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Influenza
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Influenza, better known as the flu and sometimes called the grippe, is a common childhood illness, but is not as common among adults. It is not limited to humans, most mammals and many birds can also catch influenza. It is caused by several different viruses, termed influenza viruses A, B, C, and D.
Flu transmission and symptoms.
Human influenza can pass from one person to another very easily. It is most commonly spread by the microscopic droplets of mucus and fluid that are sent into the air when the sick person coughs or sneezes. Symptoms include cough, sore throat, muscle aches and pains, fever, headache, and rarely vomiting and diarrhea. Influenza can also lead to other diseases, such as pneumonia. This makes it especially dangerous to young children and elderly people.
Although there is no cure for influenza, antiviral drugs can be used to treat the illness so it is not as severe and does not last as long. Influenza vaccines are available worldwide, and are quite effective. They are changed each year as the virus changes.
The influenza season runs from late fall to spring because most people catch it in the winter months. When there are more cases of influenza than expected, it will sometimes be called an epidemic. When there are a large number of cases of the same type of influenza all over the world, it is often called a pandemic.
History.
The virus is ancient. It has infected humans for centuries.
Changes in the influenza virus.
Small changes that happen as flu is passed from one person to another is the most common way flu viruses change. This is the main reason that people can catch the flu every year.
The CDC keeps track of the different flu viruses that are circulating, and gives this information to the companies that make flu "shots". Since the flu changes so much from year to year, flu shots have to be given each new flu season.
Flu shots only protect against the most common flu viruses, and every now and then a slightly different type spreads more than expected. Usually when this happens, the existing flu shot gives some protection so that even if a person who had a flu shot catches it, they do not get as sick.
Some flu viruses are caught from animals. Bird flu, for example, is usually only caught by people in contact with sick birds (usually chickens). These types of flu virus are usually very limited, and while they can make a person very ill, usually other people do not catch the virus from the sick person.
Another way that the flu can change is when a person or animal catches two different flu viruses. The two viruses can exchange some of their genetic information, which can create a brand new flu that nobody has ever caught before.
If an animal flu virus changes in this way to one that can easily pass from human to human, many people become ill because nobody has any immunity to the new virus. Often, a brand new virus is more severe and kills more people.
New types of flu virus are usually what causes pandemics, and that is the reason many scientists have been following bird flu so closely—it kills six people out of every ten who catch it. This would be a very serious problem if it changes enough to spread easily between people.
Swine flu (March/April 2009).
This new flu virus got its name because it contains genetic parts that are commonly found in flu viruses that infect pigs. It is not spread by pigs or by eating pork—this is a new human virus being spread by humans. The name was the 2009 flu pandemic.
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Pancreas
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The pancreas is an organ that makes hormones and enzymes to help digestion. The pancreas helps break down carbohydrates, fats, and proteins. The pancreas is behind the stomach and is on the left side of the human body.
The part of the pancreas that makes hormones is called the Islets of Langerhans. The Islets of Langerhans are a small part (2%) of the total cells in the pancreas. The Islets of Langerhans change which chemical they make depending on how much of other chemicals are already in the blood. So, the pancreas works to keep the level of chemicals in balance in the body. If the Islets of Langerhans stop working, a person will suffer from a disease called diabetes.
The pancreas belongs to two systems of the body: the digestive system for its role in breaking down nutrients, and the endocrine system for producing hormones.
Research: Doctors are experimenting with taking the Islets of Langerhans cells from a donor body and putting them into the pancreas of a person with diabetes to make that person well.
Hormones.
The pancreas releases these hormones:
Digestive enzymes.
The pancreas releases many different enzymes to help digestion:
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Chloroplast
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A chloroplast is a small organelle inside the cells of plants and algae. They absorb light to make sugar in a process called photosynthesis. The sugar can be stored in the form of starch.
Chloroplasts contain the molecule chlorophyll, which absorbs sunlight for photosynthesis. In addition to chlorophyll, a chloroplast uses carbon dioxide (CO2) and water (H2O) to form sugar and gives off oxygen (O2).
Chlorophyll is what gives green plants their green colour. Chloroplasts also contain various yellow and orange pigments to assist in photon capture for photosynthesis.
Structure.
Each chloroplast is surrounded by a double walled semi-permeable membrane. These are collectively known as peristromia. In the layered stacks are flat disk-shaped thylakoids. They contain light-absorbing pigments, including chlorophyll and carotenoids, as well as proteins which bind the pigments. Like mitochondria, chloroplasts also contain their own DNA and ribosomes.
Evolution.
Chloroplasts are one of the many different types of organelles in the cell. They may have originated as endosymbiotic cyanobacteria. This was suggested by Konstantin Mereschkowski in 1905, after an observation by Schimper in 1883 that chloroplasts closely resembled cyanobacteria.
Almost all chloroplasts are thought to derive directly or indirectly from a single endosymbiotic event.
Mitochondria also had a similar origin, but chloroplasts are found only in plants and protists. In green plants, chloroplasts are surrounded by two lipid-bilayer membranes. They may be the outer and inner membranes of the ancestral cyanobacterium. Chloroplasts have their own genome, much smaller than that of free-living cyanobacteria. The DNA which remains shows clear similarities with the cyanobacterial genome.
Plastids may contain 60–100 genes whereas cyanobacteria often contain more than 1500 genes. Many of the missing genes are encoded in the nuclear genome of the host.
In some algae (such as the heterokonts), chloroplasts seem to have evolved through a secondary event of endosymbiosis, in which a eukaryotic cell engulfed a second eukaryotic cell containing chloroplasts. This formed chloroplasts with three or four membrane layers. In some cases, such secondary endosymbionts may have themselves been engulfed by still other eukaryotes, so forming tertiary endosymbionts. In the alga "Chlorella", there is only one chloroplast, which is bell-shaped.
In some groups of mixotrophic protists such as the dinoflagellates and some sea slugs, chloroplasts are separated from a captured alga or diatom and used temporarily. These klepto (stolen) chloroplasts may only have a lifetime of a few days and are then replaced.
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Chlorophyll
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Chlorophyll is a pigment that gives plants their green colour. Chlorophyll is a chemical in the chloroplasts of plants. It allows plants to absorb and use light. Energy from the light is used in photosynthesis to make glucose. This contains lots of stored energy which the plant needs to release. It does this through respiration. This energy is then used when the plant grows or repairs damage. Chlorophyll also makes the stem and leaf of the plant green.
Chlorophyll is a green pigment in almost all plants, algae, and cyanobacteria. It absorbs light most strongly in the blue portion of the electromagnetic spectrum, followed by the red portion. However, it is a poor absorber of green and near-green portions of the spectrum. Chlorophyll was first isolated in 1817.
Chlorophyll and photosynthesis.
Chlorophyll is necessary for photosynthesis, which allows plants to obtain energy from light.
Chlorophyll molecules are arranged in and around the membranes of chloroplasts. It serves two main functions. The function of most chlorophyll (up to several hundred molecules per photosystem) is to absorb light and transfer that light energy to reaction centres. These pigments are named after the wavelength (in nanometers) of their red-peak absorption maximum. These chlorophyll pigments can be separated in a simple paper chromatography experiment.
The function of the reaction center chlorophyll is to use the energy transferred to it from the other chlorophyll pigments to undergo a specific redox reaction. In this reaction the chlorophyll gives an electron to an electron transport chain. This reaction is how photosynthetic organisms such as plants produce O2 gas, and is the source for practically all the O2 in Earth's atmosphere. Photosystem I typically works in series with Photosystem II.
The electron flow produced by the reaction center chlorophyll pigments is used to shuttle H+ ions across the membrane, setting up a chemiosmotic potential used mainly to produce ATP chemical energy; and those electrons ultimately reduce NADP+ to NADPH, a universal reductant used to reduce CO2 into sugars as well as for other biosynthetic reductions.
A green sea slug, "Elysia chlorotica", has been found to use the chlorophyll it has eaten to perform photosynthesis for itself. This process is known as kleptoplasty, and no other animal has been found to have this ability.
Why green and not black?
It still is unclear exactly why plants have mostly evolved to be green. Green plants reflect mostly green and near-green light rather than absorbing it. Other parts of the system of photosynthesis still allow green plants to use the green light spectrum (e.g. through a light-trapping leaf structure, carotenoids, etc.). Green plants do not use a large part of the visible spectrum as efficiently as possible. A black plant can absorb more radiation, and this could be very useful, notwitstandanding the problems of disposing of this extra heat (e.g. some plants must close their openings, called stoma, on hot days to avoid losing too much water). More precisely, the question becomes why the only light absorbing molecule used for power in plants is green and not simply black.
The biologist John Berman has said that evolution is not an engineering process, so it often has limits that an engineer or other designer does not. Even if black leaves were better, evolution's limitations can prevent species from becoming as efficient as possible. Berman wrote that achieving pigments that work better than chlorophyll could be very difficult. In fact, all higher plants (embryophytes) are believed to have evolved from a common ancestor that is a sort of green algae – so chlorophyll has evolved only once (common ancestor).
Shil DasSarma, a microbial geneticist at the University of Maryland, has pointed out that species of archaea use another light-absorbing molecule, retinal, to get power from the green spectrum. Some scientists believe that green-light-absorbing archae were once the most common in the earth environment. This could have left open a "niche" for green organisms which would absorb the other wavelengths of sunlight. This is just a possibility, and Berman wrote that scientists are still not convinced of any one explanation.
Chemical structure.
Chlorophyll is a chlorin pigment, which is structurally similar to and produced through the same metabolic pathway as other porphyrin pigments such as haem. At the center of the chlorin ring is a magnesium ion. For the structures depicted in this article, some of the ligands attached to the Mg2+ center are omitted for clarity. The chlorin ring can have several different side chains, usually including a long phytol chain. There are a few different forms that occur naturally, but the most widely distributed form in terrestrial plants is chlorophyll "a". The general structure of chlorophyll "a" was worked out by Hans Fischer in 1940. By 1960, when most of the stereochemistry of chlorophyll "a" was known, Robert Burns Woodward published a total synthesis of the molecule. In 1967, the last remaining stereochemical elucidation was completed by Ian Fleming, and in 1990 Woodward and co-authors published an updated synthesis. In 2010, a near-infrared-light photosynthetic pigment called chlorophyll f might have been discovered in cyanobacteria and other oxygenic microorganisms that form stromatolites.
The different structures of chlorophyll are summarized below:
Measuring chlorophyll.
Chlorophyll Content meters measure the optical absorption of a leaf to estimate its chlorophyll content. Chlorophyll molecules absorb in the blue and red bands, but not the green and infra-red bands. Chlorophyll content meters measure the amount of absorption at the red band to estimate the amount of chlorophyll present in the leaf. To compensate for varying leaf thickness, Chlorophyll Meters also measure absorption at the infrared band which is not significantly affected by chlorophyll.
The chlorophyll content of leaves can be non-destructively measured using hand-held, battery-powered meters. The measurements made by these devices are simple, quick and relatively inexpensive. They now have large data storage capacity, averaging and graphical displays.
Spectrophotometry.
Measurement of the absorption of light is complicated by the solvent used to extract it from plant material, which affects the values obtained,
Biosynthesis.
In Angiosperms, the last step in the synthesis of chlorophyll is light-dependent. Such plants are pale (etiolated) if grown in the darkness. Non-vascular plants and green algae have an additional light-independent enzyme and grow green in the darkness instead.
Chlorosis is a condition in which leaves do not make enough chlorophyll, so they become yellow. Chlorosis can be caused by a not having enough iron—called iron chlorosis—or by not having enough magnesium or nitrogen. Soil pH sometimes affects these kinds of chlorosis. Many plants are adapted to grow in soils with specific pH levels and their ability to absorb nutrients from the soil can depend on this. Chlorosis can also be caused by pathogens including viruses, bacteria and fungal infections, or sap-sucking insects.
