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πŸ”— Decline in Insect Populations

πŸ”— Environment πŸ”— Insects πŸ”— Ecology

An increasing number of scientific studies are reporting substantial declines in insect populations worldwide. Most commonly, the declines involve reductions in abundance, though in some cases entire species are going extinct. The declines are far from uniform. In some localities, there have been reports of increases in overall insect population, and some types of insects appear to be increasing in abundance across the world.

Some of the insects most affected include bees, butterflies, moths, beetles, dragonflies and damselflies. Anecdotal evidence has been offered of much greater apparent abundance of insects in the 20th century; recollections of the windscreen phenomenon are an example.

Possible causes are similar to other biodiversity loss, with studies identifying: habitat destruction, including intensive agriculture; the use of pesticides (particularly insecticides); urbanization, and industrialization; introduced species; and climate change. Not all insect orders are affected in the same way; many groups are the subject of limited research, and comparative figures from earlier decades are often not available.

In response to the reported declines, increased insect related conservation measures have been launched. In 2018 the German government initiated an "Action Programme for Insect Protection", and in 2019 a group of 27 British entomologists and ecologists wrote an open letter calling on the research establishment in the UK "to enable intensive investigation of the real threat of ecological disruption caused by insect declines without delay".

πŸ”— Floral formula

πŸ”— Plants

A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information.

A floral formula is often used along with a floral diagram.

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πŸ”— Wolf 359

πŸ”— Astronomy πŸ”— Astronomy/Astronomical objects

Wolf 359 is a red dwarf star located in the constellation Leo, near the ecliptic. At a distance of approximately 7.9 light years from Earth, it has an apparent magnitude of 13.54 and can only be seen with a large telescope. Wolf 359 is one of the nearest stars to the Sun; only the Alpha Centauri system (including Proxima Centauri), Barnard's Star and the brown dwarfs Luhman 16 and WISE 0855βˆ’0714 are known to be closer. Its proximity to Earth has led to its mention in several works of fiction.

Wolf 359 is one of the faintest and lowest-mass stars known. At the light-emitting layer called the photosphere, it has a temperature of about 2,800Β K, which is low enough for chemical compounds to form and survive. The absorption lines of compounds such as water and titanium(II) oxide have been observed in the spectrum. The surface has a magnetic field that is stronger than the average magnetic field on the Sun. As a result of magnetic activity caused by convection, Wolf 359 is a flare star that can undergo sudden increases in luminosity for several minutes. These flares emit strong bursts of X-ray and gamma ray radiation that have been observed by space telescopes. Wolf 359 is a relatively young star with an age of less than a billion years. Two planetary companions are suspected but as yet no debris disks have been unmasked.

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πŸ”— Daimler Reitwagen

πŸ”— Germany πŸ”— Motorcycling

The Daimler Petroleum Reitwagen ("riding car") or Einspur ("single track") was a motor vehicle made by Gottlieb Daimler and Wilhelm Maybach in 1885. It is widely recognized as the first motorcycle. Daimler is often called "the father of the motorcycle" for this invention. Even when the three steam powered two wheelers that preceded the Reitwagen, the Michaux-Perreaux and Roper of 1867–1869, and the 1884 Copeland, are considered motorcycles, it remains nonetheless the first petrol internal combustion motorcycle, and the forerunner of all vehicles, land, sea and air, that use its overwhelmingly popular engine type.

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πŸ”— Sator Square

πŸ”— Religion πŸ”— Classical Greece and Rome πŸ”— Middle Ages πŸ”— Middle Ages/History πŸ”— Cryptography πŸ”— Cryptography/Computer science πŸ”— Latin πŸ”— Christianity πŸ”— Jewish history πŸ”— Occult πŸ”— Mysticism

The Sator Square (or Rotas Square) is a word square containing a five-word Latin palindrome. The earliest form has ROTAS as the top line, but in time the version with SATOR on the top line became dominant. It is a 5X5 square made up of five 5-letter words, thus consisting of 25 letters in total. These 25 letters are all derived from 8 Latin letters: 5 consonants (S, T, R, P, N) and 3 vowels (A, E, O).


