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71.
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
72.
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
73.
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
74.
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
75.
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
76.
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
77.
Doris Layton MacKenzie David Bierie Ojmarrh Mitchell 《Journal of Experimental Criminology》2007,3(3):221-246
Two hundred thirty four adult male inmates entering prison were randomly assigned to an early release program in either a correctional boot camp or a large, traditional prison in the Maryland state correctional system. Boot camp releasees had marginally lower recidivism compared to those released from the traditional prison. A pre-test, post-test self report survey indicated the boot camp program had little impact on criminogenic characteristics except for a lowering of self control. In contrast, inmates in prison became more antisocial, lower in self control, worse in anger management, and reported more criminal tendencies by the end of their time in prison. Criminogenic attitudes and impulses were significantly associated with recidivism. The impact of the boot camp diminished to non-significance when antisocial attitudes or anger management problems were added to the models predicting recidivism. Implications for jurisdictions considering whether to operate correctional boot camps are discussed. 相似文献
78.
79.
California is now in its 11th year of mandatory child custody mediation, with a current yearly case volume statewide estimated at 65,494. This article profiles the variations in programs and mediation styles in 56 of the state's 58 Superior Courts. Two research studies provide the basis for the information on program structures, case activity, procedures, agreement formats, recommendations, facilities, security, and fees. 相似文献
80.
A new literary programme has been started in the West AfricanService of the B.B.C., and this article is a reprint of oneof the talks. The Ibo speaker was formerly in the Customs, andqualified as a barrister last November: he is also the authorof numerous poems in English, and of a novel, The Prince ofUtete. The other two are schoolmasters working as Assistantsat the School of Oriental and African Studies. For technicalreasons, the orthography is not quite complete. 相似文献