Aarushhh/wikipedia-simple-splitted huggingface dataset:
The Siberian Intervention (1918-1922) was part of a larger plan by the Western powers and Japan. They wanted to support the White Russians against the Bolshevik Red Army during the Russian Civil War. Other places included Northwest Russia, Crimea, Bessarabia, and the Caucasus.

Having occupied the Russian Maritime Provinces, the Allied Forces left by 1920. The Imperial Japanese Army stayed in Siberia until 1922.

Background
Background

The Siberian Intervention came quickly after the Russian October Revolution of 1917. The new Bolshevik government signed a separate peace treaty with Germany. That was a serious problem for the Entente powers. The treaty ended fighting for the Germans facing Russia. Germany could then move soldiers from east to west; against Europe.  The peace agreement also allowed Germany to get many supplies from Murmansk, Arkhangelsk and Vladivostok. In addition, a 50,000 man Czech Legion had been fighting on the side of the Allies. They became trapped. The Czechs were trying to fight their way out to the east to Vladivostok along the Trans-Siberian Railway. However, the Bolsheviks controlled that railway.
Great Britain and France decided to use military power and join the Russian Civil War against the Bolshevik government because of all of those problems. They had three goals: 
 stop Germany or the Bolsheviks from getting the Allied war supplies in Russia
 rescue the Czech Legion and return it to the European front
 restart the Eastern Front by helping create a White Russian government.
Active countries

Britain
The British had few soldiers sending only 1,500 troops to Siberia. These soldiers came from 9th Battalion, Hampshire Regiment and the 25th Battalion Middlesex Regiment.

Canada

The Canadian Siberian Expeditionary Force was commanded by Major General James H. Elmsley. The Canadian government approved the mission in August 1918. The Canadian soldiers were sent to Vladivostok to support the allied armies already there. There were 4,192 soldiers in the group. They returned to Canada between April and June 1919. The Canadians did little fighting. Fewer than 100 troops left the base area to go to Omsk. Those 100 worked as administrative staff for 1,500 British troops who were helping the White Russian government of Admiral Alexander Kolchak. Most Canadians stayed in Vladivostok. They did routine practice and worked as police in the unstable port city.

Italy
The Italian soldiers were most active in three areas: Irkutsk, Harbin, and Vladivostok.
Japan 
The Imperial Japanese Army sent 70,000 troops.

United States
The American Expeditionary Force Siberia was commanded by Major General William S. Graves. At its largest, it was 7,950 officers and enlisted men.
Allied intervention (1918-1919)
The Allies began to work together in Siberia in August 1918. The Japanese entered through Vladivostok and places along the Manchurian border. They sent more 70,000 soldiers. The Allies worried about Japanese plans because they sent such a large group. On September 5, the Japanese met the leading group of the Czech Legion. A few days later the British, Italian and French groups joined the Czechs to try to restart the war in the east. They tried to make a new battle line beyond the Ural Mountains. This meant that the European allies moved west. The Japanese had their own goals. They would not go west of Lake Baikal and stayed behind. The Americans were suspicious of Japanese plans.They also stayed behind to watch the Japanese. By November, the Japanese controlled all ports and major towns in the Russian Maritime Provinces and in Siberia east of the city of Chita.
In the summer of 1918 onwards, the Japanese army supported White Russian groups; the 5th infantry division and the Japanese-backed Special Manchurian Detachment of Grigory Semyonov took control over Transbaikalia. They started a White Transbaikalia government, but it did not last long.

References

Wars involving France
Wars involving Russia
Wars involving Japan
Wars involving the United States
Wars involving the United Kingdom
Russian Revolution
1910s conflicts
1920s conflicts
Mac OS X Lion is an operating system. It is the eighth major release of Apple's Mac OS X software line. It is made for Macintosh desktops, laptops, and servers. It was released on 20th July 2011 via the Mac App Store.

Lion was unveiled to the public at Apple's "Back to the Mac" event on October 20, 2010. It brings developments from iOS (Apple's mobile operating system for the iPhone, iPod Touch, and iPad), such as the App Store, to the Mac.

New or changed features
Some new features were announced at the "Back to the Mac" keynote, however more features are expected to be revealed closer to the release date.
Mac App Store — An application store similar to the iOS App Store. It will be made available to Macs running Mac OS 10.6 "Snow Leopard" on January 6, 2011. Like in iOS, it will provide many ways for shoppers to discover apps, one-click installation, and one-click updates of all or selected installed applications.
 Launchpad — An application launcher that presents an iOS-like icon grid of installed applications. Multiple pages and grouping apps in folders will be supported.
 Full-screen apps — Native, system-wide support for full-screen applications.
 Mission Control — Overview of running applications, putting together other Mac OS features including Exposé, Spaces, Dashboard, and full-screen apps.
 Multi-touch gestures — Similar to iOS, gestures performed using a multi-touch input device (e.g. Magic Mouse, Magic Trackpad) will allow the user to scroll, swipe to different pages, and enter Mission Control.
 Auto save — Documents automatically save, so users will not have to save their work.
Apps resume when launched — Applications resume in the same state when reopened.
 Autohiding Scrollbars — Scrollbars appear in the content area of the window and autohide when not scrolling (similar to iOS).
 Removal of "Aqua" UI — The "Aqua" look used in OS X since 2000 (first used in "iMovie 2") was replaced with a flatter, grey look.
References

Other websites

Mac OS X Lion at Apple.com

MacOS
The Planck time is the length of time at which no smaller meaningful length can be validly measured due to the indeterminacy expressed in Werner Heisenberg's uncertainty principle. Theoretically, this is the shortest time measurement that is possible. Planck time is roughly 10−43 seconds. However, to date, the smallest time interval that was measured was 10−21 seconds, a "zeptosecond."
One Planck time is the time it would take a photon travelling at the speed of light to cross a distance equal to one Planck length.
 
