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141.
Cristiano O. L. Goulart MS Clésia C. Nascentes PhD Letícia M. Costa PhD 《Journal of forensic sciences》2023,68(5):1713-1720
The recovery of identifiable fingerprints from fired cartridge cases is challenging. Therefore, the characterization of chemical modifications and their effects on fingerprint integrity post-firing is essential. In this study, the primary fingerprint lipids, including myristic acid, pentadecanoic acid, palmitoleic acid, palmitic acid, stearic acid, squalene, and cholesterol in fired and unfired cartridges, were extracted with acetonitrile, followed by derivatization using N,O-Bis(trimethylsilyl)trifluoroacetamide with 1% trimethylchlorosilane (BSTFA/1%TMCS). Squalane was used as the internal standard, and all quantifications were performed using gas chromatography coupled with mass spectrometry using a triple-quadrupole mass filter. All lipids identified in the unfired cartridges were also detected in the fired cartridges, and statistical analysis using Student's t-test and F tests was performed with a 95% confidence level. The concentration of lipids in the unfired cartridges was found to be similar to that detected in the fired cartridges, except for squalene, the recovery of which was 28% lower in the fired cartridges. 相似文献
142.
程代娣 《安徽警官职业学院学报》2008,7(1):87-89
Microsoft SQL Server2000是比较成熟的大型关系数据库管理系统(DBMS),其理论基础建立在强大的关系模型理论基础之上,其安全机制建立在数据库的认证、授权等策略之上,其认证又分为操作系统(OS)级和数据库认证两个层次。从SQL Server 2000安全模型着手,针对该数据库管理系统存在的数据安全问题,从多个方面进行探索性总结和分析,并给出详尽的解决方案,这对实现数据的保密性、完整性和有效性极其重要。 相似文献
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H. David Sheets Ph.D. Anne Torres B.S. Glenn Langenburg Ph.D. Peter J. Bush B.S. Mary A. Bush D.D.S. 《Journal of forensic sciences》2014,59(4):1113-1120
Friction ridge impression appearance can be affected due to the type of surface touched and pressure exerted during deposition. Understanding the magnitude of alterations, regions affected, and systematic/detectable changes occurring would provide useful information. Geometric morphometric techniques were used to statistically characterize these changes. One hundred and fourteen prints were obtained from a single volunteer and impressed with heavy, normal, and light pressure on computer paper, soft gloss paper, 10‐print card stock, and retabs. Six hundred prints from 10 volunteers were rolled with heavy, normal, and light pressure on soft gloss paper and 10‐print card stock. Results indicate that while different substrates/pressure levels produced small systematic changes in fingerprints, the changes were small in magnitude: roughly the width of one ridge. There were no detectable changes in the degree of random variability of prints associated with either pressure or substrate. In conclusion, the prints transferred reliably regardless of pressure or substrate 相似文献
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目的探讨纹线中空特征应用于某些残缺、特征数量不足的指纹检验中的可行性。方法引入指纹三级特征理论,从该特征的存在机理、稳定性特点及与其它类似特征的区别等进行观察。结果纹线中空特征稳定存在,且在比对工作中具有可操作性。结论纹线中空特征是对常规特征的补充,对指纹比对工作具有实际意义。 相似文献
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目的探索油墨捺印指纹显现三级特征稳定性的影响因素,排除主观条件的影响。方法在最适宜的条件下,通过油墨捺印采集不同压力下的指纹样本,清晰地显出指纹三级特征,用高分辨率扫描仪扫描试验样本,保存指纹样本,最后分析了指纹汗孔、细点线、纹线形态、皱纹等三级特征的反映性及稳定性,确定其鉴定价值。结果油墨捺印法对三级特征的反映性不够理想,汗孔、纹线形态特征、细点线特征及皱纹在不同压力下的稳定性较差。其中,各个三级特征在轻压下的反映性及稳定性较为接近实际,捺印的压力越大则三级特征变形越大,甚至完全变形成为另外一种特征。结论所以如果将此法应用于指纹比对时,仍需进一步的研究与改进。 相似文献
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Hanns W. Maull 《German politics》2013,22(2):1-3
In the Kosovo crisis, Germany for the first time since 1955 joined NATO military combat operations in a major way. While this has often been interpreted as a fundamental major departure ('normalisation') in Germany's post‐war foreign policy, this article argues that Germany's willingness to contemplate joining a NATO war even without a mandate by the UN Security Council represents an evolution, rather than a fundamental change in Germany's foreign policy orientation. This evolution can be explained best as a logical and consistent response of Germany's foreign policy identity which reconciled, through modification, its traditional post war foreign policy identity as a ‘civilian power’ to a radically different security environment. 相似文献