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Научный портал
Наука (от латинского слова scientia , что означает «знание») - это систематическое предприятие, которое создает и систематизирует знания в форме проверяемых объяснений и предсказаний о Вселенной .
Самые ранние корни науки можно проследить до Древнего Египта и Месопотамии примерно с 3000 по 1200 год до нашей эры. Их вклад в математику , астрономию и медицины вошли и в форме греческой натурфилософии в классической древности , в результате чего было сделаны формальные попытки дать объяснение событий в физическом мире на основе естественных причин. После падения Западной Римской империи знания греческих концепций мира ухудшились в Западной Европе в первые века (с 400 по 1000 год н.э.) Средневековья., но сохранился в мусульманском мире во время Золотого века ислама . Восстановление и ассимиляция греческих работ и исламских исследований в Западной Европе с 10 по 13 век возродили « натурфилософию », которая позже была преобразована Научной революцией , начавшейся в 16 веке, когда новые идеи и открытия отошли от прежних греческих концепций и традиции. Научный метод вскоре сыграл большую роль в создании знаний и он не был до 19 - го века , что многие институциональные и профессиональныеначали складываться особенности науки; вместе с заменой «натурфилософии» на «естествознание».
Современная наука обычно делится на три основные отрасли, которые состоят из естественных наук (например, биологии , химии и физики ), изучающих природу в самом широком смысле; в социальных науках (например, экономика , психология и социология ), что изучение отдельных лиц и общества; и формальные науки (например, логика , математика и теоретическая информатика), которые изучают абстрактные понятия. Однако существуют разногласия относительно того, действительно ли формальные науки представляют собой науку, поскольку они не полагаются на эмпирические данные . Дисциплины, использующие существующие научные знания для практических целей, такие как инженерия и медицина, называются прикладными науками .
Наука основана на исследованиях , которые обычно проводятся учеными, работающими в академических и исследовательских учреждениях , государственных учреждениях и компаниях . Практическое влияние научных исследований привело к появлению научных политик, которые стремятся повлиять на научное предприятие, отдавая приоритет развитию коммерческой продукции , вооружений , здравоохранения , общественной инфраструктуры и защиты окружающей среды . ( Полная статья ... )
Выбранная статья
- Реконструированный скелет, Геологический музей Хэнань
Nemegtomaia являетсяродомизовирапторовидного динозавраизчто в настоящем времяМонголиякоторый жил впозднем меловом периоде, около 70 миллионов лет назад. Первый экземпляр был обнаружен в 1996 году и стал основой нового рода и вида N. barsboldi в 2004 году. Первоначальное название рода былоNemegtia, нов 2005 годуоно было изменено наNemegtomaia, поскольку прежнее название былозанято. Первая часть общего названия относится кбассейну Немегт., где было найдено животное, а вторая часть означает «хорошая мать», имея в виду тот факт, что овирапториды, как известно, вынашивали яйца. В название конкретных почестей палеонтолог Ринчена Barsbold . Еще два экземпляра были найдены в 2007 году, один из которых был найден на вершине гнезда с яйцами, но динозавр получил название своего рода до того, как его обнаружили связанным с яйцами.
Немегтомайя, по оценкам, имела длину около 2 м (7 футов) и весила 40 кг (85 фунтов). Как овирапторозавр , он был бы пернатым. У него был глубокий, узкий и короткий череп с изогнутым гребнем. Он был беззубым, имел короткую мордочку с попугаем-подобный клюв и пара зубчатых выступов на нёбе . У него было три пальца; первый был самым большим и нес сильную лапу. Nemegtomaia классифицируется как член подсемейства овирапторид Heyuanninae и является единственным известным членом этой группы с черепным гребнем. Хотя Nemegtomaia был использован предположить , что oviraptorosaurs были нелетающие птицы , то клады , как правило , рассматривается как группа , не являющихся птиц динозавров. ( Полная статья ... )
Cyathus is a genus of fungi in the Nidulariaceae, a family collectively known as the bird's nest fungi. They are given this name since they resemble tiny bird's nests filled with "eggs", structures large enough to have been mistaken in the past for seeds. However, these are now known to be reproductive structures containing spores. The "eggs", or peridioles, are firmly attached to the inner surface of this fruit body by an elastic cord of mycelia known as a funiculus. The 45 species are widely distributed throughout the world and some are found in most countries, although a few exist in only one or two locales. Cyathus stercoreus is considered endangered in a number of European countries. Species of Cyathus are also known as splash cups, which refers to the fact that falling raindrops can knock the peridioles out of the open-cup fruit body. The internal and external surfaces of this cup may be ridged longitudinally (referred to as plicate or striate); this is one example of a taxonomic characteristic that has traditionally served to distinguish between species.
