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951.
Sixteen trace elements found in 309 street heroin samples, piped water and contaminated water were determined using inductively coupled plasma-mass spectrometry. All the street heroin samples were found to contain high levels of sodium, a reflection of the use of sodium bicarbonate during heroin synthesis. Additionally, this element was also found to be one of the potential contaminants acquired from the piped water. Calcium could be derived from lime while iron, aluminum and zinc could have come from the metallic container used in the processing/cutting stage. The levels of these elements remained low in the heroin and it could be due to the dilution effects from the addition of adulterants. Statistical validation was performed with six links of related heroin samples using principal component analysis to find the best pretreatment for sample classification. It was obtained that normalization followed by fourth root showed promising results with 8% errors in the sample clustering. The technique was then applied to the case samples. Finally, the result suggested that the case samples could have originated from at least two major groups respectively showing unique elemental profiles at the street level.  相似文献   
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The zoning process is subject to steadily expanding volume and variety of demands and criticism. Some wish it, alone, to control the rate and location of growth and bemoan that often zoning is not so used. Others feel that zoning seldom has any rational basis and is applied on a case by case basis with little or no consideration of the existing or proposed capacity to serve the area with sewers, water, schools, parks and the many capital facilities which are an integral part of a community's infrastructure. A few say zoning is often decided on the basis of cronyism or bribery. More often critics say that zoning is decided on emotional issues by “mob rule” and that, in effect, many decisions exemplify democracy at its worst. The timid official yields to the most persistent voices by the developer, neighbors, or environmentalists and often ignores altogether the suggestions of the professional engineers and planners who in theory at least take an objective long-range view of urban development.  相似文献   
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The Food Standards Agency (FSA) aims to remove the longstanding conflict of interest between producers and consumers which is thought to lie at the heart of the rising number of food safety problems of recent years, to restore consumer confidence, and to protect public health. This paper sets out firstly to understand what the conflicts are, how they arise and their implications for food safety, and secondly to provide some means of evaluating the proposals for the Food Standards Agency. It does this by examining the current food safety regulatory regime as it relates to e. coli 0157, one of the problems that gave rise to the FSA and an exemplar of the problems of meat safety, and places it in its wider economic context.
The results show that the financial pressures on the food industry were such that food hygiene was largely dependent upon external regulation and enforcement. But the deficiencies in the conception, design and implementation of the Food Safety Act, which was fundamentally deregulatory and privileged producer interests, permitted the food safety problems to grow. The case also, by illustrating how the interests of big business predominate in the formulation of public policy at the expense of the public, reveals how the class nature of the state affects public policy and social relations. Without addressing these issues, the problems they give rise to will remain. While the case is based on experiences in Britain, the problem of food safety and the issues raised have an international significance.  相似文献   
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