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Oak
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The oak tree is a tree or shrub in the genus Quercus. There are about 500 living species. They are divided into subgenera. The common name "oak" may also appear in the names of species in related genera, such as "Lithocarpus".
Oaks have spirally arranged leaves, with rounded edges in many species; some have leaves with jagged edges or entire leaves with smooth margins. Many deciduous species do not drop dead leaves until the next Spring. In Spring, a single oak tree produces both male flowers (as catkins) and small female flowers. The fruit is a nut called an acorn, carried in a cup-like structure. Each acorn has one seed (rarely two or three) and takes 6–18 months to mature, depending on species. The so-called "live oaks" are evergreen. They are not a taxonomic group, just a life style which occurs in the genus.
The oak is a kind of hardwood forest tree. They are well known as a climax vegetation in the temperate zone of the northern hemisphere. That means, left untouched by humans, it would be the dominant tree. Much of England was covered by oak forests before modern farming took over the land. The last extensive oak woodlands were cut down to build ships for the Royal Navy in the 18th century.
Some kinds of oak wood are very hard. That is why people in past centuries cut them down to make ships, furniture and other things. The wood is now scarce and expensive and only used to make a few things anymore. Much cheaper are softwoods like pine.
Oak trees grow slowly and can live up to 1000 years.
Associated animals.
A mature oak tree stands about 100 feet tall (~30 metres). It is a home for more animals than any other European tree. 30 species of birds, 45 different bugs and over 200 species of moth have been found on oaks. Beetles burrow under the bark, and some drill holes into the wood. The leaves are eaten by many caterpillars. Many leaves carry strange little bumps on the underside. These are insect galls, caused by many little animals. Midges, moths, worms and tiny wasps lay their eggs in leaves or leaf buds. The leaf reacts by forming a growth around the eggs. Inside the gall, larvae develop. The leaf falls, but the larvae may come out only the next spring. Small galls only have one larva, but larger galls may contain as many as 30 larvae.
Acorns.
Oak trees produce acorns once a year which ripen in autumn. Oak trees may start producing acorns when they are about 20 years old. A mature oak may produce 90,000 acorns a year; this is several millions in its lifetime.
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Glucose
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Glucose () is a simple carbohydrate, or "sugar". It is one of several kinds of sugars. It is important because cells in an organism use it as a source of energy. Turning glucose into energy is called cellular respiration, which is done inside the cells of a living organism. Excess glucose is converted to fats and are stored in adipose tissues.
Glucose is made by plants in a process called photosynthesis. It can also be made by animals in their liver or kidneys.
Having the right amount of glucose available in a person's body is important. Glucose is essential in the proper functioning of the brain. It can be measured with a simple blood test. People that do not have enough glucose have low blood sugar levels. This is a health condition called hypoglycemia. People with too much glucose have hyperglycemia. They might have a health condition called diabetes.
Its chemical formula is C6H12O6. This means it has six carbon atoms, 12 hydrogen atoms, and six oxygen atoms bonded together.
How sugars work, and how glucose can be formed, was studied by a German chemist named Emil Fischer in the 1890s. His work earned him the 1902 Nobel Prize in Chemistry.
Isomers.
There are two forms of glucose, the α- and β- forms. The only difference between them is the position of the hydroxyl group, above and below the plane of the ring of the molecule.
For α-glucose, the hydroxyl (-OH) group is below the ring, while for β-glucose, the (-OH) group is above.
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Cellulose
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Cellulose is the main chemical that forms the main structure of plants. It is the most abundant macromolecule and the most common organic compound on Earth. It is also a kind of fiber. Cellulose is a very complex carbohydrate, consisting of 3,000 or more glucose units. Cellulose was discovered by Anselme Payen in 1838. He isolated it from plant matter and determined its chemical formula.
Properties.
Cellulose has no taste. It is odorless and hydrophilic, meaning it attracts water. It is insoluble in water and most organic solvents. It is chiral and is biodegradable.
Cellulose is made from a form of glucose and makes up most of the cell wall of plant cells. This is what keeps a plant in shape. Humans and other animals cannot digest cellulose but some animals such as termites and ruminants use bacteria to digest it.
It is a polysaccharide, which is repeating units of a monosaccharide joined together by a glycosidic bond by a condensation reaction. It is very tough because when you join beta glucose together, they are opposite ways up. The bonds are straight, forming straight chains. There are hydrogen bonds between the polymers.
These fibers are in bundles of about 40, called microfibrils. Microfibrils are embedded in a hydrated network of other polysaccharides. The cell wall is assembled in place. The parts are made inside the cell and then assembled by enzymes associated with the cell membrane.
Uses.
It is mainly used to make paper. It is also used to make as cotton, linen, and rayon for clothes, nitrocellulose for explosives, and cellulose acetate for films. Cellulose is used as insulation in transformers, cables, and other electrical equipment. Microcrystalline cellulose and powdered cellulose are used as inactive fillers in drug tablets. Cellulose derivatives are used as emulsifiers, thickeners and stabilizers in processed foods. Cellulose can be converted into cellophane. Cellulose is used to make water-soluble adhesives and binders such as methyl cellulose and carboxymethyl cellulose.
Celluose can also be used as an anti-caking agent in some foods like pre-shredded cheese.
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Leaves
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Wikiquote
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Wikiquote is a sister project of Wikipedia. It is one of many projects run by the Wikimedia Foundation.
Wikiquote was based on an idea by Daniel Alston and made by Brion Vibber. The goal of the project is to produce a large reference of quotations from famous people, books, and proverbs, and to give details about them.
Languages.
The project was first created in English. Meanwhile, in July 2004, more languages were added. Some of there are:
As of May 2016, 31 versions each have more than 1,000 articles. The largest Wikiquote is the English project with over 26,500 content pages, followed by the Italian and Polish versions, both with over 22,000 content pages. In total, 60 languages have over 100 content pages.
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Brasília
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Brasília () is the capital city of Brazil. The name is commonly spelled "Brasilia" in English. The city and its Federal District are in the Central-West region of the country. It is on a plateau known as "Planalto Central". Brasília has a population of about 2,557,000 (3,599,000 in the metropolitan area) as of the 2008 IBGE estimate. It is the fourth largest city in Brazil. But the Brasília metropolitan area is the sixth largest in the nation. It is listed as a World Heritage Site. Brasília hosts 124 foreign embassies.
Viewed from above, the main portion of the city resembles an airplane or a butterfly. The Monumental Axis goes east-west and holds government buildings and monuments. The other axis is curved in a north south direction. The city is commonly referred to as "Capital Federal", or simply "BSB". As the national capital, Brasília is the seat of all three branches of the Brazilian government. The city also hosts the headquarters of many Brazilian companies. Planning policies place residential buildings around expansive urban areas. The plan includes large avenues. It divides the city into sectors with different purposes, including accommodation and tourism. The city is built around an artificial lake, Lake Paranoá.
Residents of Brasília are known as "brasilienses" or "candangos". (The "candangos" are people who moved to Brasília when the city was established). In local usage, the word "Brasília" usually refers only to the First Administrative Region within the Distrito Federal (Federal District), where the most important government buildings are. Brasília has a unique status in Brazil, as it is an administrative division rather than a legal municipality like nearly all cities in Brazil. In the rest of Brazil, Brasília is almost always means the Brazilian Federal District. There are several "satellite cities," which are also part of the Federal District.
History.
The city was planned and developed as a new town in 1956. Lúcio Costa was the principal urban planner and Oscar Niemeyer was the principal architect. Roberto Burle Marx was the landscape designer. They created the "Plano Piloto de Brasília". Brasília was built in 41 months, from 1956 to April 21, 1960.
On 8 January 2023, supporters of former President Jair Bolsonaro stormed and invaded the Praça dos Três Poderes in Brasília, taking over the offices of the Supreme Federal Court, National Congress of Brazil and the Palácio do Planalto. The event was seen as an attempted coup d'état to overturn the election results of the 2022 general election.
Transportation.
The Brasília subway system ("Metrô de Brasília") has 24 stations on two lines long. The subway currently covers the south half of the metropolitan area. In 2010, a light rail line was added. By 2014, the light rail line will go from the end of the north wing of the city to the airport in the south.
Brasília International Airport is the main airport in Brasília, connecting the capital to all major Brazilian cities and many airports in other countries. It is the third most important airport of Brazil, in terms of passengers and aircraft movements.
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Musical genre
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A musical genre is how people describe different styles of music. Some of the most common music genres are:
Plus there are several more common music genres. Religious music is also common, such as hymns, choir music and many more.
To provide an example of cross genre descriptions; Joe Walsh is to The SteelDrivers as Metallica is to Trampled by Turtles. Furthermore, The Rolling Stones are to Flatt and Scruggs as Nickelback is to Doyle Lawson and Quicksilver.
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Sir Arthur Conan Doyle
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To be
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Dim sum
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Dim sum is a way of serving Chinese food. A range of different foods are served to the people who are eating, including pork wontons, fried shrimp, and egg rolls.
They are served on small wooden platters, and are usually steamed.
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Super Smash Bros. Melee
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Super Smash Bros. Melee, known in Japan as is a video game where players can choose from many people from famous Nintendo games and have them fight each other. Players can fight alone or team up with people against a friend. This game is a sequel to "Super Smash Bros." for the Nintendo 64. "Super Smash Bros. Melee" is for the Nintendo GameCube. The following game is "Super Smash Bros. Brawl" for the Wii.
Characters.
"Super Smash Bros. Melee" takes 26 characters from many of Nintendo's series. It includes all 12 veteran characters from "Super Smash Bros. 64", and adds 14 new characters, including Princess Peach and Bowser from the "Super Mario Bros." series, Princess Zelda/Sheik and Ganondorf from "The Legend of Zelda", and new characters like Ice Climbers from "Ice Climber" and Marth from "Fire Emblem". Some characters seem to play more like other characters who were in the first game, like Ganondorf compared to Captain Falcon.
Sakurai planned to include more characters, including Diddy Kong, Meta Knight, King Dedede, Balloon Fighter, Urban Champion, Ayumi Tachibana, Sonic the Hedgehog, Bubbles, Excitebike, Solid Snake, and Lucas, but did not have time to fit them in. All of them except for Balloon Fighter made it into "Super Smash Bros. Brawl".
Items.
Items from different games can fall from the sky, like Poké Balls from "Pokémon" or Mushrooms from "Mario". These items can be used in different ways. For example, Poké Balls can summon Pokémon, and Mushrooms can either grow the person whom touches it, unless it is a Poison Mushroom which makes them shrink.
Stages.
"Super Smash Bros. Melee" has many stages that players can battle on. Most of the stages are based on Nintendo series like "Mario", "Pokémon", and "The Legend of Zelda".
Tournament Play.
"Super Smash Bros. Melee" has become very popular in tournaments. These tournaments do not use items or most stages, believing that these make the game unfair. In tournaments, however, a lot of characters are not strong enough to win. Some of the best characters for tournaments are Fox McCloud, Falco Lombardi, and Jigglypuff.
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Catalysis
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Catalysis is the process of change in rate (speed) of a chemical reaction due to the help of a catalyst. Unlike other chemicals which take part in the reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in many chemical reactions. Catalysts that speed the reaction are called positive catalysts. Catalysts that slow the reaction are called negative catalysts, or inhibitors. Substances that increase the activity of catalysts are called promoters, and substances that deactivate catalysts are called catalytic poisons.
In chemistry.
