open-index/open-wikipedia-markdown huggingface dataset:
W

**W** is the twenty-third (number 23) letter in the Latin alphabet. Its name is pronounced "double-u". It is the only letter whose name has three syllables in English.

In words like *away*, *what*, *write* and *women*, the letter W is a consonant (semivowel). In words like *draw*, *few* and *low*, the letter W is a vowel.

## Meanings for W
* On calendars, W is most times a short letter for Wednesday.
* In chemistry, W is the symbol for tungsten, after its German name, *Wolfram*.
* In news story writing, the "five W's" stand for *who*, *what*, *when*, *where* and *why*.
* In electricity, W stands for watts
* In particle physics, W stands for the W boson. Some words sound as if they start with an R, but they start with a silent W, like wrong, and wreck, which is why you never hear the W at the beginning of these words, as you can see. Note that only the R sound can be heard, because it comes after the silent W starting the words.
* In slang, W stands for Win.
## Notes
## Other websites
New York University

**New York University**, also known as **NYU**, is a research university in New York City. It is the largest private university in the United States, and is highly regarded in the nation as well as around the world.
## Rankings
In 2020, it was ranked as the 11th best university in the United States by the QS World University Rankings: USA, and as the 28th best university in the world by U.S. News & World Report. In addition, NYU is highly ranked in the fields of Law, Medicine, Mathematics, Business, Psychology, Communications, Performing Arts, Film, Economics, and Philosophy.
## History
The university was founded as *University of the City of New York* in 1831 by a prominent group of New York City residents led by then United States Secretary of the Treasury, Albert Gallatin. The school was officially renamed New York University in 1896.

37 Nobel Prize winners have been produced by NYU, the 12th most in the United States and 19th most in the world. Three heads of state attended NYU: Ma Ying-jeou of the Republic of China, Ephraim Katzir of Israel, and Guillermo Endara of Panama. Many American politicians also attended NYU, including Bill de Blasio, Carol Bellamy, and Rudy Giuliani. Many successful actors and movie directors attended NYU, including Martin Scorcese, Angelina Jolie, Alec Baldwin, Spike Lee, Ang Lee, Mahershala Ali, Woody Allen, and Adam Sandler. Other famous alumni include the creator of the polio vaccine Jonas Salk, singer Lady Gaga, Twitter founder Jack Dorsey, author Suzanne Collins, and former special counsel Robert Mueller.

NYU is one of the places where 5G was created, as well as where many of the foundations of modern electromagnetic theory were discovered.
## Campus
In addition to its main campus in New York City, NYU also has degree-granting campuses in Abu Dhabi and Shanghai. NYU Abu Dhabi has produced more Rhodes Scholars per student than any other university in the world. 

## References
Creative Commons licenses

The **Creative Commons licenses** relates to the name of several copyright licenses released on December 16, 2002. The licenses were released by *Creative Commons*, a United States nonprofit corporation. Everybody can put their own creations under these licenses.

There are four basic license conditions. A simple overview of these four:

* **Attribution** (BY): Allow others to copy, distribute, display and perform the work and evolved versions of it. They must give the original creator credit for the work. 
* **Noncommercial** (NC): Allow others to copy, distribute, display and perform the work and evolved version of it. They are not allowed to make money with it. 
* **No Derivative Works** (ND): Allow others to copy, distribute, display and perform  the work. They are not allowed to change the work into something else.
* **Share Alike** (SA): Allow others to distribute evolved works only when they use the same license. See also copyleft.

It is possible to combine the license elements to allow people to use a work under certain conditions. For example, a combination of the first and fourth is called "CC BY-SA". This stands for "Creative Commons Attribution-ShareAlike". With this license other people can use the work for free, but they must give credit to the original creator, and when they make something new with the work they must give it the same "CC BY-SA" license.

## Criticism 
The Free Software Foundation thinks that the Creative Commons system is confusing, because people often forget to tell which of the licenses they use. Instead they suggest to use the Free Art license.

## Related pages
* Creative Commons
* Copyleft
* Free content

## References 
* *Portions of this article are taken from the Creative Commons website, published under the Creative Commons Attribution License v1.0*

## Other websites 
* The full selection of licenses
* Creative Commons web site
Alpha male

An **alpha male** is the top-ranking male in a mammalian social group.

## Origin
Some animals live in a social structure where the most powerful male in the group is decided by either fights or very aggressive battles that sometimes end in death (in the wild). The current alpha male must defend his position from younger members. When he is too old or not strong enough to win, he loses his position in the group. Sometimes, he will die or be forced to leave the group.

The result of this is that the alpha male usually has more opportunity to mate with the available females. This system developed because strong males will produce young which have a better chance for survival.

