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🔗 Mathematics

The Karnaugh map (KM or K-map) is a method of simplifying Boolean algebra expressions. Maurice Karnaugh introduced it in 1953 as a refinement of Edward Veitch's 1952 Veitch chart, which actually was a rediscovery of Allan Marquand's 1881 logical diagram aka Marquand diagram but with a focus now set on its utility for switching circuits. Veitch charts are therefore also known as Marquand–Veitch diagrams, and Karnaugh maps as Karnaugh–Veitch maps (KV maps).

The Karnaugh map reduces the need for extensive calculations by taking advantage of humans' pattern-recognition capability. It also permits the rapid identification and elimination of potential race conditions.

The required Boolean results are transferred from a truth table onto a two-dimensional grid where, in Karnaugh maps, the cells are ordered in Gray code, and each cell position represents one combination of input conditions, while each cell value represents the corresponding output value. Optimal groups of 1s or 0s are identified, which represent the terms of a canonical form of the logic in the original truth table. These terms can be used to write a minimal Boolean expression representing the required logic.

Karnaugh maps are used to simplify real-world logic requirements so that they can be implemented using a minimum number of physical logic gates. A sum-of-products expression can always be implemented using AND gates feeding into an OR gate, and a product-of-sums expression leads to OR gates feeding an AND gate. Karnaugh maps can also be used to simplify logic expressions in software design. Boolean conditions, as used for example in conditional statements, can get very complicated, which makes the code difficult to read and to maintain. Once minimised, canonical sum-of-products and product-of-sums expressions can be implemented directly using AND and OR logic operators. Diagrammatic and mechanical methods for minimizing simple logic expressions have existed since at least the medieval times. More systematic methods for minimizing complex expressions began to be developed in the early 1950s, but until the mid to late 1980s the Karnaugh map was the most common used in practice.

🔗 Human rights 🔗 Medicine 🔗 Religion 🔗 Death 🔗 China 🔗 Religion/New religious movements 🔗 Religion/Falun Gong

Reports of forced organ harvesting from Falun Gong practitioners and other political prisoners in China have raised increasing concern within the international community. According to a report by former lawmaker David Kilgour, human rights campaigner David Matas and Victims of Communism Memorial Foundation researcher Ethan Gutmann, political prisoners, mainly Falun Gong practitioners, may be executed "on demand" in order to provide organs for transplant to recipients.

Reports on systematic organ harvesting from Falun Gong prisoners first emerged in 2006, though the practice is thought by some to have started six years earlier. Several researchers—most notably Matas, Kilgour and Gutmann—estimate that tens of thousands of Falun Gong prisoners of conscience have been killed to supply a lucrative trade in human organs and cadavers and that these abuses may be ongoing. These conclusions are based on a combination of statistical analysis; interviews with former prisoners, medical authorities and public security agents; and circumstantial evidence, such as the large number of Falun Gong practitioners detained extrajudicially in China and the profits to be made from selling organs.

The Chinese government long denied all accusations of organ harvesting. However, the failure of Chinese authorities to effectively address or refute the charges has drawn attention and public condemnation from some governments, international organizations and medical societies. The parliaments of Canada and the European Union, as well as the U.S. Senate and House of Representatives, have adopted resolutions condemning the forced organ harvesting from Falun Gong prisoners of conscience. United Nations Special Rapporteurs have called on the Chinese government to account for the sources of organs used in transplant practices, and the World Medical Association, the American Society of Transplantation and the Transplantation Society have called for sanctions on Chinese medical authorities. Several countries have also taken or considered measures to deter their citizens from travelling to China for the purpose of obtaining organs. A documentary on organ harvesting from Falun Gong practitioners, Human Harvest, received a 2014 Peabody Award recognizing excellence in broadcast journalism. China eventually admitted that it had engaged in systematic organ harvesting from death row prisoners, though it denies that such an organ harvesting program is ongoing.

🔗 Italy 🔗 Food and drink 🔗 Diptera 🔗 Food and drink/Cheeses

Casu martzu (Sardinian pronunciation: [ˈkazu ˈmaɾtsu]; literally 'rotten/putrid cheese'), sometimes spelled casu marzu, and also called casu modde, casu cundídu and casu fràzigu in Sardinian language, is a traditional Sardinian sheep milk cheese that contains live insect larvae (maggots). A variation of the cheese, casgiu merzu, is also produced in some Southern Corsican villages like Sartene.

Derived from pecorino, casu martzu goes beyond typical fermentation to a stage of decomposition, brought about by the digestive action of the larvae of the cheese fly of the Piophilidae family. These larvae are deliberately introduced to the cheese, promoting an advanced level of fermentation and breaking down of the cheese's fats. The texture of the cheese becomes very soft, with some liquid (called làgrima, Sardinian for "teardrop") seeping out. The larvae themselves appear as translucent white worms, roughly 8 mm (0.3 in) long.

🔗 Plants 🔗 Forestry 🔗 Ecology

Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate disrupted biodiverse steady-state ecosystems as part of ecological succession. A number of kinds of events can create good conditions for pioneers, including disruption by natural disasters, such as wildfire, flood, mudslide, lava flow or a climate-related extinction event or by anthropogenic habitat destruction, such as through land clearance for agriculture or construction or industrial damage. Pioneer species play an important role in creating soil in primary succession, and stabilizing soil and nutrients in secondary succession.

