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Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe.
The earliest written records of identifiable predecessors to modern science come from Ancient Egypt and Mesopotamia from around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped the Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age and later by the efforts of Byzantine Greek scholars who brought Greek manuscripts from the dying Byzantine Empire to Western Europe in the Renaissance.
The recovery and assimilation of Greek works and Islamic inquiries into Western Europe from the 10th to 13th century revived "natural philosophy", which was later transformed by the Scientific Revolution that began in the 16th century as new ideas and discoveries departed from previous Greek conceptions and traditions. The scientific method soon played a greater role in knowledge creation and it was not until the 19th century that many of the institutional and professional features of science began to take shape, along with the changing of "natural philosophy" to "natural science".
Modern science is typically divided into three major branches: natural sciences (e.g., biology, chemistry, and physics), 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, because they do not rely on empirical evidence. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as in engineering and medicine.
New knowledge in science is advanced by research from scientists who are motivated by curiosity about the world and a desire to solve problems. Contemporary scientific research is highly collaborative and is usually done by teams in academic and research institutions, government agencies, and companies. The practical impact of their work has led to the emergence of science policies that seek to influence the scientific enterprise by prioritizing the ethical and moral development of commercial products, armaments, health care, public infrastructure, and environmental protection. (Full article...)
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Featured articles are displayed here, which represent some of the best content on English Wikipedia.
The Horncastle boar's head is an early seventh-century Anglo-Saxon ornament depicting a boar that probably was once part of the crest of a helmet. It was discovered in 2002 by a metal detectorist searching in the town of Horncastle, Lincolnshire. It was reported as found treasure and acquired for £15,000 by the City and County Museum, where it is on permanent display.
The fragment is 40 mm (1.6 in) long and made of silver. Its elongated head is semi-naturalistic, depicting a crouching quadruped on either side of the skull, divided by a mane along the centre. The boar's eyes are formed from garnet, and its eyebrows, skull, mouth, tusks, and snout are gilded. Its head is hollow; in the space underneath, which was filled with soil and plant matter when found, are three rivets that would have attached it to a larger object, probably a helmet. The fragment would probably have formed the crest terminal of one of the "crested helmets" used in Northern Europe during the sixth through eleventh centuries. (Full article...)
The blue whale (Balaenoptera musculus) is a marine mammal and a baleen whale. Reaching a maximum confirmed length of 29.9 meters (98 ft) and weighing up to 199 tonnes (196 long tons; 219 short tons), it is the largest animal known ever to have existed. The blue whale's long and slender body can be of various shades of greyish-blue dorsally and somewhat lighter underneath. Four subspecies are recognized: B. m. musculus in the North Atlantic and North Pacific, B. m. intermedia in the Southern Ocean, B. m. brevicauda (the pygmy blue whale) in the Indian Ocean and South Pacific Ocean, B. m. indica in the Northern Indian Ocean. There is also a population in the waters off Chile that may constitute a fifth subspecies.
In general, blue whale populations migrate between their summer feeding areas near the poles and their winter breeding grounds near the tropics. There is also evidence of year-round residencies, and partial or age/sex-based migration. Blue whales are filter feeders; their diet consists almost exclusively of krill. They are generally solitary or gather in small groups, and have no well-defined social structure other than mother-calf bonds. The fundamental frequency for blue whale vocalizations ranges from 8 to 25 Hz and the production of vocalizations may vary by region, season, behavior, and time of day. Orcas are their only natural predators. (Full article...)
The russet sparrow (Passer cinnamomeus), also called the cinnamon or cinnamon tree sparrow, is a passerine bird of the sparrow family Passeridae. A chunky little seed-eating bird with a thick bill, it has a body length of 14 to 15 cm (5.5–5.9 in). Its plumage is mainly warm rufous above and grey below. It exhibits sexual dimorphism, with the plumage of both sexes patterned similarly to that of the corresponding sex of house sparrow. Its vocalisations are sweet and musical chirps, which when strung together form a song.
