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🔗 California 🔗 Skepticism 🔗 Geography 🔗 Alternative Views 🔗 Geology

Sailing stones (also known as sliding rocks, walking rocks, rolling stones, and moving rocks), are a geological phenomenon where rocks move and inscribe long tracks along a smooth valley floor without human or animal intervention. The movement of the rocks occurs when large ice sheets a few millimeters thick and floating in an ephemeral winter pond start to break up during sunny days. Frozen during cold winter nights, these thin floating ice panels are driven by wind and shove rocks at speeds up to 5 meters per minute.

Trails of sliding rocks have been observed and studied in various locations, including Little Bonnie Claire Playa in Nevada, and most famously at Racetrack Playa, Death Valley National Park, California, where the number and length of tracks are notable.

🔗 Israel 🔗 Apps

Yo is a social mobile application for iOS, Android, and formerly also Windows Phone. Initially, the application's only function was to send the user's friends the word "yo" as a text and audio notification, but it has since been updated to enable users to attach links and location to their "Yo"s.

🔗 France 🔗 Military history 🔗 Politics 🔗 Military history/Intelligence 🔗 Judaism 🔗 Military history/French military history 🔗 Jewish history 🔗 European history 🔗 Military history/European military history

The Dreyfus Affair (French: l'affaire Dreyfus, pronounced [lafɛːʁ dʁɛfys]) was a political scandal that divided the Third French Republic from 1894 until its resolution in 1906. "The Affair", as it is known in French, has come to symbolise modern injustice in the Francophone world, and it remains one of the most notable examples of a complex miscarriage of justice and antisemitism. The role played by the press and public opinion proved influential in the conflict.

The scandal began in December 1894 when Captain Alfred Dreyfus was convicted of treason. Dreyfus was a 35-year-old Alsatian French artillery officer of Jewish descent. He was sentenced to life imprisonment for allegedly communicating French military secrets to the German Embassy in Paris, and was imprisoned on Devil's Island in French Guiana, where he spent nearly five years.

In 1896, evidence came to light—primarily through an investigation instigated by Georges Picquart, head of counter-espionage—which identified the real culprit as a French Army major named Ferdinand Walsin Esterhazy. When high-ranking military officials suppressed the new evidence, a military court unanimously acquitted Esterhazy after a trial lasting only two days. The Army laid additional charges against Dreyfus, based on forged documents. Subsequently, Émile Zola's open letter J'Accuse…!, stoked a growing movement of support for Dreyfus, putting pressure on the government to reopen the case.

In 1899, Dreyfus was returned to France for another trial. The intense political and judicial scandal that ensued divided French society between those who supported Dreyfus (now called "Dreyfusards"), such as Sarah Bernhardt, Anatole France, Henri Poincaré and Georges Clemenceau, and those who condemned him (the anti-Dreyfusards), such as Édouard Drumont, the director and publisher of the antisemitic newspaper La Libre Parole. The new trial resulted in another conviction and a 10-year sentence, but Dreyfus was pardoned and released. In 1906, Dreyfus was exonerated and reinstated as a major in the French Army. He served during the whole of World War I, ending his service with the rank of lieutenant-colonel. He died in 1935.

The affair from 1894 to 1906 divided France into pro-republican, anticlerical, Dreyfusards and pro-Army, mostly Catholic "anti-Dreyfusards". It embittered French politics and encouraged radicalisation.

🔗 Computing 🔗 Computing/Networking

The Secure Remote Password protocol (SRP) is an augmented password-authenticated key agreement (PAKE) protocol, specifically designed to work around existing patents.

Like all PAKE protocols, an eavesdropper or man in the middle cannot obtain enough information to be able to brute force guess a password without further interactions with the parties for each guess. Furthermore, being an augmented PAKE protocol, the server does not store password-equivalent data. This means that an attacker who steals the server data cannot masquerade as the client unless they first perform a brute force search for the password.

In layman's terms, during SRP (or any other PAKE protocol) authentication, one party (the "client" or "user") demonstrates to another party (the "server") that they know the password, without sending the password itself nor any other information from which the password can be derived. The password never leaves the client and is unknown to the server.

Furthermore, the server also needs to know about the password (but not the password itself) in order to instigate the secure connection. This means that the server also authenticates itself to the client, without reliance on the user parsing complex URLs. This prevents Phishing.

🔗 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.