Generally considered inedible, Cyathus species are saprobic, since they obtain nutrients from decomposing organic matter. They usually grow on decaying wood or woody debris, on cow and horse dung, or directly on humus-rich soil. The life cycle of this genus allows it to reproduce both sexually, with meiosis, and asexually via spores. Several Cyathus species produce bioactive compounds, some with medicinal properties, and several lignin-degrading enzymes from the genus may be useful in bioremediation and agriculture. Phylogenetic analysis is providing new insights into the evolutionary relationships between the various species in Cyathus, and has cast doubt on the validity of the older classification systems that are based on traditional taxonomic characteristics (Full article...)
Calvatia sculpta, commonly known as the sculpted puffball, the sculptured puffball, the pyramid puffball, and the Sierran puffball, is a species of puffball fungus in the family Agaricaceae. Attaining dimensions of up to 8 to 15 cm (3.1 to 5.9 in) tall by 8 to 10 cm (3.1 to 3.9 in) wide, the pear- or egg-shaped puffball is readily recognizable because of the large pyramidal or polygonal warts covering its surface. It is edible when young, before the spores inside the fruit body disintegrate into a brownish powder. The spores are roughly spherical, and have wart-like projections on their surfaces.
Originally described from the Sierra Nevada, C. sculpta is found in mountainous areas in western North America, and was found in a Brazilian dune in 2008. It may be easily confused with Calbovista subsculpta, a similar puffball that—in addition to differences observable only with a microscope—is larger, and has slightly raised warts with a felt-like texture. Other similar species include Calvatia arctica and immature specimens of Amanita magniverrucata. (Full article...)- Detail of a 1770 map of North Carolina by John Collett depicting the locations of Fort Dobbs, the Yadkin and Catawba Rivers, and Salisbury.
Fort Dobbs was an 18th-century fort in the Yadkin–Pee Dee River Basin region of the Province of North Carolina, near what is now Statesville in Iredell County. Used for frontier defense during and after the French and Indian War, the fort was built to protect the American settlers of the western portion of what was then Rowan County, and served as a vital outpost for soldiers, traders, and colonial officials. Fort Dobbs' primary structure was a blockhouse with log walls, surrounded by a shallow ditch, and by 1761, a palisade. It was intended to provide protection from French-allied Native Americans such as the Shawnee and Delaware, and French raids into North Carolina.
The fort's name honored Arthur Dobbs, the Royal Governor of North Carolina from 1755 to 1765, who played a role in designing the fort and authorized its construction. Between 1756 and 1761, the fort was garrisoned by a variable number of soldiers, many of whom were sent to fight in Pennsylvania and the Ohio River Valley during the French and Indian War. On February 27, 1760, the fort was the site of an engagement between Cherokee warriors and Provincial soldiers that ended in a victory for the Provincials. After this battle and other attacks by Cherokee warriors on North Carolinan settlements, several successful counter-attacks were inflicted by the Provincials against the Cherokee, largely quelling their incursions. (Full article...) - An assortment of millipedes (not to scale)
Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name being derived from this feature. Each double-legged segment is a result of two single segments fused together. Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a ball. Although the name "millipede" derives from the Latin for "thousand feet", no known species has 1,000; the record of 750 legs belongs to Illacme plenipes. There are approximately 12,000 named species classified into 16 orders and around 140 families, making Diplopoda the largest class of myriapods, an arthropod group which also includes centipedes and other multi-legged creatures.