It is calculated from the Planck constant, which was first thought of by the physicist Max Planck in 1900. This work by Planck asserts that the energy of a photon is proportional to its frequency, and their relation can be put in terms of familiar units such as the joule by using the proportionality constant Planck gave us. Heisenberg's original quantum theory was improved by his teacher and colleague Max Born.
Born put Heisenberg's equation into a matrix form. Born immediately noticed that to calculate using these matrices, one matrix had to be multiplied by another matrix. In matrix multiplication, multiplying matrix P by matrix X gives a different result from the one obtained by multiplying matrix X by matrix P. He further noticed that the difference between the two matrices involves h, the Planck proportionality constant. It shows that one can never pin down things like P (momentum) and X (location) exactly. As a result, we cannot pin down a time any better than we can pin down a place or a momentum. We get closer and closer and then we reach the "Planck time."

Notation 
Planck time is usually noted tP, symbol made of the latin letter t lowercase, initial of latin word tempus ("time"), in italic, followed to the right and subscript, by the latin letter P uppercase, initial of the last name of Max Planck.
Definition 
Planck time is defined by :
,
where :
  is the Planck constant ;
  is the gravitational constant ;
  is the speed of light in a vacuum ;
  is Planck length.

Values 
In the International System of Units, the recommended value  for the Planck time is :
 s,
with a relative error of 10-4.

Related pages
Planck length

References

Physics
Units of time
Silva Barunaki "Sirvard" Kaputikyan (, 20 January 1919 in Yerevan, Republic of Armenia - 25 August 2006, Yerevan) was a 20th century prominent Armenian poet, writer, academic, and public activist. 

In February 1988, during a reception in Kremlin, Mikhail Gorbachev said that he and his wife, Raisa, greatly admired Kaputikyan's poetry. She appeared as herself in the 1992 documentary Parajanov: The Last Spring, about Sergei Paradjanov, a legendary film-maker of Armenian descent who was persecuted by Soviet authorities (Sayat Nova).

Awards 
Awards won by Kaputikyan during her career included:
 Named "Renowned Master of Arts" by the Armenian Soviet Socialist Republic (1971)
 Named "Renowned Worker of Arts" by the Georgian Soviet Socialist Republic (1980) 
 Received state prizes of the Union of Soviet Socialist Republics (USSR) (1952) and the Armenian Soviet Socialist Republic (1988)
 Received the Nosside Italian prize
 Awarded Ordens of St. Mesrob Mashtots (in Yerevan, Armenia) and Knyaginia Olga
Kaputikyan was also a member of International PEN.

1919 births
2006 deaths
Armenian writers
Armenian activists
Pointillism is a way of painting in which small separate dots of pure color are used to form images. The artist paints the picture with hundreds of tiny dots, mainly of red, yellow, blue and green, with white. The eye and mind of the viewer mix the colours to make different shades of these colours, as well as orange, purple, pink, and brown depending on the way the dots of colour are arranged. 

Georges Seurat, at first an Impressionist painter, and Paul Signac, developed this technique in 1886. Other important artists were Camille Pissarro and, in some paintings, Vincent van Gogh.  Art critics who saw their work, laughed at it and called it "Pointillism" as an insult. This name is still used, but is no longer thought of as an insult.
Traditionally, artists blend pigments (mix colours) on a palette. Pointillist painters do not mix the colours on the palette at all  they just use the colours straight from the tube. Traditional painters, and also impressionist painters, use many types of brushstrokes, and many textures of paint. The surface of the painting may have flat colour, lines, squiggles and dabs of paint. In a pointillist painting, every part of the picture is done in tiny dots, and most of the dots are about the same size. Pointillism is usually done in oil paints, because they are thick and do not run into each other when they are painted on the canvas.

Printing and television
Many colour printers and large printing presses use four colours to print in tiny dots of cyan (blue), magenta (red), yellow, and black. Televisions and computer monitors use a similar technique to show many different colors using only red, green, and blue.
Music
The name Pointillism is also given to a style of 20th-century music. Different musical notes are made separately from each other, giving a sound texture similar to pointillism. This type of music is also known as "punctualism" or "klangfarbenmelodie".

Gallery

Related pages
 Impressionism
 Post-Impressionists

References

Painting styles
In telecommunications, Baud is the unit to measure the symbol rate. If one symbol can be transmitted per second, this is equal to one Baud. The unit is named after Jean-Maurice-Émile Baudot a French telecommunications engineer who invented the Baudot code. The Baud rate is different from the gross bit rate, measured in bits/second. 

Various electric signal schemes invented in the 20th century such as Phase-shift keying can make bit rates much higher than signal rates. In another example, gigabit ethernet has a symbol rate of 125MBd. Gigabit ethernet uses pulse-amplitude modulation and can transmit two bits of payload data per symbol. Gigabit ethernet uses four balanced pairs for transmission.

It can transmit .

Telecommunications
Yun Chi-Young (Hangul: 윤치영, February 10 1898 - February 9 1996) was a Korean Independent Activist and politician, educators, diplomats. His nickname was 'DongSan' (동산, 東山). 1st Interior Minister (1948) of South Korea, 1st, 2nd and 3rd the National Assembly of South Korean. Younger Half-Uncle was Yun Bo-seon, 4th president of South Korea.