🔗 Computer science 🔗 Philosophy 🔗 Psychology 🔗 Philosophy/Social and political philosophy 🔗 Philosophy/Philosophy of science 🔗 Philosophy/Contemporary philosophy 🔗 Philosophy/Philosophy of mind 🔗 Sociology 🔗 Cultural Evolution

Memetics is a theory of the evolution of culture based on Darwinian principles with the meme as the unit of culture. The term "meme" was coined by biologist Richard Dawkins in his 1976 book The Selfish Gene, to illustrate the principle that he later called "Universal Darwinism". All evolutionary processes depend on information being copied, varied, and selected, a process also known as variation with selective retention. The information that is copied is called the replicator, and genes are the replicator for biological evolution. Dawkins proposed that the same process drives cultural evolution, and he called this second replicator the "meme". He gave as examples, tunes, catchphrases, fashions, and technologies. Like genes, memes are selfish replicators and have causal efficacy; in other words, their properties influence their chances of being copied and passed on. Some succeed because they are valuable or useful to their human hosts while others are more like viruses.

Just as genes can work together to form co-adapted gene complexes, so groups of memes acting together form co-adapted meme complexes or memeplexes. Memeplexes include (among many other things) languages, traditions, scientific theories, financial institutions, and religions. Dawkins famously referred to religions as "viruses of the mind".

Among proponents of memetics are psychologist Susan Blackmore, author of The Meme Machine, who argues that when our ancestors began imitating behaviours, they let loose a second replicator and co-evolved to become the "meme machines" that copy, vary, and select memes in culture. Philosopher Daniel Dennett develops memetics extensively, notably in his books Darwin's Dangerous Idea, and From Bacteria to Bach and Back. He describes the units of memes as "the smallest elements that replicate themselves with reliability and fecundity." and claims that "Human consciousness is itself a huge complex of memes." In The Beginning of Infinity, physicist David Deutsch contrasts static societies that depend on anti-rational memes suppressing innovation and creativity, with dynamic societies based on rational memes that encourage enlightenment values, scientific curiosity, and progress.

Criticisms of memetics include claims that memes do not exist, that the analogy with genes is false, that the units cannot be specified, that culture does not evolve through imitation, and that the sources of variation are intelligently designed rather than random. Critics of memetics include biologist Stephen Jay Gould who calls memetics a "meaningless metaphor". Philosopher Dan Sperber argues against memetics as a viable approach to cultural evolution because cultural items are not directly copied or imitated but are reproduced. Anthropologist Robert Boyd and biologist Peter Richerson work within the alternative, and more mainstream, field of cultural evolution theory and gene-culture coevolution. Dual inheritance theory has much in common with memetics but rejects the idea that memes are replicators. From this perspective, memetics is seen as just one of several approaches to cultural evolution and one that is generally considered less useful than the alternatives of gene-culture coevolution or dual inheritance theory. The main difference is that dual inheritance theory ultimately depends on biological advantage to genes, whereas memetics treats memes as a second replicator in its own right. Memetics also extends to the analysis of Internet culture and Internet memes.

🔗 California 🔗 California/San Francisco Bay Area 🔗 Computing 🔗 Stanford University/SRI International 🔗 Stanford University

"The Mother of All Demos" is a name retroactively applied to a landmark computer demonstration, given at the Association for Computing Machinery / Institute of Electrical and Electronics Engineers (ACM/IEEE)—Computer Society's Fall Joint Computer Conference in San Francisco, which was presented by Douglas Engelbart on December 9, 1968.

The live demonstration featured the introduction of a complete computer hardware and software system called the oN-Line System or, more commonly, NLS. The 90-minute presentation essentially demonstrated almost all the fundamental elements of modern personal computing: windows, hypertext, graphics, efficient navigation and command input, video conferencing, the computer mouse, word processing, dynamic file linking, revision control, and a collaborative real-time editor (collaborative work). Engelbart's presentation was the first to publicly demonstrate all of these elements in a single system. The demonstration was highly influential and spawned similar projects at Xerox PARC in the early 1970s. The underlying technologies influenced both the Apple Macintosh and Microsoft Windows graphical user interface operating systems in the 1980s and 1990s.

