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🔗 Marsh Chapel Experiment

🔗 Psychoactive and Recreational Drugs

The Marsh Chapel Experiment, also called the "Good Friday Experiment", was a 1962 experiment conducted on Good Friday at Boston University's Marsh Chapel. Walter N. Pahnke, a graduate student in theology at Harvard Divinity School, designed the experiment under the supervision of Timothy Leary, Richard Alpert, and the Harvard Psilocybin Project. Pahnke's experiment investigated whether psilocybin (the active principle in psilocybin mushrooms) would act as a reliable entheogen in religiously predisposed subjects.

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🔗 Anton (computer)

🔗 Computing

Anton is a massively parallel supercomputer designed and built by D. E. Shaw Research in New York, first running in 2008. It is a special-purpose system for molecular dynamics (MD) simulations of proteins and other biological macromolecules. An Anton machine consists of a substantial number of application-specific integrated circuits (ASICs), interconnected by a specialized high-speed, three-dimensional torus network.

Unlike earlier special-purpose systems for MD simulations, such as MDGRAPE-3 developed by RIKEN in Japan, Anton runs its computations entirely on specialized ASICs, instead of dividing the computation between specialized ASICs and general-purpose host processors.

Each Anton ASIC contains two computational subsystems. Most of the calculation of electrostatic and van der Waals forces is performed by the high-throughput interaction subsystem (HTIS). This subsystem contains 32 deeply pipelined modules running at 800 MHz arranged much like a systolic array. The remaining calculations, including the bond forces and the fast Fourier transforms (used for long-range electrostatics), are performed by the flexible subsystem. This subsystem contains four general-purpose Tensilica cores (each with cache and scratchpad memory) and eight specialized but programmable SIMD cores called geometry cores. The flexible subsystem runs at 400 MHz.

Anton's network is a 3D torus and thus each chip has 6 inter-node links with a total in+out bandwidth of 607.2 Gbit/s. An inter-node link is composed of two equal one-way links (one traveling in each direction), with each one-way link having 50.6 Gbit/s of bandwidth. Each one-way link is composed of 11 lanes, where a lane is a differential pair of wires signaling at 4.6 Gbit/s. The per-hop latency in Anton's network is 50 ns. Each ASIC is also attached to its own DRAM bank, enabling large simulations.

The performance of a 512-node Anton machine is over 17,000 nanoseconds of simulated time per day for a protein-water system consisting of 23,558 atoms. In comparison, MD codes running on general-purpose parallel computers with hundreds or thousands of processor cores achieve simulation rates of up to a few hundred nanoseconds per day on the same chemical system. The first 512-node Anton machine became operational in October 2008. The multiple petaFLOP, distributed-computing project Folding@home has achieved similar aggregate ensemble simulation timescales, comparable to the total time of a single continuous simulation on Anton, specifically achieving the 1.5-millisecond range in January 2010.

The Anton supercomputer is named after Anton van Leeuwenhoek, who is often referred to as "the father of microscopy" because he built high-precision optical instruments and used them to visualize a wide variety of organisms and cell types for the first time.

The ANTON 2 machine with four 512 nodes and substantially increased speed and problem size has been described.

The National Institutes of Health have supported an ANTON for the biomedical research community at the Pittsburgh Supercomputing Center, Carnegie-Mellon University, and recently approved support of an ANTON 2 there.

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🔗 August Engelhardt

🔗 Biography 🔗 Biography/science and academia 🔗 Food and drink 🔗 Alternative medicine 🔗 Papua New Guinea

August Engelhardt (27 November 1875 – 6 May 1919) was a German author and founder of a sect of sun worshipers.

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🔗 OK Soda

🔗 Food and drink 🔗 Brands 🔗 Food and drink/Beverages

OK Soda was a soft drink created by The Coca-Cola Company in 1993 that courted the American Generation X demographic with unusual advertising tactics, including neo-noir design, chain letters and deliberately negative publicity. After the soda did not sell well in select test markets, it was officially declared out of production in 1995 before reaching nationwide distribution. The drink's slogan was "Things are going to be OK."

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🔗 Musth

🔗 Mammals

Musth or must (an Urdu word, from Persian, lit. drunk) is a periodic condition in bull (male) elephants characterized by highly aggressive behavior and accompanied by a large rise in reproductive hormones.

Testosterone levels in an elephant in musth can be on average 60 times greater than in the same elephant at other times (in specific individuals these testosterone levels can even reach as much as 140 times the normal). However, whether this hormonal surge is the sole cause of musth, or merely a contributing factor, is unknown.

Scientific investigation of musth is problematic because even the most placid elephants become highly violent toward humans and other elephants during musth.

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  • "Musth" | 2020-04-06 | 77 Upvotes 15 Comments

🔗 Problem of Time

🔗 Physics 🔗 Philosophy 🔗 Philosophy/Philosophy of science 🔗 Philosophy/Contemporary philosophy

In theoretical physics, the problem of time is a conceptual conflict between general relativity and quantum mechanics in that quantum mechanics regards the flow of time as universal and absolute, whereas general relativity regards the flow of time as malleable and relative. This problem raises the question of what time really is in a physical sense and whether it is truly a real, distinct phenomenon. It also involves the related question of why time seems to flow in a single direction, despite the fact that no known physical laws seem to require a single direction.

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🔗 Tired Mountain Syndrome

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Geology 🔗 Explosives

Tired mountain syndrome is a condition in which underground nuclear testing fractures and weakens rock, increasing permeability and the risk of release of radionuclides and radioactive contamination of the environment. Locations said to have undergone the syndrome include the French Polynesian island of Moruroa, Rainier Mesa in the United States, the Dnepr 1 nuclear test site on the Kola Peninsula in Russia, possibly Mount Lazarev in the Novaya Zemlya Test Site in Russia, and Mount Mantap in North Korea.

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🔗 Zerah Colburn (Mental Calculator)

🔗 United States 🔗 Biography 🔗 Mathematics 🔗 United States/Vermont

Zerah Colburn (September 1, 1804 – March 2, 1840) was a child prodigy of the 19th century who gained fame as a mental calculator.

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🔗 James Dewar

🔗 Biography 🔗 Physics 🔗 Biography/science and academia 🔗 Physics/Biographies

Sir James Dewar (20 September 1842 – 27 March 1923) was a Scottish chemist and physicist. He is best known for his invention of the vacuum flask, which he used in conjunction with research into the liquefaction of gases. He also studied atomic and molecular spectroscopy, working in these fields for more than 25 years.

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🔗 The Opium of the Intellectuals

🔗 Books

The Opium of the Intellectuals (French: L'Opium des intellectuels) is a book written by Raymond Aron and published in 1955. It was first published in an English translation in 1957.

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