AcharyaChanakya/simple-wikipedia huggingface dataset:
Mozart's operas are among his greatest works. He understood people's characters very well and was able to write music which tells us everything about the personalities in the operas. The three operas in which he set words by Lorenzo Da Ponte: "Don Giovanni", "Le Nozze di Figaro" ("The Marriage of Figaro") and "Cosi fan tutte" each include some very clever ensembles in which several characters are singing at once, each one showing his or her view of the situation.
As well as many great masterpieces, Mozart wrote many pieces in a more popular style, including some tunes that everybody knows today. His serenade "Eine kleine Nachtmusik K525" is known everywhere, as is the "Turkish Rondo" from his "Piano Sonata in A K331", the opening of the "Symphony No. 40 in G minor K550", and the birdcatcher’s song from "The Magic Flute K620."
Some time after Mozart’s death a man called Köchel studied all Mozart’s music, tried to put them in chronological order, and gave them a number. The number helps us to know exactly which work is meant, for example "Symphony in G minor K183" is not the same piece as "Symphony in G minor K550" (K stands for Köchel. Sometimes it is written "KV550" standing for "Köchel Verzeichnis" i.e. "Köchel Catalogue"). The highest Köchel number is 626, his requiem mass.
Johann Sebastian Bach (31 March 1685 in Eisenach – 28 July 1750 in Leipzig; pronounced "BAHK") was a German composer and organist. He lived in the last part of the Baroque period. He is most famous for his work "Toccata and Fugue in D Minor", "St. Matthew Passion", "St. John Passion", "Mass in B minor", and the "Brandenburg Concertos". He spent several years working at courts of noblemen. Here he wrote most of his chamber music and orchestral music. Most of his life, however, he worked in a church where he was expected to write church music. Bach wrote almost every kind of music except opera. During the last part of his life most composers were writing in a new style called the Classical style, but Bach always wrote in the Baroque style. That made some people at the time think he was old-fashioned, but today we know that his work is the very best of Baroque music. Along with Mozart and Beethoven, Bach is regarded as one of the greatest composers who has ever lived.
Bach came from a highly musical family. His father, Johann Ambrosius Bach, was a trumpeter at the court of Saxe-Eisenach. Many of his relatives were professional musicians of some sort: violinists and town musicians, organists, "Cantors" (Directors of Music in a church), court musicians and "Kapellmeisters" (Directors of Music at a royal court). Most of them played several instruments. Of his twenty children, several became quite famous composers, especially Carl Philipp Emanuel Bach (1714–1788), Johann Christian Bach (1735–1782), Johann Christoph Friedrich Bach and Wilhelm Friedemann Bach (1710–1784).
When he was fifteen, he went to the small town of Lüneburg. At first he sang treble in the choir and was said to have a very fine treble voice, but his voice very soon got lower, so he made himself useful playing instruments. He learned by listening to famous organists like Reincken (1623–1722) and Dietrich Buxtehude (1637–1707). Bach got his first job in 1703 in Arnstadt. It was a well-paid job for a young boy who was 18 years old. There was a new organ in the church, and Bach already knew a lot about organ building as well as being a brilliant organist. They asked him to examine the new organ, and then they offered him a job. Bach spent four years as organist there. He composed some organ works. Unfortunately, the congregation were not musical enough to like it. They did not understand the ornamental notes he added to the hymn tunes. Bach got rather fed up with the priests who were always complaining about it, so he resigned and took another job in Mühlhausen, not far away. After a year there, he gave up that job and went to a big town called Weimar.
Johann Sebastian was made organist to the Duke of Saxe-Weimar. At the Duke’s court there was a chapel with an organ. Bach composed many of his great organ works at this time. He became very famous as an organist and was invited to play in other big churches and to give advice on organ building. He was extremely good at improvisation. On one occasion he was in Dresden at the same time as a French organist named Louis Marchant. There was going to be a competition between the two men to see who was better at improvisation. Bach was practicing the day before and Marchant heard him. He realized that Bach would win, so he left.
In 1714 the Duke made Bach "Konzertmeister" (Concertmaster, a job that paid more money.) He had to write cantatas for church services. In 1717 he was offered a job in the town of Cöthen, where he would earn an even better salary. The Duke was angry and did not want him to go but Bach insisted, so the Duke put Bach in prison for a month. In the end he had to let the musician go.
At Cöthen, Bach worked for Prince Leopold. The Prince was very musical and a wonderful man to work for. Bach was "Kapellmeister" (Director of Music) and was treated well. The organ was not very good, and it was not used much, so Bach did not write any organ music during this period. The Duke had an orchestra, and Bach was in charge. Nearly all Bach’s orchestral works were written in Cöthen: the Brandenburg Concertos, the violin concertos, the orchestral suites, the solo music for violin and for cello, and a lot of keyboard music for harpsichord or clavichord.
During 1719, the great composer George Frideric Handel, who had moved to England, came to Germany to visit his mother. Bach wanted to meet Handel, who was only 30 km away, but these two famous musicians never met. Handel wanted to spend his limited time in Germany with his mother who was old and frail, knowing that it would be the last time he would see her.
