open-index/open-wikipedia-markdown huggingface dataset:
Social sciences

The **social sciences** are a group of academic disciplines that study human aspects of the world. Social Sciences includes anthropology, archaeology, economics, geography, political science, psychology, social philosophy and sociology. They are different from the arts and humanities, and application of the scientific method is important. Most of the social sciences require doing a lot of research, such as making surveys. Such research is called "social research". Some subjects, such as history, are sometimes social sciences and sometimes humanities. 

The term "social sciences" has been used for over 200 years and mostly originates from a thinker named Auguste Comte. Many of the fields of social science have come about since then. In America, much of the thought and practice of social science came from the University of Chicago and other universities.

## References 
## Other websites 
* Social Science Virtual Library 
* UC Berkeley Experimental Social Science Laboratory
* Social Science Information Gateway  (UK)
* History of Social Science 
* On the Social Sciences Critical Essays
* praxeology as the method of the social sciences
* in defense of extreme apriorism
Statistical survey

**Statistical surveys** are  of information about items in a population. 

Surveys can be grouped into numerical and categorical types. A numerical survey is to get numbers as replies. For example:

How many minutes, on average, do you spend eating breakfast?

This survey question is used to generate numbers in minutes. An example of a categorical question is:

What is your favorite color?

The categories for this would be yellow, green, purple, etc... which are not numbers.

Surveys of human populations and institutions are common in political polling and government, health, social science and marketing research. A survey may concentrate on opinions or factual information depending on its purpose.

## Other websites 
*American Association for Public Opinion Research (AAPOR)
*How to design a web-based statistical survey online. 
*Ajeebo: Web based survey software tools directory 
*Conducting Web-Based Surveys 
*Free resources for methods in social research  has links to resources for surveys and sampling.
*Online Survey Best Practice 
*Short Courses in Survey Methodology, sponsored by the Joint Program in Survey Methodology (JPSM) - University of Maryland-College Park and University of Michigan-Ann Arbor 
*The EvaluationWiki  - The mission of EvaluationWiki is to make freely available a compendium of up-to-date information and resources to everyone involved in the science and practice of evaluation. The EvaluationWiki is presented by the non-profit Evaluation Resource Institute .
Nuclear proliferation

represented by color.

]]

**Nuclear proliferation** is when a country starts making nuclear objects. On the right is a map showing who has nuclear reactors and weapons, and who could have them. When a country starts making nuclear weapons, they become a nuclear power.

## Dual use technology
Dual use technology means the possibility of military use of civilian nuclear technology for generating electricity. Many technologies and materials associated with the creation of a nuclear electricity program have a dual-use capability. These items can be used to make nuclear weapons if a country chooses to do so. When this happens a nuclear electricity program can lead to making atomic bombs. The crisis over Iran’s nuclear activities is an example.

## References
Arts

**The arts** are a large part of culture, and the word means much more than "*art*". **The arts** include visual arts, literary arts (i.e. books and other writings) and performing arts (i.e. music, dance, drama). 

Sometimes, in universities, it is shorthand for a wider group of subjects which are properly called the humanities. These include philosophy, theology, literature, languages, and history as well.  

"The arts" are usually contrasted with "The sciences".

## Visual arts 
Visual arts consist of any art that can be seen. This form of art doesn't change once it has been made.
### Painting 
Painting is an art that uses pigments to create images. The oldest painting was made on a cave wall, in prehistorical times by a Neanderthal.
### Sculpting 
Sculpting is an art that uses height, width, and depth. You can create a sculpture by carving or shaping things such as rock, metal, or wood.
### Architecture 
Architecture is the art and science behind building and sculpture design. Architecture as an art involves making something look beautiful and appealing to others.

## Performing arts 
Performing arts are those that occur when people show others their artistic skills. These include dancing and singing.

## Literary arts 
Literary arts are those that occur as words. Most are written down, but in the ancient past, some long poems were only told in speech for hundreds of years before finally being written down!

## Conceptual art 
Conceptual art is art in which the idea is more important than the actual beauty of the object.

## Other websites 
* Dictionary of the history of ideas — Classification of the arts 
* Open Directory — Arts 
* National Endowment for the Arts — USA 
* Arts Council — England
* Americans for the Arts
* ArtsJournal — Daily Arts News
* Arts — New York Times
* Arts — The Times 
*Association of Hispanic Arts (AHA) 
* History of Art: From Paleolithic Age to Contemporary Art
Minor League Baseball

**Minor League Baseball** is a level of professional baseball in North America. It is made up a many different teams which play in many leagues and levels of skill. Minor league teams are used by Major League Baseball (MLB) teams to have a place to put their players who they do not feel are skilled enough to play in the major leagues yet. They are also used to help injured major league players get ready to play in MLB again. These partnerships between major and minor league teams are called affiliations. Minor league teams generally play in cities that are too small for major league teams. City size usually increases with league level.

