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🔗 Biography 🔗 Biography/science and academia 🔗 Egypt

Taqi al-Din Muhammad ibn Ma'ruf ash-Shami al-Asadi (Arabic: تقي الدين محمد بن معروف الشامي‎, Ottoman Turkish: تقي الدين محمد بن معروف الشامي السعدي‎, Turkish: Takiyüddin) (1526-1585) was an Ottoman polymath active in Cairo and Istanbul. He was the author of more than ninety books on a wide variety of subjects, including astronomy, clocks, engineering, mathematics, mechanics, optics and natural philosophy.

In 1574 the Ottoman Sultan Murad III invited Taqī ad-Dīn to build the Constantinople observatory. Using his exceptional knowledge in the mechanical arts, Taqī ad-Dīn constructed instruments like huge armillary and mechanical clocks that he used in his observations of the Great Comet of 1577. He also used European celestial and terrestrial globes that were delivered to Istanbul in gift-exchange.

The major work that resulted from his work in the observatory is titled "The tree of ultimate knowledge [in the end of time or the world] in the Kingdom of the Revolving Spheres: The astronomical tables of the King of Kings [Murād III]" (Sidrat al-muntah al-afkar fi malkūt al-falak al-dawār– al-zij al-Shāhinshāhi). The work was prepared according to the results of the observations carried out in Egypt and Istanbul in order to correct and complete Ulugh Beg's Zij as-Sultani. The first 40 pages of the work deal with calculations, followed by discussions of astronomical clocks, heavenly circles, and information about three eclipses which he observed at Cairo and Istanbul. For corroborating data of other observations of eclipses in other locales like Daud ar-Riyyadi (David the Mathematician), David Ben-Shushan of Salonika.

As a polymath, Taqī al-Dīn wrote numerous books on astronomy, mathematics, mechanics, and theology. His method of finding coordinates of stars were reportedly so precise that he got better measurements than his contemporaries, Tycho Brahe and Nicolas Copernicus. Brahe is also thought to have been aware of al-Dīn's work.

Taqī Ad-Dīn also described a steam turbine with the practical application of rotating a spit in 1551. He worked on and created astronomical clocks for his observatory. Taqī Ad-Dīn also wrote a book on optics, in which he determined the light emitted from objects, proved the Law of Reflection observationally, and worked on refraction.

🔗 Mathematics

In geometric topology, the Clifford torus is the simplest and most symmetric flat embedding of the cartesian product of two circles S¹_a and S¹_b (in the same sense that the surface of a cylinder is "flat"). It is named after William Kingdon Clifford. It resides in R⁴, as opposed to in R³. To see why R⁴ is necessary, note that if S¹_a and S¹_b each exist in their own independent embedding spaces R²_a and R²_b, the resulting product space will be R⁴ rather than R³. The historically popular view that the cartesian product of two circles is an R³ torus in contrast requires the highly asymmetric application of a rotation operator to the second circle, since that circle will only have one independent axis z available to it after the first circle consumes x and y.

Stated another way, a torus embedded in R³ is an asymmetric reduced-dimension projection of the maximally symmetric Clifford torus embedded in R⁴. The relationship is similar to that of projecting the edges of a cube onto a sheet of paper. Such a projection creates a lower-dimensional image that accurately captures the connectivity of the cube edges, but also requires the arbitrary selection and removal of one of the three fully symmetric and interchangeable axes of the cube.

If S¹_a and S¹_b each has a radius of ${\displaystyle \textstyle {\sqrt {1/2}}}$, their Clifford torus product will fit perfectly within the unit 3-sphere S³, which is a 3-dimensional submanifold of R⁴. When mathematically convenient, the Clifford torus can be viewed as residing inside the complex coordinate space C², since C² is topologically equivalent to R⁴.

The Clifford torus is an example of a square torus, because it is isometric to a square with opposite sides identified. It is further known as a Euclidean 2-torus (the "2" is its topological dimension); figures drawn on it obey Euclidean geometry as if it were flat, whereas the surface of a common "doughnut"-shaped torus is positively curved on the outer rim and negatively curved on the inner. Although having a different geometry than the standard embedding of a torus in three-dimensional Euclidean space, the square torus can also be embedded into three-dimensional space, by the Nash embedding theorem; one possible embedding modifies the standard torus by a fractal set of ripples running in two perpendicular directions along the surface.