Three subspecies are recognised, differing chiefly in the yellowness of their underparts. The subspecies rutilans and intensior breed in parts of eastern Asia, where they are usually found in light woodland, and the subspecies cinnamomeus breeds in the Himalayas, where it is usually associated with terrace cultivation. The russet sparrow is the typical sparrow of human habitations in towns where the house and Eurasian tree sparrows are absent. In the southern part of its range, the russet sparrow prefers higher altitudes, but in the north it breeds by the sea. The russet sparrow is known well enough in the Himalayas to have a distinct name in some languages, and is depicted in Japanese art. (Full article...)
1893 illustrations of the first known carpometacarpus wing-bone
The Mauritius sheldgoose (Alopochen mauritiana), also known as the Mauritius shelduck, is an extinct species of sheldgoose that was endemic to the island of Mauritius. While geese were mentioned by visitors to Mauritius in the 17th century, few details were provided by these accounts. In 1893, a carpometacarpus wing-bone and a pelvis from the Mare aux Songes swamp were used to name a new species of comb duck, Sarcidiornis mauritianus. These bones were connected to the contemporary accounts of geese and later determined to belong to a species related to the Egyptian goose, and placed in the sheldgoose genus Alopochen. The Mauritius and Réunion sheldgoose may have descended from Egyptian geese that colonised the Mascarene islands.
One contemporary account states that the Mauritius sheldgoose had wings that were half black and half white, and that they were not very large. It may also be depicted in one illustration. Fossil elements show that it was smaller than the Egyptian goose, but with more robust legs. Little is known about the habits of the Mauritius sheldgoose, accounts indicate they were very tame, were grazers, lived in groups, and usually stayed on the north side of the island except for during the dry season when they were forced to the other side to drink. Their robust legs indicates they were becoming more terrestrial, which is supported by accounts stating they avoided water. The species was considered highly palatable by travellers, and while abundant in 1681, it declined quickly thereafter, being declared extinct in 1698. It was probably driven to extinction due to overhunting and predation by introduced animals, particularly cats. (Full article...)
Lunar Module 1 being mated to the Spacecraft–LM adapter (SLA) in preparation for launch as Apollo 5
Apollo 5 (launched January 22, 1968), also known as AS-204, was the uncrewed first flight of the Apollo Lunar Module (LM) that would later carry astronauts to the surface of the Moon. The Saturn IB rocket bearing the LM lifted off from Cape Kennedy on January 22, 1968. The mission was successful, though due to programming problems an alternate mission to that originally planned was executed.
Like Apollo 4, this flight was long delayed, due in part to setbacks in development of the LM, manufactured by Grumman Aircraft. The original Saturn IB rocket that was to take the first LM (LM-1) to space was taken down during the delays and replaced with the one that would have launched Apollo 1 if the spacecraft fire that killed three astronauts had not taken place. LM-1 arrived at the Kennedy Space Center in June 1967; the following months were occupied in testing and placing the LM atop the Saturn IB. After final delays due to equipment trouble, the countdown began on January 21, 1968, and the space vehicle was launched the following day. (Full article...)- Triangulum Australe is a small constellation in the far Southern Celestial Hemisphere. Its name is Latin for "the southern triangle", which distinguishes it from Triangulum in the northern sky and is derived from the acute, almost equilateral pattern of its three brightest stars. It was first depicted on a celestial globe as Triangulus Antarcticus by Petrus Plancius in 1589, and later with more accuracy and its current name by Johann Bayer in his 1603 Uranometria. The French explorer and astronomer Nicolas Louis de Lacaille charted and gave the brighter stars their Bayer designations in 1756.
Alpha Trianguli Australis, known as Atria, is a second-magnitude orange giant and the brightest star in the constellation, as well as the 42nd-brightest star in the night sky. Completing the triangle are the two white main sequence stars Beta and Gamma Trianguli Australis. Although the constellation lies in the Milky Way and contains many stars, deep-sky objects are not prominent. Notable features include the open cluster NGC 6025 and planetary nebula NGC 5979. (Full article...)
