Numerical proportion considered to be an aesthetic ideal in classical design. It refers to the ratio of the base to the height of a rectangle or to the division of a line segment into two in such a way that the ratio of the shorter part to the longer is equal to that of the longer to the whole. It works out to about 1.61803:1. A rectangle constructed from golden sections (segments in this ratio) is called a golden rectangle.
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In nuclear physics, a measure of the probability that a given atomic nucleus will exhibit a specific reaction (absorption, scattering, or nuclear fission) in relation to a particular incident particle. Cross section is expressed in terms of area, and its value is chosen so that, if the bombarding particle hits a circular target of this size perpendicular to its path and centred at the nucleus, the given reaction occurs. If it misses the area, the reaction does not occur. The unit of cross section is the barn, which equals 10−24 sq cm. Cross-section values for a given nucleus depend on the energy of the bombarding particle and the kind of reaction and are often different from the actual cross-sectional area of the nucleus.
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Any two-dimensional curve traced by the intersection of a right circular cone with a plane. If the plane is perpendicular to the cone's axis, the resulting curve is a circle. Intersections at other angles result in ellipses, parabolas, and hyperbolas. The conic sections are studied in Euclidean geometry to analyze their physical properties and in analytic geometry to derive their equations. In either context, they have useful applications to optics, antenna design, structural engineering, and architecture.
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Surgical removal of a fetus from the uterus through an abdominal incision at or before full term. It is usually performed when vaginal delivery would endanger the life or health of the mother or the child. Vaginal delivery is often possible in subsequent pregnancies. Cesarean section carries the usual risks of major surgery. Once overused, largely for fear of malpractice suits, its use has been greatly reduced by the natural childbirth movement.
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There were 321 households out of which 27.7% had children under the age of 18 living with them, 56.1% were married couples living together, 12.1% had a female householder with no husband present, and 28.7% were non-families. 25.9% of all households were made up of individuals and 14.0% had someone living alone who was 65 years of age or older. The average household size was 2.40 and the average family size was 2.88.
In the town the population was spread out with 21.2% under the age of 18, 8.5% from 18 to 24, 24.3% from 25 to 44, 30.9% from 45 to 64, and 15.1% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 84.9 males. For every 100 females age 18 and over, there were 82.5 males.
The median income for a household in the town was $31,500, and the median income for a family was $37,115. Males had a median income of $29,205 versus $20,781 for females. The per capita income for the town was $17,036. About 15.0% of families and 16.3% of the population were below the poverty line, including 25.5% of those under age 18 and 12.4% of those age 65 or over.