## Examples
Some animal groups which may have alpha males:
* Lions
* Apes: chimpanzees, gorillas and orangutans
* Horses
* Deer

### Humans
**Alpha male** can also refer to a high-ranked human in a group. This may be in a business setting or sometimes in other competitive areas, like sports. However, this is an extension by metaphor: humans do not have the same mating system as other social mammals. One reason is that the oestrous cycle in humans is different. This has the result that females may be sexually receptive at almost any time. Also, humans generally pair off, and alpha males do not have exclusive rights over all females in a group, except in rare circumstances.
Marshall Islands

The **Republic of the Marshall Islands** (RMI) is a Micronesian island nation in the western Pacific Ocean. As of 2018, about 58,000 people live there. The capital of Marshall Islands is Majuro. The official languages are Marshallese and English.

Roughly 10% of the population of the Marshall Islands can now be found in northwest Arkansas, U.S. Most live and work in the city of Springdale, a community of roughly 50,000. Each year, the Marshallese host a homecoming event so friends and relatives can get together to celebrate, stay in touch with politics at home, and spread their island culture. They meet at the Jones Center for Families in Springdale and have dancing, feasting, volleyball, and basketball. As a population, they are devoted to family and church and bring island dance and song to this corner of Arkansas.

## References
## Other websites
Vertebrate

]]

A **vertebrate** is an animal with a spinal cord surrounded by cartilage or bone. The word comes from vertebrae, the bones that make up the spine. Animals that are not vertebrates are called invertebrates. Vertebrates include birds, fish, amphibians, reptiles, and mammals. The parts of the vertebrate skeleton are:
#Braincase: A braincase or cranium protects the brain.
#Vertebrae: A series of short, stiff vertebrae are separated by joints. This internal backbone protects the spinal cord. The joints between the vertebrae let the backbone bend.
#Bones: support and protect the body's soft tissues and provides points for muscle attachment.
#Gill arches: Gill arches in the pharynx of fish and some amphibians support the gills. In the majority of vertebrates some of the arches have evolved into other organs, such as jaws.

Examples of vertebrates are mammals, birds, and fish. A few tens of thousands of species have been identified. The term "fish" is used to describe at least four different kinds of vertebrates.

## Distinctions 
Vertebrates dominate amongst the animals in virtually all environments. They include the largest animals in each main ecosystem, though not the largest living things (because that would include trees). They are the only animals which have an adaptive immune system. These two facts may be connected.

## Taxonomy and classification
* **Subphylum Vertebrata**
****Agnatha** (jawless vertebrates)
*** Myxini
*** Hyperoartia (lampreys)
** †Conodonta
** †Pteraspidomorphi
*** †Thelodonti
*** †Anaspida
*** †Galeaspida
*** †Pituriaspida
*** †Osteostraci
** ** Gnathostomata** (jawed vertebrates)
*** †Placodermi (Paleozoic armoured forms)
*** Chondrichthyes (cartilaginous fish)
*** †Acanthodii (Paleozoic "spiny sharks")
*** Osteichthyes (bony fish)
****Actinopterygii (ray-finned fish)
**** Sarcopterygii (lobe-finned fish)
**** Coelacanthimorpha (coelacanths)
**** Dipnoi (lungfish)
** **Tetrapoda** (four-limbed vertebrates)
*** Amphibia (amphibians)
*** Amniota (amniotic eggs)
**** Sauropsida (reptiles and birds)
***** Lepidosauria (lizards, snakes and tuatara)
***** Testudines (turtles)
***** Archosauria (archosaurs)
****** Crocodilia (crocodilians)
****** †Pterosauria (pterosaurs)
****** Dinosauria (dinosaurs)
******* Aves (birds)
**** Synapsida (mammal-like tetrapods)
***** Mammalia

## Related pages
* Invertebrate 
* Vertebrate brain

## References
## Other websites
* Tree of Life 
* Tunicates and not cephalochordates are the closest living relatives of vertebrates
Bag

school of 1962]]

A **bag** is a kind of soft container. It can hold or carry things. It may be made from cloth, leather, plastic, or paper. Many bags are disposable but some are made to use for a long time. A bag may have one or two handles or a shoulder strap. Bags come in different shapes and sizes depending on how they will be used. A small bag that can be carried with a single hand is sometimes called a handbag, purse, or pocketbook.  Children can suffocate, or stop breathing and die, when they put certain kinds of bags over their heads, due to having the supply of oxygen cut off.

## Other websites
Sapporo

is the capital city of Hokkaidō Prefecture in Japan. The port city is on the southwest part of the island of Hokkaidō and it is the island's largest city.

The city has a famous snow festival in winter, it has a growing population of about 1,800,000 .  Its area is . There are a lot of fish markets in Sapporo. A beer brand named "Sapporo" was named after this city. Ramen is a very popular food in Sapporo. The city has a subway system. Some famous landmarks are the Sapporo TV Tower, and the clock tower that is in the center of the city. There are several universities here, including Hokkaido University. The nearby airport is called New Chitose Airport.

## Events
*1972 - The Winter Olympic Games were held in Sapporo.

## Related pages
* Consadole Sapporo

## References
## Other websites
* City of Sapporo
* Sightseeing of Sapporo 
* Sightseeing of Sapporo
Hokkaidō Prefecture

is a special Japanese prefecture in Hokkaidō region on the island Hokkaidō.  It is the most northern prefecture of Japan.

