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Emil Adolf von Behring (March 15, 1854 – March 31, 1917) was born at Hansdorf, Eylau, Germany (as Emil Adolf Behring). Between 1874 and 1878, he studied medicine at the Army Medical College in Berlin. He was mainly a military doctor and then became Professor of Hygienics within the Faculty of Medicine at the University of Marburg. Behring was the discoverer of diphtheria antitoxin and attained a great reputation by that means and by his contributions to the study of immunity. He won the first Nobel Prize in Physiology or Medicine in 1901 for developing a serum therapy against diphtheria (this was worked on with Emile Roux) and tetanus. The former had been a scourge of the population, especially children, whereas the other was a leading cause of death in wars, killing the wounded.
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Science (from the Latin word scientia, meaning "knowledge") is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.
The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3500 to 3000 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped 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. 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 that consist of the natural sciences (e.g., biology, chemistry, and physics), which study nature in the broadest sense; 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 abstract concepts. There is disagreement, however, on whether the formal sciences actually constitute a science as they do not rely on empirical evidence. Disciplines that use existing scientific knowledge for practical purposes, such as engineering and medicine, are described as applied sciences.
Science is based on research, which is commonly conducted in academic and research institutions as well as in government agencies and companies. The practical impact of scientific research has led to the emergence of science policies that seek to influence the scientific enterprise by prioritizing the development of commercial products, armaments, health care, and environmental protection.
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Hurricane Gert was a large tropical cyclone that caused extensive flooding and mudslides throughout Central America and Mexico in September 1993. The seventh named storm and third hurricane of the annual hurricane season, Gert originated as a tropical depression from a tropical wave over the southwestern Caribbean Sea on September 14. The next day, the cyclone briefly attained tropical storm strength before moving ashore in Nicaragua and proceeding through Honduras. It reorganized into a tropical storm over the Gulf of Honduras on September 17, but weakened back to a depression upon crossing the Yucatán Peninsula. Once over the warm waters of the Bay of Campeche, Gert quickly strengthened into a Category 2 hurricane by September 20. The hurricane made a final landfall on the Gulf Coast of Mexico near Tuxpan, Veracruz, with peak winds of 100 mph (155 km/h). The rugged terrain disrupted the cyclone's structure; Gert entered the Pacific Ocean as a depression near the state of Nayarit on September 21, where it briefly redeveloped a few strong thunderstorms before dissipating at sea five days later.
Gert's broad wind circulation produced widespread and heavy rainfall across Central America through September 15–17. Combined with saturated soil following Tropical Storm Bret's passage a month earlier, the rain triggered widespread floods and mudslides that isolated thousands of people across numerous communities. In Costa Rica, blustery weather destroyed a national park and led to significant losses in the agricultural and tourism sectors. Much of the Mosquito Coast of Nicaragua and Honduras endured overflowing rivers, engulfing cities, villages, and crops with mud and water. Gert's winds were at their strongest upon landfall in Mexico, yet the worst effects in the country were also due to freshwater flooding after an extreme rainfall event in the Huasteca region resulted in water accumulations as high as 31.41 inches (798 mm). An increasing number of major rivers burst their banks over a period of several days, fully submerging extensive areas of land around the Pánuco basin. Tens of thousands of residents were forced to evacuate as raging floodwaters demolished scores of structures in what was described as the region's worst disaster in 40 years.
The red-tailed black cockatoo (Calyptorhynchus banksii) also known as Banksian- or Banks' black cockatoo, is a large black cockatoo native to Australia. Adult males have a characteristic pair of bright red panels on the tail that gives the species its name. It is more common in the drier parts of the continent. Five subspecies are recognised, differing chiefly in beak size. Although the more northerly subspecies are widespread, the two southern subspecies, the forest red-tailed black cockatoo and the south-eastern red-tailed black cockatoo are under threat.
The species is usually found in eucalyptus woodlands, or along water courses. In the more northerly parts of the country, these cockatoos are commonly seen in large flocks. They are seed eaters and cavity nesters, and as such depend on trees with fairly large diameters, generally Eucalyptus. Populations in southeastern Australia are threatened by deforestation and other habitat alterations. Of the black cockatoos, the red-tailed is the most adaptable to aviculture, although black cockatoos are much rarer and much more expensive in aviculture outside Australia.
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.
