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Topic Review

A wink is a facial expression made by briefly closing one eye. A wink is an informal mode of non-verbal communication usually signaling shared hidden knowledge or intent. However, it is ambiguous by itself and highly dependent upon additional context, without which a wink could become misinterpreted or even nonsensical. For example, in some regions of the world, a wink may be considered rude or offensive. And depending on the relationship of the people involved, a wink could possibly constitute a sexual gesture.

2.9K
07 Oct 2022

Topic Review

King cherry (Cerasus × nudiflora, 왕벚 wangbeoj, 왕벚나무 wangbeojnamu or 왕벚꽃 wangbeojkkoch) is a Korean native cherry tree originated from Jeju Island. It is a distinct species from Japanese native Yoshino cherry. King cherry is a rare plant and listed as an endangered species. As of April 2017, 194 King cherry trees were growing around Mt. Halla in Jeju Island. According to Gen-ichi Koidzumi, King cherry is erroneously believed to be discovered by a French missionary Emile Taquet although what he discovered was a different species. There have been disputes over the origin of king cherry and Yoshino cherry. In 2007, a study conducted on the comparison of king cherry and Yoshino cherry concluded that these trees were categorized as distinct species. However, South Korean media assert that King cherry is the same species as Yoshino cherry. In Korea most of the places for cherry blossom festivals, including Yeouido and Jinhae, are still planted with Japanese Yoshino cherry trees.

2.9K
01 Nov 2022

Topic Review

Lingua Geographica

Geographic tongue, also known by several other terms,[note 1] is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.

2.9K
26 Oct 2022

Biography

Simcha Jacobovici

Simcha Jacobovici (/ˈsɪmxə jəˈkoʊboʊvɪtʃ/, born April 4, 1953, Petah Tikva, Israel) is an Israeli-Canadian film director, producer, freelance journalist, and writer. His parents were from Iași, Romania.[1] Simcha Jacobovici earned a B.A. in Philosophy and Political Science (with honors) from McGill University and an M.A. in International Relations from the University of Toronto. He

2.9K
15 Nov 2022

Topic Review

Triceratops Obtusus

Triceratops (/traɪˈsɛrəˌtɒps/ trahy-ser-uh-tops; lit. three-horned face) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last-known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. The name Triceratops, which literally means 'three-horned face', is derived from the Greek words trí- (τρί-) meaning 'three', kéras (κέρας) meaning 'horn', and ṓps (ὤψ) meaning 'face'. Bearing a large bony frill, three horns on the skull, and a large four-legged body, exhibiting convergent evolution with rhinoceroses and bovines, Triceratops is one of the most recognizable of all dinosaurs and the most well-known ceratopsid. It was also one of the largest, up to 8–9 metres (26–30 ft) long and 5–9 metric tons (5.5–9.9 short tons) in body mass. It shared the landscape with and was most likely preyed upon by Tyrannosaurus, though it is less certain that two adults did battle in the fanciful manner often depicted in museum displays and popular images. The functions of the frills and three distinctive facial horns on its head have long inspired debate. Traditionally, these have been viewed as defensive weapons against predators. More recent interpretations find it probable that these features were primarily used in species identification, courtship, and dominance display, much like the antlers and horns of modern ungulates. Triceratops was traditionally placed within the "short-frilled" ceratopsids, but modern cladistic studies show it to be a member of the Chasmosaurinae which usually have long frills. Two species, T. horridus and T. prorsus, are considered valid today, from the seventeen species that have ever been named. Research published in 2010 concluded that the contemporaneous Torosaurus, a ceratopsid long regarded as a separate genus, represents Triceratops in its mature form. This view has been disputed; further data is needed to settle the debate. Triceratops has been documented by numerous remains collected since the genus was first described in 1889 by American paleontologist Othniel Charles Marsh. Specimens representing life stages from hatchling to adult have been found. As the archetypal ceratopsid, Triceratops is one of the most popular dinosaurs, and has been featured in film, postal stamps, and many other types of media.

2.9K
17 Nov 2022

Topic Review

The wild turkey (Meleagris gallopavo) is an upland ground bird native to North America, one of two extant species of turkey, and the heaviest member of the order Galliformes. It is the ancestor to the domestic turkey, which was originally derived from a southern Mexican subspecies of wild turkey (not the related ocellated turkey). Although native to North America, the turkey probably got its name from the domesticated variety being imported to Britain in ships coming from the Levant via Spain. The British at the time therefore associated the wild turkey with the country Turkey and the name prevails. An alternative theory posits that another bird, a guinea fowl native to Madagascar introduced to England by Turkish merchants, was the original source, and that the term was then transferred to the New World bird by English colonizers with knowledge of the previous species.

