air (redirected from treading on air)

air (ar) the gaseous mixture which makes up the atmosphere.

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alveolar air  see under gas.

residual air  see under volume.

tidal air  see under volume.

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air (âr)

n.

1. A colorless, odorless, tasteless, gaseous mixture, approximately 78 percent nitrogen and approximately 21 percent oxygen with lesser amounts of argon, carbon dioxide, hydrogen, neon, helium, and other gases.

2. This mixture, with varying amounts of moisture and particulate matter, enveloping Earth; the atmosphere.

3. Any of various respiratory gases. No longer in technical use.

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air,

n the invisible, odorless, gaseous mixture that makes up the earth's atmosphere.

air, ambient,

n the encircling or enveloping environment; surrounding air.

air chamber,

n See chamber, relief.

air, complemental,

n See volume, inspiratory reserve.

air, functional residual,

n See capacity, functional residual.

air, minimal,

n the volume of air in the air sacs themselves (part of the residual air).

air reserve,

n See volume, expiratory reserve.

air, residual,

n See volume, residual.

air, supplemental,

n See volume, expiratory reserve.

air syringe,

n See syringe, air.

air, tidal,

n See volume, tidal.

air turbine handpiece,

n See handpiece, air turbine.

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air

the gaseous mixture that makes up the atmosphere. See also air sacs.

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air capillaries

the minuscule vessels that connect the parabronchi in avian lungs, in which there are no blind-ended tubules.

air cell

the air-filled space between the internal and external shell membranes of a bird's egg.

air changes per hour

the standard measurements used to indicate the level of ventilation in a building especially with respect to removal of humidity, noxious gases and carbon dioxide.

air dried

said of feed that is dried in the open with only natural movement of air, e.g. conventional hay. Contains about 10% water.

air filtration

used as a means of reducing contamination inside a building, the efficiency depending on the pore size of the filter. A technique of some value when combined with temperature control in reducing the prevalence of pneumonia in calves in intensive veal producing units.

air flow rates

are important in assessing the suitability of a ventilating system in animal accommodation. Standards for suitable flow rates for different species and age groups for heating and cooling are available.

air gap technique

in radiography, a technique to reduce scatter of radiation by increasing the distance between the patient and the surface of the cassette.

air hunger

a distressing dyspnea affecting both inspiration and expiration which occurs in paroxysms; characteristic of diabetic acidosis and coma. Called also Kussmaul's respiration.

air movement

includes air changes voiding humidity and gases to the exterior plus movements within the space which facilitate cooling.

air passages

the combined air delivery system of the upper and lower respiratory tracts including nasal cavities, pharynx, laryngeal cavity, trachea, bronchi and bronchioles.

air pollution

contamination of the air with deleterious or esthetically unattractive chemical, physical or biological material. Usually reserved for pollutants generated by humans.

air pump

a small electrically driven appliance used to provide a constant stream of air bubbles to aquaria. The bubbles themselves add little oxygen to the water but the constant disturbance of the surface of the water does.

air quality

the determination of air flow rate, temperature, humidity, freedom from bacteria, solid particles, obnoxious effluvia and poisonous gases—especially hydrogen sulfide and methane from sullage pits under the animal accommodation.

air trapping

dilatation of alveoli without destruction of their walls.

air vesicles

extend radially from parabronchi in the lungs of birds and connect with air capillaries, in which gaseous exchange occurs with vascular capillaries.