The fruit bodies can reach heights of 18 cm (7.1 in) tall with caps that are up to 7.5 cm (3.0 in) wide. The tough woody stems are 1–2 cm (0.4–0.8 in) wide, thickening towards the base. Fruit bodies grow singly or scattered on the ground in fields, grasslands, or arid ecosystems. Other mushrooms with which A. deserticola might be confused include the desert fungus species Podaxis pistillaris and Montagnea arenaria. The edibility of Agaricus deserticola mushrooms is not known definitively. Formerly named Longula texensis (among several other synonyms), the fungus was transferred to the genus Agaricus in 2004 after molecular analysis showed it to be closely related to species in that genus. In 2010, its specific epithet was changed to deserticola after it was discovered that the name Agaricus texensis was illegitimate, having been previously published for a different species.- Crater is a small constellation in the southern celestial hemisphere. Its name is the latinization of the Greek krater, a type of cup used to water down wine. One of the 48 constellations listed by the second-century astronomer Ptolemy, it depicts a cup that has been associated with the god Apollo and is perched on the back of Hydra the water snake.
There is no star brighter than third magnitude in the constellation. Its two brightest stars, Delta Crateris of magnitude 3.56 and Alpha Crateris of magnitude 4.07, are ageing orange giant stars that are cooler and larger than the Sun. Beta Crateris is a binary star system composed of a white giant star and a white dwarf. Seven star systems have been found to host planets. A few notable galaxies, including Crater 2 and NGC 3981, and a famous quasar lie within the borders of the constellation. 
Red kite (Milvus milvus) in flight, showing remiges and rectrices
Flight feathers (Pennae volatus) are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (/ˈrɛmɪdʒiːz/), singular remex (/ˈriːmɛks/), while those on the tail are called rectrices (/rɛkˈtraɪsiːs/), singular rectrix (/ˈrɛktrɪks/). The primary function of the flight feathers is to aid in the generation of both thrust and lift, thereby enabling flight. The flight feathers of some birds have evolved to perform additional functions, generally associated with territorial displays, courtship rituals or feeding methods. In some species, these feathers have developed into long showy plumes used in visual courtship displays, while in others they create a sound during display flights. Tiny serrations on the leading edge of their remiges help owls to fly silently (and therefore hunt more successfully), while the extra-stiff rectrices of woodpeckers help them to brace against tree trunks as they hammer on them. Even flightless birds still retain flight feathers, though sometimes in radically modified forms.
The moult of their flight feathers can cause serious problems for birds, as it can impair their ability to fly. Different species have evolved different strategies for coping with this, ranging from dropping all their flight feathers at once (and thus becoming flightless for some relatively short period of time) to extending the moult over a period of several years.
The king brown snake (Pseudechis australis) is a species of highly venomous snake of the Elapidae family, native to northern, western, and Central Australia. Despite its common name, it is a member of the genus Pseudechis (black snakes) and only distantly related to true brown snakes. Its alternative common name is the mulga snake, although it lives in many habitats apart from mulga. First described by the English zoologist John Edward Gray in 1842, it is a robust snake up to 3.3 m (11 ft) long. It is variable in appearance, with individuals from northern Australia having tan upper-parts, while those from southern Australia are dark brown to blackish. The dorsal scales are two-toned, sometimes giving the snake a patterned appearance. Its underside is cream or white, often with orange splotches. The species is oviparous. The snake is considered to be a least-concern species according to the International Union for Conservation of Nature (IUCN), though may have declined with the spread of the cane toad.
The venom is not as potent as those of Australia's other dangerous snakes, but can still cause severe effects if delivered in large enough quantities. Its main effect is on striated muscle tissue, causing paralysis from muscle damage, and also commonly affects blood clotting (coagulopathy). There is often extensive pain and swelling, and rarely necrosis, at the site of the bite. Deaths from its bites have been recorded, the most recent being in 1969. Its victims are treated with black snake (not brown snake) antivenom.
The 1988 Atlantic hurricane season was a near average season that proved costly and deadly, with 15 tropical cyclones directly affecting land. The season officially began on June 1, 1988, and lasted until November 30, 1988, although activity began on May 30 when a tropical depression developed in the Caribbean Sea. The June through November dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. The first cyclone to attain tropical storm status was Alberto on August 8, nearly a month later than usual. The final storm of the year, Tropical Storm Keith, became extratropical on November 24.