2.9K
16 Nov 2022

Biography

Peter C. Doherty

Peter Charles Doherty AC FRS FMedSci (born 15 October 1940)[1] is an Australian immunologist and Nobel laureate.[2] He received the Albert Lasker Award for Basic Medical Research in 1995, the Nobel Prize in Physiology or Medicine jointly with Rolf M. Zinkernagel[3] in 1996 and was named Australian of the Year in 1997.[4] In the Australia Day Honours of 1997, he was named a Companion of the Order

2.9K
08 Dec 2022

Topic Review

Flashbulb Memory

A flashbulb memory is a highly detailed, exceptionally vivid "snapshot" of the moment and circumstances in which a piece of surprising and consequential (or emotionally arousing) news was learned about. The term "flashbulb memory" suggests the surprise, indiscriminate illumination, detail, and brevity of a photograph; however flashbulb memories are only somewhat indiscriminate and are far from complete. Evidence has shown that although people are highly confident in their memories, the details of the memories can be forgotten. Flashbulb memories are one type of autobiographical memory. Some researchers believe that there is reason to distinguish flashbulb memories from other types of autobiographical memory because they rely on elements of personal importance, consequentiality, emotion, and surprise. Others believe that ordinary memories can also be accurate and long-lasting if they are highly distinctive, personally significant, or repeatedly rehearsed. Flashbulb memories have six characteristic features: place, ongoing activity, informant, own affect, other affect, and aftermath. Arguably, the principal determinants of a flashbulb memory are a high level of surprise, a high level of consequentiality, and perhaps emotional arousal.

2.8K
17 Nov 2022

Biography

Claire Wineland

Claire Lucia Wineland (April 10, 1997 – September 2, 2018) was an American activist and author. Through her non-profit organization "Claire's Place Foundation," she supported people with terminal and chronic illnesses, as well as their families.[1][2] She died from a stroke one week after a lung transplant, at the age of 21. Wineland wrote the book Every Breath I Take, Surviving and Thriving

2.8K
22 Nov 2022

Topic Review

Cosmopolitodus Hastalis

Cosmopolitodus hastalis, the broad-tooth mako (other common names include the extinct giant mako and broad-tooth white shark), is an extinct mackerel shark that lived from the Miocene epoch to the Pliocene epoch. Its teeth can reach lengths up to 3.5 in (7.5 cm) and are found worldwide. It is believed to be an ancestor to the great white shark, a fact supported by the transitional species Carcharodon hubbelli, and most likely would have been one of the major predators in its ecosystem; preying upon small whales and other mammals.

2.8K
28 Oct 2022

Topic Review

Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest vertebrate animal family in general with about 3,000 species, of which only 1,270 remain extant, divided into about 370 genera. Cyprinids range from about 12 mm in size to the 3 m giant barb (Catlocarpio siamensis). By genus and species count, the family makes up more than two-thirds of the ostariophysian order Cypriniformes. The family name is derived from the Greek word kyprînos (κυπρῖνος 'carp').

2.8K
26 Oct 2022

Topic Review

Cartorhynchus (meaning "shortened snout") is an extinct genus of early ichthyosauriform marine reptile that lived during the Early Triassic epoch, about 248 million years ago. The genus contains a single species, Cartorhynchus lenticarpus, named in 2014 by Ryosuke Motani and colleagues from a single nearly-complete skeleton found near Chaohu, Anhui Province, China . Along with its close relative Sclerocormus, Cartorhynchus was part of a diversification of marine reptiles that occurred suddenly (over about one million years) during the Spathian substage, soon after the devastating Permian-Triassic extinction event, but they were subsequently driven to extinction by volcanism and sea level changes by the Middle Triassic. Measuring about 40 centimetres (16 in) long, Cartorhynchus was small animal with a lizard-like body and a short torso; it probably swam in an eel-like manner at slow speeds. Its limbs bore extensive cartilage and could bend like flippers, which may have allowed it to walk on land. The most distinctive features of Cartorhynchus were its short, constricted snout, and its multiple rows of molar-like teeth which grew on the inside surface of its jaw bones. These teeth were not discovered until the specimen was subjected to CT scanning. Cartorhynchus likely preyed on hard-shelled invertebrates using suction feeding, although how it exactly used its inward-directed teeth is not yet known. It was one of up to five independent acquisitions of molar-like teeth among ichthyosauriforms.