Bach’s first wife, Maria Barbara Bach, died in 1720. The couple had seven children. Soon afterwards, he married Anna Magdalena with whom he had another thirteen children. However, several of his children died young.
In 1723 Bach moved to Leipzig to take the job of "Cantor" at the St Thomas Church, a very large church in the town. As "Cantor" he was in charge of all the music, both at St Thomas and at another church nearby. He also had to compose music for the town. It was an excellent job, and more secure than being at a court. The schools were good for his sons. Bach stayed in Leipzig until his death. He loved his job most of the time and worked very hard. He composed many cantatas for the church services. These services were very long, lasting about three hours. Many of the cantatas he wrote last about 30 minutes, and that was just one part of a service! He had assistants to play the organ. Bach himself directed the choir and the orchestra. There were probably 16 singers in the choir and 18 players in the orchestra. He wrote the "St Matthew Passion" and the "St John Passion". Both these works, which are very long, tell the story of Jesus dying on the cross. They are among the most famous pieces of music ever written. He also wrote cantatas for special occasions such as weddings or funerals.
Life was not always easy, and sometimes there were arguments with the people who ruled the church. The sub-deacon wanted to choose some of the hymns, but this was the "Cantor’s" job. Bach was a sensible man, and he managed to get his way without making enemies. On another occasion he argued with the headmaster of the school (Bach had to do some teaching at the church school) about who was allowed to choose the choir section leaders. This actually went to court, and Bach won the case.
Bach often made journeys to other towns. In 1747 he visited the court of Prussian King Frederick the Great near Berlin. The king, a music lover, gave Bach a theme to improvise from on the harpsichord. Bach sat down and improvised a fugue using this theme. Later Bach wrote a very long composition for flute, violin and harpsichord with cello accompaniment, in many movements, all based on this theme. At the end, the theme is heard in 5 of the 6 voices. Bach called it "The Musical Offering" and he sent it to the king.
Bach wrote many fugues, eventually he decided to write a collection called "The Art of Fugue". His plan was to publish it, but he died before he could finish it (his son later published it in his honor, as Bach's last published piece). In the last year or two of his life, he became blind in spite of two eye operations.
In the 19th century more people became interested in Bach, and many of his works were published after he had been dead more than a hundred years.
Atmosphere of Earth
The atmosphere is the layer of gases around the Earth. It is held in place by Earth's gravity.There are total 5 layers of atmosphere, named stratosphere, troposphere,mesosphere,thermosphere and exosphere. It is made up mainly of nitrogen (78.1%). It also has plentiful oxygen (20.9%) and small amounts of argon (0.9%), carbon dioxide (~ 0.035%), water vapor, and other gases. The atmosphere protects life on Earth by absorbing (taking) ultraviolet rays from the sun. It makes our days cooler and our nights warmer.
Solid particulates, including ash, dust, volcanic ash, etc. are small parts of atmosphere. They are important in making clouds and fog.
The atmosphere does not end at a specific place. The higher above the Earth, the thinner the atmosphere. There is no clear border between the atmosphere and outer space, though the Kármán line is sometimes treated as a border. Even higher, for some purposes the edge of the magnetosphere is treated as a border. 75% of the atmosphere is within of the Earth's surface.
Originally, the Earth's atmosphere had almost no free oxygen.
Some parts of the atmosphere are hot or cold, depending on height. Starting from the surface and climbing straight up, the air gets colder in the troposphere, but then it becomes hotter, higher in the stratosphere. These changes of temperature are divided into layers. These are like layers of an onion. The difference between the layers is the way the temperature changes.
These are the layers of the atmosphere, starting from the ground:
Where one layer changes to the next have been named "-pauses." So the tropopause is where the troposphere ends ( high). The stratopause is at the end of the stratosphere. The mesopause is at the end of the mesosphere.
These are called boundaries.
The average temperature of the atmosphere at the surface of Earth is .
The atmosphere has pressure. This is because even though air is a gas, it has weight. The average atmospheric pressure at sea level is about .
The density of air at sea level is about 1.2 kilograms per cubic meter. This density becomes less at higher altitudes at the same rate that pressure becomes less. The total mass of the atmosphere is about 5.1 × 10 kg, which is only a very small part of the Earth's total mass.
Human penis
The human penis is a male body part found on the outside of the body. It is used for urination and for sexual reproduction. The main sexual function of the penis is to be inserted into a female's vagina and deliver semen which may cause pregnancy. This activity is called sexual intercourse.
There are many slang words for "penis". They include "dick", "cock", and "schlong". A euphemism for "penis" is "male member".
The human penis exits the abdomen above the testicles and hangs freely outside the body. The main visible part is called the shaft.
The human penis is made up of three types of tissue. It has two corpora cavernosa (special pieces of muscle) next to each other and a corpus spongiosum (spongy muscle) between them.
The end of the corpus spongiosum forms the glans penis which is underneath the foreskin in uncircumcised males. The area on the bottom of the penis, where the foreskin is attached on uncircumcised men, is known as the frenulum. The urethra, the tube where urine and semen travel through, runs down the corpus spongiosum (spongy tissue), and opens at the tip of the penis. Sperm are made in the testes (ball-like organs) and stored in the epididymis (layer of tissue) around the testes. During ejaculation, sperm are pushed up the vas deferens. Fluids are added by the seminal vesicles, the prostate gland and the bulbourethral glands to make semen.
