ejaasaari/simplewiki-2025-04-01 huggingface dataset:
The transition metals are a group of metals that are found in the middle of the periodic table. The alkaline earth metals, beginning with beryllium are to the left and the boron group elements are to the right. The term "transition element" was invented for them in 1921. The atomic numbers of these metals are from 21 to 30, 39-48, 57, 72-80, 89 and 104-112. Many elements like Zn, Cd, Hg, La and Ac have a highly debatable position in the transition series of elements. La and Ac are also classed in the lanthanide series and actinide series respectively. Transition metals have several general properties. They are harder and less reactive than the alkaline earth metals. They are also harder than the post transition metals. They make colorful chemical compounds with other elements. Most of them have more than one oxidation state. Like other metals, they are electrical conductors. Some of the transition metals are necessary to keep humans healthy, such as iron, zinc, and chromium. Other elements in the transition metals can be harmful to our body, like cadmium and mercury. Other elements like gold or silver do not harm or help us. There are more transition metals than any other groups in the periodic table. Only a few of the transition metals are colored; most of them are silver-gray or silver-bluish.
Osmium is a chemical element. It is element number 76 on the periodic table. Its symbol is "Os". There is not much osmium on earth. There is actually such a small amount that osmium is very expensive. Osmium is a metal and it does not react very much, and such a metal is known as a "noble metal". Osmium is the densest (heaviest for the same amount) element on the periodic table. It was discovered in 1804 by Smithson Tennant in London, England. He found it together with Iridium in a bit of Platinum, which he had dissolved in Aqua regia. Characteristics. Osmium has a blue-grey hue and is the densest stable element; it is about twice as dense as lead and slightly denser than iridium. Osmium is a hard but brittle metal that stays shiny even at high temperatures. It has a very low squeezability. Accordingly, its size module is extremely high, reported between 395 and 462 GPa, which is comparable to that of diamond (443 GPa). The hardness of osmium is moderately high at 4 GPa. Because of its hardness, brittleness, low vapour pressure, and very high melting point, solid osmium is difficult to machine, form, or work.
"Radon" is a chemical element in the periodic table. It is element 86 on the periodic table and its symbol is Rn. It is an odorless, tasteless noble gas. It is quite radioactive and can decay very quickly. 27 isotopes of Radon are known today. The most stable of them has a half life of about 3.8 days.  Chemistry. Radon is a gas and is part of the group known as the noble gases. It does not react with other elements, so it is found pure. Radon is radioactive, meaning that it can give off harmful rays. Some people have high levels of radon in their houses, and this can be very dangerous. A lot of radon can get stuck in the basement of old houses, and so people end up breathing it in. It gets stuck in the lungs and has been known to cause cancer. There are groups that try to make sure there is no dangerous radon in houses. It can occur naturally on the Earth but is a very small amount. As elements like Thorium and Uranium decay, some of that gets turned into Radon. Radon can cause lung cancer and is the second most popular cause of lung cancer straight after smoking. History. Radon was the fifth radioactive element to be discovered, in 1899 by Ernest Rutherford and Robert B. Owens at McGill University in Montreal, after uranium, thorium, radium, and polonium. In 1899, Pierre and Marie Curie saw that the gas given off by radium remained radioactive for a month. Later that year, Rutherford and Owens noticed different types of them when trying to measure radiation from thorium oxide. Uses. It is sometimes used in radiation therapy. However, it is very dangerous to use.