2nd  Republic of Korea Ambassador to French  1950 to 1951, 13th Mayor of Seoul City at December 17, 1963 to March 30, 1966.

Book 
 『Yun Chi-young's 20c』(윤치영의 20세기)

Related pages
 Yun Posun
 Rhee Syngman
 Yun Chi-ho
 Park Chung-hee
 Chang Myon
 Kim Gu

References 
 http://100.naver.com/100.nhn?docid=520742

1898 births
1996 deaths

Korean educators
Korean people
Anti-communists
South Korean politicians
Korean writers
Samuel Lewis Francis (June 25, 1923, San Mateo, California – November 4, 1994, Santa Monica, California) was an American painter and printmaker.  He was born in San Mateo, California, and studied botany, medicine and psychology at the University of California, Berkeley. He served in the United States Air Force during World War II before being injured in a plane crash. He was in the hospital for several years, and it was while he was there that he began to paint. Once he was out of the hospital he returned to Berkeley, this time to study art.

Francis was initially influenced by the work of abstract expressionists such as Mark Rothko, Arshile Gorky and Clyfford Still. He spent the 1950s in Paris, having his first exhibition there in 1952. While there he became associated with Tachisme. He later spent time in Japan, and some have seen an influence from Zen Buddhism in Francis’ work.
Francis spent some time in Paris making entirely monochromatic works, but his mature pieces are generally large oil paintings with splashed or splattered areas of bright contrasting colour. Areas of white canvas are often left to show through, and in later works, paint is sometimes confined to the edges of the canvas.

Francis returned to California during the 1960s and continued painting in Los Angeles.   During the final three decades of his career his style of large scale bright Abstract Expressionism was also closely associated with Color Field painting.  During the last year of his life, suffering from prostate cancer and unable to paint with his right hand after a fall, in a final burst of energy he used his left hand to complete a dazzling series of about 150 small paintings before he died.  He was buried in Olema, in Marin County, California.
After the death of the artist, the Samuel L. Francis Foundation, Inc. (also known as the "Samuel L. Francis Art Museum, Inc." or the "Sam Francis Foundation") was founded. The Foundation not only serves as his official Estate, but also has a mission "to research, document, protect and perpetuate the creative legacy of [Francis]." The U.S. copyright representative for the Francis Foundation is the Artists Rights Society.

As of 2008, the Foundation is working to create a Catalogue Raisonné of Francis's work. In addition to collecting information on known Francis works, they also have a page dedicated to "missing works" for which they are seeking any information interested parties may have.

In 2010, artist and filmmaker Jeffrey Perkins released the documentary "The Painter Sam Francis". The documentary includes film of Francis at work, filmed between 1968 and the early '90s together with interviews with friends, family, and professional associates of Francis.

References
References

 Marika Herskovic, American Abstract Expressionism of the 1950s An Illustrated Survey,  (New York School Press, 2003.) . pp. 130–133
 Peter Plagens, "Sunny side up - abstract expressionist painter Sam Francis," Artforum, March 1999.

Writings
 Aphorisms, Lapis, Santa Monica 1984
Other websites
 Samuel L. Francis official website 
 The Samuel L. Francis Foundation website
 Francis' page at the Tate Gallery  (includes a brief biography and images of his work)
 Sam Francis (artfacts)
 Gallery Delaive - Official representative of the Sam Francis estate for Europe
 examples of Sam Francis paintings
 Sam Francis Biography and Images: Hollis Taggart Galleries 
 Artists Rights Society, U.S. Copyright Representatives for Sam Francis
Sam Francis papers, 1920-2000, bulk 1950-1994. Research Library at the Getty Research Institute. Los Angeles, California. Although some papers remain with family and friends, this portion of the Francis archive gives a perspective on his life and work and documents the local context of production. The archive contains business and personal correspondence; project and business files with dealers and museums; files on the publications and prints of the Lapis Press; and photographic documentation of the artist, his work, family, friends, and collaborators. Also included are exhibition catalogs and related publications; gallery and museum posters; films and recordings made about Sam Francis; and samples of products designed by him for commercial projects.
1923 births
1994 deaths
American painters
American printmakers
People from San Mateo, California
Sodium periodate is a chemical compound. Its chemical formula can be NaIO4 (sodium metaperiodate) or Na5IO6 (sodium orthoiodate). It has sodium and periodate ions in it.

Properties
Sodium periodate is a colorless solid. It reacts with acids to make periodic acid. It breaks down when heated to make sodium iodate and oxygen gas. It is a strong oxidizing agent.

Preparation
It can be made by oxidation of sodium iodide with sodium hypochlorite in a nitric acid solution.

Uses
Sodium periodate can oxidize cellulose. It is also used as a biodegradable chemical in the human body. It is also used in organic chemistry reactions.

Related pages
Potassium iodate
Perbromic acid
Potassium perchlorate

Sodium compounds
Iodine compounds
7 Up is a product of a lemon-lime flavored caffeinate-free soft drink. The rights to the brand are held by Dr Pepper Snapple Group in the United States, and PepsiCo (or its licensees) in the rest of the world, including Puerto Rico. The origin of the name is unclear. It has been reformulated several times since its launch in 1929. 7-Up Soft Drink contains no caffeine and now has no artificial ingredients or preservatives, and only half the sodium as before. It is distributed by the 7-Up/Dr. Pepper company. The company promotes the product as having a crisper, more refreshing lemon-lime taste than before.

