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🔗 Military history 🔗 Military history/World War II 🔗 Scottish Islands

Operation Vegetarian was a British military plan in 1942 to disseminate linseed cakes infected with anthrax spores onto the fields of Germany. These cakes would have been eaten by the cattle, which would then be consumed by the civilian population, causing the deaths of millions of German citizens. Furthermore, it would have wiped out the majority of Germany's cattle, creating a massive food shortage for the rest of the population that remained uninfected. Preparations were not complete until early 1944. Operation Vegetarian was only to be used in the event of a German anthrax attack on the United Kingdom.

The cakes themselves were tested on Gruinard Island, just off the coast of Scotland. Because of the widespread contamination from the anthrax spores, the land remained quarantined until 1990. The five million cakes made to be disseminated in Germany were eventually destroyed in an incinerator shortly after the end of World War II.

In his novel The Impossible Dead (2011), author Ian Rankin mentions the clandestine events surrounding the removal of contaminated soils from Guinard Island by a protest group, the Dark Harvest Commando, and the island's removal from maps by the British Government. The island also features as the principal setting for the 1985 novel El año de gracia, by Cristina Fernández Cubas, in which the protagonist spends a winter shipwrecked on the island.

🔗 Color 🔗 Physiology

Eigengrau (German: "intrinsic gray", lit. "own gray"; pronounced [ˈʔaɪ̯gn̩ˌgʁaʊ̯]), also called Eigenlicht (Dutch and German: "own light"), dark light, or brain gray, is the uniform dark gray background that many people report seeing in the absence of light. The term Eigenlicht dates back to the nineteenth century, but has rarely been used in recent scientific publications. Common scientific terms for the phenomenon include "visual noise" or "background adaptation". These terms arise due to the perception of an ever-changing field of tiny black and white dots seen in the phenomenon.

Eigengrau is perceived as lighter than a black object in normal lighting conditions, because contrast is more important to the visual system than absolute brightness. For example, the night sky looks darker than Eigengrau because of the contrast provided by the stars.

🔗 Biography 🔗 Chicago 🔗 Biography/Actors and Filmmakers 🔗 College Basketball

John Michael Crichton (; October 23, 1942 – November 4, 2008) was an American author, screenwriter, film director, and film producer. His books have sold over 200 million copies worldwide, and over a dozen have been adapted into films. His literary works are usually within the science fiction, techno-thriller, and medical fiction genres, and heavily feature technology. His novels often explore technology and failures of human interaction with it, especially resulting in catastrophes with biotechnology. Many of his novels have medical or scientific underpinnings, reflecting his medical training and scientific background. He wrote, among other works, The Andromeda Strain (1969), The Great Train Robbery (1975), Congo (1980), Sphere (1987), Jurassic Park (1990), Rising Sun (1992), Disclosure (1994), The Lost World (1995), Airframe (1996), Timeline (1999), Prey (2002), State of Fear (2004), and Next (2006). Films he wrote and directed included Westworld (1973), Coma (1978), The Great Train Robbery (1979), Looker (1981), and Runaway (1984).

🔗 Mathematics

Bellman's lost-in-a-forest problem is an unsolved minimization problem in geometry, originating in 1955 by the American applied mathematician Richard E. Bellman. The problem is often stated as follows: "A hiker is lost in a forest whose shape and dimensions are precisely known to him. What is the best path for him to follow to escape from the forest?" It is usually assumed that the hiker does not know the starting point or direction he is facing. The best path is taken to be the one that minimizes the worst-case distance to travel before reaching the edge of the forest. Other variations of the problem have been studied.

A proven solution is only known for a few shapes or classes of shape. A general solution would be in the form of a geometric algorithm which takes the shape of the forest as input and returns the optimal escape path as the output. Although real world applications are not apparent, the problem falls into a class of geometric optimization problems including search strategies that are of practical importance. A bigger motivation for study has been the connection to Moser's worm problem. It was included in a list of 12 problems described by the mathematician Scott W. Williams as "million buck problems" because he believed that the techniques involved in their resolution will be worth at least a million dollars to mathematics.

