__plain plugin-autotooltip_bigNaked singularities

"In general relativity, a naked singularity is a hypothetical gravitational singularity without an event horizon. In a black hole, the singularity is completely enclosed by a boundary known as the event horizon, inside which the gravitational force…

Narcolepsyplugin-autotooltip__plain plugin-autotooltip_bigNarcolepsy

"“Narcolepsy is a chronic neurological disorder caused by the brain's inability to regulate sleep-wake cycles normally. At various times throughout the day, people with narcolepsy experience irresistable bouts of sleep. If the urge becomes overwhelming, ind…

Narwhal Tusksplugin-autotooltip__plain plugin-autotooltip_bigNarwhal Tusks

"“The narwhal, Monodon monoceros, has long fascinated sea explorers, scientists and aristocracy. This arctic whale is characterized by a single spiraled tusk extending six to nine feet, emerging from the upper jaw and through the lips of adult males. Mal…

Nasal Polypsplugin-autotooltip__plain plugin-autotooltip_bigNasal Polyps

"Nasal polyps (NP) are benign lesions arising from the mucosa of the nasal sinuses (commonly at the outflow tract of one or more of the sinuses) or from the mucosa of the nasal cavity. Source : Therapeutics and Clinical Risk Management. 4(2): 507–512."

N…

Nazca linesplugin-autotooltip__plain plugin-autotooltip_bigNazca lines

The Nazca Lines are an extensive, man-made set of 'geoglyphs' (earth signs) created in the Nazca Desert in southern Peru. The majority are in the form of simple straight lines, but there are also depictions of animals and geometric forms etc.

Non-celiac gluten sensitivity (NCGS)plugin-autotooltip__plain plugin-autotooltip_bigNon-celiac gluten sensitivity (NCGS)

Non-celiac gluten sensitivity (NCGS) is currently defined as : “a clinical entity induced by the ingestion of gluten leading to intestinal and/or extraintestinal symptoms that improve once the gluten-containing foodstuff is removed …

Neanderthal behaviourplugin-autotooltip__plain plugin-autotooltip_bigNeanderthal behaviour

"Almost everything about Neanderthal behaviour remains controversial. Source: Wikipedia"

Despite very extensive research using the fossil record and remains of artefacts, it's still unknown whether the Neanderthal people :

* Used language

Neanderthal extinctionplugin-autotooltip__plain plugin-autotooltip_bigNeanderthal extinction

In August 2014 an international research team reported (in Nature) on a new analysis of 40 sites in Western Europe, concluding that Neanderthals died out about 40,000 years ago.

There are numerous theories which attempt an explanation of their e…

Negative Massplugin-autotooltip__plain plugin-autotooltip_bigNegative Mass

The idea that some exotic forms of matter might have 'negative mass' was first proposed in the 1950's.

In 2017, a team from Washington State University described an set of experiments which claimed observation of negative mass particles.

Neolithic population declineplugin-autotooltip__plain plugin-autotooltip_bigNeolithic population decline

"The Neolithic decline was a rapid collapse in populations between five and six thousand years ago (approximately 3000 BC) during the Neolithic period in western Eurasia. The specific causes of that broad population decline are still debat…

Nettle stingsplugin-autotooltip__plain plugin-autotooltip_bigNettle stings

The mechanical and chemical modes which are used by nettles to 'sting' have been studied for more than 150 years.

"“The toxic effects of extracts from stinging hairs of Urtica spp. have not been well characterized due to the difficulty in extracting tox…

Neural Networksplugin-autotooltip__plain plugin-autotooltip_bigNeural Networks

"“Multilayer neural networks are among the most powerful models in machine learning, yet the fundamental reasons for this success defy mathematical understanding.” Source: Proceedings of the National Academy of Sciences 2018"

'Artificial Intelligen…

Neural regenerationplugin-autotooltip__plain plugin-autotooltip_bigNeural regeneration

It's known that neural tissue can routinely re-generate in several species. The subject is intensely researched because of its potential to re-grow neural tissue which has been damaged, either due to disease (e.g. Parkinson's disease and Multiple sc…

Neurofibrillary tanglesplugin-autotooltip__plain plugin-autotooltip_bigNeurofibrillary tangles

Neurofibrillary tangles (which are technically described as 'aggregates of hyperphosphorylated tau protein') are commonly known as a primary marker of Alzheimer's disease. Their presence is also found in numerous other diseases - generally know…

Neuromelaninplugin-autotooltip__plain plugin-autotooltip_bigNeuromelanin

"“Neuromelanin (NM) is a dark insoluble polymer pigment produced in specific populations of catecholaminergic neurons in the brain. Humans have the largest amount of NM, which is present in lesser amounts in other primates, and totally absent in many othe…

Neuropathic painplugin-autotooltip__plain plugin-autotooltip_bigNeuropathic pain

Neuropathic pain is caused by damage or disease in the nervous system. It's estimated that more than 5% of the global population is affected, often severely.

"Central neuropathic pain is found in spinal cord injury, multiple sclerosis, and some strok…

Neuropoiesisplugin-autotooltip__plain plugin-autotooltip_bigNeuropoiesis

Neuropoeisis is the process by which neural stem cells differentiate and grow into various types of adult neuronal cells.

Until the 1960s it was assumed that adult humans could not grow new nerve cells - this viewpoint is now proved to be untrue.

Neutral atomic nucleiplugin-autotooltip__plain plugin-autotooltip_bigNeutral atomic nuclei

"The existence of neutral nuclei has been a long-standing question in nuclear physics. Over the last forty years very different techniques have been employed in various laboratories for the search of multineutrons, mainly 3,4n, without success. A…

Neutrino massplugin-autotooltip__plain plugin-autotooltip_bigNeutrino mass

New research has found that the neutrino has a non-zero mass - but this requires a modification to the Standard Model of particle physics. The non-zero mass also means that neutrinos cannot travel at light-speed as photons do.

"“Although neutrinos were …

Neutron CP problemplugin-autotooltip__plain plugin-autotooltip_bigNeutron CP problem

The neutron CP problem is a disparity between the Standard Model view of particle physics, and theoretical aspects of QCD (Quantum Chromo Dynamics).

The neutron (as the name implies) has a neutral electrical 'charge', because the three quarks from …

Neutron decayplugin-autotooltip__plain plugin-autotooltip_bigNeutron decay

When part of an atomic nucleus, neutrons are extremely stable, but 'free' neutrons (i.e. those outside of a nucleus) decay into a proton, an electron and an electron-antineutrino in about 15 minutes.

Two different methods have been used to measure the ne…

Nicolau Syndromeplugin-autotooltip__plain plugin-autotooltip_bigNicolau Syndrome

Nicolau Syndrome (also known as Livedo-like dermatitis, Livedoid dermatitis and Embolia cutis medicamentosa) is an uncommon complication of intramuscular injections, leading to variable degrees of tissue necrosis including the skin and deeper tissues…

Nitrifying bacteriaplugin-autotooltip__plain plugin-autotooltip_bigNitrifying bacteria

"The enzymatic reactions that occur during nitrification are nature’s means to use ammonia as cellular fuel. Complete understanding of nitrification and related processes are vital to sustainable agriculture and renewable energy technologies.

Novikov conjectureplugin-autotooltip__plain plugin-autotooltip_bigNovikov conjecture

"“The Novikov conjecture attempts to answer the following question: Which expressions of the rational Pontryagin characteristic classes are homotopy invariant for the closed manifolds and how should we classify them.”

Source

The Nuclear Matrixplugin-autotooltip__plain plugin-autotooltip_bigThe Nuclear Matrix

"“When cell nuclei (or cells) are extracted in certain ways, an extensive array of filaments is observed in the remnant nucleus: “the nuclear matrix.” Onto this framework virtually every step in gene readout has been conceptually draped. Some invest…

Nuclear movement in plantsplugin-autotooltip__plain plugin-autotooltip_bigNuclear movement in plants

It's been known for many decades that the nuclei of animal cells are constantly in motion within the cell. Less well know, and less well studied, is the fact that the nuclei of plant cells are also often in constant motion.

Number of speciesplugin-autotooltip__plain plugin-autotooltip_bigNumber of species

"“We demonstrate that after more than six decades, estimates of global species richness have failed to converge, remain highly uncertain, and in many cases, are logically inconsistent.” Source: BROKEN-LINK:Global species richness estimates have n…

Numerical cognitionplugin-autotooltip__plain plugin-autotooltip_bigNumerical cognition

Many animals have demonstrated abilities to count numbers - a.k.a Numerical Cognition. This fits in with evolutionary theory in the sense that it could be advantageous for an animal to understand (small) numbers when involved in feeding, threat sit…

Nuraghesplugin-autotooltip__plain plugin-autotooltip_bigNuraghes

Nuraghes are ancient stone-built structures found in modern-day Sardinia. They are generally considered to be the best-preserved and largest Bronze Age remains in Europe.

It's estimated that they were built between 1900 and 730 B.C.. The remains of more than …

Foliar nictinastyplugin-autotooltip__plain plugin-autotooltip_bigFoliar nictinasty

Foliar Nictinasty (FN) is the tendency for (some) plants to open their leaves during daylight hours and close them at night - tightly following the day/night cycle.

This process has been observed and debated for at least 2,000 years. In 1729

Obsessive-Compulsive disorderplugin-autotooltip__plain plugin-autotooltip_bigObsessive-Compulsive disorder

Obsessive–compulsive disorder (OCD) is a mental disorder in which a person feels the need to perform certain routines repeatedly (called “compulsions”), or has certain thoughts repeatedly (called “obsessions”). The person is unable to cont…

Oceanic CO2 absorptionplugin-autotooltip__plain plugin-autotooltip_bigOceanic CO2 absorption

Estimates for the amount of man-made CO2 absorbed by the oceans is estimated at around 30 > 40%. The processes which govern the rate of absorption are extremely complex and poorly understood.

Examples:

• As the ocean warms, its capacity to abso…

Octopus camouflageplugin-autotooltip__plain plugin-autotooltip_bigOctopus camouflage

Many species of octopuses (and some other cephalopods) have extremely efficient mechanisms for camouflaging themselves against coloured backgrounds. They also use coloured patterns for communication and for repelling predators. The physical mechanism…

Odd 'Perfect Numbers'plugin-autotooltip__plain plugin-autotooltip_bigOdd 'Perfect Numbers'

So called 'Perfect Numbers' have been studied and described since (at least) 300BC. They are numbers where the divisors, added together, equal the example number. e.g.

6 = 1 + 2 + 3

28 = 1 + 2 + 4 + 7 + 14

496 = 1 + 2 + 4 + 8 + 16 + 31 + 62 + 1…

Origins of Oil, Gas, and Coalplugin-autotooltip__plain plugin-autotooltip_bigOrigins of Oil, Gas, and Coal

"“[...] it is now generally accepted, but not conclusively proven, that petroleum formation predominantly arises from the decay of organic matter in the earth. [...] alternative theories should not be dismissed until it can be conclusivel…

The Olmec Civilisationplugin-autotooltip__plain plugin-autotooltip_bigThe Olmec Civilisation

The civilisation now known as The Olmecs are believed to be the first Mesoamerican civilization, living in the region that is now Mexican states of Veracruz and Tabasco. The Olmecs are generally considered as the forerunner of all subsequent Meso…

'On Water' reactionsplugin-autotooltip__plain plugin-autotooltip_big'On Water' reactions

On water reactions are a group of organic reactions that take place as an emulsion in water and that exhibit an unusual reaction rate acceleration compared to the same reaction in an organic solvent, or compared to the corresponding dry media react…

Oncogenesplugin-autotooltip__plain plugin-autotooltip_bigOncogenes

Several hundred oncogenes - genes which which have to potential to increase the risk of cancer - have now been identified. The way(s) in which they do so is as yet unknown.

