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🔗 Computing 🔗 Computing/Computer hardware

M.2, formerly known as the Next Generation Form Factor (NGFF), is a specification for internally mounted computer expansion cards and associated connectors. M.2 replaces the mSATA standard, which uses the PCI Express Mini Card physical card layout and connectors. Employing a more flexible physical specification, the M.2 allows different module widths and lengths, and, paired with the availability of more advanced interfacing features, makes the M.2 more suitable than mSATA in general for solid-state storage applications, and particularly in smaller devices such as ultrabooks and tablets.

Computer bus interfaces provided through the M.2 connector are PCI Express 3.0 (up to four lanes), Serial ATA 3.0, and USB 3.0 (a single logical port for each of the latter two). It is up to the manufacturer of the M.2 host or module to select which interfaces are to be supported, depending on the desired level of host support and device type. The M.2 connector keying notches denote various purposes and capabilities of both M.2 hosts and devices. The unique key notches of M.2 modules also prevent them from being inserted into incompatible host connectors.

The M.2 specification supports NVM Express (NVMe) as the logical device interface for M.2 PCI Express SSDs, in addition to supporting legacy Advanced Host Controller Interface (AHCI) at the logical interface level. While the support for AHCI ensures software-level backward compatibility with legacy SATA devices and legacy operating systems, NVM Express is designed to fully utilize the capability of high-speed PCI Express storage devices to perform many I/O operations in parallel.

🔗 Economics

Veblen goods are types of luxury goods for which the quantity demanded increases as the price increases, an apparent contradiction of the law of demand, resulting in an upward-sloping demand curve. A higher price may make a product desirable as a status symbol in the practices of conspicuous consumption and conspicuous leisure. A product may be a Veblen good because it is a positional good, something few others can own.

Veblen goods are named after American economist Thorstein Veblen, who first identified conspicuous consumption as a mode of status-seeking in The Theory of the Leisure Class (1899). A corollary of the Veblen effect is that lowering the price decreases the quantity demanded.

🔗 Philosophy 🔗 Philosophy/Social and political philosophy 🔗 Football

Three-sided football (often referred to as 3SF) is a variation of association football played with three teams instead of the usual two. It was devised by the Danish Situationist Asger Jorn to explain his notion of triolectics, his refinement on the Marxian concept of dialectics, as well as to disrupt one's everyday idea of football. Played on a hexagonal pitch [1], the game can be adapted for similarity to soccer as well as other versions of football.

Unlike conventional football, where the winner is determined by the highest scoring of the two teams, in three-sided football the winning team is that which concedes the fewest goals.

In decision theory, the sure-thing principle states that a decision maker who would take a certain action if he knew that event E has occurred, and also if he knew that the negation of E has occurred, should also take that same action if he knows nothing about E.

The principle was coined by L.J. Savage:

A businessman contemplates buying a certain piece of property. He considers the outcome of the next presidential election relevant. So, to clarify the matter to himself, he asks whether he would buy if he knew that the Democratic candidate were going to win, and decides that he would. Similarly, he considers whether he would buy if he knew that the Republican candidate were going to win, and again finds that he would. Seeing that he would buy in either event, he decides that he should buy, even though he does not know which event obtains, or will obtain, as we would ordinarily say. It is all too seldom that a decision can be arrived at on the basis of this principle, but except possibly for the assumption of simple ordering, I know of no other extralogical principle governing decisions that finds such ready acceptance.

He formulated the principle as a dominance principle, but it can also be framed probabilistically. Richard Jeffrey and later Judea Pearl showed that Savage's principle is only valid when the probability of the event considered (e.g., the winner of the election) is unaffected by the action (buying the property). Under such conditions, the sure-thing principle is a theorem in the do-calculus (see Bayes networks). Blyth constructed a counterexample to the sure-thing principle using sequential sampling in the context of Simpson's paradox, but this example violates the required action-independence provision.

The principle is closely related to independence of irrelevant alternatives, and equivalent under the axiom of truth (everything the agent knows is true). It is similarly targeted by the Ellsberg and Allais paradoxes, in which actual people's choices seem to violate this principle.

The Mississippi River Basin Model Waterways Experiment Station, located near Clinton, Mississippi, was a large-scale hydraulic model of the entire Mississippi River basin, covering an area of 200 acres. The model was built from 1943 to 1966 and in operation from 1949 until 1973. By comparison, the better known San Francisco Bay Model covers 1.5 acres and the Chesapeake Bay Model covers 8 acres. The model is now derelict, but open to the public within Buddy Butts Park, Jackson.

🔗 Physics

The one-electron universe postulate, proposed by John Wheeler in a telephone call to Richard Feynman in the spring of 1940, is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time. According to Feynman:

🔗 Technology 🔗 Physics 🔗 Physics/Fluid Dynamics

Fluidics, or fluidic logic, is the use of a fluid to perform analog or digital operations similar to those performed with electronics.

