Portal:Science
Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into two or three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; and the behavioural sciences (e.g., economics, psychology, and sociology), which study individuals and societies. The formal sciences (e.g., logic, mathematics, and theoretical computer science), which study formal systems governed by axioms and rules, are sometimes described as being sciences as well; however, they are often regarded as a separate field because they rely on deductive reasoning instead of the scientific method or empirical evidence as their main methodology. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as engineering and medicine. (Full article...)
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The Acra (also spelled Akra, from Ancient Greek: Ἄκρα, Hebrew: חקרא ,חקרה Ḥaqra(h)), with the meaning of "stronghold" (see under "Etymology"), was a place in Jerusalem thought to have had a fortified compound built by Antiochus Epiphanes, ruler of the Seleucid Empire, following his sack of the city in 168 BCE. The name Acra was also used at a later time for a city quarter probably associated with the by-then destroyed fortress, known in his time to Josephus (1st century CE) as both Acra and "the lower city". The fortress played a significant role in the events surrounding the Maccabean Revolt, which resulted in the formation of the Hasmonean Kingdom. The "upper city" was captured by Judas Maccabeus, with the Seleucid garrison taking refuge in the "Acra" below, and the task of destroying this last enemy stronghold inside Jerusalem fell to Simon Maccabeus surnamed Thassi. Knowledge about the Acra is based almost exclusively on the writings of Josephus, which are of a later date, and on the First and Second Books of Maccabees, which were written not long after the described events. (Full article...)
Russula virescens is a basidiomycete mushroom of the genus Russula, and is commonly known as the green-cracking russula, the quilted green russula, or the green brittlegill. It can be recognized by its distinctive pale green cap that measures up to 15 cm (6 in) in diameter, the surface of which is covered with darker green angular patches. It has crowded white gills, and a firm, white stipe that is up to 8 cm (3 in) tall and 4 cm (1.6 in) thick. Considered to be one of the best edible mushrooms of the genus Russula, it is especially popular in Spain and China. With a taste that is described variously as mild, nutty, fruity, or sweet, it is cooked by grilling, frying, sautéeing, or eaten raw. Mushrooms are rich in carbohydrates and proteins, with a low fat content. (Full article...)
Banksia attenuata, commonly known as the candlestick banksia, slender banksia, or biara to the Noongar people, is a species of plant in the family Proteaceae. Commonly a tree, it reaches 10 m (33 ft) high, but it is often a shrub in drier areas 0.4 to 2 m (1.3 to 6.6 ft) high. It has long, narrow, serrated leaves and bright yellow inflorescences, or flower spikes, held above the foliage, which appear in spring and summer. The flower spikes age to grey and swell with the development of the woody follicles. The candlestick banksia is found across much of the southwest of Western Australia, from north of Kalbarri National Park down to Cape Leeuwin and across to Fitzgerald River National Park. (Full article...)
Gertie the Dinosaur is a 1914 animated short film by American cartoonist and animator Winsor McCay. It is the earliest animated film to feature a dinosaur. McCay first used the film before live audiences as an interactive part of his vaudeville act; the frisky, childlike Gertie did tricks at the command of her master. McCay's employer William Randolph Hearst curtailed McCay's vaudeville activities, so McCay added a live-action introductory sequence to the film for its theatrical release renamed Winsor McCay, the Famous Cartoonist, and Gertie. McCay abandoned a sequel, Gertie on Tour (c. 1921), after producing about a minute of footage. (Full article...)
The Zapata rail (Mustelirallus cerverai) is a medium-sized, dark-coloured rail. It has brown upperparts, greyish-blue underparts, a red-based yellow bill, white undertail coverts, and red eyes and legs. Its short wings render it almost flightless. It is endemic to the wetlands of the Zapata Peninsula in southern Cuba, where its only known nest was found in sawgrass tussocks. Little is known of its diet or reproductive behaviour, and its described calls may belong to a different species. (Full article...)