There are five different classifications (skill levels) in the minor leagues, these classes are (in order from lowest to highest):
* Complex League (or Rookie League)
* Single-A
* High-A
* Double-A (or AA)
* Triple-A (or AAA)

When a normal player is first drafted or signed by an MLB team, he is usually placed on a Complex League team, however more advanced players may start higher. If a player plays good in his league, he can be promoted or "called up" to the next league. If a player does not play well, he may be sent back down or removed from the team. This continues until a player gets to the major leagues, although most players never make it that far. This way, players are able to get better at baseball before having to play against tougher opponents. Almost all players in MLB had to play in the minor leagues first to become good enough to play in the major leagues. Most players spend four to five years in the minors before making it to MLB. However, skilled players can be called up earlier, while some may take more than 10 years to reach the majors.

Sometimes, major league players who are have been hurt will play a few games in the minor leagues before playing in the major leagues again, in order to see if they feel healthy enough to start playing again.

There are other professional baseball leagues that are not affiliated with major league teams. These are known as "Independent Leagues". In these leagues, players do not go to higher or lower levels of ability. Players on these teams are usually those not drafted by an MLB team. They may also be players who played in major or minor leagues and are trying to get back. Major league teams may hire these independent players to play for their teams.

## Leagues
**Triple-A**
* International League
* Pacific Coast League

**Double-A**
* Eastern League
* Southern League
* Texas League

**High-A**
* Midwest League
* Northwest League
* South Atlantic League

**Single-A** 
* California League
* Carolina League
* Florida State League

**Rookie**
* Arizona Complex League
* Florida Complex League
* Dominican Summer League

**Off-season leagues**
* Arizona Fall League

**Showcase league**
* MLB Draft League

**Partner leagues**
* American Association 
* Atlantic League 
* Frontier League 
* Pioneer League

## References
## Other websites
*Minor League Baseball's official website
François Bourdoncle

**François Bourdoncle** (born 1964) is founder and CEO of the search engine company Exalead.

## Literature
* *Semantic Analysis of Interval Congruences*, 1993, , Author François Bourdoncle, Springer-Verlag, London, UK.

## Other websites 
* www.exalead.com/Francois.Bourdoncle
Exalead

**Exalead** [eg'zæli:d] is a company in Paris and founded in 2000 by Francois Bourdoncle. Its name comes from the association between
* the prefix *exa* which means 1018 (used as a generic term for size, to imply large coverage of pages)
* and the verb lead (as the customer is led through the search options)

Exalead tries to integrate research functions in one piece of software, combining Internet, desktop and enterprise functionality.

Exalead employs approximately 60 people in 3 countries (Paris in France, Milano in Italy and New York and San Francisco in the United States of America).
Humanities

The **humanities** include languages, literature, music, philosophy, politics, history, media, the classics, religion, and the visual and performing arts. Additional subjects sometimes included in the humanities are anthropology, area studies, communications and cultural studies, although these are often regarded as social sciences. It was popular in the Renaissance ages.

The arts are usually considered as part of the humanities. These include visual arts such as painting and sculpture, as well as performing arts such as theatre and dance, and literature. Other humanities such as language are sometimes considered to be part of the arts, for example as the *language arts*.

The humanities study the human condition and mostly use methods that are analytic, critical, or speculative and not as empirical as natural and social sciences.

## Related pages 
* Human nature
* Human science
* Liberal arts
* Trivium

## Other websites 
* The Humanities Association - UK
* UK Humanities Hub 
* Australian Humanities Review 
* Australian Academy of the Humanities
* Virginia Foundation for the Humanities
* Mass Humanities / Massachusetts Foundation for the Humanities

## References
Shawarma

**Shawarma** (; in ) is a meat sandwich eaten by people of the Arab world and the Middle East. It is served in round Arabic bread with meat and vegetables, with some spice or sauce of choice in it. Normally, the meat can either be lamb, beef, turkey, or chicken. Shawarma can also be spelled **chawarma**, **shwarma**, **shawerma**, or **shoarmais**.

It was first introduced by people from Turkey. They call it *çevirme*, which means "turning", because the meat can be turned around in the oven, but the Arabs changed its recipe from the Turkish Doner kebab.
Amateur radio

**Amateur radio** is a hobby for people who like to talk using radio transmitters. Many people enjoy using amateur radio to talk to other amateur radio hobbyists in other countries. Amateur radio hobbyists also use their radio transmitters to get help in emergencies. Amateur radio is often called *ham radio*. Many people use their  radios for . People who use Amateur radio are often called *amateur radio operators*, *hams* or *amateurs*.

During a disaster or emergency, amateur radio can be used to get help. When telephones do not work, it may be the only way to communicate. Some radio hobbyists volunteer to listen to emergency band frequencies in case there are distress calls. If the volunteers hear a distress call, they notify the appropriate authorities (for example the police or the Coast Guard).

## License
People must have a license to use Amateur radio legally. In most countries users must pass a test to get a license. In some countries there is more than one license grade. In some countries, people can use Amateur radio if they have a license from their home country.

There are many clubs for Amateur radio in many countries. These clubs do many things as a group and help people get their Amateur radio license.