FTP, also known as File Transfer Protocol, is a communication protocol for the rapid, simple transmission of files across a network supporting the TCP/IP. This network is generally the Internet, or a local network. FTP is a way of accessing files on another computer. FTP uses the Client-Server architecture, meaning that there is a server, that holds the files, and does the authentication, and a client, or the end-user, who is accessing the files. The server listens on the network for connection requests from other computers. The client can make a connection to the FTP server by using FTP client software. Once connected and authenticated (via rsh or SFTP) the client can do things such as uploading files to the server, downloading files (taking the server's files and putting them on his own computer) from the server, and renaming, deleting files on the server, changing file permissions, etc. Most modern operating systems support FTP. This implies that any computer connected to a TCP/IP based network can manipulate files on another computer on that network regardless of which operating systems are involved, provided that they are open to FTP connections. There are many existing FTP client and server programs, many of these are available free, or open source. FTP connection is also seen in cellular phones when trying to transfer or receive data from a computer nearby. FTP return codes. FTP server return codes show their status by the digits within them. A short explanation of various digits' meanings are given below: FTP modes. FTP may run in "active" or "passive" mode, which determines how the data connection is established. In both cases, the client creates a TCP control connection from a random, usually an unprivileged, port N to the FTP server command port 21. FTP Servers. Some popular open source FTP server implementations are:
Hypertext Transfer Protocol (usually abbreviated to HTTP) is a communications protocol. It is used to send and receive webpages and files on the internet. It was developed by Tim Berners-Lee and is now coordinated by the W3C. HTTP/1.1 is the most-used version today, and RFC 2616 completely explains how it should work. As of April 2023, about 39% of websites already use the next version, HTTP/2 (which works in nearly all web browsers), and over 27% of websites already work with the newest version, HTTP/3, which came out in 2022. HTTP/3 is faster for most webpages in the real world. It is faster than both HTTP/2 and HTTP/1.1, sometimes more than three times as fast as HTTP/1.1. HTTPS. The secure variant of HTTP is called HTTPS (Hypertext Transfer Protocol Secure), and is used by more than 79% of websites, such as payment websites (if it's not used, then it's a clear signal that the payment site is a scam). HTTPS is used by default by most web browsers (even if not requested by the user), assuming the web server supports it. If browsing to a website, and the web browser shows it starting with codice_1 without an codice_2 before the colon (or an unlocked icon is seen), then that website is not secure, then passwords or other data sent to them can be stolen. HTTPS encrypts all the information that is both sent and received. This can, therefore, stop malicious users such as hackers from stealing the information. HTTPS uses port 443 for communication instead of port 80. HTTP works as such, a user agent, usually meaning the web browser, connects to a (web) server. A user agent could also be a web crawler, or so-called "spider", but most users do not use such tools (they are used by search engines, such as Google). The server must be located using a URL or URI. It normally connects to port 80 on a computer. Request message. The request message (for HTTP/1.1 and older)
Ethernet is a way of connecting computers together in a local area network or LAN. It has been the most widely used method of linking computers together in LANs since the 1990s. The basic idea of its design is that multiple computers have access to it and can send data at any time. This is comparatively easy to engineer.  If two computers send data at the same time, a collision will occur. When this happens, the data sent is not usable. In general, both computers will stop sending, and wait a random amount of time, before they try again. A special protocol was developed to deal with such problems. It is called Carrier sense multiple access with collision detection or CSMA/CD. Different cable types. There are different Ethernet standards. Today, Ethernet cables look like thick telephone cables. They connect to boxes called hubs or switches. Each cable runs from a computer's network interface card (NIC) to such a box. This cable is called 10BaseT or 100BaseT, or 1000BaseT Cable. All cable types: Today, the cables for 10BaseT, 100BaseT, and 1000BaseT are the same. Their transmission medium is unshielded twisted pair for Category 5 (UTP-Cat5) or 5e. Shielded cable (STP-Cat5 or Cat5e) can be used when there is a lot of electrical noise, and Category 6 (UTP-Cat6 or STP-Cat6) works better with faster signals such as 1GBit or 10GBit. Different devices. Other devices, such as video game consoles, can also be connected using the same kind of cabling. Certain computer peripherals, for example printers and certain hard disks can be directly connected to the network with such cables. Different speeds. Ethernet can go at different speeds. In the beginning, Ethernet was at 10 MBits per second. The Ethernet most often used today is at 100 MBits per second. Most new computers now have the NIC built in, and can go at 1GBit per second. There are also standards for 1GBit per second and 10 GBit per second. 100 MBit can usually talk to 10 MBit, and 1 GBit can talk to 100 MBit and usually to 10 MBit (both full and half duplex).
