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Herrerasaurus - Video Learning - WizScience.com
 
02:09
""Herrerasaurus"" was one of the earliest dinosaurs. Its name means "Herrera's lizard", after the rancher who discovered the first specimen. All known fossils of this carnivore have been discovered in rocks of Carnian age in northwestern Argentina. The type species, ""Herrerasaurus ischigualastensis"", was described by Osvaldo Reig in 1963 and is the only species assigned to the genus. "Ischisaurus" and "Frenguellisaurus" are synonyms. For many years, the classification of "Herrerasaurus" was unclear because it was known from very fragmentary remains. It was hypothesized to be a basal theropod, a basal sauropodomorph, a basal saurischian, or not a dinosaur at all but another type of archosaur. However, with the discovery of an almost complete skeleton and skull in 1988, "Herrerasaurus" has been classified as either an early theropod or an early saurischian in at least five recent reviews of theropod evolution, with many researchers treating it at least tentatively as the most primitive member of Theropoda. It is a member of the Herrerasauridae, a family of similar genera that were among the earliest of the dinosaurian evolutionary radiation. "Herrerasaurus" was a lightly built bipedal carnivore with a long tail and a relatively small head. Its length is estimated at 3 to 6 meters , and its hip height at more than 1.1 meters . It may have weighed around 210–350 kilograms . In a large specimen, at first thought to belong to a separate genus, "Frenguellisaurus", the skull measured 56 centimeters in length. Smaller specimens had skulls about 30 centimeters long. 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/Herrerasaurus, 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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Islam and cats - Video Learning - WizScience.com
 
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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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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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Abdomen - Video Learning - WizScience.com
 
02:04
"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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Ceramic materials - Video Learning - WizScience.com
 
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"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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mammals of West Virginia - Video Learning - WizScience.com
 
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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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Brown anole - Video Learning - WizScience.com
 
02:04
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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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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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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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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Continental crust - Video Learning - WizScience.com
 
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The "continental crust" is the layer of igneous, sedimentary, and metamorphic rocks which forms the continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called "sial" because there is more felsic, or granitic, bulk composition, which lies in contrast to the oceanic crust, called "sima" because of the mafic or basaltic rock. Consisting mostly of granitic rock, continental crust has a density of about 2.7 g/cm 3 and is less dense than the material of the Earth's mantle , which consists of ultramafic rock. Continental crust is also less dense than oceanic crust , though it is considerably thicker; mostly 25 to 70 km versus the average oceanic thickness of around 7–10 km. About 40% of the Earth's surface is now overlaid by continental crust. Continental crust makes up about 70% of the volume of Earth's crust. Because the surface of continental crust mainly lies above sea level, its existence allowed land life to evolve from marine life. Its existence also provides broad expanses of shallow water known as epeiric seas and continental shelves where complex metazoan life could become established during early Paleozoic time, in what is now called the Cambrian explosion. There is little evidence of continental crust prior to 3.5 bya, and there was relatively rapid development on shield areas consisting of continental crust between 3.0 and 2.5 bya. All continental crust ultimately derives from the fractional differentiation of oceanic crust over many eons. This process has been and continues today primarily as a result of the volcanism associated with subduction. 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/Continental+crust, 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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Bamboo blossom - Video Learning - WizScience.com
 
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"Bamboo blossom" is a natural phenomenon in which the bamboos of a place will blossom and become hung with bamboo seeds. In China and India, "bamboo blossom" was traditionally seen as a curse or an indication of a starvation coming. Bamboos usually have a life-cycle of around 40 to 80 years, varying among species. Normally, new bamboos grow up from bamboo shoots at the roots. At infrequent intervals for most species, they will start to blossom. After the blossom, the flowers produce fruit, which the Chinese called "bamboo rice". Then, the bamboo forest will die. Since a bamboo forest usually grows from a single bamboo, the death of bamboos occurs in a large area. Many bamboos species only flower at intervals as long as 65 or 120 years. These taxa exhibit mass flowering , with all plants in a particular "cohort" flowering over a several-year period. Any plant derived through clonal propagation from this cohort will also flower regardless of whether it has been planted in a different location. The longest mass flowering interval known is 130 years, and it is for the species "Phyllostachys bambusoides" . In this species, all plants of the same stock flower at the same time, regardless of differences in geographic locations or climatic conditions, and then the bamboo dies. The lack of environmental impact on the time of flowering indicates the presence of some sort of “alarm clock” in each cell of the plant which signals the diversion of all energy to flower production and the cessation of vegetative growth. This mechanism, as well as the evolutionary cause behind it, is still largely a mystery. 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/Bamboo+blossom, 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/Bamboo+blossom, 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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Flag of Wales - Video Learning - WizScience.com
 
