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
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

Block

A large piece of stone, taken from the quarry to the mill for sawing and further working.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

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

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

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.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

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
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

block

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

Compare record, sector.
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

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.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
Dangerous arrhythmias such as ventricular tachycardia and complete AV block are possibilities in patients with TCM when features of conduction tissue disease are present.
Table 1:ECG changes from day of admission to discharge Day HR/min PR interval On admission 50 Normal 6 hrs 40 Varying 10 hrs 65 0.28 sec 24 hrs 150 Progressive shortening 48 hrs 107 0.24 sec 4th day 53 0.12 sec 5th day 50 Varying 8th day 50 Varying 9th day 60 Varying 10th day 93 Varying 11th day 60 Varying 12th day 90 0.16 sec 14th day 84 0.16 sec Day ST-T wave changes Conclusion On admission No changes normal 6 hrs ST [up arrow] V2 Varying 2nd degree block type I 10 hrs ST [up arrow] V1,V2,T 1st degree AV block inversion V1, V2,V3 24 hrs ST [down arrow] & T AV dissociation,?
Comparing the complication rates of 2-5% of other centres,14,17,19 we documented a complication rate of 4%, including a single case of persistent 3rd degree AV block requiring permanent pacemaker and one mortality.
Atrial fibrillation was observed in 5 (16.66%) patients in Group A compared to 1 (3.33%) in Group B, complete AV block was observed in 5 (16.66%) patients in Group A and no patient in Group B developed complete AV block.
Prevalence of right atrial enlargement, left atrial enlargement, 1st degree AV block, IInd degree AV block and ventricular premature complexes had been observed in two dogs for each indicating 5.00 percent prevalence.
Jude 5816, atrial lead Medtronic 4076, and ventricular lead Medtronic 4074) since 2010 due to sick sinus syndrome and AV block II Mobitz type 2.
describe a case of an elderly immunocompetent male who was found to have pericardial tamponade along with third-degree AV block. However, pericardial fluid analysis did not reveal the diagnosis until a transvenous biopsy of the cardiac tumor revealed non-Hodgkin large B-cell lymphoma [7, 10].
AVB could occur during the drug therapy including [beta]-blockers and digoxin, or non-DHP CCBs might cause AV block, primarily in the AV nodal area.
Our case is unusual to begin with as our patient had a dual-chamber pacemaker implanted for sick sinus syndrome at the age of 46 years; however, he did not show any progression to AV block after 16 years which is uncommon for molecular abnormalities of ion channel/cardiac proteins which usually undergo significant evolution to bradycardia/ AV block with time.
Optimizing the AV delay in DDD pacemaker patients with high degree AV block: mitral valve Doppler versus impedance cardiography.