recursal/SuperWikiNEXT-32B huggingface dataset:
Comparison of different diffraction based spectrometers: Reflection optics, refraction optics, fiber optics
A **spectrometer** is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum.

The independent variable is usually the wavelength of the light. 
The variable measured is most often the light's intensity but could also, for instance, be the polarization state. A spectrometer is used in spectroscopy for producing spectral lines and measuring their wavelengths and intensities. Spectrometer is a term that is applied to instruments that operate over a very wide range of wavelengths, from gamma rays and X-rays into the far infrared.

In general, any particular instrument will operate over a small portion of this total range because of the different techniques used to measure different portions of the spectrum. Below optical frequencies (that is, at microwave, radio, and audio frequencies), the spectrum analyzer is a closely related electronic device.

Spectroscopes
-------------

Spectrometers are used in spectroscopic analysis to identify materials. Spectroscopes are used often in astronomy and some branches of chemistry. Early spectroscopes were simply a prism with graduations marking wavelengths of light. Modern spectroscopes, such as monochromators, generally use a diffraction grating, a movable slit, and some kind of photodetector, all automated and controlled by a computer. The spectroscope was invented by Gustav Robert Georg Kirchhoff and Robert Wilhelm Bunsen.

Reference works
---------------

* How to work with the spectroscope : a manual of practical manipulation with spectroscopes of all kinds

1882; Browning, John (1835-1925) NOT\_IN\_COPYRIGHT - online full-text download

Related pages
-------------

* Spectroscopy

Other websites
--------------

* How to design a spectroscope Archived 2012-04-23 at the Wayback Machine
* A CD spectrometer Build from CD and cereal box - Spectrographs of common light sources
* Supplement: Build Yourself a Simple Hand-Held Spectrograph Archived 2007-10-16 at the Wayback Machine Sample spectra
* SPECTROSCOPY FOR THE SCHOOL Archived 2012-05-16 at the Wayback Machine Build a simple spectroscope from a CD
* CD spectrometer CD + cardboard tube or cereal box
* Construction photos, razor-blade slit
* MiniSpectroscopy displays a visual representation (a "spectroscope view") of a sample spectrum simultaneously with a graphical (intensity vs. wavelength) representation.
Measures 1-4 of Chopin's Prelude in D-flat Major, Op. 28, No. 15 ("Raindrop")
The **Prelude Op. 28, No. 15,** by Frédéric Chopin is known as the "Raindrop" prelude. It is one of the 24 Chopin preludes. This is the longest of the preludes. It lasts between five and seven minutes. The prelude is famous for its repeating A-flat. This note appears throughout the piece. It sounds like raindrops to many listeners. It is known for it's repetitive raindrop motif.

Composition
-----------

Some of the Preludes were written during Chopin and George Sand's stay at a monastery in Valldemossa, Majorca in 1838.  In her *Histoire de ma vie*, Sand told how one evening she and her son Maurice, returning from Palma, Majorca, in a terrible rainstorm, found a frantic Chopin who cried, "Ah! I knew well that you were dead." While playing his piano he had a dream:

> "He saw himself drowned in a lake. Heavy drops of icy water fell in a regular rhythm on his breast, and when I made him listen to the sound of the drops of water indeed falling in rhythm on the roof, he denied having heard it. He was even angry that I should interpret this in terms of imitative sounds. He protested with all his might – and he was right to – against the childishness of such aural imitations. His genius was filled with the mysterious sounds of nature, but transformed into sublime equivalents in musical thought, and not through slavish imitation of the actual external sounds."
> 
> 

Sand did not say which prelude Chopin played for her at that time. Most music critics think it was no. 15, because of the repeating A flat, with its suggestion of the "gentle patter" of rain. Peter Dayan points out that Sand accepted Chopin's protests that the prelude was not an *imitation* of the sound of raindrops, but a *translation* of nature's harmonies within Chopin's "génie". Frederick Niecks says that the prelude "rises before one's mind the cloistered court of the monastery of Valdemosa, and a procession of monks chanting lugubrious prayers, and carrying in the dark hours of night their departed brother to his last resting-place.

Description
-----------



Prelude Op. 28, No. 15 in D-flat major

*(left)* Chopin, 1849

---

*Problems playing this file? See media help.*

The prelude opens with a "serene" theme in D flat. It then changes to a "lugubrious interlude" in C sharp minor, "with the dominant pedal never ceasing, a basso ostinato". The repeating A flat, which has been heard throughout the first section, here becomes more insistent. Following this, the prelude ends with a repetition of the original theme. Niecks says, "This C sharp minor portion...affects one like an oppressive dream; the re-entrance of the opening D flat major, which dispels the dreadful nightmare, comes upon one with the smiling freshness of dear, familiar nature – only after these horrors of the imagination can its serene beauty be fully appreciated.

Related pages
-------------

* Preludes (Chopin)

Other websites
--------------

* Prelude No. 15 at YouTube, performed by Martha Argerich
* Prelude No. 15 at YouTube, performed by Valentina Igoshina
textile arts in ancient Egypt
This portrait illustrates the practical, decorative, and social aspects of the textile arts. Henry Frederick, Prince of Wales by Robert Peake the Elder, 1610.
Persian silk brocade. Persian textile (The Golden Yarns of Zari - brocade). Silk brocade with golden thread (Golabetoon). Pattern and design: Paisley left and right, with main repeating motif
**Textile arts** are arts and crafts that use plant, animal or synthetic fibres to construct practical or decorative objects.