Most millipedes are slow-moving detritivores, eating decaying leaves and other dead plant matter. Some eat fungi or suck plant fluids, and a small minority are predatory. Millipedes are generally harmless to humans, although some can become household or garden pests. Millipedes can be unwanted especially in greenhouses where they can cause severe damage to emergent seedlings. Most millipedes defend themselves with a variety of chemicals secreted from pores along the body, although the tiny bristle millipedes are covered with tufts of detachable bristles. Its primary defence mechanism is to curl into a tight coil, thereby protecting its legs and other vital delicate areas on the body behind a hard exoskeleton. Reproduction in most species is carried out by modified male legs called gonopods, which transfer packets of sperm to females. (Full article...) - Cardellina rubra melanauris
Sinaloa, Mexico
The red warbler (Cardellina rubra) is a small passerine bird of the New World warbler family Parulidae endemic to the highlands of Mexico, north of the Isthmus of Tehuantepec. It is closely related to, and forms a superspecies with, the pink-headed warbler of southern Mexico and Guatemala. There are three subspecies, found in disjunct populations, which differ primarily in the color of their ear patch and in the brightness and tone of their body plumage. The adult is bright red, with a white or gray ear patch, depending on the subspecies; young birds are pinkish-brown, with a whitish ear patch and two pale wingbars.
Breeding typically occurs between February and May. The female lays three or four eggs in a domed nest, which she builds on the ground. Though she alone incubates the eggs, both sexes feed the young and remove fecal sacs from the nest. The young fledge within 10–11 days of hatching. The red warbler is an insectivore, gleaning primarily in understory shrubs. Although this bird is considered to be a least-concern species according to the International Union for Conservation of Nature (IUCN), its numbers are thought to be declining due to habitat destruction. (Full article...) - Pigeon with German miniature camera, probably during the First World War
Pigeon photography is an aerial photography technique invented in 1907 by the German apothecary Julius Neubronner, who also used pigeons to deliver medications. A homing pigeon was fitted with an aluminium breast harness to which a lightweight time-delayed miniature camera could be attached. Neubronner's German patent application was initially rejected, but was granted in December 1908 after he produced authenticated photographs taken by his pigeons. He publicized the technique at the 1909 Dresden International Photographic Exhibition, and sold some images as postcards at the Frankfurt International Aviation Exhibition and at the 1910 and 1911 Paris Air Shows.
Initially, the military potential of pigeon photography for aerial reconnaissance appeared interesting. Battlefield tests in World War I provided encouraging results, but the ancillary technology of mobile dovecotes for messenger pigeons had the greatest impact. Owing to the rapid perfection of aviation during the war, military interest in pigeon photography faded and Neubronner abandoned his experiments. The idea was briefly resurrected in the 1930s by a Swiss clockmaker, and reportedly also by the German and French militaries. Although war pigeons were deployed extensively during World War II, it is unclear to what extent, if any, birds were involved in aerial reconnaissance. The United States Central Intelligence Agency (CIA) later developed a battery-powered camera designed for espionage pigeon photography; details of its use remain classified. (Full article...) - Thyrotoxic periodic paralysis occurs when the thyroid gland releases excessive amounts of thyroxine (thyroid hormone).
Thyrotoxic periodic paralysis (TPP) is a condition featuring attacks of muscle weakness in the presence of hyperthyroidism (overactivity of the thyroid gland). Hypokalemia (a decreased potassium level in the blood) is usually present during attacks. The condition may be life-threatening if weakness of the breathing muscles leads to respiratory failure, or if the low potassium levels lead to cardiac arrhythmias (irregularities in the heart rate). If untreated, it is typically recurrent in nature.
