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排序方式: 共有780条查询结果,搜索用时 31 毫秒
51.
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Lareu M Puente J Sobrino B Quintáns B Brión M Carracedo A 《Forensic science international》2001,118(2-3):163-168
A novel methodology based on PCR monitoring on-line with fluorescent formats using the LightCycler for Y chromosome SNP typing is proposed. The main advantages of the system are the time necessary for the analysis (which is around 20 min), the robustness and the accuracy of the method and especially its sensitivity, which permits the detection of the male component in male-female mixtures up to 1:300 for some of the SNPs.Singleplexes of four different SNPs (M9, sY81, SRY-1532 and SRY-2627) as well as two duplexes (M9 and sY81 on the one hand and SRY-1532 and SRY-2627 on the other) were efficiently implemented. A simultaneous amplification and analysis of the four SNPs is also possible. It seems difficult with the current methodology to implement more than a quadruplex. 相似文献
53.
Szejnwald Brown Halina Angel David P. Broszkiewicz Roman Krzyśków Barbara 《Policy Sciences》2001,34(3-4):247-271
The societal transformation underway in Poland createda fundamental challenge to the occupational health and safety system, as the ideological and administrative principles on which it was founded vanished along with the communist-dominated regime. This paper examines the regulatory reform in Poland during the 1990s: its structural elements, implementation record and future prospects. Drawing on five case studies of privatized firms, a mailed questionnaire, and policy and institutional analysis, we find that Poland had considerable success in developing an effective regulatory system for managing occupational health hazards in privatized sector while also achieving considerable socioeconomic progress. The fundamental legitimacy of the regulators and regulatory process, the availability of information about firms and regulatory intents, and the capacity for case-specific decision making, are among the key explanatory factors. The case-specific implementation in Poland is consistent with models advocated by several authors in relation to other industrialized European economies (termed variously as negotiated compliance, tit-for-tat, cooperation-deterrence), despite a uniquely Polish context related to the continuing legacy of the communist era. The study also shows how in Poland a good fit between regulatory institutions and policies on the one hand, and their social context on the other hand, contributes to the effectiveness of the regulatory system. 相似文献
54.
Francesca Gains 《Public administration》1999,77(4):713-730
This article examines the implementation of privatization policies in two ‘Next Steps’ agencies. This is discussed with reference to the broader theoretical and empirical questions of how do institutions change and when are political actors constrained in implementing their policy choices. Cortell and Peterson’s framework for explaining institutional change, and the concept of intra-state policy networks are used to analyse the cases. The differential outcomes identified illustrate how constraints operate and how these may be overcome by strategic actors to produce change. Constraints in these cases arose from fragmentation and dependence in central government, from differing institutionalized beliefs and from the development of intra-state networks between the departments and agencies. The paper concludes by suggesting that the type of intra-state networks created through agencification can be seen to have an effect on policy outcomes and are worthy of more detailed research. 相似文献
55.
Calculation of age from fetal and newborn remains may be problematic, and when these remains are altered by maceration, decomposition or burning, age may be more difficult to discern. When soft tissue indicators are transformed, then two techniques exist for accurate age determination; dental development, which may prove difficult given the degree of tissue alteration; and appearance, size and fusion of ossification centers, including diaphyseal length, which may yield inaccurate ages if shrinkage is not accounted for. This study is undertaken to facilitate age calculation by systematically re-evaluating diaphyseal shrinkage and determine shrinkage rates from wet to carbonized states and wet to calcined states using Petersohn and K?hler's data, originally published in German and then published in Fazekas and Kósa (1978:362-369). Average shrinkage, standard deviation, minimum and maximum values are calculated for each diaphysis and then for all diaphyses between 4-10 lunar months (LM) and for newborns. Associated values for carbonized diaphyses are: 4 LM--32.50% +/- 12.12%; 5 LM--14.04% +/- 4.44%; 6 LM--6.78% +/- 1.06%; 7 LM--4.18% +/- 0.31%; 8 LM--3.47% +/- 0.42%; 9 LM--3.05% +/- 0.18%; 10 LM--2.46% +/- 0.67%; and in newborns 2.16% +/- 0.29%. Similar values for calcined diaphyses are: 4 LM--40.11% +/- 17.51%; 5 LM--18.29% +/- 4.42%; 6 LM--9.84% +/- 1.27%; 7 LM--9.82% +/- 0.51%; 8 LM--9.42% +/- 0.72%; 9 LM--9.45% +/- 0.33%; 10 LM--8.94% +/- 0.37%; and in newborns 8.96% +/- 0.49%. These findings suggest that percent shrinkage due to carbonization and calcination is greatest in the earliest age groups, decreasing substantially with advancing age. The rates of shrinkage, however, vary by the burning process utilized and age group studied. These general findings are similar to those of Petersohn and K?hler, yet specific values for percent shrinkage vary greatly from values cited in this analysis. These data provide a means to assess the degree of shrinkage that occurs for each diaphysis for each given age group. 相似文献
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C. Phillips A. Salas J.J. Snchez M. Fondevila A. Gmez-Tato J. lvarez-Dios M. Calaza M. Casares de Cal D. Ballard M.V. Lareu . Carracedo The SNPforID Consortium 《Forensic Science International: Genetics Supplement Series》2007,1(3-4):273-280
Tests that infer the ancestral origin of a DNA sample have considerable potential in the development of forensic tools that can help to guide crime investigation. We have developed a single-tube 34-plex SNP assay for the assignment of ancestral origin by choosing ancestry-informative markers (AIMs) exhibiting highly contrasting allele frequency distributions between the three major population-groups. To predict ancestral origin from the profiles obtained, a classification algorithm was developed based on maximum likelihood. Sampling of two populations each from African, European and East Asian groups provided training sets for the algorithm and this was tested using the CEPH Human Genome Diversity Panel. We detected negligible theoretical and practical error for assignments to one of the three groups analyzed with consistently high classification probabilities, even when using reduced subsets of SNPs. This study shows that by choosing SNPs exhibiting marked allele frequency differences between population-groups a practical forensic test for assigning the most likely ancestry can be achieved from a single multiplexed assay. 相似文献
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Valerio Onofri Ilaria Boschi Francesca Scarnicci Gianmarco Ferri Cristian Capelli 《Forensic Science International: Genetics Supplement Series》2008,1(1):233-234
In the recent years the Y chromosome genealogy has been refined by a number of newly discovered SNPs. The non-random distribution of the Y chromosome lineages worldwide makes fundamental the dissection and characterisation of haplogroups associated with specific geographic areas. In Southern Europe the haplogroup J2, as defined by the M172 marker, can reach frequencies up to 35%, making the dissection of such lineage critical for population studies. Here we present a study on J2 chromosomes from the Italian peninsula. Populations and forensic implications are discussed. A total of 900 individuals were previously genotyped for a number of SNPs, including M172. More than 200 of these have been now genotyped for 7 SNPs within the J2 lineage using a multiplex SNaPshot approach. The different distribution of the various lineages in different geographic areas probably reflects different historical demographic events and points to differential Y chromosome haplotype distribution, with implication for forensic application of this genetic marker. 相似文献