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🔗 Meteorology 🔗 Meteorology/weather data, products and instrumentation

The tempest prognosticator, also known as the leech barometer, is a 19th-century invention by George Merryweather in which leeches are used in a barometer. The twelve leeches are kept in small bottles inside the device; when they become agitated by an approaching storm they attempt to climb out of the bottles and trigger a small hammer which strikes a bell. The likelihood of a storm is indicated by the number of times the bell is struck.

🔗 Mass surveillance 🔗 Architecture 🔗 Philosophy 🔗 Philosophy/Social and political philosophy 🔗 Law Enforcement 🔗 Correction and Detention Facilities

The panopticon is a type of institutional building and a system of control designed by the English philosopher and social theorist Jeremy Bentham in the 18th century. The concept of the design is to allow all prisoners of an institution to be observed by a single security guard, without the inmates being able to tell whether they are being watched.

Although it is physically impossible for the single guard to observe all the inmates' cells at once, the fact that the inmates cannot know when they are being watched means that they are motivated to act as though they are being watched at all times. Thus, the inmates are effectively compelled to regulate their own behaviour. The architecture consists of a rotunda with an inspection house at its centre. From the centre the manager or staff of the institution are able to watch the inmates. Bentham conceived the basic plan as being equally applicable to hospitals, schools, sanatoriums, and asylums, but he devoted most of his efforts to developing a design for a panopticon prison. It is his prison that is now most widely meant by the term "panopticon".

🔗 Psychology

An autostereogram is a single-image stereogram (SIS), designed to create the visual illusion of a three-dimensional (3D) scene from a two-dimensional image. In order to perceive 3D shapes in these autostereograms, one must overcome the normally automatic coordination between accommodation (focus) and horizontal vergence (angle of one's eyes). The illusion is one of depth perception and involves stereopsis: depth perception arising from the different perspective each eye has of a three-dimensional scene, called binocular parallax.

The simplest type of autostereogram consists of horizontally repeating patterns (often separate images) and is known as a wallpaper autostereogram. When viewed with proper convergence, the repeating patterns appear to float above or below the background. The well-known Magic Eye books feature another type of autostereogram called a random dot autostereogram. One such autostereogram is illustrated above right. In this type of autostereogram, every pixel in the image is computed from a pattern strip and a depth map. A hidden 3D scene emerges when the image is viewed with the correct convergence.

Autostereograms are similar to normal stereograms except they are viewed without a stereoscope. A stereoscope presents 2D images of the same object from slightly different angles to the left eye and the right eye, allowing us to reconstruct the original object via binocular disparity. When viewed with the proper vergence, an autostereogram does the same, the binocular disparity existing in adjacent parts of the repeating 2D patterns.

There are two ways an autostereogram can be viewed: wall-eyed and cross-eyed. Most autostereograms (including those in this article) are designed to be viewed in only one way, which is usually wall-eyed. Wall-eyed viewing requires that the two eyes adopt a relatively parallel angle, while cross-eyed viewing requires a relatively convergent angle. An image designed for wall-eyed viewing if viewed correctly will appear to pop out of the background, while if viewed cross-eyed it will instead appear as a cut-out behind the background and may be difficult to bring entirely into focus.

🔗 Technology

Deep borehole disposal (DBD) is the concept of disposing high-level radioactive waste from nuclear reactors in extremely deep boreholes instead of in more traditional deep geological repositories that are excavated like mines. Deep borehole disposal seeks to place the waste as much as five kilometres (3.1 mi) beneath the surface of the Earth and relies primarily on the thickness of the natural geological barrier to safely isolate the waste from the biosphere for a very long period of time so that it should not pose a threat to humans and the environment. The concept was originally developed in the 1970s, but in 2014 a proposal for a first experimental borehole was proposed by a consortium headed by Sandia National Laboratories.

The waste would be put into the lower mile of such a hole, within crystalline rock to isolate it from the environment. The upper two miles of the borehole would be filled with protective layers including asphalt, bentonite, concrete and crushed rock that are expected to protect the environment during geologic time, and the hole would be lined with steel casing.

A pair of proposed test boreholes in the United States were cancelled due to public opposition and lack of funding in 2016 and 2017.

🔗 Philately

Rocket mail is the delivery of mail by rocket or missile. The rocket lands by deploying an internal parachute upon arrival. It has been attempted by various organizations in many different countries, with varying levels of success. It has never become widely seen as being a viable option for delivering mail, due to the cost of the schemes and numerous failures.

The collection of philatelic material ("stamps") used for (and depicting) rocket mail is part of a specialist branch of aerophilately known as astrophilately.

🔗 Computing 🔗 Computer science 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 Linux

OpenSSI is an open-source single-system image clustering system. It allows a collection of computers to be treated as one large system, allowing applications running on any one machine access to the resources of all the machines in the cluster.

OpenSSI is based on the Linux operating system and was released as an open source project by Compaq in 2001. It is the final stage of a long process of development, stretching back to LOCUS, developed in the early 1980s.