The physical basis of fluidics is pneumatics and hydraulics, based on the theoretical foundation of fluid dynamics. The term fluidics is normally used when devices have no moving parts, so ordinary hydraulic components such as hydraulic cylinders and spool valves are not considered or referred to as fluidic devices.

A jet of fluid can be deflected by a weaker jet striking it at the side. This provides nonlinear amplification, similar to the transistor used in electronic digital logic. It is used mostly in environments where electronic digital logic would be unreliable, as in systems exposed to high levels of electromagnetic interference or ionizing radiation.

Nanotechnology considers fluidics as one of its instruments. In this domain, effects such as fluid-solid and fluid-fluid interface forces are often highly significant. Fluidics have also been used for military applications.

🔗 Religion 🔗 Philosophy 🔗 Classical Greece and Rome 🔗 Iraq 🔗 Christianity

Mandaeism or Mandaeanism (Arabic: مَنْدَائِيَّة‎, Mandāʾīyah), also known as Sabaeanism (Arabic: صَابِئِيَّة‎, Ṣābiʾīyah), is a monotheistic and gnostic religion with a strongly dualistic cosmology. Its adherents, the Mandaeans, revere Adam, Abel, Seth, Enos, Noah, Shem, Aram, and especially John the Baptist. The Mandaeans have been counted among the Semites and speak a dialect of Eastern Aramaic known as Mandaic. The name 'Mandaean' is said to come from the Aramaic manda meaning "knowledge", as does Greek gnosis. Within the Middle East, but outside of their community, the Mandaeans are more commonly known as the Ṣubba (singular: Ṣubbī) or Sabians. The term Ṣubba is derived from the Aramaic root related to baptism, the neo-Mandaic is Ṣabi. In Islam, the "Sabians" (Arabic: الصَّابِئُون‎, aṣ-Ṣābiʾūn) are described several times in the Quran as People of the Book, alongside Jews and Christians. Occasionally, Mandaeans are called "Christians of Saint John".

According to most scholars, Mandaeaism originated sometime in the first three centuries AD, in either southwestern Mesopotamia or the Syro-Palestinian area. However, some scholars take the view that Mandaeanism is older and dates from pre-Christian times.

The religion has been practised primarily around the lower Karun, Euphrates and Tigris and the rivers that surround the Shatt-al-Arab waterway, part of southern Iraq and Khuzestan Province in Iran. There are thought to be between 60,000 and 70,000 Mandaeans worldwide. Until the Iraq War, almost all of them lived in Iraq. Many Mandaean Iraqis have since fled their country because of the turmoil created by the 2003 invasion of Iraq and subsequent occupation by U.S. armed forces, and the related rise in sectarian violence by Muslim extremists. By 2007, the population of Mandaeans in Iraq had fallen to approximately 5,000.

The Mandaeans have remained separate and intensely private. Reports of them and of their religion have come primarily from outsiders: particularly from Julius Heinrich Petermann, an Orientalist as well as from Nicolas Siouffi, a Syrian Christian who was the French vice-consul in Mosul in 1887, and British cultural anthropologist Lady E. S. Drower. There is an early if highly prejudiced account by the French traveller Jean-Baptiste Tavernier from the 1650s.

🔗 Telecommunications

Signaling System No. 7 (SS7) is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN). The protocol also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services.

In North America SS7 is often referred to as Common Channel Signaling System 7 (CCSS7). In the United Kingdom, it is called C7 (CCITT number 7), number 7 and Common Channel Interoffice Signaling 7 (CCIS7). In Germany, it is often called Zentraler Zeichengabekanal Nummer 7 (ZZK-7).

The SS7 protocol is defined for international use by the Q.700-series recommendations of 1988 by the ITU-T. Of the many national variants of the SS7 protocols, most are based on variants standardized by the American National Standards Institute (ANSI) and the European Telecommunications Standards Institute (ETSI). National variants with striking characteristics are the Chinese and Japanese Telecommunication Technology Committee (TTC) national variants.

The Internet Engineering Task Force (IETF) has defined the SIGTRAN protocol suite that implements levels 2, 3, and 4 protocols compatible with SS7. Sometimes also called Pseudo SS7, it is layered on the Stream Control Transmission Protocol (SCTP) transport mechanism for use on Internet Protocol networks, such as the Internet.

🔗 Chess 🔗 Boxing

Chess boxing, or chessboxing, is a hybrid that combines two traditional pastimes: chess, a cerebral board game, and boxing, a physical sport. The competitors fight in alternating rounds of chess and boxing. Chessboxing was invented by French comic book artist Enki Bilal and adapted by Dutch performance artist Iepe Rubingh as an art performance and has subsequently grown into a competitive sport. Chessboxing is particularly popular in Germany, the United Kingdom, India, and Russia.