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🔗 Physiology 🔗 Evolutionary biology

In evolutionary biology and evolutionary psychology, the Trivers–Willard hypothesis, formally proposed by Robert Trivers and Dan Willard in 1973, suggests that female mammals are able to adjust offspring sex ratio in response to their maternal condition. For example, it may predict greater parental investment in males by parents in "good conditions" and greater investment in females by parents in "poor conditions" (relative to parents in good condition). The reasoning for this prediction is as follows: Assume that parents have information on the sex of their offspring and can influence their survival differentially. While pressures exist to maintain sex ratios at 50%, evolution will favor local deviations from this if one sex has a likely greater reproductive payoff than is usual.

Trivers and Willard also identified a circumstance in which reproducing individuals might experience deviations from expected offspring reproductive value—namely, varying maternal condition. In polygynous species males may mate with multiple females and low-condition males will achieve fewer or no matings. Parents in relatively good condition would then be under selection for mutations causing production and investment in sons (rather than daughters), because of the increased chance of mating experienced by these good-condition sons. Mating with multiple females conveys a large reproductive benefit, whereas daughters could translate their condition into only smaller benefits. An opposite prediction holds for poor-condition parents—selection will favor production and investment in daughters, so long as daughters are likely to be mated, while sons in poor condition are likely to be out-competed by other males and end up with zero mates (i.e., those sons will be a reproductive dead end).

The hypothesis was used to explain why, for example, Red Deer mothers would produce more sons when they are in good condition, and more daughters when in poor condition. In polyandrous species where some females mate with multiple males (and others get no matings) and males mate with one/few females (i.e., "sex-role reversed" species), these predictions from the Trivers–Willard hypothesis are reversed: parents in good condition will invest in daughters in order to have a daughter that can out-compete other females to attract multiple males, whereas parents in poor condition will avoid investing in daughters who are likely to get out-competed and will instead invest in sons in order to gain at least some grandchildren.

"Condition" can be assessed in multiple ways, including body size, parasite loads, or dominance, which has also been shown in macaques (Macaca sylvanus) to affect the sex of offspring, with dominant females giving birth to more sons and non-dominant females giving birth to more daughters. Consequently, high-ranking females give birth to a higher proportion of males than those who are low-ranking.

In their original paper, Trivers and Willard were not yet aware of the biochemical mechanism for the occurrence of biased sex ratios. Eventually, however, Melissa Larson et al. (2001) proposed that a high level of circulating glucose in the mother's bloodstream may favor the survival of male blastocysts. This conclusion is based on the observed male-skewed survival rates (to expanded blastocyst stages) when bovine blastocysts were exposed to heightened levels of glucose. As blood glucose levels are highly correlated with access to high-quality food, blood glucose level may serve as a proxy for "maternal condition". Thus, heightened glucose functions as one possible biochemical mechanism for observed Trivers–Willard effects.

Wild and West published a paper describing a mathematical model built on the Trivers–Willard hypothesis that allows precise predictions of alterations in sex-ratio under different circumstances.

🔗 Economics 🔗 New York City

The National Debt Clock is a billboard-sized running total display which constantly updates to show the current United States gross national debt and each American family's share of the debt. It is currently installed on the western side of One Bryant Park, west of Sixth Avenue between 42nd and 43rd Streets in Manhattan, New York City. It was the first debt clock installed anywhere.

The idea for the clock came from New York real estate developer Seymour Durst, who wanted to highlight the rising national debt. In 1989, he sponsored the installation of the first clock, which was originally placed on Sixth Avenue between 42nd and 43rd Streets, one block away from Times Square. In 2004, the original clock was dismantled and replaced by a newer clock near 44th Street and Sixth Avenue. In 2008, as the U.S. national debt exceeded $10 trillion for the first time, it was reported that the value of the debt may have exceeded the number of digits in the clock. The lit dollar-sign in the clock's leftmost digit position was later changed to the "1" digit to represent the ten-trillionth place. In 2017, the clock was moved again to One Bryant Park, near its original location.

