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πŸ”— Sixel: A terminal bitmap graphics format from the 80s

πŸ”— Computing πŸ”— Computing/Software

Sixel, short for "six pixels", is a bitmap graphics format supported by terminals and printers from DEC. It consists of a pattern six pixels high and one wide, resulting in 64 possible patterns. Each possible pattern is assigned an ASCII character, making the sixels easy to transmit on 7-bit serial links.

Sixel was first introduced as a way of sending bitmap graphics to DEC dot matrix printers like the LA50. After being put into "sixel mode" the following data was interpreted to directly control six of the pins in the nine-pin print head. A string of sixel characters encodes a single 6-pixel high row of the image.

The system was later re-used as a way to send bitmap data to the VT200 series and VT320 terminals when defining custom character sets. A series of sixels are used to transfer the bitmap for each character. This feature is known as soft character sets or dynamically redefinable character sets (DRCS). With the VT240, VT241, VT330, and VT340, the terminals could decode a complete sixel image to the screen, like those previously sent to printers.

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πŸ”— Toxic squash syndrome

πŸ”— Chemicals πŸ”— Plants

Cucurbitacin is a class of biochemical compounds that some plants – notably members of the pumpkin and gourd family, Cucurbitaceae – produce and which function as a defence against herbivores. Cucurbitacins are chemically classified as triterpenes, formally derived from cucurbitane, a triterpene hydrocarbon – specifically, from the unsaturated variant cucurbit-5-ene, or 19(10β†’9Ξ²)-abeo-10Ξ±-lanost-5-ene. They often occur as glycosides. They and their derivatives have been found in many plant families (including Brassicaceae, Cucurbitaceae, Scrophulariaceae, Begoniaceae, Elaeocarpaceae, Datiscaceae, Desfontainiaceae, Polemoniaceae, Primulaceae, Rubiaceae, Sterculiaceae, Rosaceae, and Thymelaeaceae), in some mushrooms (including Russula and Hebeloma) and even in some marine mollusks.

Cucurbitacins may be a taste deterrent in plants foraged by some animals and in some edible plants preferred by humans, like cucumbers and zucchinis. In laboratory research, cucurbitacins have cytotoxic properties and are under study for their potential biological activities.

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πŸ”— Old Person Smell

πŸ”— Medicine πŸ”— Ageing and culture

Old person smell is the characteristic odor of elderly humans. Much like many animal species, human odor undergoes distinct stages based on chemical changes initiated through the aging process. Research suggests that this enables humans to determine the suitability of potential partners based on age, in addition to other factors.

One study suggested that old person smell may be the result of 2-nonenal, an unsaturated aldehyde which is associated with human body odor alterations during aging; however, there are other hypotheses. Another study failed to detect 2-nonenal at all, but found significantly increased concentrations of benzothiazole, dimethylsulphone, and nonanal on older subjects.

In 2012 the Monell Chemical Senses Center published a press release claiming that the human ability to identify information such as age, illness, and genetic suitability from odor is responsible for the distinctive "old man smell". Sensory neuroscientist Johan LundstrΓΆm stated, "Elderly people have a discernible underarm odor that younger people consider to be fairly neutral and not very unpleasant."

Old person smell is known as kareishΕ« (εŠ ι½’θ‡­) in Japan, where much social value is placed on personal grooming, and specific upmarket odor-eliminating soaps are targeted at more elderly consumers.

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πŸ”— Flow

πŸ”— Video games πŸ”— Psychology

In positive psychology, a flow state, also known colloquially as being in the zone, is the mental state in which a person performing an activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the process of the activity. In essence, flow is characterized by the complete absorption in what one does, and a resulting transformation in one's sense of time.

Named by MihΓ‘ly CsΓ­kszentmihΓ‘lyi in 1975, the concept has been widely referred to across a variety of fields (and is particularly well recognized in occupational therapy), though the concept has been claimed to have existed for thousands of years under other names, notably in some Eastern thought systems, for example, Daoism and Buddhism.

The flow state shares many characteristics with hyperfocus. However, hyperfocus is not always described in a positive light. Some examples include spending "too much" time playing video games or watching television and getting side-tracked and pleasurably absorbed by one aspect of an assignment or task to the detriment of the overall assignment. In some cases, hyperfocus can "capture" a person, perhaps causing them to appear unfocused or to start several projects, but complete few. Other related concepts are trance, hypnosis, hypomania and mindfulness.

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  • "Flow" | 2010-02-19 | 98 Upvotes 29 Comments

πŸ”— Stalin Note

πŸ”— Soviet Union πŸ”— Russia πŸ”— History πŸ”— Germany πŸ”— Politics πŸ”— Cold War πŸ”— European history

The Stalin Note, also known as the March Note, was a document delivered to the representatives of the Western Allies (the United Kingdom, France, and the United States) from the Soviet Union in Germany on 10 March 1952. Soviet general secretary and premier Joseph Stalin put forth a proposal for a German reunification and neutralisation with no conditions on economic policies and with guarantees for "the rights of man and basic freedoms, including freedom of speech, press, religious persuasion, political conviction, and assembly" and free activity of democratic parties and organizations.

