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πŸ”— Behavioral Immune System

πŸ”— Psychology

The behavioral immune system is a phrase coined by the psychological scientist Mark Schaller to refer to a suite of psychological mechanisms that allow individual organisms to detect the potential presence of disease-causing parasites in their immediate environment, and to engage in behaviors that prevent contact with those objects and individuals.

These mechanisms include sensory processes through which cues connoting the presence of parasitic infections are perceived (e.g., the smell of a foul odor, the sight of pox or pustules), as well as stimulus–response systems through which these sensory cues trigger a cascade of aversive affective, cognitive, and behavioral reactions (e.g., arousal of disgust, automatic activation of cognitions that connote the threat of disease, behavioral avoidance).

The existence of a behavioral immune system has been documented across many animal species, including humans. It is theorized that the mechanisms that comprise the behavioral immune system evolved as a crude first line of defense against disease-causing pathogens.

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πŸ”— Joy (Programming Language)

πŸ”— Software πŸ”— Software/Computing

The Joy programming language in computer science is a purely functional programming language that was produced by Manfred von Thun of La Trobe University in Melbourne, Australia. Joy is based on composition of functions rather than lambda calculus. It has turned out to have many similarities to Forth, due not to design but to a sort of parallel evolution and convergence. It was also inspired by the function-level programming style of John Backus's FP.

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πŸ”— Guthrie's One Trial Theory

πŸ”— Biography πŸ”— Psychology πŸ”— Biography/science and academia

Edwin Ray Guthrie (; January 9, 1886 in Lincoln, Nebraska – April 23, 1959 in Seattle, Washington) was a behavioral psychologist. He first worked as a mathematics teacher, and philosopher, but switched to psychology when he was 33. He spent most of his career at the University of Washington, where he became full professor and then emeritus professor in psychology.

Guthrie is best known for his theory that all learning was based on a stimulus–response association. This was variously described as one trial theory, non-reinforcement, and contiguity learning. The theory was:

"A combination of stimuli which has accompanied a movement will on its recurrence tend to be followed by that movement".

One word that his coworkers and students used to describe Guthrie and his theories was "simple", and perhaps he did prefer to use simple terms to illustrate complex ideas. However, "It is undoubtedly true that many reviews of Guthrie in the literature have mistaken incompleteness for simplicity".

His simple nature carried into his teachings where he took great pride in working with and teaching students.

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πŸ”— Alan L. Hart

πŸ”— Biography πŸ”— Oregon πŸ”— LGBT studies

Alan L. Hart (born Alberta Lucille Hart, October 4, 1890 – July 1, 1962) was an American physician, radiologist, tuberculosis researcher, writer and novelist. He was in 1917–18 one of the first trans men to undergo hysterectomy in the United States, and lived the rest of his life as a man. He pioneered the use of x-ray photography in tuberculosis detection, and helped implement TB screening programs that saved thousands of lives.

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πŸ”— OFFSystem

πŸ”— Computing

The Owner-Free File System (OFF System, or OFF for short) is a peer-to-peer distributed file system in which all shared files are represented by randomized multi-used data blocks. Instead of anonymizing the network, the data blocks are anonymized and therefore, only data garbage is ever exchanged and stored and no forwarding via intermediate nodes is required. OFF claims to have been created with the expressed intention "to cut off some gangrene-infested bits of the copyright industry."

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πŸ”— Operation Popeye

πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Military history/Asian military history πŸ”— Military history/Southeast Asian military history πŸ”— Vietnam

Operation Popeye (Project Controlled Weather Popeye / Motorpool / Intermediary-Compatriot) was a highly classified weather modification program in Southeast Asia during 1967–1972. The cloud seeding operation during the Vietnam War ran from March 20, 1967 until July 5, 1972 in an attempt to extend the monsoon season, specifically over areas of the Ho Chi Minh Trail. The operation was used to induce rain and extend the East Asian Monsoon season in support of U.S. government efforts related to the War in Southeast Asia.

The former U.S. Secretary of Defense, Robert S. McNamara, was aware that there might be objections raised by the international scientific community but said in a memo to the president that such objections had not in the past been a basis for prevention of military activities considered to be in the interests of U.S. national security.

The chemical weather modification program was conducted from Thailand over Cambodia, Laos, and Vietnam and allegedly sponsored by Secretary of State Henry Kissinger and CIA without the authorization of then Secretary of Defense Melvin Laird who had categorically denied to Congress that a program for modification of the weather for use as a tactical weapon even existed.

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πŸ”— 0.999...= 1

πŸ”— Mathematics

In mathematics, 0.999... (also written as 0.9, among other ways) denotes the repeating decimal consisting of infinitely many 9s after the decimal point (and one 0 before it). This repeating decimal represents the smallest number no less than every decimal number in the sequence (0.9, 0.99, 0.999, ...). This number is equal to 1. In other words, "0.999..." and "1" represent the same number. There are many ways of showing this equality, from intuitive arguments to mathematically rigorous proofs. The technique used depends on the target audience, background assumptions, historical context, and preferred development of the real numbers, the system within which 0.999... is commonly defined. (In other systems, 0.999... can have the same meaning, a different definition, or be undefined.)

More generally, every nonzero terminating decimal has two equal representations (for example, 8.32 and 8.31999...), which is a property of all base representations. The utilitarian preference for the terminating decimal representation contributes to the misconception that it is the only representation. For this and other reasonsβ€”such as rigorous proofs relying on non-elementary techniques, properties, or disciplinesβ€”some people can find the equality sufficiently counterintuitive that they question or reject it. This has been the subject of several studies in mathematics education.

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πŸ”— Foucault pendulum

πŸ”— Physics

The Foucault pendulum or Foucault's pendulum is a simple device named after French physicist LΓ©on Foucault and conceived as an experiment to demonstrate the Earth's rotation. The pendulum was introduced in 1851 and was the first experiment to give simple, direct evidence of the earth's rotation. Foucault pendulums today are popular displays in science museums and universities.

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πŸ”— Wi-Fi over Coax

πŸ”— Computing

Wi-Fi over Coax is a technology for extending and distributing Wi-Fi signals via coaxial cables. As an in-building wireless solution, Wi-Fi over Coax can make use of existing or new cabling with native impedance of 50 ohms shared by a Wi-Fi access point, cabling run, and antenna. Coaxial cables with characteristic impedance of 75 ohms, such as RG-6 cables used for in-building television distribution, can also be used by incorporating impedance converters. As part of a distributed antenna system, Wi-Fi over Coax can connect multiple floors of a home or office via power dividers and zoned antennas either passively or via amplifiers, potentially eliminating the need for multiple access points.

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πŸ”— Biology and political orientation

πŸ”— Biology πŸ”— Politics πŸ”— Psychology πŸ”— Neuroscience πŸ”— Genetics πŸ”— Physiology πŸ”— Physiology/neuro πŸ”— Evolutionary biology πŸ”— Conservatism

A number of studies have found that biology can be linked with political orientation. This means that biology is a possible factor in political orientation but may also mean that the ideology a person identifies with changes a person's ability to perform certain tasks. Many of the studies linking biology to politics remain controversial and unreplicated, although the overall body of evidence is growing.

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