"“A fundamental aim of cancer research is to identify the molecular changes that cau…

Oppermann's conjectureplugin-autotooltip__plain plugin-autotooltip_bigOppermann's conjecture

Oppermann's Conjecture concerns the distribution of Prime Numbers.

It was first suggested in 1877, and has not been proved or disproved since then.

The conjecture states that : for every integer x > 1, there is at least one prime number between

Orchid dormancyplugin-autotooltip__plain plugin-autotooltip_bigOrchid dormancy

Orchids often enter periods of dormancy - when the plant goes into what some call a 'rest' period, and shows no signs of growth (either above or below ground). The triggers which cause the plants to enter and emerge from the dormant state are as yet unk…

Researchers using the Australian Square Kilometre Pathﬁnder telescope - a wide bandwidth radio telescope based 800 km north of Perth, in the Murchison region of Western Australia - have announced (June 2020) the discovery of what they are calling “O…

Organogelsplugin-autotooltip__plain plugin-autotooltip_bigOrganogels

An Organogel is a class of semi-solid chemical gel formed from a liquid organic phase within a three-dimensional, cross-linked network.

The gels form either through polymerisation, or by so-called 'self assembly' (believed to be a combination of Van der Wal…

Ormeloxifeneplugin-autotooltip__plain plugin-autotooltip_bigOrmeloxifene

Ormeloxifene (sold under the trade names of Shaleli, Choice-7, Novex-DS, Centchroman and Centron) is one of the Selective Estrogen Receptor Modulators, or SERMs, a class of medication which acts on the human estrogen receptor.

It's best known as a non-ste…

Orthostatic hypertensionplugin-autotooltip__plain plugin-autotooltip_bigOrthostatic hypertension

"Orthostatic hypertension—a rise in blood pressure upon assuming upright posture—is an underappreciated and understudied clinical phenomenon. There is currently no widely agreed-upon definition of clinical orthostatic hypertension, the current…

Osteoarthritisplugin-autotooltip__plain plugin-autotooltip_bigOsteoarthritis

"Osteoarthritis (OA) is considered a complex multifactorial disease of weight-bearing joints, with extensive psychosocial impact. The etiology of primary OA remains unknown and the molecular and cellular mechanisms of OA initiation and progression are n…

Osteochondromasplugin-autotooltip__plain plugin-autotooltip_bigOsteochondromas

"Osteochondromas are the most common benign tumors of the bones.The tumors take the form of cartilage-capped bony projections or outgrowth on the surface of bones exostoses. It is characterized as a type of overgrowth that can occur in any bone where c…

Outfielder problemplugin-autotooltip__plain plugin-autotooltip_bigOutfielder problem

"“How does a baseball outfielder know where to run to catch a fly ball? The “outfielder problem” remains unresolved, and its solution would provide a window into the visual control of action. It may seem obvious that human action is based on an inte…

The Ouzo Effectplugin-autotooltip__plain plugin-autotooltip_bigThe Ouzo Effect

The Ouzo Effect is the name given to the spontaneous rapid formation of an emulsion - micro and nano-scale oily droplets suspended in water - when (as an example) the alcoholic drink Ouzo is added to water (or vice versa).

'Normal' emulsions require t…

Ovarian agingplugin-autotooltip__plain plugin-autotooltip_bigOvarian aging

As women age, they experience a decline in reproductive performance leading to menopause (average 51 ± 8 years). This decline is tied to a reduction in the number of ovarian follicles present in the ovaries. The events that lead to to the decline - i.e. …

Overtraining syndromeplugin-autotooltip__plain plugin-autotooltip_bigOvertraining syndrome

"“When prolonged, excessive training stresses are applied concurrent with inadequate recovery, performance decrements and chronic maladaptations occur. Known as the overtraining syndrome (OTS), this complex condition afflicts a large percentage o…

The Oxygen Effect (radiology)plugin-autotooltip__plain plugin-autotooltip_bigThe Oxygen Effect (radiology)

The Oxygen Effect refers to the discovery (made in 1921) that living cells are significantly more damaged by radiation (X-ray, particle beams etc) in the presence of oxygen.

It's currently of particular significance to radiologists, who w…

Oxygen Evolving Process (EVP)plugin-autotooltip__plain plugin-autotooltip_bigOxygen Evolving Process (EVP)

"Photosynthetic oxygen evolution is the fundamental process by which oxygen is generated in earth's biosphere. The reaction is part of the light-dependent reactions of photosynthesis in cyanobacteria and the chloroplasts of green algae an…

Oxyphil cellsplugin-autotooltip__plain plugin-autotooltip_bigOxyphil cells

Oxyphil cells are a specialised group of cells found in the ParaThyroid gland of humans (and some other mammals).

They're not present at birth, and their numbers increase with age. They also increase in patients with chronic kidney disease.

Ozone Depletion Eventsplugin-autotooltip__plain plugin-autotooltip_bigOzone Depletion Events

The Earth's Troposphere regularly experiences (naturally occurring *) ozone depletion events. (Note that the presence of atmospheric ozone is of extreme importance to organic life, as it substantially 'filters' UV radiation from the Sun reaching …

Ozone depletion anomalyplugin-autotooltip__plain plugin-autotooltip_bigOzone depletion anomaly

According to a 2007 research project, the current atmospheric theories regarding depletion of the Earth's ozone 'layer' at the poles only account for around 40% of the actual depletion as measured by NASA. See: Is a major fraction of polar ozon…

Autoimmune pancreatitisplugin-autotooltip__plain plugin-autotooltip_bigAutoimmune pancreatitis

Autoimmune pancreatitis is an inflammatory disease that produces pancreatic masses and ductal problems which can be mistaken for pancreatic cancer in x-ray and CAT scans. The initial symptoms (jaundice and nausea etc) of the disease are also sim…

Paracetamolplugin-autotooltip__plain plugin-autotooltip_bigParacetamol

One of the most widely prescribed drugs in history works by mechanisms which have not yet been agreed upon by the medical establishment. It‘s believed that paracetamol acts via more than one neurological pathway, one of which may be by inhibiting the COX-3 …

Paraspeckles (cell component)plugin-autotooltip__plain plugin-autotooltip_bigParaspeckles (cell component)

"In cell biology, a Paraspeckle is an irregularly shaped compartment of the cell, approximately 0.2-1 μm in size, found in the nucleus' interchromatin space See Wikipedia"

Paraspeckles were first discovered (1990's) in human cancer cells…

Parkinson's diseaseplugin-autotooltip__plain plugin-autotooltip_bigParkinson's disease

Also known as Parkinson disease, Parkinson's, idiopathic parkinsonism, primary parkinsonism, PD, or paralysis agitans - is a degenerative disorder of the central nervous system resulting from the death of dopamine-containing cells in the

Parsonage-Turner Syndromeplugin-autotooltip__plain plugin-autotooltip_bigParsonage-Turner Syndrome

The brachial plexus is a network of nerves that conducts signals from the spine to the shoulder, arm, and hand.

Parsonage-Turner Syndrome, or brachial plexitis, causes inflammation of the brachial plexus without any obvious shoulder injury. T…

Paternal age hypothesisplugin-autotooltip__plain plugin-autotooltip_bigPaternal age hypothesis

The idea that the age of fathers (i.e. the father's age at conception of their children) might affect the ongoing physical and psychological health of their children goes back to 1912.

Various effects have been studied, including the probabilit…

Pearl formationplugin-autotooltip__plain plugin-autotooltip_bigPearl formation

Pearls are the only 'gems' produced by a living organism. Their formation process (either by natural means or through human intervention) is a response to an injury in an oyster's 'mantle' tissue, such as an intrusion by a foreign body, e.g. a sand grai…

'Penguin' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Penguin' etymology

The origin of the English word 'Penguin' is obscure.

It's been suggested that it may have come from the Welsh words pen - meaning 'head' - and gwyn - meaning 'white'.

Though, notably, many penguins don't have white heads, and are scarce in Wales.

Perfect Cuboidsplugin-autotooltip__plain plugin-autotooltip_bigPerfect Cuboids

A 'Perfect Cuboid' (also called a Perfect Euler Brick) is a (proposed) cuboid whose space diagonal also has integer length. That's to say a2 + b2 + c2 = g2 (where a, b, c are the sides and g is the diagonal).

There is currently no mathematical proof t…

Perforated batonsplugin-autotooltip__plain plugin-autotooltip_bigPerforated batons

“Perforated” or “Pierced Batons” (in French “bâton percé”) are man-made historical artefacts formed from deer antlers. They have been found widely distributed across Europe, and range in age from around 23K to 12K years old. They are typically 'Y' or …

Perniosisplugin-autotooltip__plain plugin-autotooltip_bigPerniosis

Perniosis (a.k.a. Chilblains) is a seasonal condition triggered by prolonged exposure to cold and humidity. It typically affects the toes ( though also the lower legs, hands, ears and face ) where inflammation of the small blood vessels lead to painful, itch…

Persistent luminescenceplugin-autotooltip__plain plugin-autotooltip_bigPersistent luminescence

Persistent luminescence is the name given to the phenomenon found in materials which glow in the dark after the end of an excitation with UV or visible light - mainly phosphors such as silver-activated zinc sulphide or doped strontium aluminate…

Personhoodplugin-autotooltip__plain plugin-autotooltip_bigPersonhood

"“Personhood continues to be a topic of international debate and has been questioned critically during the abolition of human and nonhuman slavery, in debates about abortion and in fetal rights and/or reproductive rights, in animal rights activism, in theol…

PES (pseudoexfoliation syndrome)plugin-autotooltip__plain plugin-autotooltip_bigPES (pseudoexfoliation syndrome)

PES or PEX (pseudoexfoliation glaucoma) is an age-related disease which features accumulations of microscopic granular amyloid-like protein fibers in various parts of the body, especially the eyes. It can lead to poor vision, glaucoma a…

'Pet' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Pet' etymology

"“domesticated or tamed animal kept as a favorite,” 1530s, originally in Scottish and northern England dialect (and exclusively so until mid-18c.), a word of unknown origin. Sense of “indulged or favorite child” (c. 1500) is recorded slightly earlier t…

PFAPAplugin-autotooltip__plain plugin-autotooltip_bigPFAPA

"“Periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome is a medical condition, typically starting in young children, in which high fever occurs periodically at intervals of about 3–5 weeks, frequently accompanied by aphthous-like ulcers, pharyn…

PFAS pollutionplugin-autotooltip__plain plugin-autotooltip_bigPFAS pollution

Perfluoroalkyl and polyfluoroalkyl substances ( PFAS ) are synthetic organofluorine chemical compounds which have multiple fluorine atoms attached to an alkyl chain. They have been commercially produced in vast quantities since the 1940s, and have applic…

Photic Sneezingplugin-autotooltip__plain plugin-autotooltip_bigPhotic Sneezing

"“The photic sneeze reflex is a reflex condition that causes sneezing in response to numerous stimuli, such as looking at bright lights or periocular (surrounding the eyeball) injection. The condition affects 18–35% of the world's population

Photodarkeningplugin-autotooltip__plain plugin-autotooltip_bigPhotodarkening

"“Photodarkening is the effect that the optical losses in a medium can grow when the medium is irradiated with light at certain wavelengths.”"

