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🔗 Computing 🔗 Software 🔗 Software/Computing

In x86 computing, unreal mode, also big real mode, huge real mode, flat real mode, or voodoo mode is a variant of real mode, in which one or more segment descriptors has been loaded with non-standard values, like 32-bit limits allowing access to the entire memory. Contrary to its name, it is not a separate addressing mode that the x86 processors can operate in. It is used in the 80286 and later x86 processors.

🔗 Medicine 🔗 Neuroscience

Pain in babies, and whether babies feel pain, has been a large subject of debate within the medical profession for centuries. Prior to the late nineteenth century it was generally considered that babies hurt more easily than adults. It was only in the last quarter of the 20th century that scientific techniques finally established babies definitely do experience pain – probably more than adults – and developed reliable means of assessing and of treating it. As recently as 1999, it was commonly stated that babies could not feel pain until they were a year old, but today it is believed newborns and likely even fetuses beyond a certain age can experience pain.

🔗 Biology 🔗 Genetics 🔗 Computational Biology 🔗 Evolutionary biology 🔗 Human Genetic History

The last universal common ancestor (LUCA), also called the last universal ancestor (LUA), or concestor, is the most recent population of organisms from which all organisms now living on Earth have a common descent, the most recent common ancestor of all current life on Earth. (A related concept is that of progenote.) LUCA is not thought to be the first life on Earth but only one of many early organisms, all the others becoming extinct.

While there is no specific fossil evidence of LUCA, it can be studied by comparing the genomes of all modern organisms, its descendants. By this means, a 2016 study identified a set of 355 genes most likely to have been present in LUCA. (However, some of those genes could have developed later, then spread universally by horizontal gene transfer between archaea and bacteria.) The genes describe a complex life form with many co-adapted features, including transcription and translation mechanisms to convert information from DNA to RNA to proteins. The study concluded that the LUCA probably lived in the high-temperature water of deep sea vents near ocean-floor magma flows.

Studies from 2000 to 2018 have suggested an increasingly ancient time for LUCA. In 2000, estimations suggested LUCA existed 3.5 to 3.8 billion years ago in the Paleoarchean era, a few hundred million years after the earliest fossil evidence of life, for which there are several candidates ranging in age from 3.48 to 4.28 billion years ago. A 2018 study from the University of Bristol, applying a molecular clock model, places the LUCA shortly after 4.5 billion years ago, within the Hadean.

Charles Darwin first proposed the theory of universal common descent through an evolutionary process in his book On the Origin of Species in 1859: "Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed." Later biologists have separated the problem of the origin of life from that of the LUCA.

🔗 Technology 🔗 Physics 🔗 Color 🔗 Chemistry 🔗 Science

Vantablack is a material developed by Surrey NanoSystems in the United Kingdom and is one of the darkest substances known, absorbing up to 99.965% of visible light (at 663 nm if the light is perpendicular to the material).

The name is a compound of the acronym VANTA (vertically aligned nanotube arrays) and the color black.

🔗 Espionage 🔗 Books 🔗 Computer Security 🔗 Computer Security/Computing

The Cuckoo's Egg: Tracking a Spy Through the Maze of Computer Espionage is a 1989 book written by Clifford Stoll. It is his first-person account of the hunt for a computer hacker who broke into a computer at the Lawrence Berkeley National Laboratory (LBNL).

Stoll's use of the term extended the metaphor Cuckoo's egg from brood parasitism in birds to malware.

🔗 Computer science

TLA⁺ is a formal specification language developed by Leslie Lamport. It is used to design, model, document, and verify programs, especially concurrent systems and distributed systems. TLA⁺ has been described as exhaustively-testable pseudocode, and its use likened to drawing blueprints for software systems; TLA is an acronym for Temporal Logic of Actions.

For design and documentation, TLA⁺ fulfills the same purpose as informal technical specifications. However, TLA⁺ specifications are written in a formal language of logic and mathematics, and the precision of specifications written in this language is intended to uncover design flaws before system implementation is underway.

Since TLA⁺ specifications are written in a formal language, they are amenable to finite model checking. The model checker finds all possible system behaviours up to some number of execution steps, and examines them for violations of desired invariance properties such as safety and liveness. TLA⁺ specifications use basic set theory to define safety (bad things won't happen) and temporal logic to define liveness (good things eventually happen).

TLA⁺ is also used to write machine-checked proofs of correctness both for algorithms and mathematical theorems. The proofs are written in a declarative, hierarchical style independent of any single theorem prover backend. Both formal and informal structured mathematical proofs can be written in TLA⁺; the language is similar to LaTeX, and tools exist to translate TLA⁺ specifications to LaTeX documents.

TLA⁺ was introduced in 1999, following several decades of research into a verification method for concurrent systems. A toolchain has since developed, including an IDE and distributed model checker. The pseudocode-like language PlusCal was created in 2009; it transpiles to TLA⁺ and is useful for specifying sequential algorithms. TLA⁺² was announced in 2014, expanding language support for proof constructs. The current TLA⁺ reference is The TLA⁺ Hyperbook by Leslie Lamport.

🔗 Urban studies and planning

The Lewis–Mogridge position, named after David Lewis and Martin J. H. Mogridge, was formulated in 1990 and observes that as more roads are built, more traffic consequently fills these roads. Speed gains from some new roads can disappear within months, if not weeks. Sometimes, new roads help to reduce traffic jams, but in most cases, the congestion is only shifted to another junction.

The position reads traffic expands to meet the available road space (Mogridge, 1990). It is generally referred to as induced demand in the transport literature, and was posited as the "Iron Law of Congestion" by Anthony Downs. It is a special case of Jevons paradox (where the resource in question is traffic capacity), and relates to the Marchetti's constant (average commute times are similar in widely varying conditions).