A penis can become erect if a male is sexually aroused (or sometimes during sleep, even though there is no sexual stimulation). In an erection, the penis fills with blood. The blood makes the penis become longer, thicker and harder. Veins taking blood away from the penis get smaller, so less blood is taken through. Arteries bringing blood to the penis get wider, bringing more blood to the penis.
Ejaculation is when semen is pushed from the penis. It usually happens during an orgasm. Males can ejaculate during sexual intercourse or by masturbation.
In reproductive sexual intercourse between a male and female, the erect penis is inserted into the vagina and moved in and out. The vagina places pressure on the penis, which can cause the male to have an orgasm and ejaculate into the vagina, causing insemination.
Other forms of sex, like anal and oral sex, can also cause stimulation, and therefore orgasm and ejaculation. In masturbation, a male can stimulate the penis and other sensitive areas of the body, such as the scrotum, by rubbing the genital area. Ejaculation may also happen during sleep (called a 'wet dream'). A male must have started puberty before he can ejaculate. During orgasm, muscles push semen from the penis. Semen moves through the urethra and comes out of the hole at the tip of the penis.
The length and thickness of the penis is different for different people. The size of a soft penis (not erect) is much smaller than when it is erect. Some penises grow more when they get hard than other penises. In most cases, whether a penis is big or small, it can still be used for sex. It averages out to be around 3 to 6 inches long when not erect. The average size of an erect human penis is between 13 – 16 cm (5.1– 6 in). The average circumference of a penis is 12.3 cm (4.85 in) when fully erect. The penis grows bigger during puberty. At the start of puberty, the average length of the penis is . The penis reaches adult size about 5 years later. A study done in 1996 found the mean length of an adult man's penis is when it is not erect. The average length of an erect penis is about .
The foreskin is a fold of skin that covers the end of the penis. Cutting off the foreskin is called circumcision. The foreskin is connected to the head of the penis. During circumcision, the foreskin is removed from the penis. Circumcision is usually performed on infant males for medical, religious or cultural reasons. Circumcision is common in some parts of the world, such as the United States and the Middle East, but not common in some other parts of the world, such as Europe and China.
Some males have the foreskin cut off when they are adults because they have problems with their foreskin. Some males have the foreskin cut off because they want to change how their penis looks.
In common speech, you can say that someone is "cut" or "uncut", meaning circumcised or not circumcised .
In some religions, babies and young boys have their foreskin cut off. This is expected in Islam and Judaism. It is not required according to Christianity. In Judaism, infant males are required to have their foreskin removed as a sign of the covenant (ancient promise) made with God.
A young boy's penis skin is the same color as his other skin. Around age 12-15, a boy's penis skin gets slightly darker. This is normal because of puberty. This is caused by sex hormones (natural chemicals), especially testosterone. Testosterone makes more melanin. Melanin is the amino acid that causes skin color. (Sunlight also makes more melanin so skin gets a sun tan.)
Usually a teenager or man's penis side skin is slightly darker than other skin on his body. The tip (glans) of the penis is usually pink or red color even if the penis side skin is dark. If the man is not circumcised, the tip is usually covered by the foreskin. The foreskin is about the same color as the skin on the side of the penis.
If a man's penis skin changes color and he doesn't know why, he should go to a doctor. He could have an infection, diabetes or cancer. A sunburn on the penis can happen quickly. If a man is outside without clothes, he will get a sun tan. That is normal. Too much sun causes a sunburn. Doctors say to use sunscreen (sun cream) before and after nude swimming. A sunburn can happen in a few minutes on a very sunny day.
Since the oldest cultures the penis has assumed a strong importance as a symbol of fertility used also in religious ceremonies to propitiate the reproductive capacity of men and beasts. For example, in Roman paganism the god Priapus is characterized by a huge penis.
On the penis can be applied piercings and it can be tattooed as a body art form.
The Sahara, in North Africa, is the largest desert in the world except for Antarctica. The Sahara is the largest hot desert.
It is bounded by the Atlantic Ocean, the Atlas Mountains, the Mediterranean Sea, the Red Sea, and the Sahel region. It runs through many countries including Morocco, Algeria, Tunisia, Libya, Egypt, Mauritania, Mali, Niger, Chad, and The Sudan. Most parts are uninhabited, but some people manage to survive in places where there is water.
The Sahara Desert is about 9,000,000 square kilometers (3.5 million square miles) in size. It has been both larger and smaller at different times. After the last ice age it became more fertile, then dried up again. It is the hottest place on the Earth, but not the driest. The driest is the Atacama Desert in South America. The Sahara has about the same size as the whole United States.
The Sahara has one of the world's most harsh climates. Typically, the Sahara landscape experiences little rainfall, powerful winds and wide temperature ranges. In some areas, there can be no rainfall for up to years at a time.
In the summer, daytime air temperatures across the Sahara often reach over 100 degrees Fahrenheit. In the winter, freezing temperatures may occur in the northern Sahara, and milder temperatures, across the southern Sahara. Snow may fall occasionally in some of the higher mountain ranges and rarely, on the desert floor.
