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Related to pollex: pollex valgus

thumb

1. the first and usually shortest and thickest of the digits of the hand, composed of two short bones
2. the corresponding digit in other vertebrates
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

Thumb

(processor)
An extension to the Advanced RISC Machine architecture, announced on 06 March 1995 by Advanced RISC Machines Ltd. By identifying the critical subset of the ARM instruction set and encoding it into 16 bits, ARM has succeeded in reducing typical program size by 30-40% from ARM's already excellent code density. Since this Thumb instruction set uses less memory for program storage, cost is further reduced.

All Thumb-aware processor cores combine the capability to execute both the 32-bit ARM and the 16-bit Thumb instruction sets. Careful design of the Thumb instructions allow them to be decompressed into full ARM instructions transparently during normal instruction decoding without any performance penalty. This differs from other 32-bit processors, like the Intel 486SX, with a 16-bit data bus, which require two 16-bit memory accesses to execute every 32-bit instruction and so halve performance.

The patented Thumb decompressor has been carefully designed with only a small amount of circuitry additional to the existing instruction decoder, so chip size and thus cost do not significantly increase. Designers can easily interleave fast ARM instructions (for performance critical parts of a program) with compact Thumb code to save memory.

thumb

(jargon)
The slider or "bubble" on a window system scrollbar. So called because moving it allows you to browse through the contents of a text window in a way analogous to thumbing through a book.
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

thumb

(1) See scroll bar and thumb culture.

(2) (Thumb) An extension to the architecture of an ARM chip that provides enhanced code density. It stores a subset of 32-bit instructions as compressed 16-bit instructions and decompresses them back to 32 bits upon execution. See ARM.
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References in periodicals archive ?
(2010a), the casts of sauropod tracks are composed by triangular footprints with five digit marks (I, II and III laterally oriented) and handprints with pollex impressions.
To obtain breaking forces, claws were clamped rigidly, and a container was suspended from the tip of the pollex by a loop of 4 mm diam.
For instance, while Bohn admits to joking in class about a "rule of pollex," he says he never calls it anything but a thumb when talking with nurses or writing for physicians.
Baraitser, "Severe mental retardation and absent nails of hallux and pollex," American Journal of Medical Genetics, vol.
Another significant character that distinguishes sauropod groups is the presence/absence and the morphology of the manus digit I claw mark (pollex).
Pereopod 1 (chelipeds) elongate, manus slightly compressed and increasing in width distally; pollex slightly deflexed, swollen in basal half, with small teeth on cutting edge; dactylus slightly curved, with small proximal tooth on cutting edge; curved tips cross each other and leave a small gape when fingers are closed.
Pollex & Associates Saint Clair Shores (586) 774-8130
Here, the dactyl and pollex were torn off at the first post-operation molt.
Other derived diagnostic traits of euprimates, uncommon in other mammals, are the following (e.g., Martin, 1990; Rasmussen, 2002): postorbital bar; orbital convergence, yielding stereoscopic binocular vision; grasping hands and feet, usually with opposable hallux and pollex; flat nails instead of claws on most digits; brains larger than expected on the basis of body size (high encephalization); and a slow life-history profile.
For donor tissues, the dactyl, pollex, ischium, and merus/carpus joint of the autotomized claw were used.
The following measurements were also included: internarial distance--distance between medial borders of nares; snout length--distance from tip of snout to anterior margin of eye; orbit-jaw distance--shortest distance between deepest region below eye and margin of upper jaw; naris-jaw distance--shortest distance between naris and margin of upper jaw; choana width--maximum width of choana; femur length--distance from tip of urostyle to distal end of femur; arm length--distance from proximal end of radio-ulna to proximal base of pollex; hand length--length from proximal base of pollex to tip of third finger; interfascicular distance--shortest distance between dentigerous fascicles; and tarsal length--distance from proximal border of inner metatarsal tubercle to proximal end of tibiale.
In snapping shrimps of the family Alpheidae, the major, or snapper, claw is almost as large as the abdomen and has a hammer on the moveable dactyl that fits into a reciprocal socket on the fixed pollex [ILLUSTRATION FOR FIGURE 1A OMITTED] (Przibram, 1901).