Sapporo is the capital city of Hokkaido.

* **2008** (*Heisei 20*): The 34th G8 summit was held in Toyako.

## Geography
Hokkaidō is the 2nd largest island of Japan

## Shrines and Temples
*Hokkaidō jingū* was the chief Shinto shrine (*ichinomiya*) of Ezo, which was an ancient name for the Hokkaidō region.

## Related pages
* Provinces of Japan
* Prefectures of Japan
* List of regions of Japan
* List of islands of Japan
* Consadole Sapporo

## References
## Other websites 
* Murdoch's map of provinces, 1903
Fast

**Fast** can mean different things:

* Moving at a high speed
* **Fasting** -  when someone stops eating.
* Quick
Periodic table (metals and non-metals)

Color coding for atomic numbers:
* Elements numbered in blue are liquids at Standard Temperature and Pressure (STP);
* those in green are gases at STP;
* those in black are solid at STP;
* those in red are synthetic (all are predicted to be solid at STP).
* those in gray have not yet been discovered (they also have muted filled colors indicating the likely chemical series they would fall under).

## Related pages 
* Periodic table
Breakfast

**Breakfast** is the first meal of the day. It is usually eaten in the morning. The word comes from two other words; "break" ("end") and fast ("not eating for a long time").

Definition: [1463] from break (v.) + fast (n.). Cf. Fr. déjeuner "to breakfast," from L. dis-jejunare "to break the fast."

People around the world eat different things for breakfast:

* In the United States, people usually eat pancakes, waffles, toast, eggs or bagels for breakfast.
* In Canada, people usually eat maple cured bacon, fried potatoes, maple-infused beans, eggs, toast, pancakes and maple syrup or hot oatmeal for breakfast.

* In the United Kingdom a large breakfast was often, and still is sometimes, served. Usually this would be bread, tea, egg, bacon, ham, fruits, baked beans on toast and sometimes vegetables. This pattern of heavy eating has greatly changed in recent years. Most people do not do manual work nowadays.
* In France, people usually eat a very light meal; often bread and coffee with milk. Again, this depends on what kind of work is done (usually by the father of the household).
* In Asia, most people eat rice instead of bread. They also sometimes eat porridge.

## References 
## Related pages 
*Bacon and eggs
*Diet (nutrition)
Bible study

**Bible study** is intensive reading of the Bible.

For some Christians, study of the Bible is part of daily life. Many non-Christians also read the Bible, because it is an important piece of world literature.

In Europe before the 16th century, most people could not study the Bible.  Books were written only in Latin and Greek.  Only people who had learned to read those languages could study the Bible.   

At the time, the Roman Catholic Church did not allow people to translate the Bible into other languages, like Italian or English. Many people could not read and it took the lifetime of a monk, by himself, to translate the Bible.  

When the Reformation started in 16th-century Europe, the Bible was translated into several languages.  Many books were printed in these languages. People were then able to read the Bible in their own language.

## Related pages
* Biblical study, the academic study of the Bible
Medlar

The **medlar** is a tree and the name of the fruit of this tree. Its Latin name is *Crataegus germanica*, or "German medlar", but it is not from Germany. It grows in the Near East and South-Eastern Europe, and the Romans took it to Germany. Near the Caspian Sea, people grew the medlar about three thousand years ago. It came to Greece in about 700 BC and to Rome in about 200 BC. It was an important fruit plant in Roman and medieval times. But by 1600-1700, people started eating other fruits and not the medlar. Today people do not grow it very often.

The medlar needs warm summers and mild (not too cold) winters and likes to grow in sunny, dry places. In the best places, the plant can grow up to eight metres tall. The medlar is *deciduous*: it is not green all year. Usually, it is shorter than a tree. It lives between thirty and fifty years. Medlar leaves are dark green, maximum fifteen centimetres long and three centimetres wide. The plant has flowers in late spring. The flowers are white. The red-brown medlar fruits are similar to apples and grow to two to three centimetres. They are very hard and acidic, and we can only eat them after the cold weather makes them soft.

## Other websites
Hippocrates

**Hippocrates** (c. 460 – c. 370 BC) was a Greek doctor who is called the "father of medicine". He was the first person to teach that people got sick for scientific reasons. Previously, people believed that disease was caused by angry gods.

Many of Hippocrates' writings are still important to doctors. For example, patient confidentiality, meaning that doctors can only discuss a patient with the patient themselves. Another of his ideas is to never knowingly lead a patient to suffering or death. These kinds of ideas are part of medical ethics.

