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Islam and cats - Video Learning - WizScience.com
 
02:37
The domestic cat is a revered animal in Islam. Admired for its cleanliness as well as for being loved by the prophet Muhammad, the cat is considered "the quintessential pet" by Muslims. Cats have been venerated in the Near East since antiquity, a tradition adopted by Islam, albeit in a much modified form. Muhammad is reported to have said that "a love of cats is an aspect of faith"; according to other hadiths, he prohibited the persecution and killing of cats. The prophet purportedly allowed a cat to give birth on his cloak, and cut off the sleeve of his prayer robe rather than wake his favourite cat, a female named Muezza, who was sleeping on it. One of Muhammad's companions was known as Abu Hurairah for his attachment to cats. Abu Hurairah claimed that he had heard the Prophet declare that a woman went to Hell for starving a female kitten and not providing her with any water, but this was disputed by the Prophet's widow Aisha. According to legend, Abu Hurairah's cat saved Muhammad from a snake. The grateful prophet stroked the cat's back and forehead, thus blessing all cats with the righting reflex. The stripes some cats have on their foreheads are believed to mark the touch of Muhammad's fingers. The American poet and travel author Bayard Taylor was astonished when he discovered a Syrian hospital where cats roamed freely. The institution, in which domestic felines were sheltered and nourished, was funded by a waqf, along with caretakers' wages, veterinary care and cat food. Edward William Lane , British Orientalist who resided in Cairo, described a cat garden originally endowed by the 13th-century Egyptian sultan Baibars, whose European contemporaries held a very different attitude towards cats, eating them or killing them under papal decrees. Aside from protecting granaries and food stores from pests, cats were valued by the paper-based Arab-Islamicate cultures for preying on mice that destroyed books. For that reason, cats are often depicted in paintings alongside Islamic scholars and bibliophiles. The medieval Egyptian zoologist Al-Damiri wrote that the first cat was created when God caused a lion to sneeze, after animals on Noah's Ark complained of mice. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Islam+and+cats, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Plasma actuator - Video Learning - WizScience.com
 
02:15
"Plasma actuators" are a type of actuator currently being developed for aerodynamic flow control. Plasma actuators impart force in a similar way to ionocraft. The working of these actuators is based on the formation of a low-temperature plasma between a pair of asymmetric electrodes by application of a high-voltage AC signal across the electrodes. Consequently, air molecules from the air surrounding the electrodes are ionized, and are accelerated through the electric field. Plasma actuators operating at the atmospheric conditions are promising for flow control, mainly for their physical properties, such as the induced body force by a strong electric field and the generation of heat during an electric arc, and the simplicity of their constructions and placements. In particular, the recent invention of glow discharge plasma actuators by Roth that can produce sufficient quantities of glow discharge plasma in the atmosphere pressure air helps to yield an increase in flow control performance. Either a direct current or an alternating current power supply or a microwave microdischarge can be used for different configurations of plasma actuators. One schematic of an AC power supply design for a dielectric barrier discharge plasma actuator is given here as an example. The performance of plasma actuators is determined by dielectric materials and power inputs, later is limited by the qualities of MOSFET or IGBT. The driving waveforms can be optimized to achieve a better actuation . However, a sinusoidal waveform may be more preferable for the simplicity in power supply construction. The additional benefit is the relatively less electromagnetic interference. Pulse width modulation can be adopted to instantaneously adjust the strength of actuation. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Plasma+actuator, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Plasma+actuator, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Ceramic materials - Video Learning - WizScience.com
 
02:31
"Ceramic materials" are inorganic, non-metallic materials made from compounds of a metal and a non metal. Ceramic materials may be crystalline or partly crystalline. They are formed by the action of heat and subsequent cooling. Clay was one of the earliest materials used to produce ceramics, as pottery, but many different ceramic materials are now used in domestic, industrial and building products. Ceramic materials tend to be strong, stiff, brittle, chemically inert, and non-conductors of heat and electricity, but their properties vary widely. For example, porcelain is widely used to make electrical insulators, but some ceramic compounds are superconductors. A ceramic material may be defined as any inorganic crystalline material, compounded of a metal and a non-metal. It is solid and inert. Ceramic materials are brittle, hard, strong in compression, weak in shearing and tension. They withstand chemical erosion that occurs in an acidic or caustic environment. In many cases withstanding erosion from the acid and bases applied to it. Ceramics generally can withstand very high temperatures such as temperatures that range from 1,000 °C to 1,600 °C . Exceptions include inorganic materials that do not have oxygen such as silicon carbide. Glass by definition is not a ceramic because it is an amorphous solid . However, glass involves several steps of the ceramic process and its mechanical properties behave similarly to ceramic materials. Traditional ceramic raw materials include clay minerals such as kaolinite, more recent materials include aluminium oxide, more commonly known as alumina. The modern ceramic materials, which are classified as advanced ceramics, include silicon carbide and tungsten carbide. Both are valued for their abrasion resistance, and hence find use in corrosive environments such as the wear plates of crushing equipment in mining operations where other ceramic materials would not be suitable. Advanced ceramics are also used in the medicine, electrical, and aerospace industries. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Ceramic+materials, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Bismuth - Video Learning - WizScience.com
 
02:15
"Bismuth" is a chemical element with symbol "Bi" and atomic number 83. Bismuth, a pentavalent post-transition metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally, although its sulfide and oxide form important commercial ores. The free element is 86% as dense as lead. It is a brittle metal with a silvery white color when freshly produced, but is often seen in air with a pink tinge owing to surface oxidation. Bismuth is the most naturally diamagnetic element, and has one of the lowest values of thermal conductivity among metals. Bismuth metal has been known since ancient times, although until the 18th century it was often confused with lead and tin, which share some physical properties. The etymology is uncertain, but possibly comes from Arabic "bi ismid", meaning having the properties of antimony or German words "weisse masse" or "wismuth" , translated in the mid-sixteenth century to New Latin "bisemutum". Bismuth has long been considered as the element with the highest atomic mass that is stable. However, in 2003 it was discovered to be weakly radioactive: its only primordial isotope, bismuth-209, decays via alpha decay with a half life more than a billion times the estimated age of the universe. Bismuth compounds account for about half the production of bismuth. They are used in cosmetics, pigments, and a few pharmaceuticals, notably Pepto-Bismol, used to treat diarrhea. Bismuth's unusual propensity to expand upon freezing is responsible for some of its uses, such as in casting of printing type. Bismuth has unusually low toxicity for a heavy metal. As the toxicity of lead has become more apparent in recent years, there is an increasing use of bismuth alloys as a replacement for lead. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Bismuth, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Bismuth, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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mammals of West Virginia - Video Learning - WizScience.com
 
02:26
The state of West Virginia is home to 72 wild mammal species. Four – the Virginia big-eared bat, the Indiana bat, the West Virginia northern flying squirrel and the newly extinct eastern cougar – are federally listed as endangered. Several additional species are rare in the state and warrant close monitoring. Some mammals which have thrived despite human disturbance include the opossum, which is more abundant and more widely distributed due to human activities. Also doing well are mammals that prefer farm and early successional habitats. The coyote is expanding its range eastward in the United States and now occurs throughout the state. Many examples of West Virginia's present and former megafauna are on display at the West Virginia State Wildlife Center, a small zoo featuring native animals. The following letters indicate the likelihood of finding each animal in West Virginia: "Family Didelphidae " "Family Soricidae " "Family Talpidae " "Family Vespertilionidae " "Family Sciuridae " "Family Castoridae " "Family Dipodidae " "Family Cricetidae " "Family Muridae " "Family Erethizontidae " "Family Leporidae " "Family Canidae " "Family Ursidae " "Family Procyonidae " "Family Mustelidae " "Family Mephitidae " "Family Felidae " "Family Suidae " "Family Cervidae " "Family Bovidae " During colonial times, the black rat , Norway rat and house mouse all came to North America, including the future West Virginia, with European settlers and traders. Dogs, cats, pigs and goats that have wandered off or were abandoned have established or feral populations in portions of the state. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/List+of+mammals+of+West+Virginia, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Composition of Mars - Video Learning - WizScience.com
 
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The "composition of Mars" covers the branch of the geology of Mars that describes the make-up of the planet Mars. Mars is a terrestrial planet, which means that its bulk composition, like Earth's, consists of silicates , metals, and other elements that typically make up rock. Also like Earth, Mars is a differentiated planet, meaning that it has a central core made up of metallic iron and nickel surrounded by a less dense, silicate mantle and crust. The planet's distinctive red colour is due to the oxidation of iron on its surface. Much of what we know about the elemental composition of Mars comes from orbiting spacecraft and landers. Most of these spacecraft carry spectrometers and other instruments to measure the surface composition of Mars by either remote sensing from orbit or "in situ" analyses on the surface. We also have many actual samples of Mars in the form of meteorites that have made their way to Earth. Martian meteorites provide data on the chemical composition of Mars' crust and interior that would not otherwise be available except through a sample return mission. Based on these data sources, scientists think that the most abundant chemical elements in the martian crust, besides silicon and oxygen, are iron, magnesium, aluminum, calcium, and potassium. These elements are major components of the minerals comprising igneous rocks. The elements titanium, chromium, manganese, sulfur, phosphorus, sodium, and chlorine are less abundant but are still important components of many accessory minerals in rocks and of secondary minerals in the dust and soils . Hydrogen is present as water ice and in hydrated minerals. Carbon occurs as carbon dioxide in the atmosphere and sometimes as dry ice at the poles. An unknown amount of carbon is also stored in carbonates. Molecular nitrogen makes up 2.7 percent of the atmosphere. As far as we know, organic compounds are absent except for a trace of methane detected in the atmosphere. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Composition+of+Mars, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Ornate box turtle - Video Learning - WizScience.com
 
