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๐Ÿ”— 1918 Spanish Flu

๐Ÿ”— History ๐Ÿ”— Disaster management ๐Ÿ”— Medicine ๐Ÿ”— Viruses ๐Ÿ”— Death ๐Ÿ”— Globalization

The Spanish flu (also known as the 1918 flu pandemic) was an unusually deadly influenza pandemic. Lasting from January 1918 to December 1920, it infected 500ย million peopleโ€”about a quarter of the world's population at the time. The death toll is estimated to have been anywhere from 17ย million to 50ย million, and possibly as high as 100ย million, making it one of the deadliest pandemics in human history.

To maintain morale, World War I censors minimized early reports of illness and mortality in Germany, the United Kingdom, France, and the United States. Papers were free to report the epidemic's effects in neutral Spain, such as the grave illness of King Alfonso XIII, and these stories created a false impression of Spain as especially hard hit. This gave rise to the pandemic's nickname, "Spanish flu". Historical and epidemiological data are inadequate to identify with certainty the pandemic's geographic origin, with varying views as to the origin.

Most influenza outbreaks disproportionately kill the very young and the very old, with a higher survival rate for those in between, but the Spanish flu pandemic resulted in a higher than expected mortality rate for young adults. Scientists offer several possible explanations for the high mortality rate of the 1918 influenza pandemic. Some analyses have shown the virus to be particularly deadly because it triggers a cytokine storm, which ravages the stronger immune system of young adults. In contrast, a 2007 analysis of medical journals from the period of the pandemic found that the viral infection was no more aggressive than previous influenza strains. Instead, malnourishment, overcrowded medical camps and hospitals, and poor hygiene promoted bacterial superinfection. This superinfection killed most of the victims, typically after a somewhat prolonged death bed.

The Spanish flu was the first of two pandemics caused by the H1N1 influenza virus; the second was the swine flu in 2009.

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๐Ÿ”— Harvard Mark I

๐Ÿ”— Computing ๐Ÿ”— Computing/Early computers

The IBM Automatic Sequence Controlled Calculator (ASCC), called Mark I by Harvard Universityโ€™s staff, was a general purpose electromechanical computer that was used in the war effort during the last part of World War II.

One of the first programs to run on the Mark I was initiated on 29 March 1944 by John von Neumann. At that time, von Neumann was working on the Manhattan Project, and needed to determine whether implosion was a viable choice to detonate the atomic bomb that would be used a year later. The Mark I also computed and printed mathematical tables, which had been the initial goal of British inventor Charles Babbage for his "analytical engine".

The Mark I was disassembled in 1959, but portions of it are displayed in the Science Center as part of the Harvard Collection of Historical Scientific Instruments. Other sections of the original machine were transferred to IBM and the Smithsonian Institution.

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๐Ÿ”— Kriegspiel

๐Ÿ”— Chess

Kriegspiel is a chess variant invented by Henry Michael Temple in 1899 and based upon the original Kriegsspiel (German for war game) developed by Georg von Reiswitz in 1812. In this game each player can see their own pieces, but not those of their opponent. For this reason, it is necessary to have a third person (or computer) act as an umpire, with full information about the progress of the game. When it is a player's turn he or she will attempt a move, which the umpire will declare to be 'legal' or 'illegal'. If the move is illegal, the player tries again; if it is legal, that move stands. Each player is given information about checks and captures. They may also ask the umpire if there are any legal captures with a pawn. Since the position of the opponent's pieces is unknown, Kriegspiel is a game of imperfect information. The game is sometimes referred to as blind chess.

