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🔗 Claude Émile Jean-Baptiste Litre

🔗 Fictional characters 🔗 Chemistry 🔗 Measurement

Claude Émile Jean-Baptiste Litre is a fictional character created in 1978 by Kenneth Woolner of the University of Waterloo to justify the use of a capital L to denote litres.

The International System of Units usually only permits the use of a capital letter when a unit is named after a person. The lower-case character l might be difficult to distinguish from the upper-case character I or the digit 1 in certain fonts and styles, and therefore both the lower-case (l) and the upper-case (L) are allowed as the symbol for litre. The United States National Institute of Standards and Technology now recommends the use of the uppercase letter L, a practice that is also widely followed in Canada and Australia.

Woolner perpetrated the April Fools' Day hoax in the April 1978 issue of "CHEM 13 News", a newsletter concerned with chemistry for school teachers. According to the hoax, Claude Litre was born on 12 February 1716, the son of a manufacturer of wine bottles. During Litre's extremely distinguished fictional scientific career, he purportedly proposed a unit of volume measurement that was incorporated into the International System of Units after his death in 1778.

The hoax was mistakenly printed as fact in the IUPAC journal Chemistry International and subsequently retracted.

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🔗 20 years ago Far Cry was released

🔗 Video games

Far Cry is a 2004 first-person shooter game developed by Crytek and published by Ubisoft. It is the first installment in the Far Cry franchise. Set on a mysterious tropical archipelago, the game follows Jack Carver, a former American special operations forces operative, as he searches for journalist Valerie Constantine, who accompanied him to the islands but went missing after their boat was destroyed by mercenaries. As Jack explores the islands, he begins to discover the horrific genetic experiments being conducted on the local wildlife and must confront the mad scientist behind them.

The game was the first to use Crytek's CryEngine, and was designed as an open-ended first-person shooter, though it lacks most of the freedom its successors would offer to the player. While players can freely explore the game's world like in later Far Cry titles, they are most often discouraged from doing so due to the linear structure of missions and the lack of side content. Despite this, the gameplay formula established in Far Cry—placing the player in a foreign environment occupied by enemy forces where they must use various weapons and tools, as well as their surroundings to overcome any threat—would prove essential in defining the series' identity going forward.

Far Cry was released for Microsoft Windows in March 2004 to generally positive reviews, being praised for its visuals, gameplay mechanics, and the level of freedom given to players. The game was also a commercial success, selling over 730,000 units within four months of release and over 2.5 million units in its lifetime. The success of Far Cry led to a series of standalone sequels developed by Ubisoft, starting with Far Cry 2 in 2008. A remake of the game with a different storyline and new mechanics, Far Cry Instincts, was released for the Xbox in 2005, and for the Xbox 360 in 2006 as part of the Far Cry Instincts: Predator compilation. A loose film adaptation was released in 2008. The original version of Far Cry, updated with HD graphics, was re-released under the title Far Cry Classic for the PlayStation 3 and Xbox 360 in 2014.

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🔗 Organopónicos

🔗 Cuba

Organopónicos or organoponics is a system of urban agriculture using organic gardens. It originated in Cuba and is still mostly focused there. It often consists of low-level concrete walls filled with organic matter and soil, with lines of drip irrigation laid on the surface of the growing media. Organopónicos is a labour-intensive form of local agriculture.

Organopónico farmers employ a wide variety of agroecological techniques including integrated pest management, polyculture, and crop rotation. Most organic materials are also produced within the gardens through composting. This allows production to take place with few petroleum-based inputs.

Organopónicos first arose as a community response to lack of food security during the Special Period after the collapse of the Soviet Union. It is publicly functioning in terms of ownership, access, and management, but heavily subsidized and supported by the Cuban government.

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🔗 Photophone

The photophone is a telecommunications device that allows transmission of speech on a beam of light. It was invented jointly by Alexander Graham Bell and his assistant Charles Sumner Tainter on February 19, 1880, at Bell's laboratory at 1325 L Street in Washington, D.C. Both were later to become full associates in the Volta Laboratory Association, created and financed by Bell.

