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🔗 Linguistics 🔗 Professional wrestling

In professional wrestling, kayfabe (also called work or worked) is the portrayal of staged events within the industry as "real" or "true", specifically the portrayal of competition, rivalries, and relationships between participants as being genuine and not of a staged or predetermined nature of any kind. The term kayfabe has evolved to also become a code word of sorts for maintaining this "reality" within the direct or indirect presence of the general public.

Kayfabe is often seen as the suspension of disbelief that is used to create the non-wrestling aspects of promotions, such as feuds, angles, and gimmicks in a manner similar to other forms of fictional entertainment. In relative terms, a wrestler breaking kayfabe during a show would be likened to an actor breaking character on-camera. Also, since wrestling is performed in front of a live audience, whose interaction with the show is crucial to its success, kayfabe can be compared to the fourth wall in acting, since hardly any conventional fourth wall exists to begin with. In general, everything in a professional wrestling show is to some extent scripted, or "kayfabe", even though at times it is portrayed as real-life.

Kayfabe was fiercely maintained for decades, but with the advent of the Internet wrestling community, and the sports entertainment movement, the pro wrestling industry has become less concerned with protecting so-called backstage secrets and typically maintains kayfabe only during the shows. Kayfabe is, however, occasionally broken during shows, usually when dealing with genuine injuries during a match or paying tribute to wrestlers.

🔗 California 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/World War II 🔗 Paranormal 🔗 California/Southern California

The Battle of Los Angeles, also known as the Great Los Angeles Air Raid, is the name given by contemporary sources to a rumored attack on the mainland United States by Imperial Japan and the subsequent anti-aircraft artillery barrage which took place from late 24 February to early 25 February 1942, over Los Angeles, California. The incident occurred less than three months after the U.S. entered World War II in response to the Imperial Japanese Navy's surprise attack on Pearl Harbor, and one day after the bombardment of Ellwood near Santa Barbara on 23 February. Initially, the target of the aerial barrage was thought to be an attacking force from Japan, but speaking at a press conference shortly afterward, Secretary of the Navy Frank Knox called the purported attack a "false alarm". Newspapers of the time published a number of reports and speculations of a cover-up.

When documenting the incident in 1949, the United States Coast Artillery Association identified a meteorological balloon sent aloft at 1:00 am as having "started all the shooting" and concluded that "once the firing started, imagination created all kinds of targets in the sky and everyone joined in". In 1983, the U.S. Office of Air Force History attributed the event to a case of "war nerves" triggered by a lost weather balloon and exacerbated by stray flares and shell bursts from adjoining batteries.

🔗 Linguistics 🔗 Czech Republic 🔗 Slovakia 🔗 Linguistics/Phonetics

Strč prst skrz krk (pronounced [str̩tʃ pr̩st skr̩s kr̩k] (listen)) is a Czech and Slovak tongue-twister meaning "stick a finger through the throat".

The sentence is well known for being a semantically and syntactically valid clause without a single vowel, the nucleus of each syllable being a syllabic r, a common feature among many Slavic languages. It is often used as an example of such a phrase when learning Czech or Slovak as a foreign language.

In fact, both Czech and Slovak have two syllabic liquid consonants, the other being syllabic l. (There is also the syllabic bilabial nasal m in sedm in Czech.) As a result, there are plenty of words without vowels. Examples of long words of this type are scvrnkls, čtvrthrst, and čtvrtsmršť, the latter two being artificial occasionalisms.

There are other examples of vowelless sentences in Czech and Slovak, such as prd krt skrz drn, zprv zhlt hrst zrn, meaning "a mole farted through grass, having swallowed a handful of grains".

The longest Czech vowelless sentence (with 25 words and 82 consonants) as of 2013 is Škrt plch z mlh Brd pln skvrn z mrv prv hrd scvrnkl z brzd skrz trs chrp v krs vrb mls mrch srn čtvrthrst zrn. The meaning of the sentence is: Stingy dormouse from Brdy mountains fogs full of manure spots firstly proudly shrank a quarter of handful seeds, a delicacy for mean does, from brakes through bunch of Centaurea flowers into scrub of willows. IPA pronunciation of this sentence is [ʃkr̩t pl̩x zml̩x br̩t pl̩n skvr̩n zmr̩f pr̩f ɦr̩t st͡svrn̩kl̩ zbr̩st skr̩s tr̩s xr̩p fkr̩s vr̩p ml̩s mr̩x sr̩n t͡ʃtvrdɦr̩st zr̩n].