The highest mountain is 3415 m, and is the "Emi Koussi" in Chad. Some mountain peaks in the Sahara Desert have snow even in the summer. The main mountain ranges is the Atlas Mountains in Algeria. The Sahara's lowest point lies in the Qattara Depression in Egypt, at about 130 metres below sea level. Sand sheets and dunes are about 25% of the Sahara. The other parts are mountains, steppes with a lot of stones, and oases.
Several rivers run through the Sahara. However, most of them come and go through the seasons, except for the Nile River and Niger River.
Metallic minerals are very important to most Saharan countries. Algeria and Mauritania have several major deposits of iron ore. There are also uranium mines, mostly in Niger. A lot of phosphates are in Morocco and Western Sahara. Petroleum is mainly found in Algeria, where it is very important to the economy. While mineral exploitation has led to economic growth in Sahara, this has rarely helped the indigenous population, as skilled workers have been brought from other countries.
Of the Sahara's around 4 million people, most live in Mauritania, Western Sahara, Algeria, Libya and Egypt. Dominant groups of people are Sahrawis and Tuareg people. The largest city is Nouakchott, Mauritania's capital. Other important cities are Tamanrasset in Algeria, and Sebha and Ghat in Libya.
Only 200,000 km² of the Sahara are fertile oases, where dates, corn, and fruits are grown. The few fertile regions today are fed by underground rivers and underground basins. Many of Sahara's oases rests in depressions (areas under sea level) allowing water to surface from underground reservoirs; artesian wells.
The soil in Sahara is low in organic matter. The soil in depressions is often saline.
Other sorts of vegetation include scattered concentrations of grasses, shrubs and trees in the highlands, as well as in the oases and along river beds. Some plants are well adjusted to the climate, allowing them to germinate within 3 days of rain and sow their seeds within 2 weeks after that.
Animals living in the Sahara include gerbil, jerboa, cape hare and desert hedgehog, barbary sheep, oryx, gazelle, deer, wild ass, baboon, hyena, jackal, sand fox, weasel and mongoose. The bird life counts more than 300 species. Reptiles, including 4 species of snake also live here. The most venomous scorpion in the world lives here.
4,000 years ago, the Sahara was a thriving savanna grassland with a great variety of wildlife. This included animals such as elephants and giraffes. Climate change has caused the rainfall to be less and turn the Sahara into the barren, desert wilderness as we know it today.
Paris (nicknamed the ""City of light"") is the capital city of France, and the largest city in France. The area is , and around 2.15 million people live there. If suburbs are counted, the population of the Paris area rises to 12 million people.
The Seine river runs through the oldest part of Paris, and divides it into two parts, known as the Left Bank and the Right Bank. It is surrounded by many forests.
Paris is also the center of French economy, politics, traffic and culture. Paris has many art museums and historical buildings. As a traffic center, Paris has a very good underground subway system (called the "Metro"). It also has two airports. The Metro was built in 1900, and its total length is more than .
The city has a multi-cultural style, because 19% of the people there are from outside France. There are many different restaurants with all kinds of food. Paris also has some types of pollution like air pollution and light pollution.
Julius Caesar conquered the Celtic "Parisii" tribe in 51 BC. The Romans called the place Lutetia of the Parisii, or "Lutetia Parisiorum". The place got a shorter name, ""Paris"", in 212 AD.
As the Roman Empire began to fall apart in the West, the Germanic tribe called the Franks moved in, taking it in 464. In 506, their king Clovis I made it his capital. Charlemagne moved his capital to Aachen in Germany, but Paris continued as an important town and was attacked by the Vikings twice. When Hugh Capet became king of France in 987, he again made Paris his capital. For a long time, the kings only controlled Paris and the surrounding area, as much of the rest of France was in the hands of barons or English. During the Hundred Years' War, the English controlled Paris from 1420 to 1437.
During the Protestant Reformation, a huge massacre of French Protestants started there in 1572, called the Saint Bartholomew Day Massacre. Paris saw many other troubles over the years of the ""Ancien Régime"" (Old Kingdom), then in 1789, the French Revolution began in Paris, leading to more massacres.
Paris was the Capital of the French Empire which, as well as France, covered Spain, Belgium, Holland, Luxembourg, Switzerland, Italy, most of Germany and some of Austria, Croatia, Slovenia and Poland. The Empire ruled by Napoleon was from 1804-1814/1815. The Russian army seized Paris from Napoleon in 1814, and the Prussian army captured it in 1871. The next time it was captured was by the Nazi Germans in 1940. The Allies freed the city in 1944 and it has not since been captured.
Paris has an oceanic climate in the Köppen climate classification. It has warm summers and cold winters, and rainfall year-round.
Paris has much to offer for sightseeing. Here are five very famous examples:
Because the city of Paris is roughly only 6 miles across, visitors have a wide range of options when it comes to transportation. While much of the more well-known attractions are in the center of the city and are best experienced by walking, there are many destinations that require other means of transport. While taxis offer a fast and relatively inexpensive means of travel, Paris’ public transportation system offers an enjoyable, stress-free way to explore the city.