The condition has been linked with genetic mutations in genes that code for certain ion channels that transport electrolytes (sodium and potassium) across cell membranes. The main ones are the L-type calcium channel α1-subunit and potassium inward rectifier 2.6; it is therefore classified as a channelopathy. The abnormality in the channel is thought to lead to shifts of potassium into cells, under conditions of high thyroxine (thyroid hormone) levels, usually with an additional precipitant. (Full article...) - Roald Amundsen, Helmer Hanssen, Sverre Hassel and Oscar Wisting (l–r) at "Polheim", the tent erected at the South Pole on 16 December 1911. The top flag is the Flag of Norway; the bottom is marked "Fram". Photograph by Olav Bjaaland.
The first expedition to reach the geographic South Pole was led by the Norwegian explorer Roald Amundsen. He and four others arrived at the pole on 14 December 1911, five weeks ahead of a British party led by Robert Falcon Scott as part of the Terra Nova Expedition. Amundsen and his team returned safely to their base, and later heard that Scott and his four companions had died on their return journey.
Amundsen's initial plans had focused on the Arctic and the conquest of the North Pole by means of an extended drift in an icebound ship. He obtained the use of Fridtjof Nansen's polar exploration ship Fram, and undertook extensive fundraising. Preparations for this expedition were disrupted when, in 1909, the rival American explorers Frederick Cook and Robert E. Peary each claimed to have reached the North Pole. Amundsen then changed his plan and began to prepare for a conquest of the South Pole; uncertain of the extent to which the public and his backers would support him, he kept this revised objective secret. When he set out in June 1910, he led even his crew to believe they were embarking on an Arctic drift, and revealed their true Antarctic destination only when Fram was leaving their last port of call, Madeira. (Full article...) - Sumatran rhinoceros at Sumatran Rhino Sanctuary in Lampung, Indonesia
The Sumatran rhinoceros, also known as the hairy rhinoceros or Asian two-horned rhinoceros (Dicerorhinus sumatrensis), is a rare member of the family Rhinocerotidae and one of five extant species of rhinoceros. It is the only extant species of the genus Dicerorhinus. It is the smallest rhinoceros, although it is still a large mammal; it stands 112–145 cm (3.67–4.76 ft) high at the shoulder, with a head-and-body length of 2.36–3.18 m (7.7–10.4 ft) and a tail of 35–70 cm (14–28 in). The weight is reported to range from 500 to 1,000 kg (1,100 to 2,200 lb), averaging 700–800 kg (1,540–1,760 lb), although there is a single record of a 2,000 kg (4,410 lb) specimen. Like both African species, it has two horns; the larger is the nasal horn, typically 15–25 cm (5.9–9.8 in), while the other horn is typically a stub. A coat of reddish-brown hair covers most of the Sumatran rhino's body.
Members of the species once inhabited rainforests, swamps, and cloud forests in India, Bhutan, Bangladesh, Myanmar, Laos, Thailand, Malaysia, Indonesia, and China. In historical times, they lived in southwest China, particularly in Sichuan. They are now critically endangered, with only five substantial populations in the wild: four in Sumatra and one in Borneo. Their numbers are difficult to determine because they are solitary animals that are widely scattered across their range, but they are estimated to number fewer than 80. The species was completely extirpated from Malaysia in 2019, and one of the Sumatran populations may already be extinct. In 2015, researchers announced that the Bornean rhinoceros had become extinct from the northern part of Borneo (Sabah, Malaysia); however, a tiny population was discovered in East Kalimantan in early 2016. (Full article...)
Banksia verticillata, commonly known as granite banksia or Albany banksia, is a species of shrub or (rarely) tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 3 m (10 ft) in height. It can grow taller to 5 m (16 ft) in sheltered areas, and much smaller in more exposed areas. This species has elliptic green leaves and large, bright golden yellow inflorescences or flower spikes, appearing in summer and autumn. The New Holland honeyeater (Phylidonyris novaehollandiae) is the most prominent pollinator, although several other species of honeyeater, as well as bees, visit the flower spikes.
