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921.
Claire E.V. French Cynthia G. Jensen Susan K. Vintiner Douglas A. Elliot Susan R. McGlashan 《Forensic Science International Supplement Series》2008,178(1):1-6
There are a number of forensic cases in which the identification of the epithelial cell type from which DNA originated would provide important probative evidence. This study aimed to develop a technique using histological staining of fixed cells to distinguish between skin, buccal and vaginal epithelium. First, 11 different stains were screened on formalin-fixed, wax-embedded cells from five women. Samples were analysed qualitatively by examining staining patterns (colour) and morphology (absence or presence of nuclei). Three of the staining methods – Dane's, Csaba's and Ayoub-Shklar – were successful in distinguishing skin epithelial cells from buccal and vaginal. Second, cells were smeared directly onto slides, fixed with one of five fixatives and stained with one of the three stains mentioned above. Methanol fixation, coupled with the Dane's staining method, specific to keratin, was the only technique that distinguished between all three cell types. Skin cells stained magenta, red and orange and lacked nuclei; buccal cells stained predominantly orange–pink with red nuclei; while vaginal cells stained bright orange with orange nuclei and a blue extracellular hue. This staining pattern in vaginal cells was consistent in samples collected from 50 women aged between 18 and 67. Identification of cell type from unlabelled micrographs by 10 trained observers showed a mean success rate of 95%. The results of this study demonstrate that histological staining may provide forensic scientists with a technique for distinguishing between skin, buccal and vaginal epithelial cells and thus would enable more conclusive analyses when investigating sexual assault cases. 相似文献
922.
923.
Recent developments in German corporate governance 总被引:1,自引:0,他引:1
Marc Goergen Miguel C. Manjon Luc Renneboog 《International Review of Law and Economics》2008,28(3):175-193
This paper provides an overview of the German corporate governance system. We review the governance role of large shareholders, creditors, the product market and the supervisory board. We also discuss the importance of mergers and acquisitions, the market in block trades, and the lack of a hostile takeover market. Given that Germany is often referred to as a bank-based economy, we pay particular attention to the role of the universal banks (Hausbanken). We show that the German system is characterised by a market for partial corporate control, large shareholders and bank/creditor monitoring, a two-tier (management and supervisory) board with co-determination between shareholders and employees on the supervisory board, a disciplinary product–market, and corporate governance regulation largely based on EU directives but with deep roots in the German codes and legal doctrine. Another important feature of the German system is its corporate governance efficiency criterion which is focused on the maximisation of stakeholder value rather than shareholder value. However, the German corporate governance system has experienced many important changes over the last decade. First, the relationship between ownership or control concentration and profitability has changed over time. Second, the pay-for-performance relation is influenced by large shareholder control: in firms with controlling blockholders and when a universal bank is simultaneously an equity- and debtholder, the pay-for-performance relation is lower than in widely held firms or blockholder-controlled firms. Third, since 1995 several major regulatory initiatives (including voluntary codes) have increased transparency and accountability. 相似文献
924.