02:25
The "ornate box turtle" is one of only two terrestrial species of turtles native to the Great Plains of the United States. It is one of the two different subspecies of "Terrapene ornata". It is the state reptile of Kansas. It is a relatively small turtle, that is currently listed as threatened in Illinois but is of concern and protected in six Midwestern states . Males and females generally look alike but males are often smaller; there is color variation with yellow lines from the center of the shell to the edges through gray, red-brown, or black coloration. Besides the size, males can be distinguished from females in several ways; a large curved inner claw on the back feet, a cloacal opening that is farther back in males, a longer and thicker tail, and reddish color on the legs and occasionally on the jaw. The home range of the ornate box turtle covers a large area of the Midwest, from Wisconsin to the Gulf of Mexico and from Louisiana to Colorado. It was first discovered in Nebraska in 1795, where "vast numbers" were found. The turtle is usually found in grasslands and on land rather than in water; they have been found in all habitat types of the Great Plains except aquatic, though most references indicate they prefer open grass or prairie lands. Several studies indicate that the ornate box turtle needs three specific types of microhabitats in order to survive: # grass areas for feeding that have some free water # areas where females can nest and burrow into the soil to overwinter # sites for resting and thermoregulation where turtles can bury themselves in soil to protect themselves from extreme temperatures and to avoid dehydration in summer and eat their own eggs Water is important for this turtle to regulate body temperature in hot weather and to replace body water after hibernation, but they do not spend large amounts of time in flowing or standing water. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Ornate+box+turtle, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Albertosaurus - Video Learning - WizScience.com
 
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""Albertosaurus"" is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, about 70 million years ago. The type species, "A. sarcophagus", was apparently restricted in range to the modern-day Canadian province of Alberta, after which the genus is named. Scientists disagree on the content of the genus, with some recognizing "Gorgosaurus libratus" as a second species. As a tyrannosaurid, "Albertosaurus" was a bipedal predator with tiny, two-fingered hands and a massive head that had dozens of large, sharp teeth. It may have been at the top of the food chain in its local ecosystem. Although relatively large for a theropod, "Albertosaurus" was much smaller than its more famous relative "Tyrannosaurus", probably weighing less than 2 metric tons. Since the first discovery in 1884, fossils of more than 30 individuals have been recovered, providing scientists with a more detailed knowledge of "Albertosaurus" anatomy than is available for most other tyrannosaurids. The discovery of 26 individuals at one site provides evidence of pack behaviour and allows studies of ontogeny and population biology, which are impossible with lesser-known dinosaurs. "Albertosaurus" was smaller than some other tyrannosaurids, such as "Tarbosaurus" and "Tyrannosaurus". Typical "Albertosaurus" adults measured up to 9 m long, while rare individuals of great age could grow to be over 10 m long. Several independent mass estimates, obtained by different methods, suggest that an adult "Albertosaurus" weighed between 1.3 tonnes and 1.7 tonnes . Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Albertosaurus, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Geomorphology - Video Learning - WizScience.com
 
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"Geomorphology" is the scientific study of the origin and evolution of topographic and bathymetric features created by physical or chemical processes operating at or near the earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphology is practiced within physical geography, geology, geodesy, engineering geology, archaeology and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field. The surface of the earth is modified by a combination of surface processes that sculpt landscapes, and geologic processes that cause tectonic uplift and subsidence, and shape the coastal geography. Surface processes comprise the action of water, wind, ice, fire, and living things on the surface of the earth, along with chemical reactions that form soils and alter material properties, the stability and rate of change of topography under the force of gravity, and other factors, such as human alteration of the landscape. Many of these factors are strongly mediated by climate. Geologic processes include the uplift of mountain ranges, the growth of volcanoes, isostatic changes in land surface elevation , and the formation of deep sedimentary basins where the surface of the earth drops and is filled with material eroded from other parts of the landscape. The earth surface and its topography therefore are an intersection of climatic, hydrologic, and biologic action with geologic processes, or alternatively stated, the intersection of the earth's lithosphere with its hydrosphere, atmosphere, and biosphere. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Geomorphology, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Randall cattle - Video Learning - WizScience.com
 
02:09
"Randall cattle" are a rare breed of cattle that originated in Sunderland, Vermont. Randall cattle are a rare breed of purebred cattle developed in Sunderland, Vermont, USA, on the farm of Samuel Randall, and later his son, Everett Randall. The Randall family kept a closed herd for over 80 years. Randalls are considered to be a landrace breed, descended from the local cattle common in New England in the nineteenth Century. In 1985 the Randall cattle were rescued from the Randall farm after Everett Randall had died. The animals were widely dispersed but soon began to disappear. Cynthia Creech, then living in Tennessee, stepped in to purchase most of the remaining animals to preserve the genetics from extinction. During the following years the breed was called various names but in the 1990s it was decided that they would be called Randall cattle and the Registry was set up with that name in 2001. Randalls have historically been used as a dairy breed, although they also possess meat and draft qualities. From fewer than 20 animals the breed population has increased to over 250 breeding females. Randall cattle are quite variable in size and conformation and have a constitution that is suited to the New England climate. Randalls on average are medium in size with the cows weighing about 600-1100 lbs. and bulls weighing from 1000 to 1800 lbs. or more. Randall cattle have a "Colour-sided" lineback pattern, black markings on a white base, varying from almost white to very dark. Other subtle shades such as blue, mahogany, and gray have been observed, and there are now a number of recessive reds. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Randall+cattle, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Abdomen - Video Learning - WizScience.com
 
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"Abdomen" constitutes the part of the body between the thorax and pelvis: in humans and in other vertebrates such as mammals. The region enclosed by the abdomen is termed the abdominal cavity. In arthropods it is the posterior tagma of the body; it follows the thorax or cephalothorax. Anatomically, the abdomen stretches from the thorax at the thoracic diaphragm to the pelvis at the pelvic brim. The pelvic brim stretches from the lumbosacral angle to the pubic symphysis and is the edge of the pelvic inlet. The space above this inlet and under the thoracic diaphragm is termed the abdominal cavity. The boundary of the abdominal cavity is the abdominal wall in the front and the peritoneal surface at the rear. The abdomen contains most of the tubelike organs of the digestive tract, as well as several solid organs. Hollow abdominal organs include the stomach, the small intestine, and the colon with its attached appendix. Organs such as the liver, its attached gallbladder, and the pancreas function in close association with the digestive tract and communicate with it via ducts. The spleen, kidneys, and adrenal glands also lie within the abdomen, along with many blood vessels including the aorta and inferior vena cava. Anatomists may consider the urinary bladder, uterus, fallopian tubes, and ovaries as either abdominal organs or as pelvic organs. Finally, the abdomen contains an extensive membrane called the peritoneum. A fold of peritoneum may completely cover certain organs, whereas it may cover only one side of organs that usually lie closer to the abdominal wall. Anatomists call the latter type of organs "retroperitoneal." Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Abdomen, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Early world maps - Video Learning - WizScience.com
 
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The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BC still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period. The developments of Greek geography during this time, notably by Eratosthenes and Posidonius culminated in the Roman era, with Ptolemy's world map , which would remain authoritative throughout the Middle Ages. Since Ptolemy, knowledge of the approximate size of the globe allowed cartographers to estimate the extent of their geographical knowledge, and to indicate parts of the globe known to exist but not yet explored as "terra incognita". With the Age of Discovery, during the 15th to 18th centuries, world maps became increasingly accurate; exploration of Antarctica and the interior of Africa was left to the 19th and early 20th century. A Babylonian world map, known as the "Imago Mundi", is commonly dated to the 6th century BCE. The map as reconstructed by Eckhard Unger shows Babylon on the Euphrates, surrounded by a circular landmass showing Assyria, Urartu and several cities, in turn surrounded by a "bitter river" , with seven islands arranged around it so as to form a seven-pointed star. The accompanying text mentions seven outer regions beyond the encircling ocean. The descriptions of five of them have survived: Anaximander is credited with having created one of the first maps of the world, which was circular in form and showed the known lands of the world grouped around the Aegean Sea at the center. This was all surrounded by the ocean. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Early+world+maps, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Paso Fino - Video Learning - WizScience.com
 
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The "Paso Fino" is a naturally gaited light horse breed dating back to horses imported to the Caribbean from Spain. Pasos are prized for their smooth, natural, four-beat, lateral ambling gait; they are used in many disciplines, but are especially popular for trail riding. In the United States two main groups of horses are popularly called "Paso Fino:" One, also known as the Pure Puerto Rican Paso Fino , originated in Puerto Rico. The other, often called the Colombian Paso Fino or Colombian Criollo Horse , developed in Colombia. Though from similar Spanish ancestors, the two groups developed independently of one another in their home nations. These two groups have been frequently crossbred in the United States and Europe. In recent years, a trend has developed favoring preservation breeding to preserve the undiluted bloodlines of each group. The Paso Fino name means 'fine step'. The Paso Fino is a blend of the Barb, Spanish Jennet, and Andalusian horse and was bred by Spanish land owners in Puerto Rico and Colombia to be used in the plantations because of their endurance and comfortable ride. All Pasos share their heritage with the Peruvian Paso, the American Mustangs, and other descendants of Colonial Spanish Horses. Puerto Rican and Colombian horses, as well as Paso Finos from Cuba and other tropical countries, have been interbred frequently in the United States to produce the modern American Paso Fino show horse. On the second voyage of Christopher Columbus from Spain to the Americas in 1493, he disembarked with his soldiers, 20 horses and 5 mares on the island of Borinquen at the bay of Aguada , and gave the region the name San Juan Bautista. Soon after, in May 1509, the first governor of the island, Juan Ponce de León, brought horses to Puerto Rico from his hacienda, El Higuey, located on the neighboring island of La Española . Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Paso+Fino, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Snake scales - Video Learning - WizScience.com
 
