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Updated: Aug 9, 2026
11:29
Modified Terminal Restriction Fragment Analysis for Quantifying Telomere Length Using In-gel Hybridization
Published on: July 10, 2017
Quest for long-term solutions for old problems
Environmental Health Perspectives
|April 1, 1975
Abstract:
Examples of repercussions from well-intentioned controls are cited in connection with lead in gasoline, sulfur in fuel, high industrial stacks, reduction of atmospheric particulates. The importance of tradeoffs is emphasized, and the current energy crisis cited as an example. The danger of overemphasis of past errors is that the drive for control may be weakened.
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San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
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