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๐Ÿ”— Horizontal Gene Transfer

๐Ÿ”— Molecular and Cell Biology ๐Ÿ”— Microbiology ๐Ÿ”— Genetics ๐Ÿ”— Citizendium Porting ๐Ÿ”— Evolutionary biology

Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between unicellular and/or multicellular organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the evolution of many organisms.

Horizontal gene transfer is the primary mechanism for the spread of antibiotic resistance in bacteria, and plays an important role in the evolution of bacteria that can degrade novel compounds such as human-created pesticides and in the evolution, maintenance, and transmission of virulence. It often involves temperate bacteriophages and plasmids. Genes responsible for antibiotic resistance in one species of bacteria can be transferred to another species of bacteria through various mechanisms of HGT such as transformation, transduction and conjugation, subsequently arming the antibiotic resistant genes' recipient against antibiotics. The rapid spread of antibiotic resistance genes in this manner is becoming medically challenging to deal with. Ecological factors may also play a role in the LGT of antibiotic resistant genes. It is also postulated that HGT promotes the maintenance of a universal life biochemistry and, subsequently, the universality of the genetic code.

Most thinking in genetics has focused upon vertical transfer, but the importance of horizontal gene transfer among single-cell organisms is beginning to be acknowledged.

Gene delivery can be seen as an artificial horizontal gene transfer, and is a form of genetic engineering.

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๐Ÿ”— Mellified man

๐Ÿ”— Death ๐Ÿ”— Agriculture ๐Ÿ”— China ๐Ÿ”— Skepticism ๐Ÿ”— Alternative medicine ๐Ÿ”— Arab world ๐Ÿ”— Agriculture/Beekeeping

A mellified man, or a human mummy confection, was a legendary medicinal substance created by steeping a human cadaver in honey. The concoction is detailed in Chinese medical sources, most significantly the Bencao Gangmu of the 16th-century Chinese medical doctor and pharmacologist Li Shizhen. Relying on a second-hand account, Li reports a story that some elderly men in Arabia, nearing the end of their lives, would submit themselves to a process of mummification in honey to create a healing confection.

This process differed from a simple body donation because of the aspect of self-sacrifice; the mellification process would ideally start before death. The donor would stop eating any food other than honey, going as far as to bathe in the substance. Shortly, his feces (and even his sweat, according to legend) would consist of honey. When this diet finally proved fatal, the donor's body would be placed in a stone coffin filled with honey.

After a century or so, the contents would have turned into a sort of confection reputedly capable of healing broken limbs and other ailments. This confection would then be sold in street markets as a hard to find item with a hefty price.

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๐Ÿ”— OS-9: real-time, multi-user, Unix-like OS developed in the 1980s

๐Ÿ”— Computing

OS-9 is a family of real-time, process-based, multitasking, multi-user operating systems, developed in the 1980s, originally by Microware Systems Corporation for the Motorola 6809 microprocessor. It was purchased by Radisys Corp in 2001, and was purchased again in 2013 by its current owner Microware LP.

The OS-9 family was popular for general-purpose computing and remains in use in commercial embedded systems and amongst hobbyists. Today, OS-9 is a product name used by both a Motorola 68000-series machine language OS and a portable (PowerPC, x86, ARM, MIPS, SH4, etc.) version written in C, originally known as OS-9000.

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๐Ÿ”— Top 500 supercomputers by processor family

๐Ÿ”— Technology ๐Ÿ”— Computing ๐Ÿ”— Electronics

A supercomputer is a computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second (FLOPS) instead of million instructions per second (MIPS). Since 2017, there are supercomputers which can perform over a hundred quadrillion FLOPS (petaFLOPS). Since November 2017, all of the world's fastest 500 supercomputers run Linux-based operating systems. Additional research is being conducted in China, the United States, the European Union, Taiwan and Japan to build faster, more powerful and technologically superior exascale supercomputers.

