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๐Ÿ”— Vinฤa symbols

๐Ÿ”— Writing systems ๐Ÿ”— Archaeology ๐Ÿ”— Romania

The Vinฤa symbols, sometimes known as the Danube script, Vinฤa signs, Vinฤa script, Vinฤaโ€“Turdaศ™ script, Old European script, etc., are a set of symbols found on Neolithic era (6th to 5th millennia BC) artifacts from the Vinฤa culture of Central Europe and Southeastern Europe. The vast majority of historians agree that those symbols are not a writing system, but private symbols or ornaments of some kind. A minority of historians claim that this is the earliest known writing system that has influenced other early writing systems.

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๐Ÿ”— Differential Power Analysis

๐Ÿ”— Cryptography ๐Ÿ”— Cryptography/Computer science

In cryptography, power analysis is a form of side channel attack in which the attacker studies the power consumption of a cryptographic hardware device (such as a smart card, tamper-resistant "black box", or integrated circuit). The attack can non-invasively extract cryptographic keys and other secret information from the device.

Simple power analysis (SPA) involves visually interpreting power traces, or graphs of electrical activity over time. Differential power analysis (DPA) is a more advanced form of power analysis, which can allow an attacker to compute the intermediate values within cryptographic computations through statistical analysis of data collected from multiple cryptographic operations. SPA and DPA were introduced to the open cryptology community in 1998 by Paul Kocher, Joshua Jaffe and Benjamin Jun.

๐Ÿ”— Third Normal Form

๐Ÿ”— Databases

Third normal form (3NF) is a database schema design approach for relational databases which uses normalizing principles to reduce the duplication of data, avoid data anomalies, ensure referential integrity, and simplify data management. It was defined in 1971 by Edgar F. Codd, an English computer scientist who invented the relational model for database management.

A database relation (e.g. a database table) is said to meet third normal form standards if all the attributes (e.g. database columns) are functionally dependent on solely the primary key. Codd defined this as a relation in second normal form where all non-prime attributes depend only on the candidate keys and do not have a transitive dependency on another key.

A hypothetical example of a failure to meet third normal form would be a hospital database having a table of patients which included a column for the telephone number of their doctor. The phone number is dependent on the doctor, rather than the patient, thus would be better stored in a table of doctors. The negative outcome of such a design is that a doctor's number will be duplicated in the database if they have multiple patients, thus increasing both the chance of input error and the cost and risk of updating that number should it change (compared to a third normal form-compliant data model that only stores a doctor's number once on a doctor table).

Codd later realized that 3NF did not eliminate all undesirable data anomalies and developed a stronger version to address this in 1974, known as Boyceโ€“Codd normal form.

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๐Ÿ”— Marsh Chapel Experiment

๐Ÿ”— Psychoactive and Recreational Drugs

The Marsh Chapel Experiment, also called the "Good Friday Experiment", was a 1962 experiment conducted on Good Friday at Boston University's Marsh Chapel. Walter N. Pahnke, a graduate student in theology at Harvard Divinity School, designed the experiment under the supervision of Timothy Leary, Richard Alpert, and the Harvard Psilocybin Project. Pahnke's experiment investigated whether psilocybin (the active principle in psilocybin mushrooms) would act as a reliable entheogen in religiously predisposed subjects.

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๐Ÿ”— Diego Garcia

๐Ÿ”— United States/U.S. Government ๐Ÿ”— United States ๐Ÿ”— Aviation ๐Ÿ”— Military history ๐Ÿ”— Military history/Military aviation ๐Ÿ”— Military history/North American military history ๐Ÿ”— Military history/United States military history ๐Ÿ”— Africa ๐Ÿ”— United Kingdom ๐Ÿ”— Correction and Detention Facilities ๐Ÿ”— Military history/Maritime warfare ๐Ÿ”— Cold War ๐Ÿ”— Islands ๐Ÿ”— British Overseas Territories ๐Ÿ”— Aviation/airport ๐Ÿ”— Asia ๐Ÿ”— Asia/British Indian Ocean Territory ๐Ÿ”— Africa/Mauritius

Diego Garcia () is the largest island of the Chagos Archipelago. It has been used as a joint UKโ€“U.S. military base since the 1970s, following the expulsion of the Chagossians by the UK government. The Chagos Islands are a British overseas territory, though a treaty to transfer sovereignty from the UK to Mauritius was signed on 22 May 2025, with a provision that the military base at the island would remain under British control for at least 99 years. The agreement may be renewed for an additional 40 years after the initial 99-year period, and for an additional period thereafter. The UK government expected the treaty to be ratified sometime in 2026. The UN Committee on the Elimination of Racial Discrimination has expressed "deep concern" at the terms of the deal.