🔗 Transport 🔗 Trains

The Cosmopolitan Railway was a proposed global railroad network advocated by William Gilpin, formerly the first territorial governor of Colorado (1861–62), in his 1890 treatise Cosmopolitan Railway: Compacting and Fusing Together All the World's Continents. Gilpin named his capital city of Denver as the "railroad centre of the West".

🔗 Physics 🔗 Astronomy 🔗 Chemistry 🔗 Water 🔗 Astronomy/Solar System

Superionic water, also called superionic ice or ice XVIII, is a phase of water that exists at extremely high temperatures and pressures. In superionic water, water molecules break apart and the oxygen ions crystallize into an evenly spaced lattice while the hydrogen ions float around freely within the oxygen lattice. The freely mobile hydrogen ions make superionic water almost as conductive as typical metals, making it a superionic conductor. It is one of the 19 known crystalline phases of ice. Superionic water is distinct from ionic water, which is a hypothetical liquid state characterized by a disordered soup of hydrogen and oxygen ions.

While theorized for decades, it was not until the 1990s that the first experimental evidence emerged for superionic water. Initial evidence came from optical measurements of laser-heated water in a diamond anvil cell, and from optical measurements of water shocked by extremely powerful lasers. The first definitive evidence for the crystal structure of the oxygen lattice in superionic water came from x-ray measurements on laser-shocked water which were reported in 2019.

If it were present on the surface of the Earth, superionic ice would rapidly decompress. In May 2019, scientists at the Lawrence Livermore National Laboratory (LLNL) were able to synthesize superionic ice, confirming it to be almost four times as dense as normal ice and black in color.

Superionic water is theorized to be present in the mantles of giant planets such as Uranus and Neptune.

🔗 History 🔗 Military history 🔗 British Empire 🔗 Military history/World War I 🔗 Politics of the United Kingdom 🔗 Arab world 🔗 Jewish history 🔗 Israel 🔗 Palestine 🔗 Former countries 🔗 Military history/Middle Eastern military history 🔗 Former countries/Ottoman Empire 🔗 British Library

The Balfour Declaration was a public statement issued by the British government in 1917 during the First World War announcing its support for the establishment of a "national home for the Jewish people" in Palestine, then an Ottoman region with a small minority Jewish population. The declaration was contained in a letter dated 2 November 1917 from the United Kingdom's Foreign Secretary Arthur Balfour to Lord Rothschild, a leader of the British Jewish community, for transmission to the Zionist Federation of Great Britain and Ireland. The text of the declaration was published in the press on 9 November 1917.

Immediately following their declaration of war on the Ottoman Empire in November 1914, the British War Cabinet began to consider the future of Palestine; within two months a memorandum was circulated to the Cabinet by a Zionist Cabinet member, Herbert Samuel, proposing the support of Zionist ambitions in order to enlist the support of Jews in the wider war. A committee was established in April 1915 by British Prime Minister H. H. Asquith to determine their policy towards the Ottoman Empire including Palestine. Asquith, who had favoured post-war reform of the Ottoman Empire, resigned in December 1916; his replacement David Lloyd George favoured partition of the Empire. The first negotiations between the British and the Zionists took place at a conference on 7 February 1917 that included Sir Mark Sykes and the Zionist leadership. Subsequent discussions led to Balfour's request, on 19 June, that Rothschild and Chaim Weizmann submit a draft of a public declaration. Further drafts were discussed by the British Cabinet during September and October, with input from Zionist and anti-Zionist Jews but with no representation from the local population in Palestine.