Banksia scabrella, commonly known as the Burma Road banksia, is a species of woody shrub in the genus Banksia. It is classified in the series Abietinae, a group of several species of shrubs with small round or oval inflorescences. It occurs in a number of isolated populations south of Geraldton, Western Australia, with the largest population being south and east of Mount Adams. Found on sandy soils in heathland or shrubland, it grows to 2 m (7 ft) high and 3 m (10 ft) across with fine needle-like leaves. Appearing in spring and summer, the inflorescences are round to oval in shape and tan to cream with purple styles. Banksia scabrella is killed by fire and regenerates by seed.
Originally collected in 1966, B. scabrella was one of several species previously considered to be forms of Banksia sphaerocarpa, before it was finally described by banksia expert Alex George in his 1981 revision of the genus. Like many members of the Abietinae, it is rarely seen in cultivation; however, it has been described as having horticultural potential. (Full article...)
Several plants in cultivation
Drosera regia, commonly known as the king sundew, is a carnivorous plant in the sundew genus Drosera that is endemic to a single valley in South Africa. The genus name Drosera comes from the Greek word droseros, meaning "dew-covered". The specific epithet regia is derived from the Latin for "royal", a reference to the "striking appearance" of the species. Individual leaves can reach 70 cm (28 in) in length. It has many unusual relict characteristics not found in most other Drosera species, including woody rhizomes, operculate pollen, and the lack of circinate vernation in scape growth. All of these factors, combined with molecular data from phylogenetic analysis, contribute to the evidence that D. regia possesses some of the most ancient characteristics within the genus. Some of these are shared with the related Venus flytrap (Dionaea muscipula), which suggests a close evolutionary relationship.
The tentacle-covered leaves can capture large prey, such as beetles, moths, and butterflies. The tentacles of all Drosera species have special stalked glands on the leaf's upper surface that produce a sticky mucilage. The leaves are considered active flypaper traps that respond to captured prey by bending to surround it. In its native fynbos habitat, the plants compete for space with native marsh grasses and low evergreen shrubs. Of the two known populations of D. regia, the higher altitude site appears to be overgrown and is essentially extirpated. The lower altitude site is estimated to have about 50 mature plants, making it the most endangered Drosera species, since it is threatened with extinction in the wild. It is often cultivated by carnivorous plant enthusiasts, and a single cultivar has been registered. (Full article...)
Europa in true colour, with its surface predominantly white. Imaged on 29 September 2022 by the Juno spacecraft.
Europa /jʊˈroʊpə/ (
listen), 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).
Slightly smaller than Earth's Moon, Europa is primarily made of silicate rock and has a water-ice crust and probably an iron–nickel core. It has a very thin atmosphere, composed primarily of oxygen. Its white-beige surface is striated by light tan cracks and streaks, but craters are relatively few. In addition to Earth-bound telescope observations, Europa has been examined by a succession of space-probe flybys, the first occurring in the early 1970s. In September 2022, the Juno spacecraft flew within about 200 miles of Europa for a more recent close-up view. (Full article...)- Symphyotrichum lateriflorum (formerly Aster lateriflorus) is a species of flowering plant in the aster family (Asteraceae). Commonly known as calico aster, starved aster, and white woodland aster, it is native to eastern and central North America. It is a perennial and herbaceous plant that may reach heights up to 120 centimeters (4 feet) and widths up to 30 centimeters (1 foot).
The flowers of calico aster are small compared to most Symphyotrichum species. They have an average of 7–15 short white ray florets, which are rarely tinted pink or purple. The flower centers, composed of disk florets, begin as cream to yellow and often become pink, purple, or brown as they mature. There are roughly 8–16 disk florets, each with five lobes that strongly reflex (bend backwards) when open. The mostly hairless leaves have a characteristic hairy midrib on their back faces, and branching is usually horizontal or in what can appear to be a zigzag pattern. Flower heads grow along one side of the branches and sometimes in clusters at the ends. (Full article...) 