The season produced 19 tropical depressions of which 12 attained tropical storm status. One tropical storm was operationally classified as a tropical depression but was reclassified in post-analysis. Five tropical cyclones reached hurricane status of which three became major hurricanes reaching Category 3 on the Saffir-Simpson Hurricane Scale.
Model of megalodon jaws at the American Museum of Natural History
Megalodon (Otodus megalodon), meaning "big tooth", is an extinct species of shark that lived approximately 23 to 3.6 million years ago (mya), during the Early Miocene to the Pliocene. It was formerly thought to be a member of the family Lamnidae and a close relative of the great white shark (Carcharodon carcharias). However, it is now classified into the extinct family Otodontidae, which diverged from the great white shark during the Early Cretaceous. Its genus placement is still debated, authors placing it in either Carcharocles, Megaselachus, Otodus, or Procarcharodon. This is because transitional fossils have been found showing that Megalodon is the final chronospecies of a lineage of giant sharks originally of the genus Otodus which evolved during the Paleocene.
While regarded as one of the largest and most powerful predators to have ever lived, megalodon is known from fragmentary remains, and its appearance and maximum size are uncertain. Scientists differ on whether it would have more closely resembled a stockier version of the great white shark, the whale shark (Rhincodon typus), the basking shark (Cetorhinus maximus) or the sand tiger shark (Carcharias taurus). Most estimates of megalodon's size extrapolate from teeth; with maximum length estimates up to 14.2–16 meters (47–52 ft) and average length estimates of 10.5 meters (34 ft). Estimates suggest their large jaws could exert a bite force of up to 108,500 to 182,200 newtons (24,400 to 41,000 lbf). Their teeth were thick and robust, built for grabbing prey and breaking bone.
Hurricane Ioke, also referred to as Typhoon Ioke, had the highest accumulated cyclone energy (ACE) of any tropical cyclone on record. The first storm to form in the Central Pacific in the 2006 Pacific hurricane season, Ioke was a record breaking, long-lived and extremely powerful storm that traversed the Pacific for 17 days, reaching the equivalent of Category 5 status on the Saffir–Simpson hurricane scale on three different occasions. It was the most intense hurricane ever recorded in the Central Pacific, as well as the fifth-most intense Pacific hurricane on record, tied with 1973's Hurricane Ava.
The cyclone developed in the Intertropical Convergence Zone on August 20 far to the south of Hawaii. Encountering warm waters, little wind shear, and well-defined outflow, Ioke intensified from a tropical depression to Category 4 status within 48 hours. Late on August 22 it rapidly weakened to Category 2 status before crossing over Johnston Atoll. Two days later favorable conditions again allowed for rapid strengthening, and Ioke attained Category 5 status on August 25 before crossing the International Date Line. As it continued westward its intensity fluctuated, and on August 31 it passed near Wake Island with winds of 155 mph (250 km/h). Ioke gradually weakened as it turned northwestward and northward, and by September 6 it had transitioned into an extratropical cyclone. The remnants of Ioke accelerated northeastward and ultimately crossed into the Bering Sea, and then the Gulf of Alaska.
Hurricane Gonzalo was the second tropical cyclone, after Hurricane Fay, to directly strike the island of Bermuda in a one-week time frame in October 2014, and was the first Category 4 Atlantic hurricane since Hurricane Ophelia in 2011. At the time, it was the strongest hurricane in the Atlantic since Igor in 2010.[1] Gonzalo struck Bermuda less than a week after the surprisingly fierce Hurricane Fay; 2014 was the first season in recorded history to feature two hurricane landfalls in Bermuda. A powerful Atlantic tropical cyclone that wrought destruction in the Leeward Islands and Bermuda, Gonzalo was the seventh named storm, sixth and final hurricane and only the second major hurricane of the below-average 2014 Atlantic hurricane season. The storm formed from a tropical wave on October 12, while located east of the Lesser Antilles. It made landfall on Antigua, Saint Martin, and Anguilla as a Category 1 hurricane, causing damage on those and nearby islands. Antigua and Barbuda sustained US$40 million in losses, and boats were abundantly damaged or destroyed throughout the northern Leeward Islands. The storm killed three people on Saint Martin and Saint Barthélemy. Gonzalo tracked northwestward as it intensified into a major hurricane. Eyewall replacement cycles led to fluctuations in the hurricane's structure and intensity, but on October 16, Gonzalo peaked with maximum sustained winds of 145 mph (230 km/h).
