Have a deep view into what people are curious about.

🔗 Writing systems

Y, or y, is the 25th and penultimate letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. According to some authorities, it is the sixth (or seventh if including W) vowel letter of the English alphabet. In the English writing system, it mostly represents a vowel and seldom a consonant, and in other orthographies it may represent a vowel or a consonant. Its name in English is wye (pronounced ), plural wyes.

🔗 Finance & Investment 🔗 New York City 🔗 Fraternities and Sororities

Kappa Beta Phi (ΚΒΦ) is a secret society with at least one surviving chapter, based on Wall Street in New York City, that is made up of high-ranking financial executives. The purpose of the organization today is largely social and honorific. The current honor society meets once a year at a black-tie dinner to induct new members.

🔗 Medicine 🔗 COVID-19 🔗 Medicine/Pulmonology 🔗 Medicine/Cardiology

Extracorporeal membrane oxygenation (ECMO), also known as extracorporeal life support (ECLS), is an extracorporeal technique of providing prolonged cardiac and respiratory support to persons whose heart and lungs are unable to provide an adequate amount of gas exchange or perfusion to sustain life. The technology for ECMO is largely derived from cardiopulmonary bypass, which provides shorter-term support with arrested native circulation. The device used is a membrane oxygenator, also known as an artificial lung.

ECMO works by temporarily drawing blood from the body to allow artificial oxygenation of the red blood cells and removal of carbon dioxide. Generally, it is used either post-cardiopulmonary bypass or in late-stage treatment of a person with profound heart and/or lung failure, although it is now seeing use as a treatment for cardiac arrest in certain centers, allowing treatment of the underlying cause of arrest while circulation and oxygenation are supported. ECMO is also used to support patients with the acute viral pneumonia associated with COVID-19 in cases where artificial ventilation alone is not sufficient to sustain blood oxygenation levels.

🔗 Military history 🔗 Politics 🔗 Politics of the United Kingdom 🔗 Military history/European military history 🔗 Military history/British military history

The letters of last resort are four identically worded handwritten letters from the Prime Minister of the United Kingdom to the commanding officers of the four British ballistic missile submarines. They contain orders on what action to take in the event that an enemy nuclear strike has destroyed the British government and has killed or otherwise incapacitated both the prime minister and the "second person" (normally a high-ranking member of the Cabinet) whom the prime minister has designated to make a decision on how to act in the event of the prime minister's death. In the event that the orders are carried out, the action taken could be the last official act of Government of the United Kingdom.

The letters are stored inside two nested safes in the control room of each submarine. The letters are destroyed unopened after a prime minister leaves office, so their content remains known only to the prime minister who issued them.

Below is a mostly comprehensive gallery of all images — illustrations, diagrams and animations — that I have created for Wikipedia over the years, some of which have been selected as featured pictures, or even picture of the day. As you'll probably notice, they're mostly related to physics and mathematics, which are my main areas of interest.

If you have any comments, requests, suggestions or corrections, feel free to drop me a message on my talk page. But please, before making a suggestion, first take a look and see what sort of stuff I can do. Due to time, knowledge and complexity constraints, I cannot guarantee I'll be able to make a good illustration of any topic.

You can also follow me on tumblr for WIPs, current and failed projects and other creations.

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🔗 Astronomy 🔗 History of Science 🔗 Astronomy/Astronomical objects 🔗 Astronomy/Solar System

Vulcan was a theorized planet that some pre-20th century astronomers thought existed in an orbit between Mercury and the Sun. Speculation about, and even purported observations of, intermercurial bodies or planets date back to the beginning of the 17th century. The case for their probable existence was bolstered by the support of the French mathematician Urbain Le Verrier, who had predicted the existence of Neptune using disturbances in the orbit of Uranus. By 1859 he had confirmed unexplained peculiarities in Mercury's orbit and predicted that they had to be the result of the gravitational influence of another unknown nearby planet or series of asteroids. A French amateur astronomer's report that he had observed an object passing in front of the Sun that same year led Le Verrier to announce that the long sought after planet, which he gave the name Vulcan, had been discovered at last.

Many searches were conducted for Vulcan over the following decades, but despite several claimed observations, its existence could not be confirmed. The need for the planet as an explanation for Mercury's orbital peculiarities was later rendered unnecessary when Einstein's 1915 theory of general relativity showed that Mercury's departure from an orbit predicted by Newtonian physics was explained by effects arising from the curvature of spacetime caused by the Sun's mass.

🔗 Computing

The R3000 is a 32-bit RISC microprocessor chipset developed by MIPS Computer Systems that implemented the MIPS I instruction set architecture (ISA). Introduced in June 1988, it was the second MIPS implementation, succeeding the R2000 as the flagship MIPS microprocessor. It operated at 20, 25 and 33.33 MHz.

The MIPS 1 instruction set is small compared to those of the contemporary 80x86 and 680x0 architectures, encoding only more commonly used operations and supporting few addressing modes. Combined with its fixed instruction length and only three different types of instruction formats, this simplified instruction decoding and processing. It employed a 5-stage instruction pipeline, enabling execution at a rate approaching one instruction per cycle, unusual for its time.

This MIPS generation supports up to four co-processors. In addition to the CPU core, the R3000 microprocessor includes a Control Processor (CP), which contains a Translation Lookaside Buffer and a Memory Management Unit. The CP works as a coprocessor. Besides the CP, the R3000 can also support an external R3010 numeric coprocessor and two other external coprocessors.

The R3000 CPU does not include level 1 cache. Instead, its on-chip cache controller operates external data and instruction caches of up to 256 KB each. It can access both caches during the same clock cycle.