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"Snakes", like other reptiles, have a skin covered in "scales". Snakes are entirely covered with scales or scutes of various shapes and sizes, known as snakeskin as a whole. Scales protect the body of the snake, aid it in locomotion, allow moisture to be retained within, alter the surface characteristics such as roughness to aid in camouflage, and in some cases even aid in prey capture . The simple or complex colouration patterns are a property of the underlying skin, but the folded nature of scaled skin allows bright skin to be concealed between scales then revealed in order to startle predators. Scales have been modified over time to serve other functions such as 'eyelash' fringes, and protective covers for the eyes with the most distinctive modification being the "rattle" of the North American rattlesnakes. Snakes periodically moult their scaly skins and acquire new ones. This permits replacement of old worn out skin, disposal of parasites and is thought to allow the snake to grow. The arrangement of scales is used to identify snake species. Snakes have been part and parcel of culture and religion. Vivid scale patterns have been thought to have influenced early art. The use of snake-skin in manufacture of purses, apparel and other articles led to large-scale killing of snakes, giving rise to advocacy for use of artificial snake-skin. Snake scales are also to be found as motifs in fiction, art and films. The scales of a snake primarily serve to reduce friction as it moves, since friction is the major source of energy loss in snake locomotion. The ventral scales, which are large and oblong, are especially low-friction, and some arboreal species can use the edges to grip branches. Snake skin and scales help retain moisture in the animal's body. Snakes pick up vibrations from both the air and the ground, and can differentiate the two, using a complex system of internal resonances . Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Snake+scales, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Evolution of the horse - Video Learning - WizScience.com
 
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The "evolution of the horse" occurred over a period of 50 million years, transforming the small, dog-sized, forest-dwelling "Eohippus" into the modern horse. Paleozoologists have been able to piece together a more complete outline of the evolutionary lineage of the modern horse than of any other animal. The horse belongs to the order Perissodactyla , the members of which all share hooved feet and an odd number of toes on each foot, as well as mobile upper lips and a similar tooth structure. This means that horses share a common ancestry with tapirs and rhinoceroses. The perissodactyls arose in the late Paleocene, less than 10 million years after the Cretaceous–Paleogene extinction event. This group of animals appears to have been originally specialized for life in tropical forests, but whereas tapirs and, to some extent, rhinoceroses, retained their jungle specializations, modern horses are adapted to life on drier land, in the much harsher climatic conditions of the steppes. Other species of "Equus" are adapted to a variety of intermediate conditions. The early ancestors of the modern horse walked on several spread-out toes, an accommodation to life spent walking on the soft, moist grounds of primeval forests. As grass species began to appear and flourish, the equids' diets shifted from foliage to grasses, leading to larger and more durable teeth. At the same time, as the steppes began to appear, the horse's predecessors needed to be capable of greater speeds to outrun predators. This was attained through the lengthening of limbs and the lifting of some toes from the ground in such a way that the weight of the body was gradually placed on one of the longest toes, the third. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Evolution+of+the+horse, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Canid hybrid - Video Learning - WizScience.com
 
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"Canid hybrids" are the result of interbreeding between different species of the canine family . They often occur in the wild, in particular between domestic or feral dogs and wild native canid. Members of the dog genus "Canis": gray wolves, domestic dogs, dingoes, Ethiopian wolves, coyotes, and golden jackals cannot interbreed with members of the wider dog family: the Canidae, such as South American canids, foxes, African wild dogs, bat-eared foxes or raccoon dogs; or, if they could, their offspring would be infertile. Members of the genus "Canis" can, however, all interbreed to produce fertile offspring, with two exceptions: the side-striped jackal and black-backed jackal. Although these two theoretically could interbreed with each other to produce fertile offspring, it appears they cannot hybridize successfully with the rest of the genus "Canis". When the differences in number and arrangement of chromosomes is too great, hybridization becomes less and less likely. The wolf, dingo, dog, coyote, and golden jackal diverged relatively recently, around three to four million years ago, and all have 78 chromosomes arranged in 39 pairs. This allows them to hybridize freely and produce fertile offspring. The side-striped jackal and black-backed jackal both have 74 chromosomes. Other members of the Canidae family, which diverged seven to ten million years ago, are less closely related to and cannot hybridize with the wolf-like canids; the red fox has 34 metacentric chromosomes and from 0 to 8 small B chromosomes, the raccoon dog has 42 chromosomes, the fennec fox has 64 chromosomes. The African wild dog, however, still has the same number, 78 chromosomes, as do the wolf-like canids but it has yet to hybridize with any of them. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Canid+hybrid, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Azteca horse - Video Learning - WizScience.com
 
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The "Azteca" is a horse breed from Mexico, with a subtype, called the "American Azteca", found in the United States. They are well-muscled horses that may be of any solid color, and the American Azteca may also have pinto coloration. Aztecas are known to compete in many western riding and some English riding disciplines. The Mexican registry for the original Azteca and the United States registries for the American Azteca have registration rules that vary in several key aspects, including ancestral bloodlines and requirements for physical inspections. The Azteca was first developed in Mexico in 1972, from a blend of Andalusian, American Quarter Horse and Mexican Criollo bloodlines. From there, they spread to the United States, where American Paint Horse blood was added. The three foundation breeds of the Azteca are the Andalusian , American Quarter Horse, and Mexican Criollo or "Criollo militar". They were chosen to produce a breed that combined athletic ability with a good temperament and certain physical characteristics. Azteca stallions and geldings measure between at the withers, while mares stand between . The ideal height is . Both sexes usually weigh from 1000 to. The facial profile of the breed is straight or convex and the neck slightly arched. Overall, they are well-muscled horses, with broad croup and chest, as well as long, sloping shoulders. Gaits are free and mobile, with natural collection derived from the Andalusian ancestry of the breed. The breed is found in all solid colors, although gray is most often seen. White markings are allowed on the face and lower legs by breed associations. The American Azteca registry also allows non-solid pinto coloration. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Azteca+horse, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Maritime pilot - Video Learning - WizScience.com
 
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A "pilot" is a mariner who manoeuvres ships through dangerous or congested waters, such as harbors or river mouths, and completes the berthing / unberthing operation of the ships by controlling the ship's manoeuvrability directly and the tugs and shore linesmen through a radio. Pilots are expert shiphandlers who possess detailed knowledge of local waterways. They are transported by high speed pilot boats or helicopter from shore to an inbound ship and from an outbound ship back ashore. Most ports have compulsory pilotage. Legally, the master has full responsibility for safe navigation of his vessel, even if a pilot is on board. If he has clear grounds that the pilot may jeopardise the safety of navigation, he can relieve him from his duties and ask for another pilot or, if not compulsory to have a pilot on board, navigate the vessel without one. Only in transit of the Panama Canal does the pilot have the full responsibility for the navigation of the vessel. In English Law, Section 742 of the Merchant Shipping Act 1894 defines a pilot as "any person not belonging to a ship who has the conduct thereof." In other words, someone other than a member of the crew who has control over the speed, direction, and movement of the ship. The current United Kingdom legislation governing pilotage is the Pilotage Act 1987. Pilotage is one of the oldest professions, as old as sea travel, and it is one of the most important in maritime safety. The oldest "recorded" history dates back to about the 7th century BC. The economic and environmental risk from today's large cargo ships makes the role of the pilot essential. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Maritime+pilot, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Maritime+pilot, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Fort Bridger - Video Learning - WizScience.com
 
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"Fort Bridger" was originally a 19th-century fur trading outpost established in 1842 on Blacks Fork of the Green River and later a vital resupply point for wagon trains on the Oregon Trail, California Trail and Mormon Trail. The Army established a military post here in 1858 during the Utah War until it was finally closed in 1890. A small town, Fort Bridger, Wyoming, remains near the fort and takes its name from it. The post was established by the mountain man Jim Bridger, after whom it is named, and Louis Vasquez. In 1845, Lanford Hastings published a guide entitled "The Emigrant's Guide to Oregon and California", which advised California emigrants to leave the Oregon Trail, at Fort Bridger, pass through the Wasatch Range, across the Great Salt Lake Desert, an 80-mile waterless drive, loop around the Ruby Mountains, and rejoin the California Trail about seven miles west of modern Elko . The ill-fated Donner Party followed that route, along which they were met by a rider sent by Hastings to deliver letters to traveling emigrants. On July 12, the Reeds and Donners were given one of these letters, in which among other messages, Hastings claimed to have "worked out a new and better road to California", and said he would be waiting at Fort Bridger to guide the emigrants along the new cutoff. With the arrival of the Mormon pioneers in 1847, disputes arose between Bridger and the new settlers. By 1853, a militia of Mormons was sent to arrest him for selling alcohol and firearms to the Native Americans, a violation of Federal Law. He escaped capture, temporarily returning to the East. Near the existing fort, the Mormons established their own Fort Supply the same year. In 1855, Mormons took over Fort Bridger, reportedly buying it from Bridger for $8,000 in gold coins. The Mormons claimed, over Bridger's denials, they had purchased the fort from Vasquez. There was a deed dated August 3, 1855, recorded October 21, 1858, in Salt Lake City in Records Book B. p. 128 that ostensibly sold Fort Bridger to the LDS Church. Bridger and Vasquez's name was signed by H. F. Morrell in the presence of Alinerin Grow and William Adams Hickman, purportedly pursuant to a power of attorney. Since Bridger was absent from the area in 1855, acting as guide for Sir St. George Gore, and absent a signed power of attorney from Bridger. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Fort+Bridger, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Metonic cycle - Video Learning - WizScience.com
 