It's of particular significance in systems which use lasers to transmit information along optical fibres. The…

Photoisomerizationplugin-autotooltip__plain plugin-autotooltip_bigPhotoisomerization

Photo-isomerization is the name given to the structural re-arrangement of asymmetric chemical compound molecules from one 'isomer' (e.g. 'left-handed' or 'right handed') to another when illuminated.

The process is normally reversible, is dependent o…

Photonic magnetisationplugin-autotooltip__plain plugin-autotooltip_bigPhotonic magnetisation

The idea that it may be possible to change the magnetic polarisation of a material solely by the use of circularly-polarised photon pulses (rather than by applying a magnetic field) was first suggested in 2006.

The paper All-Optical Magnetic Re…

Photosynthesisplugin-autotooltip__plain plugin-autotooltip_bigPhotosynthesis

"“Photosynthetic water splitting (or oxygen evolution) is one of the most important reactions on the planet, since it is the source of nearly all the atmosphere's oxygen [...] The mechanism of water oxidation is still not fully elucidated,

Pi normalityplugin-autotooltip__plain plugin-autotooltip_bigPi normality

A 'normal' sequence of numbers is one in which no digit occurs more frequently than any other. The mathematical equivalent of White Noise.

'Normality' is usually considered to be one of the tests for randomness.

The Pi sequence has now been computed to

Picaplugin-autotooltip__plain plugin-autotooltip_bigPica

Pica is a condition involving persistent eating of 'nonfood' substances (aside from reasons of cultural or social practice) for at least 1 month.

Some variations of pica, such as the eating of rocks or earth etc., can be linked to deficiencies of minerals etc. - …

Homing pigeons can very reliably find their way back to their adopted roosting place - even when they have been physically removed hundreds of kilometres - (and often without any knowledge of the route).

It's known that they use a variety of methods …

Pingueculaplugin-autotooltip__plain plugin-autotooltip_bigPinguecula

Pinguecula refers to benign degenerative conjunctival lesions, usually found on the nasal side of each eye.

Published figures of prevalence range from 11 - 75% (prevalence depends on age and geographical location). Most people over 70 show some signs.

Pit Alignmentsplugin-autotooltip__plain plugin-autotooltip_bigPit Alignments

"“Pit alignments are a little-known type of prehistoric monument found throughout the British Isles, the function of which is at present poorly understood. They consist of a series of evenly spaced and often relatively shallow pits arranged in lines. Th…

Placebo effectplugin-autotooltip__plain plugin-autotooltip_bigPlacebo effect

Placebos are faux medications - typically lactose or microcrystalline cellulose - designed to act as inert, non-functional 'controls' in medical experiments. (There are also faux medical procedures, see section below)

From the beginnings of their use i…

Planet formationplugin-autotooltip__plain plugin-autotooltip_bigPlanet formation

"“The origin of planets is a vast, complex, and still quite mysterious subject. Despite decades of space exploration, ground-based observations, and detailed analyses of meteorites and cometary grains (the only space samples available in our laborator…

Planetary Nebulae structureplugin-autotooltip__plain plugin-autotooltip_bigPlanetary Nebulae structure

A planetary nebula is a type of 'emission nebula' consisting of an expanding, glowing shell of ionized gas which was ejected from 'red giant' stars at a late stage in their development.

About 20% of the nebulae are roughly spherical (as mig…

Polymorphous light eruption (PLE)plugin-autotooltip__plain plugin-autotooltip_bigPolymorphous light eruption (PLE)

Polymorphous Light Eruption (PLE or PMLE) is a skin condition triggered by exposure to sunlight (or artificial UV light).

It was first described in 1942, and results in an irritable itchy rash which appears several hours (sometimes da…

'Plot' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Plot' etymology

"The word plot has no known origin and exists solely in English. The noun dates from the late 10th or early 11th century and originally meant “a small piece of land or area of ground.” Plot in the sense “a small piece of land in a cemetery” was origin…

Medically induced coma neuropathyplugin-autotooltip__plain plugin-autotooltip_bigMedically induced coma neuropathy

Medically induced comas are routinely used in many Intensive Care Units for patients with severe brain injuries, seizures, and when mechanical ventilation is needed (e.g. in COVID19 patients).

Patients who have been placed in prolonge…

Psychogenic Non-Epileptic seizure (PNES)plugin-autotooltip__plain plugin-autotooltip_bigPsychogenic Non-Epileptic seizure (PNES)

Psychogenic non-epileptic seizures are seizure events which appear similar to those of Epilepsy, but without the associated (easily identifiable) electrical brainwave patterns.

The seizures can be severe, and last up to two min…

Postoperative cognitive dysfunction - POCDplugin-autotooltip__plain plugin-autotooltip_bigPostoperative cognitive dysfunction - POCD

"“Postoperative cognitive dysfunction (POCD) is a decline in cognitive function (especially in memory and executive functions) that may last from 1–12 months after surgery, or longer. In some cases, this disorder may persist…

Poliomyelitisplugin-autotooltip__plain plugin-autotooltip_bigPoliomyelitis

"“Nearly 100 years after its discovery poliovirus remains one of most thoroughly studied and best understood virus models for the molecular virologist. While poliovirus has been of vital importance for our insight into picornavirus biology at the cellula…

Pollen Tubesplugin-autotooltip__plain plugin-autotooltip_bigPollen Tubes

"A pollen tube is a tubular structure produced by the male gametophyte of seed plants when it germinates. Pollen tube elongation is an integral stage in the plant life cycle. The pollen tube acts as a conduit to transport the male gamete cells from the po…

Pollinator constancyplugin-autotooltip__plain plugin-autotooltip_bigPollinator constancy

'Pollination syndromes' is the name given to the various ways in which flowering plants have evolved 'strategies' to disperse their pollen - e.g. by insects, wind, etc.

With regard to insect pollination, it was noted as far back as the time of Ari…

Polycystic ovary syndromeplugin-autotooltip__plain plugin-autotooltip_bigPolycystic ovary syndrome

"Polycystic ovaries contain a large number of harmless follicles that are up to 8mm (approximately 0.3in) in size. The follicles are underdeveloped sacs in which eggs develop. In PCOS, these sacs are often unable to release an egg, which mean…

Polypeptide antibioticsplugin-autotooltip__plain plugin-autotooltip_bigPolypeptide antibiotics

"Polypeptide antibiotics are a chemically diverse class of anti-infective and antitumor antibiotics containing non-protein polypeptide chains. Examples of this class include actinomycin, bacitracin, colistin, and polymyxin B.

Positron excessplugin-autotooltip__plain plugin-autotooltip_bigPositron excess

A 'Positron Excess' in cosmic emissions from deep space have recently been logged by various observation satellites ( PAMELA, Fermi-LAT and AMS-02 ).

As yet, there is no agreed explanation for the source of the positrons (i.e. 'anti' electrons ) in the…

Postpartum depressionplugin-autotooltip__plain plugin-autotooltip_bigPostpartum depression

"Postpartum depression (PPD), also called postnatal depression, is a type of mood disorder associated with childbirth, which can affect both sexes. Symptoms may include extreme sadness, low energy, anxiety, crying episodes, irritability, and chan…

Post-polio syndromeplugin-autotooltip__plain plugin-autotooltip_bigPost-polio syndrome

"Post-polio syndrome (PPS, poliomyelitis sequelae) is a group of latent symptoms of poliomyelitis (polio), occurring at about a 25 to 40% rate (latest data greater than 80%). It is a viral infection of the nervous system after the initial infection…

'Prawn' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Prawn' etymology

"prawn (n.) “long-tailed, ten-footed shrimp-like crustacean, abundant on the shores of the British Isles,” early 15c., prayne, a word of unknown origin. “No similar name found in other langs.” [OED]. Source : Etymology Online"

Note: The

Pre-eclampsiaplugin-autotooltip__plain plugin-autotooltip_bigPre-eclampsia

"Pre-eclampsia is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine. When it arises, the condition begins after 20 weeks of pregnancy. In severe cases of the disease there may…

Prime Numbersplugin-autotooltip__plain plugin-autotooltip_bigPrime Numbers

Since all other whole numbers (except 0) can be produced by multiplying together primes – they must be considered fundamental.

(1), 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 &etc

Although billions of them have so far been found (nowadays via computational …

Primidoneplugin-autotooltip__plain plugin-autotooltip_bigPrimidone

Primidone (a.k.a. Mysoline, Lepsiral, Mysoline, Resimatil and others) is a commonly prescribed anticonvulsant (barbiturate) drug used to treat Epilepsy, Essential Tremorand other disorders. It has more than 2 million yearly prescriptions in the US alone.

It …

Primordial Soupplugin-autotooltip__plain plugin-autotooltip_bigPrimordial Soup

"“In 1953 an iconic set of experiments showed that some of the chemical building blocks of life, such as amino acids, could form spontaneously in the atmospheric conditions thought to prevail on the primordial Earth. This gave rise to the idea that the…

Prion replicationplugin-autotooltip__plain plugin-autotooltip_bigPrion replication

"“Prions are infectious agents composed entirely of a protein material that can fold in multiple, structurally distinct ways, at least one of which is transmissible to other prion proteins, leading to disease in a manner that is epidemiologically com…

Protein Knottingplugin-autotooltip__plain plugin-autotooltip_bigProtein Knotting

"“Knotting in proteins was once considered exceedingly rare. However, systematic analyses of solved protein structures over the last two decades have demonstrated the existence of man…

Protein structuringplugin-autotooltip__plain plugin-autotooltip_bigProtein structuring

Genes set the order that amino acids (the chemical building blocks of proteins) appear in the proteins which they code for. But, working from the gene, the form which the protein's 3-D structure will take cannot as yet be predicted. The extremely co…

Proton Hoppingplugin-autotooltip__plain plugin-autotooltip_bigProton Hopping

Proton hopping - a.k.a. the Grotthuss Mechanism has been said to be “the fastest known chemical reaction”. The effects of which were first noted by Theodor Grotthuss in 1805, who was investigating the decomposition of water under electrolysis.

In the pr…

Proton Mass Calculationsplugin-autotooltip__plain plugin-autotooltip_bigProton Mass Calculations

The mass of a proton has only been calculated to an accuracy of around 4% - (roughly 938 MeV/c2 or 1.672 × 10-27 kg). The constituent particles - quarks and gluons - which make up the proton have individual masses that add up to only around 1% …

Until 2010, measurements (backed up by theory) had put the radius of the proton at about 0.87 femtometres, but in that year, experiments at the Max Planck Institute of Quantum Optics in Germany found a 4% discrepancy.

And in 2016, new experiments …

The Proton Spin Crisisplugin-autotooltip__plain plugin-autotooltip_bigThe Proton Spin Crisis

'Spin' is an intrinsic property of many subatomic particles - it's been likened in some ways to the 'angular momentum' of a spinning ball, - but more accurately is a mathematical 'vector' or 'property'.