Textiles have been used since the beginning of civilization. Many methods and materials used to make them, but the functions of textiles have stayed the same. 

The history of textile arts is also the history of international trade. Tyrian purple ("imperial purple") dye was important in the ancient Mediterranean. The Silk Road brought Chinese silk to India, North Africa, and Europe. In many countries, laws controlled who could buy and wear fine textiles. This was because they were a symbol of social class and status.

The Industrial Revolution started a revolution of textiles technology: the cotton gin, the spinning jenny, and the power loom mechanized production. The mechanisation of hand work was opposed by the Luddite rebellion.
**Reinforcement learning (RL)** is teaching a *software agent* how to behave in an environment by telling it how well it's doing. It is an area of machine learning inspired by behaviorist psychology.

Reinforcement learning is different from supervised learning because the correct inputs and outputs are never shown. Also, reinforcement learning usually learns as it goes (online learning) unlike supervised learning. This means an agent has to choose between exploring and sticking with what it knows best.

Introduction
------------

369x369px[*permanent dead link*]
A reinforcement learning system is made of a *policy* ({\displaystyle \pi }), a *reward function* ({\displaystyle R}), a *value function* ({\displaystyle v}), and an optional *model* of the environment.

A *policy* tells the agent what to do in a certain situation. It can be a simple table of rules, or a complicated search for the correct action. Policies can even be stochastic, which means instead of rules the policy assigns *probabilities* to each action. A policy by itself can make an agent do things, but it can't learn on its own.

A *reward function* defines the goal for an agent. It takes in a state (or a state and the action taken at that state) and gives back a number called the *reward*, which tells the agent how good it is to be in that state. The agent's job is to get the biggest amount of reward it possibly can in the long run. If an action yields a low reward, the agent will probably take a better action in the future. Biology uses reward signals like pleasure or pain to make sure organisms stay alive to reproduce. Reward signals can also be stochastic, like a slot machine at a casino, where sometimes they pay and sometimes they don't.

A *value function* tells an agent how much reward it will get following a policy {\displaystyle \pi } starting from state {\displaystyle s}. It represents how *desirable* it is to be in a certain state. Since the value function isn't given to the agent directly, it needs to come up with a good guess or estimate based on the reward it's gotten so far. Value function estimation is the most important part of most reinforcement learning algorithms.

A *model* is the agent's mental copy of the environment. It's used to *plan* future actions.

Knowing this, we can talk about the main loop for a reinforcement learning episode. The agent interacts with the environment in *discrete time steps*. Think of it like the "tick-tock" of a clock. With discrete time, things only happen during the "ticks" and the "tocks", and not in between. At each time {\displaystyle t=0,1,2,3,...}, the agent observes the environment's state {\displaystyle S\_{t}} and picks an action {\displaystyle A\_{t}} based on a policy {\displaystyle \pi }. The next time step, the agent receives a reward signal {\displaystyle R\_{t+1}} and a new observation {\displaystyle S\_{t+1}}. The value function {\displaystyle v(S\_{t})} is updated using the reward. This continues until a terminal state {\displaystyle S\_{T}} is reached.

Related pages
-------------

The biology behind Reinforcement learning can be found at:

* Operant conditioning
* Reward
**Petr Eben** (Žamberk, 22 January 1929; died Prague 24 October 2007) was a Czech composer and organist. Many musicians think of him as the most important Czech composer of the late 20th century. He was known world wide for his organ playing. He was especially good at improvisation.

His Life
--------

Eben grew up in Český Krumlov in south Bohemia. He learned to play the piano, and later the cello and organ. Because his father was a Jew he had to leave school in 1943 and spent the rest of the war years in concentration camp in Buchenwald. In the camp he saw many terrible things, including graves into which the Nazis were throwing lots of murdered Jews. These terrible things influenced his music in later years. He had a strong faith and this helped him to survive during 40 years of living in Czechoslovakia under communist rule.

After the war he went to Prague Academy for Music where he studied the piano with František Rauch and composition with Pavel Bořkovec. In 1955 he got a job as lecturer at Charles University in Prague. He stayed there until 1990. He was the country’s best composer, and he should have had promotion, but the communist politicians did not allow this. He went to church every Sunday with his family. This did not help his career in a communist state.

After the Velvet Revolution in 1989, when his country became free from the Soviet Union, he started to become a national hero. He was made Professor of Composition and president of the Prague Spring Music Festival. Many music festivals performed his compositions, and he traveled to hear the concerts in spite of the fact that he was starting to become ill. His music was often played in England, where he had spent two years as professor of composition at the Royal Northern College of Music in Manchester from 1978 to 1979. In March 2007 the BBC Symphony Orchestra under their Czech conductor Jiří Bělohlávek performed his *Vox Clamantis*, a work he had written in 1968 which shows the Czech people’s longing to be free.