The Hippocratic Oath is named after him. This is a set of rules which doctors promise to obey. We don't exactly know what the original was, but this is an example of a modern *Hippocratic Oath:
*I do solemnly swear by all I hold most sacred:
* that I will be loyal to the profession of medicine and just to its members
* that I will lead my life and practice my art with virtue and honor
* that into whatsoever home I shall enter it shall be for the good of the sick and the well by the utmost of my power and that I will hold myself aloof from wrong and from corruption and from the tempting of others to vice
* that I will exercise my art solely for the benefit of my patients, the relief of suffering, the prevention of disease and promotion of health, and I will give no drug and perform no act for an immoral purpose
* that in the treatment of the sick, I will consider their well-being to be of a greater importance than their ability to compensate my services
* that what I may see or hear in the course of treatment or even outside the treatment in regard to the lives of persons which is not fitting to be spoken, I will keep inviolably secret
* that I will commit myself to a lifetime of continued learning of the art and science of medicine
* these things I do promise and in proportion as I am faithful to this oath, may happiness and good repute be ever mine, but should I trespass and violate this oath, may the reverse be my lot.

The oldest version we have is AD 275, and that is just fragments.

## References
Commensurability

**Commensurability** is a concept in the philosophy of science. Scientific theories are described as *commensurable* if one can compare them to find out which is more accurate. If there is  no way  one can compare them to determine which is more accurate, they are *incommensurable*.

Behind this is the idea that it is possible to see the world in multiple ways, and that there is not one fair method to see which way is right. Some think that scientific traditions (or *paradigms*) can be incommensurable: it is not really possible to say which one is right. This idea has been defended by Thomas Kuhn. He wrote: *when paradigms change, the world changes with them*. Paul Feyerabend was another philosopher who said that incommensurability was possible in scientific topics. He wrote that it is important to remember this, because it means that it is possible to say things that are not scientific, but also not wrong. These ideas were mainly aimed at Karl Popper and his ideas on falsification.

Two theories may not be comparable if one cannot find a way to compare them and decide which is right.

## In popular culture
The concept of incommensurability is dramatized in the 2006 movie *Idiocracy*, when U.S. Army scientist Joe Bauers attempts to explain before a full Cabinet meeting his theory that the nation's crops would be better irrigated with water rather than with a sports drink.

## References
Harvest

image]]
To **harvest** means to collect what has been planted and  in the ground. It is usually done by farmers. They can do this by picking crops. Crop failure (also known as harvest failure) is a loss or reduced crop yield due to plants being damaged, killed, or destroyed. Sometimes it brings famine.

"Harvest" can also mean to collect other things than plants such as cultivated bivalves including oysters, scallops, and other animals.
ELISPOT

**ELISPOT** stands for "Enzyme-Linked Immunosorbent Spot Assay".  It is a laboratory technique for detecting cells that make (or "secrete") various substances.  These substances include specific types of cytokines or antibodies.  The ELISPOT method is typically used with blood cells, and is a helpful tool in studying the human immune system and various treatments for disease (e.g. vaccines).

In the ELISPOT technique, tiny wells are used to contain the cells, with a variety of other substances.  The substances cause colored spots to form near the cells that secrete the substances in question. These spots can then be counted manually (using a microscope, for example) or automatically using specialized equipment with computer vision capabilities.

The ELISPOT technique is very sensitive, and can detect even a single substance-producing cell. It is also very versatile, since it can be tailored to detect a wide variety of very specific secretions.

## Other websites 
*A flash animation of the ELISpot procedure 
*An animated illustration of the ELISPOT process
*Examples of spot patterns formed by the ELISPOT technique
Billion

**Billion** is a name for a large number. There are two different meanings for the term:
* 1,000,000,000 (, one thousand million) is the short scale definition. It is used in both British and American English. The short scale has been used in the United Kingdom since 1974. Its prefix is “giga-“.
* 1,000,000,000,000 (, one million million) is the long scale definition. It was formerly used in the United Kingdom. It is currently in some other countries. When “billion” has this meaning, the word “milliard” can be used for “thousand million”.

Some examples of billion meaning thousand million:
* Over 1.3 billion people live in India.
* The total land area of Russia is 1.71 billion hectares.
* Billionaires are very rich people. Their wealth is in the billions of dollars, euros or pounds sterling.
* The Age of the Earth is about 4.5 billion years.
* One billion seconds is about 31.5 years.
* The distance to the planet Saturn from the Sun varies from 1.4 billion km to 1.5 billion km.

**Billion** may also refer to:
* *Billions* (TV series), a Showtime series
* *Billions* (movie), a 1920 silent comedy
* Billion (company), a Taiwanese modem manufacturer
* Jack Billion (born 1939), 2006 Democratic Party candidate for governor of South Dakota
* *Mr. Billion*, a 1977 movie by Jonathan Kaplan
* "Billions" (song), a song on Russell Dickerson's album *Yours*
Johannesburg

.]]

**Johannesburg** is the  largest city in South Africa. It is the capital of the Gauteng Province. It was founded on October 4, 1886 and has the JSE Securities Exchange, which is the largest stock exchange in Africa.

Johannesburg houses the tallest office block in Africa, the Carlton Centre (50 stories) and the tallest tower, the Hillbrow Tower (270 metres, or 90 stories).  The city is nicknamed Egoli or Jozi, which means "*place of gold*", for the large gold deposit at Witwatersrand.   

 The Johannesburg Zoo was established in 1904, and historically, it has been owned and run by the city of Johannesburg. It houses the only two polar bears in Africa. Johannesburg is not seen as a tourist centre in South Africa, but rather as a commercial centre.