After the discovery that protons are compo…

Psoriasisplugin-autotooltip__plain plugin-autotooltip_bigPsoriasis

"“Psoriasis is a long-lasting autoimmune disease characterized by patches of abnormal skin. These skin patches are typically red, dry, itchy, and scaly. On people with darker skin the patches may be purple in colour. Psoriasis varies in severity from small, …

Psoriatic Arthritisplugin-autotooltip__plain plugin-autotooltip_bigPsoriatic Arthritis

"Psoriatic arthritis, in short called PsA, is a rheumatologic disease that effects about 1,5 million Americans. About one in three people with the skin disease psoriasis, will get psoriatic arthritis. It affects the joints as well as the tendons, a…

Psychedelic drugsplugin-autotooltip__plain plugin-autotooltip_bigPsychedelic drugs

Psychedelic drugs have a somewhat circular definition. Classed as hallucinogenic psychoactive drugs which have the primary effect of triggering non-ordinary states of consciousness - termed 'psychedelic' experiences.

Many of the known psychedelic s…

Psychobioticsplugin-autotooltip__plain plugin-autotooltip_bigPsychobiotics

It's been known for many years that the microbiome (the bacterial and viral components of gut contents) can affect the physical wellbeing of mammals, including humans.

It's recently been suggested that the micro-organisms might also be able to affect hum…

Psychogenic painplugin-autotooltip__plain plugin-autotooltip_bigPsychogenic pain

Psychogenic pain, a.k.a. persistent somatoform pain disorder and functional pain syndrome has been defined as physical pain that is caused, increased, or prolonged by mental, emotional, or behavioral factors.

It may be linked to stress, unexpressed e…

Psychosomatic prevalenceplugin-autotooltip__plain plugin-autotooltip_bigPsychosomatic prevalence

Note: This item is currently under review in the 'proposed content' section

A 1999 Russian study put the number of patients in hospital with Psychosomatic disorders (i.e. illness without physical cause ) at over 50%

See: Psychosomatic disord…

Post-traumatic stress disorder (PTSD)plugin-autotooltip__plain plugin-autotooltip_bigPost-traumatic stress disorder (PTSD)

"“PTSD is a medical diagnosis, established in 1980, defining symptoms that last at least a month after experiencing a major trauma. These symptoms include remembering or reliving the trauma when you do not choose to; feeling numb …

Pubic Hairplugin-autotooltip__plain plugin-autotooltip_bigPubic Hair

"“It has long been assumed that pubic hair is a remnant of a furrier period in our evolutionary history, and that the real question is why the rest of the body lost its hirsuteness.” Source: New Scientist August 2009."

Many theories have been proposed to e…

Pumapunkuplugin-autotooltip__plain plugin-autotooltip_bigPumapunku

Pumapunku or Puma Punku (from the Aymara and Quechua words puma, meaning cougar or puma, and punku door) is part of a large Inca temple complex or monument group at the Tiwanaku Site near Tiwanaku, in western Bolivia. It's noted for its exceptional and precis…

The Pyramids - constructionplugin-autotooltip__plain plugin-autotooltip_bigThe Pyramids - construction

Construction engineers and archaeologists have not been able to agree on ways in which the Great Pyramids of Giza (and others) might have been constructed - at around 2580–2560 BC.

"“The logistics involved in the construction of this pyram…

Quantum mechanicsplugin-autotooltip__plain plugin-autotooltip_bigQuantum mechanics

This is a general note about the yet-to-be-understood complexities of quantum theory

Here are some 20th century quotes from eminent scientists regarding its extreme counter-intuitiveness :

"• “Those who are not shocked when they first come across q…

Quarksplugin-autotooltip__plain plugin-autotooltip_bigQuarks

Following theoretical calculations, particle accelerator experiments in the 1970s confirmed that quarks are responsible for forming the nuclear particles - protons and neutrons.

Six 'flavours' of quark have now been identified. (ref.) Suggesting the obvious qu…

Queen Mother's birthplaceplugin-autotooltip__plain plugin-autotooltip_bigQueen Mother's birthplace

Elizabeth Angela Marguerite Bowes-Lyon - a.k.a The Queen Mother (mother of the current UK Queen Elizabeth) was born on the 4th of August 1900. The place of her birth is so far …

"Radiation hormesis proposes that radiation exposure comparable to and just above the natural background level of radiation is not harmful but beneficial, while accepting that much higher levels of radiation are hazardous. Source

Note: This item is one of a special case - Known Unknowables

Radioactive decay is the process by which the nucleus of an unstable atom loses energy by emitting 'radiation' - which can be in the form of alpha particles, beta particles, gamma rays or …

Radioactive decay neutrino anomalyplugin-autotooltip__plain plugin-autotooltip_bigRadioactive decay neutrino anomaly

Around yr2000, researchers at Purdue University, US, noticed that some radioactive sources - which should decay completely randomly - sometimes show peaks and troughs (i.e. cyclic variations) in the averaged radiation they produce ove…

Radiotrophic fungi were first discovered in 2007 as black moulds growing inside and around the damaged Chernobyl Nuclear Power Plant in Ukraine. Subsequent research at the Albert Einstein College of Medicine showed that three melanin-containing fungi…

Raindrop formationplugin-autotooltip__plain plugin-autotooltip_bigRaindrop formation

"“When [an] ascending parcel of moist air reaches the condensation level, the initial mist of small, micron-size water droplets is formed, which are suspended in the air. In the super-saturated environment water droplets grow due to condensation of …

Random numbersplugin-autotooltip__plain plugin-autotooltip_bigRandom numbers

"“We can never decide for sure that a number is random, but what we can do is apply an increasing number of tests and treat our sequence of numbers as innocent until proved guilty.”

Source Colva Roney-Dougal, Senior Lecturer in Pure Mathematics at the…

'Reality' perceptionplugin-autotooltip__plain plugin-autotooltip_big'Reality' perception

"Most individuals hold strong, culturally-anchored beliefs that their particular reality is true, a viewpoint challenged by the observation that all such constructs are different.…

Reboxetineplugin-autotooltip__plain plugin-autotooltip_bigReboxetine

Reboxetine, sold under the brand name Edronax, is a drug marketed as a treatment for Major Depressive Disorder,Attention-Deficit / Hyperactivity Disorder (ADHD), and Panic Disorder - amongst others

It is said to work as a norepinephrine reuptake inhibitor (…

Redshift quantisationplugin-autotooltip__plain plugin-autotooltip_bigRedshift quantisation

'Cosmological Redshift' (with regard to cosmological objects such as galaxies, quasars etc) refers to the observed lowering of spectral frequencies caused by the high speed motion of astronomical objects away from an observer. Now routinely measur…

Referred itchplugin-autotooltip__plain plugin-autotooltip_bigReferred itch

Referred itch - also known as (Mitempfindung i.e. 'associated feeling') is the syndrome whereby an individual who scratches an itch in one part of the body (say, caused by an insect bite etc etc ) initiates another itch to appear in another region. It's u…

Relaxorsplugin-autotooltip__plain plugin-autotooltip_bigRelaxors

Relaxors is the name given to a group of ferroelectric materials which strongly change their shape in electric fields.

Examples include : lead magnesium niobate, lead magnesium niobate-lead titanate, lead lanthanum zirconate titanate, and lead scandium niobat…

REM (Rapid Eye Movement) sleepplugin-autotooltip__plain plugin-autotooltip_bigREM (Rapid Eye Movement) sleep

"“Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals and birds, distinguishable by random/rapid movement of the eyes, accompanied with low muscle tone throughout the body, and the propensity of the sleeper…

Respiratory rhythmplugin-autotooltip__plain plugin-autotooltip_bigRespiratory rhythm

The neural regulators and feedback mechanisms which control the rhythmic nature of breathing in mammals (and many other organisms) are currently the subject of intense research.

"Mammalian central pattern generators producing rhythmic movements exh…

Restless leg syndromeplugin-autotooltip__plain plugin-autotooltip_bigRestless leg syndrome

Restless legs syndrome, also known as Willis-Ekbom disease, is a common condition of the nervous system that causes an overwhelming and irresistible urge to move the legs. Estimates are that around 10% of people suffer from RLS at some stage in th…

Reye's syndromeplugin-autotooltip__plain plugin-autotooltip_bigReye's syndrome

"“Reye's syndrome (RS) is primarily a children's disease, although it can occur at any age. It affects all organs of the body but is most harmful to the brain and the liver - causing an acute increase of pressure within the brain and, often, massive ac…

Rheumatoid Arthritisplugin-autotooltip__plain plugin-autotooltip_bigRheumatoid Arthritis

Rheumatoid Arthritis (RA) is a chronic severe inflammatory disease believed to affect around 1% of the global population. It primarily affects joints, typically resulting in warm, swollen, and painful joints. Pain and stiffness often worsen followi…

Rheumatoid nodulesplugin-autotooltip__plain plugin-autotooltip_bigRheumatoid nodules

Rheumatoid nodules are found in approximately 25% of patients with definite or classic Rheumatoid Arthritis. They often form at inflamed joints (knuckles, elbows etc) and vary in size from 2 mm to 5 cm, They are usually painless.

It's not currently …

Rhinophymaplugin-autotooltip__plain plugin-autotooltip_bigRhinophyma

Rhinophyma (Greek “nose growth”) is a benign skin deformity characterized by tumorous growth leading to a large, bulbous, and erythematous (reddish) appearance of the nose.

At present its cause is classified as 'unknown' though it is often associated with…

Rhythm perceptionplugin-autotooltip__plain plugin-autotooltip_bigRhythm perception

Humans (and some other animals) have a sense of 'rhythm', i.e. the ability to detect and react with 'beats' - normally in musical compositions. Professional drummers can 'beat time' with accuracies of just a few milliseconds per beat (ref.

The Riemann hypothesisplugin-autotooltip__plain plugin-autotooltip_bigThe Riemann hypothesis

- was proposed by Bernhard Riemann (1859), and is a conjecture about the distribution of the zeros of the Riemann zeta function.

The Riemann hypothesis asserts that all interesting solutions of the equation :

 {\displaystyle \zeta (s)=\sum _{…

Ringstonesplugin-autotooltip__plain plugin-autotooltip_bigRingstones

"The ringstone is a distinctive type of artefact and miniature sculpture made in India during the approximate period of the Mauryan Empire (c. 322–185 BCE) and the following Sunga Empire (187–78 BCE). They are usually dated to the 3rd or 2nd centuries BCE. …

Rogue wavesplugin-autotooltip__plain plugin-autotooltip_bigRogue waves

Rogue waves are quasi-randomly occurring oceanic local waves which spontaneously form (and then disappear) as a result of interactions between the wavelengths of the 'normal' sea wave state.

They are defined as waves which have a height that is more than t…

Rongorongoplugin-autotooltip__plain plugin-autotooltip_bigRongorongo

Rongorongo is a system of glyphs discovered in the 19th century on Easter Island (a.k.a. Rapa Nui) that appears to be writing or proto-writing. More than 20 examples of the script, engraved onto hardwood plates and other objects, have so far been discovered.…

Rosaceaplugin-autotooltip__plain plugin-autotooltip_bigRosacea

"“Rosacea is a long-term skin condition that typically affects the face. It results in redness, pimples, swelling, and small and superficial dilated blood vessels. Often the nose, cheeks, forehead, and chin are most involved. A red enlarged nose may occur in s…

RuBisCO anomalyplugin-autotooltip__plain plugin-autotooltip_bigRuBisCO anomaly

RuBisCO (full name : Ribulose-1,5-bisphosphate carboxylase-oxygenase) is a crucial enzyme involved in the conversion of CO2 into sugars during photosynthesis. Without it, photosynthesising plants (and all other organisms which depend on plants, or requi…

Rufinamideplugin-autotooltip__plain plugin-autotooltip_bigRufinamide

Rufinamide (sold under the brand names Banzel, Inovelon and others) is an anti-convulsant medication used to treat seizure disorders - such as severe Epilepsy. It was approved by the US FDA in 2008,

Its 'mechanism of action' is currently unknown.

