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121.
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
122.
Veto Players and Civil War Duration 总被引:1,自引:0,他引:1
David E. Cunningham 《American journal of political science》2006,50(4):875-892
Civil wars show a remarkable variation in how long they last. Some end within days; others continue for decades. What explains the extreme intractability of some wars while others are resolved quickly? This article argues that conflicts with multiple actors who must approve a settlement (veto players) are longer because there are fewer acceptable agreements, information asymmetries are more acute, and shifting alliances and incentives to hold out make negotiation more difficult. This veto player approach to explaining variation in civil war duration is tested using a new dataset containing monthly data on all parties to each civil war begun since World War II. The statistical analysis shows a strong correlation between the number of veto players and the duration of civil war. 相似文献
123.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported. 相似文献
124.
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
125.
Jay S. Albanese 《Trends in Organized Crime》2005,8(4):6-14
In the same way that larceny characterized much of twentieth century, fraud will likely characterize the twenty-first century.
Larceny remains the most common oi all serious crimes, but fraud may overtake larceny as the crime of choice in the future,
because of changes in our ownership, storage, and movement of property. Fraud involves purposely obtaining the property of
another through deception, and its popularity as a crime of choice is growing. Entrusting property to the custody oi others,
storing property at remote locations, and electronic movement of property are shown to be major changes in the way we treat
property and increase opportunities for theft. The connection between fraud and many of the serious crimes of the twenty-first
century are shown in the facts of recent cases. The motivation of thefl behind many frauds is also shown to be used to fund
larger criminal objectives, such as illegal immigration and terrorism.
The points of view expressed are those of the author and do not necessarily reflect the position or policies of the U.S. Department
of Justice. Dr. Albanese is chief of the International Center at NIJ on leave from his position as professor of Government
and Public Affairs at Virginia Commonwealth University. 相似文献
126.
The link between resource deprivation and urban violence has long been explored in criminological research. Studies, however, have largely ignored the potential for resource deprivation in particular communities to affect rates of violence in others. The relative inattention is notable because of the strong theoretical grounds to anticipate influences that extend both to geographically contiguous areas and to those that, though not contiguous, share similar social characteristics. We argue that such influences—what we term spatial and social proximity effects, respectively—constitute a central feature of community dynamics. To support this argument, we develop and test theoretically derived hypotheses about spatial and social proximity effects of resource deprivation on aggregated and disaggregated homicide counts. Our analyses indicate that local area resource deprivation contributes to violence in socially proximate communities, an effect that, in the case of instrumental homicides, is stronger when such communities are spatially proximate. We conclude by discussing the implications of our findings for theories focused on community‐level social processes and violence, and for policies aimed at reducing crime in disadvantaged areas. 相似文献
127.
Forrest S. Mosten 《Family Court Review》2007,45(1):5-11
Family lawyers are major beneficiaries of the reforms set out in the Family Law Education Reform Project (FLER) Report. This commentary from a veteran family law practitioner explores the needs of the family law bar for the training of law students in practical, interdisciplinary, client‐centered lawyering that goes beyond the traditional case method. I trace many of the current innovations evolving in family law practice and how FLER reforms will not only benefit law schools but also have a major impact in the courts and private practice sector. 相似文献
128.
Allan E. Barsky 《Family Court Review》2007,45(4):560-572
Child custody evaluators with experience in mediation may be tempted to use mediation skills and strategies in their evaluation processes. This article explores the benefits and risks of blending mediation with evaluation, comparing the perspectives of professionals and clients. 相似文献
129.
130.