jet stream

Any of several long, narrow, high-speed air currents that flow eastward in a generally horizontal zone in the stratosphere or upper troposphere. Jet streams are characterized by wind motions that generate strong vertical shearing action, considered largely responsible for the clear-air turbulence experienced by aircraft. They also have an effect on weather patterns. Jet streams circle the Earth in meandering paths, shifting position as well as speed with the seasons. In the winter they are nearer the Equator and their speeds are higher than in the summer. There are often two, sometimes three, jet-stream systems in each hemisphere.

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Desynchronization of biological rhythms after moving from one time zone to another. Symptoms include fatigue, loss of concentration, sleep disturbances, malaise, sluggishness, disorientation, gastrointestinal upset, and loss of appetite. Jet lag reflects an interruption of normal light and dark cycles, which influence secretion of the hormone melatonin. Melatonin plays an important role in regulating the circadian rhythm of sleep and wakefulness; because melatonin secretion occurs in response to light-dark cycles, carefully timed exposure to small amounts of light can have a dramatic effect in alleviating jet lag. In addition, melatonin supplements can be used to accelerate the resynchronization of the body clock to a new time zone. Duration and severity of jet lag depend on how much distance is covered in how little time. Travel by jet, after which the phenomenon may persist for some days, first brought the condition to notice, accounting for the name.

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Any of a class of internal-combustion engines that propel aircraft by means of the rearward discharge of a jet of fluid, usually hot exhaust gases generated by burning fuel with air drawn in from the atmosphere. Jets rely on the third of Newton's laws of motion (action and reaction are equal and opposite). The first jet-powered airplane was introduced in 1939 in Germany. The jet engine, consisting of a gas-turbine system, significantly simplified propulsion and enabled substantial increases in aircraft speed, size, and operating altitudes. Modern types of jet engines include turbojets, turbofans, turboprops, turboshafts, and ramjets. See airplane. Seealso drag; gasoline engine; lift.

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Jet is a town in Alfalfa County, Oklahoma, United States. The population was 230 at the 2000 census.

Geography

Jet is located at (36.666790, -98.181053).

According to the United States Census Bureau, the town has a total area of 0.3 square miles (0.8 km²), all of it land.

Jet is located at the intersection of U.S. Highway 64 and State Highway 38. This intersection is the southern terminus of SH-38.

Demographics

As of the census of 2000, there were 230 people, 115 households, and 71 families residing in the town. The population density was 746.3 people per square mile (286.5/km²). There were 149 housing units at an average density of 483.5/sq mi (185.6/km²). The racial makeup of the town was 96.09% White, 1.30% Native American, 0.43% Asian, and 2.17% from two or more races. Hispanic or Latino of any race were 0.43% of the population.

There were 115 households out of which 18.3% had children under the age of 18 living with them, 55.7% were married couples living together, 4.3% had a female householder with no husband present, and 37.4% were non-families. 35.7% of all households were made up of individuals and 24.3% had someone living alone who was 65 years of age or older. The average household size was 2.00 and the average family size was 2.57.

In the town the population was spread out with 16.5% under the age of 18, 3.0% from 18 to 24, 24.3% from 25 to 44, 26.1% from 45 to 64, and 30.0% who were 65 years of age or older. The median age was 50 years. For every 100 females there were 96.6 males. For every 100 females age 18 and over, there were 95.9 males.

The median income for a household in the town was $28,393, and the median income for a family was $31,250. Males had a median income of $25,000 versus $18,250 for females. The per capita income for the town was $15,024. About 2.7% of families and 5.3% of the population were below the poverty line, including none of those under the age of eighteen and 9.0% of those sixty five or over.

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