The R3000 found much success and was used by many companies in their workstations and servers. Users included:

• Ardent Computer
• Digital Equipment Corporation (DEC) for their DECstation workstations and multiprocessor DECsystem servers
• Evans & Sutherland for their Vision (ESV) series workstations
• MIPS Computer Systems for their MIPS RISC/os Unix workstations and servers.
• NEC for their RISC EWS4800 workstations and UP4800 servers.
• Prime Computer
• Pyramid Technology
• Seiko Epson
• Silicon Graphics for their Professional IRIS, Personal IRIS and Indigo workstations, and the multiprocessor Power Series visualization systems
• Sony for their PlayStation and PlayStation 2 (SCPH-10000 to SCPH-700XX - clocked at 37.5 MHz for use as an I/O CPU and at 33.8 MHz for compatibility with PlayStation games) video game consoles, and NEWS workstations, as well as the Bemani System 573 Analog arcade unit, which runs on the R3000A.
• Tandem Computers for their NonStop Cyclone/R and CLX/R fault-tolerant servers
• Whitechapel Workstations for their Hitech-20 workstation
• New Horizons Probe

The R3000 was also used as an embedded microprocessor. When advances in technology rendered it obsolete for high-performance systems, it found continued use in lower-cost designs. Companies such as LSI Logic developed derivatives of the R3000 specifically for embedded systems.

The R3000 was a further development of the R2000 with minor improvements including larger TLB and a faster bus to the external caches. The R3000 die contained 115,000 transistors and measured about 75,000 square mils (48 mm²). MIPS was a fabless semiconductor company, so the R3000 was fabricated by MIPS partners including Integrated Device Technology (IDT), LSI Logic, NEC Corporation, Performance Semiconductor, and others. It was fabricated in a 1.2 μm complementary metal–oxide–semiconductor (CMOS) process with two levels of aluminium interconnect.

Derivatives of the R3000 for non-embedded applications include:

• R3000A - A further development by MIPS introduced in 1989. It operated at clock frequencies up to 40 MHz.
• PR3400 - Developed by Performance Semiconductor, introduced in May 1991, also at up to 40 MHz. It integrated the Performance Semiconductor PR3000A and PR3010A onto a single die.

Derivatives of the R3000 for embedded applications include:

• PR31700 - A 75 MHz microcontroller from Philips Semiconductors. Fabricated in a 0.35 μm process, delivered in a 208-pin LQFP, it operated at 3.3 V and dissipated only 0.35 W.
• RISController - A family of low-end microcontrollers from IDT. Models include the R3041, R3051, R3052, and R3081.
• TX3900 - A microcontroller from Toshiba.
• Mongoose-V - A radiation-hardened and expanded 10–15 MHz CPU for use on spacecraft, it is still in use today in applications such as NASA's New Horizons space probe.

🔗 United States/U.S. Government 🔗 United States 🔗 Mass surveillance 🔗 Espionage 🔗 California 🔗 California/San Francisco Bay Area 🔗 Telecommunications

Room 641A is a telecommunication interception facility operated by AT&T for the U.S. National Security Agency, as part of its warrantless surveillance program as authorized by the Patriot Act. The facility commenced operations in 2003 and its purpose was publicly revealed in 2006.

🔗 Games

The Hardest Logic Puzzle Ever is a logic puzzle so called by American philosopher and logician George Boolos and published in The Harvard Review of Philosophy in 1996. Boolos' article includes multiple ways of solving the problem. A translation in Italian was published earlier in the newspaper La Repubblica, under the title L'indovinello più difficile del mondo.

It is stated as follows:

Three gods A, B, and C are called, in no particular order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter. Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one god. The gods understand English, but will answer all questions in their own language, in which the words for yes and no are da and ja, in some order. You do not know which word means which.

Boolos provides the following clarifications: a single god may be asked more than one question, questions are permitted to depend on the answers to earlier questions, and the nature of Random's response should be thought of as depending on the flip of a fair coin hidden in his brain: if the coin comes down heads, he speaks truly; if tails, falsely.

🔗 Disaster management 🔗 Ukraine

The Kramatorsk radiological accident was a radiation accident that happened in Kramatorsk, in the Ukrainian SSR from 1980 to 1989. A small capsule containing highly radioactive caesium-137 was found inside the concrete wall of an apartment building, with a surface gamma radiation exposure dose rate of 1800 R/year. The capsule was detected only after residents requested that the level of radiation in the apartment be measured by a health physicist.

The capsule was originally part of a radiation level gauge and was lost in the Karansky quarry in the late 1970s. The search for the capsule was unsuccessful and ended after a week. The gravel from the quarry was used in construction. The caesium capsule ended up in the concrete panel of apartment 85 of building 7 on Mariyi Pryimachenko Street (at the time under the Soviet name Gvardeytsiv Kantemirovtsiv), between apartments 85 and 52.

Over nine years, two families lived in apartment 85. A child's bed was located directly next to the wall containing the capsule. The apartment was fully settled in 1980. A year later, an 18-year-old woman who lived there suddenly died. In 1982, her 16-year-old brother followed, and then their mother. Even after that the flat did not attract much public attention, despite the fact that the residents all died from leukemia. Doctors were unable to determine root-cause of illness and explained the diagnosis by poor heredity. A new family moved into the apartment, and their son died from leukemia as well. His father managed to start a detailed investigation, during which the vial was found in the wall in 1989.

By the time the capsule was discovered, four residents of the building had died from it and 17 more had received varying doses of radiation. Part of the wall was removed and sent to the Institute for Nuclear Research, where the caesium capsule was removed, identified by serial number and disposed of.