His compositions
----------------

Eben continued during his lifetime to develop the style of music in which he wrote. He was interested in Czech folk music and he wrote down many folk songs that he heard in Moravia. He listened to plainchant in church music. All this helped him to develop his own style of composition. He is best-known abroad for his organ music, especially works such as *Musica Dominicalis* (*Sunday Music*) which includes a popular piece called *Moto Ostinato*. Other organ works include *Faust* (1980), *Job* (1987) and *A Festive Voluntary* which is a set of variations on the tune of *Good King Wenceslas*, written for the reopening in 1986 of the organ at Chichester Cathedral which had just been restored. He also wrote a lot of music for orchestra as well as chamber music. He composed some beautiful music for children’s choir, including church music called *Liturgical Songs*.
Remains of the Oppidum at d'Entremont 1
An **oppidum** (plural: *oppida*) is a large fortified Iron Age settlement. 

In the 2nd and 1st centuries BC, they were in all parts of Europe. They continued until the Romans conquered Southern and Western Europe. In Germania, north of the rivers Danube and Rhine, oppida were used into the 1st century AD.

Julius Caesar called the larger Celtic Iron Age settlements he found in Gaul *oppida*. The word is now used to describe the large pre-Roman towns that existed across Western and Central Europe. Many oppida grew from hill forts, but not all of them had an important defensive role. The main features of the oppida are:

* the planned building of the walls and gates
* the spacious layout
* a view of the surrounding area.

The development of oppida was an important step in the urbanisation of Europe. They were the first large settlements north of the Mediterranean that could be described as towns. Caesar pointed out that each tribe of Gaul would have several oppida, but that they were not all of equal importance. This suggests that there was some form of hierarchy.

In conquered lands, the Romans took over the oppida to administer the Empire, and many became full Roman towns. This often involved a change of location from the hilltop into the plain.

One of the best preserved oppida is at Enserune in France. It was occupied continuously from 6th century BC until the 1st century. Other oppida are now buried beneath large cities, such as Vindobona which is covered by Vienna.
The Gatehouse, as seen from the Old Court.
**Queens' College** is one of the colleges that make up the University of Cambridge in England. It was first founded in 1448 by Margaret of Anjou (the Queen of Henry VI), and refounded in 1465 by Elizabeth Woodville (the Queen of Edward IV). This is why the name of the college is spelt Queens' and not Queen's: it was founded by two queens. 

The *President's Lodge* of Queens' is the oldest building on the river at Cambridge, dating from about 1460.

The college is on both sides of the river Cam. A bridge joins the two parts. This bridge is always called the "Mathematical Bridge". The students call the older part of the college "The Dark Side" and the newer part "The Light Side".

Many people take photographs of the college. There is a story that the bridge was designed and built by Sir Isaac Newton without the use of nuts or bolts. The story says that once some students tried to take the bridge apart and put it back together again, but were unable to do so. That is why they had to put nuts and bolts in which can be seen today. The story is not true. The bridge was built in 1749, after Newton had died. It was never taken apart although it was rebuilt twice.

Stephen Fry is one of many famous people who have studied there.

Other websites
--------------

* Queens' College website

| * v
* t
* e
Colleges of the University of Cambridge |
| --- |
| Christ's • Churchill • Clare • Clare Hall • Corpus Christi • Darwin • Downing • Emmanuel • Fitzwilliam • Girton • Gonville and Caius • Homerton • Huges Hall • Jesus • King's • Lucy Cavendish • Magdalene • Murray Edwards • Newnham • Pembroke • Peterhouse • Queens' • Robinson • St Catharine's • St Edmund's • St John's • Selwyn • Sidney Sussex • Trinity • Trinity Hall • Wolfson |
Visual pathway with optic chiasm (X shape outlined, red. Brain seen from underneath.
Scheme showing central connections of the optic nerves and optic tracts.
The **optic chiasma**, or 'optic chiasm', is the part of the brain where the optic nerves (CN II) partially cross. The optic chiasm is located at the bottom of the brain immediately below the hypothalamus.

Pathways
--------

The images on the nasal (inner) sides of each retina cross over to the opposite side of the brain via the optic nerve at the optic chiasm. The temporal (outer) images, on the other hand, stay on the same side. This allows the images from either side of the visual field to go to the appropriate side of the brain, combining the sides together.

Beyond the optic chiasm, with crossed and uncrossed fibers, optic nerves become optic tracts.

The crossing over of optic nerve fibres at the optic chiasma allows the visual cortex to receive the same hemispheric visual field from both eyes.

The optic chiasma is found in all vertebrates.
***Nyasasaurus*** ("Lake Nyasa lizard") is an extinct genus of Archosaur reptile from the Middle Triassic Manda Beds of Tanzania. It may be the earliest known dinosaur. The discovery was a handful of bones from two individuals, so its anatomy is only partly known. The bones were collected in the early 1930s, but have only recently been analysed.

Researchers said: "*Nyasasaurus* possesses a unique combination of dinosaur character states and an elevated growth rate similar to that of definitive early dinosaurs. It demonstrates that the initial dinosaur radiation occurred over a longer timescale than previously thought (possibly 15 million years earlier)".

The find was six vertebrae and a humerus from one specimen, and five vertebrae from another. The humerus has a muscle attachment which is characteristic of dinosaurs (a long 'deltopectoral crest'). Other features are consistent with its being a basal dinosaur.