🔗 Russia 🔗 Disaster management 🔗 Terrorism 🔗 Russia/politics and law of Russia 🔗 Russia/history of Russia

The Russian apartment bombings were a series of explosions that hit four apartment blocks in the Russian cities of Buynaksk, Moscow and Volgodonsk in September 1999, killing more than 300, injuring more than 1000, and spreading a wave of fear across the country. The bombings, together with the Invasion of Dagestan, triggered the Second Chechen War. Then-prime minister Vladimir Putin's handling of the crisis boosted his popularity greatly and helped him attain the presidency within a few months. Russian courts ruled that the attacks were orchestrated by Chechen-linked militants, while some scholars, journalists, and politicians have argued that Russian security services likely organized the bombings.

The blasts hit Buynaksk on 4 September and in Moscow on 9 and 13 September. On 13 September, Russian Duma speaker Gennadiy Seleznyov made an announcement in the Duma about receiving a report that another bombing had just happened in the city of Volgodonsk. A bombing did indeed happen in Volgodonsk, but only three days later, on 16 September. Chechen militants were blamed for the bombings, but denied responsibility, along with Chechen president Aslan Maskhadov.

A suspicious device resembling those used in the bombings was found and defused in an apartment block in the Russian city of Ryazan on 22 September. On 23 September, Vladimir Putin praised the vigilance of the inhabitants of Ryazan and ordered the air bombing of Grozny, which marked the beginning of the Second Chechen War. Three FSB agents who had planted the devices at Ryazan were arrested by the local police. On 24 September 1999, head of FSB Nikolay Patrushev announced that the incident in Ryazan had been an anti-terror drill and the device found there contained only sugar.

The official Russian investigation of the Buynaksk bombing was completed in 2000, while the investigation of Moscow and Volgodonsk bombings was completed in 2002. In 2000, seven people were convicted of perpetrating the Buinaksk attack. According to the court ruling on the Moscow and Volgodonsk bombings, which was announced in 2004, the attacks were organised and led by Achemez Gochiyaev, who remains at large. All bombings, the court ruled, were ordered by Islamist warlords Ibn Al-Khattab and Abu Omar al-Saif, who have been killed. Five other suspects have been killed and six have been convicted by Russian courts on terrorism-related charges.

Parliament member Yuri Shchekochikhin filed two motions for a parliamentary investigation of the events, but the motions were rejected by the Russian Duma in March 2000. An independent public commission to investigate the bombings was chaired by Duma deputy Sergei Kovalev. The commission was rendered ineffective because of government refusal to respond to its inquiries. Two key members of the Kovalev Commission, Sergei Yushenkov and Yuri Shchekochikhin, have since died in apparent assassinations. The Commission’s lawyer and investigator Mikhail Trepashkin was arrested and served four years in prison for revealing state secrets. Former FSB agent Alexander Litvinenko, who defected and blamed the FSB for the bombings, was poisoned and killed in London in 2006. A British inquiry later determined that Litvinenko's murder was "probably" carried out with the approval of Putin and Patrushev.

The 1999 attacks were officially attributed to Chechen terrorists. According to some historians and journalists, the bombings were coordinated by the Russian state security services to bring Putin into the presidency. Others disagree with such theories. Independent investigations have faced obstruction from Russian security services, raising further suspicions about their involvement in the attacks.

🔗 Computing 🔗 Computer science 🔗 Computing/Software 🔗 Computing/Computer science

Comb sort is a relatively simple sorting algorithm originally designed by Włodzimierz Dobosiewicz and Artur Borowy in 1980, later rediscovered by Stephen Lacey and Richard Box in 1991. Comb sort improves on bubble sort.

🔗 Technology 🔗 Physics 🔗 Neuroscience 🔗 Molecular Biology 🔗 Molecular Biology/Molecular and Cell Biology

Confocal microscopy, most frequently confocal laser scanning microscopy (CLSM) or laser scanning confocal microscopy (LSCM), is an optical imaging technique for increasing optical resolution and contrast of a micrograph by means of using a spatial pinhole to block out-of-focus light in image formation. Capturing multiple two-dimensional images at different depths in a sample enables the reconstruction of three-dimensional structures (a process known as optical sectioning) within an object. This technique is used extensively in the scientific and industrial communities and typical applications are in life sciences, semiconductor inspection and materials science.

Light travels through the sample under a conventional microscope as far into the specimen as it can penetrate, while a confocal microscope only focuses a smaller beam of light at one narrow depth level at a time. The CLSM achieves a controlled and highly limited depth of field.