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๐Ÿ”— List of Leaf Vegetables

๐Ÿ”— Lists ๐Ÿ”— Food and drink ๐Ÿ”— Plants

This is a list of vegetables which are grown or harvested primarily for the consumption of their leafy parts, either raw or cooked. Many plants with leaves that are consumed in small quantities as a spice such as oregano, for medicinal purposes such as lime, or used in infusions such as tea, are not included in this list.

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๐Ÿ”— Type I and type II errors

๐Ÿ”— Mathematics ๐Ÿ”— Statistics

In statistical hypothesis testing, a type I error is the rejection of a true null hypothesis (also known as a "false positive" finding or conclusion), while a type II error is the non-rejection of a false null hypothesis (also known as a "false negative" finding or conclusion). Much of statistical theory revolves around the minimization of one or both of these errors, though the complete elimination of either is a statistical impossibility for non-deterministic algorithms. By selecting a low threshold (cut-off) value and modifying the alpha (p) level, the quality of the hypothesis test can be increased. The knowledge of Type I errors and Type II errors is widely used in medical science, biometrics and computer science.

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๐Ÿ”— Abelian sandpile model

๐Ÿ”— Mathematics ๐Ÿ”— Physics ๐Ÿ”— Systems ๐Ÿ”— Systems/Dynamical systems

The Abelian sandpile model, also known as the Bakโ€“Tangโ€“Wiesenfeld model, was the first discovered example of a dynamical system displaying self-organized criticality. It was introduced by Per Bak, Chao Tang and Kurt Wiesenfeld in a 1987 paper.

The model is a cellular automaton. In its original formulation, each site on a finite grid has an associated value that corresponds to the slope of the pile. This slope builds up as "grains of sand" (or "chips") are randomly placed onto the pile, until the slope exceeds a specific threshold value at which time that site collapses transferring sand into the adjacent sites, increasing their slope. Bak, Tang, and Wiesenfeld considered process of successive random placement of sand grains on the grid; each such placement of sand at a particular site may have no effect, or it may cause a cascading reaction that will affect many sites.

The model has since been studied on the infinite lattice, on other (non-square) lattices, and on arbitrary graphs (including directed multigraphs). It is closely related to the dollar game, a variant of the chip-firing game introduced by Biggs.

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๐Ÿ”— Hyperion (Tree)

๐Ÿ”— California ๐Ÿ”— Plants

Hyperion is a coast redwood (Sequoia sempervirens) in California that is the world's tallest known living tree, measured at 116.07 metres (380.8ย ft) tall in 2019.

Hyperion was discovered on Augustย 25, 2006, by naturalists Chris Atkins and Michael Taylor. The tree height of 115.55ย m (379.1ย ft) was verified by Stephen Sillett in 2006 using both a laser range finder and a fiberglass tape to measure the tree from the base to the crown. The tree has grown since then to reach 116.07 metres (380.8ย ft) recorded in 2019. Hyperion was found in a remote area of Redwood National Park, inside of the originally designated park boundaries of 1968. The park also houses the second-, fourth- and fifth-tallest known trees, coast redwoods named Helios, Icarus, and Daedalus, which respectively measured 377, 371 and 363 feet in 2022.

The tree was named after the titan Hyperion from Greek mythology.

Hyperion is estimated to be between 600 and 800 years old and contain 530ย m3 (18,600ย cuย ft) of wood.

The exact location of Hyperion is nominally secret but is available via internet search. However, in Julyย 2022, the Redwood Park superintendent closed the entire area around the tree, citing "devastation of the habitat surrounding Hyperion" caused by visitors. Its base was trampled by the overuse and as a result ferns no longer grow around the tree. Anyone who gets too close could face up to six months in jail and a $5,000 maximum fine.

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๐Ÿ”— Operation Serenata de Amor โ€“ An AI project to analyze public spending in Brazil

๐Ÿ”— Science

Operation Serenata de Amor is an artificial intelligence project to analyze public spending in Brazil. The project has been funded by a recurrent financing campaign since September 7, 2016, and came in the wake of major scandals of misappropriation of public funds in Brazil, such as the Mensalรฃo scandal and what was revealed in the Operation Car Wash investigations.

The analysis began with data from the National Congress and then expanded to other types of budget and other instances of government, such as the Federal Senate. The project is built through collaboration on GitHub and using a public group with more than 600 participants on Telegram.

The name "Serenata de Amor," which means "serenade of love," was taken from a popular cashew cream bonbon produced by Chocolates Garoto in Brazil.