After Hurricane Fay caused extensive power outages on the island just days before, residents of Bermuda were forced to complete preparations for Gonzalo in haste. Banks, businesses, schools, and government offices closed in advance of the storm, while the Royal Navy ship HMS Argyll left its post in the Caribbean to provide Bermuda with emergency assistance. The cyclone gradually weakened before crossing directly over central Bermuda at Category 2 strength around 00:30 UTC on October 18. Gonzalo battered the island with wind gusts as high as 144 mph (232 km/h), downing hundreds of trees and creating widespread roof damage. At the height of the storm, about 31,000 out of 36,000 total electricity customers were without power; service was not fully restored until early November. Many roads were impassable immediately following the hurricane, and in many cases the damage done by Gonzalo was indistinguishable from that of Fay. Bermuda Regiment soldiers and sailors from the Argyll took part in initial cleanup and repairs on the territory, and preliminary assessments revealed that the storm did not compare to the devastation of Hurricane Fabian in 2003. Catastrophe modelling firms estimated that Bermuda suffered at least $200 million in insured losses, and despite the heavy disruptions, no deaths or serious injuries were reported there.
Io (/ˈaɪ.oʊ/), or Jupiter I, is the innermost and third-largest of the four Galilean moons of the planet Jupiter. It is the fourth-largest moon in the Solar System, has the highest density of all of them, and has the lowest amount of water (by atomic ratio) of any known astronomical object in the Solar System. It was discovered in 1610 by Galileo Galilei and was named after the mythological character Io, a priestess of Hera who became one of Zeus's lovers.
With over 400 active volcanoes, Io is the most geologically active object in the Solar System. This extreme geologic activity is the result of tidal heating from friction generated within Io's interior as it is pulled between Jupiter and the other Galilean moons—Europa, Ganymede and Callisto. Several volcanoes produce plumes of sulfur and sulfur dioxide that climb as high as 500 km (300 mi) above the surface. Io's surface is also dotted with more than 100 mountains that have been uplifted by extensive compression at the base of Io's silicate crust. Some of these peaks are taller than Mount Everest, the highest point on Earth's surface. Unlike most moons in the outer Solar System, which are mostly composed of water ice, Io is primarily composed of silicate rock surrounding a molten iron or iron sulfide core. Most of Io's surface is composed of extensive plains with a frosty coating of sulfur and sulfur dioxide.
Reconstructed skeleton at the National Museum of Nature and Science, Tokyo. The postcranium is based on remains that cannot be confidently attributed to the animal.
Irritator is a genus of spinosaurid dinosaur that lived in what is now Brazil during the Albian stage of the Early Cretaceous Period, about 110 million years ago. It is known from a nearly complete skull found in the Romualdo Formation of the Araripe Basin. Fossil dealers had acquired this skull and illegally sold it to the State Museum of Natural History Stuttgart. In 1996, the specimen became the holotype of the type species Irritator challengeri. The genus name comes from the word "irritation", reflecting the feelings of paleontologists who found the skull had been heavily damaged and altered by the collectors. The species name is an homage to the fictional character Professor Challenger from Arthur Conan Doyle's novels.
Some paleontologists regard Angaturama limai—known from a snout tip that was described later in 1996—as a potential junior synonym of Irritator. Both animals hail from the same stratigraphic units of the Araripe Basin. It was also previously proposed that Irritator and Angaturama's skull parts belonged to the same specimen. Although this has been cast into doubt, more overlapping fossil material is needed to confirm whether they are the same animal or not. Other spinosaurid skeletal material, some of which could belong to Irritator or Angaturama, was retrieved from the Romualdo Formation, allowing for a replica skeleton to be made and mounted for display at the National Museum of Rio de Janeiro in 2009.
Russula emetica, commonly known as the sickener, emetic russula, or vomiting russula, is a basidiomycete mushroom, and the type species of the genus Russula. It has a red, convex to flat cap up to 8.5 cm (3.3 in) in diameter, with a cuticle that can be peeled off almost to the centre. The gills are white to pale cream, and closely spaced. A smooth white stem measures up to 10.5 cm (4.1 in) long and 2.4 cm (0.9 in) thick. First described in 1774, the mushroom has a wide distribution in the Northern Hemisphere, where it grows on the ground in damp woodlands in a mycorrhizal association with conifers, especially pine.