Previously, the oldest record of dinosaurs was from Argentina and dated back to the Upper Triassic Carnian stage, about 231.4 million years ago (mya). *Nyasasaurus* comes from a deposit that dates back to the Middle Triassic Anisian stage, meaning that it predates other early dinosaurs by about 15 million years.
Heraldic depiction of a duke's coronet, with blue bonnet of a peer
Coronet and mantle of a duke and peer of France, shown here with the collars of the *Ordres du roi*
The **Peerage of France** (French: *Pairie de France*) the exclusive prestigious title and position of Peer of France was held by the greatest, highest-ranking members of the French nobility, was a hereditary distinction within the French nobility which appeared in 1180 in the Middle Ages, and only a small number of noble individuals were peers. The title of 'Peer of France' was an extraordinary honour granted only to a small number of princes, dukes, counts of the Roman Catholic Church.

French peerage thus differed from British peerage (to whom the term "baronage", also employed as the title of the lowest noble rank, was applied in its generic sense), for the vast majority of French nobles, from baron to duke, were not peers. It was analogous to the rank of Grandee of Spain in this respect.
It was abolished in 1789 during the French Revolution.

Bibliography
------------

* Richard A. Jackson, "Peers of France and Princes of the Blood", *French Historical Studies*, volume 7, number 1 (Spring 1971), pp. 27–46
* *La Chanson de Roland*, edited and translated by Ian Short, Paris: *Livre de Poche*, 1990, ISBN 978-2-253-05341-5
A drawing of a spleen
The **spleen** is an organ in vertebrates. The spleen is part of the lymphatic system. In people, it is on the left side of the body, under the heart. The spleen helps fight infections and keeps the blood cells healthy.

Tasks
-----

The spleen cleans out old blood cells from the blood and recycles them. It helps save the iron and the amino acids from the old blood cells. The spleen also holds a supply of extra blood, in case the body needs some quickly. The spleen works together with the circulatory system (the system which brings blood to the body).

A study published in 2009 using mice found that the spleen is a reservoir which holds over half the body's monocytes. These monocytes move to injured tissue (such as the heart after myocardial infarction), turn into dendritic cells and macrophages, and promote tissue healing. The spleen is rather like a large lymph node. Its absence makes certain infections more likely.

Shape
-----

The spleen is shaped like a loose fist. It is tucked under the left side of the diaphragm, close by the heart.The average adult spleen weighs 0.44 lbs.

Disease
-------

The spleen can get bigger when a person is digesting food or is sick. If a person's spleen gets big enough, it can break open. If this happens, the person needs medical care right away. Emergency surgery might be needed to control the bleeding.

Some of the diseases that cause the spleen to get bigger are: 

* malaria,
* rheumatoid arthritis,
* systemic lupus,
* sickle cell anemia,
* leukemia,
* lymphoma, and
* mononucleosis ("mono").

Culture
-------

In the past, many people believed the spleen helped control emotions. For example, if a person was upset or angry, people would think it was because of a spleen problem.
**Quotient space** is a term from linear algebra. It is a vector space that is made using a vector subspace, and a parallel projection. The elements of quotient spaces are equivalence classes. 

A simple example of a quotient space is the following: take the Cartesian coordinate system and draw a straight line which goes through the origin of that system. All the lines which are parallel to that line are a quotient space.

More detailed description
-------------------------

In linear algebra, the **quotient space** of a vector space V by a subspace N, also said V/N, is the set of vectors v and w of V such that v-w is in N. We can also say that v added by any vector of N is in the class of v, also called [v]. The set of v and vectors in V such that v plus all those vectors are in N are written V/N (V/N = {v + N | v ∈ V }).

Also, two vectors of V are equivalent if their substraction are in W.

The quotient space shares this two propierties:

* α[*x*] = [α*x*] for all α ∈ *K*, and
* [*x*] + [*y*] = [*x* + *y*].

Also, dim(V /W) = dim V − dim W. 

We will construct an explicit basis for V/W. Let (w1,. .. , wn) be a basis of W, and extend it to a basis (w1,. .. , wn, v1,. .. , vk) of V. Note that with this notation, dim W = n and dim V = n + k. We claim that (v1 + W,. .. , vk + W) forms a basis of V /W, in other words, ([v1], [v2],. .. , [vk]).

If so, we will then have dim(V /W) = k = (n + k) − n = dim V − dim W as claimed.
The Nazi German Occupation of Czechoslovakia started on the 15th of March 1939 when German troops entered the region of Bohemia and Moravia, having already had the Sudetenland thanks to the Munich Agreement. The region of Bohemia and Moravia was annexed into the German reich and a puppet government was established under rule of Konstantin von Neurath, who was later replaced by Reinhard Heydrich in 1939 as he was seen too soft on the Czechs. The Czech Government in exile sent two paratroopers to assassinate the Reichsprotektor, Reinhard Heydrich. The operation was code named Operation Anthropoid. The assassins were equipped with a Sten gun and a Impact grenade. The two paratroopers were Jozef Gabčík and Jan Kubiš they planned on assassinating him when he was in his car on a road where the car had to slow down. When they reached the road, Jozef Gabčík, equipped with the Sten gun, opened fire, but the Sten gun jammed, so Kubiš threw his grenade which seriously wounded the Reichsprotektor. it is said that Heinrich refused help of a Jewish doctor. He died a few days later. The occupation ended when the Soviet troops entered Prague and liberated the rest of the Republic until 1945 when the Soviet Union invaded it and turned Czechoslovakia into a Communist State in 1948 .
A artists impression of what a ocean world with two moons may look like.
An **ocean planet** (or **ocean world**, **water world**, **aquaplanet** or **panthalassic planet**) is a type of terrestrial planet that contains a high amount of water. This may be a planet with ocean covering all of its surface (except maybe at the polar regions, where ice caps may exist), or a planet with a ocean bellow its surface (called a subsurface ocean). 