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The "flag of Wales" consists of a red dragon passant on a green and white field. As with many heraldic charges, the exact representation of the dragon is not standardised and many renderings exist. The flag incorporates the Red Dragon of Cadwaladr, King of Gwynedd, along with the Tudor colours of green and white. It was used by Henry VII at the Battle of Bosworth in 1485 after which it was carried in state to St Paul's Cathedral. The red dragon was then included as a supporter of the Tudor royal arms to signify their Welsh descent. It was officially recognised as the Welsh national flag in 1959. The dragon as a major flag design element is shared with the flag of Bhutan. A dragon also appears on the badge of the George Cross on the flag of Malta. The Chinese flag also featured a dragon during the Qing Dynasty. The flag was granted official status in 1959, but the red dragon itself has been associated with Wales for centuries, though the origin of the adoption of the dragon symbol is now lost in history and myth. A possible theory is that the Romans brought the emblem to what is now Wales during their occupation of Britain in the form of the Draco standards borne by the Roman cavalry, itself inspired by the symbols of the Dacians or Parthians. The green and white stripes of the flag were additions by the House of Tudor, the Welsh dynasty that held the English throne from 1485 to 1603. Green and white are also the colours of the leek, another national emblem of Wales. 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/Flag+of+Wales, 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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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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Tarbosaurus - Video Learning - WizScience.com
 
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""Tarbosaurus"" is a genus of tyrannosaurid theropod dinosaur that flourished in Asia about 70 million years ago, at the end of the Late Cretaceous Period. Fossils have been recovered in Mongolia, with more fragmentary remains found further afield in parts of China. Although many species have been named, modern paleontologists recognize only one, "T. bataar", as valid. Some experts see this species as an Asian representative of the North American genus "Tyrannosaurus"; this would make the genus "Tarbosaurus" redundant. "Tarbosaurus" and "Tyrannosaurus", if not synonymous, are considered to be at least closely related genera. "Alioramus", also from Mongolia, is thought by some authorities to be the closest relative of "Tarbosaurus". Like most known tyrannosaurids, "Tarbosaurus" was a large bipedal predator, weighing up to five tonnes and equipped with about sixty large teeth. It had a unique locking mechanism in its lower jaw and the smallest forelimbs relative to body size of all tyrannosaurids, renowned for their disproportionately tiny, two-fingered forelimbs. "Tarbosaurus" lived in a humid floodplain criss-crossed by river channels. In this environment, it was an apex predator at the top of the food chain, probably preying on other large dinosaurs like the hadrosaur "Saurolophus" or the sauropod "Nemegtosaurus". "Tarbosaurus" is represented by dozens of fossil specimens, including several complete skulls and skeletons. These remains have allowed scientific studies focusing on its phylogeny, skull mechanics, and brain structure. 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/Tarbosaurus, 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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Christiaan Huygens - Video Learning - WizScience.com
 