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๐Ÿ”— .yu domain expires today (30/Sept/2009)

๐Ÿ”— Internet ๐Ÿ”— Serbia ๐Ÿ”— Yugoslavia

.yu was the Internet country code top-level domain (ccTLD) that was assigned to Yugoslavia and was mainly used by the Federal Republic of Yugoslavia and its successor states from 1994 and 2010. After Serbia and Montenegro acquired separate .rs and .me domains in 2007, a transition period started, and the .yu domain finally expired on 30 March 2010. It was the most heavily used top-level domain ever to be deleted, as usage of Internet was much higher than in the beginning of 1990s, at the time of German reunification, and the dissolutions of Czechoslovakia and the Soviet Union.

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๐Ÿ”— Loving v. Virginia

๐Ÿ”— United States ๐Ÿ”— Law ๐Ÿ”— Women's History ๐Ÿ”— LGBT studies ๐Ÿ”— Virginia ๐Ÿ”— African diaspora ๐Ÿ”— Civil Rights Movement ๐Ÿ”— U.S. Supreme Court cases

Loving v. Virginia, 388 U.S. 1 (1967), was a landmark civil rights decision of the U.S. Supreme Court in which the Court ruled that laws banning interracial marriage violate the Equal Protection and Due Process Clauses of the Fourteenth Amendment to the U.S. Constitution. Beginning in 2013, it was cited as precedent in U.S. federal court decisions holding restrictions on same-sex marriage in the United States unconstitutional, including in the 2015 Supreme Court decision Obergefell v. Hodges.

The case involved Mildred Loving, a woman of color, and her white husband Richard Loving, who in 1958 were sentenced to a year in prison for marrying each other. Their marriage violated Virginia's Racial Integrity Act of 1924, which criminalized marriage between people classified as "white" and people classified as "colored". The Lovings appealed their conviction to the Supreme Court of Virginia, which upheld it. They then appealed to the U.S. Supreme Court, which agreed to hear their case.

In June 1967, the Supreme Court issued a unanimous decision in the Lovings' favor and overturned their convictions. Its decision struck down Virginia's anti-miscegenation law and ended all race-based legal restrictions on marriage in the United States. Virginia had argued that its law was not a violation of the Equal Protection Clause because the punishment was the same regardless of the offender's race, and thus it "equally burdened" both whites and non-whites. The Court found that the law nonetheless violated the Equal Protection Clause because it was based solely on "distinctions drawn according to race" and outlawed conductโ€”namely, getting marriedโ€”that was otherwise generally accepted and which citizens were free to do.

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๐Ÿ”— Bioluminescence

๐Ÿ”— Chemistry ๐Ÿ”— Animals ๐Ÿ”— Molecular Biology/Molecular and Cell Biology

Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.

In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin.

In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and sometimes also the energy-carrying molecule adenosine triphosphate (ATP). In evolution, luciferins vary little: one in particular, coelenterazine, is found in 11 different animal phyla, though in some of these, the animals obtain it through their diet. Conversely, luciferases vary widely between different species, which is evidence that bioluminescence has arisen over 40 times in evolutionary history.

Both Aristotle and Pliny the Elder mentioned that damp wood sometimes gives off a glow. Many centuries later Robert Boyle showed that oxygen was involved in the process, in both wood and glowworms. It was not until the late nineteenth century that bioluminescence was properly investigated. The phenomenon is widely distributed among animal groups, especially in marine environments. On land it occurs in fungi, bacteria and some groups of invertebrates, including insects.

The uses of bioluminescence by animals include counterillumination camouflage, mimicry of other animals, for example to lure prey, and signaling to other individuals of the same species, such as to attract mates. In the laboratory, luciferase-based systems are used in genetic engineering and biomedical research. Researchers are also investigating the possibility of using bioluminescent systems for street and decorative lighting, and a bioluminescent plant has been created.