2.8K
04 Nov 2022

Topic Review

Echoic memory is the sensory memory that registers specific to auditory information (sounds). Once an auditory stimulus is heard, it is stored in memory so that it can be processed and understood. Unlike visual memory, in which our eyes can scan the stimuli over and over, the auditory stimuli cannot be scanned over and over. Since echoic memories are heard once, they are stored for slightly longer periods of time than iconic memories (visual memories). Auditory stimuli are received by the ear one at a time before they can be processed and understood. For instance, hearing the radio is very different from reading a magazine. A person can only hear the radio once at a given time, while the magazine can be read over and over again. It can be said that the echoic memory is like a "holding tank" concept, because a sound is unprocessed (or held back) until the following sound is heard, and only then can it be made meaningful. This particular sensory store is capable of storing large amounts of auditory information that is only retained for a short period of time (3–4 seconds). This echoic sound resonates in the mind and is replayed for this brief amount of time shortly after being heard. Echoic memory encodes only moderately primitive aspects of the stimuli, for example pitch, which specifies localization to the non-association brain regions.

2.8K
21 Oct 2022

Topic Review

Hadrosaurids (from grc ἁδρός (hadrós) 'stout, thick', and σαύρα (saúra) 'lizard'), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which includes genera such as Edmontosaurus and Parasaurolophus, was a common group of herbivores during the Late Cretaceous Period. Hadrosaurids are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had a similar body layout. Hadrosaurs were among the most dominant herbivores during the Late Cretaceous in Asia and North America, and during the close of the Cretaceous several lineages dispersed into Europe, Africa, South America and Antarctica. Like other ornithischians, hadrosaurids had a predentary bone and a pubic bone which was positioned backwards in the pelvis. Unlike more primitive iguanodonts, the teeth of hadrosaurids are stacked into complex structures known as dental batteries, which acted as effective grinding surfaces. Hadrosauridae is divided into two principal subfamilies: the lambeosaurines (Lambeosaurinae), which had hollow cranial crests or tubes; and the saurolophines (Saurolophinae), identified as hadrosaurines (Hadrosaurinae) in most pre-2010 works, which lacked hollow cranial crests (solid crests were present in some forms). Saurolophines tended to be bulkier than lambeosaurines. Lambeosaurines included the aralosaurins, tsintaosaurins, lambeosaurins and parasaurolophins, while saurolophines included the brachylophosaurins, kritosaurins, saurolophins and edmontosaurins. Hadrosaurids were facultative bipeds, with the young of some species walking mostly on two legs and the adults walking mostly on four.

2.8K
02 Dec 2022

Topic Review

Hyraxes (from grc ὕραξ (Script error: No such module "Ancient Greek".) 'shrewmouse'), also called dassies, are small, thickset, herbivorous mammals in the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Typically, they measure between 30 and 70 cm (12 and 28 in) long and weigh between 2 and 5 kg (4 and 11 lb). They are superficially similar to pikas and marmots, but are more closely related to elephants and sea cows. Hyraxes have a life span from 9 to 14 years. Five extant species are recognised: the rock hyrax (Procavia capensis) and the yellow-spotted rock hyrax (Heterohyrax brucei), which both live on rock outcrops, including cliffs in Ethiopia and isolated granite outcrops called koppies in southern Africa; the western tree hyrax (Dendrohyrax dorsalis), southern tree hyrax (D. arboreus), and eastern tree hyrax (D. validus). Their distribution is limited to Africa, except for P. capensis, which is also found in the Middle East.

