DDT (gene)

D-dopachrome decarboxylase is an enzyme that in humans is encoded by the DDT gene.

D-dopachrome tautomerase converts D-dopachrome into 5,6-dihydroxyindole. The DDT gene is related to the macrophage migration inhibitory factor (MIF) in terms of sequence, enzyme activity, and gene structure. DDT and MIF are closely linked on chromosome 22.

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Further reading

As (Unix)

as is a generic name for an assembler on Unix. On many systems the standard or pre-installed assembler is the GNU Assembler, commonly called GAS, whose executable is simply named as. This often causes the generic as to be often mistaken for the GNU Assembler. This problem is infrequent with many other assemblers if they have unique executable names; such as the Netwide Assembler, or NASM, whose executable name is its abbreviation, nasm.

As (Roman coin)

The as (plural asses), also assarius (rendered into Greek as ἀσσάριον, assarion) was a bronze, and later copper, coin used during the Roman Republic and Roman Empire.

Republican era coinage

The Romans replaced the usage of Greek coins, first by blocks and then by disks made of bronze Aes rude. The system thus named as was introduced in ca. 280 BC as a large cast bronze coin during the Roman Republic. The following fractions of the as were also produced: the bes (2/3), semis (1/2), quincunx (5/12), triens (1/3), quadrans (1/4), sextans (1/6), uncia (1/12, also a common weight unit), and semuncia (1/24), as well as multiples of the as, the dupondius (2), sestertius (2.5), tressis (3), quadrussis (4), quinarius (5), denarius (10) and aureus (250).

After the as had been issued as a cast coin for about seventy years, and its weight had been reduced in several stages, a sextantal as was introduced (meaning that it weighed one-sixth of a pound). At about the same time a silver coin, the denarius, was also introduced. Earlier Roman silver coins had been struck on the Greek weight standards that facilitated their use in southern Italy and across the Adriatic, but all Roman coins were now on a Roman weight standard. The denarius, or 'tenner', was at first tariffed at ten asses, but about 140 B.C. it was retariffed at sixteen asses. This is said to have been a result of financing the Punic Wars.

Minute and second of arc

A minute of arc (MOA), arcminute (arcmin) or minute arc is a unit of angular measurement equal to one-sixtieth (1/60) of one degree. As one degree is 1/360 of a circle, one minute of arc is 1/21600 of a circle (or, in radians, π/10800). It is used in fields that involve very small angles, such as astronomy, optometry, ophthalmology, optics, navigation, land surveying and marksmanship.

The number of square arcminutes in a complete sphere is approximately 148,510,660 square arcminutes.

A second of arc (arcsecond, arcsec) is 1/60 of an arcminute, 1/3,600 of a degree, 1/1,296,000 of a circle, and π/648,000 (about 1/206,265) of a radian. This is approximately the angle subtended by a U.S. dime coin (18mm) at a distance of 4 kilometres (about 2.5 mi).

To express even smaller angles, standard SI prefixes can be employed; the milliarcsecond (mas), for instance, is commonly used in astronomy.

Symbols and abbreviations

The standard symbol for marking the arcminute is the prime (′) (U+2032), though a single quote (') (U+0027) is commonly used where only ASCII characters are permitted. One arcminute is thus written 1′. It is also abbreviated as arcmin or amin or, less commonly, the prime with a circumflex over it ().

Nu Serpentis

Nu Serpentis (ν Ser, ν Serpentis) is a binary star in the constellation Serpens. It is approximately 193 light years from Earth.

The primary component, Nu Serpentis A, is a white A-type main sequence dwarf with an apparent magnitude of +4.32. It is separated from Nu Serpentis B, a magnitude +8.4 companion, by 46 arcseconds.

Tau6 Serpentis

Tau⁶ Serpentis (Tau⁶ Ser, τ⁶ Serpentis, τ⁶ Ser) is a G-type giant star in the constellation of Serpens, approximately 450 light-years from the Earth. It has an apparent visual magnitude of approximately 6.000, and is a member of the Ursa Major Stream.

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Öser (surname)

Öser, Oeser may refer to:

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