Rundkvist on a dig in Aska, 2020
Martin Rundkvist (born 4 April 1972) is a Swedish archaeologist and associate professor at the University of Łódź in Poland. His research focuses on the Bronze, Iron, and Middle Ages of Scandinavia, including significant excavations in the province of Östergötland.
Rundkvist has studied and excavated various sites in Sweden, particularly in the country's south. In 2003 and 2004, he published a three-volume work which doubled as his PhD dissertation, cataloguing the finds from Barshalder, the largest prehistoric cemetery on the Swedish island of Gotland. A subsequent book identified nine possible regional power centres in Östergötland, and attempted to determine where the "Beowulfian mead halls" of the day once stood. Excavating years later at one of these sites, Aska, Rundkvist uncovered the foundations of a large mead hall, and 30 ornate gold figures that might have represented gods or royals. In other works, Rundkvist has excavated a Viking boat grave, and analysed both the placement of deposited artefacts in the landscape and the lifestyles of the Scandinavian élite during the Middle Ages. (Full article...)
Cast of a Ceratosaurus skeleton from the Cleveland Lloyd Quarry, on display at the Natural History Museum of Utah
Ceratosaurus /ˌsɛrətoʊˈsɔːrəs/ (from Greek κέρας/κέρατος, keras/keratos meaning "horn" and σαῦρος sauros meaning "lizard") was a carnivorous theropod dinosaur in the Late Jurassic period (Kimmeridgian to Tithonian). The genus was first described in 1884 by American paleontologist Othniel Charles Marsh based on a nearly complete skeleton discovered in Garden Park, Colorado, in rocks belonging to the Morrison Formation. The type species is Ceratosaurus nasicornis.
The Garden Park specimen remains the most complete skeleton known from the genus, and only a handful of additional specimens have been described since. Two additional species, Ceratosaurus dentisulcatus and Ceratosaurus magnicornis, were described in 2000 from two fragmentary skeletons from the Cleveland-Lloyd Quarry of Utah and from the vicinity of Fruita, Colorado. The validity of these additional species has been questioned, however, and all three skeletons possibly represent different growth stages of the same species. In 1999, the discovery of the first juvenile specimen was reported. In 2000, a partial specimen was excavated and described from the Lourinhã Formation of Portugal, providing evidence for the presence of the genus outside of North America. Fragmentary remains have also been reported from Tanzania, Uruguay, and Switzerland, although their assignment to Ceratosaurus is currently not accepted by most paleontologists. (Full article...)
The secretarybird or secretary bird (Sagittarius serpentarius) is a large, mostly terrestrial bird of prey. Endemic to Africa, it is usually found in the open grasslands and savanna of the sub-Saharan region. John Frederick Miller described the species in 1779. Although a member of the order Accipitriformes, which also includes many other diurnal birds of prey such as kites, hawks, vultures, and harriers, it is placed in its own family, Sagittariidae.
The secretarybird is instantly recognizable as a very large bird with an eagle-like body on crane-like legs that give the bird a height of as much as 1.3 m (4 ft 3 in). The sexes are similar in appearance. Adults have a featherless red-orange face and predominantly grey plumage, with a flattened dark crest and black flight feathers and thighs. It also has very long eyelashes. (Full article...)
Adenanthos cuneatus, also known as coastal jugflower, flame bush, bridle bush and sweat bush, is a shrub of the family Proteaceae, native to the south coast of Western Australia. The French naturalist Jacques Labillardière originally described it in 1805. Within the genus Adenanthos, it lies in the section Adenanthos and is most closely related to A. stictus. A. cuneatus has hybridized with four other species of Adenanthos. Growing to 2 m (6 ft 7 in) high and wide, it is erect to prostrate in habit, with wedge-shaped lobed leaves covered in fine silvery hair. The single red flowers are insignificant, and appear all year, though especially in late spring. The reddish new growth occurs over the summer.