🔗 Mathematics

The Banach–Tarski paradox is a theorem in set-theoretic geometry, which states the following: Given a solid ball in 3‑dimensional space, there exists a decomposition of the ball into a finite number of disjoint subsets, which can then be put back together in a different way to yield two identical copies of the original ball. Indeed, the reassembly process involves only moving the pieces around and rotating them without changing their shape. However, the pieces themselves are not "solids" in the usual sense, but infinite scatterings of points. The reconstruction can work with as few as five pieces.

A stronger form of the theorem implies that given any two "reasonable" solid objects (such as a small ball and a huge ball), the cut pieces of either one can be reassembled into the other. This is often stated informally as "a pea can be chopped up and reassembled into the Sun" and called the "pea and the Sun paradox".

The reason the Banach–Tarski theorem is called a paradox is that it contradicts basic geometric intuition. "Doubling the ball" by dividing it into parts and moving them around by rotations and translations, without any stretching, bending, or adding new points, seems to be impossible, since all these operations ought, intuitively speaking, to preserve the volume. The intuition that such operations preserve volumes is not mathematically absurd and it is even included in the formal definition of volumes. However, this is not applicable here because in this case it is impossible to define the volumes of the considered subsets. Reassembling them reproduces a volume, which happens to be different from the volume at the start.

Unlike most theorems in geometry, the proof of this result depends in a critical way on the choice of axioms for set theory. It can be proven using the axiom of choice, which allows for the construction of non-measurable sets, i.e., collections of points that do not have a volume in the ordinary sense, and whose construction requires an uncountable number of choices.

It was shown in 2005 that the pieces in the decomposition can be chosen in such a way that they can be moved continuously into place without running into one another.

🔗 United States 🔗 Computing 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Iran 🔗 Computing/Software 🔗 Computing/Computer Security 🔗 Military history/Middle Eastern military history

Stuxnet is a malicious computer worm, first uncovered in 2010, thought to have been in development since at least 2005. Stuxnet targets supervisory control and data acquisition (SCADA) systems and is believed to be responsible for causing substantial damage to the nuclear program of Iran. Although neither country has openly admitted responsibility, the worm is widely understood to be a cyberweapon built jointly by the United States and Israel.

Stuxnet specifically targets programmable logic controllers (PLCs), which allow the automation of electromechanical processes such as those used to control machinery and industrial processes including gas centrifuges for separating nuclear material. Exploiting four zero-day flaws, Stuxnet functions by targeting machines using the Microsoft Windows operating system and networks, then seeking out Siemens Step7 software. Stuxnet reportedly compromised Iranian PLCs, collecting information on industrial systems and causing the fast-spinning centrifuges to tear themselves apart. Stuxnet's design and architecture are not domain-specific and it could be tailored as a platform for attacking modern supervisory control and data acquisition (SCADA) and PLC systems (e.g., in factory assembly lines or power plants), most of which are in Europe, Japan, and the US. Stuxnet reportedly ruined almost one-fifth of Iran's nuclear centrifuges. Targeting industrial control systems, the worm infected over 200,000 computers and caused 1,000 machines to physically degrade.

Stuxnet has three modules: a worm that executes all routines related to the main payload of the attack; a link file that automatically executes the propagated copies of the worm; and a rootkit component responsible for hiding all malicious files and processes, to prevent detection of Stuxnet. It is typically introduced to the target environment via an infected USB flash drive, thus crossing any air gap. The worm then propagates across the network, scanning for Siemens Step7 software on computers controlling a PLC. In the absence of either criterion, Stuxnet becomes dormant inside the computer. If both the conditions are fulfilled, Stuxnet introduces the infected rootkit onto the PLC and Step7 software, modifying the code and giving unexpected commands to the PLC while returning a loop of normal operation system values back to the users.