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"Christiaan Huygens", FRS was a prominent Dutch mathematician and scientist. He is known particularly as an astronomer, physicist, probabilist and horologist. Huygens was a leading scientist of his time. His work included early telescopic studies of the rings of Saturn and the discovery of its moon Titan, the invention of the pendulum clock and other investigations in timekeeping. He published major studies of mechanics and optics, and a pioneer work on games of chance. Christiaan Huygens was born on 14 April 1629 in The Hague, into a rich and influential Dutch family, the second son of Constantijn Huygens. Christiaan was named after his paternal grandfather. His mother was Suzanna van Baerle. She died in 1637, shortly after the birth of Huygens' sister. The couple had five children: Constantijn , Christiaan , Lodewijk , Philips and Suzanna . Constantijn Huygens was a diplomat and advisor to the House of Orange, and also a poet and musician. His friends included Galileo Galilei, Marin Mersenne and René Descartes. Huygens was educated at home until turning sixteen years old. He liked to play with miniatures of mills and other machines. His father gave him a liberal education: he studied languages and music, history and geography, mathematics, logic and rhetoric, but also dancing, fencing and horse riding. In 1644 Huygens had as his mathematical tutor Jan Jansz de Jonge Stampioen, who set the 15-year-old a demanding reading list on contemporary science. Descartes was impressed by his skills in geometry. 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/Christiaan+Huygens, 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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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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Hereford (cattle) - Video Learning - WizScience.com
 
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"Hereford" is a beef cattle breed, widely used both in intemperate areas and temperate areas, mainly for meat production. Originally from Herefordshire, England, United Kingdom, more than five million pedigree Hereford cattle now exist in over 50 countries. The Hereford cattle export trade began from United Kingdom in 1817, starting in Kentucky, United States, spreading across the United States and Canada through Mexico to the great beef-raising countries of South America. Today, Hereford cattle dominate the world scene from Australasia to the Russian steppes. They can be found in Israel, Japan and throughout continental Europe and Scandinavia. They are found in the temperate parts of Canada, the United States and Russia, as well as the temperate parts of Australia, the centre and east of Argentina, in Uruguay, and New Zealand, where they make up the largest proportion of registered cattle. They originally found great popularity among ranchers of the American Southwest, testament to the hardiness of the breed; while originating in cool, moist Britain, they have proven to thrive in much harsher climates on nearly every continent. The World Hereford Council is based in the United Kingdom; the Secretary General, Mrs. Jan Wills, is from New Zealand. There are currently 17 member countries with 20 Hereford societies and 10 nonmember countries, with a total of eight societies. Until the 18th century, the cattle of the Herefordshire area were similar to other cattle of southern England, being wholly red with a white switch, similar to the modern North Devon and Sussex breeds. During the 18th and early 19th centuries, other cattle were used to create a new type of draught and beef cattle which at first varied in color, different herds ranging from yellow to grey and light brown, and with varying amounts of white. However, by the end of the 18th century the white face characteristic of the modern breed was well established, and the modern color was established during the 19th century. 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/Hereford+(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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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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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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Plasma propulsion engine - Video Learning - WizScience.com
 
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A "plasma propulsion engine" is a type of electric propulsion that generates thrust from a quasi-neutral plasma. This is in contrast to ion thruster engines, which generates thrust through extracting an ion current from plasma source, which is then accelerated to high velocities using grids/anodes. These exist in many forms . Plasma thrusters do not typically use high voltage grids or anodes/ cathodes to accelerate the charged particles in the plasma, but rather uses currents and potentials which are generated internally in the plasma to accelerate the plasma ions. While this results in a lower exhaust velocities by virtue of the lack of high accelerating voltages, this type of thruster has a number of interesting advantages. The lack of high voltage grids of anodes removes a possible limiting element as a result of grid ion erosion. The plasma exhaust is 'quasi- neutral', which means that ion and electrons exist in equal number, which allows simply ion- electron recombination in the exhaust to neutralise the exhaust plume, removing the need for an electron gun . This type of thruster often generates the source plasma using radio frequency of microwave energy, using an external antenna. This fact, combined with the absence of hollow cathodes allows the intriguing possibility of being able to use this type of thruster on a huge range of propellants, from argon, to carbon dioxide, air mixtures to astronaut urine. Plasma engines are better suited for long-distance interplanetary space travel missions. 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+propulsion+engine, 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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North American dinosaurs - Video Learning - WizScience.com
 