A catalyst is something which changes the rate of a chemical reaction. An example is when manganese oxide (MnO2) is added to hydrogen peroxide (H2O2), and the hydrogen peroxide starts to break up into water and oxygen. Catalysts are either of natural or synthetic origin. Catalysts are useful because they leave no residue in the solution they have sped up. A catalyst can also be used in a reaction again and again as it is not used up. There are many catalysts in our body which play an important part in many biochemical reactions. These are called enzymes. Most catalysts work by lowering the 'activation energy' of a reaction. This allows less energy to be used, thus speeding up the reaction. The opposite of a catalyst is an "inhibitor". Inhibitors slow down reactions. Some of them are found in snake venom and are dangerous for our nervous system or heart.
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Hydrogen peroxide
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Hydrogen peroxide is a chemical compound. Its molecular formula is H2O2. It is used as a cleaner, and as hair bleach. In a concentration of 3% (meaning that there are 3 grams of hydrogen peroxide for 100 grams of a water solution), it can be used to treat wounds. Over time, it will slowly become oxygen gas and water through decomposition.
Chemists often use hydrogen peroxide in chemical reactions. It is a very strong oxidising agent when used with acid and water. "Oxidising agents" take electrons from other compounds.
Here hydrogen peroxide takes an electron from the ions and becomes water. The iron is oxidised (loses electrons) to the ion.
It can also be a reducing agent when used with stronger oxidisers like sodium hypochlorite. When it acts as a reducing agent, oxygen gas is also produced. "Reducing agents" give electrons to other compounds. This method is often used to make oxygen in laboratories.
Hydrogen peroxide can be bought in shops when mixed with lots of water but is very dangerous when the concentration is higher. Because it is an oxidiser, it can cause flammable materials to ignite.
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Mayotte
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Mayotte is an island in the Indian Ocean next to Madagascar.
It is geographically part of the Comoros Islands, but politically, it is part of France.
History.
In December 2024, Cyclone Chido hit Mayotte, destroying hundreds of homes, and some administrative buildings and part of the town hall in the capital Mamoudzou.
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Halldór Ásgrímsson
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Halldór Ásgrímsson (8 September 1947 – 18 May 2015) was the Prime Minister of Iceland. He became the leader of the Progressive Party in 1994. On September 15, 2004, he took over as Prime Minister from the Independence Party leader, Davíð Oddsson. He resigned in 2009.
Halldór died from a heart attack at a Reykjavik hospital, aged 67.
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Somaliland
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Somaliland (; ', '), officially the Somaliland Protectorate (, ) is a de facto country that used to be the former protectorate of British Somaliland. Djibouti lies to the west of Somaliland, the Federal Republic of Ethiopia lies to the south and west and Somalia lies to the east and south.
The area used to be the Somaliland protectorate, which was part of the British empire along with Jubaland, once called Trans-juba. The British granted its independence on 26 June 1960 upon which it called the "Somaliland Republic". Shortly after, the leaders of Somaliland and Somalia agreed to form a unified state. In May of 1991, after a brutal war waged by the government of Siad Barre, Somaliland proclaimed and regained its independence.::.
Currently, Somaliland's international position fulfills the requirements to be considered an independent country according to the Montevideo Convention. The government of Somalia, however, still considers Somaliland to be a part of Somalia.:.
Somaliland has a republican government with free elections. The capital is Hargeisa. Berbera is a beautiful city on the coast. About 55% of the people of Somalilands are nomads. Most Somalis are Sunni Muslims. Some people are part of Sufi orders.
A territory in the west, called Khatumo State has been disputed between Somaliland and Puntland.
Demographics.
Language.
Most people in Somaliland speak Somali and Arabic. Article 6 of the Constitution of 2001 says the official language of Somaliland is Somali, but Arabic is a mandatory subject in school. English is also spoken and taught in schools.
The main Somali dialect is Standard Somali. Standard Somali is spoken in most of Somalia and in countries that are next to it. Standard Somali is used by almost all of the media in the Somaliland region.
Religion.
Almost all Somalilanders are Muslims. This is because Islam is the state religion, and promoting a religion other than Islam is against the law. Small amounts of non-Islamic traditions exist in Somaliland, but Islam is very important to the Somali sense of national identity.
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NSDAP 25 points manifesto
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The NSDAP 25 points manifesto is a 25-point plan written by Anton Drexler and edited and supported by Adolf Hitler for the National Socialist German Workers' Party (NSDAP), the Nazi Party, when it was founded in 1920.
Hitler explained the purpose of the 25 points in his book "Mein Kampf". In the fifth chapter of the book's second volume, he wrote:
The manifesto in detail.
The leaders of the Party promise to work—if need be to sacrifice their very lives—to put this programme into action.
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Penny
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A penny (plural "pence" in the United Kingdom, plural "pennies" in Canada and the United States) is a coin used by several countries where people speak English. This includes United Kingdom, the United States, where a penny is worth one cent, and Canada, where "penny" is an informal term for one cent coins. Canada stopped minting the penny in 2012.
Popular Culture.
In British and American culture, finding a penny is often thought to be lucky. A popular expression is "Find a penny, pick it up, and all the day you'll have good luck." If someone asks you "A penny for your thoughts", they're wanting to know what you think. The phrase was first written in John Heywood's 1547 Dialogue Conteinying the Nomber in Effect of All the Proverbes in the Englishe Tongue, written when the penny was still a sterling silver coin. The possibly related American expression "my two cents" (meaning "my humble opinion") uses the low value of the penny to make fun of one's own thoughts in a funny way. In British English, to "spend a penny" means to urinate. The phrase does actually imply spending an actual penny: coin-operated public toilets commonly charged a predecimal penny, starting with the Great Exhibition of 1851. Around Decimal Day, British Rail introduced the "Superloo", better public toilets that charged 2p (roughly the equivalent of 6d.).
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Matt Groening
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Matthew Abram "Matt" Groening (born February 15, 1954) is an American cartoonist, screenwriter, producer, animator, author, musician, comedian, and voice actor. He is the creator of the comic strip "Life in Hell", as well as two successful television series, "The Simpsons" and "Futurama".
Groening has won 12 Primetime Emmy Awards, ten for The Simpsons and two for Futurama as well as a British Comedy Award for "outstanding contribution to comedy" in 2004. In 2002, he won the National Cartoonist Society Reuben Award for his work on Life in Hell. He received a star on the Hollywood Walk of Fame on February 14, 2012.
Early life.
He was born on February 15, 1954 in Portland, Oregon, the middle of five children. His mother Margaret Ruth was once a teacher. His father Homer Philip Groening was a filmmaker, advertiser, writer and cartoonist. Groening has Norwegian and German ancestry.
Groening grew up in Portland, and attended Ainsworth Elementary School, Lincoln High School and also The Evergreen State College in Olympia, Washington.
Personal life.
Groening identifies himself as agnostic and liberal. He has often made campaign contributions to Democratic Party candidates. His first cousin, Laurie Monnes Anderson, is a member of the Oregon State Senate representing eastern Multnomah County.
He has been married twice. Groening and Deborah Caplan married in 1986. They had 2 sons - Homer (who is called Will) and Abe. Couple split up in 1999. In 2011, Groening married Argentinian artist Agustina Picasso and became stepfather to her daughter Camille. In May 2013, Picasso gave birth to Nathaniel Philip Picasso Groening who was named after American writer Nathanael West.
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Nikolai Ivanovich Lobachevsky
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Nikolai Ivanovich Lobachevsky (, 1792–1856) was a Russian mathematician. He became known for his achievements in non-Euclidean geometry.
Biography.
Lobachevsky was born in Nizhny Novgorod, Russia. His parents were Ivan Maksimovich Lobachevsky, a clerk in a landsurveying office, and Praskovia Alexandrovna Lobachevskaya. In 1800, his father died and his mother moved to Kazan. In Kazan, Nikolai Ivanovich Lobachevsky attended Kazan Gymnasium. He graduated in 1807 and then went to Kazan University which was founded just three years earlier, in 1804.
At Kazan University, Lobachevsky was influenced by professor Johann Christian Martin Bartels (1769–1833). Bartels was a former teacher and friend of German mathematician Carl Friedrich Gauss. Lobachevsky received a Master's degree in physics and mathematics in 1811. In 1814, he became a lecturer at Kazan University, and in 1822 he became a full professor. He served in many administrative positions and was the rector of Kazan University from 1827 to 1846. He retired (or was dismissed) in 1846. After this event his health rapidly deteriorated. In addition to teaching mathematics and physics at Kazan University Lobachevsky also was an astronomy teacher there.
In 1832, he married Varvara Alexivna Moisieva. They had seven children.
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Wildebeest
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A wildebeest (or gnu) is an animal. It is a large hoofed mammal in the Bovidae family. There are two species of wildebeest. Both live in Africa.
Size.
Wildebeest grow to 1.15 to 1.40 metres (at the shoulder) and they weigh between 150 and 250 kilograms when they are fully grown. They live in the plains and open woodlands in southern Africa. The biggest herds can be found in the Serengeti. Wildebeest can live for more than 20 years.
What they eat.
Like other members of the same family (antelopes, deer and goats, amongst others), they mainly eat grass. But since in the African grasslands, there is not always grass, wildebeest are forced to migrate to find food all year round. In May, about 1.5 million animals move from the grasslands to the woods. In November they move back; there is grass in the plains in summer.
Breeding and mating season.
The cows (female Gnus) will calve (give birth to the young) in summer in the plains. After the females have given birth, the breeding season begins. The dominant males mark off (and defend) some territory. They do this with feces, and with scent.
Wildebeest are an important part of the ecosystem. With their feces, they fertilize the ground, and their trampling is good for new growth. They also provide food for predators, like lions leopards, cheetahs, and hyenas African wild dogs, they migration Nile crocodiles.
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Gnu or GNU may mean:
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Serengeti
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The Serengeti (also Seremgeti) is a region of savannah (woodlands and grasslands) in East Africa. The south of it (80%) belongs to Tanzania. The north of it is in Kenya. It is about 30,000 square kilometers, and one of the greatest areas for wildlife.
It has more than 1.6 million herbivores and thousands of predators. Wildebeests, gazelles, zebras and buffalos are the most common animals in the region.
This area is most famous for the migration that takes place every year.
Every year around October nearly 1.5 million herbivores travel towards the southern plains, crossing the Mara River, from the northern hills for the rains. And then back to the north through the west, once again crossing the Mara river, after the rains in around April. This phenomenon is sometimes also called the Circular Migration.
Also in this area is the archeologically significant Olduvai Gorge where some of the oldest hominid fossils are found.
The Serengeti region contains the Serengeti National Park, the Ngorongoro Conservation Area and Maswa Game Reserve in Tanzania and the Maasai Mara National Reserve in Kenya.
Serengeti National Park.
Geography.
The park covers 14,763 km² (5,700 square miles) of grassland plains and savanna as well as riverine forest and woodlands. The park is in the north of the country, bordered to the north by the national Tanzania and Kenyan border, where it is continuous with the Masai Mara National Reserve. To the southeast of the park is Ngorongoro Conservation Area, to the southwest is Maswa Game Reserve, and to the western borders are Ikorongo and Grumeti Game Reserves, to the northeast is Loliondo Game Control Area.
Few people are allowed to live in the National Park. Exceptions the staff of the Park, researchers and staff of Frankfurt Zoological Society, and staff of the various lodges and hotels. The main settlement is at Seronera.
The park has three regions:
Wildlife.
