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🔗 Russia 🔗 Disaster management 🔗 Terrorism 🔗 Russia/politics and law of Russia 🔗 Russia/history of Russia

The Russian apartment bombings were a series of explosions that hit four apartment blocks in the Russian cities of Buynaksk, Moscow and Volgodonsk in September 1999, killing more than 300, injuring more than 1000, and spreading a wave of fear across the country. The bombings, together with the Invasion of Dagestan, triggered the Second Chechen War. Then-prime minister Vladimir Putin's handling of the crisis boosted his popularity greatly and helped him attain the presidency within a few months. Russian courts ruled that the attacks were orchestrated by Chechen-linked militants, while some scholars, journalists, and politicians have argued that Russian security services likely organized the bombings.

The blasts hit Buynaksk on 4 September and in Moscow on 9 and 13 September. On 13 September, Russian Duma speaker Gennadiy Seleznyov made an announcement in the Duma about receiving a report that another bombing had just happened in the city of Volgodonsk. A bombing did indeed happen in Volgodonsk, but only three days later, on 16 September. Chechen militants were blamed for the bombings, but denied responsibility, along with Chechen president Aslan Maskhadov.

A suspicious device resembling those used in the bombings was found and defused in an apartment block in the Russian city of Ryazan on 22 September. On 23 September, Vladimir Putin praised the vigilance of the inhabitants of Ryazan and ordered the air bombing of Grozny, which marked the beginning of the Second Chechen War. Three FSB agents who had planted the devices at Ryazan were arrested by the local police. On 24 September 1999, head of FSB Nikolay Patrushev announced that the incident in Ryazan had been an anti-terror drill and the device found there contained only sugar.

The official Russian investigation of the Buynaksk bombing was completed in 2000, while the investigation of Moscow and Volgodonsk bombings was completed in 2002. In 2000, seven people were convicted of perpetrating the Buinaksk attack. According to the court ruling on the Moscow and Volgodonsk bombings, which was announced in 2004, the attacks were organised and led by Achemez Gochiyaev, who remains at large. All bombings, the court ruled, were ordered by Islamist warlords Ibn Al-Khattab and Abu Omar al-Saif, who have been killed. Five other suspects have been killed and six have been convicted by Russian courts on terrorism-related charges.

Parliament member Yuri Shchekochikhin filed two motions for a parliamentary investigation of the events, but the motions were rejected by the Russian Duma in March 2000. An independent public commission to investigate the bombings was chaired by Duma deputy Sergei Kovalev. The commission was rendered ineffective because of government refusal to respond to its inquiries. Two key members of the Kovalev Commission, Sergei Yushenkov and Yuri Shchekochikhin, have since died in apparent assassinations. The Commission’s lawyer and investigator Mikhail Trepashkin was arrested and served four years in prison for revealing state secrets. Former FSB agent Alexander Litvinenko, who defected and blamed the FSB for the bombings, was poisoned and killed in London in 2006. A British inquiry later determined that Litvinenko's murder was "probably" carried out with the approval of Putin and Patrushev.

The 1999 attacks were officially attributed to Chechen terrorists. According to some historians and journalists, the bombings were coordinated by the Russian state security services to bring Putin into the presidency. Others disagree with such theories. Independent investigations have faced obstruction from Russian security services, raising further suspicions about their involvement in the attacks.

🔗 Biography 🔗 Lists 🔗 Ethnic groups 🔗 Jewish history 🔗 Israel 🔗 Jewish culture 🔗 Awards

Nobel Prizes have been awarded to over 900 individuals, of whom at least 20% were Jews although the Jewish population comprises less than 0.2% of the world's population. Various theories have been proposed to explain this phenomenon, which has received considerable attention. Israeli academics Dr. Elay Ben-Gal and Professor Yeshayahu Leibowitz, curious about the phenomenon, started to form an encyclopedia of Jewish Nobel laureates and interview as many as possible about their life and work.

Jews have been recipients of all six awards. The first Jewish recipient, Adolf von Baeyer, was awarded the prize in Chemistry in 1905. As of 2019, the most recent Jewish recipient was economics laureate Michael Kremer.