Following the position, it is not generally concluded that new roads are never justified but that their development needs to consider the whole traffic system, which means understanding the movement of goods and people in detail as well as the motivation behind the movement.

The position is often used to understand problems caused by private transport such as congested roads in cities and on motorways. It can also be used to explain the success of schemes such as the London congestion charge.

The position, however, is not confined to private transport. Mogridge, a British transport researcher, concluded also that all road investment in a congested urban area will have the effect of reducing the average speed of the transport system as a whole: road and public transport. The relationship and overall equilibria are also known as the "Downs–Thomson paradox". However, according to Downs, the link between average speeds on public transport and private transport applies only "to regions in which the vast majority of peak-hour commuting is done on rapid transit systems with separate rights of way. Central London is an example, since in 2001 around 85 percent of all morning peak-period commuters into that area used public transit (including 77 percent on separate rights of way) and only 11 percent used private cars. When peak-hour travel equilibrium has been reached between the subway system and the major commuting roads, then the travel time required for any given trip is roughly equal on both modes."

🔗 United States/U.S. Government 🔗 United States 🔗 International relations 🔗 Germany 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Europe 🔗 Italy 🔗 Sociology 🔗 Organizations 🔗 Military history/German military history 🔗 Military history/French military history 🔗 Military history/Cold War 🔗 Cold War 🔗 Military history/Dutch military history 🔗 Rome 🔗 European history 🔗 Military history/Italian military history 🔗 Military history/European military history 🔗 Military history/British military history 🔗 Military history/Post-Cold War 🔗 NATO

Operation Gladio is the codename for clandestine "stay-behind" operations of armed resistance that were organized by the Western Union (WU), and subsequently by NATO and the CIA, in collaboration with several European intelligence agencies. The operation was designed for a potential Warsaw Pact invasion and conquest of Europe. Although Gladio specifically refers to the Italian branch of the NATO stay-behind organizations, "Operation Gladio" is used as an informal name for all of them. Stay-behind operations were prepared in many NATO member countries, and some neutral countries.

During the Cold War, some anti-communist armed groups engaged in the harassment of left-wing parties, torture, terrorist attacks, and massacres in countries such as Italy. The role of the CIA and other intelligence organisations in Gladio—the extent of its activities during the Cold War era and any responsibility for terrorist attacks perpetrated in Italy during the "Years of Lead" (late 1960s–early 1980s)—is the subject of debate.

In 1990, the European Parliament adopted a resolution alleging that military secret services in certain member states were involved in serious terrorism and crime, whether or not their superiors were aware. The resolution also urged investigations by the judiciaries of the countries in which those armies operated, so that their modus operandi and actual extension would be revealed. To date, only Italy, Switzerland and Belgium have had parliamentary inquiries into the matter.

The three inquiries reached differing conclusions as regarded different countries. Guido Salvini, a judge who worked in the Italian Massacres Commission, concluded that some right-wing terrorist organizations of the Years of Lead (La Fenice, National Vanguard and Ordine Nuovo) were the trench troops of a secret army, remotely controlled by exponents of the Italian state apparatus and linked to the CIA. Salvini said that the CIA encouraged them to commit atrocities. The Swiss inquiry found that British intelligence secretly cooperated with their army in an operation named P-26 and provided training in combat, communications, and sabotage. It also discovered that P-26 not only would organize resistance in case of a Soviet invasion, but would also become active should the left succeed in achieving a parliamentary majority. The Belgian inquiry could find no conclusive information on their army. No links between them and terrorist attacks were found, and the inquiry noted that the Belgian secret services refused to provide the identity of agents, which could have eliminated all doubts. A 2000 Italian parliamentary report from the left wing coalition Gruppo Democratici di Sinistra l'Ulivo reported that terrorist massacres and bombings had been organised or promoted or supported by men inside Italian state institutions who were linked to American intelligence. The report also said the United States was guilty of promoting the strategy of tension. Operation Gladio is also suspected to have been activated to counter existing left-wing parliamentary majorities in Europe.

The US State Department published a communiqué in January 2006 that stated claims the United States ordered, supported, or authorized terrorism by stay-behind units, and US-sponsored "false flag" operations are rehashed former Soviet disinformation based on documents that the Soviets forged.

The word gladio is the Italian form of gladius, a type of Roman shortsword.

🔗 Cognitive science 🔗 Robotics

A cognitive architecture refers to both a theory about the structure of the human mind and to a computational instantiation of such a theory used in the fields of artificial intelligence (AI) and computational cognitive science. One of the main goals of a cognitive architecture is to summarize the various results of cognitive psychology in a comprehensive computer model. However, the results need to be formalized so far as they can be the basis of a computer program. The formalized models can be used to further refine a comprehensive theory of cognition, and more immediately, as a commercially usable model. Successful cognitive architectures include ACT-R (Adaptive Control of Thought - Rational) and SOAR.

The Institute for Creative Technologies defines cognitive architecture as: "hypothesis about the fixed structures that provide a mind, whether in natural or artificial systems, and how they work together – in conjunction with knowledge and skills embodied within the architecture – to yield intelligent behavior in a diversity of complex environments."

🔗 Apps

Send Me To Heaven (officially stylized as S.M.T.H.) is an Android application developed by Carrot Pop which measures the vertical distance that a mobile phone is thrown. Players compete against each other by seeking to throw their phones higher than others, often at the risk of damaging their phones. The app was immediately banned from the App Store but remains available from Google Play, where it maintains a cult following.