Johannesburg has a subtropical highland climate (Cwb in the Köppen climate classification). Snow is a very rare event. It only snows in Johannesburg once or twice in a century.

Nelson Mandela died there on 5 December 2013, aged 95. He was also given the "Freedom of the City" award.  In 2023, a fire started in the town. The fire killed more than 70 people and became one of the deadliest fires in the history of South Africa.

## References
List of biochemistry topics

This is a list of all the articles related to biochemistry.

__NOTOC__

## A 
abiogenesis - adenine - adenosine diphosphate (ADP) - adenosine triphosphate (ATP) - albumin - allotrope - alpha helix - amino acid - amylase - antibiotic - antibody - antigen -

## B 
B vitamin complex - base pair - bilirubin - benzene - biochemistry - bioluminescence - blood - blood type

## C 
carbohydrate - carbon dioxide - catabolism - cell - cell membrane - cellobiose - cellular respiration - cellulose - chemoautotroph - chloroplast - choline - chromatography - citric acid - coenzyme A - cytoplasm - cytokine - cytosine - cytosol -

## D 
deoxyribose - disaccharide - DNA - DNA replication -

## E 
ELISA - ELISPOT - energy level - enkephalin - enzyme - epinephrine - erythropoietin -

## F 
fat - formaldehyde -

## G 
gel electrophoresis - glycolysis - glycoprotein -  granzyme - guanine -

## H 
hemoglobin - hormone - hydrocarbon - hydrogen bond - hydrolysis -

## I 
immunoglobulin - immunology - insulin - intermolecular force - ion channel - ionic bond - isomer -

## K 
keratin - kinetic energy - Krebs cycle -

## L 
Le Chatelier's principle - light-dependent reactions - light-independent reactions - Link reaction - lipid -

## M 
macromolecule - membrane protein - metabolism - microbiology - molecular biology - molecule - monosaccharide -

## N 
NADPH - neurotransmitter - niacin - nicotinamide adenine dinucleotide phosphate - Nobel Prize in Chemistry - nucleic acid - nucleobase - nucleotide - nutrient - nutrition -

## O 
organic chemistry - organic compound - osmosis - oxidation -

## P 
peptide - pesticide - pH - photosynthesis -  physiology - polymer - polysaccharide - potential energy - prion - protein - protein biosynthesis -

## R 
redox - respiration (physiology) - riboflavin - ribose - ribosome - RNA -

## S 
saturated fat - scientific notation - sequence analysis - signal transduction -  solvation - starch - substrate (biochemistry) - sugar - synapse

## T 
T cell - thymine - toxin - trans fat - transcription (genetics) - translation (genetics) -

## U 
unsaturated fat - uracil -

## V 
vaccine - virus - vitamin - Vitamin A - Vitamin C - Vitamin D - Vitamin E - Vitamin K -

## Y 
yeast -
Author

An **author** is a person who makes an original piece of work. Most people use author to mean writer. While a writer is a type of author, authors often do more than write. Anyone who creates something original is an author. These could be written items such as books, stories, or poems. This could also be other types of art, such as sculpture or music. Any type of work can be made by an author.

## *Writer* and *author* 
The term author is commonly used to refer to a person who writes as a profession. It is also believed by many that the term is used for writers who are  and who have had their works published. These explanations are common with people who work with those who write professionally.

An author does not always have to be a writer. If a person  a letter to a secretary, then the secretary is a writer, but the person who dictated the letter is the author.

## Examples 
Other examples of someone being called an *author*:
* In copyright law, the author is the first owner of copyright. These laws also apply to other works of art, such as pictures or music.
* In biology, the first person to write an article that gives a name to and describes a type of living thing is the author of that name.
* Someone who writes music may be called the author of that piece of music. Another name for an author of music is a composer.

## French usage 
When talking about movies, the French word for author, *auteur*, is often used about someone who has been both the writer and director of a movie.

## Related pages 
* Writer
* Journalist
* Genre of literature

## References 
## Other websites 
* Networks of scientific papers
Pedipalp

with pedipalps in green]]

**Pedipalps** are the two appendages on the front of a spider's head. Other arachnids, and chelicerates that are not arachnids also have pedipalps. Some spiders seem to have ten legs and not eight, because these pedipalps look like an extra pair of legs. The pedipalps are used rather like arms.  Spiders often use them to hold insects (for example crickets) for them to eat.

Male spiders also use pedipalps for mating.  The male spiders make some silk, put sperm onto the silk, and then put their pedipalps into the sperm.  The pedipalps then hold the sperm, and the spider can use it to mate with a female by putting them inside her epigynum.

## Diversity of pedipalps 
The pedipalps of all chelicerates vary: Ricinulei, Thelyphonida, Amblypygi, some Opiliones, Schizomida, scorpions and pseudoscorpions all have theirs as pincers, with the Amblypygi's being their entire pedipalps shaped like mantids. The Palpigradi's pedipalps have some of the strangest roles of arachnids as they use theirs for locomotion. The pedipalps of Solifugae act as antennae.