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This is a "list of non-avian dinosaurs" whose remains have been recovered from "North America". North America has a rich dinosaur fossil record with great diversity of dinosaurs. This may not mean the non-avian dinosaurs were more diverse or abundant; it may be simply because substantial resources have been devoted to the North American fossil record. During the Triassic period, dinosaurs such as "Coelophysis", "Chindesaurus", "Gojirasaurus", and "Tawa" lived in North America. Fossils of "Tawa" have also been found in South America, which has important indications about paleogeography. During the Early Jurassic Period, dinosaurs such as "Dilophosaurus", "Anchisaurus", "Ammosaurus", "Megapnosaurus" , and the early thyreophoran "Scutellosaurus" lived in North America. The latter is believed to have been the ancestor of all stegosaurs and ankylosaurs. The Middle Jurassic is the only poorly represented time period in North America, although several Middle Jurassic localities are known from Mexico. Footprints, eggshells, teeth, and fragments of bone representing theropods, sauropods, and ornithopods have been found, but none of them are diagnostic to the genus level. The Late Jurassic of North America, however, is the exact opposite of the Middle Jurassic. The Late Jurassic Morrison Formation is found in several U.S. states, including Colorado, Utah, Wyoming, Montana, New Mexico, Oklahoma, South Dakota, and Texas. It is notable as being the most fertile single source of dinosaur fossils in the world. The roster of dinosaurs from the Morrison is impressive. Among the theropods, "Allosaurus", "Saurophaganax", "Torvosaurus", "Ceratosaurus", "Coelurus", "Ornitholestes", "Tanycolagreus", "Stokesosaurus", and "Marshosaurus" are found in the Morrison. An abundance of sauropods has been found there, including "Apatosaurus", "Diplodocus", "Barosaurus", "Brachiosaurus", "Camarasaurus", and "Amphicoelias", which is possibly the largest known dinosaur ever to exist. Two genera of stegosaurs, "Stegosaurus" and "Hesperosaurus", have been found there. Finally, ornithopods found in the Morrison include "Dryosaurus", "Camptosaurus", "Drinker", "Othnielia", and "Othnielosaurus". 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+North+American+dinosaurs, 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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Painted turtle - Video Learning - WizScience.com
 
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The "painted turtle" is the most widespread native turtle of North America. It lives in slow-moving fresh waters, from southern Canada to Louisiana and northern Mexico, and from the Atlantic to the Pacific. The turtle is the only species of the genus "Chrysemys", which is part of the pond turtle family Emydidae. Fossils show that the painted turtle existed 15 million years ago. Four regionally based subspecies evolved during the last ice age. The adult painted turtle female is 10 - long; the male is smaller. The turtle's top shell is dark and smooth, without a ridge. Its skin is olive to black with red, orange, or yellow stripes on its extremities. The subspecies can be distinguished by their shells: the eastern has straight-aligned top shell segments; the midland has a large gray mark on the bottom shell; the southern has a red line on the top shell; the western has a red pattern on the bottom shell. The turtle eats aquatic vegetation, algae, and small water creatures including insects, crustaceans, and fish. Although they are frequently consumed as eggs or hatchlings by rodents, canines, and snakes, the adult turtles' hard shells protect them from most predators. Reliant on warmth from its surroundings, the painted turtle is active only during the day when it basks for hours on logs or rocks. During winter, the turtle hibernates, usually in the mud at the bottom of water bodies. The turtles mate in spring and autumn. Females dig nests on land and lay eggs between late spring and mid-summer. Hatched turtles grow until sexual maturity: 2–9 years for males, 6–16 for females. 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/Painted+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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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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Altair - Video Learning - WizScience.com
 