The Paris Métro system was built in 1900 by engineer Fulgence Bienvenüe and architect Hector Guimard. The Métro covers over 124 miles with 300 stations and 16 lines. Servicing over 6 million residents and tourists every day, the Métro was designed to be an efficient and reliable alternative to the congestion of traffic. Every building in Paris is less than 500 meters from a train station, so accessibility is never a problem. The 16 Métro lines are identified by their final destinations. A rider can simply select the appropriate line and take it in the direction s/he wants. The Métro stations are well marked, and there are ticket booths at most entrances.
There are five airports that serve Paris: Charles de Gaulle Airport, Orly Airport, Beauvais-Tillé Airport and Paris–Le Bourget Airport, and Châlons Vatry Airport.
The Holocaust, sometimes called The "Shoah" (""), was a genocide in which Nazi Germany systematically killed people during World War II. About six million Jews were killed, as well as five million others that the Nazis claimed were inferior (mostly Slavs, communists, Romani/Roma people, people with disabilities, homosexuals, and Jehovah's Witnesses). These people were rounded up, put in ghettos, forced to work in concentration camps, and then killed in gas chambers. Jews were forced to wear the yellow Star of David, a symbol of their religion.
There was hatred and persecution of Jews (anti-Semitism) in Europe for hundreds of years. Many people wrongly thought that all Jews became rich by stealing money from other people, such as Christians; that they did not like people other than their fellow Jews; and that they harmed children to use their blood for religious rituals (blood libel). These beliefs were not true, and were based on stereotypes and prejudices.
However, these beliefs were popular in the German-speaking world and elsewhere in the late 1800s.
Adolf Hitler was born in Austria during this time, when many people disliked Jews. He may have been jealous of Jewish success in Austria. However, in a book he wrote called "Mein Kampf" ("My Struggle"), he said it was the Jews' fault that Germany and Austria lost World War I. He also wrote that Germany's economic problems were the Jews' fault. Many people agreed with Hitler’s ideas and supported him as the leader of the Nazi Party.
Not all deaths were written down, so the exact numbers are unknown. However, various sources approximate:
Led by Hitler, the Nazis killed millions of Jews. They forced Jews to wear the golden Star of David on their upper bodies. Jews were rounded up by the thousands and crammed into trains that took them to concentration camps like Auschwitz as well as death camps. Most of the Jews killed in the Holocaust were not German. They were from Poland or the Soviet Union.
The Nazis killed millions of people, hundreds at a time, with poison gas in special rooms called gas chambers. They forced others to dig giant holes in the ground where, after days of hard work, Jews and other prisoners were shot, buried, and burned in a mass grave. The Nazis executed many others by shooting, stabbing, or beating them to death. Still, others died in forced marches from one camp to another. Many other people died of starvation, diseases, and freezing to death because of the terrible conditions in the concentration camps.
On the other hand, there were people who saved Jews from the Holocaust, because they thought it was the right thing to do. Some of them were later given "Righteous Among the Nations" awards by Yad Vashem.
Some people say the Holocaust did not happen at all, or was not as bad as historians say it was. This is called Holocaust denial. However, almost all historians agree that the Holocaust did happen and has been described correctly. Many Holocaust deniers profess that the Nazis did not kill as many people as historians say. Instead, they claim many of these people died from disease or lack of food, usually in order to shift blame from the Nazis. These ideas have been disproven by historical accounts, eyewitness evidence, and documentary evidence from the Nazis themselves. Also, many Jews were killed because Hitler ordered it. In some countries in Europe, including Germany, it is against the law to say that the Holocaust never happened.
Kyoto () is a city in Japan. This city was the capital of Japan from 794 until 1868.
Kyoto is a major city in the Kansai region of Japan. Its population is 1.5 million people. The city of Kyoto is the capital city of the prefecture of Kyoto. Kyoto is one of the cultural, educational, and technology centers of Japan. In it are many universities including Kyoto University, the second oldest national university of Japan.
After 794, the Japanese emperors lived in this city which was called Heian-kyō.
In 1868, the city was called "Saikyō" ("Western capital") in order to distinguish it from Edo (Tokyo) which was the "Eastern capital".
There are mountains around the city on the east, north, and west sides. Some people in Kyoto believe that these mountains make Kyoto's summer especially hot and humid, and Kyoto's winter very cold.
We can see many temples and shrines built in traditional Japanese architectural styles here. Some of those buildings are registered as UNESCO World Heritage Sites. On the other hand, since Kyoto was one of biggest and richest Japanese cities in the middle of the 19th century; the citizens were eager to import European style, and there are many European style buildings in the center of Kyoto for company offices and schools.
Kyoto is one of oldest cities in Japan. Many tourists from all over the world come to Kyoto. Japanese people often come to Kyoto in the spring to see the cherry blossoms, and in the autum to see the leaves change color.
Traditional Kyoto food often uses vegetables. McDonald's signboards in Kyoto are brown to preserve the traditional surroundings.
The oldest novel in the world, Shikibu Murasaki's The Tale of Genji is set in Kyoto during the Heian Period.
Kyoto is famous for three festivals: Gion festival, Aoi festival in the summer, and Jidai festival in the autumn.