As well as the migration of ungulates, the park has a healthy stock of other resident wildlife, especially the "Big Five":
The park also supports many further species, including cheetah, Thomson's and Grant's gazelle, topi, eland, water buck, hyena, baboon, impala, African wild dog and giraffe. The park also boasts about 500 bird species, including ostrich, secretary bird, Kori bustard, crowned crane, marabou stork, martial eagle, lovebirds and many species of vultures.
Ngorongoro Conservation Area.
Ngorongoro is the caldera of a huge extinct volcano, which is part of the Serengeti area.
The Ngorongoro Conservation Area (NCA) is a UNESCO World Heritage Site 180 km (112 miles) west of Arusha in the Crater Highlands area of Tanzania.
Ngorongoro Crater.
The main feature of the NCA is the Ngorongoro Crater, a large volcanic caldera. The crater, which formed when a giant volcano exploded and collapsed on itself some two to three million years ago, is deep and its floor covers .
Estimates of the height of the original volcano range from fifteen to nineteen thousand feet (4500 to 5800 metres) high.
Although thought of as "a natural enclosure" for a very wide variety of wildlife, up to 20% or more of the wildebeest ("Connochaetes taurinus") and half the zebra ("Equus burchelli") populations leave the Crater in the wet season. The Ngorongoro lions are significantly inbred, with many genetic problems passed from generation to generation. This is due to the very few new bloodlines that enter the local gene pool, because few migrating male lions enter the crater from the outside. Those who do enter the crater often cannot contribute to the gene pool. The crater's male lions, because of their large size (the result of an abundant food source), easily expel outside competitors.
Animal populations in the crater include most of the species in East Africa, but there are no impalas ("Aepyceros melampus"), giraffes ("Giraffa camelopardalis"), or crocodiles ("Crocodylus niloticus").
The crater highlands on the side facing the easterly trade winds receives 800–1200 mm of rain a year and is covered largely in montane forest, while the less-steep west wall receives only 400–600 mm; this side is grassland and bushland dotted with Euphorbia bussei trees. The crater floor is mostly open grassland with two small wooded areas dominated by "Acacia xanthophloea".
The Munge Stream drains Olmoti Crater to the north, and is the main water source draining into the seasonal salt lake in the center of the crater. This lake is known by two names: "Makat" as the Maasai called it, meaning salt; and "Magadi". The Lerai Stream drains the humid forests to the south of the Crater, and it feeds the Lerai Forest on the crater floor - when there is enough rain, the Lerai drains into Lake Magadi as well. Extraction of water by lodges and NCA headquarters reduces the amount of water entering Lerai by around 25%.
The other major water source in the crater is the Ngoitokitok Spring, near the eastern crater wall. There is a picnic site here open to tourists and a huge swamp fed by the spring, and the area is inhabited by hippopotamus, elephants, lions, and many others. Many other small springs are around the crater's floor, and these are important water supplies for the animals and local Masaai, especially during times of drought.
Aside from herds of zebra, gazelle, and wildebeest, the crater is home to the "Big Five Game" of rhinoceros, lion, leopard, elephant, and buffalo. The crater plays host to almost every individual species of wildlife in East Africa, with an estimated 25 000 animals within the crater.
Following the recommendations of a committee of scientists after the 2000 drought, an ecological burning program was implemented in the crater, which entails annual or biannual controlled burns of up to 20% of the grasslands. Maasai are now permitted to graze their cattle within the crater, but must enter and exit daily.
Olduvai Gorge.
The conservation area also protects Olduvai Gorge, in the plains area. It is considered the seat of humanity after the discovery of the earliest known specimens of the human genus, "Homo habilis " as well as early hominidae, such as "Paranthropus boisei".
The Olduvai Gorge or Oldupai Gorge is a steep-sided ravine in the Great Rift Valley, which stretches along eastern Africa. Olduvai is in the eastern Serengeti Plains in northern Tanzania and is about thirty miles long. It is in the rain shadow of the Ngorongoro highlands and is the driest part of the region.
It is one of the most important prehistoric sites in the world. Research there has greatly developed our understanding of early human evolution. Excavation work there was pioneered by Mary and Louis Leakey in the 1950s. It is still continued today by their family. During the Pleistocene, the site was that of a large lake, the shores of which were covered with successive deposits of volcanic ash. Around 500,000 years ago seismic activity diverted a nearby stream which began to cut down into the sediments, revealing seven main layers in the walls of the gorge.
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Spider
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Spiders (class Arachnida, order Araneae) are air-breathing arthropods. They have eight legs, and mouthparts (chelicerae) with fangs that inject venom. Most make silk. The spiders are seventh in number of species of all animal orders. About 53,000 spider species, and 136 families have been recorded by taxonomists. Over twenty different classifications have been proposed since 1900.p3
Spiders live on every continent except for Antarctica, and in nearly every habitat with the exceptions of air and sea.
Almost all spiders are predators, and most eat insects. They catch their prey in several ways. Some build a spider web, and some use a thread of silk that they throw at the insect. Some kinds of spiders hide in holes in the ground, then run out and grab an insect that walks by. Others will make web 'nets' to throw at passing insects. Or they go out and simply attack their prey. Some can jump quite well and hunt by sneaking close to an insect and then jumping on it.
Anatomy.
Spiders have a two-part body, the front part (cephalothorax) and the abdomen. Unlike insects, spiders do not have antennae. The more advanced spiders have a centralized nervous system, with their ganglia fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs, and extend them by hydraulic pressure.
Size range.
The smallest of full-grown spiders can be less than 4 mm. (0.1 inch). The largest of spiders can have a body length of 10 cm. (4 inches) or more. The largest can weigh 150 grams (5.3 oz). The largest of spiders are the tarantulas and the huntsman spiders. Some huntsman spiders in South East Asia can have a leg span of around 250–300 mm (9.8–11.8 in).
Spider eyes and other senses.
Most spiders have four pairs of eyes on the top-front area of the body, arranged in patterns that vary from one family to another. The main eyes at the front are capable of forming images. Jumping spiders have visual acuity which is ten times better than that of dragonflies, which have by far the best vision among insects. The spiders do this by a telephoto-like series of lenses, a four-layered retina. They can swivel their eyes and put together images from different stages in the scan. The downside is that the scanning and integrating processes are relatively slow.
Spiders and other arthropods have modified their cuticles into elaborate arrays of sensors. Various sensors, mostly bristles, respond to touch, from strong contact to very weak air currents. Chemical sensors provide equivalents of taste and smell. Spiders also have in the joints of their limbs sensors that detect forces and vibrations. In web-building spiders all these mechanical and chemical sensors are more important than the eyes. The eyes are more important to spiders that hunt actively. Like most arthropods, spiders lack balance sensors, and rely on their eyes to tell them which way is up.
Fangs.
The fangs are hollow, like the needles used to give injections. Spiders use their fangs to inject toxins that kill the insects they will eat. Some kinds of spider venom attack the nervous systems of their prey, and other kinds of venom attack body tissues.
Behavior.
What most spiders eat.
Spiders are predators, and eat insects and other arthropods (including other spiders). Most use venom from their fangs to kill their prey. It is rare for spiders to capture prey that are much larger than they are. It is also difficult for most spiders to capture prey that are very much smaller than they are. There are some spiders that form colonies. Spiders eat not only spiders of other species, but spiders of their own species.
The black widow spider got its name because the females sometimes eat the males that mate with them. This may also happen in other species. Each species of spider has its own way of communicating with other spiders they meet. Because of the danger of being eaten, in some species the males have special hooks on their front legs with which they hold the female while they mate. Others bring the female something to eat. There are a few species in which the male spiders construct their own little webs that are connected to the webs of the females. In these species, the male is so much smaller than the female that it would be difficult for her to actually capture the male.
Most spiders have such poor vision that they will not even notice a dead insect. Jumping spiders are one exception to this rule. They have such good vision that they can find recently dead flies or other insects to eat.
Some spiders are not predators.
Spiders are basically predators, but some have other food sources. The jumping spider "Bagheera kiplingi" gets over 90% of its food from fairly solid plant material produced by acacias as part of a beneficial relationship with a species of ant.
Young spiders of several families feed on plant nectar. Studies have shown that they do this for long periods. They also clean themselves regularly while feeding. These spiders also prefer sugar solutions to plain water, which shows that they are looking for nutrients. Many spiders are nocturnal, they are most active during the night. The extent of nectar consumption by spiders may therefore have been under-estimated. Nectar contains amino acids, lipids, vitamins and minerals in addition to sugars. Studies have shown that other spider species live longer when nectar is available. Feeding on nectar also avoids the risks of struggles with prey, and the costs of producing venom and digestive enzymes. Since nectar is a flowering plant production, its consumption by spiders came quite late in their evolution.
Various species are known to feed on dead arthropods (scavenging), web silk, and their own shed exoskeletons. Pollen caught in webs may also be eaten, and studies have shown that young spiders have a better chance of survival if they have the opportunity to eat pollen. In captivity, several spider species are also known to feed on bananas, marmalade, milk, egg yolk and sausages.
Methods of catching prey.
Webs.
The best-known method spiders use to capture prey is a sticky web. The placing of the web allows different spiders to trap different insects in the same area. Flat, horizontal webs allow them to trap insects that fly up from vegetation underneath, for example. Flat vertical nets allow them to trap insects in flight. The spiders that build webs usually do not see very well, but they are very sensitive to vibrations.
Underwater.
Females of the water spider "Argyroneta aquatica" build underwater "diving bell" webs which they fill with air and use while eating their prey, molting, mating, and raising offspring. They live almost entirely within the bells, darting out to catch prey animals that touch the bell or the threads that anchor it. A few spiders use the surfaces of lakes and ponds as "webs", detecting trapped insects by the vibrations that these cause while struggling.
Bola casting.
Net-casting spiders weave only small webs but then manipulate them to trap prey. They stretch their webs and then release them when prey strike them. Those of the family Deinopidae weave even smaller webs, hold them outstretched between their first two pairs of legs, and lunge and push the webs as much as twice their own body length to trap prey, and this move may increase the webs' area by a factor of up to ten. Experiments have shown that "Deinopis spinosus" has two different techniques for trapping prey: backwards strikes to catch flying insects, whose vibrations it detects; and forward strikes to catch ground-walking prey that it sees. These two techniques have also been observed in other deinopids. Walking insects form most of the prey of most deinopids, but one population of "Deinopis subrufus" appears to live mainly on tipulid flies that they catch with the backwards strike.
Mature female bolas spiders of the genus "Mastophora" build "webs" that consist of only a single "trapeze line", which they patrol. They also construct a bolas made of a single thread, tipped with a large ball of very wet sticky silk. They emit chemicals that resemble the pheromones of moths, and then swing the bolas at the moths. They catch about the same weight of insects per night as web-weaving spiders of similar size. The spiders eat the bolas if they have not made a kill in about 30 minutes, rest for a while, and then make new bolas. Juveniles and adult males are much smaller and do not make bolas. Instead they release different pheromones that attract moth flies, and catch them with their front pairs of legs.
Using trapdoors.
The primitive Liphistiidae, the "trapdoor spiders" (family Ctenizidae) and many tarantulas are ambush predators. They lurk in burrows, often closed by trapdoors and surrounded by networks of silk threads that alert these spiders to the presence of prey. Other ambush predators do without such aids, including many crab spiders. A few species that prey on bees, which see ultraviolet, can adjust their ultraviolet reflectance to match the flowers in which they are lurking. Wolf spiders, jumping spiders, fishing spiders and some crab spiders capture prey by chasing it, and rely mainly on vision to get their prey.
Capturing insects without using webs.
Not all spiders use silk to net their prey. Instead, these spiders may capture insects by grabbing them and then biting them. Among these kinds of spiders the two best known are the wolf spiders and the jumping spiders.
Wolf spiders.
