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🔗 Agriculture 🔗 Plants 🔗 Forestry

Crown shyness (also canopy disengagement, canopy shyness, or intercrown spacing) is a phenomenon observed in some tree species, in which the crowns of fully stocked trees do not touch each other, forming a canopy with channel-like gaps. The phenomenon is most prevalent among trees of the same species, but also occurs between trees of different species. There exist many hypotheses as to why crown shyness is an adaptive behavior, and research suggests that it might inhibit spread of leaf-eating insect larvae.

🔗 Astronomy 🔗 Sweden 🔗 Solar System 🔗 Astronomy/Solar System

The Sweden Solar System is the world's largest permanent scale model of the Solar System. The Sun is represented by the Ericsson Globe in Stockholm, the largest hemispherical building in the world. The inner planets can also be found in Stockholm but the outer planets are situated northward in other cities along the Baltic Sea. The system was started by Nils Brenning and Gösta Gahm and is on the scale of 1:20 million.

🔗 Climate change 🔗 Environment 🔗 Science Fiction 🔗 Literature 🔗 Politics 🔗 Visual arts 🔗 Ecology 🔗 Punk music

Solarpunk is a movement that encourages optimistic envisionings of the future in light of present environmental concerns, such as climate change and pollution, as well as social inequality. Solarpunk encompasses a multitude of media such as literature, art, architecture, fashion, music, and games. Solarpunk focuses on renewable energies, as well as technology as a whole, to envision a positive future for humanity; although, it also embraces less advanced ways to reduce carbon emissions, like gardening. Solarpunk is also a genre of speculative fiction; some of the most well-known examples are Solarpunk: Ecological and Fantastical Stories in a Sustainable World and Sunvault: Stories of Solarpunk and Eco-Speculation.

🔗 California 🔗 Business 🔗 Politics 🔗 Trains 🔗 Politics/American politics 🔗 Trains/Rapid transit 🔗 Buses 🔗 Trains/Streetcars

The notion of a General Motors streetcar conspiracy emerged after General Motors (GM) and other companies were convicted of monopolizing the sale of buses and supplies to National City Lines (NCL) and its subsidiaries. In the same case, the defendants were accused of conspiring to own or control transit systems, in violation of Section 1 of the Sherman Antitrust act. The suit created lingering suspicions that the defendants had in fact plotted to dismantle streetcar systems in many cities in the United States as an attempt to monopolize surface transportation.

Between 1938 and 1950, National City Lines and its subsidiaries, American City Lines and Pacific City Lines—with investment from GM, Firestone Tire, Standard Oil of California (through a subsidiary), Federal Engineering, Phillips Petroleum, and Mack Trucks—gained control of additional transit systems in about 25 cities. Systems included St. Louis, Baltimore, Los Angeles, and Oakland. NCL often converted streetcars to bus operations in that period, although electric traction was preserved or expanded in some locations. Other systems, such as San Diego's, were converted by outgrowths of the City Lines. Most of the companies involved were convicted in 1949 of conspiracy to monopolize interstate commerce in the sale of buses, fuel, and supplies to NCL subsidiaries, but were acquitted of conspiring to monopolize the transit industry.

The story as an urban legend has been written about by Martha Bianco, Scott Bottles, Sy Adler, Jonathan Richmond, and Robert Post. It has been explored several times in print, film, and other media, notably in Who Framed Roger Rabbit, Taken for a Ride, Internal Combustion, and The End of Suburbia.

Only a handful of U.S. cities, including San Francisco, New Orleans, Newark, Cleveland, Philadelphia, Pittsburgh, and Boston, have surviving legacy rail urban transport systems based on streetcars, although their systems are significantly smaller than they once were. Other cities are re-introducing streetcars. In some cases, the streetcars do not actually ride on the street. Boston had all of its downtown lines elevated or buried by the mid-1920s, and most of the surviving lines at grade operate on their own right of way. However, San Francisco's and Philadelphia's lines do have large portions of the route that ride on the street as well as using tunnels.

🔗 Computing 🔗 Computer science 🔗 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.

🔗 Ancient Near East 🔗 Turkey 🔗 Archaeology

Göbekli Tepe (Turkish: [ɟœbecˈli teˈpe], "Potbelly Hill") is an archaeological site in the Southeastern Anatolia Region of Turkey approximately 12 km (7 mi) northeast of the city of Şanlıurfa. The tell (artificial mound) has a height of 15 m (49 ft) and is about 300 m (980 ft) in diameter. It is approximately 760 m (2,490 ft) above sea level.