🔗 Biography 🔗 Energy 🔗 Pennsylvania 🔗 Lehigh Valley

Edwin Laurentine Drake (March 29, 1819 – November 9, 1880), also known as Colonel Drake, was an American businessman and the first American to successfully drill for oil.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Cold War

Blue Peacock, renamed from Blue Bunny and originally Brown Bunny, was a British tactical nuclear weapon project in the 1950s.

The project's goal was to store a number of ten-kiloton nuclear mines in Germany, to be placed on the North German Plain and, in the event of Soviet invasion from the east, detonated by wire or an eight-day timer to:

... not only destroy facilities and installations over a large area, but ... deny occupation of the area to an enemy for an appreciable time due to contamination ...

🔗 Microbiology

Archaeal Richmond Mine acidophilic nanoorganisms (ARMAN) were first discovered in an extremely acidic mine located in northern California (Richmond Mine at Iron Mountain) by Brett Baker in Jill Banfield's laboratory at the University of California Berkeley. These novel groups of archaea named ARMAN-1, ARMAN-2 (Candidatus Micrarchaeum acidiphilum ARMAN-2 ), and ARMAN-3 were missed by previous PCR-based surveys of the mine community because the ARMANs have several mismatches with commonly used PCR primers for 16S rRNA genes. Baker et al. detected them in a later study using shotgun sequencing of the community. The three groups were originally thought to represent three unique lineages deeply branched within the Euryarchaeota, a subgroup of the Archaea. However, this has been revised, based on more complete archaeal genomic tree, that they belong to a super phylum named DPANN. The ARMAN groups now comprise deeply divergent phyla named Micrarchaeota and Parvarchaeota. Their 16S rRNA genes differ by as much as 17% between the three groups. Prior to their discovery all of the Archaea shown to be associated with Iron Mountain belonged to the order Thermoplasmatales (e.g., Ferroplasma acidarmanus).

🔗 Physiology 🔗 Evolutionary biology

In evolutionary biology and evolutionary psychology, the Trivers–Willard hypothesis, formally proposed by Robert Trivers and Dan Willard in 1973, suggests that female mammals are able to adjust offspring sex ratio in response to their maternal condition. For example, it may predict greater parental investment in males by parents in "good conditions" and greater investment in females by parents in "poor conditions" (relative to parents in good condition). The reasoning for this prediction is as follows: Assume that parents have information on the sex of their offspring and can influence their survival differentially. While pressures exist to maintain sex ratios at 50%, evolution will favor local deviations from this if one sex has a likely greater reproductive payoff than is usual.

Trivers and Willard also identified a circumstance in which reproducing individuals might experience deviations from expected offspring reproductive value—namely, varying maternal condition. In polygynous species males may mate with multiple females and low-condition males will achieve fewer or no matings. Parents in relatively good condition would then be under selection for mutations causing production and investment in sons (rather than daughters), because of the increased chance of mating experienced by these good-condition sons. Mating with multiple females conveys a large reproductive benefit, whereas daughters could translate their condition into only smaller benefits. An opposite prediction holds for poor-condition parents—selection will favor production and investment in daughters, so long as daughters are likely to be mated, while sons in poor condition are likely to be out-competed by other males and end up with zero mates (i.e., those sons will be a reproductive dead end).

The hypothesis was used to explain why, for example, Red Deer mothers would produce more sons when they are in good condition, and more daughters when in poor condition. In polyandrous species where some females mate with multiple males (and others get no matings) and males mate with one/few females (i.e., "sex-role reversed" species), these predictions from the Trivers–Willard hypothesis are reversed: parents in good condition will invest in daughters in order to have a daughter that can out-compete other females to attract multiple males, whereas parents in poor condition will avoid investing in daughters who are likely to get out-competed and will instead invest in sons in order to gain at least some grandchildren.

"Condition" can be assessed in multiple ways, including body size, parasite loads, or dominance, which has also been shown in macaques (Macaca sylvanus) to affect the sex of offspring, with dominant females giving birth to more sons and non-dominant females giving birth to more daughters. Consequently, high-ranking females give birth to a higher proportion of males than those who are low-ranking.

In their original paper, Trivers and Willard were not yet aware of the biochemical mechanism for the occurrence of biased sex ratios. Eventually, however, Melissa Larson et al. (2001) proposed that a high level of circulating glucose in the mother's bloodstream may favor the survival of male blastocysts. This conclusion is based on the observed male-skewed survival rates (to expanded blastocyst stages) when bovine blastocysts were exposed to heightened levels of glucose. As blood glucose levels are highly correlated with access to high-quality food, blood glucose level may serve as a proxy for "maternal condition". Thus, heightened glucose functions as one possible biochemical mechanism for observed Trivers–Willard effects.

Wild and West published a paper describing a mathematical model built on the Trivers–Willard hypothesis that allows precise predictions of alterations in sex-ratio under different circumstances.