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🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software

The Affero General Public License (Affero GPL and informally Affero License) is a free software license. The first version of the Affero General Public License (AGPLv1), was published by Affero, Inc. in March 2002, and based on the GNU General Public License, version 2 (GPLv2). The second version (AGPLv2) was published in November 2007, as a transitional license to allow an upgrade path from AGPLv1 to the GNU Affero General Public License (a variant of the original Affero GPL license that is compatible with GPLv3).

Both versions of the Affero GPL were designed to close a perceived application service provider (ASP) loophole in the ordinary GPL, where, by using but not distributing the software, the copyleft provisions are not triggered. Each version differs from the version of the GNU GPL on which it is based in having an added provision addressing use of software over a computer network. This provision requires that the full source code be made available to any network user of the AGPL-licensed work, typically a web application.

🔗 Physics

A Bessel beam is a wave whose amplitude is described by a Bessel function of the first kind. Electromagnetic, acoustic, gravitational, and matter waves can all be in the form of Bessel beams. A true Bessel beam is non-diffractive. This means that as it propagates, it does not diffract and spread out; this is in contrast to the usual behavior of light (or sound), which spreads out after being focused down to a small spot. Bessel beams are also self-healing, meaning that the beam can be partially obstructed at one point, but will re-form at a point further down the beam axis.

As with a plane wave, a true Bessel beam cannot be created, as it is unbounded and would require an infinite amount of energy. Reasonably good approximations can be made, however, and these are important in many optical applications because they exhibit little or no diffraction over a limited distance. Approximations to Bessel beams are made in practice either by focusing a Gaussian beam with an axicon lens to generate a Bessel–Gauss beam, by using axisymmetric diffraction gratings, or by placing a narrow annular aperture in the far field. High order Bessel beams can be generated by spiral diffraction gratings.

🔗 Computing 🔗 Computer science

Note G was a computer algorithm written by Ada Lovelace, and was designed to calculate Bernoulli numbers using the hypothetical analytical engine. Note G is generally agreed to be the first algorithm specifically for a computer, and Lovelace is considered as the first computer programmer as a result. The algorithm was the last note in a series labelled A to G, which she employed as visual aids to accompany her English translation of Luigi Menabrea's 1842 French transcription of Charles Babbage's lecture on the analytical engine at the University of Turin, "Notions sur la machine analytique de Charles Babbage" ("Elements of Charles Babbage’s Analytical Machine"). Lovelace's Note G was never tested, as the engine was never built. Her notes, along with her translation, were published in 1843.

In the modern era, thanks to more readily available computing equipment and programming resources, Lovelace's algorithm has since been tested, after being "translated" into modern programming languages. These tests have independently concluded that there was a bug in the script, due to a minor typographical error, rendering the algorithm in its original state unusable.

🔗 India 🔗 Visual arts

Mauryan polish describes one of the frequent characteristics of architecture and sculptures of the Maurya Empire in India (325 to 185 BCE), which gives a very smooth and shiny surface to the stone material, generally of sandstone or granite. Mauryan polish is found especially in the Ashoka Pillars as well as in some constructions like the Barabar Caves. The technique did not end with the empire, but continued to be "used on occasion up to the first or second century A.D.", although the presence of the polish sometimes complicates dating, as with the Didarganj Yakshi. According to the archaeologist John Marshall: the "extraordinary precision and accuracy which characterizes all Mauryan works, and which has never, we venture to say, been surpassed even by the finest workmanship on Athenian buildings".

🔗 United States 🔗 Numismatics 🔗 Numismatics/American currency 🔗 U.S. Congress

The United States Gold Reserve Act of January 30, 1934 required that all gold and gold certificates held by the Federal Reserve be surrendered and vested in the sole title of the United States Department of the Treasury. It also prohibited the Treasury and financial institutions from redeeming dollar bills for gold, established the Exchange Stabilization Fund under control of the Treasury to control the dollar’s value without the assistance (or approval) of the Federal Reserve, and authorized the president to establish the gold value of the dollar by proclamation.

Immediately following passage of the Act, the President, Franklin D. Roosevelt, changed the statutory price of gold from $20.67 per troy ounce to $35. This price change incentivized gold miners globally to expand production and foreigners to export their gold to the United States, while simultaneously devaluing the U.S. dollar by increasing inflation. The increase in gold reserves due to the price change resulted in a large accumulation of gold in the Federal Reserve and U.S. Treasury, much of which was stored in the United States Bullion Depository at Fort Knox and other locations. The increase in gold reserves increased the money supply, lowering real interest rates which in turn increased investment in durable goods.

A year earlier, in 1933, Executive Order 6102 had made it a criminal offense for U.S. citizens to own or trade gold anywhere in the world, with exceptions for some jewelry and collector's coins. These prohibitions were relaxed starting in 1964 – gold certificates were again allowed for private investors on April 24, 1964, although the obligation to pay the certificate holder on demand in gold specie would not be honored. By 1975 Americans could again freely own and trade gold.

🔗 Psychology 🔗 Neuroscience 🔗 Physiology 🔗 Physiology/neuro

An amygdala hijack refers to a personal, emotional response that is immediate, overwhelming, and out of measure with the actual stimulus because it has triggered a much more significant emotional threat. The term was coined by Daniel Goleman in his 1996 book Emotional Intelligence: Why It Can Matter More Than IQ.

