Have a deep view into what people are curious about.

🔗 Books 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Visual arts

The Black Hours, MS M.493 (or the Morgan Black Hours) is an illuminated book of hours completed in Bruges between 1460 and 1475. It consists of 121 pages (leaves), with Latin text written in Gothic minuscule script. The words are arranged in rows of fourteen lines and follow the Roman version of the texts. The lettering is inscribed in silver and gold and placed within borders ornamented with flowers, foliage and grotesques, on pages dyed a deep blueish black. It contains fourteen full-page miniatures and opens with the months of the liturgical calendar (folios 3 verso – 14 recto), followed by the Hours of the Virgin, and ends with the Office of the Dead (folio 121v).

MS M.493 has been in the collection of the Morgan Library & Museum, New York, since 1912. It is one of seven surviving black books of hours, all originating from Bruges and dated to the mid-to-late 15th century. They are so named for their unusual dark blueish appearance, a colourisation achieved through the expensive process of dyeing the vellum with iron gall ink. This dye is very corrosive and the surviving examples are mostly badly decomposed; MS M.493 is in relatively good condition due to its very thick parchment.

The book is a masterpiece of Late Gothic manuscript illumination. However, no records survive of its commission, but its uniquely dark tone, expense of production, quality and rarity suggest ownership by privileged and sophisticated members of the Burgundian court. The book is often attributed, on stylistic grounds, to a follower of Willem Vrelant, a leading and influential Flemish illuminator.

🔗 Mathematics

Zero to the power of zero, denoted by 0⁰, is a mathematical expression with no agreed-upon value. The most common possibilities are 1 or leaving the expression undefined, with justifications existing for each, depending on context. In algebra and combinatorics, the generally agreed upon value is 0⁰ = 1, whereas in mathematical analysis, the expression is sometimes left undefined. Computer programs also have differing ways of handling this expression.

🔗 Germany 🔗 Military history 🔗 Crime 🔗 Politics 🔗 Guild of Copy Editors 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Politics/Fascism 🔗 Military history/European military history

From 1933 to the end of the Second World War, high-ranking officers of the Armed Forces of Nazi Germany accepted vast bribes in the form of cash, estates, and tax exemptions in exchange for their loyalty to Nazism. Unlike bribery at lower ranks in the Wehrmacht, which was also widespread, these payments were regularized, technically legal and made with the full knowledge and consent of the leading Nazi figures.

🔗 Aviation 🔗 Aviation/gliding

Dynamic soaring is a flying technique used to gain energy by repeatedly crossing the boundary between air masses of different velocity. Such zones of wind gradient are generally found close to obstacles and close to the surface, so the technique is mainly of use to birds and operators of radio-controlled gliders, but glider pilots are sometimes able to soar dynamically in meteorological wind shears at higher altitudes.

Dynamic soaring is sometimes confused with slope soaring which is a technique for achieving elevation.

🔗 Russia 🔗 Russia/technology and engineering in Russia 🔗 Spaceflight 🔗 Russia/science and education in Russia 🔗 Russia/history of Russia

Soyuz 11 (Russian: Союз 11, Union 11) was the only crewed mission to board the world's first space station, Salyut 1 (Soyuz 10 had soft-docked but had not been able to enter due to latching problems). The crew, Georgy Dobrovolsky, Vladislav Volkov, and Viktor Patsayev, arrived at the space station on 7 June 1971 and departed on 29 June. The mission ended in disaster when the crew capsule depressurized during preparations for reentry, killing the three-man crew. The three crew members of Soyuz 11 are the only humans known to have died in space.

🔗 Computing 🔗 Computer graphics

The Stanford bunny is a computer graphics 3D test model developed by Greg Turk and Marc Levoy in 1994 at Stanford University. The model consists of 69,451 triangles, with the data determined by 3D scanning a ceramic figurine of a rabbit. This figurine and others were scanned to test methods of range scanning physical objects.

The data can be used to test various graphics algorithms, including polygonal simplification, compression, and surface smoothing. There are a few complications with this dataset that can occur in any 3D scan data: the model is manifold connected and has holes in the data, some due to scanning limits and some due to the object being hollow. These complications provide a more realistic input for any algorithm that is benchmarked with the Stanford bunny, though by today's standards, in terms of geometric complexity and triangle count, it is considered a simple model.

The model was originally available in .ply (polygons) file format with 4 different resolutions.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Aviation/aircraft 🔗 Military history/Maritime warfare 🔗 Military history/Russian, Soviet and CIS military history 🔗 Aviation/Soviet aviation

The Lun-class ekranoplan is a ground effect vehicle (GEV) designed by Rostislav Evgenievich Alexeyev in 1975 and used by the Soviet and Russian navies from 1987 until sometime in the late 1990s.