Ocean planets are also the name of planets that have other types of liquids on them such as liquid ammonia, ethane, or even lava.

Habitation
----------

A ocean planet covered in water may have conditions to support life. This has been questioned though, since some studies suggest that water worlds may not be friendly to life, since elements like phosphorus (a key part to DNA) may be hard to access, since it any be hidden in rocks at the bottom of the planet's oceans. Other problems here may be certain parts of the water cycle not working on an ocean planet, or the low amount of oxygen in the atmosphere. With that being said, there are still possibilities for life on water planets.

Possible ocean worlds
---------------------

Kepler-22b is a possible ocean world.
There are a few planets that could be ocean planets. All of these are extrasolar planets. 

* Kepler-22b a rocky super-Earth that lies in the habitable zone of its host star.
* Gliese 1214b a super Earth that circles its red dwarf star very close, but a deep ocean may exist under high pressure caused by a strong atmosphere.
* Kepler-62e, a rocky Earth-like planet that may be a warm and humid planet.
* At least one of the TRAPPIST-1 planets may be an ocean world. The TRAPPIST-1 system is home to at least seven Earth-sized planets.

Several of the moons in the solar system may have oceans bellow their surfaces, which would make them ocean moons. One such example is Europa, one of Jupiter's moons.
**Occidental College** is a small college in Los Angeles, California. Several famous people, such as Barack Obama, have attended the college. Its name comes from the Latin for "western".

The college was started in 1887 and moved to where it is now in 1914. Many of its early buildings were designed by Myron Hunt. After World War II, Oxy became known both for being a very good school and for student protests. Its current president is Jonathan Veitch.

The school has 1,825 students. The school is 60% female and 40% male.

All Occidental students must take a "Core Program" that includes classes in writing, the arts, humanities, foreign languages, math and science. Occidental is known for student research projects. Many of Occidental's students study at the United Nations, in Washington, DC, and in other countries.

Occidental has Division III sports teams in 19 sports, including football, basketball, baseball and soccer.

Famous students include Barack Obama (for two years), Ben Affleck, Luke Wilson, Jack Kemp, and Patt Morrison.

Occidental has been in many movies, including *Fired Up*, *Star Trek III*, and *Beverly Hills, 90210*. It has also appeared in hundreds of advertisements.
**Notre Dame Stadium** is the home football stadium for the University of Notre Dame. The university's football team are the Fighting Irish. The stadium is located on the university's campus in Notre Dame, Indiana, just north of the city of South Bend. It was opened in 1930. The stadium can seat over 80,000 people.

History
-------

The stadium opened in 1930. It replaced the old stadium Cartier Field. It cost more than US$750,000 to build. The head coach of the Fighting Irish, Knute Rockne, played an important role in the design of the stadium. The design was based on Michigan Stadium. The stadium originally held 54,000 people. It measured a half-mile (0.8 kilometres) in circumference and stood 45 feet (14 m) high. It was built by the Sollitt Construction Company of South Bend. They began building in April 1930, and took six months to build. The Irish played their first game in the new stadium on 4 October 1930. They beat the SMU Mustangs 20–14. The official dedication was on October 11 against Navy.

Over the years, the stadium's seating capacity was gradually increased to 59,075. This was mainly done by making most of the seats smaller. In 1997, 21,000 new seats were added to the stadium, bringing the seating capacity to the present 80,795. Permanent lights were also installed. The lights were paid for by NBC, which has held the exclusive television rights to all home games since 1991.

The playing surface was natural grass throughout the stadium's history until FieldTurf, an advanced artificial surface, was installed before the 2014 football season.

*Touchdown Jesus*
-----------------

*Touchdown Jesus*
The stadium is known for its view of *Touchdown Jesus* (actually titled *The Word of Life*), a large mural of the resurrected Jesus. The mural is painted on the southern exterior wall of the Hesburgh Library. It is 132 ft (40 m) high and 65 ft (20 m) wide. It can be seen over the northern end zone of the stadium. The mural was designed by Millard Sheets and was constructed in 1964. It cost US$200,000. It is contains 81 types of stone from 16 countries, and is composed of hundreds of panels which incorporate 6,700 pieces of granite.

In 1997, fans protested the university's plans to add 20,000 seats to the stadium. These seats would have blocked the view of *Touchdown Jesus* from the field. The university then considered limiting seats in the end zone. For aesthetic reasons however, developers went with a larger bowl all the way around. As a result, the view of *Touchdown Jesus* was partially blocked.

Other websites
--------------

* Notre Dame Stadium Archived 2009-02-26 at the Wayback Machine
**Suncheon** is a city in South Korea. It belongs to Jeollanam-do. 70% of Suncheon is composed of mountains and the city has the greatest number of mountains in the province. The average temperature for the year is 12.5℃. The average temperature in January is -0.5℃ and the average temperature in August is 25.2℃. Since Suncheon fronts the southern sea, the city is relatively warm during the winter by the effect of oceanic climate.