## Talking
Amateur radio operators talk to each other in many ways. Some people talk with their voice, others use computers, television, or Morse code. They use many ways to get their signals to others. Most use shortwave radio signals that bounce off the sky. Some bounce off the moon or a satellite. Amateur radio operators have many ways to talk using the radio. Amateur radio satellites are called OSCAR's - Orbital Satellites Carrying Amateur Radio. Hams can also talk to astronauts and cosmonauts aboard the International Space Station (ISS).

## Fun
There are many ways to have fun with amateur radio. There are many games and contests. Amateur radio operators try to talk with as many others as possible. They then mail each other postcards called *QSL cards* to confirm the contact. Contesters may try to see how far they can talk, or to how many different people they can talk.

Some hide a transmitter which sends out a signal and others try to find it using receivers. This is called *radio direction finding* or *fox hunting*. Sometimes the event is done with cars, or as a foot race.

## In India
Amateur radio is practised by over 15,000 licensed users in India. The first amateur radio operator was licensed in 1921. By the mid-1930s, there were around 20 amateur radio operators in India. Amateur radio operators have played an important part in the Indian independence movement with the setting up of pro-independence radio stations in the 1940s.
Merchant

**Merchants** are people that deal with trade. That means they buy and sell goods that they do not produce themselves, in order to get profit.

Merchants can be two types:

# A **wholesale merchant** works between producer and retail merchant. Some wholesale merchants only organise the movement of goods rather than move the goods themselves.
# A **retail merchant** sells goods to consumers (including businesses), commonly known as retailers. A shop owner is a retail merchant.

In the US, "merchant" is  any person while engaged in a business or profession or a seller who deals regularly in the type of goods sold.  Under the common law in the United States, merchants are held to a higher standard in the selling of products than those who are not engaged in the sale of goods as a profession. For example, when a merchant sells something, he or she is expected to give a warranty, guaranteeing that the product is fit to be sold, even if there is nothing in writing to this effect.

## Related pages
* capitalism
Blue box

A **blue box** is a device that someone could use to make free telephone calls. It worked by playing back the same sounds that the telephone company employees used to program their .

The most famous person to use a blue box was John Draper, who went by the name Captain Crunch. Draper taught Steve Wozniak how to build them. Wozniak and Steve Jobs sold blue boxes to fellow students at the University of California, Berkeley. One time, Wozniak used a blue box to call the Pope.

## Related pages
* Red box
Red box

A **red box** is a device that people used illegally in the 20th century to make free telephone calls at a payphone. It worked by playing back the same sounds that the payphone sends to the phone company when coins are put into it.

## Related pages
*Blue box

## Other websites 
* "Frequently Asked Questions About Red Boxing" by Mr. Sandman
* All about the Red Box and related devices 
* Red Boxing For Dummies
Coconut palm

]]

The **coconut** is a palm tree in the family Arecaceae (palm family). It is a large palm, growing to 30 m tall. It has leaves that are 4–6 m long. The term *coconut* refers to the fruit of the coconut palm.

There are many coconut palms on the coasts of Indonesia, India, America, Bangladesh and Tanzania. People of this area use coconut milk in cooking. Women use coconut oil as oil for their hair. The coconut's shell is relatively hard, but can be broken. Because its shell is hard, it can be used as an ingredient to make craftworks. 

Coconut milk is also used in many drinks. Coconut oil is often in food and soaps. People in Sri Lanka use coconut flowers for wedding celebrations. In the Maldives it is the National tree.

The coconut is not actually a nut, but is in fact a drupe. Coconuts grow in tropical countries. The flesh of a coconut is white and can be eaten raw or used in cooking. It is used in many of the foods we eat for flavour. It is native to tropical areas.

## Seed dispersal 
Coconuts float on water and can float to another island and germinate there. It has often been noted that coconuts can travel up to 110 days, or 3000 miles, by sea and are still able to germinate.
Constituency

A **constituent** is a voting member of a community or organization and has the power to appoint or elect. A **constituency** (also called an **electoral district**, **riding**, or **ward**) is all of the constituents of a representative. Constituents also have the power to remove their representative from the position to which they have appointed him or her. All of the constituents who are registered to vote are called the *electorate*.

In the United Kingdom, a parliamentary constituency is a district that elects a member of parliament. It is sometimes called a *Parliamentary seat* or a *Division*. Constituencies for local government elections are called either *Wards* or *electoral divisions*.

As of 2020, there are 650 House of Commons constituencies in the UK:
* List of Parliamentary constituencies in the United Kingdom
* MPs elected in the UK general election, 2005 lists the constituencies after that election.

Northern Ireland has 18 constituencies, each of which elect six MLAs to  the Northern Ireland Assembly under the Single Transferable Vote system.

The Scottish Parliament has 73 single-member constituencies, with the remaining 56 seats being selected by the Additional Member System (AMS).  Until the passage of the Scottish Parliament (Constituencies) Act 2004, the constituencies of the Scottish Parliament were identical to those of the House of Commons.