7 up is type of goods from the Dr Pepper company, it started produce at 1987. At other country, 7 up is goods from Pepsi Co. It first produced in Missouri, St.Louis.

References 

Soft drinks
Periodic acid (pronounced as per·io'·dic acid) is a chemical compound. It is also an acid. Its chemical formula is HIO4 or H5IO6. It has hydrogen and periodate ions in it.

Properties
Periodic acid is found as a colorless solution. It is a strong oxidizing agent, like perchloric acid. It breaks down when heated to iodine pentoxide and oxygen, as well as water. It does not form I2O7. It is found as HIO4 in dilute solution and H5IO6 in concentrated solution. When H5IO6 is heated, it turns into HIO4.

Preparation
It is made by reacting a periodate with a strong acid.

Uses
It is used to look at the structure of certain organic compounds.

Related pages
Perbromic acid
Sodium perbromate
Iodic acid

Iodine compounds
Acids
Periodate is an ion. Its chemical formula is either IO4- (metaperiodate) or IO65- (orthoperiodate). They are the salts of periodic acid. The iodine is in its +7 oxidation state. Periodates are similar to perchlorates. They are strong oxidizing agents. Sodium periodate is the most common periodate.

Related pages
Iodate
Hypoiodite

Iodine compounds
Ions
Potassium periodate is a chemical compound. Its chemical formula is KIO4. It has potassium and periodate ions in it.

Properties
Potassium periodate is a white solid. It is an oxidizing agent. It is similar to potassium perchlorate. It does not dissolve good in water. It makes potassium iodate and oxygen when heated.

Preparation
It is made by reacting potassium iodide with a strong oxidizing agent.

Uses
It is used to find out how much potassium is in something because it is one of the few potassium compounds that do not dissolve easily in water.

Related pages
Sodium periodate
Periodic acid
Iodic acid

Potassium compounds
Iodine compounds
Rey, Rayy, Ray, Rhages or Rages (; ; ) also known as Shahr-e-Rey (), is the oldest city in the state of Tehran, Iran. Rey today has been added into the Greater Tehran city. It is linked by the Tehran Metro to the rest of Tehran and has many industries and factories in use. A settlement began here 6,000 BCE as part of the Central Plateau Culture. The settlement was used as a capital by the Medes called Rhaga. In classical Roman geography it was called Rhagae. Its name dates back to the pre-Median.

Cities in Iran
Tehran Province
Iodine heptafluoride is a chemical compound. Its chemical formula is IF7. It contains iodine and fluoride ions. The iodine is in its +7 oxidation state.

Properties
It is a colorless gas with a moldy, stinky odor. Its melting point is at , and its boiling point is at . This means that it has a very narrow liquid range. It is a powerful oxidizing agent. It is very irritating to the skin. It is an interhalogen.

Preparation
It is made by reacting iodine pentafluoride with fluorine gas.

Related pages
Iodine trifluoride
Iodine pentoxide
Periodate

Iodine compounds
Fluorine compounds
Hypoiodous acid is a chemical compound. It is also an acid. Its chemical formula is HIO. It has hydrogen and hypoiodite ions in it.

Properties
Hypoiodous acid is very unstable. It easily disproportionates to iodine and iodic acid. It is a disinfectant and oxidizing agent.

Preparation
It is made by reacting mercury(II) oxide with iodine.

Uses
It is too unstable to be used, although people think that this is what makes iodine a disinfectant.

Related pages
Iodic acid
Periodic acid

Acids
Iodine compounds
Hypoiodite is an ion. Its chemical formula is IO-. It is very unstable. It easily disproportionates to iodide and iodate. It is made by reacting iodine with a base. The iodine is in its +1 oxidation state. It is the salt of hypoiodous acid.

Related pages
Iodine monochloride
Iodine trifluoride

Iodine compounds
Ions
Iodine trifluoride is a chemical compound. Its chemical formula is IF3. It has iodine and fluoride ions in it. The iodine is in its +3 oxidation state.

Properties
Iodine trifluoride is a yellow solid. It breaks down above -28°C. It is made by reacting very cold fluorine with iodine.

Related pages
Iodine tricloride
Iodine pentafluoride
Iodine heptafluoride

Iodine compounds
Fluorine compounds
Iodine trichloride is a chemical compound. Its chemical formula is ICl3. It has iodine and chloride ions in it. The iodine is in the +3 oxidation state.

Properties 
Iodine trichloride is a yellow solid. It melts at . It conducts electricity when it melts. It is a strong oxidizing agent. It is an interhalogen.

Preparation 
It is made by reacting a lot of cold iodine with liquid chlorine. It can also be made by heating liquid iodine with chlorine gas at .

Related pages 
Iodine pentafluoride
Iodine monochloride
Iodine heptafluoride

Iodine compounds
Chlorine compounds
Silver iodate is a chemical compound. Its chemical formula is AgIO3. It has silver and iodate ions in it. The silver is in the +1 oxidation state.

Properties 
Silver iodate is a colorless solid. It does not dissolve in water. It is an oxidizing agent.

Preparation 
It is made by reacting silver nitrate with sodium iodate.

Related pages 
Potassium iodate
Sodium periodate
Sodium bromate

Silver compounds
Iodine compounds
SemEval (Semantic Evaluation) is a series of workshops that focus on evaluating computer systems that  interpret the meaning of human language (aka  Computational Semantic systems). 

Computers
Iodate is an ion. Its chemical formula is IO3-. The iodine is in the +5 oxidation state. It can be made by reduction of periodate. They are similar to chlorates. They react with acids to make iodic acid. They are salts of iodic acid. An example would be sodium iodate.

