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Article

Allergies

The alarmingly increasing frequency of allergies, affecting over 20% of the population in developed countries, has led to the establishment of a new branch of medicine, that of allergology, which is conceptually closely related to immunology.

Article

Applied Anthropology

Applied anthropologists use their knowledge of peoples and cultures for practical purposes. They do this framed by anthropological concepts and a methodology - ethnographic fieldwork - that portrays people in their actual circumstances.

Article

Aerodynamics

Viscosity is the ability of a flowing liquid or gas to develop internal shear stresses that resist flow. In air, viscous forces are generally small in comparison with inertia forces, a condition which leads to flow instability and turbulence.

Article

Agricultural Soil Practices

Harvesting of marketable timber, if present, constitutes the first stage and may involve individual trees or a stand. Logs may be cut, stripped and piled with tree harvesters; trees may be knocked down, lifted and moved with tree-dozers.

Article

Deep Rover

A one-man submersible capable of working 4-6 hours under water to a depth of 914 m at speeds up to 1.5 knots, Deep Rover was designed by Graham Hawkes at San Leandro, Calif, and built by Can-Dive Services Ltd of Vancouver and in Dartmouth, NS, in 1984 to work in the offshore oil industry.

Article

Magnetic Poles

The north and south magnetic poles are the locations on Earth's surface where the planet's magnetic field points straight downwards (at the north magnetic pole) and upwards (at the south magnetic pole). Conventional compasses which move on a horizontal plane are useless near the magnetic poles.

Article

Hospital

The first HÔTEL-DIEU in New France was established in 1639 by 3 sisters of Augustines de la Miséricorde de Jésus in Québec City. This hospital is still in operation.

Article

Hydrography

Data collected in the field are considerably refined and condensed. Only a representative set including all critical information, such as the least depth over shoals, appears on the published chart. Typically, there is a scale reduction of 2-4 times from the field document to the chart.

Article

AIDS

Illnesses that this infection can produce include a transient disease, developing within several months of exposure. It is characterized by rash, fever, malaise, joint pains and lymphadenopathy (swollen lymph nodes).