Suncheon is famous among Korean travelers due to its beautiful tourist attractions and local food of great taste. Among many spots, Suncheon bay is the most well-known. It was selected as one of the top 5 coastal wetlands in the world. The large mud flat stretches out and several kinds of birds and other living creatures live there. Also, the wide field of reeds along the waterside forms magnificent view. The Suncheon bay reeds festival is held every October and it gets great reputation.

Since the city is located near to the sea, dishes made of diverse fresh fish highly attract those who visit Suncheon. Especially, thanks to the well-protected ecological environment, mudskippers which exist usually in the very clean mud flat are seen in the Suncheon bay. They are used for cooking in Suncheon and the dish is very famous for its greater taste than any other region in the country.
The Murchison meteorite
The **Murchison** meteorite is named after the place it fell: Murchison, Victoria, Australia. It is large (over 100 kg) and it was seen falling. It is one of the most studied meteorites, since it belongs to a group of meteorites rich in organic compounds, known as carbonaceous chondrites.

On 28 September 1969 at about 10:58 am, a bright fireball was seen. It separated into three fragments before disappearing, leaving a cloud of smoke. About 30 seconds later, a tremor was heard. People found fragments over an area larger than 13 km², with fragments up to 7 kg. One, weighing 680 g, broke through a roof and fell in hay. The mass is over 100 kg.

The biochemistry
----------------

This type of meteorite is rich in carbon. Murchison contains over 15 amino acids. The amino acids found in the Murchison meteorite can be (and have been) synthesised in laboratory experiments. This was done by the action of electric discharge on a mixture of methane, nitrogen, and water with traces of ammonia.

The amino acids were mostly racemic. This means the chirality of their enantiomers are almost equally left- and right-handed. This suggests they are not caused by terrestrial contamination. A complex mixture of alkanes was isolated as well, similar to that found in the Miller-Urey experiment. Serine and threonine, often earthly contaminants, were absent from the samples.

In 1997 research showed that individual amino-acids from Murchison were enriched in the nitrogen isotope 15N relative to their terrestrial counterparts. This confirmed an extraterrestrial source. The organic materials identified included sugar-like compounds (polyols).

| **Compound class** | **Concentration (ppm)** |
| --- | --- |
| Amino acids | 17-60 |
| Aliphatic hydrocarbons | >35 |
| Aromatic hydrocarbons | 3319 |
| Fullerenes | >100 |
| Carboxylic acids | >300 |
| Hydrocarboxylic acids | 15 |
| Purines and pyrimidines | 1.3 |
| Alcohols | 11 |
| Sulphonic acids | 68 |
| Phosphonic acids | 2 |

Several lines of evidence show that the inside of well-preserved fragments from Murchison are pristine (not contaminated). A 2010 study identified 14,000 molecular compounds (including 70 amino acids) in a sample of the meteorite. There may be 50,000 or more different molecular compositions in the meteorite.

### Nucleobases

Measured purine and pyrimidine compounds are in the Murchison meteorite. Carbon isotope ratios for uracil and xanthine show a non-terrestrial origin for these compounds. The results show many organic compounds which are components of life on Earth were already present in the early Solar System. They may have played a role in life's origin.
"**Raise Your Weapon**" is a song by Canadian electronic music producer deadmau5 and features vocals from Greta Svabo Bech. The song is featured on deadmau5's fifth studio album *4×4=12.*

The song starts with a piano melody played in 4/4 time under the vocals and enters then the song enters a dubstep bassline about halfway through the song with the vocals from the beginning repeat.

The song received positive reviews from critics with David Jeffries from Allmusic saying "When the one-two punch of "Raise Your Weapon" and "One Trick Pony" introduce the Mau5’s newfound love of dubstep, you’ve got just enough variety." and Will Hermes of Rolling Stone saying "The masterstroke is "Raise Your Weapon," which breaks down into a sick dubstep beat. "How does it feel now, to watch it burn?" asks singer Greta Svabo Bech before the bass hits".

"Raise Your Weapon" was nominated for Best Dance Recording at the 54th Grammy Awards. deadmau5 also performed the song in a sequence with David Guetta, Chris Brown, Lil Wayne and Foo Fighters, with the songs being "I Can Only Imagine" by Guetta, Brown, and Wayne and "Rope" by The Foo Fighters.
A **spitting spider** is a spider in the family ***Scytodidae***. There are more than 150 species of spitting spider in the world. Spitting spiders are related to the recluse spiders in the *Sicariidae* family.

The name *spitting spider* comes from the way these spiders hunt. The spider spits a sticky and poisonous liquid at its prey. The liquid congeals (becomes solid) around the target. When the prey is trapped, the spider bites it to kill it with venom. It then wraps the prey in spider silk like many other spiders do.

A spitting spider attack is very fast. It takes about 1/700th of a second. This kind of spider can spit 10 to 20 millimetres (0.39 to 0.79 in). The spider spits in a Z pattern and criss-crosses its prey in sticky liquid.

There are five genera of spitting spiders:

* *Dictis* (China to Australia)
* *Scyloxes* (Kyrgyzstan)
* *Scytodes* (worldwide)
* *Soeuria* (Seychelles)
* *Stedocys* (Malaysia, Thailand)

Sources
-------

1. ↑  Gilbert, C. and L. S. Rayor. 1985. Predatory behavior of spitting spiders (Araneae, Scytodidae) and the evolution of prey wrapping. J. Arachnol. 13 :231-241
2. ↑  Piper, Ross (2007), Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals, Greenwood Press.