🔗 Spaceflight 🔗 Moon

The Apollo 11 missing tapes were those that were recorded from Apollo 11's slow-scan television (SSTV) telecast in its raw format on telemetry data tape at the time of the first Moon landing in 1969 and subsequently lost. The data tapes were recorded as a backup in case the live television broadcasts failed for any reason.

To broadcast the SSTV transmission on standard television, NASA ground receiving stations performed real-time scan conversion to the NTSC television format. The moonwalk's converted video signal was broadcast live around the world on July 21, 1969 (2:56 UTC). At the time, the NTSC broadcast was recorded on many videotapes and kinescope films. Many of these low-quality recordings remain intact. As the real-time broadcast worked and was widely recorded, preservation of the backup video was not deemed a priority in the years immediately following the mission. In the early 1980s, NASA's Landsat program was facing a severe data tape shortage and it is likely the tapes were erased and reused at this time.

A team of retired NASA employees and contractors tried to find the tapes in the early 2000s but was unable to do so. The search was sparked when several still photographs appeared in the late 1990s that showed the visually superior raw SSTV transmission on ground-station monitors. The research team conducted a multi-year investigation in the hopes of finding the most pristine and detailed video images of the moonwalk. If copies of the original SSTV format tapes were to be found, more modern digital technology could make a higher-quality conversion, yielding better images than those originally seen. The researchers concluded that the tapes containing the raw unprocessed Apollo 11 SSTV signal were erased and reused by NASA in the early 1980s, following standard procedure at the time.

Although the researchers never found the telemetry tapes, they did discover the best visual quality NTSC videotapes as well as Super 8 movie film taken of a video monitor in Australia, showing the SSTV transmission before it was converted. These visual elements were processed in 2009, as part of a NASA-approved restoration project of the first moonwalk. At a 2009 news conference in Washington, D.C., the research team released its findings regarding the tapes' disappearance. They also partially released newly enhanced footage obtained during the search. Lowry Digital completed the full moonwalk restoration project in late 2009.

🔗 Internet

Cicada 3301 is a nickname given to an organization that on three occasions has posted a set of puzzles to recruit codebreakers from the public. The first internet puzzle started on January 4, 2012 on 4chan and ran for approximately one month. A second round began one year later on January 4, 2013, and then a third round following the confirmation of a fresh clue posted on Twitter on January 4, 2014. The stated intent was to recruit "intelligent individuals" by presenting a series of puzzles which were to be solved. No new puzzles were published on January 4, 2015. However, a new clue was posted on Twitter on January 5, 2016. In April 2017 a verified PGP-signed message was found: Beware false paths. Always verify PGP signature from 7A35090F. That message explicitly denies the validity of any unsigned puzzle, as recently as April 2017.

The puzzles focused heavily on data security, cryptography, steganography, internet anonymity, and surveillance.

It has been called "the most elaborate and mysterious puzzle of the internet age" and is listed as one of the "top 5 eeriest, unsolved mysteries of the internet", and much speculation exists as to its function. Many have speculated that the puzzles are a recruitment tool for the NSA, CIA, MI6, a "Masonic conspiracy" or a cyber mercenary group. Others have claimed Cicada 3301 is an alternate reality game. No company or individual has taken credit for it or attempted to monetize it, however.

🔗 Rome

Secessio plebis (withdrawal of the commoners, or secession of the plebs) was an informal exercise of power by Rome's plebeian citizens, similar in concept to the general strike. During the secessio plebis, the plebs would abandon the city en masse and leave the patrician order to themselves. Therefore, a secessio meant that all shops and workshops would shut down and commercial transactions would largely cease. This was an effective strategy in the Conflict of the Orders due to strength in numbers; plebeian citizens made up the vast majority of Rome's populace and produced most of its food and resources, while a patrician citizen was a member of the minority upper class, the equivalent of the landed gentry of later times. Authors report different numbers for how many secessions there were. Cary & Scullard state there were five between 494 BC and 287 BC.