Supercomputers play an important role in the field of computational science, and are used for a wide range of computationally intensive tasks in various fields, including quantum mechanics, weather forecasting, climate research, oil and gas exploration, molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), and physical simulations (such as simulations of the early moments of the universe, airplane and spacecraft aerodynamics, the detonation of nuclear weapons, and nuclear fusion). They have been essential in the field of cryptanalysis.

Supercomputers were introduced in the 1960s, and for several decades the fastest were made by Seymour Cray at Control Data Corporation (CDC), Cray Research and subsequent companies bearing his name or monogram. The first such machines were highly tuned conventional designs that ran faster than their more general-purpose contemporaries. Through the decade, increasing amounts of parallelism were added, with one to four processors being typical. From the 1970s, vector processors operating on large arrays of data came to dominate. A notable example is the highly successful Cray-1 of 1976. Vector computers remained the dominant design into the 1990s. From then until today, massively parallel supercomputers with tens of thousands of off-the-shelf processors became the norm.

The US has long been the leader in the supercomputer field, first through Cray's almost uninterrupted dominance of the field, and later through a variety of technology companies. Japan made major strides in the field in the 1980s and 90s, with China becoming increasingly active in the field. As of November 2018, the fastest supercomputer on the TOP500 supercomputer list is the Summit, in the United States, with a LINPACK benchmark score of 143.5ย PFLOPS, followed by, Sierra, by around 48.860ย PFLOPS. The US has five of the top 10 and China has two. In June 2018, all supercomputers on the list combined broke the 1 exaFLOPS mark.

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๐Ÿ”— A man died yesterday. He had a huge impact on our lives. Fred Shuttlesworth.

๐Ÿ”— United States ๐Ÿ”— Biography ๐Ÿ”— African diaspora ๐Ÿ”— United States/Ohio ๐Ÿ”— United States/Cincinnati ๐Ÿ”— Civil Rights Movement ๐Ÿ”— Alabama

Frederick Lee "Fred" Shuttlesworth (born Fred Lee Robinson, March 18, 1922 โ€“ October 5, 2011) was a U.S. civil rights activist who led the fight against segregation and other forms of racism as a minister in Birmingham, Alabama. He was a co-founder of the Southern Christian Leadership Conference, initiated and was instrumental in the 1963 Birmingham Campaign, and continued to work against racism and for alleviation of the problems of the homeless in Cincinnati, Ohio, where he took up a pastorate in 1961. He returned to Birmingham after his retirement in 2007. He helped Martin Luther King Jr. during the civil rights movement.

The Birminghamโ€“Shuttlesworth International Airport was named in his honor in 2008.

The Birmingham Civil Rights Institute Fred L. Shuttlesworth Human Rights Award is bestowed annually in his name.

๐Ÿ”— Turboencabulator

๐Ÿ”— Engineering

The turboencabulator or turbo-encabulator (and its later incarnations, the retroencabulator or retro-encabulator and Micro Encabulator) is a fictional machine whose alleged existence became an in-joke and subject of professional humor among engineers. The explanation of the supposed product makes extensive use of technobabble.

The gag was popular for many years. The following quote is from the original Students' Quarterly Journal article written by J. H. Quick in 1944. The citation in the later Time article misspells several of the technical terms. General Electric, Chrysler and Rockwell Automation use many of the same words.

The original machine had a base plate of prefabulated amulite, surmounted by a malleable logarithmic casing in such a way that the two main spurving bearings were in a direct line with the panametric fan. The latter consisted simply of six hydrocoptic marzlevanes, so fitted to the ambifacient lunar waneshaft that side fumbling was effectively prevented. The main winding was of the normal lotus-o-deltoid type placed in panendermic semi-boloid slots in the stator, every seventh conductor being connected by a nonreversible tremmie pipe to the differential girdlespring on the "up" end of the grammeters.

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๐Ÿ”— Rhythm 0

๐Ÿ”— Visual arts

Rhythm 0 was a six-hour work of performance art by Serbian artist Marina Abramoviฤ‡ in Naples in 1974. The work involved Abramoviฤ‡ standing still while the audience was invited to do to her whatever they wished, using one of 72 objects she had placed on a table. These included a rose, feather, perfume, honey, bread, grapes, wine, scissors, a scalpel, nails, a metal bar, a gun, and a bullet.