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๐Ÿ”— Relativistic kill vehicle

๐Ÿ”— Physics ๐Ÿ”— Firearms

A projectile is any object thrown into space (empty or not) by the exertion of a force. Although any object in motion through space (for example a thrown baseball) may be called a projectile, the term more commonly refers to a ranged weapon. Mathematical equations of motion are used to analyze projectile trajectory. An object projected at an angle to the horizontal has both the vertical and horizontal components of velocity. The vertical component of the velocity on the y-axis given as Vy=USin(teta) while the horizontal component of the velocity Vx=UCos(teta). There are various terms used in projectiles at specific angle teta 1. Time to reach maximum height. It is symbolized as (t), which is the time taken for the projectile to reach the maximum height from the plane of projection. Mathematically, it is given as t=USin(teta)/g Where g=acceleration due to gravity(app 9.81m/sยฒ) U= initial velocity (m/s) teta= angle made by the projectile with the horizontal axis.

2. Time of flight (T): this is the total time taken for the projectile to fall back to the same plane from which it was projected. Mathematically it is given as T=2USin(teta)/g

3. Maximum Height (H): this is the maximum height attained by the projectile OR the maximum displacement on the vertical axis(y-axis) covered by the projectile. It is given as H= UยฒSinยฒ(teta)/2g

4. Range(R): The Range of a projectile is the horizontal distance covered (on the x-axis) by the projectile. Mathematically, R= UยฒSin2(teta)/g. The Range is maximum when angle teta= 45ยฐ I.e Sin2(teta)=1.

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๐Ÿ”— Terror management theory

๐Ÿ”— Psychology

Terror management theory (TMT) is both a social and evolutionary psychology theory originally proposed by Jeff Greenberg, Sheldon Solomon, and Tom Pyszczynski and codified in their book The Worm at the Core: On the Role of Death in Life (2015). It proposes that a basic psychological conflict results from having a self-preservation instinct while realizing that death is inevitable and to some extent unpredictable. This conflict produces terror, and the terror is then managed by embracing cultural beliefs, or symbolic systems that act to counter biological reality with more durable forms of meaning and value.

The most obvious examples of cultural values that assuage death anxiety are those that purport to offer literal immortality (e.g. belief in afterlife, religion). However, TMT also argues that other cultural valuesย โ€“ including those that are seemingly unrelated to deathย โ€“ offer symbolic immortality. For example, values of national identity, posterity, cultural perspectives on sex, and human superiority over animals have been linked to death concerns. In many cases these values are thought to offer symbolic immortality either a) by providing the sense that one is part of something greater that will ultimately outlive the individual (e.g. country, lineage, species), or b) by making one's symbolic identity superior to biological nature (i.e. you are a personality, which makes you more than a glob of cells).

Because cultural values determine that which is meaningful, they are also the foundation for self-esteem. TMT describes self-esteem as being the personal, subjective measure of how well an individual is living up to their cultural values.

TMT is derived from anthropologist Ernest Becker's 1973ย Pulitzer Prize-winning work of nonfiction The Denial of Death, in which Becker argues most human action is taken to ignore or avoid the inevitability of death. The terror of absolute annihilation creates such a profoundย โ€“ albeit subconsciousย โ€“ anxiety in people that they spend their lives attempting to make sense of it. On large scales, societies build symbols: laws, religious meaning systems, cultures, and belief systems to explain the significance of life, define what makes certain characteristics, skills, and talents extraordinary, reward others whom they find exemplify certain attributes, and punish or kill others who do not adhere to their cultural worldview. On an individual level, self-esteem provides a buffer against death-related anxiety.

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๐Ÿ”— Why less competent may rate their own ability higher than more competent

๐Ÿ”— Business ๐Ÿ”— Psychology ๐Ÿ”— Alternative Views ๐Ÿ”— Education

In the field of psychology, the Dunningโ€“Kruger effect is a cognitive bias in which people assess their cognitive ability as greater than it is. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their lack of ability. Without the self-awareness of metacognition, people cannot objectively evaluate their competence or incompetence.

As described by social psychologists David Dunning and Justin Kruger, the cognitive bias of illusory superiority results from an internal illusion in people of low ability and from an external misperception in people of high ability; that is, "the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others."

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