On June 3, 1880, Bell's assistant transmitted a wireless voice telephone message from the roof of the Franklin School to the window of Bell's laboratory, some 213 meters (about 700 ft.) away.

Bell believed the photophone was his most important invention. Of the 18 patents granted in Bell's name alone, and the 12 he shared with his collaborators, four were for the photophone, which Bell referred to as his "greatest achievement", telling a reporter shortly before his death that the photophone was "the greatest invention [I have] ever made, greater than the telephone".

The photophone was a precursor to the fiber-optic communication systems that achieved worldwide popular usage starting in the 1980s. The master patent for the photophone (U.S. Patent 235,199 Apparatus for Signalling and Communicating, called Photophone) was issued in December 1880, many decades before its principles came to have practical applications.

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🔗 Pizza Effect

🔗 Religion 🔗 Sociology

In religious studies and sociology, the pizza effect is the phenomenon of elements of a nation or people's culture being transformed or at least more fully embraced elsewhere, then re-imported back to their culture of origin, or the way in which a community's self-understanding is influenced by (or imposed by, or imported from) foreign sources. It is named after the idea that modern pizza toppings were developed among Italian immigrants in the United States (rather than in native Italy, where in its simpler form it was originally looked down upon), and was later exported back to Italy to be interpreted as a delicacy in Italian cuisine.

Related phrases include "hermeneutical feedback loop", "re-enculturation", and "self-orientalization". The term "pizza effect" was coined by the Austrian-born Hindu monk and professor of Anthropology at Syracuse University, Agehananda Bharati in 1970.

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🔗 Mental poker

Mental poker is the common name for a set of cryptographic problems that concerns playing a fair game over distance without the need for a trusted third party. The term is also applied to the theories surrounding these problems and their possible solutions. The name comes from the card game poker which is one of the games to which this kind of problem applies. Similar problems described as two party games are Blum's flipping a coin over a distance, Yao's Millionaires' Problem, and Rabin's oblivious transfer.

The problem can be described thus: "How can one allow only authorized actors to have access to certain information while not using a trusted arbiter?" (Eliminating the trusted third-party avoids the problem of trying to determine whether the third party can be trusted or not, and may also reduce the resources required.)

In poker, this could translate to: "How can we make sure no player is stacking the deck or peeking at other players' cards when we are shuffling the deck ourselves?". In a physical card game, this would be relatively simple if the players were sitting face to face and observing each other, at least if the possibility of conventional cheating can be ruled out. However, if the players are not sitting at the same location but instead are at widely separate locations and pass the entire deck between them (using the postal mail, for instance), this suddenly becomes very difficult. And for electronic card games, such as online poker, where the mechanics of the game are hidden from the user, this is impossible unless the method used is such that it cannot allow any party to cheat by manipulating or inappropriately observing the electronic "deck".

Several protocols for doing this have been suggested, the first by Adi Shamir, Ron Rivest and Len Adleman (the creators of the RSA-encryption protocol). This protocol was the first example of two parties conducting secure computation rather than secure message transmission, employing cryptography; later on due to leaking partial information in the original protocol, this led to the definition of semantic security by Shafi Goldwasser and Silvio Micali. The concept of multi-player mental poker was introduced in Moti Yung's 1984 book Cryptoprotocols. The area has later evolved into what is known as secure multi-party computation protocols (for two parties, and multi parties as well).

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🔗 How to Lie with Statistics

🔗 Statistics 🔗 Books 🔗 Project-independent assessment

How to Lie with Statistics is a book written by Darrell Huff in 1954, presenting an introduction to statistics for the general reader. Not a statistician, Huff was a journalist who wrote many how-to articles as a freelancer.

The book is a brief, breezy illustrated volume outlining the misuse of statistics and errors in the interpretation of statistics, and how errors create incorrect conclusions.

In the 1960s and 1970s, it became a standard textbook introduction to the subject of statistics for many college students. It has become one of the best-selling statistics books in history, with over one and a half million copies sold in the English-language edition. It has also been widely translated.