Obesity is the condition of being much too heavy for one's height so that one's health is affected. In other words, it means to be too overweight. Also known as being fat. It is considered a disease and has been described as an epidemic and a form of suicide. To know if a person is overweight, the body mass index (BMI) is calculated, by dividing the person's weight (in kilograms), by their height (in metres) squared (multiplied by itself). (This is only meaningful for adults who are fully grown, and should not be used for children. Growth charts can be used to measure obesity in children.) A BMI between 18.5 and 25 is considered "normal". People with a BMI of 25 or more are said to be overweight; with 30 and above, they are considered obese, and with 35 and above, they are considered "severely obese" (this used to be called "morbidly obese"). In general, the BMI number is a good quantifiable measurement of a person's obesity. However, it is a poor predictor in people who are very athletic, because a person with a higher than average amount of muscle tissue will weigh more than an average person, thus resulting in a BMI that is higher than normal, even if that person is very large. In 2024 a study of more than 220 million people in almost 200 countries, found that more than 1 billion people were obese. Between 1990 and 2022 obesity in women increased from 8.8% to 18.5% and for men from 4.8% to 14%. Causes. The most common cause for obesity is eating more calories than are used by the body. Other factors that often contribute to obesity are: Genetics are known to contribute to obesity. Low levels of leptin, a hormone, is linked to obesity. Health issues. Many health problems are associated with obesity. An example is Type 2 diabetes. A woman with a BMI higher than 35 is 93 times more likely to develop diabetes. A 2009 review found that people with a BMI between 40 and 50 were 22.5 times
Phillips Academy (also called Andover, Phillips Andover, or PA) is a high school for boys and girls in Andover, Massachusetts, near Boston, USA. The school is a boarding school. 75% of the students live there. Phillips Academy is one of the oldest private boarding schools in the United States. Two American Presidents, George H. W. Bush and George W. Bush, went to school there. Phillips Academy was founded during the American Revolution as an all-boys school in 1778. The great seal of the school was designed by Paul Revere. George Washington's nephews went to the school, and he once spoke at an assembly while visiting. John Hancock, the famous signer of the United States Declaration of Independence, signed the articles of incorporation. Phillips Exeter Academy was made three years later in Exeter, New Hampshire by Samuel Phillips' uncle John. The football teams have played against each other almost every year since 1878. This makes their rilvalry one of the oldest high school rivalries in the country. Paul Revere put bees, a beehive, and the sun into the school's great seal. The school's main motto, "Finis Origine Pendet", means "the end depends upon the beginning." It is written at the bottom of the seal. The school's second motto, "Non Sibi" means "not for self."
Gluttony is a wasting of resources. Usually it is food that is wasted. Either one person eats too much, or the person does something so the food (or the resources) do not reach those who need it. In Christianity, this is considered to be one of the Seven deadly sins.
"Mazurek Dąbrowskiego" (, meaning "Dąbrowski's Mazurka") is the national anthem of Poland. It is commonly called "Poland is Not Yet Lost" in English. The words of the song were written in 1797 by a Polish nobleman named Józef Wybicki. Kazimierz Sikorski rearranged the song's music, though the original composer is not known. It was officially adopted as the country's national anthem in 1927.
Profit is how much money somebody (normally a company) makes. This is found by subtracting how much money they have spent ("expenditure") from how much money they have brought in (revenue). An example. If John spends $15 on some ice cream cones, and then sells them for $20, he has made a profit of $5. This is because he made $20 but when the $15 he used to buy the ice cream cones is subtracted, what is left is $5. In the end, he has $5 more than he had before he bought and sold the ice cream cones.
Roasting is a way of cooking. Something gets roasted if it is put over a fire, and some is burnt. The same effect can also be attained with a grill at a barbecue. Meat. In different countries people like to roast different things. People usually roast meats such as pork, beef, chicken, lamb, and duck. The roasted meat, along with its accompanying vegetables, is often called a roast. Most meat being roasted has to cook for a relatively long time, to ensure that it is cooked through. Variations to this include lamb and beef, which may be left "pink" or partially uncooked towards the centre. Other. Other things can be roasted too. For example, vegetables, coffee and chocolate. Coffee and chocolate are always roasted.
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.
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:
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), chloroplast
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.
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