A wolf spider will usually wait until an insect comes near to it, and then rush at the insect, grab it using its front legs, and then bite the insect so that its venom can do its work.
Female wolf spiders lay their eggs on a pad of silk and then draw the edges together to create a round ball that they carry along with them wherever they go. They hold their egg balls to their tail ends by using their silk. When the eggs hatch, the little spiders will crawl onto the mother's back, and she will carry them along with her for days or weeks.
Wolf spiders are very good mothers and will strongly protect both their egg balls and their infants. When the time comes, the little spiders will leave the mother and each will go its own way.
Jumping spiders.
Jumping spiders have very good eyes and can see well. They sneak as close to an insect as they can, and then they jump onto the insect and immediately bite it. Since they often hunt in trees, bushes, and on the sides of walls, if the jumping spider misses it may fall off. But they have a way to save themselves from harm. Before they jump they fasten their silk to the place where they have been standing, and as they jump they let out a silk safety line. So if they fall they will catch themselves when they reach the end of their silk safety line. Sometimes a jumping spider will catch an insect and then fall while still holding onto the insect. But the spider is still safe.
Jumping spiders make little silken "tents" for themselves to sleep in. When they lay eggs they keep them inside such a shelter. They do not take their eggs with them when they go out to hunt.
For all male spiders it is dangerous to seek a mate. The female spider may not realize that the male is a spider of her kind, so she may try to eat it. The jumping spiders not only have visual patterns that identify them to each other, but the male jumping spider will do a special dance when it approaches a female of the same species. That way, the female can recognize that it is a male of her species. She will generally forget about eating for long enough to mate with the visiting male spider.
Jumping spiders have such good eyes that they will usually watch any human who tries to watch them. Some species are very shy and will run away if the human gets too close. But some species, such as "Phidippus audax" (the audacious or brave jumping spider) and "Platycryptus undatus", can become calm if the human comes close to them slowly. Sometimes they will jump onto one of your fingers and then jump from finger to finger and from hand to hand. They seem to want to explore.
Hunting other spiders.
Some jumping spiders of the genus "Portia" hunt other spiders in ways that seem intelligent, outflanking their victims or luring them from their webs. Laboratory studies show that "Portia"'s instinctive tactics are only starting points for a trial-and-error approach from which these spiders learn very quickly how to overcome new prey species. However, they seem to be relatively slow thinkers, which is not surprising as their brains are vastly smaller than those of mammalian predators.
Disguising as ants.
Ant-mimicking spiders face several challenges: they generally develop slimmer abdomens and false "waists" to mimic the three distinct regions (tagmata) of an ant's body; they wave the first pair of legs in form to their heads to mimic antennae, which spiders lack, and to conceal the fact that they have eight legs rather than six. They have large color patches round one pair of eyes to disguise the fact that they generally have eight simple eyes, while ants have two compound eyes; they cover their bodies with reflective hairs to resemble the shiny bodies of ants. In some spider species males and females mimic different ant species, as female spiders are usually much larger than males.
Ant-mimicking spiders also modify their behavior to resemble that of the target species of ant, for example many adopt a zig-zag pattern of movement, ant-mimicking jumping spiders avoid jumping, and spiders of the genus "Synemosyna" walk on the outer edges of leaves in the same way as "Pseudomyrmex". Ant-mimicry in many spiders and other arthropods may be for protection from predators that hunt by sight, including birds, lizards and spiders. However several ant-mimicking spiders prey either on ants or on the ants "livestock" such as aphids. When at rest the ant-mimicking crab spider "Amyciaea" does not closely resemble "Oecophylla", but while hunting it imitates the behavior of a dying ant to attract worker ants. After a kill some ant-mimicking spiders hold their victims between themselves and large groups of ants to avoid being attacked.
Reproduction and life cycle.
Spiders reproduce sexually and fertilization is internal but indirect. In other words, the sperm is not inserted into the female's body by the male's genitals but by an intermediate stage. Unlike many land-living arthropods, male spiders do not produce ready-made spermatophores (packages of sperm). Instead, they spin small sperm webs on to which they ejaculate and then transfer the sperm to structures on the tips of their pedipalps. When a male detects signs of a female nearby he checks whether she is of the same species and whether she is ready to mate; for example in species that produce webs or 'safety ropes', the male can identify the species and sex of these objects by smell.
Spiders generally use elaborate courtship rituals to prevent the large females from eating the small males before fertilization, except where the male is so much smaller that he is not worth eating. In some species males mate with newly molted females, which are too weak to be dangerous to the males.
In web-weaving species precise patterns of vibrations in the web are a major part of the rituals, while patterns of touches on the female's body are important in many spiders that hunt actively, and may 'hypnotize' the female. Gestures and dances by the male are important for jumping spiders, which have excellent eyesight. If courtship is successful, the male injects his sperm from the pedipalps into the female's genital opening on the underside of her abdomen. Female reproductive tracts vary. Some are simple tubes, but others have chambers where females store sperm, and release it when they are ready.
Males do get eaten in some species. Males of the genus "Tidarren" cut off one of their palps, and enter adult life with one palp only. The palps are 20% of male's body mass in this species, and detaching one of the two improves mobility. In the Yemeni species "Tidarren argo", the remaining palp is then torn off by the female. The separated palp remains attached to the female's opening for about four hours. In the meantime, the female feeds on the palpless male. In over 60% of cases the female of the Australian redback spider kills and eats the male after it inserts its second palp into the female's genital opening; in fact the males co-operate by trying to impale themselves on the females' fangs. Observation shows that most male redbacks never get an opportunity to mate, and the 'lucky' ones increase the likely number of offspring by ensuring that the females are well-fed. However males of most species survive a few matings, limited mainly by their short life spans. Some even live for a while in their mates' webs.p176/212
Females lay up to 3,000 eggs in one or more silk egg sacs, which maintain a fairly constant humidity level. In some species the females die afterwards, but females of other species protect the sacs by attaching them to their webs, hiding them in nests, carrying them in the chelicerae or attaching them to the spinnerets and dragging them along.
Development of young.
Baby spiders pass all their larval stages inside the egg and hatch as spiderlings, very small and sexually immature but similar in shape to adults. Some spiders care for their young, for example a wolf spider's brood cling to rough bristles on the mother's back, and females of some species respond to the "begging" behaviour of their young by giving them their prey, provided it is no longer struggling, or even regurgitate food.
Like other arthropods, spiders have to moult to grow as their cuticle ("skin") cannot stretch. Most spiders live for only one to two years, although some tarantulas can live in captivity for over 20 years.p232
Spiders and humans.
Of the 40,000 spiders, less than 12 are known to be dangerous to humans. Most of the time, being bitten by a spider is painful. Most spiders use venom to paralyse their prey; they kill it through eating, or through a bite. A few spiders have venoms that can be dangerous to weakened people and those allergic to it. Since 1927, 13 people have died, after a bite from a "Atrax robustus" spider from Australia.
The spider that kills the most people, the black widow and other spiders in the genus "Latrodectus" are around 1 cm. in body length. The "Atrax" and "Phoneutria" spiders, which are also capable of killing people, both average around 2.5 cm. or one inch, and even the Widow spiders are large enough to be easily noticed.
Even relatively small spiders like "Phidippus audax" can give a painful bite if you hurt them, but spiders are very helpful to human beings because they control insects that eat our crops.
Being afraid of spiders is a very common phobia (fear). The widow spiders (black widows and other members of their genus) never willingly leave their webs, so usually people get bitten when they touch the spider by mistake.
Gallery.
Click on a picture to see it larger:
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The 1760s was a decade that began on 1 January 1760 and ended on 31 December 1769. It is distinct from the decade known as the 177th decade which began on January 1, 1761 and ended on December 31, 1770.
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Grass
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Grass is a type of plant with narrow leaves growing from the base. Their appearance as a common plant was in the mid-Cretaceous period. There are 12,000 species now.
Much grass is used to cover the ground in places such as lawns and parks. Grass is usually the color green. That is because they are pollinated by wind rather than insect pollinators, so they do not have to attract insects. Green is the best color for photosynthesis.
Grasslands such as savanna and prairie are where grasses are dominant. They cover 40,5% of the land area of the Earth, but not Greenland nor Antarctica.
Grasses are monocotyledon herbaceous plants. They include the "grass" of the family Poaceae, which are called grass by ordinary people. This family is also called the Gramineae and includes some of the sedges (Cyperaceae) and the rushes (Juncaceae). These three families are not very closely related, though all of them belong to clades in the order Poales. They are similar adaptations to a similar life-style.
With about 780 genera and about 12,000 species, the Poaceae is the fifth-largest plant family. Only the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae have more species.
The true grasses include cereals, bamboo and the grasses of lawns (turf) and grassland. Uses for graminoids include food (as grain, shoots or rhizomes), drink (beer, whisky), pasture for livestock, thatch, paper, fuel, clothing, insulation, construction, basket weaving and many others.
Many grasses are short, but some grasses can grow tall, such as bamboo. Plants from the grass family can grow in many places and make grasslands, including areas that are very dry or cold. There are several other plants that look similar to grass and are referred to as such but are not members of the grass family. These plants include rushes, reeds, papyrus and water chestnut. Seagrass is a monocot in the order "Alismatales".
Grasses are an important food for many animals, such as deer, buffalo, cattle, mice, grasshoppers, caterpillars and many other grazers. Unlike other plants, grasses grow from the bottom, so when animals eat grass, they usually do not destroy the part that grows. This is part of the reason why the plants are so successful.
Without grass, more soil might wash away into rivers (erosion).
Evolution of grass.
Grasses include some of the most versatile plant life-forms. They became widespread toward the end of the Cretaceous. Fossilized dinosaur dung (coprolites) have been found containing grass phytoliths (silica stones inside grass leaves). Grasses have adapted to conditions in lush rain forests, dry deserts, cold mountains and even intertidal habitats, and are now the most widespread plant type. Grass is a valuable source of food and energy for many animals.
Grass and people.
Lawn grass is often planted on sports fields and in the area around a building. Sometimes chemicals and water is used to help lawns to grow.
People have used grasses for a long time. People eat parts of grasses. Corn, wheat, barley, oats, rice and millet are cereals, common grains whose seeds are used for food and to make alcohol such as beer.
Sugar comes from sugar cane, which is also a plant in the grass family. People have grown grasses as food for farm animals for about 4,000 years. People use bamboo to build houses, fences, furniture and other things. Grass plants can also be used as fuel, to cover rooves, and to weave baskets.
Language.
In English, the word "grass" appears in several phrases. For example:
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Cacao tree
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The cacao tree is a small tree originally grown in tropical South America. It only grows to 4 to 8 meters in height. Its seeds are called cocoa and are used to produce cocoa butter, chocolate drinks, and chocolate. Now the trees are grown in plantations in many tropical countries.
Cultivation.
Cacao is planted on over 70000 square kilometres worldwide with 40% of production coming from Côte d'Ivoire, Ghana, and Indonesia. Each country produces about 15%, with smaller amounts coming from Brazil, Nigeria, and Cameroon.
A tree begins to bear fruit when it is 4 or 5 years old. In one year, when mature, it may have 6,000 flowers, but only about 20 pods. About 300-600 seeds (10 pods) are required to produce around 1 kg of cocoa paste.
There are three main cultivar groups of cacao beans used to make cocoa and chocolate. The most prized, rare, and expensive is the Criollo Group, the cocoa bean used by the Maya. Only 10% of chocolate is made from the Criollo, which is less bitter and more aromatic than any other bean. The cacao bean in 80% of chocolate is made using beans of the Forastero Group. Forastero trees are significantly hardier than Criollo trees, resulting in cheaper cacao beans. Trinitario, a hybrid of Criollo and Forastero, is used in about 10% of chocolate. For details of processing, see cocoa.