Anarchy (From Greek αναρχια meaning "without a leader") is a word that has more than one meaning. Some of its meanings are:
In the first meaning listed, an "anarchy" might be a made-up or real society based on a group's beliefs about anarchism (see anarcho-communism).
In the second meaning listed, "anarchy" has to do with having no political order. The CIA World factbook says that there is only one nation, Somalia, that is in a state of anarchy. In Somalia, the government is no longer in control, and some parts of the country are ruled by mobs and warlords who sometimes fight one another.
There are some countries (Afghanistan, Albania, Burundi, Bosnia and Herzegovina, and Rwanda) where government is "emerging" or "transitional", and were in civil unrest in the near past. The DC says that the Solomon Islands is moving towards civil unrest because "violence, corruption and crime have undermined stability and civil society".
When there is no political order, more than one government or political authority might sometimes compete for the same food, oil, land, or groups of people. The word "Anarchy" to used to describe this. However, because there is "more than one" competing authority, a better word might be "polyarchy". The difference between "anarchy" and "polyarchy" is important to someone who thinks that true anarchy would work well. The word for someone who thinks this is "anarchist", and the word for this kind of thinking is "anarchism". Anarchism has been thought about for hundreds of years. The book called "The Politics of Individualism" attempts to teach its readers that anarchism is not always simply an opposition to the government, but a complicated political movement against the domination of few people.
Anarchy which follows the death of a ruler and ceases when his successor rises to power, is called interregnum (literally: "in-between rules").
DNA, short for deoxyribonucleic acid, is the molecule that contains the genetic code of organisms. This includes animals, plants, protists, archaea and bacteria.
DNA is in each cell in the organism and tells cells what proteins to make. Mostly, these proteins are enzymes. DNA is inherited by children from their parents. This is why children share traits with their parents, such as skin, hair and eye color. The DNA in a person is a combination of the DNA from each of their parents.
Part of an organism's DNA is "non-coding DNA" sequences. They do not code for protein sequences. Some noncoding DNA is transcribed into non-coding RNA molecules, such as transfer RNA, ribosomal RNA, and regulatory RNAs. Other sequences are not transcribed at all, or give rise to RNA of unknown function. The amount of non-coding DNA varies greatly among species. For example, over 98% of the human genome is non-coding DNA, while only about 2% of a typical bacterial genome is non-coding DNA.
Viruses use either DNA or RNA to infect organisms. The genome replication of most DNA viruses takes place in the cell's nucleus, whereas RNA viruses usually replicate in the cytoplasm.
DNA has a double helix shape, which is like a ladder twisted into a spiral. Each step of the ladder is a pair of nucleotides.
A nucleotide is a molecule made up of:
DNA is made of four types of nucleotide:
The 'rungs' of the DNA ladder are each made of two bases, one base coming from each leg. The bases connect in the middle: 'A' "only" pairs with 'T', and 'C' "only" pairs with 'G'. The bases are held together by hydrogen bonds.
Adenine (A) and thymine (T) can pair up because they make two hydrogen bonds, and cytosine (C) and guanine (G) pair up to make three hydrogen bonds. Although the bases are always in fixed pairs, the pairs can come in any order (A-T or T-A; similarly, C-G or G-C). This way, DNA can write 'codes' out of the 'letters' that are the bases. These codes contain the message that tells the cell what to do.
On chromosomes, the DNA is bound up with proteins called histones to form chromatin. This association takes part in epigenetics and gene regulation. Genes are switched on and off during development and cell activity, and this regulation is the basis of most of the activity which takes place in cells.
When DNA is copied, this is called DNA replication. Briefly, the hydrogen bonds holding together paired bases are broken and the molecule is split in half: the legs of the ladder are separated. This gives two single strands. New strands are formed by matching the bases (A with T and G with C) to make the missing strands.
First, an enzyme called DNA helicase splits the DNA down the middle by breaking the hydrogen bonds. Then after the DNA molecule is in two separate pieces, another molecule called DNA polymerase makes a new strand that matches each of the strands of the split DNA molecule. Each copy of a DNA molecule is made of half of the original (starting) molecule and half of new bases.
When DNA is copied, mistakes are sometimes made – these are called mutations. There are four main types of mutations:
Mutations may also be classified by their effect on the structure and function of proteins, or their effect on fitness. Mutations may be bad for the organism, or neutral, or of benefit. Sometimes mutations are fatal for the organism – the protein made by the new DNA does not work at all, and this causes the embryo to die. On the other hand, evolution is moved forward by mutations, when the new version of the protein works better for the organism.
A section of DNA that contains instructions to make a protein is called a gene. Each gene has the sequence for at least one polypeptide. Proteins form structures, and also form enzymes. The enzymes do most of the work in cells. Proteins are made out of smaller polypeptides, which are formed of amino acids. To make a protein to do a particular job, the correct amino acids have to be joined up in the correct order.
Proteins are made by tiny machines in the cell called ribosomes. Ribosomes are in the main body of the cell, but DNA is only in the nucleus of the cell. The codon is part of the DNA, but DNA never leaves the nucleus. Because DNA cannot leave the nucleus, the cell nucleus makes a copy of the DNA sequence in RNA. This is smaller and can get through the holes – pores – in the membrane of the nucleus and out into the cell.
