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π Al-Jazari
BadΔ«ΚΏ az-Zaman Abu l-ΚΏIzz ibn IsmΔΚΏΔ«l ibn ar-RazΔz al-JazarΔ« (1136β1206, Arabic: Ψ¨Ψ―ΩΨΉ Ψ§ΩΨ²Ω Ψ§Ω Ψ£ΩΨ¨Ω Ψ§ΩΩΩΨΉΩΨ²Ω Ψ₯Ψ¨ΩΩΩ Ψ₯Ψ³ΩΩ Ψ§ΨΉΩΩΩΩ Ψ₯Ψ¨ΩΩΩ Ψ§ΩΨ±ΩΩΨ²Ψ§Ψ² Ψ§ΩΨ¬Ψ²Ψ±Ωβ, IPA:Β [Γ¦ldΚΓ¦zΓ¦riΛ]) was a Muslim polymath: a scholar, inventor, mechanical engineer, artisan, artist and mathematician. He is best known for writing The Book of Knowledge of Ingenious Mechanical Devices (Arabic: ΩΨͺΨ§Ψ¨ ΩΩ Ω ΨΉΨ±ΩΨ© Ψ§ΩΨΩΩ Ψ§ΩΩΩΨ―Ψ³ΩΨ©β, romanized:Β Kitab fi ma'rifat al-hiyal al-handasiya, lit.Β 'Book in knowledge of engineering tricks') in 1206, where he described 100 mechanical devices, some 80 of which are trick vessels of various kinds, along with instructions on how to construct them.
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- "Al-Jazari" | 2014-09-07 | 286 Upvotes 122 Comments
π Don't Mess with Texas
Don't Mess with Texas is a slogan for a campaign aimed at reducing littering on Texas roadways by the Texas Department of Transportation. The phrase "Don't Mess with Texas" is prominently shown on road signs on major highways, television, radio and in print advertisements. The campaign is credited with reducing litter on Texas highways roughly 72% between 1987 and 1990. The campaign's target market was 18- to 35-year-old males, which was statistically shown to be the most likely to litter. While the slogan was not originally intended to become a statewide cultural phenomenon, it did.
Beyond its immediate role in reducing litter, the slogan has been popularly appropriated by Texans. The phrase has become "an identity statement, a declaration of Texas swagger". Though the origin of the slogan is not well known outside of Texas, it appears on countless items of tourist souvenirs. Since the phrase is a federally registered trademark, the department has tried at times to enforce its trademark rights with cease and desist letters, but has had very limited success. The slogan is the title of the book, Donβt Mess With Texas: The Story Behind the Legend.
"Don't Mess with Texas" has been awarded a plaque on the Madison Avenue Walk of Fame and a place in the Advertising Hall of Fame, a distinction given to only two slogans annually.
"Don't Mess with Texas" is also the official motto of the Virginia-class submarine USS Texas.
In 2011 the result of a public vote for the best "Don't Mess with Texas" ad over the last 25 was revealed, the winner was one created by the Commemorative Air Force (then called the Confederate Air Force). The ad involved the CAF's Boeing B-17 "Sentimental Journey" pursuing and retaliating against a truck from which trash was thrown.
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- "Don't Mess with Texas" | 2020-04-21 | 218 Upvotes 190 Comments
π Bradley Manning leaked Granai Airstrike "~86-147, mostly women and children"
The Granai airstrike, sometimes called the Granai massacre, refers to the killing of approximately 86 to 147 Afghan civilians by an airstrike by a US Air Force B-1 Bomber on May 4, 2009, in the village of Granai (sometimes spelled Garani or Gerani) in Farah Province, south of Herat, Afghanistan.
The United States admitted significant errors were made in carrying out the airstrike, stating "the inability to discern the presence of civilians and avoid and/or minimize accompanying collateral damage resulted in the unintended consequence of civilian casualties".
The Afghan government has said that around 140 civilians were killed, of whom 22 were adult males and 93 were children. Afghanistan's top rights body has said 97 civilians were killed, most of them children. Other estimates range from 86 to 147 civilians killed. An earlier probe by the US military had said that 20β30 civilians were killed along with 60β65 insurgents. A partially released American inquiry stated "no one will ever be able conclusively to determine the number of civilian casualties that occurred". The Australian has said that the airstrike resulted in "one of the highest civilian death tolls from Western military action since foreign forces invaded Afghanistan in 2001".