Cacao beans were commonly used as currency in Pre-Columbian Mesoamerica. In some areas, such as Yucatán, they were still used in place of small coins as late as the 1840s.
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Mahabad
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Mahabad and Piranshahr (, ); (Old name: سابلاخ: Sablakh, which may be of Mongolian origin) is a city in Iran. It is in the north-west of the country, in the region of Iranian Kurdistan and the province of West Azarbaijan. The city is south of Lake Urmia in a narrow valley 1,300 metres above sea level. There are about 162.434 people who live in the city. Mahabad is connected by road with Tabriz 300 km north, Urmia 150 km north and Arbil, in Iraqi Kurdistan.
The city is one center and symbol of the Kurdish nationalism. The reason is because in 1945 it was the capital of the newly founded people's Republic of Mahabad. The republic was conquered by Iranian forces on 16 December 1946. The president was Qazi Muhammad. The majority of the population is Kurdish. During the revolution in Iran, on 3 September 1979 the city was bombed and occupied by Iranian forces. After the death of Shivan Qaderi, a student and opposition activist in July 9 2005, the Kurdish population protested against the Iranian government.
Mahabad also a branch of the Islamic Azad University.
The region of Mukrian consists of Piranshahr and Mahabad.
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Shivan Qaderi
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Shivan Qaderi (or Sivan Ghaderi or Schuaneh Ghaderi; died 9 July 2005 in Mahabad) was a student and opposition activist in Iran. After his death in 2005, the Kurds protested and the Iranian government had to send more than 100,000 soldiers to this region. The Kurdistan Democratic Party of Iran reported, that about 50,000 people had protested after his death on the Chuwarchira Square. Humans Rights First say that, after he was shot, Iranian soldiers tied Ghaderi's body "to a military vehicle and dragged it through the city, obviously trying to frighten the population so that they would not organize any more protests."
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Shining Path
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Sauce
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In cooking, a sauce is a liquid mixture added to another food for flavour. Sauces are not normally eaten by themselves; they add flavour, moisture, and visual appeal to another dish. Sauces are an essential element in cuisines all over the world.
The main sauces of French cuisine are built on a basis of roux, which is just flour and the liquid part of butter. Examples from Italian cuisine are the egg, cheese and ham sauce called "Carbonara"; the ground meat sauce called "bolognese", and the herbs and garlic sauce called "pesto".
Bottled sauces can be poured over food when it is served. An example would be the tomato-based sauce that is usually poured over spaghetti. Gravy is a brown sauce served with meat.
"Sauce" is a French word taken from the Latin "salsus", meaning "salted". Possibly the oldest sauce recorded is "garum", the fish sauce used by the Romans.
Sauces need a liquid component, but some sauces (for example, pico de gallo salsa or chutney) may contain more solid elements than liquid.
Sauces may be used for savoury dishes or for desserts. They can be prepared and served cold, like mayonnaise, prepared cold but served lukewarm like pesto, or can be cooked like bechamel and served warm or again cooked and served cold like apple sauce.
Some sauces are commercial products like Worcestershire sauce, HP sauce, soy sauce or ketchup. In French cuisine they are freshly prepared by the chef. Sauces for salads are called salad dressing. A cook who specializes in making sauces is a saucier.
French cuisine.
Sauces in French cuisine date back to the Middle Ages. There were hundreds of sauces in the culinary repertoire, and were a major defining characteristic of French cooking of the 19th and 20th centuries, until nouvelle cuisine.
In the 19th century, the chef Antonin Carême classified sauces into four families, each of which was based on a mother sauce (Also called "grandes sauces"). Carême's four mother sauces were:
In the early 20th century, the chef Auguste Escoffier updated this classification to five mother sauces. They are:
A sauce which is based on one of the mother sauces is sometimes called a small sauce, minor sauce, or secondary sauce. Most sauces commonly used in classical cuisine are small sauces, or derivatives of one of the above-mentioned mother sauces.
Mother sauces are not commonly served as they are; instead they are augmented with additional ingredients to make small (derivative) sauces. For example, Bechamel can be made into Mornay by the addition of Gruyère or any cheese one may like, and Espagnole becomes Bordelaise with the addition and reduction of red wine, shallots, and poached beef marrow.
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Spaghetti
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Spaghetti is a long, string-shaped kind of pasta.
The word was first used in 1824 in the work "Li maccheroni di Napoli" by . A single strand of spaghetti is called a , which means "short/little string" in Italian.
Spaghetti is made from wheat noodles, which are boiled in water for a short time. Spaghetti can either be served as a side dish, or as a main dish. Most commonly, a sauce is added. There are many different kinds of sauces. Simpler ones are made of butter, more complicated ones include tomatos, garlic, olive oil and various other herbs. Different varieties with mussels, fish or meat also exist. Ground parmesan cheese is often added.
In Italy, the sauce is usually mixed with the spaghetti while they are being prepared. Usually, spaghetti is eaten only with a fork, or with a fork and a spoon. Sometimes, they are cut with a knife for small children. Many Italians see using a knife to eat spaghetti as bad manners, except to prepare them for small children.
In the United States, there is a kind of spaghetti called "Alvaro's spaghetti" which is served with alfredo sauce. In some countries, like United States or Canada, meatballs are often in the spaghetti sauce.
In China, spaghetti is often made by hand. In Italy, spaghetti is made with a machine so that large amounts can be made quickly. Italy is the biggest producer and consumer of spaghetti in the world.
It is also a popular dish in Libya.
Spaghetti is called by other words when it has a different thickness: "spaghettini (n. 3)" (which means "little spaghetti"), "spaghetti (n. 5)", and "spaghettoni (n. 8)" (which means "big spaghetti").
Usually, spaghetti leftovers last in a fridge for around 3 to 5 days, while spaghetti in a freezer will last more than one month.
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Emperor penguin
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The Emperor penguin ("Aptenodytes forsteri") is a penguin that lives in Antarctica. It is the tallest and heaviest penguin. They are the only birds that can lay their eggs on ice.
Emperors are the biggest of the 18 species of penguin found today, and one of the largest of all birds. Emperor penguins are about tall, weigh up to and have a wingspan of . Emperor Penguins are black and white like all penguins, and the sides of their neck and chest are golden. They can dive deeper than any other bird, including other penguins. Emperor penguins are also the largest penguins in the world. Emperors are the biggest of the 18 species of penguin found today and one of the largest of all birds. There are approximately 595,000 adult Emperor penguins in Antarctica. Emperor penguins do not build nests they lay their eggs on the ice through their legs. Like other penguins, emperors leap into the air while swimming, which is called porpoising.
Life.
They eat mostly crustaceans, such as krill, and fish but also eat cephalopods, such as squid, cuttlefish, and octopuses.
Emperors live in the coldest climate on earth. Temperatures can drop as low as -140 degrees Fahrenheit (-95.6 °C) on the Antarctic ice. They breed at the beginning of the Antarctic winter (March and April), on the ice all around the Antarctic continent. They live in large groups, called colonies, that can have up to 20,000 birds. They huddle close together to keep warm. Emperor penguins live for about 20 years, although some have been known to live for 40 years. They dive at their food and they stay in small groups
The shape of their body helps them to survive. They have short wings that help them swim and to dive up to to catch larger fish. The deepest dive recorded is . They can swim up to for a short time, which lets them escape their main enemy, the leopard seal. They can stay warm because they have a thick layer of blubber. The layer of downy feathers trap air that keeps the body heat in and cold air and water out. They also have large amounts of body oil that help in keeping them dry in the water.
While they are very fast in the water, on land the birds can only walk very slowly. On ice they can lie on their stomachs and use their wings to slide along, like a sled.
Breeding.
Emperor penguins spend most of their time in the water, coming to the shore to breed. There is nothing on the ice to make a nest, so after the female lays her one egg in winter, the male puts the egg on his feet to keep it warm until spring. This can be from 65 to 75 days. He has a special fold of skin on his stomach which can fold over and cover the egg to keep it warm. This is a difficult action to swap the egg from the female to the male; if it sits for too long on the ice it will freeze. He does not eat during this time, and can lose up to half his weight. To keep warm, all the male penguins huddle together. Those on the outside of the group will slowly shuffle their way into the middle; the group is always moving and can move as much as in 24 hours. The female comes back in spring when the egg hatches, while the male will go back to sea to eat, but comes back to help look after the chick. The chick lives on its parents feet for about 50 days until it becomes strong enough to survive the cold.
Research.
Regarding the number of these penguins, in the world:
As of 2025, "A new analysis of [... pictures taken from satellites, is saying that maybe the number of emperor penguins, has become smaller or] declined 22% over a 15-year period ([year] 2009 to 2024) in a key sector of the continent – [including completely, or] encompassing the Antarctic Peninsula, Weddell Sea and Bellingshausen Sea", according to the British Antarctic Survey. Publication was done in .
Movies.
The Australian movie "Happy Feet" was based on the story of an emperor penguin who is unable to sing and get a mate because he was left for too long on the ice when still an egg.
The documentary "March of the Penguins" is about emperor penguins moving across the ice to lay eggs.
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Snares penguin
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The Snares penguin ("Eudyptes robustus"), is a crested penguin. It is probably a subspecies of the Fiordland penguin. It is a penguin from New Zealand. It is between 50 and 70 centimetres in height and weighs between 2.5 and 4 kilograms.
It breeds on The Snares, a small island group south of New Zealand's South Island.
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Spaghetti Westerns
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Chahar Cheragh Square
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Chuar-chira Square (, ) (meaning "Square of the four candles"), is a known square in center of city of Mahabad where after Iranian invasion in 1947, Qazi Muhammad the president of Republic of Mahabad was hanged in public as well as other leaders of the republic in Mahabad and Bukan. In 2005 the Kurdistan Democratic Party of Iran reported that about 50.000 persons had demonstrated against the Iranian gouverment. The reason was the death of Shivan Qaderi.
It is now officially called Shardari Square. This square is one of the oldest places of Mahabad city.
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Complex number
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A complex number is a number, but is different from common numbers in many ways. A complex number is made up using two numbers combined. The first part is a real number, and the second part is an imaginary number. The most important imaginary number is called formula_1, defined as a number that will be -1 when squared ("squared" means "multiplied by itself"): formula_2. All other imaginary numbers are formula_1 multiplied by a real number, in the same way that all real numbers can be thought of as 1 multiplied by another number. Arithmetic functions such as addition, subtraction, multiplication, and division can also be performed with complex numbers. They follow commutative, associative and distributive properties, just like real numbers. The set of complex numbers is often represented using the symbol formula_4.
Complex numbers were discovered while attempting to solve special equations that have exponents in them. These equations began to pose problems for mathematicians. As a comparison, using negative numbers, it is possible to find the "x" in the equation formula_5 for all real values of "a" and "b", but if only positive numbers are allowed for "x", it is sometimes impossible to find a positive "x", as in the equation formula_6.
With exponentiation, there is a difficulty to be overcome. There is no real number that gives −1 when it is squared. In other words, −1 (or any other negative number) has no real square root. For example, there is no real number formula_7 that solves the equation formula_8. To solve this problem, mathematicians introduced a symbol "i" (I representing the square root of -1) and called it the "imaginary unit". This is the imaginary number that will give −1 when it is squared.
The first mathematicians to have thought of this were probably Gerolamo Cardano and Rafael Bombelli. They lived in the 16th century. It was probably Leonhard Euler who introduced writing formula_9 for that number.