## Other websites 
*Close-up view of pedipalps on a large spider
ELISA

The **ELISA** method (**Enzyme Linked Immuno-Sorbent Assay**) is a technique used in biochemistry to determine if a certain substance--such as a specific cytokine or antigen--is present within a sample. It is sometimes abbreviated as "EIA."

This technique uses special antibodies that attach themselves to the substance. These antibodies generate a specific color. The amount of color indicates the amount of substance present. (Sometimes, the substance must be viewed under ultraviolet light for the antibodies to generate this color.)

Another set of antibodies are used to "capture" the substance. These antibodies adhere to both the substance and the testing container, thus holding the substance in place.

A more sophisticated and sensitive technique, the ELISPOT method, was derived from the ELISA techique.

## Other websites 
* An animated illustration of an ELISA assay
* Image of a microtiter plate, such as is commonly used in ELISA tests
David Hume

. The image is in the Scottish National Portrait Gallery]]

**David Hume** (7 May 1711 When he was still alive, people thought of him as a historian. He wrote a series of large books called *The History of England*. But today, people think of Hume as an important philosopher.
## Works
In his books on philosophy, Hume said that many of our beliefs do not come from . Instead, they come from our instincts or feelings. For example, reason does not tell us that one thing causes another. Instead, we see one thing and then we see another, and we *feel* a link between the two. Similarly, reason does not tell us that someone is a good person. Instead, we see that the person is kind and friendly, and we *feel* a special moral feeling. Because Hume thought that these beliefs do not come from reason, people call him a "skeptical" or "anti-rationalist" philosopher.

Hume is famous for his 'Induction Fallacy'. This draws attention to a common mistake people make. People see something, and make claims that what they see will always be as they see it. For example, people see only white swans and claim that all swans are white. This is 'fallacious' or mistaken, because it is always possible that they then will see a black swan.

Hume was also skeptical about religion. Today, Hume's books are very important to philosophers who are interested in religion.
## Influence
Today's philosophers sometimes use the term 'Hume's fork' to refer to Hume calling everything we can think about either a relation of ideas (things like mathematics, that must be true) or a matter of fact (like science, where we have to look at things to tell whether or not they are true).

Another philosopher, Immanuel Kant, read some of Hume's books and changed his mind about some important things. Kant said Hume had made him wake up from a sleeping dogmatism, the traditional metaphysics.

## Books
Here are Hume's most important books:

* *A Treatise of Human Nature: Being an Attempt to introduce the experimental Method of Reasoning into Moral Subjects.* (1739-40)
:In this large book, Hume talks about the human mind and tries to figure out how it works. He talks about knowledge, cause and effect, emotions, right and wrong, and many other things.

* *An Enquiry Concerning Human Understanding* (1748) 
:In this small book, Hume talks about many of the same things from the Treatise, like knowledge and cause and effect. He tried to make this book easy to read.

* *An Enquiry Concerning the Principles of Morals* (1751)
:This is another small book, and again, Hume tried to make it easy to read. The book is about right and wrong.

* *Dialogues Concerning Natural Religion* (after Hume died)
:In this book, Hume has three characters who argue with each other about God.
## References
Ionic compound

structure of sodium chloride, NaCl, a typical ionic compound. The purple spheres are sodium cations, Na+, and the green spheres are chloride anions, Cl−.]]
In chemistry, an **ionic compound** is a compound made of ions. They have strong ionic bonds between particles. Lots of energy (heat) is required to break the bond apart, resulting in high melting and boiling points. The ions join because they have different charges. Compounds of metals and non-metals are usually ionic. They are made when two or more atoms come close together and an electron goes from one atom to the other atom. The electron does this because both atoms want a full outer shell, similar to those of the noble gases.

**Note 1**: carbon and silicon in Group 4 usually form covalent bonds by sharing electrons.

**Note 2**: the elements in Group 0 do not react with other elements to form ions

## Physical properties
Brush

A **brush** is a tool with bristles or wires or other filaments sticking out. There are many kinds. Most brushes have a long part at one end to hold (the handle), on the other end from the head that carries the bristles or filaments. We use brushes for cleaning, making hair look good, painting, and other purposes.

## Brushes for cleaning
Many kinds of brushes are made for cleaning, for example toothbrushes or brushes for cleaning floors.

## Paint brushes
We use paint brushes for putting ink or paint on paper. If a brush is dipped 1/3 to 1/4 of its length into a can of paint, a good brush will ideally pick up the perfect amount of paint and spread it on a surface in a film that is smooth and uniform and absent of any drips, dips, or brush marks. Paint brushes typically come in two forms, synthetic, and natural. Synthetic brushes are usually made from products such as nylon, while natural refers to bristles from an animal source. Computer graphics uses digital paintbrushes for making pictures.

Paint brushes can have three shapes:
* Round: The long, close-together bristles of these brushes mean they can hold more paint. This is why many artists like them for painting large things and for color washes.
* Flat: These are good for spreading paint.
* -shaped: These mix paint well.