'Rule of Thumb' expression etymologyplugin-autotooltip__plain plugin-autotooltip_big'Rule of Thumb' expression etymology

Meaning “...an easily learned and easily applied procedure for approximately calculating or recalling some value, or for making some determination.”

"“The exact origin of the phrase is uncertain.The earliest known citation comes f…

The saccular lungplugin-autotooltip__plain plugin-autotooltip_bigThe saccular lung

The saccular lung, found in snakes, appears to have no role in breathing. It seems likely that it's a 'vestigial' organ from a time when the ancestors of snakes had two working lungs. Modern snakes have only one 'working' lung - which is suggested to…

Salt preferencesplugin-autotooltip__plain plugin-autotooltip_bigSalt preferences

Sodium deficiency is rare in humans, the physiological need for salt has been calculated at around 1.3 grams per day for an adult - but most people consume far more than this. Leading to the idea that there must be an inbuilt preference to consume more…

Sand dune formationplugin-autotooltip__plain plugin-autotooltip_bigSand dune formation

"Large swaths of Earth’s surface are covered in loose sediment. The grains that make up this sediment form fascinating bedforms from meandering riverbeds to wavy dunes, whose shapes are constantly changing as water or air currents move the grains.…

Spaceflight-associated neuro-ocular syndromeplugin-autotooltip__plain plugin-autotooltip_bigSpaceflight-associated neuro-ocular syndrome

Approximately 60% of the crew members of the International Space Station have reported altered visual acuity after long-duration exposure to micro-gravity.

"Astronauts on long-duration spaceflight missions may develop chan…

Sarcoidosisplugin-autotooltip__plain plugin-autotooltip_bigSarcoidosis

"“Sarcoidosis is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and brain. Any organ, how…

Sarcopeniaplugin-autotooltip__plain plugin-autotooltip_bigSarcopenia

"Sarcopenia, the decline in skeletal muscle mass and function without any underlying disease, is a major contributor to physical disability, poor quality of life, and death among the elderly [...] 40%–50% of individuals over 80 years of age suffer from thi…

The Sardine Runplugin-autotooltip__plain plugin-autotooltip_bigThe Sardine Run

"The term ‘sardine run’ is part of the cultural heritage of the South African nation and refers to a natural phenomenon that is well known to the general public but still poorly understood from an ecological perspective. This lack of understanding has …

Saturn's ringsplugin-autotooltip__plain plugin-autotooltip_bigSaturn's rings

"“There are two main theories regarding the origin of Saturn's inner rings. One theory, originally proposed by Édouard Roche in the 19th century, is that the rings were once a moon of Saturn (named Veritas, a Roman goddess who hid in a well) whose orbit…

Savant syndromeplugin-autotooltip__plain plugin-autotooltip_bigSavant syndrome

"Savant syndrome is a rare, but extraordinary, condition in which persons with serious mental disabilities, including autistic disorder, have some ‘island of genius’ which stands in marked, incongruous contrast to overall handicap. As many as one in 10…

Schizophreniaplugin-autotooltip__plain plugin-autotooltip_bigSchizophrenia

"“Schizophrenia is a mental disorder characterized by abnormal social behavior and failure to understand what is real. Common symptoms include false beliefs, unclear or confused thinking, auditory and visual hallucinations, reduced social engagement and …

Quote from Professor Roger Penrose speaking on BBC Radio 4 'Start the week - A Theory of Everything? 20th June 2016.

"“There is a deep paradox in quantum mechanics, it's a contradiction, and it's hardly ever pointed out as a contradiction…

Stony Coral Tissue Loss Diseaseplugin-autotooltip__plain plugin-autotooltip_bigStony Coral Tissue Loss Disease

Stony Coral Tissue Loss Disease (SCTLD) is a severe disease affecting corals. It was first noticed in 2014 around the Florida coast, and since then has spread to various other locations, especially in the Caribbean.

Sea level risesplugin-autotooltip__plain plugin-autotooltip_bigSea level rises

Climate change, along with the associated ice-shelf melting, contributes to sea level rise. However, the calculations linking the temperature records with ice melt leave an unexplained 12 cm/century rise in the actual levels - as measured around the wor…

Sea slopesplugin-autotooltip__plain plugin-autotooltip_bigSea slopes

In 1976 the US Defense Mapping Agency Topographic Center published a paper in International Hydrographic Review, Monaco, LIII (2) entitled On the Mystery of Mean Sea Level Slopes.

Researchers had found anomalies in the (averaged) sea levels along the US coa…

Sea Star Wasting Diseaseplugin-autotooltip__plain plugin-autotooltip_bigSea Star Wasting Disease

Sea Star Wasting Disease (SSWD) is a deadly disease affecting sea stars (a.k.a. starfishes) and other echinoderms - leading to mass mortalities.

At least 20 species are known to be affected.

To date, it has devastated sea star populations alo…

Serial position effectplugin-autotooltip__plain plugin-autotooltip_bigSerial position effect

The serial-position effect is the tendency to be able to recall the first and last items in a list more easily than those in the middle of a list.

It has been demonstrated and confirmed many times in different experiments (starting in 1913).

Sexual reproductionplugin-autotooltip__plain plugin-autotooltip_bigSexual reproduction

"“The maintenance of sexual reproduction in a highly competitive world has long been one of the major mysteries of biology given that asexual reproduction can reproduce much more quickly as 50% of offspring in sexual reproduction are males, unable …

Shinglesplugin-autotooltip__plain plugin-autotooltip_bigShingles

Shingles ( Herpes Zoster ) is a painful, and relatively long-lasting skin condition which affects around 1/3rd of the Western population at some stage in their lives. It's known to be associated with the 're activation' of the Varicella Zoster Virus (VZV) - wh…

Schnitzler syndromeplugin-autotooltip__plain plugin-autotooltip_bigSchnitzler syndrome

Schnitlzler syndrome (SchS) is a rare auto-inflammatory disorder characterised by a chronic urticarial rash (hives), and signs and symptoms of systemic inflammation - including fever, bone pain, joint pain, muscle pain, headache, fatigue, and loss o…

Shoe concealmentplugin-autotooltip__plain plugin-autotooltip_bigShoe concealment

Builders and archaeologists sometimes comes across old shoes (usually just one of a pair* which have been deliberately hidden in inaccessible places in the fabric of old buildings. Under floorboards, behind bricked-up fireplaces etc etc. A number of sc…

Sichuan papperplugin-autotooltip__plain plugin-autotooltip_bigSichuan papper

Sichuan pepper is a widely-used condiment. It has a citrus-like flavour and induces a tingling numbness in the mouth, which has been found to be due to the presence of a chemical called …

Sighingplugin-autotooltip__plain plugin-autotooltip_bigSighing

A sigh is defined as a kind of paralinguistic respiration in the form of a deep, audible, single exhalation of air out of the mouth or nose.

Sighing may have purely physiological triggers (see: Respiratory variability preceding and following sighs: A resetter …

Is the Universe a Computer Simulation?plugin-autotooltip__plain plugin-autotooltip_bigIs the Universe a Computer Simulation?

The simulation hypothesis was first published by Hans Moravec (of the Robotics Institute, Carnegie Mellon University, US) in 1998. See Simulation, Consciousness, Existence

Then, in 2003, Professor Nick Bostrom, Director of the F…

Singlet fission (photo-voltaics)plugin-autotooltip__plain plugin-autotooltip_bigSinglet fission (photo-voltaics)

Current photo-voltaic (PV) cells - e.g. solar panels for 'green' energy generation - have a quite low efficiency limit. If a high energy photon falls onto a PV cell, it generates the same electrical energy as a low energy photon. The '…

Health risks of sittingplugin-autotooltip__plain plugin-autotooltip_bigHealth risks of sitting

It was noted as far back as 1700 that 'Chairworkers' seemed tp have an increased risk for several diseases.

Since then, prolonged sitting (as a habit or for work purposes) has been found to increase the risks of developing heart disease, obesit…

Sjögren syndromeplugin-autotooltip__plain plugin-autotooltip_bigSjögren syndrome

Sjögren syndrome (SS) is a systemic long-term auto-immune condition which affects glands in the body's moisture-producing surfaces. Leading to dry eyes, dry mouth, dry skin, pain and fatigue. It can also strongly affect other organs, such as the lungs,…

Sleepplugin-autotooltip__plain plugin-autotooltip_bigSleep

"“The purposes and mechanisms of sleep are only partially clear and are the subject of intense research” Source Wikipedia"

Although extensive research in humans and animals has shown unequivocally that sleep is essential, the reasons why it's required are as y…

Sleepwalkingplugin-autotooltip__plain plugin-autotooltip_bigSleepwalking

"“Sleepwalking, also known as somnambulism or noctambulism, is a phenomenon of combined sleep and wakefulness. It is classified as a sleep disorder belonging to the parasomnia family. It occurs during slow wave sleep stage, in a state of low consciousness…

Supplementary Motor Areaplugin-autotooltip__plain plugin-autotooltip_bigSupplementary Motor Area

"“The supplementary motor area (SMA) is a part of the primate cerebral cortex that contributes to the control of movement. It is located on the midline surface of the hemisphere just in front of (anterior to) the primary motor cortex leg repre…

Sense of smell - Olfactionplugin-autotooltip__plain plugin-autotooltip_bigSense of smell - Olfaction

It's known that humans have about 10 cm2 of olfactory epithelium, with roughly 5 million sensory neurons.

Smells are detected due to the activation of neurons by airborne volatile chemicals and particles. Different chemicals affect different…

Snake evolutionplugin-autotooltip__plain plugin-autotooltip_bigSnake evolution

Current evidence suggests that snakes started to evolve less than 150 million years ago, but the debate about the evolutionary origins of snakes have not yet been definitively resolved, despite more than 100 years of research.

There are two competing t…

Snake venom evolutionplugin-autotooltip__plain plugin-autotooltip_bigSnake venom evolution

Although it's clear that venom systems can give significant advantages to predatory snakes and other animals, the evolutionary pathways which lead to their development are unknown.