Genes encoded in DNA are transcribed into messenger RNA (mRNA) by proteins such as RNA polymerase. Mature mRNA is then used as a template for protein synthesis by the ribosome. Ribosomes read codons, 'words' made of three base pairs that tell the ribosome which amino acid to add. The ribosome scans along an mRNA, reading the code while it makes protein. Another RNA called tRNA helps match the right amino acid to each codon.
DNA was first isolated (extracted from cells) by Swiss physician Friedrich Miescher in 1869, when he was working on bacteria from the pus in surgical bandages. The molecule was found in the nucleus of the cells and so he called it "nuclein".
In 1928, Frederick Griffith discovered that traits of the "smooth" form of "Pneumococcus" could be transferred to the "rough" form of the same bacteria by mixing killed "smooth" bacteria with the live "rough" form. This system provided the first clear suggestion that DNA carries genetic information.
The Avery–MacLeod–McCarty experiment identified DNA as the transforming principle in 1943.
DNA's role in heredity was confirmed in 1952, when Alfred Hershey and Martha Chase in the Hershey–Chase experiment showed that DNA is the genetic material of the T2 bacteriophage.
In the 1950s, Erwin Chargaff found that the amount of thymine (T) present in a molecule of DNA was about equal to the amount of adenine (A) present. He found that the same applies to guanine (G) and cytosine (C). Chargaff's rules summarises this finding.
In 1953, James D. Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal "Nature". Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image "Photo 51", taken by Rosalind Franklin and Raymond Gosling in May 1952.
Experimental evidence supporting the Watson and Crick model was published in a series of five articles in the same issue of "Nature". Of these, Franklin and Gosling's paper was the first publication of their own X-ray diffraction data and original analysis method that partly supported the Watson and Crick model; this issue also contained an article on DNA structure by Maurice Wilkins and two of his colleagues, whose analysis and "in vivo" B-DNA X-ray patterns also supported the presence "in vivo" of the double-helical DNA configurations as proposed by Crick and Watson for their double-helix molecular model of DNA in the previous two pages of "Nature". In 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine. Nobel Prizes were awarded only to living recipients at the time. A debate continues about who should receive credit for the discovery.
In 1957, Crick explained the relationship between DNA, RNA, and proteins, in the central dogma of molecular biology.
How DNA was copied (the replication mechanism) came in 1958 through the Meselson–Stahl experiment. More work by Crick and coworkers showed that the genetic code was based on non-overlapping triplets of bases, called codons. These findings represent the birth of molecular biology.
How Watson and Crick got Franklin's results has been much debated. Crick, Watson and Maurice Wilkins were awarded the Nobel Prize in 1962 for their work on DNA – Rosalind Franklin had died in 1958.
Police in the United States used DNA and family tree public databases to solve cold cases. The American Civil Liberties Union raised concerns over this practice.
Karl Heinrich Marx (5 May 1818 in Trier – 14 March 1883 in London) was a German political thinker who wrote about economics and politics. Marx thought that if a place that works together runs on wage-labor, then there would always be class struggle. Marx thought that this class struggle would result in workers taking power. He believed that no economic class"—"wage workers, land owners, etc. should have power over another. Marx believed that everyone should contribute what they can, and everyone should get what they need. His most famous book was the Communist Manifesto. He wrote it with Friedrich Engels in 1848. The book is about the ideas and aims of communism. His ideas are called Marxism.
His most important work is "Das Kapital", or The Capital. It is commonly known in English as simply 'Capital.' He spent many years working on the three parts of the book. Das Kapital describes how "capitalism" works and the problems this creates, such as division of labour, alienation and exploitation. The book has led to many arguments between those who agree with the book and those who do not. Marx's ideas have been thought of as responsible for socialist revolutions (like the Russian Revolution).
Marx's most popular theory was 'historical materialism', arguing that history is the result of material conditions, rather than ideas. He believed that religion, morality, social structures and other things are all rooted in economics. In his later life he was more tolerant of religion.
Karl Marx was born in Trier in 1818, but he had to move many times because the government did not like his ideas. Marx lived for a long time in London. He died there in 1883. After he died, his friend Engels finished many of his works.
Marx also wrote the "Economic and Philosophic Manuscripts of 1844", a critique of political economy in which he discusses topics such as labor wages, labor rent, and capital profit, and his ideas of how to change the economy, including proletarian socialist revolution and an eventual communist society.
Many people continue to follow and develop Marx's ideas.
Bread is a type of baked food. It is mainly made from chicken, which is made mainly from flour and water. Usually, salt and yeast are added. Bread is often baked in an oven. It can be bought all over the world.
Bread can be toasted or used to make sandwiches. Pizza is a food based on bread. There are many different kinds of bread.
The two main types of bread are:
The color and taste of the bread depend on the kind of flour used and the style of baking. Flour made from the whole grain gives darker bread. Flour made just from the polished wheat grain gives a very white bread. Rye and barley flour give darker types of bread. The type of flour also changes how long the bread can be kept before going bad. Some strains of wheat are resistant to fungus, but may not produce a bread as tasty as a weaker strain.