### Brush care 
* Clean paint from brushes after you use them. This is very important for oil and acrylic paint because when the paint is dry, taking it off can break the brush.
* Never leave brushes in water (etc.) with the bristle end down. This is because the bristles can change shape.

### Sizes and materials 
We can buy brushes in different sizes and materials. Here are some sorts.

#### Decorators' brushes 
The sizes of brushes used for painting and decorating (changing the colour or look of a room) are usually in millimeters or inches. This shows how wide the head is.

Here are some sizes:

* 1/8", 1/4", 3/8", 1/2", 5/8", 3/4", 7/8", 1", 1", 1½", 2", 2", 3", 3", 4".
* 10&nbsp;mm, 20&nbsp;mm, 30&nbsp;mm, 40&nbsp;mm, 50&nbsp;mm, 60&nbsp;mm, 70&nbsp;mm, 80&nbsp;mm, 90&nbsp;mm, 100&nbsp;mm.

We can buy brushes with natural or synthetic (man-made) bristles. Handles (the part of the brush we hold) may be wood or plastic.

#### Artists' brushes 
Artists' brushes usually have sizes with numbers, but there is no standard.

From smallest to largest, the sizes are:

* 7/0 *(also * 0000000*)*, 6/0, 5/0, 4/0, 000, 00, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 20, 22, 24, 25, 26, 28, 30.

We use sizes *000* to *20* most often.

Bristles may be natural—either soft hair or hog (pig) bristle—or synthetic (man-made).

Artists' brush handles (the part of the brush we hold) are often wooden, but the cheapest brushes may have plastic handles. Many cheap handles are made of unfinished wood; better quality handles are of finished wood.

## References
Starch

, a pancake made from cassava and starch]]
**Starch** is a complex carbohydrate. It is made of many glucose units joined by chemical bonds. This polysaccharide is produced by most green plants as an energy store. It is the most common carbohydrate in human diets. Pasta, potatoes, bread, and other starchy foods are made out of carbohydrates. 

## Starch in every day activities 
### Starch in food 
Some good food sources of starch are cereals, bread, potatoes, grains, peas, and beans. Starch is also used for thickening sauces in cooking and thickening cold foods during a preheat. Starch is a white powder that is tasteless and odourless. Corn starch or cornflour is known as a popular kind of starch made from corn.

Foods with a lot of starch produce more energy than other foods. However, if this energy is not used, it is turned into fat by the liver through de novo lipogenesis.

### Laundry starch 
There are also different kinds of starch, like laundry starch, which gives clothing a smooth and crisp feel. Sweat and dirt from a person’s wrist and neck will stick to the starch on the clothes, not to the fibers of the clothes, and will wash away along with the starch. Then, after each laundry load, the starch can be used again.

## Other facts 
Starch glues are used in wood, cotton, and bonding of paper. Animals and humans have amylase, so they can digest starch.
Starch was used in Europe in the 16th and 17th centuries to stiffen the collars and ruffs of the fine linen which surrounded the neck. Starch also requires heat to thicken. The actual temperature depends on the type of starch.
Thomas Hobbes

**Thomas Hobbes** (5 April 1588 – 4 December 1679) was a philosopher from England. His most famous book is *Leviathan* (1651).
## Writings
Hobbes was a political philosopher. He wrote mainly about government and law. He tried to show that the best societies have one authority. This authority had virtually all power. All individuals living in society under the authority must give up some rights and freedoms, but in exchange they received protection. Hobbes didn't believe in any "separation of powers" among different people. He thought the ruling authority must control everything: , military, judicial, and ecclesiastical.

## Studies
Hobbes believed that human nature makes people selfish and willing to hurt each other if they think it will help their own self. He believed nature makes all humans basically equal because we can all kill each other— for example, a small child can kill a strong man if he catches the man asleep. Imagine what things would be like without a government. It would be terrible—a "state of war". There would not be enough stuff for everyone, and people would disagree about who got what. Some people would fight each other, and everyone else would be very worried about their own safety. No one would be able to trust anyone else or make plans for the future. Life would be "solitary, poor, nasty, brutish, and short" (people would be alone, poor, mean, and would not live for long). Next, Hobbes argues that it would be a good idea for everyone to stop fighting and choose a Sovereign which could be one man or an assembly of men. Everyone should agree to obey the Sovereign, and give him all power of coercion or force of restraint under law. Once the Sovereign is in place, everyone has to obey him, even those who disagree with him. This is because everyone already agreed to obey him no matter what. Hobbes says it's better to be mostly safe under an all-powerful Sovereign, than to be in a state of war.

Hobbes wanted his argument to be like math, with each step leading to the next. However, many people disagreed with his argument. Some said that Hobbes was in favor of rebellion, because he said that people were naturally equal. Others said that humans are not as selfish as Hobbes thought. Today, most people do not like the idea of an all-powerful government. Nevertheless, Hobbes's argument was a very important one, and philosophers who are interested in government or political theory still study Hobbes's books very carefully.

