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A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers.  相似文献   
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An improved method has been developed for the reliable classification of different C1R genetic variant forms from human serum or plasma. The method combines the use of neuraminidase-digested samples followed by monodimensional isoelectric focusing in the pH range 5 to 8 followed by immunoblotting. The method yields a simple pattern, with one major band in homozygote and two major bands in heterozygote cases.  相似文献   
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Federal transportation officials assert that labor protections in the Urban Mass Transportation Act inhibit the propensity of local transit agencies to contract with private firms for services. The authors present results from a survey of a large sample of transit managers and econometric analysis to support their conclusion that labor protections do not appear to reduce the incidence of contracting. The labor protections, however, may be costly to transit management in other ways. The authors recommend actions, aside from repeal of labor protections, to increase contracting by local transit agencies.  相似文献   
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While it is becoming increasingly evident that the post-Leninist state is experiencing a considerable decline in capacity and strength, Western analysts have been slow to address the situation analytically. This essay examines the reasons for the lack of attention paid to the state by former Sovietologists, and offers a new theoretical perspective on the Leninist and post-Leninist states. The utility of this perspective is subsequently demonstrated by applying it to the case of local government reform in Poland. The inability of the Polish reform to overcome the administrative weakness of the state demonstrates both the seriousness of the problem, and the need for greater “state” consciousness on the part of post-Sovietologists.  相似文献   
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Some features of early child care are more prominent in Norway than in other countries, such as emphasis on the outdoor environment. Of general relevance and interest is the form of day care provided by forest day-care centers. Three ideas form the development of these centers placed in wild areas. First, throughout history, Norwegians have had a close attachment to nature and some parents want to provide their children with outdoor experiences at an early age. Second, urging children to play outdoors characterizes the image many parents have of a happy, healthy childhood. Third, provision of day care for children has always been restricted in western countries, forcing parents to invent types of service that can become part of an ecological system that promotes healthy development.The forest day-care centers developed recently represent a supplement to the wide typology of child care in the 21st century. The article outlines the connections between these ideas in general European and western history and Norwegian history and presents debate and decisions about a question dating from the last half of the 1980s. It concludes that the forest day-care centers are perhaps only a modern form of the original kindergarten concept, which started in Europe and America as gardens for children not gardens of children.  相似文献   
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We consider the problem of drawing inferences within a legal framework when a person is a suspect for two separate offences. Although we are primarily concerned with scientific evidence the issue inevitably arises as to how that evidence interacts with other, non-scientific evidence. We show that, in this particular context, the evidence can be conveniently classified into three categories that concern, respectively: the first crime only; the second crime only; and evidence that relates to similarities between the two crimes. Two case examples are considered and we consider DNA, fibres and eyewitness evidence. These are viewed from the perspective of a prosecutor who has to decide whether or not to charge a suspect with one or both crimes. Graphical sensivity analyses are presented which have features that are not intuitively obvious.  相似文献   
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Although physical punishment has been studied for decades, there are gaps in the literature regarding frequently used form, context, and cross cultural differences. A comparison was made using 227 college students in the United States and Japan, who were presented with four scenarios and surveyed regarding attitudes toward physical punishment, perceptions of appropriate discipline methods, and past experience with physical punishment. Japanese and U.S. respondents reported similar personal experience with physical punishment (Japanese 86%, U.S. 91%). However, U.S. respondents reported a higher likelihood of being hit with an object than did Japanese respondents. For U.S. respondents, the bottom and the hand were the top two sites on the body used for physical punishment, whereas the head and the face were the top two places for the Japanese sample. Unlike U.S. respondents, type of child misbehavior was found to have an impact on Japanese respondents’ views on the appropriate discipline method.  相似文献   
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