By late 1917, in the lead-up to the Balfour Declaration, the wider war had reached a stalemate, with two of Britain's allies not fully engaged: the United States had yet to suffer a casualty, and the Russians were in the midst of a revolution with Bolsheviks taking over the government. A stalemate in southern Palestine was broken by the Battle of Beersheba on 31 October 1917. The release of the final declaration was authorised on 31 October; the preceding Cabinet discussion had referenced perceived propaganda benefits amongst the worldwide Jewish community for the Allied war effort.

The opening words of the declaration represented the first public expression of support for Zionism by a major political power. The term "national home" had no precedent in international law, and was intentionally vague as to whether a Jewish state was contemplated. The intended boundaries of Palestine were not specified, and the British government later confirmed that the words "in Palestine" meant that the Jewish national home was not intended to cover all of Palestine. The second half of the declaration was added to satisfy opponents of the policy, who had claimed that it would otherwise prejudice the position of the local population of Palestine and encourage antisemitism worldwide by "stamping the Jews as strangers in their native lands". The declaration called for safeguarding the civil and religious rights for the Palestinian Arabs, who composed the vast majority of the local population, and also the rights and political status of the Jewish communities in other countries outside of Palestine. The British government acknowledged in 1939 that the local population's wishes and interests should have been taken into account, and recognised in 2017 that the declaration should have called for the protection of the Palestinian Arabs' political rights.

The declaration had many long-lasting consequences. It greatly increased popular support for Zionism within Jewish communities worldwide, and became a core component of the British Mandate for Palestine, the founding document of Mandatory Palestine. It indirectly led to the emergence of Israel and is considered a principal cause of the ongoing Israeli–Palestinian conflict, often described as the world's most intractable conflict. Controversy remains over a number of areas, such as whether the declaration contradicted earlier promises the British made to the Sharif of Mecca in the McMahon–Hussein correspondence.

🔗 United States 🔗 Biography 🔗 California 🔗 Aviation 🔗 Spaceflight 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Biography/science and academia 🔗 Military history/Military biography 🔗 Biography/military biography 🔗 LGBT studies 🔗 Aviation/aerospace biography 🔗 Chemistry 🔗 Military history/World War II 🔗 Military history/Cold War 🔗 Libertarianism 🔗 California/Southern California 🔗 California/Los Angeles area 🔗 Thelema 🔗 Occult

John Whiteside Parsons (born Marvel Whiteside Parsons; October 2, 1914 – June 17, 1952) was an American rocket engineer, chemist, and Thelemite occultist. Associated with the California Institute of Technology (Caltech), Parsons was one of the principal founders of both the Jet Propulsion Laboratory (JPL) and the Aerojet Engineering Corporation. He invented the first rocket engine to use a castable, composite rocket propellant, and pioneered the advancement of both liquid-fuel and solid-fuel rockets.

Born in Los Angeles, Parsons was raised by a wealthy family on Orange Grove Boulevard in Pasadena. Inspired by science fiction literature, he developed an interest in rocketry in his childhood and in 1928 began amateur rocket experiments with school friend Edward S. Forman. He dropped out of Pasadena Junior College and Stanford University due to financial difficulties during the Great Depression, and in 1934 he united with Forman and graduate Frank Malina to form the Caltech-affiliated Guggenheim Aeronautical Laboratory (GALCIT) Rocket Research Group, supported by GALCIT chairman Theodore von Kármán. In 1939 the GALCIT Group gained funding from the National Academy of Sciences (NAS) to work on Jet-Assisted Take Off (JATO) for the U.S. military. After the U.S. entered World War II, they founded Aerojet in 1942 to develop and sell JATO technology; the GALCIT Group became JPL in 1943.

Following some brief involvement with Marxism in 1939, Parsons converted to Thelema, the new religious movement founded by the English occultist Aleister Crowley. Together with his first wife, Helen Northrup, Parsons joined the Agape Lodge, the Californian branch of the Thelemite Ordo Templi Orientis (O.T.O.) in 1941. At Crowley's bidding, Parsons replaced Wilfred Talbot Smith as its leader in 1942 and ran the Lodge from his mansion on Orange Grove Boulevard. Parsons was expelled from JPL and Aerojet in 1944 owing to the Lodge's infamous reputation and to his hazardous workplace conduct.