## References
Nicomachus

**Nicomachos** or **Nicomachus** is a Greek name. It can mean:
*Nicomachus of Gerasa, an ancient mathematician

*Nicomachus, the father of Aristotle and court physician (doctor) to King Amyntas III of Macedon. Nicomachus died when Aristotle was about 10. Nicomachus wanted Aristotle to follow in his footsteps. But Aristotle did not become a doctor but a philosopher.
This is a unique name (not in the top 1000 newborn names in the US in 2021).

## References
Logo

's logo]]
]]
]]

A **logo** is a picture or drawing that is used by a person, group, or company to mark who they are. A **wordmark**, or 'logotype', is a logo made entirely of a word or words. It is usually the name of a product or organisation.

A company or group can use a 'logo' on the things that they make, like on the things they sell, on letters, and in advertisements. When a person sees the logo picture, that person knows that the thing they see the logo on came from that company.

Logos can have letters and words in them. Many logos have the name of the company or group in them.

Most logos are very simple drawings with only a small number of colors. Some logos are only in black and white.

In many countries, companies and groups should tell their country's government about the logo they are using. If they do this, the government can help stop a different company or group from using the same logo, so that every one can be sure that the logo is only used by the people who used it first. This is sometimes called a 'trade mark'.

Logos are not used only by companies. Many schools have logos. Some cities have logos. Clubs can have logos. Even people can have their own logos if they want. The heraldic badge is probably the oldest form of logo in the world.

## Related pages 
*Logogram

## References
Picture

the environment with a mobile phone camera. The display of the mobile phone shows a live display of the image.]]
A **picture**, also called an **image**, is a group of coloured points on a flat surface that looks the same as something else. For example, a picture can look the same as an  or a person. Pictures can also be drawings, paintings or photographs. People who make such pictures are called artists, photographers or painters.  Pictures are very helpful.  Sometimes people say pictures are worth a thousand words.  Pictures and diagrams can be used to explain how to do things, and thus a picture is a kind of tool. A moment captured in an image.

An **image** is something that can be seen, but it is not physically there.  It can be a photograph, a painting, or a picture on a television or computer screen.  A lens can make an image of an object appear somewhere else.  Cameras use this to make the image that becomes a photograph.

## Making Pictures
Most pictures today are 'photographs'. Photographs are made with cameras. A camera makes a picture that looks very real.

When there were no cameras, people made pictures by using paint, brushes, pencils, crayons, pens, and other things that people can write or draw with. Pictures made with paint and brush are called 'paintings'. Before cameras, some artists were able to make very real looking pictures with just paint. Sometimes pictures made with pencil or pen are called 'sketches', if they are made quickly and only look a little bit like the real thing.

Usually pictures are put on paper. Pictures made with paint are usually put on a strong, rough fabric called 'canvas'. Sometimes pictures can be put on walls or other things, even glass.
 made from radio waves (red) and X-rays (blue)]]
Some places, such as churches have pictures on windows made out of colored pieces of glass. These are called *stained glass*.

## Special types of Pictures 
If people take a lot of pictures, and show them one at a time, very fast, they can make a picture that looks like it is moving.  This is called a "moving picture", or a movie.  A television shows people a moving picture by using light. 

A slide show is a series of pictures arranged to tell a story, for example to illustrate a narrative.  

A projector shines light from a light bulb through a kind of transparent picture.  When light shines through this kind of picture onto a screen or another flat place, the picture can be seen on that flat place.  This is often used to show movies and slide shows to an audience.

Some people make pictures that do not look flat, by taking two regular flat pictures at the same time. People have to move their eyes in a special way or use a stereoscope so they can see both pictures together.  When they look at the pictures using their binocular vision correctly, the picture does not look flat.  This is called '3D' or 'three dimensional'.

Cutaway pictures show what is inside of something, that cannot actually be seen.
Candle

A **candle** is a stick made of wax with a string (a thin piece of rope) straight in the middle. If someone puts the string on fire, the flame burns slowly but for a long time.

Fire can burn string very fast. But in a candle, the string does not burn fast, because the fire melts the wax instead. The wax sometimes drips down the side of the candle. When the melted wax is far from the flame, it gets hard again, and can be used again in a new candle. 
 
The flame is very hot, since it is a very small, real fire. The light blue part of the flame can be as hot as . It can still burn people and things. If the fire spreads, it can grow into a very big fire and even burn down a house or building. 

If the flame is kept on the candle long enough, the candle will slowly get shorter and shorter until it is gone. The fire on a candle can be put out by blowing air on it. There is also a special tool called a "candle snuffer" that covers the fire with a small metal cup and puts it out. Today, candle snuffers are usually only used in churches or in places where candles are up very high. Stopping the fire stops the candle from burning until it is all gone.

Before light bulbs, candles were used so people could see at night. Some people still use candles today when electricity is down, or because they like the little amount of light that candles make. Some people also like candles because they look nice, or because they smell nice. A special kind of plant called "citronella" can be infused into the candle to help keep bugs away.

## Related pages
* Lantern
* Electric light
* Advent

## References