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181.
Engstrom  Richard L. 《Publius》1986,16(4):109-122
In 1982, Section 2 of the U.S. Voting Rights Act was amendedto allow plaintiffs to prevail in voting rights litigation ifthey demonstrate that a challenged law or practice has a discriminatoryresult. One of the first applications of this new statutoryprovision invalidated a congressional districting plan for theNew Orleans metropolitan area, a plan that had divided the city'sblack population virtually in half. This article reviews boththe making and the unmaking of that plan, derisively known asthe "gerryduck." Although the judicial action invalidating thisexercise in racial cartography demonstrates the potential importanceof this new section of the VRA as a legal weapon against minorityvote dilution, the results test provides federal judges withenormous discretion, and the application of the test may thereforebe quite capricious.  相似文献   
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Fifty-three clusters of blowfly eggs of the genus Calliphora vicina were observed in the laboratory up to the hatching stage under reproducible and virtually field-like conditions. Rearing the larvae was then continued up to pupation, the larval growth in length being recorded several times a day. As the object was to study the dependence of the larvae increase in length on the temperature conditions in vitro, the substratal humidity and food supply were kept unchanged during the entire study. The temperature ranged from 6.5 degrees C to 35 degrees C, with the temperature for the individual cluster kept constant during the entire developmental process. Data on about 5500 measured larvae were statistically evaluated. The basic result established was that in the case of the blowfly of the genus Calliphora vicina in vivo, all developmental stages relevant to the entomologic determination of the time of death depend on the temperature conditions: (1) the duration of the egg stage increases with decreasing temperature; (2) the speed of larval growth is slower at lower temperatures; (3) the maximal larval length is reached earlier at higher temperatures; (4) the mean value of maximal length decreases with increasing temperature; (5) larvae under all temperature conditions decrease in size after having reached their maximal length, the decrease in length being more rapid at higher temperatures; (6) constant temperatures over 30 degrees C lead to "stunted forms" which do not pupate and die; (7) constant temperatures under approximately 16 degrees C after the peak of growth has been reached inhibit the readiness to pupate, which causes the larvae to fall into a stationary state of rest, which will be interrupted only when the temperature is raised and resumption of the metamorphosis is thus induced. To allow rapid reconstruction of the larval age in general practice, the established growth data were set out in the form of a diagram designated isomegalendiagram, which permits temperature-fluctuation-related entomologic determination of the time of death with a maximum degree of accuracy.  相似文献   
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