All complex numbers can be written as formula_10 (or formula_11), where "a" is called the "real part" of the number, and "b" is called the "imaginary part". We write formula_12 or formula_13 for the real part of a complex number formula_14. So, if formula_15, we write formula_16. Similarly, we write formula_17 or formula_18 for the imaginary part of a complex number formula_14; formula_20, for the same . Every real number is also a complex number; it is a complex number with formula_21.
A complex number can also be written as an ordered pair formula_22, where both "a" and "b" are real numbers. Any real number can simply be written as formula_23, or as the pair formula_24.
Sometimes, formula_25 is written instead of formula_1. In electrical engineering for instance, formula_1 means electric current so j is used instead of formula_1, to avoid confusion as some complex numbers are often utilised in electrical engineering.
Operations over complex numbers.
Addition, subtraction, multiplication and exponentiation (raising numbers to exponents) are all possible with complex numbers. Division is also possible with complex numbers, as long as the divisor is not zero. Some other calculations are also possible with complex numbers.
The rule for addition and subtraction of complex numbers is pretty simple:
Let formula_29, then formula_30, and formula_31.
Multiplication is a bit different:
formula_32
Another notable operation for complex numbers is "conjugation". A complex conjugate formula_33 to formula_15 is formula_35.
It is pretty simple, but is important for calculations, because formula_36 is actually a real number for "all" complex formula_14:
formula_38.
Because of that, we can use it to do division:
formula_39
formula_40
Other forms of describing complex numbers.
Complex numbers can be shown on a so-called complex plane. If you have a number formula_15, you can go to point "a" on the real axis and point "b" on the imaginary axis, and draw a vector from formula_42 to formula_43. The length of this vector can be calculated using the Pythagorean theorem, and the angle of this vector is simply the angle between the positive real axis and this vector—going counterclockwise. The length of a vector for a number formula_14 is called its modulus or absolute value (written as formula_45), and the angle is called its argument (formula_46).
This leads to the trigonometrical form of describing complex numbers: by the definitions of sine and cosine, it follows that for all formula_14:
formula_48
This is closely connected to De Moivre's formula.
There exists even another form, called exponential form.
Conclusion.
With the introduction of complex numbers to math, every polynomial with complex coefficients has roots in complex numbers. This introduction also helped to open a path to the creation of another kind of numbers, which could help resolve and explain many different problems. These include the , , , and many others. For more, see .
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Frederick I of Prussia
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Frederick I of Prussia (), (11 July 1657–25 February 1713) of the Hohenzollern dynasty was the first King in Prussia (1701–1713).
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Siege of Jerusalem (1187)
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The Siege of Jerusalem took place from September 20 to October 2, 1187. It was part of the war called the Third Crusade.
Balian of Ibelin defended Jerusalem against the armies of Saladin. When he surrendered, the Muslims enslaved thousands of Christians but let many leave after they bought their freedom.
A fictionalized version of the siege (attack) is seen in the movie "Kingdom of Heaven", directed by Ridley Scott.
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Beer Hall Putsch
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The Beer Hall Putsch was a failed coup d'état in Munich, Germany between the evening of 8 November and the morning of 9 November 1923.
During the Putsch, the Nazi Party under Adolf Hitler tried to take over the government of Bavaria, a state in Germany. They took several hundred people hostage in a beer hall (a large building where people got together to drink beer and sometimes listen to political speeches).
Several Nazis died when they got into a gun fight with police officers in another part of Munich. Hitler went to prison for eight months and wrote his manifesto "Mein Kampf" during that time.
Reasoning.
Hitler chose to launch the Putsch for many reasons.
At the time, Germany was the Weimar Republic. The Republic and its government were weak because of fighting between right-wing and left-wing political parties. Because of inflation, many people did not have enough money to pay daily expenses. Sometimes, wages or pensions were not paid.
The Weimar Republic's financial problems started when Germany lost World War I. Other countries made Germany pay for the entire war, and Germany had to make taxes very high in order to pay. This hurt Germany's economy.
In the early 1920s, the Nazi Party was getting very strong. Hitler was a strong leader. In 1923, the year when the Weimar Republic was least popular, the Nazi Party grew from 6,000 members to 55,000.
With the Putsch, Hitler wanted to take control of the government by force. He wanted to copy Benito Mussolini, Italy's fascist dictator, who took power by invading Rome.
Attempted coup.
On 8 November 1923, Hitler and his men entered the Beer Hall and took several hundred people hostage. The Sturmabteilung (SA) (the Nazi Party's paramilitary force) also took over the Army Headquarters, but they forgot to capture the telegraph office. This meant that anybody could call the police.
The Putsch failed. A day after it started, 16 Nazis and 4 Bavarian State Police officers were killed in a gunfight in "Residenzstraße". Hitler was arrested two days later.
Results.
After the Beer Hall Putsch, Hitler and some other participants were sent to prison for treason. Two other important Nazi Party officials, Hermann Goring and Rudolf Hess, were also imprisoned. They would later play key roles in the Holocaust.
Hitler spent about 8 months in prison, and the Nazi Party broke up after the Putsch (although it would later get back together).
The Putsch made Hitler famous. Before the Putsch, he was unknown, but afterwards many people learned about him. He was a hero to many people after the Putsch. After the governments of the Weimar Republic, many German people wanted strong leadership, and some thought Hitler would provide that.
In prison Hitler wrote "Mein Kampf" ("My Struggle"), which became one of the most famous books in history. It sold millions of copies at the time and taught many people about Hitler's ideas. Rudolf Hess helped with the book; Hitler told Hess what he wanted to say and Hess wrote it down.
After the Putsch, Hitler rethought his strategy. He realised he could not take power using violence, the way Mussolini had in Italy. Instead, he had to get power through being elected.
Causalities.
Sixteen participants in the Beer Hall Putsch died during the takeover. In "Mein Kampf", Hitler calls them martyrs: the first people ever to die for the Nazi Party. They were:
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Verona
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Verona is a city in the Veneto region of Italy with 260,000 inhabitants. It is famous for being the setting for the Shakespeare play "Romeo and Juliet" and because of the Roman Arena. This city is built on the Adige river. It has a humid subtropical climate ("Cfa" in the Köppen climate classification).
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Kyiv
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Kyiv or Kiev () is the capital and largest city in Ukraine. It is in north-central Ukraine on the Dnieper River. Over three million people live there.
It is not a part of any oblast. However, it is surrounded by Kyiv Oblast, and is the headquarters of Kyiv Oblast.
The city hosted the UEFA Euro 2012 final. Kyiv also hosted the Eurovision Song Contest in 2017.
Kyiv has a humid continental climate ("Dfb" in the Köppen climate classification).
References.
Notes
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19952
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1675412
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https://simple.wikipedia.org/wiki?curid=19952
|
Harare
|
Harare is the capital of Zimbabwe. It is home to over 1.6 million people. It was known as "Salisbury" from its foundation on September 12, 1890 until April 18, 1982.
Harare is Zimbabwe's biggest and most important financial, commercial, and communications centre, and a trade centre for tobacco, maize, cotton, and citrus fruits. Manufactured goods include textiles, steel and chemicals, and gold is mined in the area. The city's suburbs include Borrowdale, Mount Pleasant and Avondale. The richest neighbourhoods are to the north. The University of Zimbabwe, the country's oldest university (founded in 1952), is in Mount Pleasant, about 6 km (3.7 mi) north of the city centre. The country's main Test cricket ground, Harare Sports Club is in the city. The Dynamos F.C. in Harare is Zimbabwe's most successful association football team.
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19955
|
532461
|
https://simple.wikipedia.org/wiki?curid=19955
|
Seventh-day Adventist Church
|
The Seventh-day Adventist Church is a Protestant Christian group. It is different from most other Protestant groups because the followers believe that the seventh day of the week, Saturday, is the day to rest from working and worship God. The Bible calls this day the "Sabbath". The Sabbath is the seventh day of the week (Gen 2:1-3) in Judaism and in the Seventh-day Adventist Church. This is why they are called "Seventh-day Adventists." Although the abbreviation "SDA" is used, "Adventist" is the church's preferred shortening of "Seventh-day Adventist."
The Seventh-day Adventist Church came from the Millerite movement in the United States. This included people from many denominations. The Millerites started in the middle of the 19th century. They were people who followed the teachings of William Miller. Miller preached that Jesus is coming very soon, in the Second Coming or Second Advent. The church name "Adventist" came from the word "Advent." The Seventh-day Adventist Church started in 1863.
In many ways, the religious teachings of the Seventh-day Adventist church are like evangelical teachings such as the Trinity and Biblical inerrancy. Teachings that are different include the doctrine of an investigative judgment, the unconscious state of the dead (which means that when people die, they will not wake up until Christ resurrects them), and that the wicked will be destroyed forever by fire (rather than forever burn in Hell).
The church is also known for its message on health. It teaches that being healthy helps us to make good decisions, understand God’s Word, be productive in God’s service, and otherwise glorify God with our bodies as temples. Adventists who eat meat typically do not eat meat from pigs, certain fish, and other animals that the Bible names as unclean. Many Adventists are vegetarian (no meat) or vegan (no animal products, such as milk or eggs). They tend to stay away from smoking, drinking and other things known to be harmful or mind-altering. Exercise, being outdoors, resting, and drinking lots of water are other parts to healthy living usually taught by Adventists. In 2005, a National Geographic cover story identified the Adventists living in Loma Linda, California, as one of five Blue Zones of people living longer than the rest of the world.
The church also promotes religious liberty. When it comes to culture, it is more conservative.
Among the founders of the Church was Ellen G. White. She wrote a lot that is still thought to be very important in the church today. She was a dedicated Christian who believed she received visions from God about the end of the world and what heaven will be like.
At a world level, the Seventh-day Adventist Church is run by a General Conference. Smaller regions are administered by divisions, union conferences and local conferences. It is present in over 200 countries and territories and is ethnically and culturally diverse. The church runs many schools, hospitals and publishing houses worldwide, as well as a famous organization that helps people in trouble, known as the Adventist Development and Relief Agency. As of December 31, 2023, there were <mark>over 25 million</mark> Seventh-day Adventists worldwide..
Organization.
The church is organized with a representative form of church government and the world-wide Church has 13 Divisions.
The Seventh-day Adventist World Church Statistics shows the church had 15,660,347 members as of December 31, 2007.
The Adventist News Network reported in June 2010 (during the 59th quinquennial General Conference Session of the Seventh-day Adventist Church held in Atlanta, Georgia,) that Seventh-day Adventists reached a membership of 16,300,000, according to the church's Office of Archives and Statistics. The world church Secretary stated that when counting unbaptized children and family members who attend services, the church numbers between 25 and 30 million.
Mainstream doctrine.
Seventh-day Adventists believe in Protestantism.
Seventh-day Adventist believe in the 28 Fundamental Beliefs. This statement of beliefs was adopted by the General Conference in 1980, with an extra belief (number 11) being added in 2005.
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19958
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1542442
|
https://simple.wikipedia.org/wiki?curid=19958
|
Lye
|
Lye is the name of different things:
|
19960
|
1161309
|
https://simple.wikipedia.org/wiki?curid=19960
|
Luck
|
Luck can mean:
|
19961
|
640235
|
https://simple.wikipedia.org/wiki?curid=19961
|
Antony and Cleopatra
|
Antony and Cleopatra is a play by Shakespeare. It is a tragedy. Shakespeare's source was Plutarch's "Lives". The play was first performed between 1606 and 1607. It was probably first printed in the First Folio of 1623. The play describes the romantic love and suicides of Antony and Cleopatra.
|
19962
|
1142876
|
https://simple.wikipedia.org/wiki?curid=19962
|
Risorgimento
| |
19964
|
314522
|
https://simple.wikipedia.org/wiki?curid=19964
|
Het Wilhelmus
|
"Het Wilhelmus" (, ), fully known as "Wilhelmus van Nassouwe" ("William of Nassau"), is the national anthem of the Netherlands and the former national anthem of the Netherlands Antilles until 1964. Known since at least the 16th century – around the time of the Dutch Revolt – this song contains the oldest melody among all national anthems of the world. Its lyrics also date back to the 1500s, though the lyrics of "Kimigayo"—Japan's national anthem—are much older. Because "Het Wilhelmus" is so old, the origins of the composer(s) and author(s) are uncertain, but the melody has been arranged by Dutch composer Adrianus Valerius in the 1600s. It wasn't officially adopted as national anthem of the Netherlands until the 20th century.