It is sensitive to Phytophthora cinnamomi dieback, hence requiring a sandy soil and good drainage to grow in cultivation, its natural habitat of sandy soils in heathland being an example. Its pollinators include bees, honey possum, silvereye and honeyeaters, particularly the western spinebill. A. cuneatus is grown in gardens in Australia and the western United States, and a dwarf and prostrate form are commercially available. (Full article...)
Male and female (left-right)
Call
The pintail or northern pintail (Anas acuta) is a duck species with wide geographic distribution that breeds in the northern areas of Europe and across the Palearctic and North America. It is migratory and winters south of its breeding range to the equator. Unusually for a bird with such a large range, it has no geographical subspecies if the possibly conspecific duck Eaton's pintail is considered to be a separate species.
This is a large duck, and the male's long central tail feathers give rise to the species' English and scientific names. Both sexes have blue-grey bills and grey legs and feet. The drake is more striking, having a thin white stripe running from the back of its chocolate-coloured head down its neck to its mostly white undercarriage. The drake also has attractive grey, brown, and black patterning on its back and sides. The hen's plumage is more subtle and subdued, with drab brown feathers similar to those of other female dabbling ducks. Hens make a coarse quack and the drakes a flute-like whistle. (Full article...)
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More did you know...
- ...that in recent years Mediterranean alcoholic beverages (pictured) have been subject of intense scientific study?
- ...that the supermassive black hole at the center of the quasar OJ287 has been measured as weighing 18 billion times the mass of the Sun, six times heavier than the previous record holder?
- ...that the origins of Castle Lake (pictured) in California date to the Pleistocene Era (more than 10,000 years ago) when a glacier carved a basin in the location of the current lake?
- ...that 2002's Hurricane Elida was the first hurricane to be observed by the MERIS sensor aboard the ESA's satellite Envisat?
- ...that for a pure wave motion in fluid dynamics, the Stokes drift velocity is the average velocity when following a specific fluid parcel as it travels with the fluid flow?
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Science News
- 24 May 2023 –
- In a medical first, a paralyzed man is able to walk naturally through the use of electronic brain implants implanted by Swiss scientists. (BBC News)
- 3 May 2023 –
- Researchers announce the successful extraction of ancient DNA from a 20,000 year old elk-tooth pendant found in Denisova Cave. (Reuters)
- 5 April 2023 – Discoveries of exoplanets
- Scientists discover bursts of radiation in radio wavelengths on the exoplanet YZ Ceti b, which is part of the YZ Ceti system. The studies are published in the Nature Astronomy journal. (The Jerusalem Post)
- 1 April 2023 –
- Professor Alan Jamieson of the University of Western Australia's Minderoo-UWA Deep Sea Research Centre announces that his team has captured footage of a snailfish species, Pseudoliparis belyaevi, swimming at 8,336 metres (27,349 ft) in the Izu–Ogasawara Trench off Japan's southern coast. This is the lowest depth recorded for any fish, and closest to the estimated maximum depth possible for fish to survive. (BBC News)
- 27 March 2023 –
- Scientists discover lunar water samples in tiny glass beads from the Moon in studies published by the Nature Geoscience journal. (ABC News)
- 21 March 2023 – Astrobiology
- Scientists find the presence of uracil, one of the components of RNA, and vitamin B3 in the samples from asteroid 162173 Ryugu. (CNN)
General images -
Diagram from William Gilbert's De Magnete, a pioneering work of experimental science (from Scientific Revolution)
Francis Bacon was a pivotal figure in establishing the scientific method of investigation. Portrait by Frans Pourbus the Younger (1617). (from Scientific Revolution)
Alessandro Volta demonstrates the first electrical cell to Napoleon in 1801. (from History of science)
Matteo Ricci (left) and Xu Guangqi (right) in Athanasius Kircher, La Chine ... Illustrée, Amsterdam, 1670. (from Scientific Revolution)
Galileo Galilei, father of modern science. (from History of science)
The 1698 Savery Engine was the first successful steam engine (from Scientific Revolution)
Image of veins from William Harvey's Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus. Harvey demonstrated that blood circulated around the body, rather than being created in the liver. (from Scientific Revolution)