"Oral venom systems evolved multiple times in numerous vertebrat…

Snapping hip syndrome (SHS)plugin-autotooltip__plain plugin-autotooltip_bigSnapping hip syndrome (SHS)

"SHS is a condition characterized by a palpable or audible “snapping” that occurs around the hip with movement. This condition is further described as either internal snapping hip syndrome (ISHS) or external snapping hip syndrome (ESHS). Wi…

Sneeze centerplugin-autotooltip__plain plugin-autotooltip_bigSneeze center

"“Experiments in cats identified a concentration of cells in the rostral dorsolateral pontomedullary area, stimulation of which causes sneezing indistinguishable from sneezing induced by natural peripheral stimuli.” Source: Localization of the “sneeze …

Snowball Earthplugin-autotooltip__plain plugin-autotooltip_bigSnowball Earth

The 'Snowball Earth' hypothesis - the idea that there was a period (sometime earlier than 650 million years ago) during which Earth was completely covered in ice - was developed to explain how (amongst other findings) glacial sedimentary rocks have been…

'Soda' and 'Sodium' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Soda' and 'Sodium' etymology

"“Soda (n.) late 15c., “sodium carbonate,” an alkaline substance extracted from certain ashes (now made artificially), from Italian sida (or Medieval Latin soda) “a kind of saltwort,” from which soda was obtained, of uncertain origin. Pe…

Sodium aurothiomalateplugin-autotooltip__plain plugin-autotooltip_bigSodium aurothiomalate

Sodium aurothiomalate (a.k.a. gold sodium thiomalate, and sold under the brand names Myocrisin, Myochrysine, Aurolate and others) is a gold compound, first tested in 1929, that is currently used to reduce the symptoms ofRheumatoid Arthritis

It ha…

Solar Cycleplugin-autotooltip__plain plugin-autotooltip_bigSolar Cycle

Scientists started to make records of sunspot activity in the mid 18th century, and by the mid 19th it was discovered that the number of spots (which are lower-temperature entry-and-exit points for magnetic flux lines penetrating the Sun's surface) varies o…

Solar flaresplugin-autotooltip__plain plugin-autotooltip_bigSolar flares

The first solar flare to be formally documented was recorded by astronomer Richard Carrington, who observed a 'white light' flare in September 1859 - projecting the image produced by an optical telescope, without filters. See: Wikipedia

However, the mecha…

Solar spiculesplugin-autotooltip__plain plugin-autotooltip_bigSolar spicules

"Spicules comprise one of the most fundamental components of the solar chromosphere. They appear to be jets of gas seen at the limb of the Sun in chromospheric spectral lines, and have been observed in Hα and other chromospheric spectral lines for over …

Sonoluminescenceplugin-autotooltip__plain plugin-autotooltip_bigSonoluminescence

Sonoluminescence is the emission of short bursts of light from imploding bubbles in a liquid when excited by sound. It was discovered in 1934 during sonar experiments at the University of Cologne. Light emissions are the result of the ultra-high temper…

Sopite syndromeplugin-autotooltip__plain plugin-autotooltip_bigSopite syndrome

"The sopite syndrome is a poorly understood response to motion. Drowsiness and mood changes are the primary characteristics of the syndrome. The sopite syndrome can exist in isolation from more apparent symptoms such as nausea, can last long; after nau…

The Sorites paradox is a philosophical problem dating from the time of (at least) Ancient Greece.

It relates to the problem of defining groups - specifically large groups. It has implications for the definitions of 'vagueness' 'fuzziness' 'blurriness' …

Spacetime atomsplugin-autotooltip__plain plugin-autotooltip_bigSpacetime atoms

The concept of (seemingly) smooth Einsteinian spacetime (three physical dimensions inextricably bound together with time as the fourth) has not yet been unified with the theoretical and observable 'granularity' of quantum physics.

As a means of integra…

Sparrow declineplugin-autotooltip__plain plugin-autotooltip_bigSparrow decline

Large declines of urban and suburban house sparrow (Passer domesticus) populations have been recorded in many towns and cities across Europe. In London, sparrow numbers fell by 60% between 1994 and 2004. The cause(s) of the decline is still not resolved…

Spasmodic dysphoniaplugin-autotooltip__plain plugin-autotooltip_bigSpasmodic dysphonia

"Spasmodic dysphonia, also known as laryngeal dystonia, is a disorder in which the muscles that generate a person's voice go into periods of spasm This results in breaks or interruptions in the voice, often every few sentences, which can make a per…

Definition of speciesplugin-autotooltip__plain plugin-autotooltip_bigDefinition of species

"“The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts. A species concept that works well for…

Species Extinction (mammalian)plugin-autotooltip__plain plugin-autotooltip_bigSpecies Extinction (mammalian)

Wikipedia maintains a list of mammalian species which are classified as possibly extinct. The list currently runs to more than 20 species which are presumed to have become extinct in the last 100 years or so.

But the verification is prob…

Speech perceptionplugin-autotooltip__plain plugin-autotooltip_bigSpeech perception

"Speech perception is the process by which the sounds of language are heard, interpreted and understood. The study of speech perception is closely linked to the fields of phonology and phonetics in linguistics and cognitive psychology and perception …

Sperm count controversyplugin-autotooltip__plain plugin-autotooltip_bigSperm count controversy

A 2017 report published in the journal Human Reproduction Update reviewed the results of over 2000 papers on sperm counts previously published (in English) between 1981 and 2013.

"“This comprehensive meta-regression analysis reports a signific…

Spider web decorationplugin-autotooltip__plain plugin-autotooltip_bigSpider web decoration

Several species of spiders construct conspicuous and elaborate 'decorative' features in their webs. The features are termed 'stabilimenta' - incorrectly, since they are now known that they are not related to structural stability.

Sporadic E or Es is an unusual, sporadically occurring form of enhanced radio-wave propagation.

It was discovered in the early days of VHF radio transmissions, and greatly increases the long-distance propagation of radio waves in the region of 2…

Squeaky Sandplugin-autotooltip__plain plugin-autotooltip_bigSqueaky Sand

Sand on some beaches and dunes emits a distinct 'squeaking' sound when moved under pressure. Videos here

It only affects certain types of sand - more rounded and drier grains generally don't squeak (as much). The underlying acoustic mechanism is as yet un…

Staebler–Wronski effectplugin-autotooltip__plain plugin-autotooltip_bigStaebler–Wronski effect

The Staebler–Wronski effect was first described in 1977. It refers to the unexplained drop-off in the efficiency of silicon-based photovoltaic cells - as used in solar panels etc - after a few hundred hours of light exposure (So-called 'Light S…

Star formationplugin-autotooltip__plain plugin-autotooltip_bigStar formation

Many decades of intensive astronomical research has revealed a wealth of data on how stars form.

"“Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as “stellar nurseries

Static electricityplugin-autotooltip__plain plugin-autotooltip_bigStatic electricity

Static electricity has been investigated for more than 2 thousand years. The earliest written scientific accounts of 'static electricity' are believed to be those of Thales of Miletus at around 600BC. He thought (correctly, but for the wrong reasons)…

'Strange' matterplugin-autotooltip__plain plugin-autotooltip_big'Strange' matter

'Normal' matter has atomic nuclei that are entirely composed of 'up' and 'down' Quarks. It's known, however, that there are, in total, six types of quark - one of which is known as the 'strange' quark.

Multiple observations have shown that in isolati…

Stretchingplugin-autotooltip__plain plugin-autotooltip_bigStretching

"“Pandiculation [stretching] is the involuntary stretching of the soft tissues, which occurs in most animal species and is associated with transitions between cyclic biological behaviors, especially the sleep-wake rhythm (Walusinski, 2006). Yawning is consi…

Stromulesplugin-autotooltip__plain plugin-autotooltip_bigStromules

"“A stromule is a microscopic structure found in plant cells. Stromules (stroma-filled tubules) are highly dynamic structures extending from the surface of all plastid types, including proplastids, chloroplasts, etioplasts, leucoplasts, amyloplasts, and chro…

Supersymmetry (SUSY)plugin-autotooltip__plain plugin-autotooltip_bigSupersymmetry (SUSY)

Supersymmetry (colloquially known as SUSY) is a principle that proposes that each Boson atomic particle (e.g. photons) has a corresponding Fermion particle (e.g. electrons), and vice versa. If such particles were found to exist, several mathematica…

Synesthesiaplugin-autotooltip__plain plugin-autotooltip_bigSynesthesia

Synesthesia is a neurological phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway.

Widely documented examples include individuals who reliably and consiste…

T Helper Cellsplugin-autotooltip__plain plugin-autotooltip_bigT Helper Cells

"“The T helper cells (Th cells), also known as CD4+ cells, are a type of T cell that play an important role in the immune system, particularly in the adaptive immune system. They help the activity of other immune cells by releasing T cell cytokines. The…

Tail Weaponisationplugin-autotooltip__plain plugin-autotooltip_bigTail Weaponisation

Weaponry, for the purpose of combat or predator defence, is one of the most widespread animal adaptations.

A 2018 paper in Proceedings of the Royal Society, Biological Sciences points out that tail weaponisation (flails, spikes, bats and clubs etc) …

Taillight sharkplugin-autotooltip__plain plugin-autotooltip_bigTaillight shark

The Taillight Shark (Euprotomicroides zantedeschia) is a rarely found species of shark in the family Dalatiidae - the only member of its genus.

To date. only four specimens have been found, from the deep oceanic waters in the southern Atlantic Ocean an…

Takotsubo syndromeplugin-autotooltip__plain plugin-autotooltip_bigTakotsubo syndrome

Takotsubo syndrome (TTS) is also known as Broken Heart Syndrome, Takotsubo cardiomyopathy, Stress cardiomyopathy and Apical ballooning syndrome. It's a temporary heart condition linked to stress - which can be physical, emotional or induced by illne…

Tropical Ataxic Neuropathy (TAN)plugin-autotooltip__plain plugin-autotooltip_bigTropical Ataxic Neuropathy (TAN)

"Tropical ataxic neuropathy, which is prevalent in the tropics causes significant disability as well as increased mortality and remains an enigmatic disease with no effective treatment or cure, even a century after its identification.

Tarantismplugin-autotooltip__plain plugin-autotooltip_bigTarantism

Tarantism is a form of hysteric 'dancing' behaviour, popularly believed to result from the bite of the Wolf Spider and/or the Mediterranean Black Widow or Steppe Spider.

However, no link between such bites and the behaviour of tarantism has ever been demonst…

Tasteplugin-autotooltip__plain plugin-autotooltip_bigTaste

Current theory lists five main taste receptor categories : sweetness, bitterness, sourness, saltiness, and umami. Source: Wikipedia

The physical mechanisms for detection of each of these main flavour types have been extensively investigated, and the correspondi…

TBI Dementiaplugin-autotooltip__plain plugin-autotooltip_bigTBI Dementia

Traumatic Brain Injuries (TBIs) are strongly suspected as being linked with the development of early onset dementia. This has implications for those who participate in combative sports (e.g. rugby, boxing etc.).

However, biological mechanisms which lead t…

Telescoping effectplugin-autotooltip__plain plugin-autotooltip_bigTelescoping effect

The Telescoping Effect, first named in 1964, refers to the tendency that many people have for mis-judging the time at which events have happened. In general, recent events are judged as being more remote than they were, and distant events as being mo…

Terrestrial gamma-ray flashesplugin-autotooltip__plain plugin-autotooltip_bigTerrestrial gamma-ray flashes

Terrestrial gamma-ray flashes (TGFs) were first reported using data from the Burst and Transient Source Experiment (BATSE) onboard NASA's Compton Gamma-Ray Observatory (CGRO) in 1994.

The short duration (0.2 to 3.5 milliseconds) atmospher…

Sandbox test pageplugin-autotooltip__plain plugin-autotooltip_bigSandbox test page

This page is for testing syntax and layout etc etc

Testosterone and aggressionplugin-autotooltip__plain plugin-autotooltip_bigTestosterone and aggression

"“Little is known about the neurobiological pathways through which testosterone promotes aggression or about the people in whom this effect is observed.”"