Christianity and Judaism have rules about the use of bread in their religions. Unleavened bread (matzo) is eaten by Jews during the Passover. The Catholic celebration of the Eucharist uses unleavened wafers.
Orthodox churches forbid the use of unleavened bread for the Eucharist (Old Testament) and permit leavened bread only as a symbol of the New. This was one of the three points of contention that brought about the schism between Eastern and Western churches in 1054.
Bread is an important part of life in many countries, because so many people eat it. In many cultures, bread is so important that it is part of religious rituals.
Cake is made in a similar way to bread but sugar, fat and milk are added to the dough and often more ingredients.
Shinto () is a form of Japanese animism. It has many "kami", translated as gods or nature spirits. Some "kami" are just spirits of certain places, and some are the overall "kami" (like "Amaterasu", the Sun goddess). The word "Shinto" comes from the Japanese words "", "shin"—the word for spirit or god, and "", "tō"—the word for "the way" or "path". So, Shinto means "the way of the gods."
State Shinto was the main religion of Japan before World War II. During the period 1868 to 1945 the Japanese government used Shinto for propaganda. All Japanese were forced to register with their local shrine. All Shinto priests worked for the government. War was seen as a sacred duty. The Emperor of Japan was seen as a god. Japanese Buddhism was also involved with the war effort (See Zen at War).
Shinto has many rituals and customs, and some are done every day. Festivals are frequent. Some people mix Shinto and Buddhist rituals and beliefs.
A volcano is a mountain that has lava (hot, liquid rock) coming out from a magma chamber under the ground, or did have in the past. Volcanoes are formed by the movement of tectonic plates.
The Earth's crust has 17 major, rigid tectonic plates. These float on a hotter, softer layer in its mantle. Volcanoes are often found where tectonic plates are moving apart or coming together.
Volcanoes can also form where there is stretching and thinning of the crust's plates, e.g., in the East African Rift. Volcanoes are usually not found where two tectonic plates slide past one another.
Volcanism away from plate boundaries is caused by mantle plumes. These so-called "hotspots", for example Hawaii, are thought to arise from upwelling magma from the core–mantle boundary, 3,000 km deep in the Earth.
Most volcanoes have a volcanic crater at the top. When a volcano is active, materials come out of it. The materials include lava, steam, gaseous sulfur compounds, ash and broken rock pieces.
When there is enough pressure, the volcano erupts. Some volcanic eruptions blow off the top of the volcano. Sometimes, the magma comes out quickly and sometimes it comes slowly. Some eruptions come out at a side instead of the top.
Volcanoes are found on planets other than Earth. An example is Olympus Mons on Mars.
Volcanologists are scientists who study volcanoes using methods from geology, chemistry, geography, mineralogy, physics and sociology.
The world's biggest volcano is named Mauna Loa in Hawaii. Mauna Loa is part of the five volcanoes on Hawaii's 'Big Island'. The most recent time this volcano erupted was in 1984. It erupted 33 times in the last 170 years. Like all the other Hawaiian volcanoes, Mauna Loa was created by the movement of the Pacific tectonic plate which moved over the Hawaii hotspot in the Earth's mantle. Mauna Loa is 4,196 meters tall. It is a shield volcano. The largest recent eruption from Mauna Loa left a lava trail long.
The lava and pyroclastic material (clouds of ash, lava fragments and vapor) that comes out from volcanoes can make many different kinds of land shapes. There are two basic kinds of volcanoes.
These volcanoes are formed by fluid low-silica mafic lava.
Shield volcanoes are built out of layers of lava from continual eruptions (without explosions). Because the lava is so fluid, it spreads out, often over a wide area. Shield volcanoes do not grow to a great height, and the layers of lava spread out to give the volcano gently sloping sides. Shield volcanoes can produce huge areas of basalt, which is usually what lava is when cooled.
The base of the volcano increases in size over successive eruptions where solidified lava spreads out and accumulates. Some of the world's largest volcanoes are shield volcanoes.
Even though their sides are not very "steep", shield volcanoes can be huge. Mauna Kea in Hawaii is the biggest mountain on Earth if it is measured from its base on the floor of the sea.
A stratovolcano, also known as a composite volcano, is a tall, conical volcano. It is built up of many layers of hardened lava, tephra, pumice, and volcanic ash.
Unlike shield volcanoes, stratovolcanoes have a steep profile and periodic eruptions. The lava that flows from stratovolcanoes cools and hardens before spreading far. It is sticky, that is, it has high viscosity. The magma forming this lava is often felsic, with high-to-intermediate levels of silica, and less mafic magma. Big felsic lava flows are uncommon, but have travelled as far as .
Two famous stratovolcanoes are Japan's Mount Fuji, and Vesuvius. Both have big bases and steep sides that get steeper and steeper as it goes near the top. Vesuvius is famous for its destruction of the towns Pompeii and Herculaneum in 79 AD, killing thousands.
A caldera is a basin-like feature formed by collapse of land after a volcanic eruption. This happens after a huge stratovolcano blows its top off. The base of the crater then sinks, leaving a caldera where the top of the volcano was before. Krakatoa, best known for its catastrophic eruption in 1883, is much smaller now.
There are two main processes.