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"Altair" is the brightest star in the constellation Aquila and the twelfth brightest star in the night sky. It is currently in the G-cloud. Altair is an A-type main sequence star with an apparent visual magnitude of 0.77 and is one of the vertices of the Summer Triangle . It is 16.7 light-years from Earth and is one of the closest stars visible to the naked eye. Altair rotates rapidly, with a velocity at the equator of approximately 286 km/s. A study with the Palomar Testbed Interferometer revealed that Altair is not spherical, but is flattened at the poles due to its high rate of rotation. Other interferometric studies with multiple telescopes, operating in the infrared, have imaged and confirmed this phenomenon. Altair is located 16.7 light-years from Earth and is one of the closest stars visible to the naked eye. Along with Beta Aquilae and Gamma Aquilae, it forms the well-known line of stars sometimes referred to as the "Family of Aquila" or "Shaft of Aquila". Altair is a type-A main sequence star with approximately 1.8 times the mass of the Sun and 11 times its luminosity. Altair possesses an extremely rapid rate of rotation; it has a rotational period of approximately 9 hours. For comparison, the equator of the Sun requires a little more than 25 days for a complete rotation. This rapid rotation forces Altair to be oblate; its equatorial diameter is over 20 percent greater than its polar diameter. Satellite measurements made in 1999 with the Wide Field Infrared Explorer showed that the brightness of Altair fluctuates slightly, varying by less than a thousandth of a magnitude. As a result, it was identified in 2005 as a Delta Scuti variable star. Its light curve can be approximated by adding together a number of sine waves, with periods that range between 0.8 and 1.5 hours. 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/Altair, 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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Jacob sheep - Video Learning - WizScience.com
 
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The "Jacob sheep" is a rare breed of small, piebald , polycerate sheep. Jacobs may have from two to six horns, but most commonly have four. The most common color is black and white. Jacobs are usually raised for their wool, meat, and hides. They are also kept as pets and ornamental animals, and have been used as guard animals to protect farm property from theft or vandalism and defend other livestock against predators. Generally referred to as an unimproved or heirloom breed , the Jacob is descended from an ancient Old World breed of sheep, although its exact origins remain unclear. Spotted polycerate sheep were documented in England by the mid–17th century, and were widespread a century later. Unlike most other old world breeds, the Jacobs of North America have not undergone extensive cross-breeding and selective breeding; their body habitus resembles that of a goat. Relative to their American counterparts, British Jacobs tend to be larger and heavier, and have lost many of their original characteristics through artificial selection. The origins of the Jacob are obscure, but it is certainly a very old breed. Piebald sheep have been described throughout history, appearing in works of art from the Far East, Middle East, and Mediterranean regions. A piebald breed of sheep probably existed in the Levant, specifically in the area that is now known as Syria, about three thousand years ago. Among the many accounts of ancient breeds of piebald sheep is the story of Jacob from the first book of the Hebrew Bible and the Christian Old Testament. According to the Book of Genesis , in what may be the earliest recorded attempt at selective breeding, Jacob took every speckled and spotted sheep from his father-in-law's flock and bred them. The Jacob is named for the Biblical figure of Jacob. The resulting breed may have accompanied the westward expansion of human civilization through Northern Africa, Sicily, Spain and eventually England. However, it was not until the 20th century when the breed acquired the name "Jacob sheep". 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/Jacob+sheep, 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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Cold cathode - Video Learning - WizScience.com
 
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A "cold cathode" is a cathode that is not electrically heated by a filament. A cathode may be considered "cold" if it emits more electrons than can be supplied by thermionic emission alone. It is used in gas-discharge lamps, such as neon lamps, discharge tubes, and some types of vacuum tube. The other type of cathode is a hot cathode, which is heated by electric current passing through a filament. A cold cathode does not necessarily operate at a low temperature: it is often heated to its operating temperature by other methods, such as the current passing from the cathode into the gas. A cold-cathode vacuum tube does not rely on external heating of an electrode to provide thermionic emission of electrons. Early cold-cathode devices included the Geissler tube and Plucker tube, and early cathode ray tubes. Study of the phenomena in these devices led to the discovery of the electron. Neon lamps are used both to produce light as indicators and for special-purpose illumination, and also as circuit elements displaying negative resistance. Addition of a trigger electrode to a device allowed the glow discharge to be initiated by an external control circuit; Bell Laboratories developed a "trigger tube" cold cathode device in 1936. Many types of cold-cathode switching tube were developed, including various types of thyratron, the krytron, cold cathode displays and others. Voltage regulator tubes rely on the relatively constant voltage of a glow discharge over a range of current, and were used to stabilize power supply voltages in tube-based instruments. A Dekatron is a cold-cathode tube with multiple electrodes that is used for counting. Each time a pulse is applied to a control electrode, a glow discharge moves to a step electrode; by providing ten electrodes in each tube and cascading the tubes, a counter system can be developed and the count observed by the position of the glow discharges. Counter tubes were used widely before development of integrated circuit counter devices. 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/Cold+cathode, 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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Quagga - Video Learning - WizScience.com
 