Jewish laureates Elie Wiesel and Imre Kertész survived the extermination camps during the Holocaust, while François Englert survived by being hidden in orphanages and children's homes. Others, such as Walter Kohn, Otto Stern, Albert Einstein, Hans Krebs and Martin Karplus had to flee Nazi Germany to avoid persecution. Still others, including Rita Levi-Montalcini, Herbert Hauptman, Robert Furchgott, Arthur Kornberg, and Jerome Karle experienced significant antisemitism in their careers.

Arthur Ashkin, a 96-year-old American Jew was, at the time of his award, the oldest person to receive a Nobel Prize.

🔗 Ancient Near East 🔗 Ancient Egypt 🔗 Assyria 🔗 Iraq 🔗 Writing systems 🔗 Archaeology 🔗 Phoenicia

The Amarna letters (; sometimes referred to as the Amarna correspondence or Amarna tablets, and cited with the abbreviation EA, for "El Amarna") are an archive, written on clay tablets, primarily consisting of diplomatic correspondence between the Egyptian administration and its representatives in Canaan and Amurru, or neighboring kingdom leaders, during the New Kingdom, spanning a period of no more than thirty years between c. 1360–1332 BC (see here for dates). The letters were found in Upper Egypt at el-Amarna, the modern name for the ancient Egyptian capital of Akhetaten, founded by pharaoh Akhenaten (1350s–1330s BC) during the Eighteenth Dynasty of Egypt. The Amarna letters are unusual in Egyptological research, because they are written not in the language of ancient Egypt, but in cuneiform, the writing system of ancient Mesopotamia. Most are in a variety of Akkadian sometimes characterised as a mixed language, Canaanite-Akkadian; one especially long letter—abbreviated EA 24—was written in a late dialect of Hurrian, and is the longest contiguous text known to survive in that language.

The known tablets total 382, of which 358 have been published by the Norwegian Assyriologist Jørgen Alexander Knudtzon in his work, Die El-Amarna-Tafeln, which came out in two volumes (1907 and 1915) and remains the standard edition to this day. The texts of the remaining 24 complete or fragmentary tablets excavated since Knudtzon have also been made available.

The Amarna letters are of great significance for biblical studies as well as Semitic linguistics because they shed light on the culture and language of the Canaanite peoples in this time period. Though most are written in Akkadian, the Akkadian of the letters is heavily colored by the mother tongue of their writers, who probably spoke an early form of Proto-Canaanite, the language(s) which would later evolve into the daughter languages of Hebrew and Phoenician. These "Canaanisms" provide valuable insights into the proto-stage of those languages several centuries prior to their first actual manifestation.

🔗 Business 🔗 Psychology

Theory X and Theory Y are theories of human work motivation and management. They were created by Douglas McGregor while he was working at the MIT Sloan School of Management in the 1950s, and developed further in the 1960s. McGregor's work was rooted in motivation theory alongside the works of Abraham Maslow, who created the hierarchy of needs. The two theories proposed by McGregor describe contrasting models of workforce motivation applied by managers in human resource management, organizational behavior, organizational communication and organizational development. Theory X explains the importance of heightened supervision, external rewards, and penalties, while Theory Y highlights the motivating role of job satisfaction and encourages workers to approach tasks without direct supervision. Management use of Theory X and Theory Y can affect employee motivation and productivity in different ways, and managers may choose to implement strategies from both theories into their practices.

🔗 Europe 🔗 Musical Instruments 🔗 Percussion

A pyrophone, also known as a "fire/explosion organ" or "fire/explosion calliope" is a musical instrument in which notes are sounded by explosions, or similar forms of rapid combustion, rapid heating, or the like, such as burners in cylindrical glass tubes, creating light and sound. It was invented by physicist and musician Georges Frédéric Eugène Kastner (born 1852 in Strasbourg, France – died 1882 in Bonn, Germany), son of composer Jean-Georges Kastner, around 1870.

🔗 Iran 🔗 Architecture 🔗 Food and drink

Yakhchāl (Persian: یخچال‎ "ice pit"; yakh meaning "ice" and chāl meaning "pit") is an ancient type of evaporative cooler. Above ground, the structure had a domed shape, but had a subterranean storage space. It was often used to store ice, but sometimes was used to store food as well. The subterranean space coupled with the thick heat-resistant construction material insulated the storage space year round. These structures were mainly built and used in Persia. Many that were built hundreds of years ago remain standing.

