Portal:Science

Hassium is a synthetic chemical element; it has symbol Hs and atomic number 108. Hassium is highly radioactive: its most stable known isotopes have half-lives of approximately ten seconds. One of its isotopes, ²⁷⁰Hs, has magic numbers of protons and neutrons for deformed nuclei, giving it greater stability against spontaneous fission. Hassium is a superheavy element; it has been produced in a laboratory in very small quantities by fusing heavy nuclei with lighter ones. Natural occurrences of the element have been hypothesised but never found. (Full article...)

The Aylesbury duck is a breed of domesticated duck, bred mainly for its meat and appearance. It is a large duck with pure white plumage, a pink bill, orange legs and feet, an unusually large keel, and a horizontal stance with its body parallel to the ground. The precise origins of the breed are unclear, but raising white ducks became popular in Aylesbury, Buckinghamshire, England, in the 18th century owing to the demand for white feathers as a filler for quilts. Over the 19th century selective breeding for size, shape and colour led to the Aylesbury duck. (Full article...)

The Lesser Antillean macaw or Guadeloupe macaw (Ara guadeloupensis) is a hypothetical extinct species of macaw that is thought to have been endemic to the Lesser Antillean island region of Guadeloupe. In spite of the absence of conserved specimens, many details about the Lesser Antillean macaw are known from several contemporary accounts, and the bird is the subject of some illustrations. Austin Hobart Clark described the species on the basis of these accounts in 1905. Due to the lack of physical remains, and the possibility that sightings were of macaws from the South American mainland, doubts have been raised about the existence of this species. A phalanx bone from the island of Marie-Galante confirmed the existence of a similar-sized macaw inhabiting the region prior to the arrival of humans and was correlated with the Lesser Antillean macaw in 2015. Later that year, historical sources distinguishing between the red macaws of Guadeloupe and the scarlet macaw (A. macao) of the mainland were identified, further supporting its validity. (Full article...)

Limusaurus is a genus of theropod dinosaur that lived in what is now China during the Late Jurassic, around 161 to 157 million years ago. The type and only species Limusaurus inextricabilis was described in 2009 from specimens found in the Upper Shishugou Formation in the Junggar Basin of China. The genus name consists of the Latin words for "mud" and "lizard", and the species name means "impossible to extricate", both referring to these specimens possibly dying after being mired. Limusaurus was a small, slender animal, about 1.7 m (5 ft 7 in) in length and 15 kg (33 lb) in weight, which had a long neck and legs but very small forelimbs (with reduced first and fourth fingers). It underwent a drastic morphological transformation as it aged: while juveniles were toothed, these teeth were completely lost and replaced by a beak with age. Several of these features were convergently similar to the later ornithomimid theropods as well as the earlier non-dinosaurian shuvosaurids. (Full article...)

Verpa bohemica is a species of fungus in the family Morchellaceae. The synonym Ptychoverpa bohemica is often used by European mycologists and it is commonly known as the early morel or the wrinkled thimble-cap. The mushroom has a pale yellow or brown thimble-shaped cap—2 to 4 cm (3⁄4 to 1+5⁄8 in) in diameter by 2 to 5 cm (3⁄4 to 2 in) long—that has a surface wrinkled and ribbed with brain-like convolutions. A feature distinguishing the species from true morels (genus Morchella), the cap hangs free from the top of the stem, which is lighter in color, brittle, and up to 12 cm (4+3⁄4 in) long by 1 to 2.5 cm (3⁄8 to 1 in) thick. Microscopically, the mushroom is distinguished by its large spores, typically 60–80 by 15–18 μm, and the presence of only two spores per ascus. (Full article...)

Agaricus deserticola, commonly known as the gasteroid agaricus, is a species of fungus in the family Agaricaceae. Found only in southwestern and western North America, A. deserticola is adapted for growth in dry or semi-arid habitats. The fruit bodies are secotioid, meaning the spores are not forcibly discharged, and the cap does not fully expand. Unlike other Agaricus species, A. deserticola does not develop true gills, but rather a convoluted and networked system of spore-producing tissue called a gleba. When the partial veil breaks or pulls away from the stem or the cap splits radially, the blackish-brown gleba is exposed, which allows the spores to be dispersed. (Full article...)