The Cybiko is a Russian handheld computer introduced in the United States by David Yang's company Cybiko Inc. as a retail test market in New York on April 2000, and rolled out nationwide in May 2000. It is designed for teens, featuring its own two-way radio text messaging system. It had over 430 "official" freeware games and applications. Because of the text messaging system, it features a rubber QWERTY keyboard. An MP3 player add-on with a SmartMedia card slot was made for the unit as well. The company stopped manufacturing the units after two product versions and only a few years on the market. Cybikos can communicate with each other up to a maximum range of 100 metres (300 feet). Several Cybikos can chat with each other in a wireless chatroom. By the end of 2000, the Cybiko Classic sold over 500,000 units.

🔗 Plants

Lithops is a genus of succulent plants in the ice plant family, Aizoaceae. Members of the genus are native to southern Africa. The name is derived from the Ancient Greek words λίθος (líthos), meaning "stone," and ὄψ (óps), meaning "face," referring to the stone-like appearance of the plants. They avoid being eaten by blending in with surrounding rocks and are often known as pebble plants or living stones. The formation of the name from the Ancient Greek "-ops" means that even a single plant is called a Lithops.

🔗 Physics 🔗 Soil

The angle of repose, or critical angle of repose, of a granular material is the steepest angle of descent or dip relative to the horizontal plane to which a material can be piled without slumping. At this angle, the material on the slope face is on the verge of sliding. The angle of repose can range from 0° to 90°. The morphology of the material affects the angle of repose; smooth, rounded sand grains cannot be piled as steeply as can rough, interlocking sands. The angle of repose can also be affected by additions of solvents. If a small amount of water is able to bridge the gaps between particles, electrostatic attraction of the water to mineral surfaces will increase the angle of repose, and related quantities such as the soil strength.

When bulk granular materials are poured onto a horizontal surface, a conical pile will form. The internal angle between the surface of the pile and the horizontal surface is known as the angle of repose and is related to the density, surface area and shapes of the particles, and the coefficient of friction of the material. Material with a low angle of repose forms flatter piles than material with a high angle of repose.

The term has a related usage in mechanics, where it refers to the maximum angle at which an object can rest on an inclined plane without sliding down. This angle is equal to the arctangent of the coefficient of static friction μ_s between the surfaces.

🔗 Brands 🔗 Automobiles 🔗 Japan 🔗 Japan/Car

The Toyota Century (Japanese: トヨタ・センチュリー, Hepburn: Toyota Senchurī) is a limousine produced mainly for the Japanese market, serving as Toyota's flagship car within Japan; globally the unrelated Lexus LS series is Toyota's flagship luxury model. Production of the Century began in 1967, and the model received only minor changes until redesigns in 1997 and 2018.

The Century derived its name from the 100th birthday of Sakichi Toyoda (born 14 February 1867), the founder of Toyota Industries. It is often used by the Imperial House of Japan, the Prime Minister of Japan, senior Japanese government leaders, and high-level executive businessmen. The Century is comparable in purpose to the Austin Princess/Daimler DS420, Cadillac Series 70, Mercedes-Benz 600 series, Chinese Red Flag, Rolls-Royce, and Russian ZIS/ZIL limousines.

The first-generation Century was available with only a V8 engine (the third post-war Japanese-built sedan so-equipped) at its introduction in 1967 until a full platform redesign in 1997. The second generation was only installed with a Toyota-designed and -built V12, an engine bespoke to the Century, until 2018, when the power-train reverted to a V8 with the addition of Toyota's hybrid technology.

While the Century is a premium, full-size luxury sedan, it is not available at Japanese Lexus dealerships; it can only be purchased at specifically identified Toyota Store locations. The gold phoenix logo used throughout is called the Hō'ō (鳳凰) or Fushichō (不死鳥) from Sinospheric mythology, representing the Imperial House of Japan, and the image can be found throughout Asia, such as the Kinkaku-ji in Kyoto.

