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๐ Nematode revived after 46,000 years in Siberian permafrost
The nematodes ( NEM-ษ-tohdz or NEEM-; Greek: ฮฮทฮผฮฑฯฯฮดฮท; Latin: Nematoda) roundworms or eelworms, constitute the phylum Nematoda. They are a diverse animal phylum inhabiting a broad range of environments. Most species are free-living, feeding on microorganisms, but there are many that are parasitic. The parasitic worms (helminths) are the cause of soil-transmitted helminthiases.
They are taxonomically classified along with arthropods, tardigrades and other moulting animals in the clade Ecdysozoa. Unlike the vaguely similar flatworms, nematodes have a tubular digestive system, with openings at both ends. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum.
Nematode species can be difficult to distinguish from one another. Consequently, estimates of the number of nematode species are uncertain. A 2013 survey of animal biodiversity published in the mega journal Zootaxa puts this figure at over 25,000. Estimates of the total number of extant species are subject to even greater variation. A widely referenced article published in 1993 estimated there may be over 1ย million species of nematode. A subsequent publication challenged this claim, estimating the figure to be at least 40,000ย species. Although the highest estimates (up to 100 million species) have since been deprecated, estimates supported by rarefaction curves, together with the use of DNA barcoding and the increasing acknowledgment of widespread cryptic species among nematodes, have placed the figure closer to 1ย million species.
Nematodes have successfully adapted to nearly every ecosystem: from marine (salt) to fresh water, soils, from the polar regions to the tropics, as well as the highest to the lowest of elevations. They are ubiquitous in freshwater, marine, and terrestrial environments, where they often outnumber other animals in both individual and species counts, and are found in locations as diverse as mountains, deserts, and oceanic trenches. They are found in every part of the earth's lithosphere, even at great depths, 0.9โ3.6ย km (3,000โ12,000ย ft) below the surface of the Earth in gold mines in South Africa. They represent 90% of all animals on the ocean floor. In total, 4.4 ร 1020 nematodes inhabit the Earth's topsoil, or approximately 60ย billion for each human, with the highest densities observed in tundra and boreal forests. Their numerical dominance, often exceeding a million individuals per square meter and accounting for about 80% of all individual animals on earth, their diversity of lifecycles, and their presence at various trophic levels point to an important role in many ecosystems. They have been shown to play crucial roles in polar ecosystems. The roughly 2,271ย genera are placed in 256ย families. The many parasitic forms include pathogens in most plants and animals. A third of the genera occur as parasites of vertebrates; about 35ย nematode species occur in humans.
Nathan Cobb, a nematologist, described the ubiquity of nematodes on Earth thus:
In short, if all the matter in the universe except the nematodes were swept away, our world would still be dimly recognizable, and if, as disembodied spirits, we could then investigate it, we should find its mountains, hills, vales, rivers, lakes, and oceans represented by a film of nematodes. The location of towns would be decipherable since, for every massing of human beings, there would be a corresponding massing of certain nematodes. Trees would still stand in ghostly rows representing our streets and highways. The location of the various plants and animals would still be decipherable, and, had we sufficient knowledge, in many cases even their species could be determined by an examination of their erstwhile nematode parasites.(pโฏ472)
๐ Razor 1911
Razor 1911 (RZR) is a warez and demogroup founded in Norway, 1986. It was the first ever such group to be initially founded exclusively as a demogroup, before moving into warez in 1987. According to the US Justice Department, Razor 1911 is the oldest software cracking group that is still active on the internet. Razor 1911 ran the diskmag 'Propaganda' until 1995.
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- "Razor 1911" | 2023-10-30 | 242 Upvotes 118 Comments
๐ Bakhshali Manuscript
The Bakhshali manuscript is an ancient Indian mathematical text written on birch bark that was found in 1881 in the village of Bakhshali, Mardan (near Peshawar in present-day Pakistan, historical Gandhara). It is perhaps "the oldest extant manuscript in Indian mathematics". For some portions a carbon-date was proposed of AD 224โ383 while for other portions a carbon-date as late as AD 885โ993 in a recent study, but the dating has been criticised by specialists on methodological grounds (Plofker et al. 2017 and Houben 2018 ยง3). The manuscript contains the earliest known Indian use of a zero symbol. It is written in a form of literary Sanskrit influenced by contemporary dialects.