Apollo 16 (April 16–27, 1972) was the tenth crewed mission in the United States Apollo space program, administered by NASA, and the fifth and penultimate to land on the Moon. It was the second of Apollo's "J missions", with an extended stay on the lunar surface, a focus on science, and the use of the Lunar Roving Vehicle (LRV). The landing and exploration were in the Descartes Highlands, a site chosen because some scientists expected it to be an area formed by volcanic action, though this proved not to be the case. (Full article...)

The thylacine (/ˈθaɪləsiːn/; binomial name Thylacinus cynocephalus), also commonly known as the Tasmanian tiger or Tasmanian wolf, is an extinct carnivorous marsupial that was native to the Australian mainland and the islands of Tasmania and New Guinea. The thylacine died out in New Guinea and mainland Australia around 3,600–3,200 years ago, prior to the arrival of Europeans, possibly because of the introduction of the dingo, whose earliest record dates to around the same time, but which never reached Tasmania. Prior to European settlement, around 5,000 remained in the wild on Tasmania. Beginning in the nineteenth century, they were perceived as a threat to the livestock of farmers and bounty hunting was introduced. The last known of its species died in 1936 at Hobart Zoo in Tasmania. The thylacine is widespread in popular culture and is a cultural icon in Australia. (Full article...)

The camas pocket gopher (Thomomys bulbivorus), also known as the camas rat or Willamette Valley gopher, is a rodent, the largest member in the genus Thomomys, of the family Geomyidae. First described in, it is endemic to the Willamette Valley of northwestern Oregon in the United States. The herbivorous gopher forages for vegetable and plant matter, which it collects in large, fur-lined, external cheek pouches. Surplus food is hoarded in an extensive system of tunnels. The dull-brown-to-lead-gray coat changes color and texture over the year. The mammal's characteristically large, protuberant incisors are well adapted for use in tunnel construction, particularly in the hard clay soils of the Willamette Valley. The gophers make chattering sounds with their teeth; males and females make purring (or crooning) sounds when they are together, and the young make twittering sounds. Born toothless, blind and hairless, the young grow rapidly before being weaned at about six weeks of age. (Full article...)

Netley Abbey is a ruined late medieval monastery in the village of Netley near Southampton in Hampshire, England. The abbey was founded in 1239 as a house for monks of the austere Cistercian order. Despite royal patronage, Netley was never rich, produced no influential scholars nor churchmen, and its nearly 300-year history was quiet. The monks were best known to their neighbours for the generous hospitality they offered to travellers on land and sea. (Full article...)

Cucurbita (Latin for 'gourd') is a genus of herbaceous fruits in the gourd family, Cucurbitaceae (also known as cucurbits or cucurbi), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash, pumpkin, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus Lagenaria, which is in the same family and subfamily as Cucurbita, but in a different tribe. These other gourds are used as utensils or vessels, and their young fruits are eaten much like those of the Cucurbita species. (Full article...)

Europa /jʊˈroʊpə/ , or Jupiter II, is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet of all the 95 known moons of Jupiter. It is also the sixth-largest moon in the Solar System. Europa was discovered independently by Simon Marius and Galileo Galilei and was named (by Marius) after Europa, the Phoenician mother of King Minos of Crete and lover of Zeus (the Greek equivalent of the Roman god Jupiter). (Full article...)

The oceanic whitetip shark (Carcharhinus longimanus) is a large pelagic requiem shark inhabiting tropical and warm temperate seas. It has a stocky body with long, white-tipped, rounded fins. The species is typically solitary, though they may gather in large numbers at food concentrations. Bony fish and cephalopods are the main components of its diet and females give live birth. (Full article...)

The bog turtle (Glyptemys muhlenbergii) is a critically endangered species of semiaquatic turtle in the family Emydidae. The species is endemic to the eastern United States. It was first scientifically described in 1801 after an 18th-century survey of Pennsylvania. The smallest North American turtle, its carapace measures about 10 centimeters (4 in) long when fully grown. Although the bog turtle is similar in appearance to the painted or spotted turtles, its closest relative is actually the somewhat larger wood turtle. The bog turtle can be found from Vermont in the north, south to Georgia, and west to Ohio. Diurnal and secretive, it spends most of its time buried in mud and – during the winter months – in hibernation. The bog turtle is omnivorous, feeding mainly on small invertebrates. The bog turtle is the state reptile of New Jersey. (Full article...)