Wikispecies has information on: ***Scytodidae***.

Wikimedia Commons has media related to ***Scytodidae***.
**Octavia E. Butler** was an American science fiction writer. She won many awards. She won the Hugo and Nebula awards more than once. She won the MacArthur Fellowship in 1995.

Early life
----------

Butler was born in Pasadena, California on June 22, 1947. She lost her father at a young age. Butler was raised by her mother, who worked as a maid. Butler started creating her own stories early on. Butler was dyslexic but she didn't let it challenge her from developing a love of books. She decided to make writing her life's work at the age of ten. As a child Butler was known for her shyness and her impressive height. She attended many colleges. She earned her associates degree at Pasadena City College. She also went to California State University, and University of California at Los Angeles.

Public life
-----------

Butler studied fiction with Harlan Ellison and became an author of books for both children and adults. She was a very good science fiction writer. Important books she wrote were Pattermaster and Mind of My Mind. She won the 1984 Best Short Story for "Speech of Sounds," and she won the Nebula Award. Octavia was known for African American Spiritrualism.

Death
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Butler died at her home of a stroke in Seattle, Washington on February 24, 2006.
The **nyala** (*Nyala angasii* or *Tragelaphus angasii*), also called **inyala**, is an antelope that lives in southern Africa. It has the highest sexual dimorphism among other spiral-horned antelopes.

The nyala is mainly active early in the morning and late in the afternoon. As a herbivore, the nyala eats leaves, fruits and grasses. They prefer water holes rather than open spaces. The nyala is not a territorial animal. Family groups of up to 10 individuals can be found. Old males live alone but family groups of up to ten members live in thickets within dense and dry savanna woodlands. The main predators of the nyala are lion, leopard and Cape hunting dog, while baboons and raptors hunt for the young. Mating peaks during spring and autumn.

Nyalas live in Malawi, Mozambique, South Africa, Swaziland and Zimbabwe. They have been introduced to Botswana and Namibia, and reintroduced to Swaziland, where they became extinct in the 1950s. Populations are stable and are of Least Concern by the International Union for Conservation of Nature (IUCN). The main threats to the species are poaching and habitat loss resulting from human settlement. The males are highly demanded as game animals in Africa.
**Louis of France** (16 August 1682 – 18 February 1712) was the eldest son of Louis, Dauphin of France, known as *le Grand Dauphin* and, as such, was known as *le Petit Dauphin*. He became Dauphin of France upon his father's death in 1711.

Biography
---------

Arms as Duke of BurgundyArms as Duke of Burgundy
Arms as DauphinArms as Dauphin
*Éléments de géométrie*, 1713
**Louis de France** was born in the Palace of Versailles, the eldest son of Louis, *le Grand Dauphin*, and his wife Maria Anna Victoria of Bavaria. At birth, he received the title of Duke of Burgundy.

Louis grew up with his younger brothers; Philippe, Duke of Anjou and Charles, Duke of Berry. 

At the age of 15, he married his second cousin, Marie Adélaïde of Savoy, the daughter of Victor Amadeus II, Duke of Savoy and Anne Marie d'Orléans. This match had been decided as part of the Treaty of Turin, which ended Franco-Savoyard conflicts during the Nine Years' War. The marriage took place on 7 December 1697 at the Palace of Versailles. The two were in love with one another, a rarity at the court of Versailles.

Louis became Dauphin of France upon the death of his father in 1711. 

In February 1712, his wife contracted measles and died on the 12th of that month. 

The Duke of Burgundy, who dearly loved his wife and who had stayed by her side throughout the fatal illness, contracted the disease and died on 18 February, six days after her at the Château de Marly. Both of his sons also became infected, the eldest, Louis, Duke of Brittany, the latest in a series of Dauphins, succumbed to it on 8 March. The only one to survive was the two-year old Duke of Anjou, the future King Louis XV of France.

Children
--------

1. **Louis of France, Duke of Brittany** (25 June 1704 – 13 April 1705) died of convulsions;
2. **Louis of France, Duke of Brittany** (8 January 1707 – 8 March 1712) died of measles;
3. **Louis XV of France** (15 February 1710 – 10 May 1774) first engaged to Mariana Victoria of Spain; married Marie Leszczyńska and had issue; died of smallpox.

Titles, styles, honours and arms
--------------------------------

### Titles and styles

* **16 August 1682 – 14 April 1711** *His Royal Highness* The Duke of Burgundy
* **14 April 1711 – 18 February 1712** *His Royal Highness* The Dauphin of France

Other websites
--------------

 Media related to Louis, Duke of Burgundy at Wikimedia Commons
A **system of units** is a collection of units of measurement. The quantities described by the units are related to each other by specific rules. These rules may not contradict each other. An example of a system like this is one needed for the problems of the economic system.

Base and derived units
----------------------

Some of the units are called "base units". These units can be defined by arbitrarily. Other units are called derived units. They are defined using the base units. 
The most common systems of units today are the International System of Units (SI), the Imperial units and the United States customary units. 

The base units of SI are the metre, the second, the kilogram, the ampere, the kelvin, the candela and the mole. SI has many derived units which include the watt, newton and joule. SI is called a "coherent system of units" because the constant factor in the definition of it derived units is always 1.

