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🔗 Companies 🔗 Private Equity 🔗 Business 🔗 Songs 🔗 Websites 🔗 Websites/Computing

Amie Street was an indie online music store and social network service created in 2006 by Brown University seniors Elliott Breece, Elias Roman, and Joshua Boltuch, in Providence, Rhode Island. The site was notable for its demand-based pricing. The company was later moved to Long Island City in Queens, New York. In late 2010, the site was sold to Amazon who redirected customers to their own website.

🔗 Biography 🔗 Mathematics 🔗 Biography/science and academia 🔗 History of Science 🔗 Switzerland 🔗 Genealogy

The Bernoulli family (German pronunciation: [bɛʁˈnʊli]) of Basel was a patrician family, notable for having produced eight mathematically gifted academics who, among them, contributed substantially to the development of mathematics and physics during the early modern period.

🔗 History 🔗 Disaster management 🔗 Medicine 🔗 Viruses 🔗 Death 🔗 Globalization

The Spanish flu (also known as the 1918 flu pandemic) was an unusually deadly influenza pandemic. Lasting from January 1918 to December 1920, it infected 500 million people—about a quarter of the world's population at the time. The death toll is estimated to have been anywhere from 17 million to 50 million, and possibly as high as 100 million, making it one of the deadliest pandemics in human history.

To maintain morale, World War I censors minimized early reports of illness and mortality in Germany, the United Kingdom, France, and the United States. Papers were free to report the epidemic's effects in neutral Spain, such as the grave illness of King Alfonso XIII, and these stories created a false impression of Spain as especially hard hit. This gave rise to the pandemic's nickname, "Spanish flu". Historical and epidemiological data are inadequate to identify with certainty the pandemic's geographic origin, with varying views as to the origin.

Most influenza outbreaks disproportionately kill the very young and the very old, with a higher survival rate for those in between, but the Spanish flu pandemic resulted in a higher than expected mortality rate for young adults. Scientists offer several possible explanations for the high mortality rate of the 1918 influenza pandemic. Some analyses have shown the virus to be particularly deadly because it triggers a cytokine storm, which ravages the stronger immune system of young adults. In contrast, a 2007 analysis of medical journals from the period of the pandemic found that the viral infection was no more aggressive than previous influenza strains. Instead, malnourishment, overcrowded medical camps and hospitals, and poor hygiene promoted bacterial superinfection. This superinfection killed most of the victims, typically after a somewhat prolonged death bed.

The Spanish flu was the first of two pandemics caused by the H1N1 influenza virus; the second was the swine flu in 2009.

🔗 Time 🔗 Switzerland 🔗 Trains 🔗 Trains/Stations

The Swiss railway clock was designed in 1944 by Hans Hilfiker, a Swiss engineer and Swiss Federal Railways (SBB) employee, together with Moser-Baer, a Swiss clock manufacturer, for use by the SBB as a station clock. In 1953, Hilfiker added a red second hand in the shape of the baton used by train dispatch staff., giving the clock its current appearance.

🔗 Occupational Safety and Health

A criticality accident occurred on December 30, 1958, at the Los Alamos National Laboratory in Los Alamos, New Mexico, in the United States. It is one of 60 known criticality events that have occurred outside the controlled conditions of a nuclear reactor or test, though it was the third such event that took place in 1958 after events on June 16 at the Y-12 Plant in Oak Ridge, Tennessee, and on October 15 at the Vinča Nuclear Institute in Vinča, Yugoslavia. The accident involved plutonium compounds dissolved in liquid chemical reagents; within 35 hours, it killed chemical operator Cecil Kelley by severe radiation poisoning.

🔗 Germany

F60 is the series designation of five overburden conveyor bridges used in brown coal (lignite) opencast mining in the Lusatian coalfields in Germany. They were built by the former Volkseigener Betrieb TAKRAF in Lauchhammer and are the largest movable technical industrial machines in the world. As overburden conveyor bridges, they transport the overburden which lies over the coal seam. The cutting height is 60 m (200 ft), hence the name F60. In total, the F60 is up to 80 m (260 ft) high and 240 m (790 ft) wide; with a length of 502 m (1,647 ft), it is described as the lying Eiffel tower, making these behemoths not only the longest vehicle ever made—beating Seawise Giant, the longest ship—but the largest vehicle by physical dimensions ever made by humankind. In operating condition, it weighs 13,600 metric tons making the F60 also one of the heaviest land vehicles ever made, beaten only by Bagger 293, which is a giant bucket-wheel excavator. Nevertheless, despite its immense size, it is operated by only a crew of 14.