Lyrics.
Only the first and sixth verses are sung.
Papiamento translation.
<poem>Guillen di Nassau, desendiente
Un liña hulanda i bieu,
Mi ta dedik'inmortal
Fe den e tera aki mi.
Un lider ta, imperio,
Oraño, semper liber,
Na rei di Spaña a mi duná
Un fieldat ta na bida.
Mi intento biba na
E miedu di òrdu den Dios
I por ta asina a bira un impulso,
E hendenan, e siguridat i e tera,
Ma Dios, tin, mi ta cualifica
Di produkto prepará
Bai un dia mi ta establece
Mi gobernashon.
No laga e destrukshon lo tradicional,
Mi súbditos ta bèrdadero bai bon.
Señor siguridat bo ta warda
Maske awor bo pèrsiguími.
Esun ku veira direktamente
Mester pidi Dios di dia i anochi
Pa benta di poder riba mi
Manera campeón di bo derecho.
Bida i tur e demas
Ki ora mi ta mi a sakrifiká pa bo!
I mi rumannan damanan
Demostra su devoción tambe.
Conta Dolfi, mas pober,
Kai den e Prison refleha,
Bai riba e stat semper
Ta spera di dia di Huisio Caba.
Mi, movementu nasí, baha
Di famia imparsial.
E lider di un influensha, wardami
(Destino e choque di e bataya
Diariamente i sin motibu
Manera religioso mester cristian)
Ku e sanger di mi bida e incomparable
Evangelio di Dios Nos Señor.
Un eskudo i mi konfiansa,
O Dios, bo Semper bo ta.
Konfia den bo guia.
Mi No ta laga nos no sigur.
Pa mañan tabata un religioso
Sirbidó bo pa ai
Bai sali e malesanan ku nos pone man prueba
I opreshon leu.
Mi Dios, bo ta fabor, Salbami
Di tur e pèrsiguími
I mensahe ku esclavizarme,
Bo fiel sirbidó.
Tata, mi no sances
Di nada i kubrí diseño,
No laga ku ta laba man
Sanger ta inosente di mi.
O David, buscaste refugio
Di opreshon di Rei Saul.
Asta asina huí di e alte
I hopi Señor mi.
Ma Señor Dios a salba
Di exilio i su fièrnu
I, den Su kariño, a dun'é
Un reino di Israel.
No logra sin fin
E nubianan ta estadia na spears.
Ta spera ku e ta masha agradabel
Mi kurason prinsipio,
Bo ta ku mi ku honor
Topa ku e morto di e guera,
Bai partisipá den e shelu mi donate,
Di fiel uzá.
Nada move mi kompashon
Manera ta wak kla di e terenonan,
Kunuku, pueblo, pueblo i stat
Destruí na man fugitivo.
Òf ku e español lo vele,
Mi Hulanda asina dushi,
E idea pa mi are
Hasiendo mi kurason sanger.
Un nada di koral di Humor
Mi ta spera ku mi anfitrion
E yama e tirano e bataya,
Bo no ta trei di prisoner.
Pa, banda di March instala,
Temor e forsa ku mi ejercía.
Mi koredó mira un rbtt
Resientemente na e otro banda di tereno.
Si Al a deseá i,
Ora supla e faro tormento,
Mi ta lo calmado,
Òf ta bolbe su explosión di bo
Esun ku ta biba den e shelu,
Unda konsoladó tur nos bendishon,
Pa e motibu aki a duna di gradisimentu ai,
No tabatin asina.
Sigur mi kurason ta permanesé
Mi prosperidat
Mi balor prinsipio ta pensa
Tur e spir pa biba i ta.
Mi pasado e Señor mi skol
Ku un kurason ferviente i tenso
Pa salbami di desaster
I prueba mi inosensia.
Ai mi ta. Pa kòrta
Ta duru pa nos. Riba e bista.
Bo wardadó lanta, unda bo ta deseá
Plamá por biba,
Pidi Dios ku lo alivia.
Di evangelio ta bo cura.
Kana den e pasonan di Jesu
E bida aki no ta uno.
Señor nan poder
Mi ta rekonosé.
Mi no tin ningun or
Malu di Rei a papia.
Sinembargo, den Dios, esun di mas grandi
Di Mahestad ku mester
Obedensia promé i último,
Pasobra e hustisia asina ta nifiká.</poem>
IPA transcription.
<poem>[ʋɪɫ.ˈɦɛɫ.mʏs vɑn nɑ.ˈsɑu̯.ø]
[bɛn ɪk vɑn ˈdœy̯t.sən blut]
[dɛn ˈvaː.dør.ˌɫɑnt ɣø.ˈtrɑu̯.ø]
[blɛi̯v ɪk tɔt ɪn dɛn doː(w)t]
[ən ˈprɪn.sø vɑn ˌoː(w).ˈrɑn.jø]
[bɛn ɪk frɛi̯ ˌɔn.vør.ˈveːrt]
[dɛn ˈkoː(w).nɪŋ vɑn ɦɪs.ˈspɑn.jø]
[ɦɛp ɪk ˈɑɫ.tɛi̯t ɣø.ˈeːrt]
[mɛi̯n sxɪɫt ˈɛn.dø bø.ˈtrɑu̯.ən]
[ˈzɛi̯t ɣɛi̯ oː(w) ɣɔt mɛi̯n ɦeːr]
[ɔp y zoː(w) ʋɪl ɪk ˈbɑu̯.ən]
[vər.ˈlaːt mɛi̯ ˌnɪ.mør.ˈmeːr]
[dɑt ɪk dɔx froː(w)m mɑɣ ˈblɛi̯.vən]
[yu̯ ˈdi.naːr ˈtɑ.lør stɔnt]
[dø ˌti.rɑ.ˈni vər.ˈdrɛi̯.vən]
[di mɛi̯ mɛi̯n ɦɑrt ˈdoːr.ʋɔnt]</poem>
|
19968
|
10249765
|
https://simple.wikipedia.org/wiki?curid=19968
|
1803
|
1803 (MDCCCIII) was a common year starting on Saturday in the Gregorian calendar and a common year starting on Thursday in the Julian calendar.
|
19969
|
10249929
|
https://simple.wikipedia.org/wiki?curid=19969
|
1661
| |
19970
|
10389598
|
https://simple.wikipedia.org/wiki?curid=19970
|
1579
|
1579 (MDLXXIX) was a common year starting on Thursday in the Julian calendar.
|
19971
|
10249398
|
https://simple.wikipedia.org/wiki?curid=19971
|
752
| |
19972
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19972
|
1005
| |
19973
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19973
|
1233
| |
19974
|
10350791
|
https://simple.wikipedia.org/wiki?curid=19974
|
1736
|
1736 (MDCCXXXVI) was a leap year starting on Sunday in the Gregorian calendar and a leap year starting on Thursday in the Julian calendar.
|
19975
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19975
|
1340
| |
19976
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19976
|
1128
| |
19977
|
10249482
|
https://simple.wikipedia.org/wiki?curid=19977
|
984
| |
19978
|
10249953
|
https://simple.wikipedia.org/wiki?curid=19978
|
1639
| |
19979
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19979
|
1003
| |
19980
|
196884
|
https://simple.wikipedia.org/wiki?curid=19980
|
Fuzzy logic
|
Fuzzy logic is a sort of computer logic that is different from boolean algebra founded by Lotfi A. Zadeh. It is different in the way that it allows values to be more accurate than on or off. While boolean logic only allows true or false, fuzzy logic allows all things in between. An example of this could be a computer game: A person is standing in a doorway while a thing explodes. The character is hit or not hit if boolean logic is used, but the doorway protects him from the explosion. Therefore, he might only be hit 20%, and takes less damage.
To put it in more precise mathematical terms, classical logic has two values. These values are usually called "false" (0) or "true" (1). With fuzzy logic, a (calculated) value of 0.8 or 0.971 is possible. It is important to know the difference between fuzzy logic and chance. A coin that is thrown has a chance of 0.5 for landing heads up. If it is thrown 1000 times, it is expected that it will land with heads side up 500 times. With fuzzy logic, a thing with a "truth value" of 0.5 will have a value of 0.5 no matter how many times it is done. It is not a 50% chance of true or untrue, it is 50% true and 50% untrue at the same time.
Fuzzy logic is used a lot in expert systems and neural networks.
Humans tend to use a combination of predicate logic and fuzzy logic. If you are an outfielder catching a baseball hit into the air, then your precise logic will calculate trajectory and start you running to the point of intercept (catching). However, once close to the ball the eyes and brain of the outfielder lacks the ability to accurately estimate distance and speed because the ball is coming straight at the outfielder. The human brain switches to fuzzy logic that says "get me closer", "get me closer", and so on. That is why you see outfielders in baseball run to a spot and then move around as the ball gets closer.
Predicate logic says calculate the point to be at to catch the ball. Fuzzy logic says because of wind or other things you might not be in the correct place so just keep getting closer until you catch the ball.
In predicate logic it is the mathematics of calculating the path of the ball that determines your action. In fuzzy logic it is the error of your calculations that determines your action.
In effect, it's like your brain trying to steady a drink in your hand while traveling down a bumpy road.
|
19981
|
22027
|
https://simple.wikipedia.org/wiki?curid=19981
|
Douala
|
Douala is the largest city in the African country of Cameroon. It is the capital city of Littoral Region.
The city is placed near the Wouri River. Its population is about 2,000,000 people. The first European people who came to Douala were from Portugal. They found Duala in about 1472. Before 1884 it was named Cameroons Town. In 1884 German people came to Duala and changed its name to Kamarunstadt ("Camaroon City") and made it the capital of German Kamerun. In 1907 its name was changed to Duala. It became the capital of French Cameroons in 1919. From 1940 to 1946, it was the capital of Cameroon.
Duala is an expensive city. It ranked 24th most expensive city of the world in 2007.
Transport.
Douala is linked by rail to Yaoundé, Ngaoundéré, Kumba and Nkongsamba. The largest port and the most important airport in Cameron are both in Douala.
|
19982
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19982
|
1843
|
Events.
January 29 - William McKinley, twenty-fifth President of the United States (d. 1901)
|
19983
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19983
|
1225
| |
19987
|
10249409
|
https://simple.wikipedia.org/wiki?curid=19987
|
841
| |
19988
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19988
|
1164
| |
19989
|
10249370
|
https://simple.wikipedia.org/wiki?curid=19989
|
578
| |
19990
|
793
|
https://simple.wikipedia.org/wiki?curid=19990
|
The Mothers of Invention
| |
19991
|
16529
|
https://simple.wikipedia.org/wiki?curid=19991
|
Traditional
| |
19992
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19992
|
1707
| |
19993
|
10249465
|
https://simple.wikipedia.org/wiki?curid=19993
|
972
| |
19994
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19994
|
1031
| |
19995
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19995
|
1083
| |
19996
|
1011873
|
https://simple.wikipedia.org/wiki?curid=19996
|
1027
|
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