🔗 Chess

El Ajedrecista (English: The Chess Player) is an automaton built in 1912 by Leonardo Torres y Quevedo, one of the first autonomous machines capable of playing chess. As opposed to the human-operated The Turk and Ajeeb, El Ajedrecista was a true automaton built to play chess without human guidance. It played an endgame with three chess pieces, automatically moving a white king and a rook to checkmate the black king moved by a human opponent.

The device could be considered the first computer game in history. It created great excitement when it made its debut, at the University of Paris in 1914. It was first widely mentioned in Scientific American as "Torres and His Remarkable Automatic Devices" on November 6, 1915.

The automaton does not deliver checkmate in the minimum number of moves, nor always within the 50 moves allotted by the fifty-move rule, because of the simple algorithm that calculates the moves. It did, however, checkmate the opponent every time. If an illegal move was made by the opposite player, the automaton would signal it by turning on a light. If the opposing player made three illegal moves, the automaton would stop playing.

🔗 Internet culture 🔗 Linguistics 🔗 Numismatics 🔗 Cryptocurrency

Hodl ( HOD-əl; often written HODL) is slang in the cryptocurrency community for holding the cryptocurrency rather than selling it. A person who does this is known as a Hodler. It originated in a December 2013 post on the Bitcoin Forum message board by an apparently inebriated user who posted with a typo in the subject, "I AM HODLING." It is often backronymed to "hold on for dear life". In 2017, Quartz listed it as one of the essential slang terms in Bitcoin culture, and described it as a stance, "to stay invested in bitcoin and not to capitulate in the face of plunging prices." TheStreet.com referred to it as the "favorite mantra" of Bitcoin holders. Bloomberg News referred to it as a "mantra" for holders during market routs.

🔗 Computing 🔗 Computer science 🔗 Cryptography 🔗 Cryptography/Computer science

Diffie–Hellman key exchange is a method of securely exchanging cryptographic keys over a public channel and was one of the first public-key protocols as conceived by Ralph Merkle and named after Whitfield Diffie and Martin Hellman. DH is one of the earliest practical examples of public key exchange implemented within the field of cryptography.

Traditionally, secure encrypted communication between two parties required that they first exchange keys by some secure physical means, such as paper key lists transported by a trusted courier. The Diffie–Hellman key exchange method allows two parties that have no prior knowledge of each other to jointly establish a shared secret key over an insecure channel. This key can then be used to encrypt subsequent communications using a symmetric key cipher.

Diffie–Hellman is used to secure a variety of Internet services. However, research published in October 2015 suggests that the parameters in use for many DH Internet applications at that time are not strong enough to prevent compromise by very well-funded attackers, such as the security services of large governments.

The scheme was published by Whitfield Diffie and Martin Hellman in 1976, but in 1997 it was revealed that James H. Ellis, Clifford Cocks, and Malcolm J. Williamson of GCHQ, the British signals intelligence agency, had previously shown in 1969 how public-key cryptography could be achieved.

Although Diffie–Hellman key agreement itself is a non-authenticated key-agreement protocol, it provides the basis for a variety of authenticated protocols, and is used to provide forward secrecy in Transport Layer Security's ephemeral modes (referred to as EDH or DHE depending on the cipher suite).

The method was followed shortly afterwards by RSA, an implementation of public-key cryptography using asymmetric algorithms.

Expired U.S. Patent 4,200,770 from 1977 describes the now public-domain algorithm. It credits Hellman, Diffie, and Merkle as inventors.

🔗 Mathematics

Modern Arabic mathematical notation is a mathematical notation based on the Arabic script, used especially at pre-university levels of education. Its form is mostly derived from Western notation, but has some notable features that set it apart from its Western counterpart. The most remarkable of those features is the fact that it is written from right to left following the normal direction of the Arabic script. Other differences include the replacement of the Greek and Latin alphabet letters for symbols with Arabic letters and the use of Arabic names for functions and relations.