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🔗 Board and table games

Rithmomachy (or Rithmomachia, also Arithmomachia, Rythmomachy, Rhythmomachy, or sundry other variants; sometimes known as The Philosophers' Game) is a highly complex, early European mathematical board game. The earliest known description of it dates from the eleventh century. A literal translation of the name is "The Battle of the Numbers". The game is much like chess, except most methods of capture depend on the numbers inscribed on each piece.

It has been argued that between the twelfth and sixteenth centuries, "rithmomachia served as a practical exemplar for teaching the contemplative values of Boethian mathematical philosophy, which emphasized the natural harmony and perfection of number and proportion. The game, Moyer argues, was used both as a mnemonic drill for the study of Boethian number theory and, more importantly, as a vehicle for moral education, by reminding players of the mathematical harmony of creation."

🔗 Apple Inc./Macintosh 🔗 Apple Inc. 🔗 Computing 🔗 Computing/Software

OpenDoc is a multi-platform software componentry framework standard created by Apple for compound documents, intended as an alternative to Microsoft's Object Linking and Embedding (OLE). As part of the AIM alliance between Apple, IBM, and Motorola, OpenDoc is one of Apple's earliest experiments with open standards and collaborative development methods with other companies—effectively starting an industry consortium. Active development was discontinued in March 1997.

The core idea of OpenDoc is to create small, reusable components, responsible for a specific task, such as text editing, bitmap editing, or browsing an FTP server. OpenDoc provides a framework in which these components can run together, and a document format for storing the data created by each component. These documents can then be opened on other machines, where the OpenDoc frameworks substitute suitable components for each part, even if they are from different vendors. In this way users can "build up" their documents from parts. Since there is no main application and the only visible interface is the document itself, the system is known as document centered.

At its inception, it was envisioned that OpenDoc would allow smaller, third-party developers to enter the then-competitive office software market, able to build one good editor instead of having to provide a complete suite.

🔗 Computing

In computer programming, homoiconicity (from the Greek words homo- meaning "the same" and icon meaning "representation") is a property of some programming languages. A language is homoiconic if a program written in it can be manipulated as data using the language, and thus the program's internal representation can be inferred just by reading the program itself. For example, a Lisp program is written as a regular Lisp list, and can be manipulated by other Lisp code. In homoiconic languages, all code can be accessed and transformed as data, using the same representation. This property is often summarized by saying that the language treats "code as data".

In a homoiconic language, the primary representation of programs is also a data structure in a primitive type of the language itself. This makes metaprogramming easier than in a language without this property: reflection in the language (examining the program's entities at runtime) depends on a single, homogeneous structure, and it does not have to handle several different structures that would appear in a complex syntax.

As noted above, a commonly cited example is Lisp, which was created to allow for easy list manipulations and where the structure is given by S-expressions that take the form of nested lists. Lisp programs are written in the form of lists; the result is that the program can access its own functions and procedures while running, and programmatically alter itself on the fly. Homoiconic languages typically include full support of syntactic macros, allowing the programmer to express transformations of programs in a concise way. Examples are the programming languages Clojure (a contemporary dialect of Lisp), Rebol (also its successor Red), Refal, Prolog, and more recently Julia.

🔗 British Museum 🔗 Radio 🔗 BBC 🔗 Radio/UK Radio

A History of the World in 100 Objects was a joint project of BBC Radio 4 and the British Museum, comprising a 100-part radio series written and presented by British Museum director Neil MacGregor. In 15-minute presentations broadcast on weekdays on Radio 4, MacGregor used objects of ancient art, industry, technology and arms, all of which are in the British Museum's collections, as an introduction to parts of human history. The series, four years in planning, began on 18 January 2010 and was broadcast over 20 weeks. A book to accompany the series, A History of the World in 100 Objects by Neil MacGregor, was published by Allen Lane on 28 October 2010. The entire series is also available for download along with an audio version of the book for purchase. The British Museum won the 2011 Art Fund Prize for its role in hosting the project.

In 2016, a touring exhibition of several items depicted on the radio program, also titled A History of the World in 100 Objects, travelled to various destinations, including Abu Dhabi (Manarat Al Saadiyat), Taiwan (National Palace Museum in Taipei), Japan (Tokyo Metropolitan Art Museum in Tokyo, Kyushu National Museum in Daizafu, and Kobe City Museum in Kobe), Australia (Western Australian Museum in Perth and National Museum of Australia in Canberra), and China (National Museum of China in Beijing and Shanghai Museum in Shanghai).