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- "Bradley Manning leaked Granai Airstrike "~86-147, mostly women and children"" | 2013-06-08 | 233 Upvotes 173 Comments
π Ant mill
An ant mill is an observed phenomenon in which a group of army ants are separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle, commonly known as a "death spiral" because the ants might eventually die of exhaustion. It has been reproduced in laboratories and has been produced in ant colony simulations. The phenomenon is a side effect of the self-organizing structure of ant colonies. Each ant follows the ant in front of it, which works until a slight deviation begins to occur, typically by an environmental trigger, and an ant mill forms. An ant mill was first described in 1921 by William Beebe, who observed a mill 1200Β ft (~370 m) in circumference. It took each ant 2.5 hours to make one revolution. Similar phenomena have been noted in processionary caterpillars and fish.
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- "Ant mill" | 2022-01-22 | 251 Upvotes 154 Comments
π Ramanujan's Lost Notebook
Ramanujan's lost notebook is the manuscript in which the Indian mathematician Srinivasa Ramanujan recorded the mathematical discoveries of the last year (1919β1920) of his life. Its whereabouts were unknown to all but a few mathematicians until it was rediscovered by George Andrews in 1976, in a box of effects of G. N. Watson stored at the Wren Library at Trinity College, Cambridge. The "notebook" is not a book, but consists of loose and unordered sheets of paper described as "more than one hundred pages written on 138 sides in Ramanujan's distinctive handwriting. The sheets contained over six hundred mathematical formulas listed consecutively without proofs."
George Andrews and Bruce C. BerndtΒ (2005, 2009, 2012, 2013, 2018) have published several books in which they give proofs for Ramanujan's formulas included in the notebook. Berndt says of the notebook's discovery: "The discovery of this 'Lost Notebook' caused roughly as much stir in the mathematical world as the discovery of Beethovenβs tenth symphony would cause in the musical world."
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- "Ramanujan's Lost Notebook" | 2024-04-15 | 306 Upvotes 94 Comments
π Black Start
A black start is the process of restoring an electric power station or a part of an electric grid to operation without relying on the external electric power transmission network to recover from a total or partial shutdown.
Normally, the electric power used within the plant is provided from the station's own generators. If all of the plant's main generators are shut down, station service power is provided by drawing power from the grid through the plant's transmission line. However, during a wide-area outage, off-site power from the grid is not available. In the absence of grid power, a so-called black start needs to be performed to bootstrap the power grid into operation.
To provide a black start, some power stations have small diesel generators, normally called the black start diesel generator (BSDG), which can be used to start larger generators (of several megawatts capacity), which in turn can be used to start the main power station generators. Generating plants using steam turbines require station service power of up to 10% of their capacity for boiler feedwater pumps, boiler forced-draft combustion air blowers, and for fuel preparation. It is uneconomical to provide such a large standby capacity at each station, so black-start power must be provided over designated tie lines from another station. Often hydroelectric power plants are designated as the black-start sources to restore network interconnections. A hydroelectric station needs very little initial power for starting purposes (just enough to open the intake gates and provide excitation current to the generator field coils), and can put a large block of power on line very quickly to allow start-up of fossil-fuel or nuclear stations. Certain types of combustion turbine can be configured for black start, providing another option in places without suitable hydroelectric plants. In 2017, a utility in Southern California successfully demonstrated the use of a battery-based energy-storage system to provide a black start, firing up a combined-cycle gas turbine from an idle state.
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- "Black Start" | 2013-04-29 | 289 Upvotes 105 Comments
π Massachusetts Right to Repair Initiative
The Massachusetts "Right to Repair" Initiative, also known as Question 1, appeared on the Massachusetts 2012 general election ballot as an initiated state statute. The Right to Repair proposal was to require vehicle owners and independent repair facilities in Massachusetts to have access to the same vehicle diagnostic and repair information made available to the manufacturers' Massachusetts dealers and authorized repair facilities. The initiative passed with overwhelming voter support on November 6, 2012, with 86% for and 14% against. The measure, originally filed four times with the Massachusetts Attorney General, was filed by Arthur W. Kinsman, and was assigned initiative numbers 11-17.