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The "quagga" is an extinct subspecies of plains zebra that lived in South Africa until the 19th century. It was long thought to be a distinct species, but genetic studies have shown it to be the southernmost subspecies of plains zebra. It is considered particularly close to Burchell's zebra. Its name is derived from its call, which sounds like "kwa-ha-ha". The quagga is believed to have been around 257 cm long and 125 – tall at the shoulder. It was distinguished from other zebras by its limited pattern of primarily brown and white stripes, mainly on the front part of the body. The rear was brown and without stripes, and therefore more horse-like. The distribution of stripes varied considerably between individuals. Little is known about the quagga's behaviour, but it may have gathered into herds of 30–50 individuals. Quaggas were said to be wild and lively, yet were also considered more docile than Burchell's zebra. They were once found in great numbers in the Karoo of Cape Province and the southern part of the Orange Free State in South Africa. Since Dutch settlement of South Africa began, the quagga was heavily hunted as it competed with domesticated animals for forage. While some individuals were taken to zoos in Europe, breeding programs were unsuccessful. The last wild population lived in the Orange Free State, and the quagga was extinct in the wild by 1878. The last captive specimen died in Amsterdam on 12 August 1883. Only one quagga was ever photographed alive and only 23 skins are preserved today. In 1984, the quagga was the first extinct animal to have its DNA analysed, and the Quagga Project is trying to recreate the phenotype of hair coat pattern and related characteristics by selectively breeding Burchell's zebras. 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/Quagga, 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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Groenendael (Belgian Shepherd Dog) - Video Learning - WizScience.com
 
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The "Groenendael" is a dog that is included in the Belgian Shepherd breed. In the United States it is generally recognized under the name "Belgian Sheepdog". The Groenendael is recognized by all major kennel clubs. Like all Belgium Shepherd, the Groenendael is a medium-sized, hard-working, square-proportioned breed of dog in the sheepdog family. The Groenendael is recognized by its distinctive black coat. The Groenendael should be athletic, strong, imposing, rustic, and balanced in appearance. It should look natural, never as though it has been prepared just for the show ring. Its coat should be profuse, but never look as though it would inhibit the dog's working ability in any way. The colour is always black, with small white markings being allowed on the chest. When being shown, its handler should never have to force it into position; ideally the handler should not have to touch the dog at all. The Groenendael should be 60 - at the withers for males, and 56 - for females. The weight should be approximately 25 - for males, and 20 - for females. The Groenendael has a thick, double coat. The texture should be hard and dense, never woolly, silky, frizzy, fine, or wiry. The undercoat should be thick and profuse. In conformation shows, dogs without an undercoat are heavily penalized. The Groenendael is intelligent, active, loyal and quietly affectionate. Groenendaels are not a breed for the faint of heart. However for those who have plenty of time, energy, confidence and love, they are wonderful friends. Training and socializing is essential. They are wary of strangers and protective. They love children as long as they are introduced to them at an early age. The Groenendael bonds deeply to its people and cannot live outdoors or in a kennel. It needs to spend time with its family every day and may experience separation anxiety if left alone for long periods of time. 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/Groenendael+(Belgian+Shepherd+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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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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Groundhog - Video Learning - WizScience.com
 