It flew using the lift generated by the ground effect of its large wings when within about four metres (13 ft) above the surface of the water. Although they might look similar to regular aircraft, and have related technical characteristics, ekranoplans like the Lun are not aircraft, seaplanes, hovercraft, nor hydrofoils. Rather, "ground effect" is a distinct technology. The International Maritime Organization classifies these vehicles as maritime ships.

The name Lun comes from the Russian word for harrier.

🔗 Disability 🔗 Writing systems

English Braille, also known as Grade 2 Braille, is the braille alphabet used for English. It consists of around 250 letters (phonograms), numerals, punctuation, formatting marks, contractions, and abbreviations (logograms). Some English Braille letters, such as ⠿ ⟨for⟩, correspond to more than one letter in print.

There are three levels of complexity in English Braille. Grade 1 is a nearly one-to-one transcription of printed English and is restricted to basic literacy. Grade 2, which is nearly universal beyond basic literacy materials, abandons one-to-one transcription in many places (such as the letter ⠿ ⟨for⟩) and adds hundreds of abbreviations and contractions. Both Grade 1 and Grade 2 have been standardized. "Grade 3" is any of various personal shorthands that are almost never found in publications. Most of this article describes the 1994 American edition of Grade 2 Braille, which is largely equivalent to British Grade 2 Braille. Some of the differences with Unified English Braille, which was officially adopted by various countries between 2005 and 2012, are discussed at the end.

Braille is frequently portrayed as a re-encoding of the English orthography used by sighted people. However, braille is a separate writing system, not a variant of the printed English alphabet.

🔗 United States 🔗 Biography

William Robert Sutherland (May 10, 1936 – February 18, 2020) was an American computer scientist who was the longtime manager of three prominent research laboratories, including Sun Microsystems Laboratories (1992–1998), the Systems Science Laboratory at Xerox PARC (1975–1981), and the Computer Science Division of Bolt, Beranek and Newman, Inc. which helped develop the ARPANET.

In these roles, Sutherland participated in the creation of the personal computer, the technology of advanced microprocessors, the Smalltalk programming language, the Java programming language and the Internet.

Unlike traditional corporate research managers, Sutherland added individuals from fields like psychology, cognitive science, and anthropology to enhance the work of his technology staff. He also directed his scientists to take their research, like the Xerox Alto "personal" computer, outside of the laboratory to allow people to use it in a corporate setting and to observe their interaction with it.

In addition, Sutherland fostered a collaboration between the researchers at California Institute of Technology developing techniques of very large scale integrated circuits (VLSI) — his brother Ivan and Carver Mead — and Lynn Conway of his PARC staff. With PARC resources made available by Sutherland, Mead and Conway developed a textbook and university syllabus that helped expedite the development and distribution of a technology whose effect is now immeasurable.

Sutherland said that a research lab is primarily a teaching institution, "teaching whatever is new so that the new can become familiar, old, and used widely."

Sutherland was born in Hastings, Nebraska on May 10, 1936, to a father from New Zealand; his mother was from Scotland. The family moved to Wilmette, Illinois, then Scarsdale, New York, for his father's career. Bert Sutherland graduated from Scarsdale High School, then received his bachelor's degree in electrical engineering from Rensselaer Polytechnic Institute (RPI), and his master's degree and Ph.D. from Massachusetts Institute of Technology (MIT); his thesis advisor was Claude Shannon. During his military service in the United States Navy, he was awarded the Legion of Merit as a Carrier ASW plane commander. He was the older brother of Ivan Sutherland. Bert Sutherland died on February 18, 2020, aged 83.

🔗 Medicine 🔗 Mexico

The cocoliztli epidemic or the great pestilence is a term given to millions of deaths in the territory of New Spain in present-day Mexico in the 16th century attributed to one or more illnesses collectively called cocoliztli, a mysterious illness characterized by high fevers and bleeding. It ravaged the Mexican highlands in epidemic proportions. The disease became known as Cocoliztli by the native Aztecs, and had devastating effects on the area’s demography, particularly for the indigenous people. Based on the death toll, this outbreak is often referred to as the worst disease epidemic in the history of Mexico. Subsequent outbreaks continued to baffle both Spanish and native doctors, with little consensus among modern researchers on the pathogenesis. However, recent bacterial genomic studies have suggested that Salmonella, specifically a serotype of Salmonella enterica known as Paratyphi C, was at least partially responsible for this initial outbreak. It might have also been an indigenous viral hemorrhagic fever, perhaps exacerbated by the worst droughts to affect that region in 500 years, as well as living conditions for indigenous peoples of Mexico in the wake of the Spanish conquest (c. 1519).