The exterior styling of the Century has, with some modifications, remained unchanged since its introduction, primarily due to its perception as denoting conservative success. Its appearance is iconic in Asian countries and is usually painted black. The closest Japanese competitor was the Nissan President, with a similar status reputation although, during the 1960s and '70s, the high market positioning was also shared with the Mitsubishi Debonair. In the 1970s, two other Japanese competitors introduced large sedans — the Isuzu Statesman de Ville and the Mazda Roadpacer (both derived from General Motors-Australia products) — which were short-lived.

🔗 Medicine 🔗 Medicine/Neurology

Type 3 diabetes is a proposed term to describe the interlinked association between type 1 and type 2 diabetes, and Alzheimer's disease. This term is used to look into potential triggers of Alzheimer's disease in people with diabetes.

The proposed progression from diabetes to Alzheimer's disease is inadequately understood; however there are a number of hypotheses describing potential links between the two diseases. The internal mechanism of Insulin resistance and other metabolic risk factors such as hyperglycaemia, caused by oxidative stress and lipid peroxidation are common processes thought to be contributors to the development of Alzheimer's disease in diabetics.

Diagnosis for this disease is different between patients with type 1 and type 2 diabetes. Type 1 diabetes is usually discovered in children and adolescence while type 2 diabetic patients are often diagnosed later in life. While Type 3 diabetes is not a diagnosis in itself, a diagnosis of suspected Alzheimer's disease can be established through observational signs and sometimes with neuroimaging techniques such as Magnetic Resonance Imaging (MRI) to observe abnormalities in diabetic patient's brain tissue.

The techniques used to prevent the disease in patients with diabetes are similar to individuals who do not show signs of the disease. The four pillars of Alzheimer's disease prevention is currently used as a guide for individuals of whom are at risk of developing Alzheimer's disease.

Research into the effectiveness of Glucagon-like Peptide 1 and Melatonin administration to manage the progression of Alzheimer's disease in diabetic patients is currently being conducted to decrease the rate at which Alzheimer's disease progresses.

Labelling Alzheimer's disease as Type 3 Diabetes is generally controversial, and this definition is not a known medical diagnosis. While insulin resistance is a risk factor for the development of Alzheimer's disease and some other dementias, causes of Alzheimer's disease are likely to be much more complex than being explained by insulin factors on their own, and indeed several patients with Alzheimer's disease have normal insulin metabolism.

🔗 Geology 🔗 Geology/Meteorites

Thokcha (Tibetan: ཐོག་ལྕགས, Wylie: thog lcags; also alternatively Tibetan: གནམ་ལྕགས, Wylie: gnam lcags) are tektites and meteorites which serve as amulets. Typically high in iron content, these are traditionally believed to contain a magical, protective power comparable to Tibetan dzi beads. Most thokcha are made of a copper alloy.

The use of meteoric iron has been common throughout the history of ferrous metallurgy. Historically, thokcha were prized for the metallurgical fabrication of weapons, musical instruments, and sacred tools, such as the phurba. Thokcha are an auspicious addition in the metallurgical fabrication of sacred objects cast from panchaloha.

Writer Robert Beer regards meteoric iron as "the supreme substance for forging the physical representation of the vajra or other iron weapons." It was believed that these amulets had been tempered by the celestial gods before falling to Earth. Beer describes the metal falling from space as a metaphor for "the indivisibility of form and emptiness." Many meteorite fragments can be found in Tibet due to its high altitude and open landscape.

🔗 Literature

"Belling the Cat" is a fable also known under the titles "The Bell and the Cat" and "The Mice in Council". Although often attributed to Aesop, it was not recorded before the Middle Ages and has been confused with the quite different fable of Classical origin titled The Cat and the Mice. In the classificatory system established for the fables by B. E. Perry, it is numbered 613, which is reserved for Mediaeval attributions outside the Aesopic canon.

🔗 Military history 🔗 Korea 🔗 Visual arts 🔗 Military history/Asian military history 🔗 Spain 🔗 Military history/Korean military history

Massacre in Korea (French: Massacre en Corée) is an expressionistic painting completed on 18 January 1951 by Pablo Picasso. It is Picasso's third anti-war painting and depicts a scene of a massacre of a group of naked women and children by a firing squad. It has been considered to be a condemnation of American intervention in the Korean War. The painting is exhibited in the Musée Picasso in Paris.