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301.
To determine if changes in fingerprint infrared spectra linear with age can be found, partial least squares (PLS1) regression of 155 fingerprint infrared spectra against the person's age was constructed. The regression produced a linear model of age as a function of spectrum with a root mean square error of calibration of less than 4 years, showing an inflection at about 25 years of age. The spectral ranges emphasized by the regression do not correspond to the highest concentration constituents of the fingerprints. Separate linear regression models for old and young people can be constructed with even more statistical rigor. The success of the regression demonstrates that a combination of constituents can be found that changes linearly with age, with a significant shift around puberty.  相似文献   
302.
Abstract: Differentiation of 21 glitter lip‐glosses from seven manufacturers was attempted by pyrolysis gas chromatography/mass spectroscopy. Samples were pyrolyzed on a ribbon probe at 800°C for 20 sec and analyzed with an Agilent® 6890N Network GC System and Agilent® 5973 Network Mass Selective Detector with MSD Productivity ChemStation® Data Analysis software. The total ion chromatograms obtained were examined and differences in the presence or absence of certain chromatographic peaks corresponding to certain pyrolysis products (e.g., styrene, cyclohexane) noted. In cases where the total ion chromatograms between lip‐glosses were similar, select ion profiling was performed. Of the 21 lip‐glosses, 15 were differentiated by either the total ion chromatograms alone or through select ion profiling. Considering that lip‐glosses are typically worn by young women (who are disproportionately victims of sexual assault), this study offers the potential of being able to provide investigative leads in sexual assault investigations with evidentiary samples of this kind.  相似文献   
303.
《刑法修正案(七)》第13条之解读   总被引:1,自引:0,他引:1  
《刑法修正案(七)》第13条的规定可以概括为两个罪名,即"密切关系人受贿罪"和"离职国家工作人员受贿罪"。"密切关系人"包括国家工作人员和离职国家工作人员的近亲属以及其他与之关系密切的人,其范围比"特定关系人"要广,除了近亲属、情妇(夫)和有共同利益的人之外,还可以是同学、老乡、同事、战友、朋友等。其实质在于,行为人基于与国家工作人员的这种关系,能够或者足以影响该国家工作人员或者其他国家工作人员,进而通过该国家工作人员或者其他国家工作人员职务上的行为,为请托人谋取利益,实现与请托人之间的权钱交易行为。由于近亲属等密切关系人和离职国家工作人员既可以构成受贿罪的共犯,也可以独立构成密切关系人受贿罪与离职国家工作人员受贿罪,因此,要将其与斡旋受贿、共同受贿等行为相区别。  相似文献   
304.
The goal of this study was to investigate whether pulmonary edema could become a specific diagnostic marker for fatal hypothermia using Fourier transform infrared (FTIR) spectroscopy in combination with chemometrics. The spectral profile analysis indicated that hypothermia fatalities associated with pulmonary edema fluid contained more β-sheet protein conformational structures than the control causes of death, which included sudden cardiac death, brain injury, cerebrovascular disease, mechanical asphyxiation, intoxication, and drowning. Subsequently, the results of principal component analysis (PCA) further revealed that the content of β-sheet protein conformational structures in the pulmonary edema fluid was the main discriminatory marker between fatal hypothermia and the other causes of death. Ultimately, a robust postmortem diagnostic model for fatal hypothermia using a partial least-squares discriminant analysis (PLS-DA) algorithm was constructed. Pulmonary edema fluid spectra collected from eight new forensic autopsy cases that did not participate in the construction of the diagnostic model were predicted using the model. The results showed the causes of death of all these eight cases were correctly classified. In conclusion, this preliminary study demonstrates that FTIR spectroscopy in combination with chemometrics could be a promising approach for the postmortem diagnosis of fatal hypothermia.  相似文献   
305.