2.8K
20 Oct 2022

Topic Review

The subphylum Chelicerata (from New Latin, from fr chélicère, from grc χηλή (Script error: No such module "Ancient Greek".) 'claw, chela', and κέρας (Script error: No such module "Ancient Greek".) 'horn') constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including harvestmen, scorpions, spiders, solifuges, ticks, and mites, among many others), as well as a number of extinct lineages, such as the eurypterids (sea scorpions) and chasmataspidids. The Chelicerata originated as marine animals in the Middle Cambrian period; the first confirmed chelicerate fossils, belonging to Sanctacaris, date from 508 million years ago. The surviving marine species include the four species of xiphosurans (horseshoe crabs), and possibly the 1,300 species of pycnogonids (sea spiders), if the latter are indeed chelicerates. On the other hand, there are over 77,000 well-identified species of air-breathing chelicerates, and there may be about 500,000 unidentified species. Like all arthropods, chelicerates have segmented bodies with jointed limbs, all covered in a cuticle made of chitin and proteins. The chelicerate body plan consists of two tagmata, the prosoma and the opisthosoma, except that mites have lost a visible division between these sections. The chelicerae, which give the group its name, are the only appendages that appear before the mouth. In most sub-groups, they are modest pincers used to feed. However, spiders' chelicerae form fangs that most species use to inject venom into prey. The group has the open circulatory system typical of arthropods, in which a tube-like heart pumps blood through the hemocoel, which is the major body cavity. Marine chelicerates have gills, while the air-breathing forms generally have both book lungs and tracheae. In general, the ganglia of living chelicerates' central nervous systems fuse into large masses in the cephalothorax, but there are wide variations and this fusion is very limited in the Mesothelae, which are regarded as the oldest and most basal group of spiders. Most chelicerates rely on modified bristles for touch and for information about vibrations, air currents, and chemical changes in their environment. The most active hunting spiders also have very acute eyesight. Chelicerates were originally predators, but the group has diversified to use all the major feeding strategies: predation, parasitism, herbivory, scavenging and eating decaying organic matter. Although harvestmen can digest solid food, the guts of most modern chelicerates are too narrow for this, and they generally liquidize their food by grinding it with their chelicerae and pedipalps and flooding it with digestive enzymes. To conserve water, air-breathing chelicerates excrete waste as solids that are removed from their blood by Malpighian tubules, structures that also evolved independently in insects. While the marine horseshoe crabs rely on external fertilization, air-breathing chelicerates use internal but usually indirect fertilization. Many species use elaborate courtship rituals to attract mates. Most lay eggs that hatch as what look like miniature adults, but all scorpions and a few species of mites keep the eggs inside their bodies until the young emerge. In most chelicerate species the young have to fend for themselves, but in scorpions and some species of spider the females protect and feed their young. The evolutionary origins of chelicerates from the early arthropods have been debated for decades. Although there is considerable agreement about the relationships between most chelicerate sub-groups, the inclusion of the Pycnogonida in this taxon has recently been questioned (see below), and the exact position of scorpions is still controversial, though they were long considered the most basal of the arachnids. Venom has evolved three times in the chelicerates; spiders, scorpions and pseudoscorpions, or four times if the hematophagous secretions produced by ticks are included. In addition there have been undocumented descriptions of venom glands in Solifugae. Chemical defense has been found in whip scorpions, shorttailed whipscorpions, harvestmen, beetle mites and sea spiders. Although the venom of a few spider and scorpion species can be very dangerous to humans, medical researchers are investigating the use of these venoms for the treatment of disorders ranging from cancer to erectile dysfunction. The medical industry also uses the blood of horseshoe crabs as a test for the presence of contaminant bacteria. Mites can cause allergies in humans, transmit several diseases to humans and their livestock, and are serious agricultural pests.

2.8K
18 Oct 2022

Topic Review

List of Fictional Crocodiles and Alligators

This is a list of fictional crocodiles and alligators from literature, folklore and myth, mascots and emblems of teams and organizations, comics, films, animations and video games. This list is subsidiary to the list of fictional animals. It is restricted to notable crocodilian characters from notable works of fiction. Characters that appear in multiple media may have separate listings for each appearance, while in instances where a character has appeared in several separate works in a single medium, only the earliest will be recorded here.

2.8K
21 Oct 2022

Biography

Arthur Eddington

Sir Arthur Stanley Eddington OM FRS[1] (28 December 1882 – 22 November 1944) was an English astronomer, physicist, and mathematician. He was also a philosopher of science and a populariser of science. The Eddington limit, the natural limit to the luminosity of stars, or the radiation generated by accretion onto a compact object, is named in his honour. Around 1920, he anticipated the discover

2.8K
14 Nov 2022

Topic Review

Encoding (Memory)

Memory has the ability to encode, store and recall information. Memories give an organism the capability to learn and adapt from previous experiences as well as build relationships. Encoding allows a perceived item of use or interest to be converted into a construct that can be stored within the brain and recalled later from long-term memory. Working memory stores information for immediate use or manipulation which is aided through hooking onto previously archived items already present in the long-term memory of an individual.

2.8K
17 Nov 2022

Topic Review

Nap pods also known as sleep pods, napping pods or nap capsules are special types of structures or chairs, often used in corporate/ workplace environments, hospitals and universities, that allow people to nap. Users use the pods to take private sleep breaks, often aided by technology and ambient features. Nap pods have emerged in corporate environments, hospitals, universities, airports and other public places. Their supposed efficacy is rooted in research that suggests that 20-minute naps could reduce signs of fatigue, boost energy levels, improve focus, boost productivity, improve mood, enhance learning, reduce stress and reduce the risk of cardiovascular disease.

2.8K
04 Nov 2022

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