The National Assembly for Wales has 40 constituencies which are identical to the Welsh constituencies of the House of Commons.  Its remaining 20 seats are selected by AMS.

The London Assembly has 14 single-member constituencies.  Its remaining 11 seats are selected by AMS.

The United States House of Representatives has 435 constituencies called "Congressional districts" each electing one member.  

The term "constituency" is usual in many countries, especially in members of the Commonwealth of Nations.
Cohesion

**Cohesion** may mean:

* Cohesion (chemistry): the intermolecular attraction between like-molecules.
* Cohesion (computer science): a measure of how well the lines of source code within a module work together to provide a specific piece of functionality.
* Cohesion (geography): the part of shear strength that is independent of the normal effective stress in mass movements.
* Cohesion (linguistics): the linguistic elements that make a discourse semantically coherent.
* Cohesion (music): a Manchester-based four-piece band playing uplifting indie guitar pop.
* Cohesion (structural): the sociological and graph theoretical conception and measurement for maximal group or graphical boundaries where related elements cannot be disconnected except by removal of a certain minimal number of other nodes
Silicon Graphics

**Silicon Graphics, Inc.** (Originally **Silicon Graphics Computer Systems**, often called **SGI**) was a company that made graphical workstation computers, high-performance computing servers, and graphics processing units. It was founded by Jim Clark in 1981 in Mountain View, California. 

It is important to the history of the MIPS processor architecture, UNIX (through their own UNIX product, IRIX) and later, Linux. 

## History 
In the 1980s Silicon Graphics sold graphics terminals (a type of computer that provides graphics for a server) based on the Multibus architecture used by early Sun Microsystems computers. Later, these computers, called the IRIS series, became standalone computers running an operating system known as **GL2**. 

After acquiring MIPS Computer Systems and the MIPS architecture rights, SGI moved to producing the Professional and Personal IRIS lines based on the MIPS R2000 and R3000 processors. These ran an operating system known as IRIX which continued active development and support until 2006.

SGI continued to develop the MIPS architecture and released many new computers based on the MIPS architecture and their custom graphics cards. By 1998 however a series of bad business decisions by then CEO Rick Belluzzo led to them losing money and they joined the Itanium alliance, which failed to deliver and cost SGI further money. 

By 2006, the MIPS R10000 product line had been extended all the way to the R16000 version, but was more expensive and slower than competing Intel X64, IBM POWER, and Itanium products. This combined with bankruptcy led SGI to change to Itanium products under the Altix product line. But by 2009, they were acquired by Rackable Systems which named themselves Silicon Graphics International. 

## References
Local government

**Local governments** are administrative offices that are smaller than a state or province.  The term is used to contrast with offices at nation-state level, which are referred to as the central government, national government, or (where appropriate) federal government.

What a local government does changes depending on what country it is in, and even when they are similar what it is called often varies.  Common names for local governments include state, province, région, départment, county, prefecture, district, city, township, town, borough, parish, municipality, shire and village.  However all these names are often used informally in countries where they do not describe a legal local government.

## Related pages 
* Decentralization
* Local Government Area

## References
## Other websites
* Department of Local and Regional Democracy and Good Governance—Council of Europe
* Local Governments at USA.gov 
* Japan Local Government Center
Stain

A **stain** is a spot that has another color than the material on which it is found. It can occur without intention in the case of domestic stains on fabric, cloth, or other material, or it can be intentional. Stains are used intentionally in a variety of fields, including research (biochemical staining), technology (metal staining), and art (wood staining, stained glass.)

Different types of material can be stained by different substances, and stain resistance is an important characteristic in modern textile engineering.  Various laundry techniques exist to attempt to remove or minimize existing stains, and stain removers are an important type of chemical in laundry detergents. Some stand-alone stain removers also exist.

## Substances that may create stains
* blood
* chocolate 
* coffee
* fruits and their juices, particularly orange juice
* grass
* grease
* ink (notably permanent marker)
* oil
* sauces (particularly tomato based)
* soda (particularly orange soda)
* sweat
* wine
* table salt
* talc, cornstarch or chalk
* borax
* lemon juice or lemon

### Fabrics
* carpet
* cotton
* leather
* silk
* various fabrics in shoes
* wool

### Stain removers
* bleach  (do not mix with ammonia)
* ammonia (do not mix with bleach)
* vinegar
* baking soda
* rubbing alcohol
* hydrogen peroxide
* cream of tartar
* sun
* club soda

## References
Ferrous

**Ferrous** is an adjective coming from the Latin *ferrum* (iron). One uses this word to indicate the presence of iron, mostly in metallurgy or related industries.
There are also non-ferrous metals, which are metals that have no iron in them at all.

**Ferrous** can also refer to iron in its +2 oxidation state.

*"Ferrous"* is also the name of a song by Peter Gabriel.

