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πŸ”— Dark fibre

πŸ”— Telecommunications

A dark fibre or unlit fibre is an unused optical fibre, available for use in fibre-optic communication. Dark fibre may be leased from a network service provider.

Dark fibre originally referred to the potential network capacity of telecommunication infrastructure. Because the marginal cost of installing additional fibre optic cables is very low once a trench has been dug or conduit laid, a great excess of fibre was installed in the US during the telecom boom of the late 1990s and early 2000s. This excess capacity was later referred to as dark fibre following the dot-com crash of the early 2000s that briefly reduced demand for high-speed data transmission.

These unused fibre optic cables later created a new market for unique private services that could not be accommodated on lit fibre cables (i.e., cables used in traditional long-distance communication).

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πŸ”— Solar storm of 1859

πŸ”— Telecommunications πŸ”— Meteorology πŸ”— Astronomy πŸ”— Solar System

The solar storm of 1859 (also known as the Carrington Event) was a powerful geomagnetic storm during solar cycle 10 (1855–1867). A solar coronal mass ejection (CME) hit Earth's magnetosphere and induced the largest geomagnetic storm on record, September 1–2, 1859. The associated "white light flare" in the solar photosphere was observed and recorded by British astronomers Richard C. Carrington (1826–1875) and Richard Hodgson (1804–1872). The storm caused strong auroral displays and wrought havoc with telegraph systems. The now-standard unique IAU identifier for this flare is SOL1859-09-01.

A solar storm of this magnitude occurring today would cause widespread electrical disruptions, blackouts and damage due to extended outages of the electrical grid. The solar storm of 2012 was of similar magnitude, but it passed Earth's orbit without striking the planet, missing by nine days.

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πŸ”— Nutraloaf

πŸ”— United States πŸ”— Food and drink πŸ”— Correction and Detention Facilities

Nutraloaf (also known as Meal Loaf, prison loaf, disciplinary loaf, food loaf, lockup loaf, confinement loaf, seg loaf, grue or special management meal) is a food served in prisons in the United States and formerly Canada to inmates who have misbehaved; for example, assaulting prison guards or fellow prisoners. It is similar to meatloaf in texture, but has a wider variety of ingredients. Prison loaf is usually bland, perhaps even unpleasant, but prison wardens argue that nutraloaf provides enough nutrition to keep prisoners healthy without requiring utensils to be issued.

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πŸ”— Min Chiu Li

πŸ”— Biography πŸ”— Medicine πŸ”— Biography/science and academia πŸ”— Medicine/Society and Medicine

Min Chiu Li (Chinese: ζŽζ•ζ±‚; pinyin: Lǐ MǐnqiΓΊ; 1919–1980) was a Chinese-American oncologist and cancer researcher. Li was the first scientist to use chemotherapy to cure widely metastatic, malignant cancer.

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πŸ”— Exploding Cucumber

πŸ”— Plants πŸ”— Project-independent assessment

Cyclanthera brachystachya, the exploding cucumber (but not to be confused with Ecballium elaterium), in the cucurbit or gourd family (Cucurbitaceae), is a herbaceous vine usually grown for its curiosity value, but the fruit is also edible.

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πŸ”— Pax Calendar

πŸ”— Time

The Pax calendar was invented by James A. Colligan, SJ in 1930 as a perennializing reform of the annualized Gregorian calendar.

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πŸ”— Pick Operating System

πŸ”— Computing πŸ”— Computing/Software

The Pick operating system (often called just "the Pick system" or simply "Pick") is a demand-paged, multiuser, virtual memory, time-sharing computer operating system based around a unique MultiValue database. Pick is used primarily for business data processing. It is named after one of its developers, Dick Pick.

The term "Pick system" has also come to be used as the general name of all operating environments which employ this multivalued database and have some implementation of Pick/BASIC and ENGLISH/Access queries. Although Pick started on a variety of minicomputers, the system and its various implementations eventually spread to a large assortment of microcomputers, personal computers and mainframe computers.

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πŸ”— Norton's Dome

πŸ”— Mathematics πŸ”— Physics πŸ”— Philosophy

Norton's dome is a thought experiment that exhibits a non-deterministic system within the bounds of Newtonian mechanics. It was devised by John D. Norton in 2003. It is a special limiting case of a more general class of examples from 1997 due to Sanjay Bhat and Dennis Bernstein. The Norton's dome problem can be regarded as a problem in physics, mathematics, or philosophy.

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πŸ”— Fractional calculus

πŸ”— Mathematics

Fractional calculus is a branch of mathematical analysis that studies the several different possibilities of defining real number powers or complex number powers of the differentiation operator D

D f ( x ) = d d x f ( x ) , {\displaystyle Df(x)={\frac {d}{dx}}f(x)\,,}

and of the integration operator J

J f ( x ) = ∫ 0 x f ( s ) d s , {\displaystyle Jf(x)=\int _{0}^{x}f(s)\,ds\,,}

and developing a calculus for such operators generalizing the classical one.

In this context, the term powers refers to iterative application of a linear operator D to a function f, that is, repeatedly composing D with itself, as in D 2 ( f ) = ( D ∘ D ) ( f ) = D ( D ( f ) ) {\displaystyle D^{2}(f)=(D\circ D)(f)=D(D(f))} .

For example, one may ask for a meaningful interpretation of:

D = D 1 2 {\displaystyle {\sqrt {D}}=D^{\frac {1}{2}}}

as an analogue of the functional square root for the differentiation operator, that is, an expression for some linear operator that when applied twice to any function will have the same effect as differentiation. More generally, one can look at the question of defining a linear functional

D a {\displaystyle D^{a}}

for every real-number a in such a way that, when a takes an integer value n ∈ β„€, it coincides with the usual n-fold differentiation D if n > 0, and with the βˆ’nth power of J when n < 0.

One of the motivations behind the introduction and study of these sorts of extensions of the differentiation operator D is that the sets of operator powers { Da |a ∈ ℝ } defined in this way are continuous semigroups with parameter a, of which the original discrete semigroup of { Dn | n ∈ β„€ } for integer n is a denumerable subgroup: since continuous semigroups have a well developed mathematical theory, they can be applied to other branches of mathematics.

Fractional differential equations, also known as extraordinary differential equations, are a generalization of differential equations through the application of fractional calculus.

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πŸ”— Romanesco broccoli has a form naturally approximating a fractal

πŸ”— Food and drink πŸ”— Plants

Romanesco broccoli (also known as Roman cauliflower, Broccolo Romanesco, Romanesque cauliflower, or simply Romanesco) is an edible flower bud of the species Brassica oleracea. First documented in Italy in the 16th century, it is chartreuse in color, and has a form naturally approximating a fractal. When compared to a traditional cauliflower, it has a firmer texture and delicate, nutty flavor.

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