Vesalius's intricately detailed drawings of human dissections in Fabrica helped to overturn the medical theories of Galen. (from Scientific Revolution)
The atomic bomb ushered in "Big Science" in physics. (from History of science)
Statue of Roger Bacon at the Oxford University Museum of Natural History (from History of science)
Lui Hui's Survey of sea island (from History of science)
An ivory set of Napier's Bones, an early calculating device invented by John Napier (from Scientific Revolution)
Otto von Guericke's experiments on electrostatics, published 1672 (from Scientific Revolution)
Alfred Wegener in Greenland in the winter of 1912–13. He is most remembered as the originator of continental drift hypothesis by suggesting in 1912 that the continents are slowly drifting around the Earth. (from History of science)
A modern replica of Han dynasty polymath scientist Zhang Heng's seismometer of 132 CE (from History of science)
Star list with distance information, Uruk (Iraq), 320-150 BCE, the list gives each constellation, the number of stars and the distance information to the next constellation in ells (from History of science)
The Royal Society had its origins in Gresham College in the City of London, and was the first scientific society in the world. (from Scientific Revolution)
Schematic of the Antikythera mechanism (150–100 BCE). (from History of science)
Model of DNA with David Deutsch, proponent of invariant scientific explanations (2009) (from Scientific method)
Adam Smith wrote The Wealth of Nations, the first modern work of economics (from History of science)
Precession of the perihelion – exaggerated in the case of Mercury, but observed in the case of S2's apsidal precession around Sagittarius A* (from Scientific method)
Ptolemaic model of the spheres for Venus, Mars, Jupiter, and Saturn. Georg von Peuerbach, Theoricae novae planetarum, 1474. (from Scientific Revolution)
Title page from The Sceptical Chymist, a foundational text of chemistry, written by Robert Boyle in 1661 (from Scientific Revolution)
Portrait of Galileo Galilei by Leoni (from Scientific Revolution)
The Ebers Papyrus (c. 1550 BCE) from ancient Egypt (from History of science)
Newton's Opticks or a treatise of the reflections, refractions, inflections and colours of light (from Scientific Revolution)
One of the oldest surviving fragments of Euclid's Elements, found at Oxyrhynchus and dated to c. 100 CE. (from History of science)
Plato's Academy. 1st century mosaic from Pompeii (from History of science)
Isaac Newton in a 1702 portrait by Godfrey Kneller (from Scientific Revolution)
Air pump built by Robert Boyle. Many new instruments were devised in this period, which greatly aided in the expansion of scientific knowledge. (from Scientific Revolution)
Watson and Crick used many aluminium templates like this one, which is the single base Adenine (A), to build a physical model of DNA in 1953. (from History of science)
In mid-July 1837 Charles Darwin started his "B" notebook on the Transmutation of Species, and on page 36 wrote "I think" above his first evolutionary tree. (from History of science)
Ancient India was an early leader in metallurgy, as evidenced by the wrought-iron Pillar of Delhi. (from History of science)
The French Academy of Sciences was established in 1666. (from Scientific Revolution)
Isaac Newton's Principia, developed the first set of unified scientific laws. (from Scientific Revolution)
The frontispiece of the Vienna Dioscurides, which shows a set of seven famous physicians (from History of science)
Clay models of animal livers dating between the nineteenth and eighteenth centuries BCE, found in the royal palace at Mari in what is now Syria (from History of science)
Einstein's official portrait after receiving the 1921 Nobel Prize in Physics (from History of science)
Isaac Newton initiated classical mechanics in physics. (from History of science)
15th-century manuscript of Avicenna's The Canon of Medicine. (from History of science)
The scientific method is often represented as an ongoing process. This diagram represents one variant, and there are many others. (from Scientific method)
Archimedes used the method of exhaustion to approximate the value of π. (from History of science)
Portrait of Johannes Kepler (from Scientific Revolution)
One possible signature of a Higgs boson from a simulated proton–proton collision. It decays almost immediately into two jets of hadrons and two electrons, visible as lines. (from History of science)
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