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101.
The She ethnic is a large minority in China with approximately 700,000 individuals. For more than one thousand years, they mainly resided in Zhejiang and Fujian provinces. To obtain a better understanding of the genetic background of She, we investigate 21 autosomal STRs (A-STRs) and 16 X-STRs in 296 unrelated healthy individuals from Zhejiang She population. Allele frequencies and forensic parameters prove these markers are useful for forensic application. We also investigate the genetic background with the two types of markers. Nei genetic distances between She and Eastern Han population are always the lowest, regardless of the markers used for analysis. Although the tested STRs are located on different chromosomes with different inheritance laws, A-STRs and X-STRs provided in general congruent phylogenetic signal and similar cluster among compared groups. These results demonstrated that geographic isolation and interactions play significant roles in differentiation of genetic constitution of ethnic groups.  相似文献   
102.
Researches with RM Y-STRs have shown that these loci provide substantially higher haplotype diversity and haplotype discrimination capacity in worldwide populations when compared with the YSTRs commonly used in genetic forensics. The aim of this study was to develop an allelic frequency database for the Syrian population living in Turkey in order to obtain population data of 12 RM Y-STRs. A total of 80 unrelated males from the Syrian population living in Turkey were typed with 12 RM Y-STRs loci: DYF387S1, DYF399S1, DYF404S1, DYS449, DYS518, DYS526a/b, DYS547, DYS570, DYS576, DYS612, DYS626 and DYS627. The highest GD was observed for the locus DYF399S1 (0.91), followed by loci DYS449 (0.86) and DYS518 (0.83). RM Y-STR haplotype diversity was found 1.00 in these samples. Based on the results of this study, the RM YSTR loci showed remarkable haplotype resolution power in the Syrian population, high genetic diversity and, therefore, demonstrating their usefulness in forensic identification cases.  相似文献   
103.
Y-chromosomal short tandem repeats (Y-STRs) polymorphisms are useful in forensic identification, population genetics and constructing of human structures. Increasing the number of Y-STRs and their polymorphism will drastically narrow down the matching number of genealogy populations or pedigrees when searching against a forensic DNA databank. In this study, we develop a system containing 17 complementary Y-STRs that are compatible and reinforce the current commercially available Y-STR kits. This system was constructed by multiplex PCR with expected size of 126bp-400bp using home-made universal primers labeled by different fluorescence (DYS715, DYS709, DYS716, DYS713, DYS607, DYS718, DYS723, DYS708, DYS714, DYS712, DYS717, DYS721, DYS605, DYS719, DYS726, DYS598 and DYS722). The genetic data were obtained from 394 individuals in Shanxi province, China. The Y-STR system has 131 haplotypes and high discrimination power is 1. In conclusion, our study provides a robust, sensitive and cost-effective genotyping method for human identification, which is beneficial for narrowing the searching scope when applying to the genealogy searching with Y-STR DNA databank.  相似文献   
104.
Fifteen autosomal STRs were analyze in order to elucidate the differences between low and high land Ecuadorian population. Seven Ecuadorian geographic areas (Tisaleo-Mocha, Cañar, Quito, Rocafuerte, Santa Rosa, Guayaquil and Lago Agrio) from different altitude were selected for the study. After the analysis, little genetic distances were observed between all cities, the more distant cities (FST = 0.02354) were Rocafuerte at an elevation of 17 m.a.s.l. and Quito at 2850 m.a.s.l. and the similar cities (FST = 0.00033) were Rocafuerte (17 m.a.s.l.) and Santa Rosa (10 m.a.s.l). In conclusion, there is not a great genetic distance in the 15 STRs reported in high and low land Ecuadorian population, therefore previously reported frequencies could been used in identification and paternity cases under analysis.  相似文献   
105.
在人口老龄化不断加剧的情况之下,社会发展将更多地依赖于老年人的积极参与。而且随着长寿社会的到来,老年人的参与愿望和参与能力都在提升。日本是世界上人口老龄化程度最高的国家,已进入人口减少和超老龄社会。人口下降和老龄化将带来劳动力减少问题,对日本整个社会的均衡和可持续发展产生严重影响。为了应对劳动力不足问题,日本不仅修改《老年人就业稳定法》逐渐延长退休年龄,保障老年人继续工作,而且开展老年志愿者活动积极为退休的老年人创造再就业的环境。  相似文献   
106.
Facial approximations based on facial soft tissue depth measurement tables often utilize the arithmetic mean as a central tendency estimator. Stephan et al. (J Forensic Sci 2013;58:1439) suggest that the shorth and 75‐shormax statistics are better suited to describe the central tendency of non‐normal soft tissue depth data, while also accommodating normal distributions. The shorth, 75‐shormax, arithmetic mean, and other central tendency estimators were evaluated using a CT ‐derived facial soft tissue depth dataset. Differences between arithmetic mean and shorth mean for the tissue depths examined ranged from 0 mm to +2.3 mm (average 0.6 mm). Differences between the arithmetic mean plus one standard deviation (to approximate the same data points covered by the 75‐shormax) and 75‐shormax values ranged from ?0.8 mm to +0.7 mm (average 0.2 mm). The results of this research suggest that few practical differences exist across the central tendency point estimators for the evaluated soft tissue depth dataset.  相似文献   
107.
俄罗斯的人口现状与普京新方针的制定   总被引:4,自引:0,他引:4  
普京第 2次就任总统后,在其就职演说及随后向国会所做的致辞中,制定了发展经济、提高居民福利水平、消除贫困和军队的现代化等国家新的发展目标。俄罗斯人口的数量、密度、性别、民族构成及劳动力潜力的现状等人口因素对普京新方针带来了很大的影响。  相似文献   
108.
The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3-8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.  相似文献   
109.
Likelihood ratios are necessary to properly interpret mixed stain DNA evidence. They can flexibly consider alternate hypotheses and can account for population substructure. The likelihood ratio should be seen as an estimate and not a fixed value, because the calculations are functions of allelic frequency estimates that were estimated from a small portion of the population. Current methods do not account for uncertainty in the likelihood ratio estimates and are therefore an incomplete picture of the strength of the evidence. We propose the use of a confidence interval to report the consequent variation of likelihood ratios. The confidence interval is calculated using the standard forensic likelihood ratio formulae and a variance estimate derived using the Taylor expansion. The formula is explained, and a computer program has been made available. Numeric work shows that the evidential strength of DNA profiles decreases as the variation among populations increases.  相似文献   
110.
人口增长与经济快速发展,自然灾害频发与投机资本炒作,粮食安全问题成为世界关注问题。中国作为人口大国和快速发展国家,粮食安全问题受到世界关注,保障粮食安全已经成为中国政府的国家发展战略。世界粮食安全问题,不只是吃饭问题,而是国家生存问题,粮食已经成为战略资源。  相似文献   
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