In 2015, Kaspersky Lab noted that the Equation Group had used two of the same zero-day attacks prior to their use in Stuxnet and commented that "the similar type of usage of both exploits together in different computer worms, at around the same time, indicates that the Equation Group and the Stuxnet developers are either the same or working closely together".

🔗 Plants 🔗 Forestry 🔗 Ecology

Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate disrupted biodiverse steady-state ecosystems as part of ecological succession. A number of kinds of events can create good conditions for pioneers, including disruption by natural disasters, such as wildfire, flood, mudslide, lava flow or a climate-related extinction event or by anthropogenic habitat destruction, such as through land clearance for agriculture or construction or industrial damage. Pioneer species play an important role in creating soil in primary succession, and stabilizing soil and nutrients in secondary succession.

For humans, because pioneer species quickly occupy disrupted spaces they are sometimes treated as weeds or nuisance wildlife, such as the common dandelion or stinging nettle. Even though humans have mixed relationships with these plants, these species tend to help improve the ecosystem because they can break up compacted soils and accumulate nutrients that help with a transition back to a more mature ecosystem. In human managed ecological restoration or agroforestry, trees and herbaceous pioneers can be used to restore soil qualities and provide shelter for slower growing or more demanding plants. Some systems use introduced species to restore the ecosystem, or for environmental remediation. The durability of pioneer species can also make them potential invasive species.

🔗 Biography 🔗 China 🔗 Business 🔗 Women

Zhou Qunfei (Chinese: 周群飞; born 1970) is a Chinese entrepreneur who founded the major touchscreen maker Lens Technology. After the public listing of her company on the Shenzhen ChiNext market in March 2015, her net worth reached US$10 billion, making her the richest woman in China. In 2018, she was named the world's richest self-made woman, with a net worth of $9.8 billion.

🔗 Computing 🔗 Computing/Networking

The Network Control Program (NCP) provided the middle layers of the protocol stack running on host computers of the ARPANET, the predecessor to the modern Internet.

NCP preceded the Transmission Control Protocol (TCP) as a transport layer protocol used during the early ARPANET. NCP was a simplex protocol that utilized two port addresses, establishing two connections, for two-way communications. An odd and an even port were reserved for each application layer application or protocol. The standardization of TCP and UDP reduced the need for the use of two simplex ports for each application down to one duplex port.

🔗 Chemicals

Aluminium oxynitride (marketed under the name ALON by Surmet Corporation) is a transparent ceramic composed of aluminium, oxygen and nitrogen. ALON is optically transparent (≥ 80%) in the near-ultraviolet, visible, and midwave-infrared regions of the electromagnetic spectrum. It is four times as hard as fused silica glass, 85% as hard as sapphire, and nearly 115% as hard as magnesium aluminate spinel. Since it has a cubic spinel structure, it can be fabricated to transparent windows, plates, domes, rods, tubes, and other forms using conventional ceramic powder processing techniques.

ALON is the hardest polycrystalline transparent ceramic available commercially. Because of its relatively low weight, distinctive optical and mechanical properties, and resistance to oxidation or radiation, it shows promise for applications such as bulletproof, blast-resistant, and optoelectronic windows. ALON-based armor has been shown to stop multiple armor-piercing projectiles of up to .50 BMG.

ALON is commercially available in sizes as large as 18-by-35-inch (460 mm × 890 mm; 46 cm × 89 cm) monolithic windows.

🔗 Economics 🔗 Education 🔗 Game theory 🔗 Games

A simulation game is "a game that contains a mixture of skill, chance, and strategy to simulate an aspect of reality, such as a stock exchange". Similarly, Finnish author Virpi Ruohomäki states that "a simulation game combines the features of a game (competition, cooperation, rules, participants, roles) with those of a simulation (incorporation of critical features of reality). A game is a simulation game if its rules refer to an empirical model of reality". A properly built simulation game used to teach or learn economics would closely follow the assumptions and rules of the theoretical models within this discipline.