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🔗 Computer science 🔗 Databases 🔗 Databases/Computer science

R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons. The R-tree was proposed by Antonin Guttman in 1984 and has found significant use in both theoretical and applied contexts. A common real-world usage for an R-tree might be to store spatial objects such as restaurant locations or the polygons that typical maps are made of: streets, buildings, outlines of lakes, coastlines, etc. and then find answers quickly to queries such as "Find all museums within 2 km of my current location", "retrieve all road segments within 2 km of my location" (to display them in a navigation system) or "find the nearest gas station" (although not taking roads into account). The R-tree can also accelerate nearest neighbor search for various distance metrics, including great-circle distance.

🔗 Lists

The car crash song emerged as a popular pop and rock music teenage tragedy song during the 1950s and 1960s at a time when the number of people being killed in vehicle collisions was rising rapidly in many countries. In the United Kingdom, the number of fatalities on UK roads rose to a peace-time peak of 7,985 in 1966 before then falling to a new low of 2,222 in 2009. The theme also appears in country and other music styles.

🔗 Physics 🔗 Elements 🔗 Elements/Isotope 🔗 Chemistry

In nuclear physics, the island of stability is a predicted set of isotopes of superheavy elements that may have considerably longer half-lives than known isotopes of these elements. It is predicted to appear as an "island" in the chart of nuclides, separated from known stable and long-lived primordial radionuclides. Its theoretical existence is attributed to stabilizing effects of predicted "magic numbers" of protons and neutrons in the superheavy mass region.

Several predictions have been made regarding the exact location of the island of stability, though it is generally thought to center near copernicium and flerovium isotopes in the vicinity of the predicted closed neutron shell at N = 184. These models strongly suggest that the closed shell will confer further stability towards fission and alpha decay. While these effects are expected to be greatest near atomic number Z = 114 and N = 184, the region of increased stability is expected to encompass several neighboring elements, and there may also be additional islands of stability around heavier nuclei that are doubly magic (having magic numbers of both protons and neutrons). Estimates of the stability of the elements on the island are usually around a half-life of minutes or days; some estimates predict half-lives of millions of years.

Although the nuclear shell model predicting magic numbers has existed since the 1940s, the existence of long-lived superheavy nuclides has not been definitively demonstrated. Like the rest of the superheavy elements, the nuclides on the island of stability have never been found in nature; thus, they must be created artificially in a nuclear reaction to be studied. Scientists have not found a way to carry out such a reaction, for it is likely that new types of reactions will be needed to populate nuclei near the center of the island. Nevertheless, the successful synthesis of superheavy elements up to Z = 118 (oganesson) with up to 177 neutrons demonstrates a slight stabilizing effect around elements 110 to 114 that may continue in unknown isotopes, supporting the existence of the island of stability.

🔗 Environment 🔗 Death 🔗 Agriculture 🔗 Mammals 🔗 Agriculture/Livestock

A Judas goat is a trained goat used in general animal herding. The Judas goat is trained to associate with sheep or cattle, leading them to a specific destination. In stockyards, a Judas goat will lead sheep to slaughter, while its own life is spared. Judas goats are also used to lead other animals to specific pens and onto trucks. They have fallen out of use in recent times, but can still be found in various smaller slaughterhouses in some parts of the world, as well as conservation projects.

Cattle herders may use a Judas steer to serve the same purpose as a Judas goat. The technique, and the term, originated from cattle drives in the United States in the 1800s.

The term is a reference to Judas Iscariot, an apostle of Jesus Christ who betrayed Jesus in the Bible.

🔗 Biography 🔗 California 🔗 Video games 🔗 Women 🔗 Biography/sports and games 🔗 California/Southern California 🔗 California/Los Angeles area 🔗 LGBTQ+ studies 🔗 Video games/esports 🔗 LGBTQ+ studies/LGBTQ+ Person

Rebecca Ann Heineman (October 30, 1963 – November 17, 2025) was an American video game designer and programmer. Heineman was a founder or co-founder of video game companies Interplay Productions, Logicware, Contraband Entertainment, and Olde Sküül. She was the chief executive officer of Olde Sküül from 2013 until her death in 2025.

🔗 United States 🔗 Law 🔗 United States/Texas - Austin

Steve Jackson Games, Inc. v. United States Secret Service, 816 F. Supp. 432 (W.D. Tex. 1993), was a lawsuit arising from a 1990 raid by the United States Secret Service on the headquarters of Steve Jackson Games (SJG) in Austin, Texas. The raid, along with the Secret Service's unrelated Operation Sundevil, was influential in the founding of the Electronic Frontier Foundation.

🔗 United States 🔗 Aviation 🔗 Aviation/aircraft

Ballistic Recovery Systems, Inc. (commonly referred to as BRS Aerospace, or simply BRS) is a manufacturer of aircraft ballistic parachutes.

The company was formed in 1980 by Boris Popov of Saint Paul, Minnesota, after he survived a 400-foot (120 m) fall in a partially collapsed hang glider in 1975. As a result, Popov invented a parachute system that could lower an entire light aircraft to the ground in the event of loss of control, failure of the aircraft structure, or other in-flight emergencies.

Popov was granted a U.S. patent on 26 August 1986 for the so-called Ballistic Recovery System (BRS) - patent US 4607814 A.

The company has two divisions: BRS Aviation and BRS Defense.

Mithridatism is the practice of protecting oneself against a poison by gradually self-administering non-lethal amounts. The word is derived from Mithridates VI, the King of Pontus, who so feared being poisoned that he regularly ingested small doses, aiming to develop immunity.

🔗 Business

"Think" (stylized as THINK) is a slogan associated with the American multinational technology company IBM.

🔗 Philosophy 🔗 Color

Grue and bleen are examples of logical predicates coined by Nelson Goodman in Fact, Fiction, and Forecast to illustrate the "new riddle of induction" – a successor to Hume's original problem. These predicates are unusual because their application is time-dependent; many have tried to solve the new riddle on those terms, but Hilary Putnam and others have argued such time-dependency depends on the language adopted, and in some languages it is equally true for natural-sounding predicates such as "green." For Goodman they illustrate the problem of projectible predicates and ultimately, which empirical generalizations are law-like and which are not. Goodman's construction and use of grue and bleen illustrates how philosophers use simple examples in conceptual analysis.