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The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
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Hazardous waste management poses increasing problems for Canadian provinces and American states, given the vast quantities and types of wastes generated and the virtual inability to open new storage, treatment, or disposal facilities. The Canadian experience is very similar to the American one in many respects, except for the fact that three provinces (Alberta, Manitoba, and Quebec) have devised alternative approaches to siting that appear successful in moving beyond the political gridlock so common on this issue. In each of these cases, traditional, top-down approaches to siting have been eschewed in favor of a more comprehensive approach that includes extensive public participation, economic and social compensation packages, formal partnerships between public and private organizations, and direct links between siting proposals and other aspects of waste management, including waste reduction, recycling, and export/import control.  相似文献   
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The increased risk of child maltreatment in the presence of domestic violence is well documented, but much remains unknown about factors that modify this relationship. This study investigates the roles of risk and protective factors in the relationship between domestic violence and being reported to the Department of Social Services for child maltreatment. Consistent with the literature, we find a significant overlap between domestic violence and maltreatment. Young maternal age, low education, low income, and lack of involvement in a religious community add to the risk for maltreatment associated with domestic violence. Separation between the maternal caregiver and her partner significantly reduces the risk for maltreatment when domestic violence is reported. A significant reduction in the risk for maltreatment is also found with higher levels of support from the maternal caregiver reported by the child in the context of domestic violence.  相似文献   
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In a case of suicidal application of electricity differences between the rectal temperature of the body and the suspected time of death were observed.In order to answer the question whether an electric current from hand to hand over >30 min led to a rise in body temperature FEM-based computer simulations and animal experiments were carried out. Both resulted in a warming of the soft parts in the arm without warming the body core. Thus a temperature-based estimation of the time since death can also be used in cases with electricity as the cause of death. Besides, in the animal experiment we found a spontaneous rise in the body core temperature even without application of electricity which may be a reason for the typical temperature plateau after death.  相似文献   
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U.S. Supreme Court Justice Thurgood Marshall offered his opinion regarding the utility of public opinion polls as a tool for assessing the “evolving standards of decency” regarding capital punishment. His arguments became known as the Marshall hypotheses and spawned a considerable body of empirical testing. The three Marshall hypotheses are: (1) support for capital punishment is inversely associated with knowledge about it, (2) exposure to information about capital punishment produces sentiments in opposition to capital punishment, but (3) exposure to information about capital punishment will have no impact on those who support it for retributive reasons. The results of previous tests of these hypotheses were somewhat mixed but supportive. None of these studies, however, examined the effects of change in knowledge levels with changes, if any, in death penalty attitudes and beliefs as needed for a more complete test of the Marshall hypotheses. The present study addressed this shortcoming. The results provided mixed support for these three hypotheses. That is, death penalty supporters were somewhat less informed than death penalty opponents; exposure to death penalty information and knowledge gains tended to be associated with attitudinal change in a directions suggested by these hypotheses; but, retributivists' attitudes toward and beliefs about capital punishment were not any more resistant to change than were the attitudes and beliefs of non-retributivists.  相似文献   
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Conducting child custody evaluations is one of the most complex, challenging, and sometimes risky professional endeavors that a mental health professional can perform. This article examines the professional and personal challenges which may be encountered by the evaluator. In addition to discussing the role requirements and need to maintain awareness of bias and countertransference, challenges such as coping with state board or ethics complaints and possible risks to personal safety are also addressed. Suggestions for risk management and coping with the demands of these assessments are offered, as well as the benefits and rewards of engaging in this important work.  相似文献   
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