计算机入侵动态取证技术研究

计算机取证是打击计算机犯罪的有效手段,传统的计算机取证大多采用事后分析的静态取证技术,证据的采集不够及时、全面,经恢复的数据可能是已经被篡改,因而法律效力低。可以运用一种将计算机取证技术与入侵检测技术结合的入侵动态取证系统,动态收集识别入侵证据,及时分析、提取证据至证据库中保存。此系统采用认证、加密、隔离等安全手段,确保了证据在传送、保存过程中的真实性、准确性及不可篡改性,使其成为有效的法庭证据,实现了计算机取证的及时性、智能性。     

交通事故常见的微量物证及其提取方法

交通事故现场常见微量物证主要有油漆物证、塑料和树脂物证、纤维物证、橡胶和轮胎物证、汽车玻璃物证以及法医物证等。交通事故现场中的微量物证在确定事故责任和侦破交通肇事逃逸犯罪中起着至关重要的作用。因此 ,事故勘验人员应引起高度重视 ,注意掌握正确的提取方法。     

河豚毒素的检验

通过对食用河豚鱼干致死案例的系统毒物分析,本文详细介绍了有关体内河豚毒素的固相萃取方法,利用本方法成功地解决了一起因河豚毒素中毒案件的检验,从死者胃内容、心血中均检出河豚毒素,从死者吃剩的干鱼片中检出1.4μg/g的河豚毒素.     

Sensitive Method for the Confident Identification of Genetically Variant Peptides in Human Hair Keratin

Recent reports have demonstrated that genetically variant peptides derived from human hair shaft proteins can be used to differentiate individuals of different biogeographic origins. We report a method involving direct extraction of hair shaft proteins more sensitive than previously published methods regarding GVP detection. It involves one step for protein extraction and was found to provide reproducible results. A detailed proteomic analysis of this data is presented that led to the following four results: (i) A peptide spectral library was created and made available for download. It contains all identified peptides from this work, including GVPs that, when appropriately expanded with diverse hair-derived peptides, can provide a routine, reliable, and sensitive means of analyzing hair digests; (ii) an analysis of artifact peptides arising from side reactions is also made using a new method for finding unexpected modifications; (iii) detailed analysis of the gel-based method employed clearly shows the high degree of cross-linking or protein association involved in hair digestion, with major GVPs eluting over a wide range of high molecular weights while others apparently arise from distinct non-cross-linked proteins; and (v) finally, we show that some of the specific GVP identifications depend on the sample preparation method.     

微波提取山茱萸马钱素的工艺研究W

以山茱萸为原料，在微波场的作用下，进行了不同微波提取溶剂、料液比、提取时间、提取温度、提取功率和正交优化实验对山茱萸中马钱素提取率的影响研究。结果表明：影响微波提取的因素依次为提取时间、提取温度、提取功率。优选方案为：微波提取溶剂为水，料液比1∶30，提取时间10min, 提取温度70℃，提取功率300W,山茱萸马钱素提取率为0.80%。     

一种改良骨骼DNA的提取方法

采用十六烷基三甲基溴化铵(简称CTAB)及两次纯化浓缩的方法提取骨骼DNA,利用荧光标记复合扩增、自动毛细管电泳与分型的技术,成功检测到14个STR位点的分型.该方法稳定、结果可靠,为严重降解骨骼DNA的提取提供了一种可参用的方法.     

用Chelex100法及有机溶剂提取法联合提取DNA扩增STR基因座的比较研究

为了比较不同方法提取DNA扩增STR基因座的成功率 ,本文用Chelex10 0法及Chelex10 0法联合有机溶剂提取法分别提取性犯罪案件 6份血斑及 6份混合斑中精子DNA ,并用PE公司ProfilerPlus系统复合扩增 ,ABI 310型基因分型仪检测。结果表明 ,常规采用Chelex10 0法提取血斑及精斑等生物检材DNA作STR基因座检验失败或所检测的位点较少时 ,应对Chelex10 0法提取的DNA上清液再用有机溶剂提取法提取 ,可极大提高DNA检验成功率。采用本文建立的Chelex10 0法联合有机溶剂提取法 ,提高了PCR扩增阳性率 ,对实际检案很有帮助 ;在PCR扩增前应常规进行DNA定量检验 ,否则对于重要检材应进行梯度扩增。     

国产圆珠笔油墨字迹书写时间的鉴别

对国产圆珠笔油墨字迹书写时间的鉴别进行了实验研究,达到了检测速度快,实用性强,费用低的效果.     

利用压力循环仪提取骨骼DNA

目的探讨建立利用压力循环技术提取骨骼DNA的新方法。方法将11个不同部位骨骼样品分成3组,一组采用本实验室常规方法处理骨骼,一组采用压力循环仪处理骨骼,另外一组作为阴性对照,然后统一进行DNA的提取及定量。结果采用压力循环技术提取骨骼DNA时间比实验室常规方法缩短24小时以上,提取效率提高6%～49%。结论压力循环技术可以作为一种提取骨骼DNA提取的新方法之一。     

Evaluation of Commercial Kits for Dual Extraction of DNA and RNA from Human Body Fluids, ,

STR typing of DNA evidence can identify the donor with a high power of discrimination but cannot identify the tissue origin of a body‐fluid stain. Using RNA to attribute a crime scene stain to a particular tissue may aid in reconstruction efforts. With blood from 10 donors, four DNA and RNA coextraction kits were evaluated by measuring yields and STR and mRNA profiles. T tests indicated some significant differences in kit performance. The Zymo Research ZR‐Duet^? kit performed best based on average DNA (41.4 ng) and mRNA (4.07 ng) yields and was the only kit to provide complete DNA/RNA profiles for all samples. The consistency of this kit was challenged by data from additional blood and saliva donors. Further testing is advised before a superior kit is unequivocally chosen. Stand‐alone DNA or RNA purification generally offers higher yield, but coextraction may still allow successful STR profiling and tissue source identification.