The base units of the imperial system and the United States customary system are the pound avoirdupois, the yard and the second. Derived units found in the Imperial and Customary systems of units include horsepower and Pounds per square inch.

Coherent units
--------------

The relationship force, energy and power is an example of coherence. The equations are

*force = kf × mass × acceleration*
*energy = ke × force × distance*
*power = kp × energy / time*.
If kf = 1 and ke = 1 and kp = 1 then the relationships are coherent.

  

In SI, the equations become

*newtons = kilograms × metres per second squared*
*joules = newtons × metres*
*watts = joules / second*.
SI is therefore a coherent system.

  

In the cgs system of units, the equations become

*dynes = grams × centimetres per second squared*
*ergs = dynes × centimetres*
*ergs per second = erg / second*.
The equations for the cgs system do not have any additional constants. It is therefore a coherent system.

  

In the MKS-gravitational system, the equations become

*kilogram-force = kilograms × metres per second squared / 9.80665*
*Pferdestärke = 75 × kilogram-force × metres /seconds*
The equations in the MKS-gravitational system have factors 75 and 9.80655. The system is therefore not is therefore not a coherent.

Related pages
-------------

* System of measurement
Max Reger
**Max Reger** (born in Brand, Bavaria, 19 March 1873; died 11 May 1916) was a German composer, organist, pianist and teacher.

Life
----

Reger’s father was a schoolteacher who was an amateur musician. When he was a boy Max helped his father to rebuild an organ that was going to be thrown away. This was the instrument on which he learned to play. It was some time before he started proper lessons, but by the time he was a teenager he was playing the organ for church services. When he was 15 he went to Bayreuth to hear Wagner’s operas. This was the moment when Reger decided he wanted to become a musician.

Reger studied music in Munich and Wiesbaden with a famous teacher Hugo Riemann. He composed a lot of music, especially for the organ. His musical style was similar to that of Brahms, but he also learned a lot from the music of Bach, Mendelssohn and Schumann. He liked the symphonic poems of Liszt and these gave him the ideas for writing chorale fantasies for the organ, although he never wrote music that tells a story (programme music).

In 1902 Reger married. He and his wife adopted two children. In 1907 he became professor of composition at the University of Leipzig. He was a very good teacher. He became well-known abroad. He travelled to London where he spent hours in the art galleries. Then he bored his friends by talking all the time about the paintings. He conducted the orchestra at Meiningen, performing works by many composers, especially Brahms, Bruckner and his own.

Reger enjoyed eating and drinking. He regularly went to his local café where he would eat ten large sausages and drink ten glasses of beer. His health got bad, and he died of a heart attack in Leipzig, where he was visiting friends on his way home from the Netherlands.

Works
-----

Reger wrote an enormous amount of music, but very little of it is played nowadays. He wrote in a late-Romantic style. He is best remembered for his organ music. He liked to write fugues and sets of Variations. His *Fantasy and Fugue on BACH* is one of the hardest pieces ever written for organ. He wrote a lovely song called *Marias Wiegenlied* (*Mary’s lullaby).*
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Site where Sri Maha Bodhi is
The **Sri Maha Bodhi** is a Sacred Fig tree in Anuradhapura, Sri Lanka. The site where it's on, **Sacred City of Anuradhapura**, is part of the UNESCO World Heritage Sites. 

It is said to be a tree grown from a sapling from the famous Bodhi tree where the first Buddha became enlightened. It brought down by Mihindu (Mahinda) and Sanghamitta. It was planted in 288 BC. It is the oldest living human-planted tree in the world with a known planting date. 

It was planted on a high terrace about 6.5 m (21.3 ft) above the ground. It is surrounded by railings to protect it. It is one of the most sacred objects of the Buddhists in Sri Lanka, and respected by Buddhists all over the world. 

Its wall was built during the reign of King Kirthi Sri Rajasingha, to protect it from wild elephants which might have attacked the tree.

History
-------

In the 3rd century BC, the Buddha's fig tree was brought to Sri Lanka by Sangamitta, daughter of Emperor Asoka and founder of an order of Buddhist nuns, in Sri Lanka.

In 280 BC, Jaya Siri Maha Bodhi was planted in the Mahamevnāwa Park in Anuradhapura by King Devanampiya Tissa.

Related pages
-------------

* Bodhi tree

Other websites
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* Living Heritage - Jaya Siri Maha Bodhi  Archived 2011-07-18 at the Wayback Machine
The **sun bear** (*Ursus malayanus* or *Helarctos malayanus*) is a bear living in Southeast Asia.

Appearance
----------

The sun bear is the smallest bear. It has short black fur, and a yellow spot on its chest. Its ears are small and round. It has big feet with naked soles and long claws, which help the sun bear climbing. It can climb very well. It cannot see very well, but its sense of smell is very good.

Life
----

Jaws of sun bear
Sun bears mostly live in tropic rainforests. They are mostly active at night, and they stay in trees a lot of the time.

It eats a lot of different things: fruit and other plants, eggs, honey and insects. They also eat small vertebrate animals, like reptiles, birds and mammals.

After a pregnancy of 96 days the female gives birth to 1-2 babies. Young sun bears become mature when they are 3-4 years old. sun bears can become up to 28 years old when in captivity (held by humans, e.g. in zoos).

Sun bears do not hibernate.

Other websites
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* Sun bear by BearPlanet


Wikimedia Commons has media related to ***Ursus malayanus***.