Auriscalpium vulgare, commonly known as the pinecone mushroom, the cone tooth, or the ear-pick fungus, is a species of fungus in the family Auriscalpiaceae of the order Russulales. It was first described in 1753 by Carl Linnaeus, who included it as a member of the tooth fungi genus Hydnum, but British mycologist Samuel Frederick Gray recognized its uniqueness and in 1821 transferred it to the genus Auriscalpium that he created to contain it. The fungus is widely distributed in Europe, Central America, North America, and temperate Asia. Although common, its small size and nondescript colors lead it to be easily overlooked in the pine woods where it grows. A. vulgare is not generally considered edible because of its tough texture, but some historical literature says it used to be consumed in France and Italy. (Full article...)

Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its global ocean, covering 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere. Most of Earth's land is somewhat humid and covered by vegetation, while large sheets of ice at Earth's polar deserts retain more water than Earth's groundwater, lakes, rivers and atmospheric water combined. Earth's crust consists of slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth has a liquid outer core that generates a magnetosphere capable of deflecting most of the destructive solar winds and cosmic radiation. (Full article...)

Artificial intelligence (AI), in its broadest sense, is intelligence exhibited by machines, particularly computer systems. It is a field of research in computer science that develops and studies methods and software that enable machines to perceive their environment and uses learning and intelligence to take actions that maximize their chances of achieving defined goals. Such machines may be called AIs. (Full article...)

Google Scholar is a freely accessible web search engine that indexes the full text or metadata of scholarly literature across an array of publishing formats and disciplines. Released in beta in November 2004, the Google Scholar index includes peer-reviewed online academic journals and books, conference papers, theses and dissertations, preprints, abstracts, technical reports, and other scholarly literature, including court opinions and patents. (Full article...)

In statistics, the standard deviation is a measure of the amount of variation of a random variable expected about its mean. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range. The standard deviation is commonly used in the determination of what constitutes an outlier and what does not. (Full article...)

Science is a rigorous, systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the world. Modern science is typically divided into three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; the social sciences (e.g., economics, psychology, and sociology), which study individuals and societies; and the formal sciences (e.g., logic, mathematics, and theoretical computer science), which study formal systems, governed by axioms and rules. There is disagreement whether the formal sciences are science disciplines, as they do not rely on empirical evidence. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as in engineering and medicine. (Full article...)

Ejaculation is the discharge of semen (the ejaculate; normally containing sperm) from the male reproductive tract. It is normally linked with orgasm, which involves involuntary contractions of the pelvic floor. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. Ejaculation can occur spontaneously during sleep, and is a normal part of human sexual development (a nocturnal emission or "wet dream"). In rare cases, ejaculation occurs because of prostatic disease. Anejaculation is the condition of being unable to ejaculate. Ejaculation is normally intensely pleasurable for men; dysejaculation is an ejaculation that is painful or uncomfortable. Retrograde ejaculation is the backward flow of semen into the bladder rather than out of the urethra. (Full article...)

Sci-Hub is a shadow library website that provides free access to millions of research papers, regardless of copyright, by bypassing publishers' paywalls in various ways. Unlike Library Genesis, it does not provide access to books. Sci-Hub was founded in Kazakhstan by Alexandra Elbakyan in 2011, in response to the high cost of research papers behind paywalls (see Serials crisis). The site is extensively used worldwide. In September 2019, the site's operator(s) said that it served approximately 400,000 requests per day.
In addition to its intensive use, Sci-Hub stands out among other shadow libraries because of its easy use/reliability and because of the enormous size of its collection; a 2018 study estimated that Sci-Hub provided access to 95% of all scholarly publications with issued DOI numbers, and on 15 July 2022, Sci-Hub reported that its collection comprised 88,343,822 files. (Full article...)

The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a significant role in the development of many areas of modern technology and science. (Full article...)

In biology, taxonomy (from Ancient Greek τάξις (taxis) 'arrangement', and -νομία (-nomia) 'method') is the scientific study of naming, defining (circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain, kingdom, phylum (division is sometimes used in botany in place of phylum), class, order, family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, as he developed a ranked system known as Linnaean taxonomy for categorizing organisms and binomial nomenclature for naming organisms. (Full article...)

Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. It is considered to be an innate tendency of human psychology. Personification is the related attribution of human form and characteristics to abstract concepts such as nations, emotions, and natural forces, such as seasons and weather. Both have ancient roots as storytelling and artistic devices, and most cultures have traditional fables with anthropomorphized animals as characters. People have also routinely attributed human emotions and behavioral traits to wild as well as domesticated animals. (Full article...)