2019 Ballot Initiative In early 2019 the Massachusetts Legislature submitted bills advocating change to close loopholes associated with wireless transmission of diagnostic information. Advocates supporting an update to the Massachusetts Right to Repair law have announced that the required signatures have been gathered to place Right to Repair on the November 3, 2020 ballot.
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- "Massachusetts Right to Repair Initiative" | 2016-04-04 | 264 Upvotes 128 Comments
π Norsk Data
Norsk Data was a (mini-)computer manufacturer located in Oslo, Norway. Existing from 1967 to 1992, it had its most active period in the years from the early 1970s to the late 1980s. At the company's peak in 1987 it was the second largest company in Norway and employed over 4,500 people.
Throughout its history Norsk Data produced a long string of extremely innovative systems, with a disproportionately large number of world firsts. Some examples of this are the NORD-1, the first minicomputer to have memory paging as a standard option, and the first machine to have floating-point instructions standard, the NORD-5, the world's first 32-bit minicomputer (beating the VAX, often claimed the first, by 6 years)
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- "Norsk Data" | 2020-05-06 | 301 Upvotes 91 Comments
π HeLa, the oldest and most commonly used human cell line
HeLa (; also Hela or hela) is an immortal cell line used in scientific research. It is the oldest and most commonly used human cell line. The line was derived from cervical cancer cells taken on February 8, 1951 from Henrietta Lacks, a patient who died of cancer on October 4, 1951. The cell line was found to be remarkably durable and prolific, which gives rise to its extensive use in scientific research.
The cells from Lacks's cancerous cervical tumor were taken without her knowledge or consent, which was common practice at the time. Cell biologist George Otto Gey found that they could be kept alive, and developed a cell line. Previously, cells cultured from other human cells would only survive for a few days. Scientists would spend more time trying to keep the cells alive than performing actual research on them. Cells from Lacks' tumor behaved differently. As was custom for Gey's lab assistant, she labeled the culture 'HeLa', the first two letters of the patient's first and last name; this became the name of the cell line.
These were the first human cells grown in a lab that were naturally "immortal", meaning that they do not die after a set number of cell divisions (i.e. cellular senescence). These cells could be used for conducting a multitude of medical experimentsβif the cells died, they could simply be discarded and the experiment attempted again on fresh cells from the culture. This represented an enormous boon to medical and biological research, as previously stocks of living cells were limited and took significant effort to culture.
The stable growth of HeLa enabled a researcher at the University of Minnesota hospital to successfully grow polio virus, enabling the development of a vaccine, and by 1952, Jonas Salk developed a vaccine for polio using these cells. To test Salk's new vaccine, the cells were put into mass production in the first-ever cell production factory.
In 1953, HeLa cells were the first human cells successfully cloned and demand for the HeLa cells quickly grew in the nascent biomedical industry. Since the cells' first mass replications, they have been used by scientists in various types of investigations including disease research, gene mapping, effects of toxic substances on organisms, and radiation on humans. Additionally, HeLa cells have been used to test human sensitivity to tape, glue, cosmetics, and many other products.
Scientists have grown an estimated 50 million metricΒ tons of HeLa cells, and there are almost 11,000Β patents involving these cells.
The HeLa cell lines are also notorious for invading other cell cultures in laboratory settings. Some have estimated that HeLa cells have contaminated 10β20% of all cell lines currently in use.
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- "HeLa, the oldest and most commonly used human cell line" | 2015-10-30 | 54 Upvotes 12 Comments
- "Immortal cells of Henrietta Lacks" | 2010-02-01 | 36 Upvotes 7 Comments
π Dead Internet Theory
The dead Internet theory is a theory that asserts that the Internet now consists almost entirely of bot activity and automatically generated content, marginalizing human activity. The date given for this "death" is generally around 2016 or 2017.
In 2012, YouTube removed billions of video views from major record labels, such as Sony and Universal, as a result of discovering that they had used fraudulent services to artificially increase the views of their content. The removal of the inflated views aimed to restore credibility to the platform and improve the accuracy of view counts. The move by YouTube also signaled a change in the way the platform would tackle fake views and bot traffic.
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- "Dead Internet Theory" | 2024-09-28 | 14 Upvotes 2 Comments
- "Dead Internet Theory" | 2024-07-12 | 11 Upvotes 3 Comments
- "Dead Internet Theory" | 2023-03-16 | 51 Upvotes 48 Comments