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971.
972.
In patrilineal societies, surnames and Y-specific haplotypes and haplogroups are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic genetics analysis. Here we evaluated this correlation in a sample of Central-Brazilian men. Surnames and Y-SNP haplogroup and Y-STR haplotype were analyzed in 55 pairs of Central-Brazilian men sharing surnames (n = 110). Seven haplogroups and thirty-two haplotypes have been observed, none correlated solely to any of the twenty-eight surnames represented here. In this sample, two men with the same surname showed a chance of 0.41 of sharing a Y-specific haplogroup. This chance is higher for surnames of intermediate frequencies, whereas rare surnames show distinct chances as zero and one. Observed results may be over-estimated due to a predominance of a specific haplogroup (P92R7 = 49%) in the sample, what makes it possible for two men with no coancestry to share this haplogroup. Considering STR, only three pairs of men shared haplotypes. The average difference between the haplotypes in each pair was 2.45 mutational steps. This relatively low correlation is due to some historical and cultural peculiarities of the country, what makes it improper for forensic purposes in Brazil.  相似文献   
973.
974.
Zusammenfassung Nach einer Entscheidung des Bayerischen Verfassungsgerichtshofs kann ein Bauleitplan wegen Versto? gegen das Willkürverbot aus Gründen des Umweltschutzes nichtig sein. Diese auf eine Popularklage ergangene Entscheidung er?ffnet die Frage, ob der Verfassungsgrundsatz des Willkürverbots auch im Rahmen von Verwaltungsakten herangezogen werden kann. Der Beitrag bejaht diese M?glichkeit.  相似文献   
975.
976.
A longitudinal study of 25 families, with children aged 14 months—5 years, in joint custody, is reported. Varying motivations that lead divorcing parents to undertake and sustain joint custody are discussed, together with the stresses and gratifications of these arrangements for the parents and children. Findings are that where both parents are motivated primarily by interest in the child, where the parenting is sensitive and where the child is shielded from interparental conflict, young children do well. Such families were not the majority in this study. Significant differences emerged in the adjustment of the 1–3 age group as compared with the 3–5 age group which point to greater difficulties for the 3–5 year-olds.  相似文献   
977.
DNA profiling evidence presented in court should be accompanied by a reliable estimate of its evidential weight. In calculating such statistics, allele frequencies from commonly employed autosomal microsatellite loci are required. These allele frequencies should be collected at a level that appropriately represents the genetic diversity that exists in the population. Typically this occurs at broadly defined bio-geographic categories, such as Caucasian or Asian. Datasets are commonly administered at the jurisdictional level. This paper focuses on Australian jurisdictions and assesses whether this current practice is appropriate for Aboriginal Australian and Caucasian populations alike. In keeping with other studies we observe negligible differences between Caucasian populations within Australia when segregated geographically. However segregation of Aboriginal Australian population data along contemporary State and Territory lines appears to mask the diversity that exists within this subpopulation. For this reason datasets collated along more traditional lines may be more appropriate, particularly to distinguish the most genetically differentiated populations residing in the north of the continent.  相似文献   
978.
We describe the forensic science application of a method for quantification of human genomic deoxyribonucleic acid (DNA). The two cases cited in this report involve DNA samples extracted from skin tissue and bloodstained clothing recovered from different crime scenes. High-molecular-weight DNA was recovered from both specimens, and the concentrations of these DNAs were estimated to be approximately 0.5 microgram/microL by ethidium bromide/agarose gel electrophoresis. Using the human-specific DNA probe p17H8 (locus D17Z1) to quantify the amount of human genomic DNA in these samples, it is shown that less than 1% of the DNA isolated from the skin tissue is of human origin and that the DNA isolated from the bloodstained clothing is effectively devoid of human DNA sequences. These case examples illustrate the need to quantify not only the total amount of DNA recovered from forensic casework material, but also the proportion of the DNA that is of human origin.  相似文献   
979.
The aim of this study was to determine whether polyurethane (PU) foam fragments from different sources could be discriminated from each other. Low and high power microscopy was used to determine whether or not foam fragments were distinguishable from each other under various lighting conditions. Once similar foam fragments were declared microscopically indistinguishable, the visible range microspectrophotometer was highly competent in further distinguishing the spectral characteristics in various fragments from each other. Foam fragments from the same source were shown to display no microscopical or chemical variation. Conversely, it was possible to make clear distinctions between foam fragments from different sources.  相似文献   
980.
The typing of certain polymorphic proteins present in human body fluids is an important aspect of the analysis of serological evidence. This is particularly true when dealing with evidence related to violent criminal activity such as homocide, assault, or rape. Until recently, the routine analysis of the genetic polymorphisms of interest relied upon conventional electrophoretic techniques such as horizontal starch or agarose slab gel or both, cellulose acetate, and vertical polyacrylamide gradient gel methods. These techniques adequately separate a limited number of common variants. In some cases, these methods are still those of choice. However, as a result of the nature of the conventional approach, problems with time required for analysis, resolution, diffusion of bands, sensitivity of protein detection, and cost are often encountered. Isoelectric focusing (IEF) offers an effective alternative to conventional electrophoresis for genetic marker typing. This method exploits the isoelectric point of allelic products rather than charge-to-mass ratio in a particular pH environment. The advantages of employing IEF include: reduction of time of analysis, increased resolution of protein bands, the possibility of subtyping existing phenotypes, increased sensitivity of detection, the counteraction of diffusion effects, and reduced cost per sample.  相似文献   
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