🔗 Spaceflight 🔗 Physics

The flyby anomaly is a discrepancy between current scientific models and the actual increase in speed (i.e. increase in kinetic energy) observed during a planetary flyby (usually of Earth) by a spacecraft. In multiple cases, spacecraft have been observed to gain greater speed than scientists had predicted, but thus far no convincing explanation has been found. This anomaly has been observed as shifts in the S-band and X-band Doppler and ranging telemetry. The largest discrepancy noticed during a flyby has been 13 mm/s.

🔗 Medicine 🔗 Food and drink 🔗 Medicine/Toxicology 🔗 Pharmacology 🔗 Medicine/Society and Medicine

Some fruit juices and fruits can interact with numerous drugs, in many cases causing adverse effects. The effect was first discovered accidentally, when a test of drug interactions with alcohol used grapefruit juice to hide the taste of the ethanol.

The effect is most studied with grapefruit and grapefruit juice, but similar effects have been observed with certain other citrus fruits. One medical review advises patients to avoid all citrus juices until further research clarifies the risks. Effects have been observed with apple juice, but their clinical significance is not yet known.

One whole grapefruit, or a small glass (200 mL (6.8 US fl oz)) of grapefruit juice, can cause drug overdose toxicity. Fruit consumed three days before the medicine can still have an effect. The relative risks of different types of citrus fruit have not been systematically studied. Affected drugs typically have an auxiliary label saying “Do not take with grapefruit” on the container, and the interaction is elaborated upon in the package insert. People are also advised to ask their physician or pharmacist about drug interactions.

The effects are caused by furanocoumarins (and, to a lesser extent, flavonoids). These chemicals inhibit key drug metabolizing enzymes, such as cytochrome P450 3A4 (CYP3A4). CYP3A4 is a metabolizing enzyme for almost 50% of drugs, and is found in the liver and small intestinal epithelial cells. As a result, many drugs are affected. Inhibition of enzymes can have two different effects, depending on whether the drug is either

1. metabolized by the enzyme to an inactive metabolite, or
2. activated by the enzyme to an active metabolite.

In the first instance, inhibition of drug-metabolizing enzymes results in elevated concentrations of an active drug in the body, which may cause adverse effects. Conversely, if the medication is a prodrug, it needs to be metabolised to be converted to the active drug. Compromising its metabolism lowers concentrations of the active drug, reducing its therapeutic effect, and risking therapeutic failure.

Low drug concentrations can also be caused when the fruit suppresses drug absorption from the intestine.

🔗 Game theory

The pirate game is a simple mathematical game. It is a multi-player version of the ultimatum game.

🔗 Economics 🔗 Sociology

Commons-based peer production (CBPP) is a term coined by Harvard Law School professor Yochai Benkler. It describes a model of socio-economic production in which large numbers of people work cooperatively; usually over the Internet. Commons-based projects generally have less rigid hierarchical structures than those under more traditional business models. Often—but not always—commons-based projects are designed without a need for financial compensation for contributors. For example, sharing of STL (file format) design files for objects freely on the internet enables anyone with a 3-D printer to digitally replicate the object saving the prosumer significant money.

The term is often used interchangeably with the term social production.

🔗 Physics 🔗 Antarctica

The lowest natural temperature ever directly recorded at ground level on Earth is −89.2 °C (−128.6 °F; 184.0 K) at the Soviet Vostok Station in Antarctica on 21 July 1983 by ground measurements.

On 10 August 2010, satellite observations showed a surface temperature of −93.2 °C (−135.8 °F; 180.0 K) at 81.8°S 59.3°E / -81.8; 59.3, along a ridge between Dome Argus and Dome Fuji, at 3,900 m (12,800 ft) elevation. The result was reported at the 46th annual meeting of the American Geophysical Union in San Francisco in December 2013; it is a provisional figure, and may be subject to revision. The value is not listed as the record lowest temperature as it was measured by remote sensing from satellite and not by ground-based thermometers, unlike the 1983 record. The temperature announced reflects that of the ice surface, while the Vostok readings measured the air above the ice, and so the two are not directly comparable. More recent work shows many locations in the high Antarctic where surface temperatures drop to approximately −98 °C (−144 °F; 175 K). Due to the very strong temperature gradient near the surface, these imply near-surface air temperature minima of approximately −94 °C (−137 °F; 179 K).