Located just south of the equator in the central Indian Ocean, Diego Garcia lies 3,535ย km (2,197ย mi) east of Tanzania, 2,984ย km (1,854ย mi) east-southeast of Somalia, 726ย km (451ย mi) south of the Maldives, 1,796ย km (1,116ย mi) southwest of India, 2,877ย km (1,788ย mi) west-southwest of Sumatra, 4,723ย km (2,935ย mi) northwest of Australia, and 2,112ย km (1,312ย mi) northeast of Mauritius Island. Diego Garcia is part of the Chagosโ€“Laccadive Ridge, an underwater mountain range that includes the Lakshadweep, the Maldives, and the other 60 small islands of the Chagos Archipelago. The island observes UTC+6 year-round.

Diego Garcia was discovered by Portuguese sailors in 1512 and remained uninhabited until the French began using it as a leper colony and for coconut plantations in the late 18th century. After the Napoleonic Wars, the island was transferred to British control. It remained part of Mauritius until 1965, when it became part of the newly formed British Indian Ocean Territory (BIOT).

In 1966, Diego Garcia had a population of 924, mostly contract workers employed in coconut plantations. However, between 1968 and 1973, the Chagossian inhabitants were forcibly removed to make way for the military base. In 2019, the International Court of Justice issued a non-binding advisory opinion that the decolonisation of Mauritius had not been lawfully completed when it gained independence in 1968, and that the UK was "under an obligation to end its administration of the Chagos Archipelago as rapidly as possible". The United Nations General Assembly later voted overwhelmingly in favour of a resolution endorsing this opinion and calling on the UK to end its administration, though the UK has dismissed the ruling as non-binding.

Until the resettlement of รŽle du Coin, Diego Garcia remained the only inhabited island of the BIOT, with a population of around 4,000 consisting predominantly of military personnel. It is one of two critical U.S. bomber bases in the Indo-Pacific region, alongside Andersen Air Force Base in Guam. It is nicknamed the "Footprint of Freedom" by the U.S. Navy due to its shape and strategic location in the Indian Ocean.

๐Ÿ”— Hy

๐Ÿ”— Computing ๐Ÿ”— Computer science ๐Ÿ”— Computing/Software

Hy (alternately, Hylang) is a programming language, a dialect of the language Lisp designed to interact with the language Python by translating expressions into Python's abstract syntax tree (AST). Hy was introduced at Python Conference (PyCon) 2013 by Paul Tagliamonte.

Similar to Kawa's and Clojure's mapping of s-expressions onto the Java virtual machine (JVM), Hy is meant to operate as a transparent Lisp front end to Python's abstract syntax. Lisp allows operating on code as data (metaprogramming). Thus, Hy can be used to write domain-specific languages. Hy also allows Python libraries, including the standard library, to be imported and accessed alongside Hy code with a compiling step converting the data structure of both into Python's AST.

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  • "Hy" | 2019-08-04 | 850 Upvotes 141 Comments
  • "Hy" | 2016-11-07 | 70 Upvotes 5 Comments

๐Ÿ”— Nematode revived after 46,000 years in Siberian permafrost

๐Ÿ”— Horticulture and Gardening ๐Ÿ”— Animals ๐Ÿ”— Sanitation

The nematodes ( NEM-ษ™-tohdz or NEEM-; Greek: ฮฮทฮผฮฑฯ„ฯŽฮดฮท; 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, 0.9โ€“3.6ย km (3,000โ€“12,000ย 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.(pโ€ฏ472)

๐Ÿ”— Wikipedia tests a new UI design

๐Ÿ”— Religion ๐Ÿ”— Biology ๐Ÿ”— History of Science ๐Ÿ”— Science ๐Ÿ”— Evolutionary biology ๐Ÿ”— Molecular Biology ๐Ÿ”— Creationism ๐Ÿ”— Tree of Life ๐Ÿ”— Molecular Biology/Genetics

Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population. The evolutionary pressures that determine whether a characteristic would be common or rare within a population constantly change, resulting in a change in heritable characteristics arising over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms and molecules.

The theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book On the Origin of Species. Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive. This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness). Thus, in successive generations members of a population are more likely to be replaced by the progenies of parents with favourable characteristics that have enabled them to survive and reproduce in their respective environments. In the early 20th century, other competing ideas of evolution such as mutationism and orthogenesis were refuted as the modern synthesis reconciled Darwinian evolution with classical genetics, which established adaptive evolution as being caused by natural selection acting on Mendelian genetic variation.

All life on Earth shares a last universal common ancestor (LUCA) that lived approximately 3.5โ€“3.8ย billion years ago. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilised multicellular organisms. Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.

Evolutionary biologists have continued to study various aspects of evolution by forming and testing hypotheses as well as constructing theories based on evidence from the field or laboratory and on data generated by the methods of mathematical and theoretical biology. Their discoveries have influenced not just the development of biology but numerous other scientific and industrial fields, including agriculture, medicine, and computer science.

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๐Ÿ”— HAL/S Syntax

๐Ÿ”— Spaceflight

HAL/S (High-order Assembly Language/Shuttle) is a real-time aerospace programming language compiler and cross-compiler for avionics applications used by NASA and associated agencies (JPL, etc.). It has been used in many U.S. space projects since 1973 and its most significant use was in the Space Shuttle program (approximately 85% of the Shuttle software is coded in HAL/S). It was designed by Intermetrics in 1972 for NASA and delivered in 1973. HAL/S is written in XPL, a dialect of PL/I. Although HAL/S is designed primarily for programming on-board computers, it is general enough to meet nearly all the needs in the production, verification, and support of aerospace and other real-time applications. According to documentation from 2005, it was being maintained by the HAL/S project of United Space Alliance.

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๐Ÿ”— New Urbanism

๐Ÿ”— History ๐Ÿ”— Architecture ๐Ÿ”— Sociology ๐Ÿ”— Urban studies and planning

New Urbanism is an urban design movement which promotes environmentally friendly habits by creating walkable neighborhoods containing a wide range of housing and job types. It arose in the United States in the early 1980s, and has gradually influenced many aspects of real estate development, urban planning, and municipal land-use strategies. New urbanism attempts to address the ills associated with urban sprawl and post-Second World War suburban development.

New Urbanism is strongly influenced by urban design practices that were prominent until the rise of the automobile prior to World War II; it encompasses ten basic principles such as traditional neighborhood design (TND) and transit-oriented development (TOD). These ideas can all be circled back to two concepts: building a sense of community and the development of ecological practices.

The organizing body for New Urbanism is the Congress for the New Urbanism, founded in 1993. Its foundational text is the Charter of the New Urbanism, which begins:

We advocate the restructuring of public policy and development practices to support the following principles: neighborhoods should be diverse in use and population; communities should be designed for the pedestrian and transit as well as the car; cities and towns should be shaped by physically defined and universally accessible public spaces and community institutions; urban places should be framed by architecture and landscape design that celebrate local history, climate, ecology, and building practice.

New Urbanists support regional planning for open space; context-appropriate architecture and planning; adequate provision of infrastructure such as sporting facilities, libraries and community centres; and the balanced development of jobs and housing. They believe their strategies can reduce traffic congestion by encouraging the population to ride bikes, walk, or take the train. They also hope that this set up will increase the supply of affordable housing and rein in suburban sprawl. The Charter of the New Urbanism also covers issues such as historic preservation, safe streets, green building, and the re-development of brownfield land. The ten Principles of Intelligent Urbanism also phrase guidelines for new urbanist approaches.

Architecturally, new urbanist developments are often accompanied by New Classical, postmodern, or vernacular styles, although that is not always the case.

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