block

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Related to AV block: Third degree AV block

block

2. a casing housing one or more freely rotating pulleys
3. Pathol
a. interference in the normal physiological functioning of an organ or part
b. See heart block
c. See nerve block
4. Psychol a short interruption of perceptual or thought processes
5. Computing a group of words treated as a unit of data on a tape, disk, etc
6. Athletics short for starting block
7. Cricket a mark made near the popping crease by a batsman to indicate his position in relation to the wicket

Block

A large piece of stone, taken from the quarry to the mill for sawing and further working.

Block

 

in engineering:

(1) A unit of a mechanism in the form of a wheel with a groove around its circumference over which a cable or chain is drawn. It is used to change the direction of a tractive force and to obtain a force or velocity advantage; more rarely, to transfer a torque. Depending on their function, blocks are known as guide, balance, runner, and driving (for imparting rotary motion to a shaft) pulleys. In order to achieve a large force or velocity advantage, a lifting mechanism made up of a combination of blocks (a block and tackle) is used.

(2) A subassembly of a machine, consisting of several identical parts, such as a block of cylinders in an internal combustion engine or the spindle block in a multiple-spindle machine.

(3) A stone (concrete or ceramic) of large size (appreciably larger than a brick) used in the construction of buildings and for road surfacing.

N. IA. NIBERG

block

[bläk]
(computer science)
A group of information units (such as records, words, characters, or digits) that are transported or considered as a single unit by virtue of their being stored in successive storage locations; for example, a group of logical records constituting a physical record.
The section of a computer memory or storage device that stores such a group of information units. Also known as storage block.
To combine two or more information units into a single unit.
A contiguous group of text characters that is marked for moving, copying, saving, deletion, or some other word-processing operation.
(design engineering)
A metal or wood case enclosing one or more pulleys; has a hook with which it can be attached to an object.
(mining engineering)
A division of a mine, usually bounded by workings but sometimes by survey lines or other arbitrary limits.
In quarrying, a large portion of rock that is removed from the quarry as a solid mass for further processing at a mill.
(petroleum engineering)
The subdivision of a sea area for the licensing of oil and gas exploration and production rights.
(statistics)
In experimental design, a homogeneous aggregation of items under observation, such as a group of contiguous plots of land or all animals in a litter.

block

block, 6
1. A masonry unit; a concrete block.
2. (Brit.) A walling unit which exceeds in length, width, or height the dimensions specified for a brick.
3. A solid piece of wood or other material.
4. A plank or timber which serves as bridging between joists or the like.
5. In quarrying, the large piece of stone, generally squared, that is taken from the quarry to the mill for sawing, slabbing, and further working.
6. A mechanical

block

1. <unit> A unit of data or memory, often, but not exclusively, on a magnetic disk or magnetic tape.

Compare record, sector.

block

(1) A group of disk or tape records that is stored and transferred as a single unit. On a CD, a block consists of 98 frames of 33 bytes for a total of 3,234 bytes, or 1/75th of a second. See block level.

(2) A group of bits or bytes that is transmitted or processed as a single unit.

(3) A group of text characters that has been marked for moving, copying, saving or other operation.

(4) A rectangular group of pixels that are processed as a unit.

(5) A group of program statements that are treated as a unit based on the results of a comparison.
References in periodicals archive ?
This latter point underscores that the transient changes in LV geometry that are the hallmark of TC can not explain the conduction abnormality given persisting AV block at greater than one year despite normalization of ventricular function within one week of TC diagnosis.
Asynchronous development of electrical remodeling and cardiac hypertrophy in the complete AV block dog.
11,12) A permanent pacemaker was implanted for complete AV block or sick sinus syndrome in 14% to 25% of patients by 20 years postoperation.
Exposure to 100 [micro]M BPA resulted in sustained and complete AV block (see Supplemental Material, Figure S1).
These new data add to the growing body of evidence supporting the use of BiV pacing for treating patients who have AV block and left ventricular dysfunction who are indicated under current clinical guidelines for permanent RV pacing with a pacemaker," said Anne B.
Electrocardiographic findings included QT prolongation in four patients, AV block in two patients and ST depression in one patient.
While RV pacing (via a single or dual chamber pacemaker) helps restore heart function in patients with LV block, recent studies suggest that in patients with both AV block and LV dysfunction, RV pacing may escalate the progression of heart failure.
Hyperkalaemia is associated with sinus arrest and PR interval changes, although AV block is uncommon (30,32).
A 71 year old female had implantation of permenant pacemaker 8 years ago owing to total AV block which was tended to be removed 1 year ago.
AEx increased the PR interval (PRi) from 102 to 166 ms characterizing a first-degree AV block (Fig.
Although clinical guidelines, cardiology textbooks, and major medical journals all attest that discontinuing the culprit drug will permanently reverse the AV block, new research suggests that the disorder will recur after discontinuation of the drug in most patients and likely will be even more severe the second time around.