A 2019 study published in the journal Psychological Science describes experiments at…

Tetrahedraneplugin-autotooltip__plain plugin-autotooltip_bigTetrahedrane

Tetrahedrane is a simple 'proposed' hydrocarbon in the family of 'platonic hydrocarbons'

It has a very simple chemical formula is (C4H4) and calculations show that it should be relatively stable. Methods for making the compound are as yet unknown (altho…

Transient global amnesia (TGA)plugin-autotooltip__plain plugin-autotooltip_bigTransient global amnesia (TGA)

"Transient global amnesia (TGA) is a neurological disorder whose key defining characteristic is a temporary but almost total disruption of short-term memory with a range of problems accessing older memories. A person in a state of TGA ex…

Thalidomideplugin-autotooltip__plain plugin-autotooltip_bigThalidomide

Thalidomide was first marketed in 1957 as a multi-use sedative. It later became popular to treat Morning Sickness in pregnancy. By 1961, it was realised that the drug was causing severe malformation of the limbs in infants.

The figures for the total numb…

Thermogenic plantsplugin-autotooltip__plain plugin-autotooltip_bigThermogenic plants

More than 900 plant species are known to be able to internally heat themselves. A famous example is the Skunk Cabbage, Symplocarpus foetidus, which is capable of maintaining an internal temperature of around 20 °C even when the ambient temperature dr…

Thermoregulationplugin-autotooltip__plain plugin-autotooltip_bigThermoregulation

"“The core temperature of a human is regulated and stabilized primarily by the hypothalamus, a region of the brain linking the endocrine system to the nervous system, and more specifically by the anterior hypothalamic nucleus and the adjacent preoptic…

Thermotropismplugin-autotooltip__plain plugin-autotooltip_bigThermotropism

Many plants are known to respond vigorously to changes in temperature. (A commonly cited example is the Rhododendron plant, which curls its leaves in response to low temperatures.)

Experiments have shown that the thermotropic effects are relative to prev…

Third-hand smokeplugin-autotooltip__plain plugin-autotooltip_bigThird-hand smoke

Note: This item is currently in the Proposed Content section

The health hazards of inhaling second-hand tobacco smoke are now well documented. But data are still lacking regarding quantifying the hazards (if any) of third-hand smoke.

Thoughtplugin-autotooltip__plain plugin-autotooltip_bigThought

It seems clear that thoughts involve brain-neurones, because damage to (or a reduction in the number of) neurones makes rational thought more difficult. But, likememory, the exact physical and/or biological micro-mechanisms which lead to the formation of ‘thou…

Sums of three cubesplugin-autotooltip__plain plugin-autotooltip_bigSums of three cubes

Is there a number (that is not 4 or 5 modulo 9) that cannot be expressed as a sum of three cubes?

Put another way :

"In the mathematics of sums of powers, it is an open problem to characterize the numbers that can be expressed as a sum of three c…

Thylacineplugin-autotooltip__plain plugin-autotooltip_bigThylacine

The Thylacine (Thylacinus cynocephalus) also known as the Tasmanian Tiger, or Marsupial Wolf is believed to have gone into extinction in 1936 when the last known specimen died at Hobart Zoo, Australia. Competition with dingoes, and bounties paid to hunters (…

Ticklingplugin-autotooltip__plain plugin-autotooltip_bigTickling

The sensation of tickling has been scientifically investigated for more than 100 years (and unscientifically for many centuries before that) There are many unknowns associated with tickling in general. e.g.

* Why are some body areas more ticklish than others…

Time Awarenessplugin-autotooltip__plain plugin-autotooltip_bigTime Awareness

"“Anticipating events that will happen in the future is among the most important functions the brain performs. Indeed, it has been increasingly stressed that learning and memory are prospective brain functions; that is, they are only adaptive to the ext…

Arrow of Timeplugin-autotooltip__plain plugin-autotooltip_bigArrow of Time

A term coined in 1927 by the British astronomer Arthur Eddington to describe the “one-way direction” or “asymmetry” of time.

For most people, the notion that time passes only in one direction is a given. There are multiple reasons for taking this point o…

Tinnitusplugin-autotooltip__plain plugin-autotooltip_bigTinnitus

"Tinnitus is the perception of noises in the head and/or ear which have no external source. It derives from the Latin word for ringing and those living with the condition may have to endure a ringing, buzzing, hissing, whistling or other noise. The sensation …

Tip of the tongueplugin-autotooltip__plain plugin-autotooltip_bigTip of the tongue

"“Tip of the tongue (or TOT) is the phenomenon of failing to retrieve a word from memory, combined with partial recall and the feeling that retrieval is imminent. The phenomenon's name comes from the saying, “It's on the tip of my tongue.

Transcranial Magnetic Stimulationplugin-autotooltip__plain plugin-autotooltip_bigTranscranial Magnetic Stimulation

"“Depression is expected to become the leading cause of disabilities worldwide with about 20% of the population suffering from a mood disorder at least once in a lifetime (Kessler et al., 2005; de Graaf et al., 2012). Even more alarmi…

"“Toad (n.) c. 1300, from late Old English tadige, tadie, of unknown origin and according to OED with no known cognates outside English. Applied to loathsome persons from 1560s. Toad-strangler “heavy rain” is from 1919, U.S. Southern dialectal.

Tolmetinplugin-autotooltip__plain plugin-autotooltip_bigTolmetin

Tolmetin, a.k.a. Tolectin is a nonsteroidal anti-inflammatory drug (NSAID) of the heterocyclic acetic acid derivative class.

It was developed in the 1970's, and is used to treat conditions such as osteoarthritis, Rheumatoid Arthritis, and Ankylosing Spondylit…

Tonic Immobilityplugin-autotooltip__plain plugin-autotooltip_bigTonic Immobility

"“Tonic Immobility (TI) is a reversible coma-like stasis inherent to a variety of terrestrial and aquatic taxa, including elasmobranchs [sharks] yet virtually nothing is known about its underlying neurological and physiological processes in any taxa…

Descriptions of the atmospheric mechanisms which cause tornados to form ('tornadogenesis') are currently unclear. Similar problems exist in full explanations of dust-devils, waterspouts, landspouts and hurricanes. Currently available computer models (such as V…

Touchplugin-autotooltip__plain plugin-autotooltip_bigTouch

Although a huge body of research has investigated how 'touch' sensations work in mammals (especially humans), the 'mechano-transduction' channels are still not fully explained. In particular, mechanisms providing the 'pleasant' aspects of touch have not yet been …

Tourette syndromeplugin-autotooltip__plain plugin-autotooltip_bigTourette syndrome

Tourette syndrome (TS or simply Tourette's) is a common neuropsychiatric disorder which usually starts in childhood and is characterized by multiple motor tics and at least one vocal tic. These tics characteristically wax and wane, can be suppressed t…

Toxoplasmosisplugin-autotooltip__plain plugin-autotooltip_bigToxoplasmosis

Toxoplasmosis is a parasitic disease caused by infections of the protozoan parasite Toxoplasma gondii.

It is extremely widespread in the human population. Infection rates vary in various regions of the world - but it's currently estimated that about 40 -…

Transient synovitis (of the hip)plugin-autotooltip__plain plugin-autotooltip_bigTransient synovitis (of the hip)

Transient synovitis of the hip (a.k.a. Toxic synovitis,Transitory coxitis, Coxitis fugax, Acute transient epiphysitis, Coxitis serosa seu simplex, Phantom hip disease, Observation hip and Irritable hip) is a condition which causes hip p…

Travelling salesman problemplugin-autotooltip__plain plugin-autotooltip_bigTravelling salesman problem

Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each city exactly once and returns to the origin city?

Computing algorithms (using so-called 'Monte Carlo' processes) can …

Triboluminescent tapeplugin-autotooltip__plain plugin-autotooltip_bigTriboluminescent tape

When rolls of transparent adhesive tape are peeled, the relative motion between the two separating surfaces can produce electromagnetic radiation - an example of triboluminescence.

It can be seen as visible light, but the peeling action can also …

Trigger fingerplugin-autotooltip__plain plugin-autotooltip_bigTrigger finger

Trigger finger (a.k.a. Stenosing tenosynovitis and Historicopous ) is a disorder characterized by the (sometimes painful) catching or locking of a finger, or the thumb. The name is given because of the popping sound made by the affected finger when flex…

Triptansplugin-autotooltip__plain plugin-autotooltip_bigTriptans

Triptans, sold under the brandnames Imitrex, Zomig, Amerge, Maxalt, Relpax and others, are a range of highly effective drugs used to treat Migraine and Cluster headache.

The mechanism of action of the drug(s) has been debated since the 1980s.

It's currently …

The Trojan Warsplugin-autotooltip__plain plugin-autotooltip_bigThe Trojan Wars

"The ancient Greeks believed that Troy was located near the Dardanelles and that the Trojan War was a historical event of the 13th or 12th century BC, but by the mid-19th century AD, both the war and the city were widely seen as non-historical. In 1868…

Trypophobiaplugin-autotooltip__plain plugin-autotooltip_bigTrypophobia

Trypophobia - a fear of (clusters of small) holes - was first formally described by Geoff G. Cole and Arnold J. Wilkins in their paper for Psychological Science August 2013 entitled

'Fear of Holes'

"“The image most often reported as inducing the phobia…

TSEs (Transmissible Spongiform Encephalopathies)plugin-autotooltip__plain plugin-autotooltip_bigTSEs (Transmissible Spongiform Encephalopathies)

Transmissible Spongiform Encephalopathies (TSEs) are severe degenerative diseases which affect a wide range of mammals - they include bovine spongiform encephalopathy (BSE or “Mad Cow Disease”), fatal familial insomnia, …

Tully Monsterplugin-autotooltip__plain plugin-autotooltip_bigTully Monster

"“Tullimonstrum, colloquially known as the Tully Monster, is an extinct genus of soft-bodied bilaterian that lived in shallow tropical coastal waters of muddy estuaries during the Pennsylvanian geological period, about 300 million years ago.

Turbulenceplugin-autotooltip__plain plugin-autotooltip_bigTurbulence

Due to lack of understanding of precise underlying mechanisms, turbulent flow in liquids, gases and powders (etc) cannot be exactly predicted.

There is as yet no theorem relating Reynolds Number to turbulence.

"Quote from: Prof. Richard Feynman - “

Marine Turtle Migrationplugin-autotooltip__plain plugin-autotooltip_bigMarine Turtle Migration

Several species of marine turtle accurately migrate thousands of kilometers for nesting. Some species return to the exact beach where they were hatched. There are various proposed explanations for the behaviour, including magnetic navigation. Bu…

Twinning rate and maternal age in humansplugin-autotooltip__plain plugin-autotooltip_bigTwinning rate and maternal age in humans

Multiple births occur in most mammals, with varying frequencies. In humans, multiple births are relatively uncommon (aside from fertility treatments). But the incidence tends to rise with the increasing age of the mother - altho…

Ulam's packing conjectureplugin-autotooltip__plain plugin-autotooltip_bigUlam's packing conjecture

When packing convex identical 3-dimensional objects into a defined space, is a sphere the most 'efficient' shape when considering the amount of free space in the gaps?

According to the conjecture, the sphere is the convex solid which forces t…

Ulcerative colitisplugin-autotooltip__plain plugin-autotooltip_bigUlcerative colitis

"Ulcerative colitis (UC) is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary symptoms of active disease are abdominal pain and diarrhoea mixed with blood. Weight loss, fever, and anaemia may also occ…

Ultraluminous X-ray burstsplugin-autotooltip__plain plugin-autotooltip_bigUltraluminous X-ray bursts

Ultraluminous X-ray bursts are newly (2016) discovered, and as yet unexplained sources of X-rays which have been observed in nearby galaxies.

"“The mysterious sources regularly emit X-rays, but have been observed spontaneously flaring up an…

Ultratrace elementsplugin-autotooltip__plain plugin-autotooltip_bigUltratrace elements

Ultratrace elements are chemical elements, derived from diet, which appear to play significant - and sometimes essential - biological roles in animals, including humans.