## Related pages
*Iron compounds
Carbon steel

**Carbon steel** or **plain-carbon steel**, is a metal alloy. It is a combination of two elements, iron and carbon. Other elements are present in quantities too small to affect its properties. The only other elements allowed in plain-carbon steel are: manganese (1.65% max), silicon (0.60% max), and copper (0.60% max). Steel with a low carbon content has the same properties as iron, soft but easily formed. With more carbon the metal gains hardness and strength but becomes less ductile and more difficult to weld. Higher carbon content lowers steel's melting point and its temperature resistance in general.

## Types of carbon steel 
Typical compositions of carbon are:

* **Mild (low carbon) steel**: approximately 0.3% carbon content with up to 0.4% manganese content (e.g. AISI 1018 steel). Less strong but cheap and easy to shape; surface hardness can be increased through carburizing.
* **Medium carbon steel**: approximately 0.30% to 0.45% carbon content with 0.60 to 1.65% manganese content
* **High carbon steel**: approximately 0.45% to 0.75%  carbon content with 0.30 to 0.90% manganese content.
* **Very high carbon steel**: upto 1.5% carbon content, specially processed to produce specific atomic and molecular micro structures. Manganese is often added to improve the hardenability of low carbon steels. These additions turn the material into a low alloy steel by some definitions, but AISI's definition of carbon steel allows up to 1.65% manganese by weight.

**Hardened steel** usually refers to quenched or quenched and tempered steel.

**Silver Steel** or high-carbon bright steel, gets its name from its appearance, due to the high carbon content. It is a very-high carbon steel, or can be thought of as some of the best high-carbon steel. It is defined under the steel specification standards BS-1407. It is a 1% carbon tool steel which can be ground to close tolerances. Usually the range of carbon is minimum 1.10% but as high as 1.20%. It also contains trace elements of 0.35% Mn (range 0.30%-0.40%), 0.40% Cr (range 0.4%-0.5%), 0.30% Si (range 0.1%-0.3%), and also sometimes sulfur (max 0.035%) and phosphorus (max 0.035%). Silver steel is sometimes used for making straight razors, due to its ability to produce and hold a micro-fine edge.

## Heat treatments 
, showing the temperature and carbon ranges for certain types of heat treatments.]]

The purpose of heat treating plain-carbon steel is to change the mechanical properties of steel, usually ductility, hardness, yield strength, and impact resistance.
## Footnotes 
## References 
* Oberg, E. *et al.*, (1996). "Machinery's Handbook," 25th ed., Industrial Press Inc.
* Smith, W.F. & Hashemi, J. (2006). "Foundations of Materials Science and Engineering," 4th ed., McGraw-Hill.
Yellowcake

**Yellowcake** is a type of uranium powder. Yellowcake is made from rocks and minerals with uranium inside, like *uraninite*, after they are changed in a factory. Yellowcake can be made into fuel for nuclear reactors, or it can be used in making atomic bombs.
Ductility

alloy. The local necking and the cup and cone fracture surfaces are typical for ductile metals.]]
 shows low ductility.]]

**Ductility** is when a solid material stretches under tensile strain. If ductile, a material may be stretched into a wire. Malleability, a similar property, is a material's ability to deform under pressure (compressive stress). If malleable, a material may be flattened by hammering or rolling.  

Both of these properties are aspects of plasticity.  Plasticity is how far a solid material can be deformed without fracture.  These properties are commonplace in metals, and are dependent on temperature and pressure.  This was investigated by Percy Williams Bridgman as part of his 1946 Nobel Prize–winning work on high pressures.

Ductility and malleability do not always go together. Gold has high ductility and malleability, but lead has low ductility and high malleability.  The word *ductility* is sometimes used to embrace both types of plasticity.

Gold, copper, aluminium, and steel have high ductility. 

## References 
## Related pages 
* Stress (mechanics)
MI

**MI** could mean:
* Myocardial infarction, commonly called a "heart attack"
* Michigan, a United States state
* *Mission: Impossible* - 1996 movie
* Mutual information
Minor Threat

**Minor Threat** was a hardcore punk band from Washington DC from the 1980s. Many other bands which played hardcore punk music in the United States were influenced by Minor Threat's music. Minor Threat's songs were usually short and fast. All of Minor Threat's records were released on the band's own Dischord Records label.

Minor Threat told their listeners they did not use illegal drugs or drink alcohol, which was called being "straight edge." 

## History
Ian MacKaye, Jeff Nelson, bassist Brian Baker, and guitarist Lyle Preslar formed Minor Threat in 1980. Their first records were *Minor Threat* and *In My Eyes* in 1981. The group toured through the United States.
  
Their song "Straight Edge" had lyrics (words) that told people they did not use illegal drugs or drink alcohol, which was called being "straight edge." Another song called "Out of Step" tells listeners not to smoke, drink, or have casual sex. People often thought that the band was telling others not to do these things but in interviews the band states that straight edge is a personal decision.

Minor Threat broke up in 1983. 

### Albums
* *Out of Step* (1983)

### Extended plays
* *Minor Threat* (1981)
* *In My Eyes* (1981)
* *Salad Days* (1985)

## References
## Other websites
* Official Website
* Minor Threat Profile by Dischord Records
Curse

A **curse** is a word which threatens the other person to have bad luck. Nobody knows if it really works or become true. Some people believe in them even so, that they become true by magic. For example, for fairy tales, the princes are cursed to become a beast or a frog (i.e. frog prince) by witches because of their bad behaviours. But in the end a princess saves them. 