๐Ÿ”— The Centipedeโ€™s Dilemma

๐Ÿ”— Psychology ๐Ÿ”— Poetry

"The Centipede's Dilemma" is a short poem that has lent its name to a psychological effect called the centipede effect or centipede syndrome. The centipede effect occurs when a normally automatic or unconscious activity is disrupted by consciousness of it or reflection on it. For example, a golfer thinking too closely about their swing or someone thinking too much about how they knot their tie may find their performance of the task impaired. The effect is also known as hyperreflection or Humphrey's law after English psychologist George Humphrey (1889โ€“1966), who propounded it in 1923. As he wrote of the poem, "This is a most psychological rhyme. It contains a profound truth which is illustrated daily in the lives of all of us". The effect is the reverse of a solvitur ambulando.

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๐Ÿ”— Turbo Button

๐Ÿ”— Video games ๐Ÿ”— Computing

On personal computers, the turbo button is a button which provides two run states for the computer: normal speed or an enhanced "turbo" speed. It was relatively common on personal computers using the Intel 80286, Intel 80386 and Intel 80486 processors, from the mid 1980s to mid 1990s.

The name is inspired by turbocharger, a turbine-driven forced induction device that increases an engine's power and efficiency.

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๐Ÿ”— An example of quantum-hard classically-implementable asymmetric crypto

๐Ÿ”— Cryptography ๐Ÿ”— Cryptography/Computer science

NTRU is an open source public-key cryptosystem that uses lattice-based cryptography to encrypt and decrypt data. It consists of two algorithms: NTRUEncrypt, which is used for encryption, and NTRUSign, which is used for digital signatures. Unlike other popular public-key cryptosystems, it is resistant to attacks using Shor's algorithm and its performance has been shown to be significantly better. NTRU was patented but was placed in public domain in 2017, and can be used by software under the GPL.

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๐Ÿ”— Maillard reaction

๐Ÿ”— Food and drink ๐Ÿ”— Chemistry

The Maillard reaction ( my-YAR; French:ย [majaส]) is a chemical reaction between amino acids and reducing sugars that gives browned food its distinctive flavor. Seared steaks, fried dumplings, cookies and other kinds of biscuits, breads, toasted marshmallows, and many other foods undergo this reaction. It is named after French chemist Louis-Camille Maillard, who first described it in 1912 while attempting to reproduce biological protein synthesis.

The reaction is a form of non-enzymatic browning which typically proceeds rapidly from around 140 to 165ย ยฐC (280 to 330ย ยฐF). Many recipes call for an oven temperature high enough to ensure that a Maillard reaction occurs. At higher temperatures, caramelization (the browning of sugars, a distinct process) and subsequently pyrolysis (final breakdown leading to burning) become more pronounced.

The reactive carbonyl group of the sugar reacts with the nucleophilic amino group of the amino acid, and forms a complex mixture of poorly characterized molecules responsible for a range of aromas and flavors. This process is accelerated in an alkaline environment (e.g., lye applied to darken pretzels; see lye roll), as the amino groups (RNH3+ โ†’ RNH2) are deprotonated, and hence have an increased nucleophilicity. This reaction is the basis for many of the flavoring industry's recipes. At high temperatures, a probable carcinogen called acrylamide can form. This can be discouraged by heating at a lower temperature, adding asparaginase, or injecting carbon dioxide.

In the cooking process, Maillard reactions can produce hundreds of different flavor compounds depending on the chemical constituents in the food, the temperature, the cooking time, and the presence of air. These compounds, in turn, often break down to form yet more new flavor compounds. Flavor scientists have used the Maillard reaction over the years to make artificial flavors.

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๐Ÿ”— Run Commands, the 'rc' in '.bashrc'

๐Ÿ”— Software ๐Ÿ”— Software/Computing

In the context of Unix-like systems, the term rc stands for the phrase "run commands". It is used for any file that contains startup information for a command. It is believed to have originated sometime in 1965 at a runcom facility from the MIT Compatible Time-Sharing System (CTSS).

From Brian Kernighan and Dennis Ritchie:

There was a facility that would execute a bunch of commands stored in a file; it was called runcom for "run commands", and the file began to be called "a runcom". rc in Unix is a fossil from that usage.

Tom Van Vleck, a Multics engineer, has also reminisced about the extension rc: "The idea of having the command processing shell be an ordinary slave program came from the Multics design, and a predecessor program on CTSS by Louis Pouzin called RUNCOM, the source of the '.rc' suffix on some Unix configuration files."

This is also the origin of the name of the Plan 9 from Bell Labs shell by Tom Duff, the rc shell. It is called "rc" because the main job of a shell is to "run commands".

While not historically precise, rc may also be expanded as "run control", because an rc file controls how a program runs. For instance, the editor Vim looks for and reads the contents of the .vimrc file to determine its initial configuration. In The Art of Unix Programming, Eric S. Raymond consistently refers to rc files as "run-control" files.

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