Related pages
Iodine compounds

Iodine compounds
Ions
Iodine pentafluoride is a chemical compound. Its chemical formula is IF5. It has iodine and fluoride ions. The iodine is in its +5 oxidation state.

Properties
Iodine pentafluoride is a pale yellow liquid. It is an interhalogen. It is also a powerful oxidizing agent. It reacts with water to make hydrofluoric acid.

Preparation
Iodine pentafluoride is made by burning iodine in fluorine gas.

Uses
It is used in organic chemistry (amine to nitrile conversion after hydrolysis).

Related pages
Iodine heptafluoride
Iodine trifluoride

Iodine compounds
Fluorine compounds
Iodine pentoxide, also known as iodine(V) oxide and diiodine pentoxide is a chemical compound. Its chemical formula is I2O5. It has iodine and oxide ions. The iodine is in its +5 oxidation state.

Properties
Iodine pentoxide is a white solid. It breaks down to iodine and oxygen when heated. It reacts with carbon monoxide to make carbon dioxide and iodine. It is a strong oxidizing agent. It reacts with water to make iodic acid.

Preparation
Iodine pentoxide is made by heating iodic acid to  in dry air.

Uses
It is used to see how much carbon monoxide is in a sample of gas.

Related pages
Iodine pentafluoride
Iodine trifluoride
Iodine monochloride

Iodine compounds
Oxides
Potassium iodate is a chemical compound. Its chemical formula is KIO3. It has potassium and iodate ions in it.

Properties
Potassium iodate is a white solid. It is a strong oxidizing agent. It is similar to potassium bromate and potassium chlorate. It reacts violently with many reducing agents.

Preparation
Potassium iodate is made by reacting iodic acid with potassium hydroxide or by reacting iodine with potassium hydroxide. This second reaction makes the iodide and the iodate.

Uses
Potassium iodate is used to add iodine to salt. It is better than potassium iodide because it does not oxidize to iodine and evaporate like potassium iodide does. It is sometimes used in flour just like potassium bromate. 

It is also used for radiation protection. A nuclear explosion can make radioactive iodine, which goes into the thyroid and can make cancer. Eating potassium iodate makes the thyroid full of nonradioactive iodine and prevents radioactive iodine from going in. It lasts longer than potassium iodide.
Related pages
Potassium periodate
Periodic acid
Hypoiodous acid

Potassium compounds
Iodine compounds
Sodium iodate is a chemical compound. Its chemical formula is NaIO3. It has sodium and iodate ions in it.

Properties 
Sodium iodate is a colorless solid. It is similar to sodium chlorate. It is a strong oxidizing agent. It reacts with sodium hypochlorite to make sodium periodate. It can catch things on fire.

Preparation 
It is made by dissolving iodic acid or iodine in sodium hydroxide solution. Iodine dissolving also makes sodium iodide.

Uses 
It is used to make sodium periodate.

Related pages 
Potassium iodate
Potassium periodate
Potassium chlorate

Potassium compounds
Iodine compounds
Tuff (from Italian tufo) is a type of rock produced by the eruption of volcanoes.

It consists of consolidated  volcanic ash ejected from vents during a volcanic eruption. Rock with more than 50% tuff is called tuffaceous. The chemical and mineral composition of tuff varies according to what was in the molten magma.

Volcanic ash 
In a volcanic eruption, Magma is blown apart by volcanic gases and steam.  The products are volcanic gases, lava, steam, and tephra (fragments).  The solid material produced and thrown into the air is called tephra, regardless of composition or fragment size.  If the pieces of ejecta are small, the material is called volcanic ash, defined as such particles less than 2 mm in diameter, sand-sized or smaller.  These particles are small, slaggy pieces of magma and rock that have been tossed into the air by outbursts of steam and other gases.

Structure

Breccias
Breccias 

Among the loose beds of ash that cover the slopes of many volcanoes, three classes of materials are represented. 
 True ashes of the kind described above.
 Lumps of the old lavas and tuffs forming the walls of the crater, which have been torn away by the violent outbursts of steam.
 Pieces of sedimentary rocks from the deeper parts of the volcano that were dislodged by the rising lava and are often baked and recrystallized by the heat. 

In some great volcanic explosions nothing but materials of the second kind were emitted, as at Mount Bandai in Japan in 1888. There have also been many eruptions in which the quantity of broken sedimentary rocks that mingled with the ash is very great. 

These materials, in contrast to true ashes, tend to occur in angular fragments. When they form a large part of the mass the rock is more properly a 'volcanic breccia' than a tuff. A breccia is a rock with sharp-edged fragments in it.
Agglomerate 
The ashes vary in size from large blocks twenty feet or more in diameter to the minutest impalpable dust. The large masses are called 'volcanic bombs'; they have mostly a rounded, elliptical or pear-shaped form owing to rotation in the air before they solidified. Many of them have ribbed or nodular surfaces, and sometimes they have a crust intersected by many cracks like the surface of a loaf of bread. Any ash in which they are very abundant is called an agglomerate.

Consolidation
A tuff of recent origin is generally loose, but the older tuffs have usually been cemented together by pressure and the action of infiltrating water. This makes rocks which, while not very hard, are strong enough to be used for building purposes (e.g. in the neighborhood of Rome).
Under water 
Many volcanoes stand near the sea, and the ashes cast out by them are mingled with the sediments that are gathering at the bottom of the waters. In this way ashy muds or sands or even in some cases ashy limestones are formed. As a matter of fact most of the tuffs found in the older rock formations contain mixtures of clay, sand, and sometimes fossil shells, which prove that they were beds spread out under water.