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For astronomy and calendar studies, the "Metonic cycle" or "Enneadecaeteris" is a period of very close to 19 years that is remarkable for being nearly a common multiple of the solar year and the synodic month. The Greek astronomer Meton of Athens observed that a period of 19 years is almost exactly equal to 235 synodic months and, rounded to full days, counts 6,940 days. The difference between the two periods is only a few hours, depending on the definition of the year. Considering a year to be of this 6,940-day cycle gives a year length of 365 +  +  days , which is slightly more than 12 synodic months. To keep a 12-month lunar year in pace with the solar year, an intercalary 13th month would have to be added on seven occasions during the nineteen-year period . When Meton introduced the cycle around 432 BC, it was already known by Babylonian astronomers. A mechanical computation of the cycle is built into the Antikythera mechanism. The cycle was used in the Babylonian calendar, ancient Chinese calendar systems and the medieval computus . It regulates the 19-year cycle of intercalary months of the modern Hebrew calendar. At the time of Meton, axial precession had not yet been discovered, and he could not distinguish between sidereal years and tropical years . Most calendars, like the commonly used Gregorian calendar, are based on the tropical year and maintain the seasons at the same calendar times each year. Nineteen tropical years are about two hours shorter than 235 synodic months. The Metonic cycle's error is, therefore, one full day every 219 years, or 12.4 parts per million. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Metonic+cycle, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Australian Stumpy Tail Cattle Dog - Video Learning - WizScience.com
 
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The "Australian Stumpy Tail Cattle Dog" is a bobtailed, medium-sized breed of dog. The Australian Stumpy Tail Cattle Dog was developed in Australia to herd cattle, and descends from crosses between European herding dogs and the Australian dingo. The Australian Stumpy Tail Cattle Dog descended from Smithfield Cattle Dogs in England, which were brought to Australia in the early 19th century and crossed with the dingo. Records of working dogs are scarce from this time period, and there are several different accounts of the breed's development. One is that a drover named Timmins from Bathurst, New South Wales, crossed the Smithfield dogs with the dingo, producing a type of working dog called Timmin's Biters. In order to mute their dingo characteristics and make the dogs easier to handle, further crosses were made with Scottish smooth collies, producing speckled red and blue dogs that were often born tailless. In the book "A Dog Called Blue", author Noreen Clark makes the case that both the tailless Australian Stumpy Tail Cattle Dog and the Australian Cattle Dog descended from the same stock, called Halls Heelers, kept in the 1830s by a very large cattle operation run by Thomas Hall. The dogs which were also crosses of Smithfield Cattle Dogs and dingo, but the breeds diverged at some point in the late 19th century. Selective breeding of the tailless or short tailed dogs has fixed the characteristic of today's breed. A summary of both versions of the breed's history is found in the Fédération Cynologique Internationale breed standard. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Australian+Stumpy+Tail+Cattle+Dog, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Lowland paca - Video Learning - WizScience.com
 
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The "lowland paca" , also known as the "spotted paca", is a large rodent found in tropical and sub-tropical America, from East-Central Mexico to Northern Argentina. It is called ""paca"" in most of its range, but ""tepezcuintle"" in most of Mexico and Central America, ""pisquinte"" in northern Costa Rica, ""jaleb"" in the Yucatán peninsula, ""conejo pintado"" in Panamá, ""guanta"" in Ecuador, ""majás"" or ""picuro"" in Peru, ""jochi pintado"" in Bolivia, and ""boruga"" or ""guardatinaja"" in Colombia. It is also known as the ""gibnut"" in Belize, where it is prized as a game animal, ""labba"" in Guyana, ""lapa"" in Venezuela, and ""lappe"" on the island of Trinidad. There is much confusion in the nomenclature of this and related species; see agouti. In particular, the popular term "agouti" or "common agouti" normally refers to species of the distinct "Dasyprocta" genus . Sometimes the word "agouti" is also used for a polyphyletic grouping uniting the families Cuniculidae and Dasyproctidae, which, besides the pacas and common agoutis, includes also the acouchis . "Cuniculus" is the appropriate genus name instead of "Agouti" based on a 1998 ruling of the International Commission on Zoological Nomenclature as the Lowland Paca's genus. The word "paca" comes from a word in the Tupi language that designates the animal but also means "awaken, alert." "Tepezcuintle" is of Nahuatl origin, meaning mountain dog: "tepetl" = mountain; "itzquintli" = dog. The lowland paca has coarse fur without underfur, dark brown to black on the upper body and white or yellowish on the underbelly. It usually has three to five rows of white spots along its sides, against a dark grey background. It has thick strong legs, with four digits in the forefeet and five in the hind feet ; the nails function as hooves. The tail is short and hairless. The zygomatic arch is expanded laterally and dorsally and is used as a resonating chamber - a unique feature among mammals. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Lowland+paca, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Fulgurite - Video Learning - WizScience.com
 
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"Fulgurites" are classified generically as a variety of the mineraloid lechatelierite, although their absolute chemical composition is dependent on the physical and chemical properties of target material affected by the discharge of cloud-ground lightning. They are natural, commonly hollow assemblages of glassy, protocrystalline, and heterogeneously-microcrystalline tubes, crusts, slags, vesicular masses, and clusters of dielectric and refractory materials that often form during the discharge phase of lightning strikes propagating into silica-rich quartzose sand, mixed soil, clay, caliche and other carbonate-rich sediments, humic sediments, conductive biomass , or anthropogenic materials having similar compositions . Colloquially, they have been referred to as "petrified lightning". Fulgurites are homologous to Lichtenberg figures, which are the branching patterns produced on surfaces of insulators during dielectric breakdown by high-voltage discharges, such as lightning. Fulgurites are formed when lightning with a temperature of at least 1800 C melts silica or other common conductive and semiconductive minerals and substrates, fusing, vitrifying, oxidizing and reducing mineral grains and organic compounds; the fulgurite mass is the rapidly-quenched end-product. The temperature peak within a lightning channel, however, is known to exceed 30,000 K; in carbon-rich fulgurites, which clearly have achieved liquid phase, temperatures unquestionably have exceeded the first triple point of carbon , with sufficient pressure to produce planar deformation features, or "shock lamellae" in SiO 2 polymorphs. It is assumed that the process of fulguritization occurs over a timespan of the order of a single second, following the termination of the return stroke sequence, and leaves direct evidence of the dissipation path and its dispersion over the surface or into the earth. Pseudo-fulgurites can also be produced when the cables of a high voltage electrical distribution network are severed, discharging alternating current into a conductive surface beneath, producing a linear trace structurally-distinct from natural fulgurite distribution due to the alternating polarity and duration of discharge. Arcing from power lines due to direct lightning strikes and related surges can produce hybrid pseudo-fulgurites. It is a common and conceptually-limiting belief that is widely propagated that fulgurites are exclusively tubaceous, columnar structures forming in sand or sandy soil. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Fulgurite, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Fulgurite, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Boron - Video Learning - WizScience.com
 
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"Boron" is a chemical element with symbol "B" and atomic number 5. Because boron is produced entirely by cosmic ray spallation and not by stellar nucleosynthesis it is a low-abundance element in both the Solar system and the Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest proven boron deposits are in Turkey, which is also the largest producer of boron minerals. Chemically uncombined boron, which is classed as a metalloid, is found in small amounts in meteoroids, but is not found naturally on Earth. Industrially, very pure boron is produced with difficulty, as boron tends to form refractory materials containing small amounts of carbon or other elements. Several allotropes of boron exist: amorphous boron is a brown powder, and crystalline boron is black, extremely hard , and a poor conductor at room temperature. The primary use of elemental boron is to make boron filaments, which are used in a similar way to carbon fibers in some high-strength materials. Almost all boron use is as chemical compounds. About half of global consumption of boron compounds is as additives for glass fibers in boron-containing fiberglass used for insulation or as structural materials. The next leading use is to make boron polymers and ceramics, that play specialized roles as high-strength lightweight structural and refractory materials. Borosilicate glass glassware is used for its greater strength and breakage resistance than ordinary soda lime glass. Boron compounds are also used as fertilizers in agriculture, and in sodium perborate bleaches. In minor uses, boron is an important dopant for semiconductors, and boron-containing reagents are used as intermediates in the synthesis of organic fine chemicals. A few boron-containing organic pharmaceuticals are used, or are in study. Natural boron is composed of two stable isotopes, one of which has a number of uses as a neutron-capturing agent. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Boron, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Martian meteorite - Video Learning - WizScience.com
 
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A "Martian meteorite" is a rock that formed on the planet Mars and was then ejected from Mars by the impact of an asteroid or comet, and finally landed on the Earth. Of over 61,000 meteorites that have been found on Earth, 132 were identified as Martian . These meteorites are thought to be from Mars because they have elemental and isotopic compositions that are similar to rocks and atmosphere gases analyzed by spacecraft on Mars. On October 17, 2013, NASA reported, based on analysis of argon in the Martian atmosphere by the Mars Curiosity rover, that certain meteorites found on Earth thought to be from Mars were indeed from Mars. The term does not refer to meteorites found on Mars, such as Heat Shield Rock. On January 3, 2013, NASA reported that a meteorite, named "NWA 7034" , found in 2011 in the Sahara desert, was determined to be from Mars and found to contain ten times the water of other Mars meteorites found on Earth. The meteorite was determined to have formed 2.1 billion years ago during the Amazonian geologic period on Mars. By the early 1980s, it was obvious that the SNC group of meteorites were significantly different from most other meteorite types. Among these differences were younger formation ages, a different oxygen isotopic composition, the presence of aqueous weathering products, and some similarity in chemical composition to analyses of the Martian surface rocks in 1976 by the Viking landers. Several workers suggested these characteristics implied the origin of SNC meteorites from a relatively large parent body, possibly Mars . Then in 1983, various trapped gases were reported in impact-formed glass of the EET79001 shergottite, gases which closely resembled those in the Martian atmosphere as analyzed by Viking. These trapped gases provided direct evidence for a Martian origin. In 2000, an article by Treiman, Gleason and Bogard gave a survey of all the arguments used to conclude the SNC meteorites were from Mars. They wrote, "There seems little likelihood that the SNCs are not from Mars. If they were from another planetary body, it would have to be substantially identical to Mars as it now is understood." Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Martian+meteorite, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Wilkes Land crater - Video Learning - WizScience.com
 