There was also something called a "curse tablet" which Romans used to curse people they did not like. They would often let them drift to the river so that the curse will be carried to where that person who has the curse. But many curses are made when people are jealous and they want that person who has the curse to not do well. 

The opposite of a curse is a blessing.

## Related pages
*Evil eye
*Nithing pole
## References
*
Ventricular fibrillation

**Ventricular fibrillation** (often shortened to **VF** or **V-Fib**) is a serious type of irregular heart rhythm or cardiac arrhythmia. This is a Cardiac arrhythmia that requires immediate shocks with a defibrillator and cardiopulmonary resuscitation (CPR). If it’s not treated immediately, a patient can suffer brain damage or death. "Arrhythmia" means the heart is not beating normally.

## What is Ventricular Fibrillation? 
When a person is in ventricular fibrillation, the heart does not beat in any kind of normalized pattern. Instead, it quivers and twitches very quickly.    

This problem is called "ventricular" fibrillation because it affects the ventricles of the heart. The ventricles are the biggest parts of the heart. Their job is to pump blood (which carries oxygen) to the lungs or the rest of the body. When a person is in ventricular fibrillation, the ventricles cannot do this job. This means that the lungs, brain, and other organs will not get enough blood or oxygen.  

Ventricular fibrillation is a medical emergency. Without enough blood and oxygen, no part of the body can survive. If ventricular fibrillation continues for long enough, the blood will stop circulating around the body. The person's breathing and heart will stop. The person will die unless they get treatment quickly.

## Treatment 
Ventricular fibrillation can be stopped by shocking the heart with shocks from a Defibrillator. If a defibrillator is not available, cardiopulmonary Resuscitation (CPR) should be done to keep the blood flowing until an ambulance comes or a defibrillator is available.  

Doctors, paramedics or other medical personnel can also give special medicines called anti-arrhythmic medicines, which can make the heart start beating normally again. Some common anti-arrhythmic medicines are amiodarone and lidocaine. epinephrine and atropine or sodium bicarbonate can also be administered if necessary.  

If a person with ventricular fibrillation is treated right away, treatment is 90% successful (it works in 9 out of 10 people). But treatment gets 10% less successful after every minute (so if treatment starts after one minute, it will work in only 8 out of 10 people. After 5 minutes, it will work in only 4 out of 10 people.) So getting treatment as soon as possible is very important. If a person cannot be treated with medicine or a defibrillator right away, CPR will help keep blood and oxygen flowing through the person's body until treatment arrives.
 
In patients who are very likely to keep having ventricular fibrillation, a special defibrillator can be put into their chest by a surgeon. (This special defibrillator is called an "implantable cardioverter-defibrillator.") Any time the person goes into ventricular fibrillation, the defibrillator will give the person's heart an electric shock, to bring the heart back into a normal rhythm.

## Related pages 
* Troponin

## References
Warranty

In commercial and consumer transactions, a **warranty** is an obligation that an article or service that is sold has the quality the buyer can reasonably expect from the seller.

That often means that there must be a remedy. That means repair or replacement if the article or service is not as good as the warranty says. It is a breach of the warranty when the promise is broken, i.e., a product is defective or not as good as should be expected by a reasonable buyer.

In business and legal transactions, a warranty is an assurance by one party to the other party that certain facts or conditions are true or will happen. The other party is allowed to rely on that assurance and seek some type of remedy if it is not true or followed.

A warranty may be express or implied.

## Express warranty
An **express warranty** is typically a guarantee from the seller of a product that specifies the extent to which the quality or performance of the product is assured and states the conditions under which the product can be returned, replaced, or changed.

## Implied warranty
An implied warranty is one that arises from the nature of the transaction, and the understanding by the buyer.
To be "merchantable", the goods must reasonably conform to an ordinary buyer's expectations, i.e., they are what they say they are. For example, a fruit that looks and smells good but has hidden defects would violate the implied warranty of merchantability if its quality does not meet the standards for such fruit "as passes ordinarily in the trade".  

## Breach of warranty
A warranty is violated when the promise is broken; when goods are not as should be expected, at the time the sale occurs, whether or not the defect is apparent. Most warranties exclude parts that normally wear out, and supplies that must be periodically replaced as they are normally used up (e.g., tires and lubrication on a vehicle). 

Many people do not realize that extended warranties are not always provided through the manufacturer, but in some circumstances it may work to the consumer's benefit. For instance, when an auto warranty is provided through a dealership from the manufacturer, repairs on the vehicle are reimbursed at a lower negotiated rate.

## Legal aspects of warranties and disclaimers
In the United States, the rights and remedies of buyers and sellers of goods are governed by the Article 2 of the Uniform Commercial Code (UCC) as it has been adopted with variations from state to state.  