In particular, this is a square 2D palindrome, which is when a square text admits four symmetries: identity, two diagonal reflections, and 180 degree rotation. As can be seen, the text may be read top-to-bottom, bottom-to-top, left-to-right, or right-to-left; and it may be rotated 180 degrees and still be read in all those ways.

The Sator Square is the earliest dateable 2D palindrome. It was found in the ruins of Pompeii, at Herculaneum, a city buried in the ash of Mount Vesuvius in 79 AD. It consists of a sentence written in Latin: "Sator Arepo Tenet Opera Rotas." Its translation has been the subject of speculation with no clear consensus; see below for details.

Other 2D Palindrome examples may be found carved on stone tablets or pressed into clay before being fired.

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πŸ”— Balloon Experiments with Amateur Radio

πŸ”— Aviation πŸ”— Canada πŸ”— Aviation/aircraft πŸ”— Amateur radio πŸ”— Canada/Alberta

Balloon Experiments with Amateur Radio (BEAR) is a series of Canadian-based amateur radio high-altitude balloon experiments by a group of amateur radio operators and experimenters from Sherwood Park and Edmonton, Alberta. The experiments started in the year 2000 and continued with BEAR-9 in 2012 reaching 36,010 metres (118,140Β ft).

The balloons are made of latex filled with either helium or hydrogen. All of the BEAR payloads carry a tracking system comprising a GPS receiver, an APRS encoder, and a radio transmitter module. Other experimental payload modules include an Amateur Radio crossband repeater, and a digital camera all of which is contained within an insulated foam box suspended below the balloon. A parachute recovery system is automatically deployed when the balloon bursts at altitude.

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πŸ”— Python syntax and semantics

πŸ”— Computing πŸ”— Computing/Software

The syntax of the Python programming language is the set of rules that defines how a Python program will be written and interpreted (by both the runtime system and by human readers). The Python language has many similarities to Perl, C, and Java. However, there are some definite differences between the languages.

πŸ”— PayPal Mafia

πŸ”— California πŸ”— California/San Francisco Bay Area πŸ”— Internet

The "PayPal Mafia" is a group of former PayPal employees and founders who have since founded and developed additional technology companies such as Tesla Motors, LinkedIn, Palantir Technologies, SpaceX, YouTube, Yelp, and Yammer. Most of the members attended Stanford University or University of Illinois at Urbana–Champaign at some point in their studies.

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πŸ”— Wikipedia list of algorithms

πŸ”— Computing πŸ”— Statistics πŸ”— Computational Biology

The following is a list of algorithms along with one-line descriptions for each.

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πŸ”— DBOS

DBOS is a Database-Oriented Operating System designed to simplify and improve the scalability, security and resilience of large-scale distributed applications. It started in 2020 as a joint open source project with MIT, Stanford and Carnegie Mellon University, after a brainstorm between Michael Stonebraker and Matei Zaharia on how to scale and improve scheduling and performance of millions of Apache Spark tasks.

The basic idea is to run a multi-node multi-core, transactional, highly-available distributed database, such as VoltDB, as the only application for a microkernel, and then to implement scheduling, messaging, file systems and other operating system services on top of the database.

The architectural philosophy is described by this quote from the abstract of their initial preprint:

All operating system state should be represented uniformly as database tables, and operations on this state should be made via queries from otherwise stateless tasks. This design makes it easy to scale and evolve the OS without whole-system refactoring, inspect and debug system state, upgrade components without downtime, manage decisions using machine learning, and implement sophisticated security features.

Stonebraker claims a variety of security benefits, from a "smaller, less porous attack surface", to the ability to log and analyze how the system state changes in real-time due to the transactional nature of the OS. Recovery from a severe bug or an attack can be as simple as rolling back the database to a previous state. And since the database is already distributed, the complexity of orchestration systems like Kubernetes can be avoided.

A prototype was built with competitive performance to existing systems.