Repeated eruptions 
During some volcanic eruptions a layer of ashes several feet in thickness is deposited over a considerable district, but such beds thin out rapidly as the distance from the crater increases, and ash deposits covering many square miles are usually very thin. 

The showers of ashes often follow one another after longer or shorter intervals, and hence thick masses of tuff, whether of subaerial or of marine origin, have mostly a stratified character. In the fine beds it is often developed in great perfection.

Welded tuff
Welded tuff 

Welded tuff is a pyroclastic flow of lava which was hot enough to weld together. During welding, the glass shards and pumice fragments adhere together (necking at point contacts), deform, and compact together. 

A hot lava flow welded by heat can be highly voluminous, such as the Lava Creek Tuff erupted from Yellowstone Caldera in Wyoming 640,000 years ago. Lava Creek Tuff was at least 1000 times as large as the deposits of the May 18, 1980 eruption of Mount St. Helens. It had a Volcanic Explosivity Index (VEI) of 8—greater than any eruption known in the last 10,000 years.

Basaltic tuffs 

Basaltic tuffs are occur widely. They are found in Skye, Mull, Antrim and other places, where there are tertiary volcanic rocks; in Scotland, Derbyshire and Ireland among the carboniferous strata; and among the still older rocks of the Lake District, southern uplands of Scotland and Wales.
Basaltic tuffs are black, dark green or red in colour. They vary greatly in coarseness. Often submarine, they may contain shale, sandstone, grit and other sedimentary material, and are occasionally fossiliferous. Recent basaltic tuffs are found in Iceland, the Faroe Islands, Jan Mayen, Sicily, Sandwich Islands, Samoa, etc.

Notes 

Igneous rocks
Copper(I) iodide, also known as cuprous iodide, is a chemical compound. Its chemical formula is CuI. It has copper and iodide ions in it. The copper is in its +1 oxidation state.

Properties
Copper(I) iodide is a white solid. It does not dissolve in water. It easily turns tan or brown. It is a reducing agent. The iodide easily oxidizes to iodine. Copper does not form a stable copper(II) iodide; copper(II) iodide breaks down right away to make copper(I) iodide and iodine. It dissolves in concentrated iodides like potassium iodide. When it is diluted, it makes copper(I) iodide again.

Preparation
It can be made by reacting iodine and copper in concentrated hydroiodic acid. Another way would be to react copper(II) sulfate and potassium iodide. This makes copper(II) iodide which as said before breaks down right away to make iodine and copper(I) iodide.

Uses
It is used to make organic compounds. It is also used to make clouds rain. It is used to make nylon resistant to heat. It can be used to put iodine to foods.
Related pages
Copper(I) bromide
Copper(I) chloride

Copper compounds
Iodine compounds
Copper(I) bromide, also known as cuprous bromide, is a chemical compound. Its chemical formula is CuBr. It has copper and bromide ions in it. The copper is in its +1 oxidation state.

Properties 
Copper(I) bromide is a colorless solid. It turns green when in air. It does not dissolve in water. It is a reducing agent.

Preparation 
Copper(I) bromide is made by reacting copper(II) bromide with any sulfite and any bromide salt. This reaction makes hydrogen bromide gas.

Uses 
It is used in organic chemistry. It is used to make organic compounds that have copper in them.

Related pages 
Copper(I) iodide
Copper(I) chloride

Copper compounds
Bromine compounds
Copper(II) bromide, also known as cupric bromide, is a chemical compound. Its chemical formula is CuBr2. It has copper and bromide ions in it. The copper is in its +2 oxidation state.

Properties
Copper(II) bromide is a grayish-black solid. Most copper(II) compounds, except for the oxide, are bright blue or green. It can be reduced to copper(I) bromide.

Preparation
It can be made by dissolving copper(II) oxide in hydrobromic acid. It can also be made by reacting copper and bromine.82

Uses
Copper(II) bromide is used in lasers. It is also used to add bromide ions to other chemical compounds in organic chemistry.

Related pages
Copper(II) chloride
Copper(I) iodide

References

Copper compounds
Bromine compounds
Fading Echoes is the second book in the fourth Warriors series, Omen of the Stars. It includes multiple points of view: Dovepaw and Ivypaw, two sisters, and Jayfeather and Lionblaze, two brothers. All of these cats are in ThunderClan.

The story takes place in a forest around a fictional lake. The forest is populated by groups of feral cats, who live in groups that call themselves Clans. The four Clans are ThunderClan, ShadowClan, WindClan, and RiverClan. The cats usually train to become warriors, who hunt and fight for their Clans.

Plot

Dovepaw's story 
Dovepaw strengthens her ability to hear farther than any cat around the lake, while her bond with her sister, Ivypaw, dwindles. This is because Dovepaw cannot share the secret of her power with any cat except for Lionblaze and Jayfeather. 

Dovepaw tries to make friends with a ShadowClan warrior named Tigerheart, but she cannot, as the fact that they are from different Clans keeps them apart.
Later, Dovepaw saves most of ThunderClan by sensing that a tree is about to fall into their camp, and evacuating them in time.

Jayfeather's story 
Jayfeather discovers that some Clan cats are being trained by Dark Forest cats (the Dark Forest is where bad Clan cats' spirits go when they die). This means that the Clan cats will have to fight the Dark Forest cats and the Clan cats training there.