🔗 History 🔗 Philosophy 🔗 Palaeontology 🔗 Geology 🔗 Archaeology

The Silurian hypothesis is a thought experiment which assesses modern science's ability to detect evidence of a prior advanced civilization, perhaps several million years ago. In a 2018 paper, Adam Frank, an astrophysicist at the University of Rochester, and Gavin Schmidt, director of the NASA Goddard Institute, imagined an advanced civilization before humans and pondered whether it would "be possible to detect an industrial civilization in the geological record". They wrote, "While we strongly doubt that any previous industrial civilization existed before our own, asking the question in a formal way that articulates explicitly what evidence for such a civilization might look like raises its own useful questions related both to astrobiology and to Anthropocene studies." The term "silurian hypothesis" was inspired by a 1970s Dr Who serial Doctor Who and the Silurians which featured a species called the Silurians.

According to Frank and Schmidt, since fossilization is relatively rare and little of Earth's exposed surface is from before the quaternary time period, the chances of finding direct evidence of such a civilization, such as technological artifacts, is small. After a great time span, the researchers concluded, we would be more likely to find indirect evidence such as anomalies in the chemical composition or isotope ratios of sediments. Objects that could indicate possible evidence of past civilizations include plastics and nuclear wastes residues buried deep underground or on the ocean floor.

Prior civilizations could have gone to space and left artifacts on other celestial bodies, such as the Moon and Mars. Evidence for artifacts on these two worlds would be easier to find than on Earth, where erosion and tectonic activity would erase much of it.

Frank first approached Schmidt to discuss how to detect alien civilizations via their potential impact upon climate through the study of ice cores and tree rings. They both realized that the hypothesis could be expanded and applied to Earth and humanity due to the fact that humans have been in their current form for the past 300,000 years and have had sophisticated technology for only the last few centuries.

🔗 Mathematics 🔗 Physics 🔗 Systems 🔗 Systems/Dynamical systems

The Abelian sandpile model, also known as the Bak–Tang–Wiesenfeld model, was the first discovered example of a dynamical system displaying self-organized criticality. It was introduced by Per Bak, Chao Tang and Kurt Wiesenfeld in a 1987 paper.

The model is a cellular automaton. In its original formulation, each site on a finite grid has an associated value that corresponds to the slope of the pile. This slope builds up as "grains of sand" (or "chips") are randomly placed onto the pile, until the slope exceeds a specific threshold value at which time that site collapses transferring sand into the adjacent sites, increasing their slope. Bak, Tang, and Wiesenfeld considered process of successive random placement of sand grains on the grid; each such placement of sand at a particular site may have no effect, or it may cause a cascading reaction that will affect many sites.

The model has since been studied on the infinite lattice, on other (non-square) lattices, and on arbitrary graphs (including directed multigraphs). It is closely related to the dollar game, a variant of the chip-firing game introduced by Biggs.

🔗 Computing 🔗 Computing/Computer hardware

Viewtron was an online service offered by Knight-Ridder and AT&T from 1983 to 1986. Patterned after the British Post Office's Prestel system, it started as a videotex service requiring users to have a special terminal, the AT&T Sceptre. As home computers became important in the marketplace, the development focus shifted to IBM, Apple, Commodore and other personal computers.

Viewtron differed from contemporary services like CompuServe and The Source by emphasizing news from The Miami Herald and Associated Press and e-commerce services from JCPenney and other merchants over computer-oriented services such as file downloads or online chat. Intended to be "the McDonald's of videotex," Viewtron was specifically targeted toward users who would be apprehensive about using a computer.

Viewtron also offered airline schedules from the Official Airline Guide (OAG), real estate research from Century 21, e-cards from Hallmark, product information from Consumer Reports, educational software from Scott Foresman, online auctions, financial services from American Express and EF Hutton, as well as limited online banking services as part of a research program into the uses and costs of banking online that included 20 US and Canadian banks.

At its height, Viewtron was operated in at least 15 cities by various newspaper companies. After six years of research and an investment reportedly in excess of $50 million, Viewtron never turned a profit, and, despite its developer's forecasts of breaking even in two years, Knight Ridder did not expect it ever would be profitable. AT&T had invested over $100 million in the project, but was forced to write off that investment as part of its court-ordered breakup. Viewtron closed on March 31, 1986, after an attempt by the Independent Commodore Users Group to buy the service failed.

A feature tying Viewtron to local newspapers was envisioned, with printed text instructing users how to access further information online, but it was never implemented.

In 2008, PCWorld magazine named Viewtron to a list of the biggest project failures in information technology (IT) history.