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The "groundhog" , also known as a "woodchuck", or "whistlepig", is a rodent of the family Sciuridae, belonging to the group of large ground squirrels known as marmots. Other marmots, such as the yellow-bellied and hoary marmots, live in rocky and mountainous areas, but the groundhog is a lowland creature. It is widely distributed in North America and common in the northeastern and central United States and Canada. Groundhogs are found as far north as Alaska, with their habitat extending southeast to Georgia. The groundhog is the largest sciurid in its geographical range, typically measuring 40 to long and weighing 2 to. In areas with fewer natural predators and large amounts of alfalfa, groundhogs can grow to 80 cm and 14 kg. Groundhogs are well adapted for digging, with short but powerful limbs and curved, thick claws. Unlike other sciurids, the groundhog's spine is curved, more like that of a mole, and the tail is comparably shorter as well — only about one-fourth of body length. Suited to their temperate habitat, groundhogs are covered with two coats of fur: a dense grey undercoat and a longer coat of banded guard hairs that gives the groundhog its distinctive "frosted" appearance. The etymology of the name "woodchuck" is unrelated to wood or chucking. It stems from an Algonquian name for the animal, "wuchak". The similarity between the words has led to the popular tongue-twister: The groundhog prefers open country and the edges of woodland, and is rarely far from a burrow entrance. Since the clearing of forests provided it with much more suitable habitat, the groundhog population is probably higher now than it was before the arrival of European settlers in North America. Groundhogs are often hunted for sport, which tends to control their numbers. However, their ability to reproduce quickly has tended to mitigate the depopulating effects of sport hunting. As a consequence, the groundhog is a familiar animal to many people in the United States and Canada. 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/Groundhog, 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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Fourth World Conference on Women - Video Learning - WizScience.com
 
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The "Fourth World Conference on Women: Action for Equality, Development and Peace" was the name given for a conference convened by the United Nations 4–15 September 1995 in Beijing, China. The founding United Nations charter included a provision for equality between men and women . Subsequently, from 1945 to 1975 various female officials within the United Nations and leaders of women's movements on the global stage attempted to turn these principles into action. The United Nations General Assembly passed a resolution that 1975 should be International Women's Year. In December 1975, the UN General Assembly passed a further resolution that 1976-1985 should be the "Decade of Women". The first world conference on women was held in Mexico City in 1975. It resulted in the Declaration of Mexico on the Equality of Women and Their Contribution to Development and Peace. The second world conference on women was held in Copenhagen in 1980. The conference agreed that the 1979 Convention on the Elimination of All Forms of Discrimination against Women was an important milestone. The Copenhagen conference also acknowledged the gap between rights being secured for women and women's ability to exercise those rights. It was also agreed that it was action on the three areas of: equal access to education; employment opportunities; and adequate health care services are essential to achieve the goals set out in Mexico. The third world conference on women was held in Nairobi in 1985. The Nairobi conference set out areas by which progress in women's equality could be measured: constitutional and legal measures; equality in social participation; equality in political participation; and decision-making. The conference also acknowledged that women need to participate in all areas of human activity, not just those areas that relate to gender. 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/Fourth+World+Conference+on+Women, 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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Terahertz metamaterials - Video Learning - WizScience.com
 
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""Terahertz metamaterials"" are a new class of composite; artificial materials still under development, which interact at terahertz frequencies. The terahertz frequency range used in materials research is usually defined as 0.1 to 10 THz. See: This bandwidth is also known as the "terahertz gap" because it is noticeably underutilized. This is because terahertz waves are electromagnetic waves with frequencies higher than microwaves but lower than infrared radiation and visible light. These characteristics mean that it is difficult to influence terahertz radiation with conventional electronic components and devices. Electronics technology controls the flow of electrons, and is well developed for microwaves and radio frequencies. Likewise, the terahertz gap also borders optical or photonic wavelengths; the infrared, visible, and ultraviolet ranges , where well developed lens technologies also exist. However, the terahertz wavelength, or frequency range, appears to be useful for security screening, medical imaging, wireless communications systems, non-destructive evaluation, and chemical identification, as well as submillimeter astronomy. Finally, as a non-ionizing radiation it does not have the risks inherent in X-ray screening. Currently, a fundamental lack in naturally occurring materials that allow for the desired electromagnetic response has led to constructing new artificial composite materials, termed metamaterials. The metamaterials are based on a lattice structure which mimics crystal structures. However, the lattice structure of this new material consists of rudimentary elements much larger than atoms or single molecules, but is an artificial, rather than a naturally occurring structure. Yet, the interaction achieved is below the dimensions of the terahertz radiation wave. In addition, the desired results are based on the resonant frequency of fabricated fundamental elements. The appeal and usefulness is derived from a resonant response that can be tailored for specific applications, and can be controlled electrically or optically. Or the response can be as a passive material. 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/Terahertz+metamaterials, 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/Terahertz+metamaterials, 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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433 Eros - Video Learning - WizScience.com
 