Ivypaw's story 
Ivypaw begins to train in the Dark Forest. She has an argument with her sister, Dovepaw, and their bond starts to weaken. Later, she fakes a sign that says the cats should enter a battle, which results in two deaths.

Warriors books
Starlight is the fourth book in the second series of Warriors, called Warriors: The New Prophecy. The book is told from three different points of view: Leafpool and Squirrelflight, two sisters, and Squirrelflight's love interest, Brambleclaw.

This book takes place in a forest around a fictional lake. The forest is populated by groups of feral cats, who live in groups that call themselves Clans. The four Clans are ThunderClan, ShadowClan, WindClan, and RiverClan. The cats usually train to become warriors, who hunt and fight for their Clans.

Plot
Plot

Leafpool 
Leafpool has to care for ThunderClan with her teacher, Cinderpelt. She and Cinderpelt are medicine cats, meaning that they heal the cats of their Clan. She finds a place called the Moonpool, where the Clans can contact the spirits of their ancestors. She eventually falls in love with a WindClan warrior called Crowfeather (which is forbidden, as Leafpool and Crowfeather are from different Clans). Leafpool also discovers that Brambleclaw has started to train with Tigerstar and Hawkfrost, his evil father and brother, in dreams. She wonders if he is truly loyal to ThunderClan.

Squirrelflight 
Squirrelflight discovers a place where ThunderClan can live. She begins to struggle with her emotions for two male cats, Brambleclaw and Ashfur. She likes Ashfur more for a while when she finds out that Brambleclaw has been training with evil cats. She wonders if Brambleclaw is loyal to ThunderClan. Eventually, though, she decides that she loves Brambleclaw, and chooses him over Ashfur.
Brambleclaw 
Brambleclaw starts dreaming of a place called the Dark Forest, a place where the spirits of evil Clan cats go when they die. In those dreams, he trains with Tigerstar and Hawkfrost, his evil father and brother.

Warriors books
Michael Elliot Epps (born November 18, 1970) is an American actor and comedian. His movies include Next Friday, Friday After Next, and Open Season 2. Epps' trademark is a voice similar to Martin Lawrence in the original Open Season. He replaced Lawrence as the voice of Boog in Open Season 2. Lawrence and Epps also starred in the comedy Welcome Home Roscoe Jenkins. In Open Season 3, he was replaced by Matthew J. Munn.

Other websites

1970 births
Living people
American stand-up comedians
20th-century American comedians
American movie actors
African American actors
Actors from Indiana
Comedians from Indiana
A proposition is a term in philosophy and logic. It is a statement which has a truth value, meaning it can be proved to be true or false. For a proposition to be valid, it must be possible to prove the proposition is either true or false. Many teachers and students of logic use the term statement and proposition to mean the same thing. Propositions are also often represented by capital letters such as ,  and .  

It is possible to express the same proposition in many way. Proposition are only concerned with actual meaning, not the way the proposition is expressed. Propositions can look different, yet still mean the same thing. When two different propositions mean the same thing, they are said to be synonymous, meaning each statement has the same meaning.
For example, "Snow is white" (in English) and "Schnee ist weiß" (in German) are different sentences, because they are written in different languages. However, they mean exactly the same thing: snow is white. No matter what language the statement is written in, it will mean the same thing. As a result, these statements are synonymous. 

In Aristotelian logic, a proposition is a specific kind of sentence that confirms or denies an action or predicate took place through a subject. Aristotelian propositions take forms like "All men are mortal" and "Socrates is a man". In each sentence, the subject (men, Socrates) has a status (are mortal, is a man) which can be regarded as true or false.
In logical positivism, a proposition whose truth value cannot possibly be decided is meaningless (Quine, for instance, believes that propositions generally have no clear criterion of identity). For example, statements about the existence of deities cannot be proved under logical positivism. Because the statements have no truth value, a logical positivist would consider propositions about deities (such as "God exists" or "God does not exist") to have no logical meaning.

Related pages 
Axiom
Propositional logic
Predicate logic

References 

Philosophy
Logic
Karst is a geological system of rocks where water has eroded (dissolved) the bedrock. If it is very extensive, karst can be a geographical or topographical feature. It is classed as a badland if it difficult to travel through the environment, which it often is.

Almost always, karst is formed in carbonate rocks, such as limestone or dolomite. Since carbonate sedimentary rocks are very common, karst areas occur all over the world.

Many karst regions display distinctive surface features, with sinkholes being the most common. However, karst surface features may be absent where the soluble rock is mantled (covered), such as  by a non-soluble rock strata on top of the carbonate strata. Some karst regions include thousands of caves, and the water is generally underground.
The world's largest karst area is the Nullarbor Plain, part of the area of flat, almost treeless, dry country of southern Australia. It is on the Great Australian Bight coast with the Great Victoria Desert to its north. It is the world's largest single exposure of limestone bedrock, and occupies an area of about . At its widest point, it stretches about  from east to west across the border region between South Australia and Western Australia.
Sinkholes 
Many parts of the world suffer from sinkholes which form when karsts are underground. Beneath the flat surface of the land in Florida, Guatemala City and elsewhere are vast systems of limestone. Water running through the limestone is dissolving the limestone away, leaving huge caverns. Without warning, huge holes appear in the surface, causing great damage. Practically the whole of Florida is sitting on a gigantic karst system, as are several countries in Central America. The area round Tampa is especially at risk, and there is a huge karst system under Mexico City. According to a senior geochemist, there are as many as 15,000 sinkholes in Illinois.

The world's deepest sinkhole is China's Xiaozhai Tienkeng at 2172ft (662m). 