They typically comprise less than one microgram per gram of a given organism (…

Expansion of the universeplugin-autotooltip__plain plugin-autotooltip_bigExpansion of the universe

Note: This item belongs to a special case - Known Unknowables

Current cosmological theory, backed up by many diverse observations, suggests that the universe is not only expanding, but that the speed of expansion is accelerating

Universe shape and sizeplugin-autotooltip__plain plugin-autotooltip_bigUniverse shape and size

The 'Observable Universe' is limited by the speed of light and the length of time that it has been in existence. It's possible that the 'Observable Universe' is the real size, or, because light has a finite speed, there may be more of the univer…

Vacuum energyplugin-autotooltip__plain plugin-autotooltip_bigVacuum energy

Quantum physics, and the widely accepted and experimentally tested Heisenberg Uncertainty Principle implies that no 'vacuum' can be truly empty. At all times, innumerable quantised 'virtual particles' must be coming into existence and then disappearing.…

'Vague' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Vague' etymology

"“Vague (adj.) “uncertain as to specifics,” 1540s, from Middle French vague “empty, vacant; wild, uncultivated; wandering” (13c.), from Latin vagus “strolling, wandering, rambling,” figuratively “vacillating, uncertain,

Valproateplugin-autotooltip__plain plugin-autotooltip_bigValproate

"Valproate (VPA) and its valproic acid, sodium valproate, and valproate semisodium forms are medications primarily used to treat epilepsy and bipolar disorder and prevent migraine headaches. They are useful for the prevention of seizures in those with absenc…

Vascular dementiaplugin-autotooltip__plain plugin-autotooltip_bigVascular dementia

"Vascular dementia (VD) is the second most common cause of dementia following Alzheimer’s disease (AD). The major symptoms of VD including memory loss, language deficits and impairment of executive functions. Its specific etiology and pathogenesis re…

Venous Thrombosisplugin-autotooltip__plain plugin-autotooltip_bigVenous Thrombosis

Venous Thrombosis - blood clots which from in veins (as opposed to arteries) - are relatively common and potentially very dangerous (e.g. DVT).

Although it's firmly established that three factors (hypercoagulability, hemodynamic changes and endothe…

Venus Flytrap mechanismplugin-autotooltip__plain plugin-autotooltip_bigVenus Flytrap mechanism

The Venus Flytrap (Dionaea muscipula) is a well-known carnivorous plant native to the sub-tropical wetlands of the US.

The 'trap' structure snaps shut when insects or spiders touch specialised 'trigger hairs' on the trap's upper surface.

The origins of virusesplugin-autotooltip__plain plugin-autotooltip_bigThe origins of viruses

The evolutionary origins of viruses is disputed. Although they don't leave a fossil record it's known that they are ancient (at around 4.5 billion years old).

It's not known, however, whether they evolved from cellular lifeforms, or

Visual Accommodationplugin-autotooltip__plain plugin-autotooltip_bigVisual Accommodation

Accommodation is the process by which the eye changes optical focus (from distant to near and vice versa) due to muscular re-shaping of the eye's lens. It can either be automatic or under voluntary control.

The mechanism involves a smooth muscle g…

Visual Snow syndromeplugin-autotooltip__plain plugin-autotooltip_bigVisual Snow syndrome

"Patients with so-called ‘visual snow’ describe a persistent disturbance in the entire visual field resembling the ‘static’ or ‘snow’ of a badly-tuned analogue television. The symptoms are continuous and can persist over years. Although many prima…

Vitamin C deficitsplugin-autotooltip__plain plugin-autotooltip_bigVitamin C deficits

Humans, some non-human primates, guinea pigs, bats, capybara and some birds and fish have lost the ability to synthesize vitamin C - apparently due to a gene mutation defect. Because vitamin C is required for a range of essential metabolic reactions,…

Vitiligoplugin-autotooltip__plain plugin-autotooltip_bigVitiligo

"“Vitiligo, an acquired pigmentary disorder of unknown origin, is the most frequent cause of depigmentation worldwide, with an estimated prevalence of 1%. The disorder can be psychologically devastating and stigmatising, especially in dark skinned individuals…

The Voynich Manuscriptplugin-autotooltip__plain plugin-autotooltip_bigThe Voynich Manuscript

"“The Voynich manuscript is an illustrated codex hand-written in an unknown writing system. The vellum on which it is written has been carbon-dated to the early 15th century (1404–1438)

[...] The Voynich manuscript has been studied by many prof…

Wacker processplugin-autotooltip__plain plugin-autotooltip_bigWacker process

The Wacker process or the Hoechst-Wacker process refers to the oxidation of ethylene to acetaldehyde in the presence of a palladium(II) chloride catalyst.

It was originally developed in 1956 by the German chemical firm Wacker Chemie,

Water - its originplugin-autotooltip__plain plugin-autotooltip_bigWater - its origin

One obvious difference between Earth and other planets in the Solar System is that it's 70% covered in liquid water. There are at least five major (and very different) theories proposing the origins of such a large volume of water (estimated at 1.3 b…

Water molecule chemical bondingplugin-autotooltip__plain plugin-autotooltip_bigWater molecule chemical bonding

Debates about an exact model of the chemical bonding of the H20 molecule have been running for more than 50 years.

There are two main models, the Molecular Orbital Theory and the Valence Bond Theory (described at Wikipedia).

Neither th…

Water clustersplugin-autotooltip__plain plugin-autotooltip_bigWater clusters

Water has a long list of 'anomalous' physical (and chemical) properties (list here, archived from London Southbank University). Most are now fairly well understood - but there is currently no overall model to explain all of its unusual properties

Medicinal drug pollution in waterwaysplugin-autotooltip__plain plugin-autotooltip_bigMedicinal drug pollution in waterways

"“Despite having known for almost two decades that pharmaceuticals are commonly found in aquatic environments (Kolpin et al. 2002), we are only beginning to understand the potential implications of these synthetic chemicals on aqu…

Gastrointestinal weight-loss surgeryplugin-autotooltip__plain plugin-autotooltip_bigGastrointestinal weight-loss surgery

Gastrointestinal weight-loss surgery, also known as Gastric Bypass surgery refers to surgical processes in which the stomach is divided and reduced (usually by more than 90%), and then the small intestine is rearranged to connect to…

Whale Songplugin-autotooltip__plain plugin-autotooltip_bigWhale Song

Several species of whales - notably the male Humpback Whales (Megaptera novaeangliae) - engage in so-called 'singing' displays. (The songs were first noted by undersea microphone systems installed to detect the movements of submarines.)

"

Whale-song pitch declineplugin-autotooltip__plain plugin-autotooltip_bigWhale-song pitch decline

A 2009 paper from the Scripps Institution of Oceanography, published in the journal Endangered Species Research (ESR) described the drop in musical pitch (31%) of songs of the Blue Whale (Balaenoptera musculus) over a period of 50 years or so.

Whale spermaceti organplugin-autotooltip__plain plugin-autotooltip_bigWhale spermaceti organ

The Spermaceti organ found in the heads of sperm whales produces an oily/waxy substance. There can be up to 2 tonnes of oil in each animal. It's also produced in smaller quantities in some other whale species.

Before whaling was made illegal (in…

Invention of the wheelplugin-autotooltip__plain plugin-autotooltip_bigInvention of the wheel

The time and place of the invention of the wheel + axle*, as a means of making transport easier, is disputed.

The oldest indirect evidence of wheeled movement was found in the form of miniature clay wheels north of the Black Sea before 4000 B.C.…

Wolf domestication > dogsplugin-autotooltip__plain plugin-autotooltip_bigWolf domestication > dogs

The entire spectrum of domestic dogs are believed to have originated from Grey Wolves. The precise details of when, where, and how are unknown.

A 2021 review study suggests that dogs and humans share a correlated history of population diverge…

'Wonky' etymologyplugin-autotooltip__plain plugin-autotooltip_big'Wonky' etymology

"Wonky (adj.) “shaky, groggy, unstable,” 1919, of unknown origin. German prefix wankel- has a similar sense. Perhaps from surviving dialectal words based on Old English wancol “shaky, tottering” Source: Etymology online"

Note: The Online Etymology D…

Wookey Hole Cave Systemplugin-autotooltip__plain plugin-autotooltip_bigWookey Hole Cave System

Note: This item is currently in the 'Proposed Content' section

The Wookey Hole Caves are a series of limestone caves in the village of Wookey Hole on the southern edge of the Mendip Hills in Somerset, England.

The full extent of the cave syste…

Cosmological wormholesplugin-autotooltip__plain plugin-autotooltip_bigCosmological wormholes

"“Wormholes are hypothetical entities that show up in theoretical analyses of Einstein's theory of gravity (general relativity). Nobody has yet seen a wormhole, nor are we certain that they exist, but they seem to show up so easily when we do ca…

Wrinkly Fingersplugin-autotooltip__plain plugin-autotooltip_bigWrinkly Fingers

Most people have experienced wrinkly finger syndrome - when fingertips turn paler and wrinkle after prolonged exposure to water.

There are two theories on how the wrinkles develop - the ‘shrink’ model and the ‘swell’ model. Neither theory alone provide…

Writer's Crampplugin-autotooltip__plain plugin-autotooltip_bigWriter's Cramp

Writer's cramp, also called mogigraphia and scrivener's palsy, is a disorder which involves cramps or spasms of muscles of the hand and/or forearm.

"“Writer's cramp is a focal dystonia of the hand in which an individual, usually someone whose occupatio…

Wurtz Fittig reactionplugin-autotooltip__plain plugin-autotooltip_bigWurtz Fittig reaction

The Wurtz Fittig reaction is the name given to the process for the preparation of alkylated aromatic compounds by sodium‐mediated coupling of an alkyl and an aryl halide. It was first noted in 1860.

It has been used in the preparation of 'organos…

Yardangsplugin-autotooltip__plain plugin-autotooltip_bigYardangs

Yardangs are enigmatic wind-parallel ridges found in arid environments. They often form downwind of rocks in sandy environments. They can be unusually stable structures, given their sandy / dusty composition, and the fact that the wind which forms them can al…

Yawningplugin-autotooltip__plain plugin-autotooltip_bigYawning

The physical and psychological sequences which occur during the yawning process have been widely studied. Nevertheless, the reasons for yawning are disputed and unclear - as is identifying an evolutionary reason to explain the need for it.

"

Yipsplugin-autotooltip__plain plugin-autotooltip_bigYips

'The yips’ is a psycho-neuro-muscular impediment affecting sportspersons. Symptoms include jerks, tremors, staggers and freezing, and may cause performance problems. The condition can occur suddenly and without apparent explanation - usually in mature athletes wit…

Zebra stripesplugin-autotooltip__plain plugin-autotooltip_bigZebra stripes

"“Despite over a century of interest, the function of zebra stripes has never been examined systematically.”"

The quote is from an extensive 2014 study published in Nature Communications. The study examined the five prominent theories regarding the zeb…

Ziegler-Natta catalystsplugin-autotooltip__plain plugin-autotooltip_bigZiegler-Natta catalysts

The Heterogeneous Ziegler-Natta (ZN) catalytic process was discovered in the 1950s and is still a fundamental part of the manufacture of many plastics - e.g. polyethylene (polythene) and polypropylene. Earning the creators the 1963 Nobel Prize …

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