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- "Bakhshali Manuscript" | 2023-10-30 | 94 Upvotes 24 Comments
๐ Poltergeist Anti Pattern
In computer programming, a poltergeist (or gypsy wagon) is a short-lived, typically stateless object used to perform initialization or to invoke methods in another, more permanent class. It is considered an anti-pattern. The original definition is by Michael Akroyd 1996 - Object World West Conference:
- "As a gypsy wagon or a poltergeist appears and disappears mysteriously, so does this short lived object. As a consequence the code is more difficult to maintain and there is unnecessary resource waste. The typical cause for this anti-pattern is poor object design."
A poltergeist can often be identified by its name; they are often called "manager_", "controller_", "supervisor", "start_process", etc.
Sometimes, poltergeist classes are created because the programmer anticipated the need for a more complex architecture. For example, a poltergeist arises if the same method acts as both the client and invoker in a command pattern, and the programmer anticipates separating the two phases. However, this more complex architecture may actually never materialize.
Poltergeists should not be confused with long-lived, state-bearing objects of a pattern such as modelโviewโcontroller, or tier-separating patterns such as business-delegate.
To remove a poltergeist, delete the class and insert its functionality in the invoked class, possibly by inheritance or as a mixin.
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- "Poltergeist Anti Pattern" | 2023-10-30 | 12 Upvotes 2 Comments
๐ Disappearing Polymorphs
In materials science, disappearing polymorphs (or perverse polymorphism) describes a phenomenon in which a seemingly stable crystal structure is suddenly unable to be produced, instead transforming into a polymorph, or differing crystal structure with the same chemical composition, during nucleation. Sometimes the resulting transformation is extremely hard or impractical to reverse, because the new polymorph may be more stable. It is hypothesized that contact with a single microscopic seed crystal of the new polymorph can be enough to start a chain reaction causing the transformation of a much larger mass of material. Widespread contamination with such microscopic seed crystals may lead to the impression that the original polymorph has "disappeared."
This is of concern to both the pharmaceutical and computer hardware industry, where disappearing polymorphs can ruin the effectiveness of their products, and make it impossible to manufacture the original product if there is any contamination. There have been cases of laboratories growing crystals of a particular structure and when they try to recreate this, the original crystal structure isn't created but a new crystal structure is. The drug paroxetine was subject to a lawsuit that hinged on such a pair of polymorphs, and multiple life-saving drugs, such as ritonavir, have been recalled due to unexpected polymorphism. Although it may seem like a so-called disappearing polymorph has disappeared for good, it is believed that it is always possible in principle to reconstruct the original polymorph, though doing so may be impractically difficult. Disappearing polymorphs are generally metastable forms, that are replaced by a more stable form.
It is hypothesized that "unintentional seeding" may also be responsible for the phenomenon in which it often becomes easier to crystallize synthetic compounds over time.
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- "Disappearing Polymorphs" | 2023-10-29 | 173 Upvotes 56 Comments
๐ Pemmican
Pemmican (also pemican in older sources) is a mixture of tallow, dried meat, and sometimes dried berries. A calorie-rich food, it can be used as a key component in prepared meals or eaten raw. Historically, it was an important part of indigenous cuisine in certain parts of North America and it is still prepared today. The word comes from the Cree word แฑแฆแฆแณแ (pimรฎhkรขn), which is derived from the word แฑแฅแ (pimรฎ), "fat, grease". The Lakota (or Sioux) word is wasnรก, originally meaning "grease derived from marrow bones", with the wa- creating a noun, and snรก referring to small pieces that adhere to something. It was invented by the Indigenous peoples of North America.
Pemmican was widely adopted as a high-energy food by Europeans involved in the fur trade and later by Arctic and Antarctic explorers, such as Captain Robert Bartlett, Ernest Shackleton, Richard E. Byrd, Fridtjof Nansen, Robert Falcon Scott, George W. DeLong, and Roald Amundsen.