《Science & justice》2020,60(1):63-71
The aim of this study was to compare three gunshot residue (GSR) collection methods used in conjunction with chemographic detection applied by different regional Swiss police services. The specimens were collected from the hands of a shooter with either filter paper (Filter method) or adhesive foil. The adhesive foil was then either applied against photographic paper during visualisation (AF Photo method) or coated with a layer of polyvinyl alcohol (AF PVAL method). The experiments involved two conditions of the examined hands, i.e. dry and humidified. The residues were revealed using the sodium rhodizonate test (SRT). Preliminary tests assessing the possibility of conducting a confirmatory Scanning Electron Microscopy coupled to Energy Dispersive X-ray spectroscopy (SEM/EDX) analysis after the chemographic test were performed on a number of specimens by cutting positive spots and mounting them on stubs. Obtained results were compared in terms of effectiveness - number of positive spots, time requirements, quality of subsequent SEM-EDX analysis, ease of use and cost.The Filter method generally yielded a high-quality detection with both dry and humidified hands, as well as a simple, quick and efficient confirmation by SEM/EDX. The AF Photo performed well on dry hands, but not on humidified hands. The AF PVAL method performance was lower compared to the other methods in both examined conditions of the hands. The SEM/EDX analysis showed that the Filter and AF PVAL method provided satisfactory results when a sufficient carbon coating thickness was applied to the cuttings. It was also observed that the thinner the PVAL layer, the better the quality of the spectra and obtained images in SEM/EDX. Furthermore, the surface of the photographic paper did not seem to be conductive, even after the application of a thick layer of carbon.In conclusion, the Filter method gave the best overall results, but its application required slightly more time and expertise than the two other methods.  相似文献   
306.
307.
王俊生 《当代韩国》2014,(2):113-123
本文以“中国知网”收录的有关朝鲜半岛问题的学术文献为研究对象,考察1979 ~2012年中国学界对朝鲜半岛问题的研究状况.在指标上,本文选取论文发表数量的年代分布、论文选题的主题分布、论文发文量居前6位的作者分布、论文发文量居前10位的单位分布、论文发文量居前10位的期刊分布、有关韩国研究和朝鲜研究的变迁对比这6个指标.通过对这些指标的详细考察,结论部分对1979 ~2012年中国有关朝鲜半岛问题研究的趋势和状况进行了基本描述,并从机制建设、研究方法革新、研究侧重点加强等几个层面提出了下一步研究时的建议.  相似文献   
308.
Ke Y  Zhang JG  Huang P  Lu QY  Fan SL  Xu YC  Wang ZY 《法医学杂志》2008,24(3):161-164
目的应用傅里叶变换红外(Fourier transform infrared.FTIR)光谱技术分析大鼠死后脑组织随死亡时间推移的化学变化过程,为死亡时间推断的研究提供新的途径与数据。方法大鼠断颈处死后置于(30±2)℃环境下,在不同时间点提取大鼠脑皮质.运用FTIR光谱仪检测不同化学基团的变化。结果随着死亡时间的推移,大鼠脑组织FTIR光谱的主要吸收峰峰位没有明显变化.而其峰强有明显差异:(1)与核酸有关的谱带的相对峰强呈明显下降趋势;(2)酰胺Ⅰ、Ⅱ的峰强比(I1647/I1541)呈下降趋势;(3)1456和1398cm^-1谱带的峰强各自呈下降和上升趋势;(4)2852、2871、2923和2958cm^-1谱带的峰强相对于1647cm^-1而言.呈上升趋势。结论脑组织可以作为FTIR光谱技术分析死亡时间的适用检材。  相似文献   
309.
目的 建立不同产地牛膝的红外光谱和红外导数光谱并对其差异性进行分析,为牛膝药材的快速鉴别提供依据.方法 运用傅里叶红外光谱技术结合二阶导数光谱对不同产地的牛膝药材进行鉴别,采用聚类分析和主成分分析对红外光谱数据进行统计分析.结果 牛膝的红外吸收峰主要在3289、2975、2890、1723、1630、1403、1321、1241、1018、927、814、773 cm-1附近,虽然不同产地牛膝所含化学成分具有相似性,但不同产地牛膝红外吸收峰的位置和相对强度存在一定差异;并且在二阶导数红外图谱的1800~800 cm-1波段中有更加明显差别,可以为其鉴别提供更准确的依据.聚类分析显示不同批次间相似度很高,主成分分析结果表明在1723、1630、927、814、651 cm-1等处的吸收峰对区分不同产地牛膝药材的贡献较大,内蒙古自治区赤峰市和河南省焦作市武陟县的牛膝药材综合评分较高.结论 红外光谱法与二阶导数光谱相结合不仅可以提供中药材所含化学成分的相关信息,还可以对其不同产地进行区分,实现对牛膝的快速鉴别.  相似文献   
310.
Abstract

The decisive role violence has played in the ordering of the Third World cannot be ignored or consigned to the past. Accordingly, we argue for a more systematic and determined attention to the connections between the devastation unleashed by colonialism, imperialism, and other forms of large-scale violence in the post-independence periods. In contradistinction to situating violence in and against the Third World as a backdrop of incomplete modernization, we recognize that its proper location is in the larger dynamics of racialized and colonial international relations. The articles in this volume address these dynamics of violence.  相似文献   
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