Themes of the book include "Correlation does not imply causation" and "Using random sampling." It also shows how statistical graphs can be used to distort reality. For example, by truncating the bottom of a line or bar chart so that differences seem larger than they are. Or, by representing one-dimensional quantities on a pictogram by two- or three-dimensional objects to compare their sizes so that the reader forgets that the images do not scale the same way the quantities do.

The original edition contained illustrations by artist Irving Geis. In a UK edition, Geis' illustrations were replaced by cartoons by Mel Calman.

🔗 Zooming User Interface (ZUI)

🔗 Computer science

In computing, a zooming user interface or zoomable user interface (ZUI, pronounced zoo-ee) is a type of graphical user interface (GUI) where users can change the scale of the viewed area in order to see more detail or less, and browse through different documents. Information elements appear directly on an infinite virtual desktop (usually created using vector graphics), instead of in windows. Users can pan across the virtual surface in two dimensions and zoom into objects of interest. For example, as you zoom into a text object it may be represented as a small dot, then a thumbnail of a page of text, then a full-sized page and finally a magnified view of the page.

ZUIs use zooming as the main metaphor for browsing through hyperlinked or multivariate information. Objects present inside a zoomed page can in turn be zoomed themselves to reveal further detail, allowing for recursive nesting and an arbitrary level of zoom.

When the level of detail present in the resized object is changed to fit the relevant information into the current size, instead of being a proportional view of the whole object, it's called semantic zooming.

Some consider the ZUI paradigm as a flexible and realistic successor to the traditional windowing GUI, being a Post-WIMP interface.

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🔗 Penrose Tiling

🔗 Mathematics

A Penrose tiling is an example of an aperiodic tiling. Here, a tiling is a covering of the plane by non-overlapping polygons or other shapes, and aperiodic means that shifting any tiling with these shapes by any finite distance, without rotation, cannot produce the same tiling. However, despite their lack of translational symmetry, Penrose tilings may have both reflection symmetry and fivefold rotational symmetry. Penrose tilings are named after mathematician and physicist Roger Penrose, who investigated them in the 1970s.

There are several different variations of Penrose tilings with different tile shapes. The original form of Penrose tiling used tiles of four different shapes, but this was later reduced to only two shapes: either two different rhombi, or two different quadrilaterals called kites and darts. The Penrose tilings are obtained by constraining the ways in which these shapes are allowed to fit together. This may be done in several different ways, including matching rules, substitution tiling or finite subdivision rules, cut and project schemes, and coverings. Even constrained in this manner, each variation yields infinitely many different Penrose tilings.

Penrose tilings are self-similar: they may be converted to equivalent Penrose tilings with different sizes of tiles, using processes called inflation and deflation. The pattern represented by every finite patch of tiles in a Penrose tiling occurs infinitely many times throughout the tiling. They are quasicrystals: implemented as a physical structure a Penrose tiling will produce diffraction patterns with Bragg peaks and five-fold symmetry, revealing the repeated patterns and fixed orientations of its tiles. The study of these tilings has been important in the understanding of physical materials that also form quasicrystals. Penrose tilings have also been applied in architecture and decoration, as in the floor tiling shown.

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🔗 Digital Mobile Radio

🔗 Telecommunications

Digital mobile radio (DMR) is a limited open digital mobile radio standard defined in the European Telecommunications Standards Institute (ETSI) Standard TS 102 361 parts 1–4 and used in commercial products around the world. DMR, along with P25 phase II and NXDN are the main competitor technologies in achieving 6.25 kHz equivalent bandwidth using the proprietary AMBE+2 vocoder. DMR and P25 II both use two-slot TDMA in a 12.5 kHz channel, while NXDN uses discrete 6.25 kHz channels using frequency division and TETRA uses a four-slot TDMA in a 25 kHz channel.

DMR was designed with three tiers. DMR tiers I and II (conventional) were first published in 2005, and DMR III (Trunked version) was published in 2012, with manufacturers producing products within a few years of each publication.

The primary goal of the standard is to specify a digital system with low complexity, low cost and interoperability across brands, so radio communications purchasers are not locked into a proprietary solution. In practice, given the current limited scope of the DMR standard, many vendors have introduced proprietary features that make their product offerings non-interoperable with other brands.

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