🔗 Books

The No Asshole Rule: Building a Civilized Workplace and Surviving One That Isn't is a book by Stanford professor Robert I. Sutton. He initially wrote an essay for the Harvard Business Review, published in the breakthrough ideas for 2004. Following the essay, he received more than one thousand emails and testimonies. Among other reasons disclosed in another article published at the Harvard Business Review, these letters led him to write the book, sell more than 115,000 copies, and win the Quill Award for best business book in 2007.

The theme of this book is that workplace bullying worsens morale and productivity. To screen out the toxic staff, it suggests the "no asshole rule". The author insists upon use of the word asshole since other words such as bully or jerk "do not convey the same degree of awfulness". In terms of using the word in the book's title, he said "There's an emotional reaction to a dirty title. You have a choice between being offensive and being ignored."

🔗 Religion 🔗 Islam 🔗 Anthropology 🔗 Syria 🔗 Sociology 🔗 Ethnic groups 🔗 Arab world 🔗 Israel 🔗 Palestine 🔗 Islam/Shi'a Islam 🔗 Lebanon

The Druze (; Arabic: دَرْزِيٌّ, darzī or Arabic: دُرْزِيٌّ durzī, pl. دُرُوزٌ, durūz), known to adherents as al-Muwaḥḥidūn (Monotheists) or Muwaḥḥidūn (unitarians), are an Arab and Arabic-speaking esoteric ethnoreligious group from Western Asia who adhere to the Druze faith, an Abrahamic, monotheistic, syncretic, and ethnic religion whose main tenets are the unity of God and the belief in reincarnation and the eternity of the soul. Adherents of the Druze religion call themselves simply "the Monotheists" (al-Muwaḥḥidūn). Most Druze religious practices are kept secret. The Druze do not permit outsiders to convert to their religion. Marriage outside the Druze faith is rare and strongly discouraged.

The Epistles of Wisdom is the foundational and central text of the Druze faith. The Druze faith incorporates elements of Isma'ilism, Christianity, Gnosticism, Neoplatonism, Zoroastrianism, Buddhism, Hinduism, Pythagoreanism, and other philosophies and beliefs, creating a distinct and secretive theology based on an esoteric interpretation of scripture, which emphasizes the role of the mind and truthfulness. Druze believe in theophany and reincarnation. Druze believe that at the end of the cycle of rebirth, which is achieved through successive reincarnations, the soul is united with the Cosmic Mind (al-ʻaql al-kullī).

The Druze have a special reverence for Shuaib, who they believe is the same person as the biblical Jethro. The Druze believe that Adam, Noah, Abraham, Moses, Jesus, Muhammad, and Isma'il ibn Ja'far were prophets. Druze tradition also honors and reveres Salman the Persian, al-Khidr (who they identify as Elijah, reborn as John the Baptist and Saint George), Job, Luke the Evangelist, and others as "mentors" and "prophets".

Even though the faith originally developed out of Isma'ilism, the Druze are not Muslims. The Druze faith is one of the major religious groups in the Levant, with between 800,000 and a million adherents. They are found primarily in Lebanon, Syria, and Israel, with small communities in Jordan. They make up 5.5% of the population of Lebanon, 3% of Syria and 1.6% of Israel. The oldest and most densely-populated Druze communities exist in Mount Lebanon and in the south of Syria around Jabal al-Druze (literally the "Mountain of the Druze").

The Druze community played a critically important role in shaping the history of the Levant, where it continues to play a significant political role. As a religious minority in every country in which they are found, they have frequently experienced persecution by different Muslim regimes, including contemporary Islamic extremism.

🔗 Mathematics

In mathematics, a combinatorial explosion is the rapid growth of the complexity of a problem due to how the combinatorics of the problem is affected by the input, constraints, and bounds of the problem. Combinatorial explosion is sometimes used to justify the intractability of certain problems. Examples of such problems include certain mathematical functions, the analysis of some puzzles and games, and some pathological examples which can be modelled as the Ackermann function.

🔗 Volcanoes 🔗 Islands 🔗 Sicily 🔗 Seamounts

Graham Island (also Graham Bank or Graham Shoal; Italian: Isola Ferdinandea) is a submerged volcanic island in the Mediterranean Sea. It was discovered when it last appeared on 1 August 1831 by Humphrey Fleming Senhouse, the captain of the first rate Royal Navy ship of the line St Vincent and named after Sir James Graham, the First Lord of the Admiralty. It was claimed by the United Kingdom. It forms part of the underwater volcano Empedocles, 30 km (19 mi) south of Sicily, and which is one of a number of submarine volcanoes known as the Campi Flegrei del Mar di Sicilia. Seamount eruptions have raised it above sea level several times before erosion submerged it again.

When it last rose above sea level after erupting in 1831, a four-way dispute over its sovereignty began, which was still unresolved when it disappeared beneath the waves again in early 1832. During its brief life, French geologist Constant Prévost was on hand, accompanied by an artist, to witness it in July 1831; he named it Île Julia, for its July appearance, and reported in the Bulletin de la Société Géologique de France. Some observers at the time wondered if a chain of mountains would spring up, linking Sicily to Tunisia and thus upsetting the geopolitics of the region. It showed signs of volcanic activity in 2000 and 2002, forecasting a possible appearance; however, as of 2016 it remains 6 m (20 ft) under sea level.