The Qattara Depression in Egypt is part of the Libyan Desert. It is roughly 50 miles (80km) by 75 miles (121km) in surface area. It is the world's largest natural sinkhole. It lies below sea level and is covered with salt pans, sand dunes and salt marshes.

Karst aquifers
Karst aquifers 

In the United States, about 40% of the groundwater used for drinking comes from karst aquifers. Well-known examples are Carlsbad Caverns and Mammoth Cave. Karst aquifers are a vital resource in the US. About 20 percent of the land surface in the US is karst. Other parts of the world with large areas of karst include the Caribbean, China, and Australia.

The karst hydrogeology is a network of fissures, fractures, and runways in permeable rock. Most of inflow occurs through a network of openings. Groundwater is held in storage in the rocks. Karst is common also in Mexico, especially near where the meteorite hit in the Yucatan. There are also large areas of karst in the Caribbean, China, and Australia.

Related pages 
Aquifer
Limestone

References 

Sedimentary rocks
Badlands
PubMed Central is a free database of scientific literature in biomedical and life sciences. It is on the Internet. It grew from the online Entrez PubMed biomedical literature search system.  PubMed Central was developed by the U.S. National Library of Medicine (NLM) as an online archive of biomedical journal articles. It was started in 2000. As of 2021, it had over 7 million science papers in it.

All the words in the PubMed Central articles can be read freely. Some publishers, though, do not show their articles for some time after they publish them on paper (usually about six months).

History

PubMed Central was started in 2000.  At first, it only had papers from Proceedings of the National Academy of Sciences and Molecular Biology of the Cell.  People can add older papers to PubMed Central.  The oldest papers in PubMed Central are from the 1700s.
As of September 2004, PubMedCentral, PubMed, and related NLM services had about 1,300 hits every second, and gave 1.3 terabytes of data every day. The Library of Congress and the British Library showed support for the National Library of Medicine (NLM). It has also been popular with journal service providers.

PubMed Central and PubMed

PubMed Central is different from PubMed. The regular PubMed has papers' titles and abstracts, and PubMed central has the whole paper.  Scientists call this "full text."

PMCID

The PubMed Central Identifier (PMCID) is an ID tag for papers written by scientists and doctors.  It is like an ISBN is for books.  It shows the reader where to find the paper in the PubMed Central database.

References

Other websites 
PubMed Central
PubMed Central FAQ
National Institutes of Health Submission System (NIHMS)
NIH Public Access Policy

Public databases
Science websites
2000 establishments
The Medical University of Innsbruck (German: Medizinische Universität Innsbruck) is a university in Innsbruck, Austria. It used to be one of the four historical faculties of the Leopold-Franzens-Universität Innsbruck, but it became an independent (by itself) university in 2004.

History 
The medical tradition dates back long before the university began. The first hospital began in the silver-mining city of Schwaz nearby in 1307. Because people grew as years went by, a medical faculty was added to the university, begun in 1669 by Emperor Leopold I, making it the first of its kind in the Alpine region.

Nobel Prize laureates 
 Fritz Pregl, 1923 (chemistry - for his contributions to quantitative organic microanalysis) 
 Adolf Windhaus, 1928 (chemistry - for his work on sterols and their relation to vitamins)
 Hans Fischer, 1930 (chemistry - for the synthesis of haemin)

Other websites 
 
 Study in Austria: A Guide 

Colleges and universities in Austria
Innsbruck
2004 establishments in Europe
Medical education
Dolomite is the name of a sedimentary carbonate rock and a mineral, both composed of calcium magnesium carbonate CaMg(CO3)2 

As a mineral, it is found in crystals. Dolomite rock  (or 'dolostone') is mostly made of the mineral dolomite. 

Limestone that is partially replaced by dolomite is referred to as dolomitic limestone. In the old U.S. geologic literature it is called magnesian limestone. Dolomite was first described in 1791 for exposures in the Dolomite Alps of northern Italy.

Carbonate rocks
Minerals
Sedimentary rocks
Gravel is small, loose, rock particles. It is any loose rock that is larger than 2 mm (0.079 in) in its smallest dimension (about 1/12 of an inch) and no more than 64 mm (2.5 in).

Small gravel is composed of granules (>2 to 4 mm/0.079 to 0.16 in). Large gravel is called pebbles (>4 to 64 mm/0.16 to 2.5 in). 

Particles smaller than gravel are sand, larger particles are cobbles.

Gravel and sand are used for road surfaces, and for cement and Tarmac. Mixtures of gravel and sand mixed with various crushed material, are known as aggregate in the trade. This is used for drainage in the basement of roads, and other purposes. Mixture of stones and resin is also used to pave footpaths, driveways, etc. This mixture is known as Resin Bonded Gravel.
Origin 
Natural gravel comes from ancient beaches which have not consolidated (turned into solid rock). In effect, beaches from (for instance) the Jurassic are dug up in quarries. The material is then sifted into size categories. The gravel and sand is then sold on to engineering companies. Most natural sand and gravel is silica, SiO2, in its chemistry. This is very hard-wearing.

However, if the material is originally in hard rock form, then it is first crushed. This enables the industry to offer other materials such as granite or limestone, originally solid rock, as gravel.

The open-cast mining and processing of gravel, sand and aggregate is a huge world-wide industry, sometimes called "conglomerates".

References 

Rocks
Mining
A cornet is a brass instrument that is similar to the trumpet. It is part of the higher-brass family, together with trumpets and French horns.

Other websites

Brass instruments