The mushroom's common names refer to the gastrointestinal distress they cause when consumed raw. The flesh is extremely peppery, but this offensive taste, along with its toxicity, can be removed by parboiling or pickling. Although it used to be widely eaten in Russia and eastern European countries, it is generally not recommended for consumption. There are many similar Russula species that have a red cap with white stem and gills, some of which can be reliably distinguished from R. emetica only by microscopic characteristics.
Extremely Severe Cyclonic Storm Chapala was a powerful tropical cyclone that caused moderate damage in Somalia and Yemen during November 2015. Chapala was the third named storm of the 2015 North Indian Ocean cyclone season. It developed as a depression on 28 October off western India, and strengthened a day later into a cyclonic storm. Chapala then rapidly intensified amid favorable conditions. On 30 October, the India Meteorological Department (IMD) estimated that Chapala attained peak three-minute sustained winds of 215 km/h (130 mph). The American-based Joint Typhoon Warning Center (JTWC) estimated sustained winds of 240 km/h (150 mph), making Chapala among the strongest cyclones on record in the Arabian Sea. After peak intensity, Chapala skirted the Yemeni island of Socotra on 1 November, becoming the first hurricane-force storm there since 1922. High winds and heavy rainfall resulted in an island-wide power outage, and severe damage was compounded by Cyclone Megh, which struck Yemen a week later.
While Chapala encountered less favorable conditions after leaving Socotra, it maintained much of its intensity; upon entering the Gulf of Aden on 2 November, it became the strongest known cyclone in that body of water. Chapala brushed the northern coast of Somalia, killing tens of thousands of animals and wrecking 350 houses. Ahead of the cyclone's final landfall, widespread evacuations occurred across southeastern Yemen, including in areas controlled by al-Qaeda, amid the country's ongoing civil war. Early on 3 November, the storm made landfall near Mukalla, Yemen, as a very severe cyclonic storm and the strongest storm on record to strike the nation. Chapala weakened into a remnant low the next day over land. Several years' worth of heavy rainfall inundated coastal areas, damaging roads and hundreds of homes. Eight people died in Yemen, a low total credited to the evacuations, and another 65 were injured. After cyclones Chapala and Megh, several countries, non-government organizations, and agencies within the United Nations provided monetary and material assistance to Yemen. The country faced food and fuel shortages, and residual storm effects contributed to an outbreak of locusts and dengue fever, the latter of which killed seven people.- A dwarf planet is a planetary-mass object that does not dominate its region of space (as a true or classical planet does) and is not a satellite. That is, it is in direct orbit of the Sun and is massive enough to be plastic – for its gravity to maintain it in a hydrostatically equilibrious shape (usually a spheroid) – but has not cleared the neighborhood of its orbit of similar objects. The prototype dwarf planet is Pluto. The interest of dwarf planets to planetary geologists is that, being possibly differentiated and geologically active bodies, they may display planetary geology, an expectation borne out by the 2015 New Horizons mission to Pluto.
The number of dwarf planets in the Solar System is unknown. This is because determining whether a body is in hydrostatic equilibrium requires close observation by spacecraft. The half-dozen largest candidates have either been visited by spacecraft (Pluto and Ceres) or have at least one known moon (Pluto, Eris, Haumea, Makemake, Gonggong, Quaoar), which allows their masses and thus an estimate of their densities to be determined. Mass and density in turn can be fit into models of hydrostatic equilibrium.
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Gallium (IPA: /ˈgaliəm/) is a chemical element that has the symbol Ga and atomic number 31. A rare, soft silvery metallic poor metal, gallium is a brittle solid at low temperatures but liquefies slightly above room temperature and will melt in the hand. It occurs in trace amounts in bauxite and zinc ores. An important application is in the compound gallium arsenide, used as a semiconductor, most notably in light-emitting diodes (LEDs).
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Did you know...
- ...that Scientists and Engineers for America is an organization focused on promoting sound science in government, and backing political candidates who support science and its applications?
- ...that the 2004 Christmas Eve Snowstorm was the most significant snow event for South Texas since 1895?
- ...that Stanford professor Kate Lorig developed a peer-led chronic disease self management course which is the basis of the Expert Patient Programme of the British National Health Service?
- ...that walking fish can actually skip, crawl, slither, and even climb trees?
- ...that the Thanksgiving 1984 Nor'easter deposited a 197-foot Venezuelan freighter in the backyard of a Palm Beach, Florida socialite, where it remained for several months?
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- ^ "Atlantic hurricane best track (HURDAT version 2)" (Database). United States National Hurricane Center. May 25, 2020.