A declared vulnerable species, it occurs in two disjunct populations on granite outcrops along the south coast of Western Australia, with the main population near Albany and a smaller population near Walpole, and is threatened by dieback (Phytophthora cinnamomi) and aerial canker (Zythiostroma). B. verticillata is killed by bushfire and new plants regenerate from seed afterwards. Populations take over a decade to produce seed and fire intervals of greater than twenty years are needed to allow the canopy seed bank to accumulate. (Full article...)- In Royal Botanic Gardens, Cranbourne
Isopogon anemonifolius, commonly known as broad-leaved drumsticks, is a shrub of the family Proteaceae that is native only to eastern New South Wales in Australia. It occurs naturally in woodland, open forest, and heathland on sandstone soils. I. anemonifolius usually ranges between one and two metres in height, and is generally smaller in exposed heathland. Its leaves are divided and narrow, though broader than those of the related Isopogon anethifolius, and have a purplish tinge during the cooler months. The yellow flowers appear during late spring or early summer and are displayed prominently. They are followed by round grey cones, which give the plant its common name drumsticks. The small hairy seeds are found in the old flower parts.
A long-lived plant reaching an age of up to 60 years, I. anemonifolius resprouts from its woody base, known as a lignotuber, after bushfire. Seedlings appear in the year following a fire. Although I. anemonifolius was collected by Daniel Solander in 1770, it was not described until 1796 by Richard Salisbury. Several varieties have been named, though none are now recognised as distinct. It was first cultivated in the United Kingdom in 1791. I. anemonifolius grows readily in the garden if located in a sunny or part-shaded spot with sandy soil and good drainage. (Full article...) - Flower spike of B. coccinea
Little Grove, Albany
Banksia coccinea, commonly known as the scarlet banksia, waratah banksia or Albany banksia, is an erect shrub or small tree in the family Proteaceae. Its distribution in the wild is along the south west coast of Western Australia, from Denmark to the Stokes National Park, and north to the Stirling Range, growing on white or grey sand in shrubland, heath or open woodland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has oblong leaves, which are 3–9 cm (1.2–3.5 in) long and 2–7 cm (0.8–2.8 in) wide. The prominent red and white flower spikes appear mainly in the spring. As they age they develop small follicles that store seeds until opened by fire. Though widely occurring, it is highly sensitive to dieback and large populations of plants have succumbed to the disease.
Collected and described by Robert Brown in the early 19th century, Banksia coccinea appears to be most closely related to Banksia speciosa and B. baxteri. Banksia coccinea plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. Widely considered one of the most attractive Banksia species, B. coccinea is a popular garden plant and one of the most important Banksia species for the cut flower industry; it is grown commercially in several countries including Australia, South Africa, Canada, the United States, New Zealand and Israel. In cultivation, B. coccinea grows well in a sunny location on well-drained soil, but it cannot survive in areas with humid or wet summers. (Full article...) - Ice core sample taken from drill. Photo by Lonnie Thompson, Byrd Polar Research Center
An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper, and an ice core contains ice formed over a range of years. Cores are drilled with hand augers (for shallow holes) or powered drills; they can reach depths of over two miles (3.2 km), and contain ice up to 800,000 years old.
The physical properties of the ice and of material trapped in it can be used to reconstruct the climate over the age range of the core. The proportions of different oxygen and hydrogen isotopes provide information about ancient temperatures, and the air trapped in tiny bubbles can be analysed to determine the level of atmospheric gases such as carbon dioxide. Since heat flow in a large ice sheet is very slow, the borehole temperature is another indicator of temperature in the past. These data can be combined to find the climate model that best fits all the available data. (Full article...) - Galileo image of 243 Ida. The dot to the right is its moon Dactyl.
Ida, minor planet designation 243 Ida, is an asteroid in the Koronis family of the asteroid belt. It was discovered on 29 September 1884 by Austrian astronomer Johann Palisa at Vienna Observatory and named after a nymph from Greek mythology. Later telescopic observations categorized Ida as an S-type asteroid, the most numerous type in the inner asteroid belt. On 28 August 1993, Ida was visited by the uncrewed Galileo spacecraft while en route to Jupiter. It was the second asteroid visited by a spacecraft and the first found to have a natural satellite.