James C. McDavid Annette E. Mueller 《Canadian public administration. Administration publique du Canada》2008,51(4):589-615
Abstract: The primary purpose of this article is to investigate the factors that predict the efficiency of residential recycling collection services in Canadian local governments. The findings are based on a survey of 128 residential recycling producers from all regions of Canada. One of the most significant findings is the lack of a relationship between private‐sector companies collecting recyclables and the overall efficiency of collection operations. The dominance of the private‐sector collection of recyclables (over seventy‐seven per cent of all producers were contracted companies) does not translate into greater efficiencies. The most important variables in the model are amenable to local control. They include tonnes collected per vehicle per year, requiring full bins, inclusion of composting operations in the overall recycling program, the number of different kinds of materials recycled, participation rate, and reliance on side‐loading collection vehicles. Among the direct predictors of unit costs, the key underlying factor is the productivity of residential recycling operations. Because recyclables are marketed, handling them takes time, reduces the weights that collection vehicles can carry, and generally reduces productivity. Even diligent efforts to improve productivity will not bring recycling costs down to the levels for residential solid‐waste collection. Sommaire: L'objectif principal du présent article est d'examiner les facteurs qui prévoient l'efficacité des services de collecte de produits recyclables résidentiels dans les municipalités canadiennes. Les résultats reposent sur un sondage réalisé auprès de 128 producteurs de collecte de produits recyclables résidentiels opérant dans toutes les régions du Canada. L'un des résultats les plus notoires est le manque de relations entre les sociétés du secteur privé qui récupèrent les produits recyclables et l'efficacité d'ensemble des opérations de collecte. La prédominance de la collecte de produits recyclables par le secteur privé (plus de soixante‐dix‐sept pour cent de tous les producteurs étaient des sociétés contractuelles) ne se traduit pas par une plus grande efficacité. Les variables les plus importantes du modèle peuvent faire l'objet d'un contrôle local. Elles comprennent les tonnes récupérées par véhicule par an, l'exigence de poubelles pleines, l'inclusion d'opérations de compostage au programme général de recyclage, le nombre de différentes sortes de matériaux recyclés, le taux de participation, et le recours à des camions de collecte à chargement latéral. Parmi les variables explicatives directes des coûts unitaires, le principal facteur sous‐jacent est la productivité des opérations de recyclage résidentiel. Comme les produits recyclables sont commercialisés, leur manutention prend du temps, réduit le poids que les camions de collecte peuvent transporter, et réduit d'une manière générale la productivité. Même des efforts diligents pour améliorer la productivité ne feront pas baisser les coûts du recyclage aux niveaux de ceux de la collecte des déchets solides résidentiels. 相似文献
925.
Williamson Murray Author Vitae 《Orbis》2008,52(4):544-563
This article aims to delineate several issues raised by an historically based approach to understanding the present and the future. Beginning with a discussion of the profound impact that drastic changes have had on the international environment, the article then outlines what history suggests about human nature's influence on the course of future events; the future of war; the nature of governance and the United States. This essay does not attempt to provide answers, but rather suggests how policy makers, strategists, and military leaders might think through the complex political and cultural questions they need to be asking in the making of strategy. This is the essential first step for Americans. If they fail to ask the right questions, most answers will prove irrelevant to the challenges of the future. 相似文献
926.
Wang Xiaoyi 《International Understanding》2008,(3):38-40
At the invitation of Chinese Association for International Understanding (CAFIU), a 6-member delegation of American Foreign Policy Council headed by Mr. Peter Pace, former Chairman of the U.S. Joint Chiefs of Staff, visited China from June 4 to 11. 相似文献
927.
C. Robino S. Inturri A. Piccinini C. Torre 《Forensic Science International: Genetics Supplement Series》2008,1(1):160-161
Typing of X-chromosomal short tandem repeat (STR) loci in a deficiency paternity case revealed a single Mendelian incompatibility between a female child and her putative grandmother, consisting of an opposite homozygosity at locus DXS8378. The presence of a null allele due to a primer binding site mutation on the child's paternally inherited X chromosome was confirmed by amplification with newly designed DXS8378 external primers. Sequencing analysis showed a point mutation (C > T transition at position 168, according to GenBank accession G08098) in the binding site of the original DXS8378 reverse primer. 相似文献
928.
C. Baeza C. Gamba M.S. Mesa 《Forensic Science International: Genetics Supplement Series》2008,1(1):176-178
Short Tandem Repeat polymorphisms have been widely studied in the world, since specific databases are required to produce correct estimates of forensic statistical parameters. In this regard, Y-chromosome STRs have been studied mainly in Europe but are relatively scarce for sub-Saharan populations, despite these populations are represented in most of the Western countries. The aim of this work is to detect groups of populations with the lowest genetic variability within the African context. This allows to establish the relative homogeneity of Y-STRs databases for forensic casework and eventually to provide a wider insight into the African genetic history. 相似文献
929.
930.
Douglas Lemke 《American journal of political science》2008,52(4):774-786
In order to evaluate the applicability of power politics theories of war and international stability to interactions among nonstate actors, I test hypotheses from power transition theory and from neorealist arguments about systemic polarity against the behavior of 20 state and nonstate actors in nineteenth‐century South America. I find considerable support for two of the three hypotheses tested and conclude that existing IR theory has more explanatory power within the empirical domain of nonstate relations than critics of such theory claim. 相似文献