In 1945, Parsons separated from Helen, after having an affair with her sister Sara; when Sara left him for L. Ron Hubbard, Parsons conducted the Babalon Working, a series of rituals intended to invoke the Thelemic goddess Babalon on Earth. He and Hubbard continued the working with Marjorie Cameron, whom Parsons married in 1946. After Hubbard and Sara defrauded him of his life savings, Parsons resigned from the O.T.O., then held various jobs while acting as a consultant for Israel's rocket program. Amid McCarthyism, Parsons was accused of espionage and left unable to work in rocketry. In 1952 Parsons died at the age of 37 in a home laboratory explosion that attracted national media attention; the police ruled it an accident, but many associates suspected suicide or murder.

Parsons's libertarian and occult writings were published posthumously. Historians of Western esoteric tradition cite him as one of the more prominent figures in propagating Thelema across North America. Although academic interest in his scientific career was negligible, historians have come to recognize Parsons's contributions to rocket engineering. For these innovations, his advocacy of space exploration and human spaceflight, and his role in founding JPL and Aerojet, Parsons is regarded as among the most important figures in the history of the U.S. space program. He has been the subject of several biographies and fictionalized portrayals.

🔗 Geography

The First Law of Geography, according to Waldo Tobler, is "everything is related to everything else, but near things are more related than distant things." This first law is the foundation of the fundamental concepts of spatial dependence and spatial autocorrelation and is utilized specifically for the inverse distance weighting method for spatial interpolation and to support the regionalized variable theory for kriging. It is a modern formulation of David Hume's principle of contiguity.

Tobler first presented his seminal idea during a meeting of the International Geographical Union's Commission on Qualitative Methods held in 1969 and later published by him in 1970. Though simple in its presentation, this idea is profound. Without it, "the full range of conditions anywhere on the Earth's surface could in principle be found packed within any small area. There would be no regions of approximately homogeneous conditions to be described by giving attributes to area objects. Topographic surfaces would vary chaotically, with slopes that were everywhere infinite, and the contours of such surfaces would be infinitely dense and contorted. Spatial analysis, and indeed life itself, would be impossible."

Less well known is his second law, which complements the first: "The phenomenon external to an area of interest affects what goes on inside".

🔗 Robotics

Q-learning is a model-free reinforcement learning algorithm to learn a policy telling an agent what action to take under what circumstances. It does not require a model (hence the connotation "model-free") of the environment, and it can handle problems with stochastic transitions and rewards, without requiring adaptations.

For any finite Markov decision process (FMDP), Q-learning finds an optimal policy in the sense maximizing the expected value of the total reward over any and all successive steps, starting from the current state. Q-learning can identify an optimal action-selection policy for any given FMDP, given infinite exploration time and a partly-random policy. "Q" names the function that returns the reward used to provide the reinforcement and can be said to stand for the "quality" of an action taken in a given state.

🔗 Internet 🔗 Computing 🔗 Literature

Foetry.com, sometimes referred to as just Foetry, was a website that attempted to identify fraudulent and unethical practices in poetry contests. It was active from April 1, 2004 until May 18, 2007.

Noblesse oblige (; French: [nɔblɛs ɔbliʒ]) is a French expression used in English meaning that nobility extends beyond mere entitlements and requires the person who holds such a status to fulfill social responsibilities. For example, a primary obligation of a nobleman could include generosity towards those around him.

The Oxford English Dictionary states that the term suggests "noble ancestry constrains to honourable behaviour; privilege entails responsibility."

The Dictionnaire de l'Académie française defines it thus:

1. Whoever claims to be noble must conduct himself nobly.
2. (Figuratively) One must act in a fashion that conforms to one's position and privileges with which one has been born, bestowed and/or has earned.