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"Wilkes Land crater" is an informal term that may apply to two separate cases of conjectured giant impact craters hidden beneath the ice cap of Wilkes Land, East Antarctica. These are separated below under the heading "Wilkes Land anomaly" and "Wilkes Land mascon ", based on terms used in their principal published reference sources. A giant impact crater beneath the Wilkes Land ice sheet was first proposed by R. A. Schmidt in 1962 on the basis of the seismic and gravity discovery of the feature made by the U.S. Victoria Land Traverse in 1959–60 , and the data provided to Schmidt by J. G. Weihaupt, geophysicist of the VLT . Schmidt further considered the possibility that it might be the elusive source of tektites from the Australasian strewnfield. The hypothesis was detailed in a paper by J. G. Weihaupt in 1976. Evidence cited included a large negative gravity anomaly coincident with a subglacial topographic depression 243 kilometers across and having a minimum depth of 848 meters. The claims were challenged by C. R. Bentley in 1979. On the basis of a 2010 paper by J. G. Weihaupt et al., Bentley's challenge was proven to be incorrect, and the Earth Impact Database has now reclassified the Wilkes Land Anomaly from a "possible impact crater" to a "probable impact crater" on the basis of Weihaupt et al.'s paper. Several other potential impact crater sites have now been proposed by other investigators in the Ross Sea, West Antarctica, and the Weddell Sea. The Wilkes Land mass concentration is centered at and was first reported at a conference in May 2006 by a team of researchers led by Ralph von Frese and Laramie Potts of Ohio State University. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Wilkes+Land+crater, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Alexander Selkirk - Video Learning - WizScience.com
 
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"Alexander Selkirk" , also known as "Alexander Selcraig", was a Scottish sailor who spent more than four years as a castaway after being marooned on an uninhabited island in the South Pacific Ocean . An unruly youth, Selkirk joined buccaneering expeditions to the South Sea, including one commanded by William Dampier, which called in for provisions at the Juan Fernández Islands off Chile. Selkirk judged correctly that his craft, the "Cinque Ports", was unseaworthy, and asked to be left there. By the time he was rescued, he had become adept at hunting and making use of the resources he found on the island. His story of survival was widely publicised when he returned home and became a likely source of inspiration for the writer Daniel Defoe's fictional character Robinson Crusoe. The son of a shoemaker and tanner in Lower Largo, Fife, Scotland, Alexander Selkirk was born in 1676. In his youth he displayed a quarrelsome and unruly disposition. Summoned in August 1693 before the Kirk Session for his "indecent conduct in church", he "did not appear, being gone to sea." He was back at Largo in 1701, when he again came to the attention of church authorities for beating up his brothers. Early on he was engaged in buccaneering. In 1703, he joined an expedition of the English privateer and explorer William Dampier to the South Sea, setting sail from Kinsale in Ireland on 11 September. They carried "letters of marque" from the Lord High Admiral authorising their armed merchant ships to attack foreign enemies, as the War of the Spanish Succession was then going on between England and France. While Dampier was captain of the "St George," Selkirk served on the "Cinque Ports", "St George"s companion, as sailing master under Captain Thomas Stradling. By this time Selkirk must have had considerable experience at sea. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Alexander+Selkirk, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Vanadium - Video Learning - WizScience.com
 
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"Vanadium" is a chemical element with symbol "V" and atomic number 23. It is a hard, silvery grey, ductile and malleable transition metal. The element is found only in chemically combined form in nature, but once isolated artificially, the formation of an oxide layer stabilizes the free metal somewhat against further oxidation. Andrés Manuel del Río discovered compounds of vanadium in 1801 in Mexico by analyzing a new lead-bearing mineral he called "brown lead," and presumed its qualities were due to the presence of a new element, which he named "erythronium" since, upon heating, most of its salts turned from their initial color to red. Four years later, however, he was convinced by other scientists that erythronium was identical to chromium. Chlorides of vanadium were generated in 1830 by Nils Gabriel Sefström who thereby proved that a new element was involved, which he named "vanadium" after the Scandinavian goddess of beauty and fertility, Vanadís . Both names were attributed to the wide range of colors found in vanadium compounds. Del Rio's lead mineral was later renamed vanadinite for its vanadium content. In 1867 Henry Enfield Roscoe obtained the pure element. Vanadium occurs naturally in about 65 different minerals and in fossil fuel deposits. It is produced in China and Russia from steel smelter slag; other countries produce it either from the flue dust of heavy oil, or as a byproduct of uranium mining. It is mainly used to produce specialty steel alloys such as high-speed tool steels. The most important industrial vanadium compound, vanadium pentoxide, is used as a catalyst for the production of sulfuric acid. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Vanadium, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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HED meteorite - Video Learning - WizScience.com
 
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"HED meteorites" are a clan of achondrite meteorites. HED stands for "howardite–eucrite–diogenite". These achondrites came from a differentiated parent body and experienced extensive igneous processing not much different from the magmatic rocks found on Earth and for this reason they closely resemble terrestrial igneous rocks. HED meteorites are broadly divided into: Several subgroups of both eucrites and diogenites have been found. The HED meteorites account for about 5% of all falls, which is about 60% of all achondrites. These are all thought to have originated from the crust of the asteroid 4 Vesta, their differences being due to different geologic histories of the parent rock. Their crystallization ages have been determined to be between 4.43 and 4.55 billion years from radioisotope ratios. HED meteorites are differentiated meteorites, which were created by igneous processes in the crust of their parent asteroid. It is thought that the method of transport from 4 Vesta to Earth is as follows: # An impact on 4 Vesta ejected debris, creating small V-type asteroids. Either the asteroidal chunks were ejected as such, or were formed from smaller debris. Some of these small asteroids formed the Vesta family, while others were scattered somewhat further. This event is thought to have happened less than 1 billion years ago. There is an enormous impact crater on 4 Vesta covering much of the southern hemisphere which is the best candidate for the site of this impact. The amount of rock that was excavated there is many times more than enough to account for all known V-type asteroids. # Some of the more far-flung asteroid debris ended up in the 3:1 Kirkwood gap. This is an unstable region due to strong perturbations by Jupiter, and asteroids which end up here get ejected onto far different orbits on a timescale of about 100 million years. Some of these bodies are perturbed into near-Earth orbits forming the small V-type near-Earth asteroids such as e.g. 3551 Verenia, 3908 Nyx, or 4055 Magellan. # Later smaller impacts on these near-Earth objects dislodged rock-sized meteorites, some of which later struck Earth. On the basis of cosmic ray exposure measurements, it is thought that most HED meteorites arose from several distinct impact events of this kind, and spent from about 6 million to 73 million years in space before striking the Earth. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/HED+meteorite, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Precambrian - Video Learning - WizScience.com
 
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The "Precambrian" or "Pre-Cambrian"; sometimes abbreviated "pЄ" is the largest span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago to the beginning of the Cambrian Period, about million years ago , when hard-shelled creatures first appeared in abundance. The Precambrian is so named because it precedes the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria, the classical name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of geologic time. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history, and what is known has largely been discovered from the 1960s onwards. The Precambrian fossil record is poorer than that of the succeeding Phanerozoic, and those fossils present are of limited biostratigraphic use. This is because many Precambrian rocks have been heavily metamorphosed, obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata. It is thought that the Earth itself coalesced from material in orbit around the Sun roughly 4500 Ma, or 4.5 billion years ago , and may have been struck by a very large planetesimal shortly after it formed, splitting off material that formed the Moon . A stable crust was apparently in place by 4400 Ma, since zircon crystals from Western Australia have been dated at 4404 Ma. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Precambrian, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Tachyon - Video Learning - WizScience.com
 
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A "tachyon" or "tachyonic particle" is a hypothetical particle that always moves faster than light. The word comes from the pronounced "tachy ", meaning rapid. It was coined in 1967 by Gerald Feinberg. The complementary particle types are called luxon and bradyon , which both exist. The possibility of particles moving faster than light was first proposed by O. M. P. Bilaniuk, V. K. Deshpande, and E. C. G. Sudarshan in 1962, although the term they used for it was "meta-particle". Most physicists think that faster-than-light particles cannot exist because they are not consistent with the known laws of physics. If such particles did exist, they could be used to build a tachyonic antitelephone and send signals faster than light, which would lead to violations of causality. Potentially consistent theories that allow faster-than-light particles include those that break Lorentz invariance, the symmetry underlying special relativity, so that the speed of light is not a barrier. In the 1967 paper that coined the term, Feinberg proposed that tachyonic particles could be quanta of a quantum field with negative squared mass. However, it was soon realized that excitations of such imaginary mass fields do "not" in fact propagate faster than light, and instead represent an instability known as tachyon condensation. Nevertheless, negative squared mass fields are commonly referred to as "tachyons", and in fact have come to play an important role in modern physics. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Tachyon, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Mesosaurus - Video Learning - WizScience.com
 