Ida's orbit lies between the planets Mars and Jupiter, like all main-belt asteroids. Its orbital period is 4.84 years, and its rotation period is 4.63 hours. Ida has an average diameter of 31.4 km (19.5 mi). It is irregularly shaped and elongated, apparently composed of two large objects connected together. Its surface is one of the most heavily cratered in the Solar System, featuring a wide variety of crater sizes and ages. (Full article...)
Выбранное изображение
| Предоставлено: НАСА. |
Deep Impact - космический зонд НАСА, предназначенный для изучения состава недр кометы Tempel 1 . В 5:52 UTC 4 июля 2005 г. одна секциязонда Deep Impact успешно ударила по ядру кометы, выкапывая обломки изнутри ядра. Фотографии столкновения показали, что комета была более пыльной и менее ледяной, чем ожидалось. В результате удара образовалось большое яркое облако пыли, которое закрыло вид на кратер от удара.
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Избранная биография
Эмиль Адольф фон Беринг (15 марта 1854 - 31 марта 1917) родился в Хансдорфе, Эйлау, Германия (как Эмиль Адольф Беринг). Между 1874 г. и 1878 г. , он изучал медицину в Военно - медицинской академии в Берлине . В основном он был военным врачом, а затем стал профессором гигиены медицинского факультета Марбургского университета . Беринг был первооткрывателем антитоксина от дифтерии и благодаря этому и благодаря своему вкладу в изучение иммунитета приобрел большую репутацию. Он получил первую Нобелевскую премию по физиологии и медицине в 1901 году.за разработку сывороточной терапии против дифтерии (над этим работал Эмиль Ру ) и столбняка . Первые были бичом населения, особенно детей, тогда как другие были основной причиной смерти в войнах, убивая раненых.
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Вы знали...
- ... этот космический художник Джон Ломберг (на фото) был главным художественным соавтором Карла Сагана во многих проектах, таких как " Космос" и " Золотая пластинка Вояджера" ?
- ... что астронавт НАСА Стивен Робинсон провел 497 часов в космосе ?
- ... что Отниэль Чарльз Марш назвал два вида динозавра Coelurus из одного карьера , не зная, что кости принадлежали одному и тому же скелету?
- ... что образец типа из Dromicosuchus имели повреждения его челюсти и шеи , которые могут быть нанесены зубами большого плотоядного он был найден под?
- ... что научное название обычного австралийского садового грибка Aseroë rubra означает «отвратительный красный сок»?
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Новости науки
- 24 февраля 2021 г. -
- Ученые обнаружили в Узбекистане ископаемое динозавра Dzharatitanis kingi , похожее на диплодока . Это первый динозавр такого рода, обнаруженный в Азии . (Новый ученый)
- 17 февраля 2021 года - Открытия экзопланет
- Астрономы объявляют об открытии HD 110082 b , экзопланеты под Нептуном, которая в три раза больше Земли и вращается вокруг относительно молодой звезды. (Phys.org)
- 5 февраля 2021 г. -
- Ученые , принадлежащие к немецким - малагасийским экспедициям объявляют об открытии брукезии Наны , ящерицу нашли на Мадагаскаре. Размер тела самца составляет всего 13,5 миллиметра (0,5 дюйма), это потенциально самая маленькая рептилия на Земле. (BBC)
- 22 января 2021 г. - пандемия COVID-19
- Группа ученых, консультирующая британское правительство, объявляет, что вариант, впервые обнаруженный в Соединенном Королевстве, на 30% более смертоносен, чем исходный вирус SARS-CoV-2 . (Форбс)
- 19 января 2021 года - Открытия экзопланет
- Ученые выяснили, что WASP-107b - это супер-пуховик . WASP-107b - это экзопланета того же размера, что и Юпитер, но с одной десятой массы, расположенная на расстоянии 212 световых лет от Земли . (Новости CBS) (Новости науки)
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