Lobster

Clawed lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans.

They have long bodies with muscular tails, and live in crevices or burrows on the sea floor. Three of their five pairs of legs have claws, including the first pair, which are usually much larger than the others. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate. Commercially important species include two species of Homarus from the northern Atlantic Ocean, and scampi – the Northern Hemisphere genus Nephrops and the Southern Hemisphere genus Metanephrops. Although several other groups of crustaceans have the word "lobster" in their names, the unqualified term "lobster" generally refers to the clawed lobsters of the family Nephropidae. Clawed lobsters are not closely related to spiny lobsters or slipper lobsters, which have no claws (chelae), or to squat lobsters. The closest living relatives of clawed lobsters are the reef lobsters and the three families of freshwater crayfish.

Lobster (magazine)

Lobster is a magazine that is interested primarily in the influence of intelligence and security services on politics and world trade, what it calls deep politics or parapolitics. It combines the examination of conspiracy theories and contemporary history.Lobster is edited and published in the United Kingdom and has appeared twice a year for 32 years, at first in 16-page A5 format, then as an A4 magazine. Operating on a shoestring, its distinguished contributors include academics and others. Since 2009 it is distributed as a free downloadable PDF document.

According to the Hull Daily Mail, Lobster 'investigates government conspiracies, state espionage and the secret service.' In 1986 the magazine scooped mainstream media by uncovering the secret Clockwork Orange operation, implicated in trying to destabilise the British government. Colin Wallace, a former Northern Ireland army intelligence officer described how he had been instructed to smear leading UK politicians. Questions were asked in the House of Commons and an extended scandal ensued.

Lobster (novel)

Lobster is a novella written by Guillaume Lecasble, translated by Poly McLean and published in the UK by Dedalus Books in 2005.

Reception

The novel received positive reviews in the press. Nicholas Lezard, in The Guardian, enjoyed Lobster, concluding "There was a Lobster-shaped hole in world literature which has now been neatly filled by this remarkable work.".

In The Daily Telegraph, Sam Leith recommended it in a list of 'Mad Stuff'.

In Kirkus Reviews, the novel received a positive review which recommended it as a "brief, bizarre, boiling broth of surrealism, romantic fatalism and slapstick."

Publisher's Weekly also enjoyed the novel, calling it "both tender and appalling".

References

Links

Crab

Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) (Greek: βραχύς / brachys = short,οὐρά / οura = tail), usually entirely hidden under the thorax. They live in all the world's oceans, in fresh water, and on land, are generally covered with a thick exoskeleton and have a single pair of claws. Many other animals with similar names – such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs and crab lice – are not true crabs.

Evolution

Crabs are generally covered with a thick exoskeleton, composed primarily of calcium carbonate, and armed with a single pair of chelae (claws). Crabs are found in all of the world's oceans, while many crabs live in fresh water and on land, particularly in tropical regions. Crabs vary in size from the pea crab, a few millimetres wide, to the Japanese spider crab, with a leg span of up to 4 metres (13 ft).

About 850 species of crab are freshwater, terrestrial or semi-terrestrial species; they are found throughout the world's tropical and semi-tropical regions. They were previously thought to be a monophyletic group, but are now believed to represent at least two distinct lineages, one in the Old World and one in the New World.

Crab (unit)

A Crab is a standard astrophotometrical unit for measurement of the intensity of Astrophysical X-ray sources. One Crab is defined as the intensity of the Crab Nebula at the corresponding X-ray photon energy.

The Crab Nebula, and the Crab Pulsar within it, is an intense space X-ray source. It is used as a standard candle in the calibration procedure of X-ray instruments in space. However, because of the Crab Nebula's variable intensity at different X-ray energies, conversion of the Crab to another units depends on the X-ray energy range of interest.

In the photon energy range from 2 to 10 keV, 1 Crab equals 2.4 · 10⁻⁸erg cm⁻²s⁻¹ = 15 keV cm⁻² s⁻¹ = 2.4 · 10⁻¹¹W m⁻². For energies greater than ~30 keV, the Crab Nebula becomes unsuitable for calibration purposes, as its flux can no longer be characterized by a single coherent model.

The unit mCrab, or milliCrab, is sometimes used instead of the Crab.

References

Crab (cipher)

In cryptography, Crab is a block cipher proposed by Burt Kaliski and Matt Robshaw at the first Fast Software Encryption workshop in 1993. Not really intended for use, Crab was developed to demonstrate how ideas from hash functions could be used to create a fast cipher.

Crab has an unusually large block size of 8192 bits. Its creators suggested using an 80-bit key, but the cipher could use any key size. The authors didn't specify an actual key schedule, only that the key is used to generate two large sets of subkeys: a permutation of the numbers 0 through 255, and an array of 2048 32-bit numbers. The block is divided into 256 32-bit subblocks, which are permuted at the beginning. Then the algorithm makes four passes over the data, each time applying one of four transformations adapted from MD5.

A brief note on the cryptanalysis of Crab is included in Markku-Juhani Saarinen's paper on block ciphers based on SHA-1 and MD5, published at FSE 2003. The author demonstrates a weakness in Crab that permits a distinguisher using no more than a dozen chosen plaintexts, and speculates that this can be converted into a full key-recovery attack using no more than 2¹⁶ chosen plaintexts. Such an attack would depend on the key schedule used.