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- "Pemmican" | 2023-10-29 | 33 Upvotes 12 Comments
๐ The Edison Disc Record
The Edison Diamond Disc Record is a type of phonograph record marketed by Thomas A. Edison, Inc. on their Edison Record label from 1912 to 1929. They were named Diamond Discs because the matching Edison Disc Phonograph was fitted with a permanent conical diamond stylus for playing them. Diamond Discs were incompatible with lateral-groove disc record players, e.g. the Victor Victrola, the disposable steel needles of which would damage them while extracting hardly any sound. Uniquely, they are just under 1โ4ย in (6.0ย mm; 0.235ย in) thick.
Edison had previously made only phonograph cylinders but decided to add a disc format to the product line because of the increasingly dominant market share of the shellac disc records (later called 78s because of their typical rotational speed in revolutions per minute) made by competitors such as the Victor Talking Machine Company. Victor and most other makers recorded and played sound by a lateral or side-to-side motion of the stylus in the record groove, while in the Edison system the motion was vertical or up-and-down, known as vertical recording, as used for cylinder records. An Edison Disc Phonograph is distinguished by the diaphragm of the reproducer being parallel to the surface of the record. The diaphragm of a reproducer used for playing lateral records is at a right angle to the surface.
In the late summer and early fall of 1929 Edison also briefly produced a high-quality series of thin electrically recorded lateral-cut "Needle Type" disc records for use on standard record players.
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- "The Edison Disc Record" | 2023-10-26 | 13 Upvotes 3 Comments
๐ Tierra (Computer Simulation)
Tierra is a computer simulation developed by ecologist Thomas S. Ray in the early 1990s in which computer programs compete for time (central processing unit (CPU) time) and space (access to main memory). In this context, the computer programs in Tierra are considered to be evolvable and can mutate, self-replicate and recombine. Tierra's virtual machine is written in C. It operates on a custom instruction set designed to facilitate code changes and reordering, including features such as jump to template (as opposed to the relative or absolute jumps common to most instruction sets).
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- "Tierra (Computer Simulation)" | 2023-10-28 | 15 Upvotes 1 Comments
๐ Quindar Tones
Quindar tones, most often referred to as the "beeps" that were heard during the American Apollo space missions, were a means by which remote transmitters on Earth were turned on and off so that the capsule communicator (CapCom) could communicate with the crews of the spacecraft. It was a means of in-band signaling to simulate the action of the push-to-talk and release-to-listen (often referred to as PTT) button commonly found on two-way radio systems and walkie-talkies.
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- "Quindar Tones" | 2023-10-28 | 14 Upvotes 5 Comments
๐ Sinosphere
The Sinosphere, also known as the East Asian cultural sphere, or the Sinic world, encompasses multiple countries in East Asia and Southeast Asia that historically were heavily influenced by Chinese culture, norms and traditions. According to academic consensus, the Sinosphere comprises four entities: Greater China, Japan, Korea, and Vietnam. Other definitions may include Mongolia and Singapore, largely due to limited historical Chinese influences or increasing modern-day Chinese diaspora. The Sinosphere is not to be confused with Sinophone, which indicates countries where a Chinese-speaking population is dominant.
Imperial China was a major regional power in Eastern Asia and had exerted influence on tributary states and neighboring states, among which were Japan, Korea, and Vietnam. These interactions brought ideological and cultural influences rooted in Confucianism, Buddhism, and Taoism. During classical history, the four cultures shared a common imperial system under respective emperors. Chinese inventions influenced, and were in turn influenced by, innovations of the other cultures in governance, philosophy, science, and the arts. Written Classical Chinese became the regional lingua franca for literary and scientific exchange, and Chinese characters (Hanzi) became locally adapted in Japan as Kanji, Korea as Hanja, and Vietnam as chแปฏ Hรกn.
In late classical history, the literary importance of classical Chinese diminished as Japan, Korea, and Vietnam each adopted their own literary device. Japan developed the Katakana and Hiragana scripts, Korea created Hangul, and Vietnam developed chแปฏ Nรดm (which is now rarely used; the modern Vietnamese alphabet is based on the Latin alphabet). Classical literature written in Chinese characters nonetheless remains an important legacy of Japanese, Korean, and Vietnamese cultures. In the 21st century, ideological and cultural influences of Confucianism and Buddhism remain visible in high culture and social doctrines.
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- "Sinosphere" | 2023-10-26 | 12 Upvotes 4 Comments