The first conveyor bridge was built from 1969 to 1972, being equipped with a feeder bridge in 1977. The second was built from 1972 to 1974, having been equipped with a feeder bridge during construction. The third conveyor bridge was built from 1976 to 1978, being provided with a feeder bridge in 1985. The fourth and fifth conveyor bridges were built 1986–1988 and 1988–1991 respectively.

There are still four F60s in operation in the Lusatian coalfields today: in the brown coal opencast mines in Jänschwalde (Brandenburg, near Jänschwalde Power Station), Welzow-Süd (Brandenburg, near Schwarze Pumpe Power Station), Nochten and Reichwalde (Saxony, both near Boxberg Power Station). The fifth F60, the last one built, is in Lichterfeld-Schacksdorf and is accessible to visitors.

🔗 Computing

FLOW-MATIC, originally known as B-0 (Business Language version 0), was the first English-like data processing language. It was developed for the UNIVAC I at Remington Rand under Grace Hopper from 1955 to 1959, and helped shape the development of COBOL.

🔗 Computer science

In computer science, corecursion is a type of operation that is dual to recursion. Whereas recursion works analytically, starting on data further from a base case and breaking it down into smaller data and repeating until one reaches a base case, corecursion works synthetically, starting from a base case and building it up, iteratively producing data further removed from a base case. Put simply, corecursive algorithms use the data that they themselves produce, bit by bit, as they become available, and needed, to produce further bits of data. A similar but distinct concept is generative recursion which may lack a definite "direction" inherent in corecursion and recursion.

Where recursion allows programs to operate on arbitrarily complex data, so long as they can be reduced to simple data (base cases), corecursion allows programs to produce arbitrarily complex and potentially infinite data structures, such as streams, so long as it can be produced from simple data (base cases) in a sequence of finite steps. Where recursion may not terminate, never reaching a base state, corecursion starts from a base state, and thus produces subsequent steps deterministically, though it may proceed indefinitely (and thus not terminate under strict evaluation), or it may consume more than it produces and thus become non-productive. Many functions that are traditionally analyzed as recursive can alternatively, and arguably more naturally, be interpreted as corecursive functions that are terminated at a given stage, for example recurrence relations such as the factorial.

Corecursion can produce both finite and infinite data structures as results, and may employ self-referential data structures. Corecursion is often used in conjunction with lazy evaluation, to produce only a finite subset of a potentially infinite structure (rather than trying to produce an entire infinite structure at once). Corecursion is a particularly important concept in functional programming, where corecursion and codata allow total languages to work with infinite data structures.

🔗 Computing 🔗 Software 🔗 Software/Computing

Mainline DHT is the name given to the Kademlia-based Distributed Hash Table (DHT) used by BitTorrent clients to find peers via the BitTorrent protocol. The idea of utilizing a DHT for distributed tracking was first implemented in Azureus 2.3.0.0 (now known as Vuze) in May 2005, from which it gained significant popularity. Unrelated but similarly timed BitTorrent, Inc. released their own similar DHT into their client, called Mainline DHT and thus popularized the use of distributed tracking in the BitTorrent Protocol. Measurement shows by 2013 users of Mainline DHT is from 10 million to 25 million, with a daily churn of at least 10 million.

🔗 Mathematics

The Banach–Tarski paradox is a theorem in set-theoretic geometry, which states the following: Given a solid ball in 3‑dimensional space, there exists a decomposition of the ball into a finite number of disjoint subsets, which can then be put back together in a different way to yield two identical copies of the original ball. Indeed, the reassembly process involves only moving the pieces around and rotating them without changing their shape. However, the pieces themselves are not "solids" in the usual sense, but infinite scatterings of points. The reconstruction can work with as few as five pieces.

A stronger form of the theorem implies that given any two "reasonable" solid objects (such as a small ball and a huge ball), the cut pieces of either one can be reassembled into the other. This is often stated informally as "a pea can be chopped up and reassembled into the Sun" and called the "pea and the Sun paradox".

The reason the Banach–Tarski theorem is called a paradox is that it contradicts basic geometric intuition. "Doubling the ball" by dividing it into parts and moving them around by rotations and translations, without any stretching, bending, or adding new points, seems to be impossible, since all these operations ought, intuitively speaking, to preserve the volume. The intuition that such operations preserve volumes is not mathematically absurd and it is even included in the formal definition of volumes. However, this is not applicable here because in this case it is impossible to define the volumes of the considered subsets. Reassembling them reproduces a volume, which happens to be different from the volume at the start.

Unlike most theorems in geometry, the proof of this result depends in a critical way on the choice of axioms for set theory. It can be proven using the axiom of choice, which allows for the construction of non-measurable sets, i.e., collections of points that do not have a volume in the ordinary sense, and whose construction requires an uncountable number of choices.

It was shown in 2005 that the pieces in the decomposition can be chosen in such a way that they can be moved continuously into place without running into one another.