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""Mesosaurus"" is an extinct genus of reptile from the Early Permian of southern Africa and South America. Along with the genera "Brazilosaurus" and "Stereosternum", it is a member of the family Mesosauridae and the order Mesosauria. "Mesosaurus" was long thought to have been one of the first marine reptiles, although new data suggests that at least those of Uruguay inhabited a hypersaline water body, rather than a typical marine environment. In any case, it had many adaptations to a fully aquatic lifestyle. It is usually considered to have been anapsid, although Friedrich von Huene considered that it was synapsid, and this hypothesis has been revived recently. "Mesosaurus" had a long skull that was larger than that of "Stereosternum" and had longer teeth. The teeth are angled outwards, especially those at the tips of the jaws. The bones of the postcranial skeleton are thick, having undergone pachyostosis. "Mesosaurus" is unusual among reptiles in that it possesses a cleithrum. A cleithrum is a type of dermal bone that overlies the scapula, and is usually found in more primitive bony fish and tetrapods. The head of the interclavicle of "Mesosaurus" is triangular, unlike those of other early reptiles, which are diamond-shaped. "Mesosaurus" was one of the first reptiles to return to the water after early tetrapods came to land in the Late Devonian or later in the Paleozoic. It was around 1 m in length, with webbed feet, a streamlined body, and a long tail that may have supported a fin. It probably propelled itself through the water with its long hind legs and flexible tail. Its body was also flexible and could easily move sideways, but it had heavily thickened ribs, which would have prevented it from twisting its body. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Mesosaurus, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Acoustic release - Video Learning - WizScience.com
 
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An "acoustic release" is an oceanographic device for the deployment and subsequent recovery of instrumentation from the sea floor, in which the recovery is triggered remotely by an acoustic command signal. A typical "release" consists of the hydrophone , the battery housing , and a hook which is opened to release the anchor by high-torque electrical motor. Early use of acoustic releases for oceanography are reported in the 1960s, when it was recognized that deep ocean currents could more accurately be measured with sea floor mounted rather than ship board instruments. An obvious means of recovery was the use of a surface marker buoy linked to the sea floor instrument, but in areas of high ship traffic or the presence of ice bergs, this proved problematic. The acoustic release became a method to solve that problem, allowing the current meters to remain unattended on the seafloor for weeks or more, until the research vessel returned and triggered the release of the instrument by remote command, allowing it to float to the surface. In the book "Descriptive Physical Oceanography", authors Pickard and Emery vividly describe the recovery phase: Upon returning to the general location of the deployed mooring the scientist will reactivate the acoustic system on the release and use it to better locate the mooring and assure its condition as being ready for release. When ready, the release or wire-cutting mechanism is activated and the mooring is free to rise to the surface. There are many tense moments while waiting for the mooring to come to the surface; it may be difficult to spot as it floats low in the water so it usually carries a radio transmitter and a light to assist in locating it. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Acoustic+release, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Remote sensing - Video Learning - WizScience.com
 
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"Remote sensing" is the acquisition of information about an object or phenomenon without making physical contact with the object and thus in contrast to on site observation. Remote sensing is a sub-field of geography. In modern usage, the term generally refers to the use of aerial sensor technologies to detect and classify objects on Earth by means of propagated signals . It may be split into active remote sensing or passive when information is merely recorded. Passive sensors gather radiation that is emitted or reflected by the object or surrounding areas. Reflected sunlight is the most common source of radiation measured by passive sensors. Examples of passive remote sensors include film photography, infrared, charge-coupled devices, and radiometers. Active collection, on the other hand, emits energy in order to scan objects and areas whereupon a sensor then detects and measures the radiation that is reflected or backscattered from the target. RADAR and LiDAR are examples of active remote sensing where the time delay between emission and return is measured, establishing the location, speed and direction of an object. Remote sensing makes it possible to collect data of dangerous or inaccessible areas. Remote sensing applications include monitoring deforestation in areas such as the Amazon Basin, glacial features in Arctic and Antarctic regions, and depth sounding of coastal and ocean depths. Military collection during the Cold War made use of stand-off collection of data about dangerous border areas. Remote sensing also replaces costly and slow data collection on the ground, ensuring in the process that areas or objects are not disturbed. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Remote+sensing, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Information society - Video Learning - WizScience.com
 
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An "information society" is a society where the creation, distribution, use, integration and manipulation of information is a significant economic, political, and cultural activity. Its main driver are digital information and communication technologies, which have resulted in an information explosion and are profoundly changing all aspects of social organization, including the economy, education, health, warfare, government and democracy. the People who have the means to partake in this form of society are sometimes called digital citizens. This is one of many dozen labels that have been identified to suggest that humans are entering a new phase of society. The markers of this rapid change may be technological, economic, occupational, spatial, cultural, or some combination of all of these. Information society is seen as the successor to industrial society. Closely related concepts are the post-industrial society , post-fordism, post-modern society, knowledge society, telematic society, Information Revolution, liquid modernity, and network society . There is currently no universally accepted concept of what exactly can be termed information society and what shall rather not so be termed. Most theoreticians agree that a transformation can be seen that started somewhere between the 1970s and today and is changing the way societies work fundamentally. Information technology goes beyond the internet, and there are discussions about how big the influence of specific media or specific modes of production really is. Kelvin Kasiwulaya and Walter Gomo allude that information societies are those that have intensified their use of IT for economic, social, cultural and political transformation. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Information+society, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Information+society, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Personal digital assistant - Video Learning - WizScience.com
 
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A "personal digital assistant" , also known as a "handheld PC", or "personal data assistant", is a mobile device that functions as a personal information manager. The term evolved from Personal Desktop Assistant, a software term for an application that prompts or prods the user of a computer with suggestions or provides quick reference to contacts and other lists. PDAs were largely discontinued in the early 2010s after the widespread adoption of highly capable, in particular iOS and Android-based, smartphones. Nearly all PDAs have the ability to connect to the Internet. A PDA has an electronic visual display, enabling it to include a web browser, all models also have audio capabilities enabling use as a portable media player, and also enabling most of them to be used as mobile phones. Most PDAs can access the Internet, intranets or extranets via Wi-Fi or Wireless Wide Area Networks. Most PDAs employ touchscreen technology. The first PDA was released in 1984 by Psion, the Organizer. Followed by Psion's Series 3, in 1991, which began to resemble the more familiar PDA style. It also had a full keyboard. The term "PDA" was first used on January 7, 1992 by Apple Computer CEO John Sculley at the Consumer Electronics Show in Las Vegas, Nevada, referring to the Apple Newton. In 1994, IBM introduced the first PDA with full mobile phone functionality, the IBM Simon, which can also be considered the first smartphone. Then in 1996, Nokia introduced a PDA with full mobile phone functionality, the 9000 Communicator, which became the world's best-selling PDA. The Communicator spawned a new category of PDAs: the "PDA phone", now called "smartphone". Another early entrant in this market was Palm, with a line of PDA products which began in March 1996. The terms "personal digital assistant" and "PDA" apply to smartphones but are not used in marketing, media, or general conversation to refer to devices such as the BlackBerry, iPad or iPhone. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Personal+digital+assistant, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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English Mastiff - Video Learning - WizScience.com
 
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The "English Mastiff" is a breed of extremely large dog perhaps descended from the ancient Alaunt and Pugnaces Britanniae, with a significant input from the Alpine Mastiff in the 19th century. Distinguishable by enormous size, massive head, and a limited range of colors, but always displaying a black mask, the Mastiff is noted for its gentle and loving nature. The lineage of modern dogs can be traced back to the early 19th century, the modern type was stabilised in the 1880s and refined since. Following a period of sharp decline, the Mastiff has increased its worldwide popularity. Throughout its history, the Mastiff has contributed to the development of a number of dog breeds, some generally known as Mastiff-type dogs, or, confusingly, just as "Mastiffs". With a massive body, broad skull and head of generally square appearance, it is the largest dog breed in terms of mass. Though the Irish Wolfhound and Great Dane are taller, they are not nearly as robust. The body is large with great depth and breadth, especially between the forelegs, causing these to be set wide apart. The AKC standard height for this breed is 30 in at the shoulder for males and 27.5 in at the shoulder for females. A typical male can weigh 150 -, a typical female can weigh 120 -, with large individuals often reaching 130 kg or more. The former standard specified the coat should be short and close-lying and the color is apricot-fawn, silver-fawn, fawn, or dark fawn-brindle, always with black on the muzzle, ears, and nose and around the eyes. Fluffy mastiffs are mastiffs that exhibit the recessive, long-haired fluffy phenotype, hence fluffy mastiffs. They are otherwise genetically sound, and in no way inferior to a short-haired English mastiff. The fluffy coat is however considered a fault in the show ring, so it's not a trait that reputable breeders particularly breed for or advertise. If the dam and sire dogs are both carriers of the fluffy trait, then one or two fluffies may crop up in a litter and they are sold on pet-quality contracts. They now have genetic testing available to screen for this gene. So with breeders screening for the fluffy carriers in their breeding program, the chances of fluffies in the litters is diminishing. Some breeders will refuse to breed any dog that turns out to be a fluffy carrier. Others think being a fluffy or fluffy carrier is preferable to bad structure, and will include fluffies in their breeding program. The Fluffy trait does however decrease the amount of drool the dog produces. Though almost all Mastiffs are categorized as droolers, the English "Fluffy" Mastiff is not included in this group. They are gentle giants that are well behaved due to their extreme size. Along with being a joyful family pet they also are determined home defenders. They will protect house and family members with deep growls and very loud barks, though bites by mastiffs are extremely rare. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/English+Mastiff, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Epididymis - Video Learning - WizScience.com
 