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"433 Eros" is an S-type near-Earth asteroid approximately 34.4 * in size, the second-largest near-Earth asteroid after 1036 Ganymed. It was discovered in 1898 and was the first near-Earth asteroid discovered. It was the first asteroid orbited by an Earth probe . It belongs to the Amor group. Eros is a Mars-crosser asteroid, the first known to come within the orbit of Mars. Objects in such an orbit can remain there for only a few hundred million years before the orbit is perturbed by gravitational interactions. Dynamical integrations suggest that Eros may evolve into an Earth-crosser within as short an interval as two million years, and has a roughly 50% chance of doing so over a time scale of 10 8 –10 9 years. It is a potential Earth impactor, comparable in size to the impactor that created Chicxulub crater and led to the extinction of the dinosaurs. The NEAR Shoemaker probe visited Eros twice, first with a 1998 flyby, and then by orbiting it in 2000 when it extensively photographed its surface. On February 12, 2001, at the end of its mission, it landed on the asteroid's surface using its maneuvering jets. Eros is named after the Greek god of love, Erōs. It is pronounced or sometimes . The rarely used adjectival form of the name is "Erotian" . Surface gravity depends on the distance from a spot on the surface to the center of a body's mass. The Erotian surface gravity varies greatly, since Eros is not a sphere but an elongated peanut-shaped object. The daytime temperature on Eros can reach about 100 °C at perihelion. Nighttime measurements fall near −150 °C. Eros's density is 2.67 g/cm 3 , about the same as the density of Earth's crust. It rotates once every 5.27 hours. 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/433+Eros, 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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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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Nonius horse - Video Learning - WizScience.com
 
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The "Nonius" is a Hungarian horse breed named after its Anglo-Norman foundation sire. Generally dark in color, it is a muscular and heavy-boned breed, similar in type to other light draft and driving horses. The breed was developed at the Imperial Stud at Mezőhegyes, Hungary by careful linebreeding. Originally bred to serve as a light draft and utility horse for Hungary's military, the breed became a useful agricultural horse during the 20th century. The depredations of World War II significantly reduced the Nonius' population, and in the decades after the war, a downturn in the usage of horses in Hungary sent many members of the breed to slaughter. Today the breed is bred by preservationists and is used in agriculture, leisure riding, and competitive driving sports. The largest numbers of Nonius horses are still found at Mezőhegyes, with representatives in other eastern European nations as well. Close linebreeding during the breed's establishment and continued use of a closed studbook have contributed to a recognizable and reliably-transmitted type in the Nonius. The vast majority are black, dark bay or brown, either unmarked or modestly marked with white. Bay individuals are more common among the Nonius horses from Hortobágy National Park. The breed is also known for the heavy but proportional head with a convex profile called either a "ram's head" or "Roman nose". The breed exhibits traits common to heavy-boned driving and light draft horses: powerful and arched high-set neck, broad and muscular back, open but powerful loin, deep and sloping hindquarters. The chest is broad rather than deep, and is usually more shallow than the hindquarters. The hooves and joints are large and the legs are dry. Nonius horses stand between 155 to. One of the heaviest warmblood driving horses, the ideal Nonius has a girth measurement of 180 - and a cannon circumference of 22 -. Nonius horses are also known for a kind, even temperament and great willingness and capacity for work both in harness and under saddle. In addition they are usually easy keepers with high endurance. 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/Nonius+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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