For humans, because pioneer species quickly occupy disrupted spaces they are sometimes treated as weeds or nuisance wildlife, such as the common dandelion or stinging nettle. Even though humans have mixed relationships with these plants, these species tend to help improve the ecosystem because they can break up compacted soils and accumulate nutrients that help with a transition back to a more mature ecosystem. In human managed ecological restoration or agroforestry, trees and herbaceous pioneers can be used to restore soil qualities and provide shelter for slower growing or more demanding plants. Some systems use introduced species to restore the ecosystem, or for environmental remediation. The durability of pioneer species can also make them potential invasive species.

🔗 Statistics

Extreme learning machines are feedforward neural networks for classification, regression, clustering, sparse approximation, compression and feature learning with a single layer or multiple layers of hidden nodes, where the parameters of hidden nodes (not just the weights connecting inputs to hidden nodes) need not be tuned. These hidden nodes can be randomly assigned and never updated (i.e. they are random projection but with nonlinear transforms), or can be inherited from their ancestors without being changed. In most cases, the output weights of hidden nodes are usually learned in a single step, which essentially amounts to learning a linear model. The name "extreme learning machine" (ELM) was given to such models by its main inventor Guang-Bin Huang.

According to their creators, these models are able to produce good generalization performance and learn thousands of times faster than networks trained using backpropagation. In literature, it also shows that these models can outperform support vector machines (SVM) and SVM provides suboptimal solutions in both classification and regression applications.

The MU puzzle is a puzzle stated by Douglas Hofstadter and found in Gödel, Escher, Bach involving a simple formal system called "MIU". Hofstadter's motivation is to contrast reasoning within a formal system (ie., deriving theorems) against reasoning about the formal system itself. MIU is an example of a Post canonical system and can be reformulated as a string rewriting system.

🔗 Politics 🔗 Anti-war 🔗 Globalization

Global Peace Index (GPI) measures the relative position of nations' and regions' peacefulness. The GPI ranks 172 independent states and territories (99.7 percent of the world's population) according to their levels of peacefulness. In the past decade, the GPI has presented trends of increased global violence and less peacefulness. It also increases the world peace program in the world.

The GPI is a report produced by the Institute for Economics & Peace (IEP) and developed in consultation with an international panel of peace experts from peace institutes and think tanks with data collected and collated by the Economist Intelligence Unit. The Index was first launched in May 2009, with subsequent reports being released annually. In 2015 it ranked 165 countries, up from 121 in 2007. The study was conceived by Australian technology entrepreneur Steve Killelea, and is endorsed by individuals such as former UN Secretary-General Kofi Annan, the Dalai Lama, archbishop Desmond Tutu, former President of Finland and 2008 Nobel Peace Prize laureate Martti Ahtisaari, Nobel laureate Muhammad Yunus, economist Jeffrey Sachs, former president of Ireland Mary Robinson, former Deputy Secretary-General of the United Nations Jan Eliasson and former United States president Jimmy Carter. The updated index is released each year at events in London, Washington, DC; and at the United Nations Secretariat in New York.

The 2019 GPI indicates Iceland, New Zealand, Portugal, Austria and Denmark to be the most peaceful countries and Somalia, Afghanistan, Syria, South Sudan, Yemen, and Iraq to be the least peaceful. Long-term findings of the 2017 GPI include a less peaceful world over the past decade, a 2.14 per cent deterioration in the global level of peace in the past decade, growing inequality in peace between the most and least peaceful countries, a long-term reduction in the GPI Militarization domain, and a widening impact of terrorism, with historically high numbers of people killed in terrorist incidents over the past 10 years.

🔗 Computing 🔗 Computing/Computer hardware

N8VEM was a homebrew computing project. It featured a variety of free and open hardware and software. N8VEM builders made their own homebrew computer systems for themselves and shared their experiences with other homebrew computer hobbyists. N8VEM homebrew computer components are made in the style of vintage computers of the mid to late 1970s and early 1980s using a mix of classic and modern technologies. They are designed with ease of amateur assembly in mind.

In November 2015 the N8VEM project was ended by its creator Andrew Lynch and the community reconvened under the new name of Retrobrew Computers.

🔗 Military history 🔗 Politics 🔗 Politics of the United Kingdom 🔗 Military history/European military history 🔗 Military history/British military history

The letters of last resort are four identically worded handwritten letters from the Prime Minister of the United Kingdom to the commanding officers of the four British ballistic missile submarines. They contain orders on what action to take in the event that an enemy nuclear strike has destroyed the British government and has killed or otherwise incapacitated both the prime minister and the "second person" (normally a high-ranking member of the Cabinet) whom the prime minister has designated to make a decision on how to act in the event of the prime minister's death. In the event that the orders are carried out, the action taken could be the last official act of Government of the United Kingdom.

The letters are stored inside two nested safes in the control room of each submarine. The letters are destroyed unopened after a prime minister leaves office, so their content remains known only to the prime minister who issued them.