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The "epididymis" is a tube that connects a testicle to a vas deferens in the male reproductive system. It is present in all male reptiles, birds, and mammals. It is a single, narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens. The epididymis can be divided into three main regions: In reptiles, there is an additional canal between the testis and the head of the epididymis and which receives the various efferent ducts. This is, however, absent in all birds and mammals. The epididymis is covered by a two layered pseudostratified epithelium. The epithelium is separated by a basement membrane from the connective tissue wall which has smooth muscle cells. The major cell types in the epithelium are: The stereocilia of the epididymis are structures which aid in absorption. They are long cytoplasmic projections that have no motility. Unlike the stereocilia of the inner ear, which play a role in hearing, stereocilia in the epididymis are more like the long, absorptive microvilli of other epithelia. These membrane extensions increase the surface area of the cell, allowing for greater absorption and secretion. The stereocilia in the epididymis are shaped by an internal actin network with no microtubule structure, and unlike true cilia are non-motile. Because sperm are initially nonmotile as they leave the seminiferous tubules, large volumes of fluid are secreted to propel them to the epididymis. The core function of the stereocilia is to resorb 90% of this fluid as the spermatozoa start to become motile. This absorption creates a fluid current that moves the immobile sperm from the seminiferous tubules to the epididymis. Spermatozoa do not reach full motility until they reach the vagina, where the alkaline pH is neutralized by acidic vaginal fluids. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Epididymis, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Oxytocin - Video Learning - WizScience.com
 
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"Oxytocin" is a nonapeptide hormone in mammals.  It is also available as a medication. Oxytocin is normally produced in the hypothalamus and stored in the posterior pituitary gland. It plays a role in intimacy, sexual reproduction of both sexes, and during and after childbirth as well as social bonding. It is released in large amounts after distension of the cervix and uterus during labor and with stimulation of the nipples following childbirth. This helps with birth, maternal bonding, and lactation. Studies have looked at oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, and maternal behaviors. As a medication, it is used to cause contraction of the uterus, which is used to start labor, increase the speed of labor, and to stop bleeding following delivery. It is on the World Health Organization's List of Essential Medicines, a list of the most important medications needed in a basic health system. Oxytocin has peripheral actions, and also has actions in the brain. Its actions are mediated by specific, oxytocin receptors. The oxytocin receptor is a G-protein-coupled receptor that requires magnesium and cholesterol. It belongs to the rhodopsin-type group of G-protein-coupled receptors. The peripheral actions of oxytocin mainly reflect secretion from the pituitary gland. Oxytocin secreted from the pituitary gland cannot re-enter the brain because of the blood–brain barrier. Instead, the behavioral effects of oxytocin are thought to reflect release from centrally projecting oxytocin neurons, different from those that project to the pituitary gland, or that are collaterals from them. Oxytocin receptors are expressed by neurons in many parts of the brain and spinal cord, including the amygdala, ventromedial hypothalamus, septum, nucleus accumbens, and brainstem. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Oxytocin, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Sundial - Video Learning - WizScience.com
 
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A "sundial" is a device that tells the time of day by the apparent position of the Sun in the sky. In common designs such as the horizontal sundial, the sun casts a shadow from its "style" onto a surface marked with lines indicating the hours of the day. The style is the time-telling edge of the "gnomon", often a thin rod or a sharp, straight edge. As the sun appears to move across the sky, the shadow-edge aligns with different hour-lines. Those sundials that directly measure the sun's hour-angle by the shadow of an edge must have that edge parallel to the axis of the Earth's rotation to tell the correct time throughout the year. The style's angle from the horizontal will thus equal the sundial's geographical latitude. It is common for inexpensive mass-produced decorative sundials to have incorrect hour angles, which cannot be adjusted to tell correct time. There are different types of sundials. Some sundials use a shadow or the edge of a shadow while others use a line or spot of light to indicate the time. The shadow-casting object, known as a "gnomon", may be a long thin rod, or other object with a sharp tip or a straight edge. Sundials employ many types of gnomon. The gnomon may be fixed or moved according to the season. It may be oriented vertically, horizontally, aligned with the Earth's axis, or oriented in an altogether different direction determined by mathematics. With sundials using light to indicate time, a line of light may be formed by allowing the sun's rays through a thin slit or focusing them through a cylindrical lens. A spot of light may be formed by allowing the sun's rays to pass through a small hole or by reflecting them from a small circular mirror. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Sundial, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Temperature-dependent sex determination - Video Learning - WizScience.com
 
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"Temperature-dependent sex determination" is a type of environmental sex determination in which the temperatures experienced during embryonic development determine the sex of the offspring. It is most prevalent and common among amniote vertebrates that are classified under the reptile class. TSD differs from the chromosomal sex-determination systems common among vertebrates. It is a type of environmental sex determination ; in other ESD systems, some factors such as population determine the sex of organisms . TSD was also thought to occur in some megapodes, such as the Australian brushturkey; however, their offspring sex ratios appear to result from temperature-dependent embryo mortality rather than from TSD. The eggs are affected by the temperature at which they are incubated during the middle one-third of embryonic development. This critical period of incubation is known as the thermosensitive period . The specific time of sex-commitment is known due to several authors resolving histological chronology of sex differentiation in the gonads of turtles with TSD. The thermosensitive, or temperature-sensitive, period is the point during development at which sex determination occurs in temperature-dependent sex determination systems, such as those present in alligators and turtles. Occurring during the middle third of incubation, the TSP lasts for 7–15 days, species-dependent. The temperature must be maintained during this time for a certain sex to be determined; often the differences between temperatures required to produce each sex are very slight and during the TSP, sex is susceptible to change with temperature. After this period, however, sex cannot be reversed . Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Temperature-dependent+sex+determination, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Brown anole - Video Learning - WizScience.com
 
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The "brown anole" , also known as the "Bahaman anole" or "De la Sagra's Anole", is a lizard native to Cuba and the Bahamas. It has been widely introduced elsewhere, by being sold as a pet lizard, and is now found in Florida and as far north in the United States as southern Georgia, Texas, Hawaii, Southern California. It has also been introduced to other Caribbean islands and Taiwan in Asia. This species is highly invasive. In its introduced range, it reaches exceptionally high population densities, is capable of expanding its range very quickly, and both outcompetes and consumes many species of native lizards. The brown anole's introduction into the United States in the early 1970s has altered the behavior and triggered a negative effect on populations of the native Carolina anole , which have generally been relegated to the treetops. The brown anole is normally a light brown color with darker brown to black markings on its back, and several tan to light color lines on its sides. Like other anoles, it can change color, in this case a darker brown to black. Its dewlap ranges from yellow to orange-red. The males can grow as large as their green anole male counterparts, around 17.8 – long, with some individuals topping 22.9 cm. The females are also around the size of female green anoles: 7.6 –. The male brown anole's head is smaller than that of the male green anole. Also, the brown anole's tail has a ridge that travels all the way up to behind the head, a feature the green anole lacks. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Brown+anole, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Christa McAuliffe - Video Learning - WizScience.com
 
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"Sharon Christa Corrigan McAuliffe" was an American teacher from Concord, New Hampshire, and was one of the seven crew members killed in the Space Shuttle "Challenger" explosion. She received her bachelor's degree in education and history from Framingham State College in 1970, and also a master's in education supervision and administration from Bowie State University in 1978. She took a teaching position as a social studies teacher at Concord High School in New Hampshire in 1983. In 1985, she was selected from more than 11,000 applicants to participate in the NASA Teacher in Space Project and was scheduled to become the first teacher in space. As a member of mission STS-51-L, she was planning to conduct experiments and teach two lessons from Space Shuttle "Challenger". On January 28, 1986, the shuttle broke apart 73 seconds after launch. After her death, schools and scholarships were named in her honor, and in 2004 she was posthumously awarded the Congressional Space Medal of Honor. McAuliffe was born Sharon Christa Corrigan on September 2, 1948, in Boston, Massachusetts. She was the eldest of the five children of accountant Edward Christopher Corrigan of Irish descent and Grace Mary Corrigan , a substitute teacher, whose father was of Lebanese Maronite descent. McAuliffe was a great niece of Lebanese-American historian Philip Khuri Hitti. She was known by her middle name from an early age, although in later years she signed her name "S. Christa Corrigan", and eventually "S. Christa McAuliffe". Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Christa+McAuliffe, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Sergeant Stubby - Video Learning - WizScience.com
 
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"Sergeant Stubby" , has been called the most decorated war dog of World War I and the only dog to be nominated for rank and then promoted to sergeant through combat, a claim for which there is no official documentary evidence, but is recognized in connection with an exhibition at the Smithsonian Institution. He was the official mascot of the 102nd Infantry, assigned to the 26th Division. Stubby served for 18 months and participated in seventeen battles on the Western Front. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and once caught a German soldier by the seat of his pants, holding him there until American soldiers found him. Back home his exploits were front page news of every major newspaper. Stubby was described in contemporaneous news items as a Bull Terrier or Boston Terrier. Describing him as a dog of "uncertain breed", Ann Bausum wrote that "The brindle-patterned pup probably owed at least some of his parentage to the evolving family of Boston Terriers, a breed so new that even its name was in flux: Boston Round Heads, American Bull Terriers, and Boston Bull Terriers." Stubby was found wandering the grounds of Yale University campus in New Haven, Connecticut in July 1917 while members of the 102nd Infantry were training. The dog hung around as the men drilled and one soldier, Corporal Robert Conroy, developed a fondness for the dog. When it came time for the outfit to ship out, Conroy hid Stubby on board the troop ship. As they were getting off the ship in France, he hid Stubby under his overcoat without detection. Upon discovery by Conroy's commanding officer, Stubby saluted him as he had been trained to in camp, and the commanding officer allowed the dog to stay on board. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Sergeant+Stubby, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Chlamydia infection - Video Learning - WizScience.com
 