There were no separate stages. Abramoviฤ‡ and the visitors stood in the same space, making it clear that the latter were part of the work. The purpose of the piece, she said, was to find out how far the public would go: "What is the public about and what are they going to do in this kind of situation?"

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๐Ÿ”— Credit Unions

๐Ÿ”— Finance & Investment ๐Ÿ”— Economics ๐Ÿ”— Business ๐Ÿ”— Cooperatives

A credit union, a type of financial institution similar to a commercial bank, is a member-owned nonprofit financial cooperative. Credit unions generally provide services to members similar to retail banks, including deposit accounts, provision of credit, and other financial services. In several African countries, credit unions are commonly referred to as SACCOs (Savings and Credit Co-Operatives).

Worldwide, credit union systems vary significantly in their total assets and average institution asset size, ranging from volunteer operations with a handful of members to institutions with hundreds of thousands of members and assets worth billions of US dollars. In 2018, the number of members in credit unions worldwide was 274 million, with nearly 40ย million members having been added since 2016.

Leading up to the financial crisis of 2007โ€“2008, commercial banks engaged in approximately five times more subprime lending relative to credit unions and were two and a half times more likely to fail during the crisis. American credit unions more than doubled lending to small businesses between 2008 and 2016, from $30ย billion to $60ย billion, while lending to small businesses overall during the same period declined by around $100ย billion. In the US, public trust in credit unions stands at 60%, compared to 30% for big banks. Furthermore, small businesses are 80% less likely to be dissatisfied with a credit union than with a big bank.

"Natural-person credit unions" (also called "retail credit unions" or "consumer credit unions") serve individuals, as distinguished from "corporate credit unions", which serve other credit unions.

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๐Ÿ”— Tuffi

๐Ÿ”— Mammals

Tuffi (born 1946, India โ€“ died 1989, Paris, France) was a female Asian elephant that became famous in West Germany during 1950 when she accidentally fell from the Wuppertal Schwebebahn into the River Wupper underneath.

On 21 July 1950, the circus director Franz Althoff (de) had Tuffi, then four years old, traveled on the suspended monorail in Wuppertal, as a publicity stunt. The elephant trumpeted wildly and ran through the carriage, broke through a window and fell 12 metres (39ย ft) down into the River Wupper, suffering only minor injuries. A panic had broken out in the carriage and some passengers were injured. Althoff helped the elephant out of the water. Both the circus director and the official who had allowed the ride were fined. Tuffi was sold to Cirque Alexis Gruss (fr) in 1968; she died there in 1989.

No photograph of the incident is known; a widely circulated postcard picture is a montage. A building near the location of the incident, between the stations Alter Markt and Adlerbrรผcke, features a painting of Tuffi. A local milk-factory has chosen the name as a brand.

The Wuppertal tourist information keeps an assortment of Tuffi-related souvenirs, local websites show original pictures.

In 1970 Marguerita Eckel and Ernst-Andreas Ziegler published a children's picture book about the incident titled Tuffi und die Schwebebahn (โ€œTuffi and the suspension railwayโ€).

๐Ÿ”— Quine

๐Ÿ”— Computing

A quine is a computer program which takes no input and produces a copy of its own source code as its only output. The standard terms for these programs in the computability theory and computer science literature are "self-replicating programs", "self-reproducing programs", and "self-copying programs".

A quine is a fixed point of an execution environment, when the execution environment is viewed as a function transforming programs into their outputs. Quines are possible in any Turing complete programming language, as a direct consequence of Kleene's recursion theorem. For amusement, programmers sometimes attempt to develop the shortest possible quine in any given programming language.

The name "quine" was coined by Douglas Hofstadter, in his popular science book Gรถdel, Escher, Bach, in honor of philosopher Willard Van Orman Quine (1908โ€“2000), who made an extensive study of indirect self-reference, and in particular for the following paradox-producing expression, known as Quine's paradox:

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

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