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981.
Abstract: Racemization method is currently considered to be one of the most accurate methods for age estimation. There are many factors that affect racemization reaction velocities. We investigated ethnic differences in the racemization reaction velocities between Japanese and Scandinavian teeth. After a heating experiment, the Arrhenius equation was used to obtain a rate constant (k). Both groups presented almost identical velocities, indicating that there was no difference in the tooth racemization reaction between the two groups. However, because 14 of the 18 Scandinavian teeth had multiple roots, it is possible that accurate racemization rates of the teeth themselves were not reflected in the results. These findings reconfirm that the type of tooth selected is extremely important when evaluating age by racemization. 相似文献
982.
Camperlengo LT Shapiro-Mendoza CK Kim SY 《The American journal of forensic medicine and pathology》2012,33(3):197-201
Using a 2004 population-based survey of all US medical examiner and coroner offices, we examined the characteristics of offices accepting an infant death case and calculated the percentage of offices that had death scene investigation or autopsy policies for the investigation of sudden unexpected infant death (SUID). We also calculated the percentage of offices that used and did not use sudden infant death syndrome (SIDS) as a cause of death, and we compared differences in characteristics among those offices.Of medical examiner and coroner offices, 52% did not report an infant death in 2004. Of the 7957 infant deaths reported, 43% occurred in jurisdictions that experienced 1 or 2 infant deaths. Of the offices that used SIDS as a classification, 34% did not have policies for conducting death scene investigations and autopsies for SUID. At least 5% of offices that reported an infant death did not use SIDS as a cause of death classification. These findings have important implications for understanding recent trends in SIDS and SUID. Supporting the implementation of national standards for investigating and certifying infant deaths could provide guidelines for consistent practices in medical examiner and coroner offices. 相似文献
983.
Sasaoka S Saito K Higashi K Limwikrant W Moribe K Suzuki S Yamamoto K 《Forensic science international》2012,220(1-3):59-66
This study focused on two-dimensional fast Fourier transform (2D-FFT) as a new technique for the discrimination of kraft tapes, which is a kind of adhesive packing tape. The 2D power spectrum (2D-PS) obtained by applying 2D-FFT to an image enables us to obtain information about the spatial periodicity, even if the periodicity is invisible within the image. However, in the case of kraft tape, peaks in the 2D-PS are too unclear to determine its periodicity. We developed novel analytical image processes combined with 2D-FFT. 2D-FFT was applied to 50 randomly selected areas in a transmitted light image of kraft tape. The 2D-PSs were calculated from each area without applying a logarithmic transformation, accumulated, and processed by the removal of the area surrounding the center, and finally normalized for visualization. These processes enhanced the peaks and eliminated local variations. Through an intra-roll comparison, the 2D-PSs collected from a roll were similar in the location of the peaks and in their patterns at low frequency area. Using an inter-roll comparison, the 2D-PSs from 50 commercially available brand-name products were classified into 26 groups based on these peaks and patterns. All results demonstrate that this method, which is convenient, rapid, and non-destructive, could be a valuable tool for the identification of kraft tapes. 相似文献
984.
Frederickx C Dekeirsschieter J Brostaux Y Wathelet JP Verheggen FJ Haubruge E 《Forensic science international》2012,219(1-3):215-220
To evaluate postmortem intervals (PMIs), one should take into account the determined age of necrophagous flies present on the cadaver. However, PMI determination needs further improvement, and rapid and accurate approaches have therefore to be developed. While previous studies have focussed on insect cuticular hydrocarbons, here we explore the volatile profile released by larvae and pupae of Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). We monitored changes in volatile compounds daily, by headspace solid-phase microextraction, followed by gas chromatography-mass spectrometry. Branched and unbranched hydrocarbons, alcohols, esters and acids were identified, and the volatile profile was shown to vary, in both composition and quantity, with the age of the larva/pupa under investigation. We concluded, based on the analysis of the released volatile organic compounds, that it is possible to increase the accuracy of the estimated PMI, through improved estimation of the age of blowflies present on the cadaver. 相似文献
985.
Unlike some of its Western counterparts, where the first line of defence against corruption and unethical behavior has been a reliance on a public service ethos, the Hong Kong government has traditionally relied on strict compliance with rules and regulations in its successful drive against bureaucratic malpractices. Since 1997, however, a changing political, economic and administrative environment has also seen efforts to introduce a more value-based approach to integrity. This article examines the factors that have led to the modification of the Hong Kong government??s strategy and evaluates its success in the wider theoretical context of the relationship between a predominantly rule-based and a value-based approach to integrity management. 相似文献
986.
目的 考察纤维屑在涉及二次转移案件中作为示踪物质的适用性.方法 根据一个实际案例展开,在该案中,犯罪嫌疑人涉嫌多起入室盗窃案.纤维开始分散于嫌疑人所用车辆,后被嫌疑人“携带”并分散到犯罪现场,最终这些纤维在勘查过程中被收集.设计完善了一个可用于散布纤维的便携式装置,并完成了一系列二次转移的相关实验.结果 设计的装置可在短时间均相的散布纤维,单次接触不能全部转移第一表面的纤维碎屑.只有1-15%的纤维会转移到代表犯罪现场的第三表面.实际转移的纤维数与包括比如表面的材质在内的各种因素都有关系.结论 在所选参数范围内,相对大量的纤维有可能转移到犯罪现场并在现场勘查过程中被提取. 相似文献
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