James Warburg, a member of the United States Senate Committee on Foreign Relations, testified before the committee on 28 March 1952 and observed that the Soviet proposal might be a bluff, but he thought that it seemed "that our government is afraid to call the bluff for the fear that it may not be a bluff at all" and might lead to "a free, neutral, and demilitarised Germany", which might be "subverted into Soviet orbit". That led to an exchange of notes between the West and the Soviet Union, which eventually ended after the West had insistence for a unified Germany to be free to join the European Defence Community and to be rearmed, demands that Stalin rejected.

West German Chancellor Konrad Adenauer and the Western Allies characterised Stalin's move as an aggressive action that attempted to stall the reintegration of West Germany. However, there was later a debate on whether a chance for reunification had been missed. Six years after the exchange, two West German ministers, Thomas Dehler and Gustav Heinemann, blamed Adenauer for not having explored the chance of reunification.

πŸ”— BB84 – A quantum key distribution scheme

πŸ”— Cryptography πŸ”— Cryptography/Computer science

BB84 is a quantum key distribution scheme developed by Charles Bennett and Gilles Brassard in 1984. It is the first quantum cryptography protocol. The protocol is provably secure, relying on the quantum property that information gain is only possible at the expense of disturbing the signal if the two states one is trying to distinguish are not orthogonal (see no-cloning theorem) and an authenticated public classical channel. It is usually explained as a method of securely communicating a private key from one party to another for use in one-time pad encryption.

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πŸ”— Ruin Value

πŸ”— Architecture

Ruin value (German: Ruinenwert) is the concept that a building be designed such that if it eventually collapsed, it would leave behind aesthetically pleasing ruins that would last far longer without any maintenance at all. The idea was pioneered by German architect Albert Speer while planning for the 1936 Summer Olympics and published as "The Theory of Ruin Value" (Die Ruinenwerttheorie), although he was not its original inventor. The intention did not stretch only to the eventual collapse of the buildings, but rather assumed such buildings were inherently better designed and more imposing during their period of use.

The idea was supported by Adolf Hitler, who planned for such ruins to be a symbol of the greatness of the Third Reich, just as Ancient Greek and Roman ruins were symbolic of those civilisations.

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πŸ”— Kearny Fallout Meter

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory

The Kearny fallout meter, or KFM, is an expedient radiation meter. It is designed such that someone with a normal mechanical ability would be able to construct it before or during a nuclear attack, using common household items.

The Kearny fallout meter was developed by Cresson Kearny from research performed at Oak Ridge National Laboratory and published in the civil defense manual Nuclear War Survival Skills (ISBNΒ 0-942487-01-X). The plans were originally released in Oak Ridge National Laboratory publication ORNL-5040, The KFM, A Homemade Yet Accurate and Dependable Fallout Meter and have been formatted in a newsprint-ready layout so that they may be quickly printed with accurate dimensions in local newspapers. It must be built from a correctly scaled copy of the plans; photocopies and printouts of digital copies may not be to scale.

πŸ”— Mass Noun

πŸ”— Linguistics

In linguistics, a mass noun, uncountable noun, non-count noun, uncount noun, or just uncountable, is a noun with the syntactic property that any quantity of it is treated as an undifferentiated unit, rather than as something with discrete elements. Non-count nouns are distinguished from count nouns.

Given that different languages have different grammatical features, the actual test for which nouns are mass nouns may vary between languages. In English, mass nouns are characterized by the impossibility of being directly modified by a numeral without specifying a unit of measurement and by the impossibility of being combined with an indefinite article (a or an). Thus, the mass noun "water" is quantified as "20 litres of water" while the count noun "chair" is quantified as "20 chairs". However, both mass and count nouns can be quantified in relative terms without unit specification (e.g., "so much water", "so many chairs").

Mass nouns have no concept of singular and plural, although in English they take singular verb forms. However, many mass nouns in English can be converted to count nouns, which can then be used in the plural to denote (for instance) more than one instance or variety of a certain sort of entity – for example, "Many cleaning agents today are technically not soaps [i.e. types of soap], but detergents," or "I drank about three beers [i.e. bottles or glasses of beer]".

Some nouns can be used indifferently as mass or count nouns, e.g., three cabbages or three heads of cabbage; three ropes or three lengths of rope. Some have different senses as mass and count nouns: paper is a mass noun as a material (three reams of paper, one sheet of paper), but a count noun as a unit of writing ("the students passed in their papers").

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πŸ”— A/UX: Apple Unix for Macintosh

πŸ”— Apple Inc. πŸ”— Software πŸ”— Software/Computing

A/UX is a Unix-based operating system from Apple Computer for Macintosh computers, integrated with System 7's graphical interface and application compatibility. It is Apple's first official Unix-based operating system, launched in 1988 and discontinued in 1995 with version 3.1.1. A/UX requires select 68k-based Macintosh models with an FPU and a paged memory management unit (PMMU), including the Macintosh II, SE/30, Quadra, and Centris series.

Described by InfoWorld as "an open systems solution with the Macintosh at its heart", A/UX is based on UNIX System V Release 2.2, with features from System V Releases 3 and 4 and BSD versions 4.2 and 4.3. It is POSIX- and System V Interface Definition (SVID)-compliant and includes TCP/IP networking since version 2. Having a Unix-compatible, POSIX-compliant operating system enabled Apple to bid for large contracts to supply computers to U.S. federal government institutes.

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