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131.
132.
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
133.
134.
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
135.
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
136.
Carola Müller 《Revista de derecho y genoma humano》2005,(22):133-151
The legislator, in the German Federal Republic, has opted for a specific legal solution in relation to the protection of the embryo. Carola Müller, in this article, describes this regulation as well as the reasons that have led to its adoption. The article finishes with an exposition of the existing social discussion in German society and the effect that the law has had. 相似文献
137.
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
138.
Silvina J. Vilas-Ghiso Diana M. Liverman 《International Environmental Agreements: Politics, Law and Economics》2007,7(2):137-169
More than a decade after NAFTA (North American Free Trade Agreement) entered into force, the environmental effects of agricultural
trade liberalization in Mexico are still controversial, emerging, and not fully understood. This paper contributes to the
literature that aims to explore trends in input use in the agricultural sector in Mexico during the post-NAFTA period among
both commercial/industrial and traditional/rainfed farmers, and examines the influence of the national and multilateral institutional
framework on these outcomes. We decompose the post-NAFTA agricultural production data into scale, technique and composition
effects to estimate the impact that trade liberalization has had on the use of fertilizer and land use, two key agricultural
inputs for which reliable aggregate data is available. We conclude that among commercial farmers patterns of crop type specialization
and significant technological improvements have led to some declines in fertilizer use but they have been offset by growth
in fertilizer use associated with growing agricultural output. Among traditional farmers increased output and specialization
in land-intensive grain crops are contributing to an increase in land under cultivation and technological improvements show
the potential, but not yet not the strength, to counteract these effects. We analyse the environmental institutional framework
and rural development plans, observing that institutional weaknesses have, in several instances, reduced the environmental
benefit of technique and composition effects. We conclude with recommendations about how the Mexican agricultural sector might
reap the environmental benefits of international agricultural trade. 相似文献
139.
140.
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