The tell includes two phases of use, believed to be of a social or ritual nature by site discoverer and excavator Klaus Schmidt, dating back to the 10th–8th millennium BCE. During the first phase, belonging to the Pre-Pottery Neolithic A (PPNA), circles of massive "T-shaped" stone pillars were erected – the world's oldest known megaliths.

More than 200 pillars in about 20 circles are currently known through geophysical surveys. Each pillar has a height of up to 6 m (20 ft) and weighs up to 10 tons. They are fitted into sockets that were hewn out of the bedrock. In the second phase, belonging to the Pre-Pottery Neolithic B (PPNB), the erected pillars are smaller and stood in rectangular rooms with floors of polished lime. The site was abandoned after the Pre-Pottery Neolithic B (PPNB). Younger structures date to classical times.

The details of the structure's function remain a mystery. The excavations have been ongoing since 1996 by the German Archaeological Institute, but large parts still remain unexcavated. In 2018, the site was designated a UNESCO World Heritage Site.

🔗 Technology 🔗 Lists 🔗 Futures studies 🔗 Invention

Emerging technologies are those technical innovations that represent progressive innovations within a field for competitive advantage.

🔗 Numbers 🔗 Law

An illegal number is a number that represents information which is illegal to possess, utter, propagate, or otherwise transmit in some legal jurisdiction. Any piece of digital information is representable as a number; consequently, if communicating a specific set of information is illegal in some way, then the number may be illegal as well.

🔗 Agriculture 🔗 England 🔗 Folklore

Telling the bees is a traditional custom of many European countries in which bees would be told of important events in their keeper's lives, such as births, marriages, or departures and returns in the household. If the custom was omitted or forgotten and the bees were not "put into mourning" then it was believed a penalty would be paid, such as the bees leaving their hive, stopping the production of honey, or dying. The custom is best known in England, but has also been recorded in Ireland, Wales, Germany, Netherlands, France, Switzerland, Bohemia, and the United States.

🔗 Physics 🔗 Astronomy

The Oh-My-God particle was the highest-energy cosmic ray detected at the time (15 October 1991) by the Fly's Eye detector in Dugway Proving Ground, Utah, US. Its energy was estimated as (3.2±0.9)×10²⁰ eV, or 51 J. This is 20 million times more energetic than the highest energy measured in electromagnetic radiation emitted by an extragalactic object and 10²⁰ (100 quintillion) times the photon energy of visible light, equivalent to a 142-gram (5 oz) baseball travelling at about 26 m/s (94 km/h; 58 mph). Although higher energy cosmic rays have been detected since then, this particle's energy was unexpected, and called into question theories of that era about the origin and propagation of cosmic rays.

Assuming it was a proton, this particle traveled at 99.99999999999999999999951% of the speed of light, its Lorentz factor was 3.2×10¹¹ and its rapidity was 27.1. At this speed, if a photon were travelling with the particle, it would take over 215,000 years for the photon to gain a 1 cm lead as seen in Earth's reference frame.

The energy of this particle is some 40 million times that of the highest energy protons that have been produced in any terrestrial particle accelerator. However, only a small fraction of this energy would be available for an interaction with a proton or neutron on Earth, with most of the energy remaining in the form of kinetic energy of the products of the interaction. The effective energy available for such a collision is √2Emc², where E is the particle's energy and mc² is the mass energy of the proton. For the Oh-My-God particle, this gives 7.5×10¹⁴ eV, roughly 60 times the collision energy of the Large Hadron Collider.

While the particle's energy was higher than anything achieved in terrestrial accelerators, it was still about 40 million times lower than the Planck energy. Particles of such energy would be required in order to explore the Planck scale. A proton with that much energy would travel 1.665×10¹⁵ times closer to the speed of light than the Oh-My-God particle. As viewed from Earth it would take about 3.579×10²⁰ years, or 2.59×10¹⁰ times the current age of the universe, for a photon to gain a 1 cm lead over a Planck energy proton as observed in Earth's reference frame.

Since the first observation, at least 72 similar (energy > 5.7×10¹⁹ eV) events have been recorded, confirming the phenomenon. These ultra-high-energy cosmic ray particles are very rare; the energy of most cosmic ray particles is between 10 MeV and 10 GeV. More recent studies using the Telescope Array have suggested a source for the particles within a 20-degree radius "warm spot" in the direction of the constellation Ursa Major.