## Car warranty 
A car warranty is at least one year. Three years is more common. Five years is an extended warranty.

## Home warranty 
A home warranty protects against the high costs of home and appliance repair by offering insurance coverage for appliances and equipment in the house.

## References
## Related pages 
*Guarantee
## Other websites 
*(US) Federal Trade Commission: Warranty Information 
*Home Warranty Companies 
*Introduction to Laptop Warranties 
*American Home Shield
Tachycardia

**Tachycardia** is the fast beating of the heart. In adults, it refers to heart rates higher than 100 beats per minute. Tachycardia may be a normal physiological response to , but depending on the cause and how healthy the patient is, tachycardia could be harmful and need medical treatment. In some cases, tachycardia can cause death.

Tachycardia can be harmful in two ways. First, when the heart beats too rapidly, it may perform inefficiently. Second, the faster the heart beats, the more oxygen and nutrients the heart requires. This can be especially problematic for patients suffering from ischaemic heart disease.

## Other websites
Material fracture

A **fracture** is the separation of a body into more than one piece under the action of stress.

The word *fracture* is often applied to bones of living creatures or to crystals or crystalline materials, such as gemstones or metal. Sometimes, fractures can happen without the object actually separating into two or more pieces.
Shear stress

destroyed by shear.]]
**Shear stress** is a stress state where the stress is parallel to the surface of the material, as opposed to normal stress when the stress is perpendicular to the surface. 

Shear stress is relevant to themotion of fluids upon surfaces, which result in the generation of shear stress.
Also constructions in soil can fail due to shear; e.g., the weight of an earth-filled dam may cause the subsoil to collapse, like a small landslide.

## Related pages
* Scissors work by shear stress
Tension

**Tension** may mean:
* Tension (mechanics), in physics, a force related to the stretching of an object
* High-tension line, sometimes used to refer to electrical voltage
* Stress (biology), physiological or mental stress
* Tension (music), the perceived need for relaxation or release created by a listener's expectations
* Suspense, in a dramatic work, leaving the audience feeling uncertain and interested about the outcome of certain actions
* Tenseness, in phonetics, describes a certain sound quality
* Tension (band), a rock band

## Related pages
* Surface tension
* Tensile stress
* Tensile architecture
Tension (mechanics)

**Tension** is a reaction force applied by a stretched string (rope or a similar object) on the objects which  it. The direction of the force of tension is parallel to the string, towards the string.

Tension exists also inside the string itself: if the string is made up of two parts, tension is the force which the two parts of the string apply on each other. The amount of tension in the string determines whether it will break, as well as its vibrational properties, which are used in musical instruments.

## Related pages
* Force (physics)
* Pulley
* Stress (physics)
Shear

**Shear** as a noun could mean:
*Bias (textile), in clothing design, fabric may be cut on the shear
*Cosmic shear, an effect of distortion of image of distant galaxies due to deflection of light by matter, as predicted by general relativity (see also weak lensing and gravitational lens)
*Geological shear, a form of fault
*Guillotine (metalwork), also called a shear, a machine used to cut sheet metal
*Shear line (locksmithing), in lockpicking, where the inner cylinder ends and the outer cylinder begins in a cylinder lock
*Shear line (meteorology), an area of wind shear
*Shear (mathematics), a particular kind of linear mapping, also called transvections
*Shear stress in physics, refers to a stress state that will cause **shearing** (see verb below) when it exceeds a material's shear strength,
*Wind shear, a difference in wind speed or direction between two wind currents in the atmosphere

**Shear** as a verb or **shearing** could mean:
*Sheep shearing, the process of removing the wool from a sheep
*Shearing interferometer, in optics, a simple and very common means to check the collimation of beams by observing interference
*Shearing (physics), the deformation of a material substance in which parallel internal surfaces slide past one another,
*Skin, specifically, the tearing and splitting of the layers
Flow

**Flow** may mean:

*Flow, another name for "flux" in physics, which is the rate at which something travels through a given cross section
**In fluid mechanics, the word flow is often used to mean a complete description of the motion of a fluid.  See also volumetric flow rate
***In circulatory physiology, the word flow (e.g. of blood or lymph fluid) is commonly used as shorthand for regional flow, i.e., flow standardised to the volume or mass of a region of tissue under study (SI units: mL/s/mL or mL/s/g)
**Flow cytometry, abbreviated "flow", in certain laboratory applications, is a technique for counting, examining and sorting microscopic particles suspended in a stream of fluid
* Environmental flow, in ecology, the discharge or level of water necessary in a river or water source to sustain a healtly ecosystem
*Dataflow and workflow, terms that describe the flow of data in a mostly non-linear succession of computing steps
*Flow (mathematics), the one-dimensional (continuous, differentiable) action of a group, usually arising in the solution of differential equations
**Examples include geodesic flow, Hamiltonian flow and Anosov flow
*Network flow, an assignment of flow to the edges of a directed graph in graph theory
*Flow (psychology), the feeling of complete and energized focus in an activity, with a high level of enjoyment and fulfillment (a concept popularised by the book *Flow* by Mihaly Csikszentmihalyi)
*Flow (television), in television studies and programming, the sequence of television material from one element to the next
*Flow (journal), an online journal of television and media studies
*FLOW (band), a J-Pop group
*Flow binding system, abbreviated "flow", a US based manufacturer of proprietary snowboard bindings*flOw, a Flash game that will be available on the PlayStation 3
*Flow, the total value of sales or purchases in an accounting period, usually a quarter or a year in economics and accounting
*"Flow", in hip hop and poetry, a verb or noun described as the ability to start and maintain a verse of lyrics
*"Flow", the section of a skatepark which is meant to be ridden without pushing, usually consisting of banks, hills, funboxes, etc.
Applied mechanics