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"Chlamydia infection" is a common sexually transmitted infection in humans caused by the bacterium "Chlamydia trachomatis". The term "Chlamydia infection" can also refer to infection caused by any species belonging to the bacterial family "Chlamydiaceae". "C. trachomatis" is found only in humans. Chlamydia is a major infectious cause of human genital and eye disease. Chlamydia infection is one of the most common sexually transmitted infections worldwide; it is estimated that about 1 million individuals in the United States are infected with chlamydia. "C. trachomatis" is naturally found living only inside human cells. Chlamydia can be transmitted during vaginal, anal, or oral sex, and can be passed from an infected mother to her baby during childbirth. Between half and three-quarters of all women who have a chlamydial infection of the cervix have an inflamed cervix without symptoms and may not realize they are infected. In men, infection by C. trachomatis can lead to inflammation of the penile urethra causing a white discharge from the penis with or without a burning sensation during urination. Occasionally, the condition spreads to the upper genital tract in women or to the epididymis in men . Chlamydia infection can be effectively cured with antibiotics. If left untreated, chlamydial infections can cause serious reproductive and other health problems with both short-term and long-term consequences. Research is ongoing in the prevention of this infection. Chlamydia conjunctivitis or trachoma is a common cause of blindness worldwide. The World Health Organization estimates that it accounted for 15% of blindness cases in 1995, but only 3.6% in 2002. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Chlamydia+infection, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Environmental impact of aviation - Video Learning - WizScience.com
 
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The "environmental impact of aviation" occurs because aircraft engines emit heat, noise, particulates and gases which contribute to climate change and global dimming. Despite emission reductions from automobiles and more fuel-efficient and less polluting turbofan and turboprop engines, the rapid growth of air travel in recent years contributes to an increase in total pollution attributable to aviation. In the European Union, greenhouse gas emissions from aviation increased by 87% between 1990 and 2006. There is an ongoing debate about possible taxation of air travel and the inclusion of aviation in an emissions trading scheme, with a view to ensuring that the total external costs of aviation are taken into account. Like all human activities involving combustion, most forms of aviation release carbon dioxide and other greenhouse gases into the Earth's atmosphere, contributing to the acceleration of global warming and ocean acidification. These concerns are highlighted by the present volume of commercial aviation and its rate of growth. Globally, about 8.3 million people fly daily , twice the total in 1999. U.S. airlines alone burned about 16.2 billion gallons of fuel during the twelve months between October 2013 and September 2014. In addition to the CO 2 released by most aircraft in flight through the burning of fuels such as Jet-A or Avgas , the aviation industry also contributes greenhouse gas emissions from ground airport vehicles and those used by passengers and staff to access airports, as well as through emissions generated by the production of energy used in airport buildings, the manufacture of aircraft and the construction of airport infrastructure. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Environmental+impact+of+aviation, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Plesiosauria - Video Learning - WizScience.com
 
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The "Plesiosauria" or "plesiosaurs" are an order or clade of Mesozoic marine reptiles , belonging to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period, possibly in the Rhaetian stage, about 205 million years ago. They became especially common during the Jurassic Period, thriving until their disappearance due to the Cretaceous–Paleogene extinction event at the end of the Cretaceous Period, about 66 million years ago. They had a worldwide oceanic distribution. Plesiosaurs were among the first fossil reptiles discovered. In the beginning of the nineteenth century, scientists realised how distinctive their build was and they were named as a separate order in 1835. The first plesiosaurian genus, the eponymous "Plesiosaurus", was named in 1821. Since then, more than a hundred valid species have been described. In the early twenty-first century, the number of discoveries has increased, leading to an improved understanding of their anatomy, relationships and way of life. Plesiosaurs had a broad flat body and a short tail. Their limbs had evolved into four long flippers, which were powered by strong muscles attached to wide bony plates formed by the shoulder girdle and the pelvis. The flippers made a flying movement through the water. Plesiosaurs breathed air, and bore live young; there are indications that they were warm-blooded. Plesiosaurs showed two main morphological types. Some species, with the "plesiosauromorph" build, had long necks and small heads; these were relatively slow and caught small sea animals. Other species, some of them reaching a length of up to seventeen metres, had the "pliosauromorph" build with a short neck and a large head; these were apex predators, fast hunters of large prey. The two types are related to the traditional strict division of the Plesiosauria into two suborders, the long-necked Plesiosauroidea and the short-neck Pliosauroidea. Modern research, however, indicates that several "long-necked" groups might have had some short-necked members or vice versa. Therefore the purely descriptive terms "plesiosauromorph" and "pliosauromorph" have been introduced, which do not imply a direct relationship. "Plesiosauroidea" and "Pliosauroidea" today have a more limited meaning. The term "plesiosaur" is properly used to refer to the Plesiosauria as a whole, but informally it is sometimes meant to indicate only the long-necked forms, the old Plesiosauroidea. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Plesiosauria, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Heck cattle - Video Learning - WizScience.com
 
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"Heck cattle" are a hardy breed of domestic cattle. These cattle are the result of an attempt to breed back the extinct aurochs from modern aurochs-derived cattle in the 1920s and 1930s. Controversy revolves around methodology and success of the program. There are considerable differences between Heck cattle and the aurochs. Furthermore, there are other cattle breeds which resemble their wild ancestors at least as much as Heck cattle. Heck cattle originated in Germany in the 1920s and 1930s in an attempt to breed back domestic cattle to their ancestral form: the aurochs . In the first years of the Weimar Republic, the brothers Heinz and Lutz Heck independently started their extensive breeding-back programmes. Their motivation behind that was to rescue the aurochs from oblivion because it was constantly confused with the wisent, the other large bovine of Holocene Europe. The Heck brothers believed that creating a look-alike and showing both species next to each other will help to show the difference between the two species to a broader public. Apart from that, they believed they were able to reconstruct the species and therefore to correct the mistake man did when killing the species off. Heinz was the director of the Hellabrunn Zoological Gardens in Munich and Lutz of the Berlin Zoological Gardens. Only eleven years after they started their breeding experiments, just as the Weimar Republic was drawing to a close, they each announced their success. Both brothers used a different selection of cattle breeds in their breeding-back attempts. For example, Lutz Heck used Spanish fighting bulls, while Heinz did not. The Berlin breed seemingly did not survive the Second World War, so all modern Heck cattle go back to the experiments of Heinz Heck in Munich. Those ancestral breeds include: Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Heck+cattle, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Archelon - Video Learning - WizScience.com
 
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""Archelon"" is a genus of extinct sea turtles, the largest that have ever been documented, and the second largest turtles documented, behind "Stupendemys". The first specimen of "Archelon" was collected from the Campanian-age Pierre Shale of South Dakota by Dr. G.R. Wieland in 1895 and described by him the following year . The largest "Archelon" fossil, found in the Pierre Shale of South Dakota in the 1970s, measures more than 4 m long, and about 4.9 m wide from flipper to flipper. It was a marine turtle, whose closest living relative in the present day is the leatherback sea turtle. "Archelon" lived at a time when a shallow sea covered most of central North America. Most of the known remains have been found in South Dakota and Wyoming. Though anatomically similar to the earlier species "Protostega gigas", it was much larger. Unlike most modern turtles, "Archelon" did not have a solid shell, but instead had a skeletal framework supporting a leathery or bony carapace. Other distinguishing features include a pointed tail, a narrow skull, a relatively narrow, high-vaulted shell, and a pronounced overbite. The live weight of an "Archelon ischyros" is estimated at more than 2200 kg . They probably had a very strong bite, and were optimized for feeding on pelagic mollusks such as squid. The specimen exhibited by the Museum of Natural History in Vienna is estimated to have lived to be a century old, and may have died while brumating on the ocean floor. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Archelon, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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Science, technology, society and environment education - Video Learning - WizScience.com
 
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"Science, technology, society and environment education", originates from the science technology and society movement in science education. This is an outlook on science education that emphasizes the teaching of scientific and technological developments in their cultural, economic, social and political contexts. In this view of science education, students are encouraged to engage in issues pertaining to the impact of science on everyday life and make responsible decisions about how to address such issues The STS movement has a long history in science education reform, and embraces a wide range of theories about the intersection between science, technology and society . Over the last twenty years, the work of Peter Fensham, the noted Australian science educator, is considered to have heavily contributed to reforms in science education. Fensham's efforts included giving greater prominence to STS in the school science curriculum . The key aim behind these efforts was to ensure the development of a broad-based science curriculum, embedded in the socio-political and cultural contexts in which it was formulated. From Fensham's point of view, this meant that students would engage with different viewpoints on issues concerning the impact of science and technology on everyday life. They would also understand the relevance of scientific discoveries, rather than just concentrate on learning scientific facts and theories that seemed distant from their realities . However, although the wheels of change in science education had been set in motion during the late 1970s, it was not until the 1980s that STS perspectives began to gain a serious footing in science curricula, in largely Western contexts . This occurred at a time when issues such as, animal testing, environmental pollution and the growing impact of technological innovation on social infrastructure, were beginning to raise ethical, moral, economic and political dilemmas . There were also concerns among communities of researchers, educators and governments pertaining to the general public's lack of understanding about the interface between science and society . In addition, alarmed by the poor state of scientific literacy among school students, science educators began to grapple with the quandary of how to prepare students to be informed and active citizens, as well as the scientists, medics and engineers of the future . Hence, STS advocates called for reforms in science education that would equip students to understand scientific developments in their cultural, economic, political and social contexts. This was considered important in making science accessible and meaningful to all students—and, most significantly, engaging them in real world issues . Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Science%2c+technology%2c+society+and+environment+education, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.
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