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991.
From a national perspective it is unclear whether the continued expansion of urban development seriously affects America's potential food production over the long run. Yet there are clearly regional biases toward conversion of farmland to urban uses and locally important changes in the appearance of the landscape at the rural—urban fringe. Urbanization also generates spillover effects causing the idling of farmland and the shifting from one type of agriculture to another.Land use controls aimed at directly addressing the use of the land may be effective in preventing some conversion of farmland to urban uses but the methods are costly and possibly very complex. Incentives to farmers to keep land in agriculture are generally too weak to be effective in retaining agricultural land in the face of strong urban pressures.This research was supported by a grant from the National Science Foundation (Research Applied to National Needs) to the Regional Science Research Institute.  相似文献   
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994.
The police claimed that drug trafficking was going on at the needle exchange run by the Vancouver Area Network of Drug Users, but they failed to provide any evidence to that effect. The police later apologized for their remarks and the exchange re-opened.  相似文献   
995.
Hayden T 《U.S. news & world report》2002,133(22):60-6, 68-9
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996.
The paper presents a case report of a serial but from the social point of view rather inconspicuous theft offender. The motivation of this perpetrator cannot be reduced to a simple money-making-intention. It seems to be of a more complex origin which offers possibilities for a psychological interpretation. On the other hand, this offender does clearly not fulfill the criteria of kleptomania. For such cases, Anglo-American literature offers a new concept named the "atypical theft offender" ATO, witch is outlined and critically discussed by the author.  相似文献   
997.
This study extends the literature on policy feedback and explores the extent to which public attitudes reflect learning from past government initiatives. We analyze the ways in which feedback mechanisms affecting public attitudes may differ from those earlier identified in the literature. We apply this general analytic framework to help explain variation in public attitudes toward private employer involvement in health care, explore possible causal pathways, and offer some preliminary empirical tests of these hypotheses. There are different levels of public support for the notion of employer obligation involving medical care, long-term care, and the treatment of substance abuse. Our evidence suggests that lessons about the performance of institutions in each of these policy domains represent the most important effect of existing policy on public attitudes. Furthermore, these differences correspond to what one would expect based on our model of policy feedback and cannot be explained by other plausible sources of policy legitimacy.  相似文献   
998.
This paper examines how many of the states have changed their respective scientific-evidence admissibility standards under the influence of the United States Supreme Court's 1993 Daubert decision. The authors offer a definition of what constitutes a Daubert state, and using this definition classify the fifty states into three categories. These are: Frye states (15 states, 10 with codified evidence rules patterned after the Federal Rules of Evidence (FRE)); Daubert states (26 states, 24 with FRE-based rules), and non-Frye/non-Daubert states (9 states, 7 with FRE-based rules). The authors discuss how the reliability requirement varies among the non-Frye states, and examine how particular types of evidence have fared in the Daubert era. Finally, the authors offer some predictions for the scientific evidence trends of the states.  相似文献   
999.
Raman spectroscopy was investigated to determine the optimal conditions, mainly laser wavelength/s, for the analysis of the commonly encountered black/grey and blue cotton fibres dyed with reactive dyes. In this first part, a single blue cotton fibre, its three dye components, and an undyed cotton fibre were analysed with five different laser wavelengths from two different Raman microprobe spectrometers. The quality of the spectra, fibre degradation and speed of acquisition were used to determine that, under the conditions used, the 785 and 830 nm lasers gave superior results. The 632.8 nm laser wavelengths provided good results with little acquisition time and no spectral degradation. Results indicate that, at least, the major dye component could be identified using Raman spectroscopy.  相似文献   
1000.
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