**Applied mechanics**, also known as **theoretical and applied mechanics**, is a branch of the physical sciences and the practical application of mechanics.  Applied mechanics examines the *response of bodies (solids and fluids) to external forces*.  Some examples of *mechanical systems* include the flow of a liquid under pressure, the fracture of a solid from an applied force, or the vibration of an ear in response to sound.  A practitioner of the discipline is known as a mechanician.  

Applied mechanics, as its name suggests, bridges the gap between physical theory and its application to technology.
Paleobiology

Matmor Formation, southern Israel.]]
**Paleobiology** is a branch of science which studies animals, plants and microbes  buried in rock.  These stoney items are called fossils. Paleobiology  combines biology with the study of these fossils. There are several branches of paleobiology:

* Paleobotany – Study of ancient plants
* Paleozoology
* Micropaleobiology
* Paleobiochemistry
* Paleoecology – Uses fossils to learn about how the environment was long ago
* Taphonomy
* Paleoichnology
* Stratigraphic paleobiology
* Evolutionary developmental paleobiology – Studies how animals changed over time

## History
Baron Franz Nopcsa von Felső-Szilvás started paleobiology in the late 19th century while working at the University of Vienna. He tried to learn how the animals lived, rather than merely put together their bones, as many geologists were doing at the time.
Mechanics

**Mechanics** is a branch of physics which looks at objects that are moved by forces (including other bodies, or forces of nature). A person working in this discipline is known as a mechanician.

Mechanics started in ancient Greece where Aristotle studied how things moved when they were thrown through the air. Since then Galileo, Kepler and Newton figured out a lot more about mechanics.

## Significance 
Mechanics started out as the study of parts of the world that are big enough for humans to see them. Mechanics studies the movement of all Matter in the universe. It studies gravity, strong and weak interactions, and Electromagnetism.

### Different Types of classical mechanics 
* Kinematics, the study of motion
* Astrodynamics, spacecraft navigation, orbital eccentricity, etc.
** Celestial mechanics, motions of planets and other astronomical objects
* Solid mechanics, elasticity, the properties of (semi-)rigid bodies
* Acoustics, sound in solids, fluids, etc.
* Hydraulics, fluids in equilibrium
* Applied / Engineering mechanics
* Statistical mechanics, large assemblies of particles
* Relativistic or Einsteinian mechanics, universal gravitation

### Newton 
Newton proposed three laws of motion. 
#An object will stay at a constant speed unless a force acts on it. 
#F= Ma: the overall force acting on an object is the mass of the object times the object's acceleration.
#For every action there is an equal but opposite reaction.

### Quantum mechanics 
The following are categorized as being part of Quantum mechanics:
* Particle physics, the motion, structure, and reactions of particles
* Nuclear physics, the motion, structure, and reactions of nuclei
* Condensed matter physics, quantum gases, solids, liquids, etc.
* Quantum statistical mechanics, large assemblies of particles

## Related pages
* Kinematics
* Mechanical engineering
* Physics

## Other websites 
Blogs:
* iMechanica: the web of mechanics and mechanicians
* Mechanics Blog by a Purdue University Professor
* The Mechanics program at Virginia Tech
Central line (disambiguation)

**Central line** or **Central Line** may refer to:

## Railway lines
* Central Line (Cape Town), a commuter rail service in Cape Town, South Africa
* Central line (London Underground), a line northwest/west to northeast through central London, England 
* Central line (Mumbai Suburban Railway), a public transit system serving Mumbai, Maharashtra, India
* Central Line (Newark), a former streetcar line in New Jersey, United States 
* Central Line (Sweden), a railway line between Sundsvall and Storlien
* Central Line (Tanzania), a rail line that runs west from Dar es Salaam to Kigoma
* Central Link, a light rail service in Seattle, Washington, United States 
* Central Subway, a light rail service in San Francisco, California, United States
* Chūō Line (*Central Line*), one of several train lines in Japan
* Jungang Line (disambiguation) (Korean *Central Line* railways)
* Moscow Central Circle, a commuter line encircling central Moscow, Russia

## Other
* Central Line (band), a 1980s British R&B, funk, disco band
* Central line (geometry), certain lines related to a given triangle
* Central line (medicine), a catheter placed into a large vein in the neck, chest or groin
* Central Artery, a section of freeway in Boston, Massachusetts