barrier


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Related to barrier: Barrier methods

barrier

 [bar´e-er]
1. an obstruction.
2. a partition between two fluid compartments in the body.
3. a covering used to prevent contact with body fluids.
alveolar-capillary barrier (alveolocapillary barrier) see under membrane.
blood-air barrier alveolocapillary membrane.
blood-aqueous barrier the physiologic mechanism that prevents exchange of materials between the chambers of the eye and the blood.
blood-brain barrier see blood-brain barrier.
blood-gas barrier alveolocapillary membrane.
blood-testis barrier a barrier separating the blood from the seminiferous tubules, consisting of special junctional complexes between adjacent Sertoli cells near the base of the seminiferous epithelium.
barrier methods contraceptive methods such as condoms and diaphragms in which a plastic or rubber barrier blocks passage of spermatozoa through the vagina or cervix. See discussion under contraception.
placental barrier the tissue layers of the placenta which regulate the exchange of substances between the fetal and maternal circulation.

bar·ri·er

(bar'ē-er),
1. An obstacle or impediment.
2. In psychiatry, a conflictual agent that blocks behavior that could help resolve a personal struggle.
3. In psychotherapy, anything that acts as an impediment to the insight, constructive change, healing, and growth of a patient (for example, an unhealthy or primitive defense mechanism; secondary gain; conflicted ambivalence; unconscious motivation derived from residual conflict from an earlier developmental stage; stubbornness; lack of ability to detach, observe, or analyze).
[M.E., fr. O.Fr. barriere, fr. L.L. barraria]

barrier

(băr′ē-ər)
n.
1. Physiology A membrane, tissue, or mechanism that blocks the passage of certain substances.
2. Ecology A physical or biological factor that limits the migration, interbreeding, or free movement of individuals or populations.

barrier

Physiology
A physical or functional hurdle which a substance or cell must surmount or circumvent to have free access to a tissue or site in the body.

Social medicine
An impediment in access to a service or activity, defined in the context of the Americans with Disabilities Act (ADA), which may be architectural (e.g., requiring widened doors, wheelchair ramps and others) or communication-related (e.g., linguistic barrier, vision defects).

According to the ADA, the existance of barriers may require an employer to make reasonable accomodations in the form of obtaining an interpreter or braille forms (e.g., for paperwork), or by altering the physical layout of an office or work space.

barrier

Physiology A physical or functional hurdle which a substance or cell must surmount or circumvent to have free access to a tissue or site in the body. See Blood-brain barrier, Bone marrow barrier Social medicine An impediment in access to a service or activity, defined in the context of the Americans with Disabilities Act–ADA, which may be architectural–eg requiring widened doors, wheelchair ramps, and others or communication-related–eg linguistic barrier, vision defects. See Americans with Disabilities Act, Architectural barrier, Cultural barrier, Disability, Inequitable barrier, Reasonable accommodations.

bar·ri·er

(bar'ē-ĕr)
1. An obstacle or impediment.
2. psychiatry A conflictual agent that blocks behavior that could help resolve a personal struggle.
[M.E., fr. O. Fr. barriere, fr. L.L. barraria]

bar·ri·er

(bar'ē-ĕr)
An obstacle or impediment.
[M.E., fr. O. Fr. barriere, fr. L.L. barraria]
References in periodicals archive ?
The estimates will help USTR conduct comparative analyses of a barrier's effect over a range of industries, the agency said.
From a performance viewpoint, a crossing barrier design requires more length to achieve the same surface area at the barrel wall.
Liberty, MO, November 17, 2017 --(PR.com)-- Barriers are an important factor to be considered not only for the construction industry but also for window cleaning or other maintenance work where heights and risks are involved.
Wall Guardian FW-100A exceeds ASTM E2357 (Standard Test Method for Determining Air Leakage of Air Barrier Assemblies) with an air leakage rate of just 0.0004 cfm/ft2 @ 1.57 psf--100 times better than the test requirement.
* Using thin, high-barrier lidding films for ready-made trays and as top webs on thermoforming lines can eliminate the need for secondary barrier film or pouches;
Since acpo specializes in coating thin films with state-of-the-art equipment, converters will have alternative barrier films at an economical price that offer improved barrier properties without needing to make capital investments in a coating unit.
To explore the influence of the process of train passing on the sound barrier, numerous studies about impulsive wind pressure have been conducted [2-7].
The misunderstanding of the difference of this vapor barrier versus air barrier function in compact flat roofs goes back generations.
Although career barriers can be overcome, it often depends on the specific barrier and the personal characteristics of the individual (Swanson and Woitke, 1997).
Highways Agency project manager, Alan Apps, said: "This barrier replacement scheme will improve safety on the M62 .Concrete barriers reduce the RISK of vehicles involved in accidents crossing from one side of the motorway to the other and improve the safety of road users and road WORKERs.
While crash barriers have saved the lives of thousands of drivers, hitting a crash barrier is a factor in eight to 16 per cent of rider deaths, warns the IAM.