502指印的光学加强方法研究

目的通过对502胶指印的光学加强研究,找出最佳502胶指印拍摄提取照明方法。方法对三种客体上的指印各100枚分别用502胶熏显,并用四种不同照明方法进行比较。结果不同客体上的502胶指印,需根据不同情况选择不同照明方法拍摄提取。结论本研究结果对实际应用有较大参考价值。     

利用纳米粉体显现光滑客体汗潜指纹

纳米粉体材料色彩丰富,且对各种客体都有一定的吸附能力。这里介绍了应用吹显技术对14种纳米粉体材料在玻璃、瓷器、油漆等不同光滑客体表面遗留汗潜指纹的显现方法,实验证明显现效果较好。     

一种指纹快速比对的新方法

目的　提出一种大容量指纹数据的快速比对新方法。方法　采用多处理机并行比对技术 ,通过专用软件调动多处理机并行工作。结果　使指纹比对实现了快速化、准确化和性价比最优化。结论　解决了专用硬件产品价格昂贵且兼容性差、升级困难而仅靠优化比对软件算法提高速度终有极限的难题     

用α-珠旦白-3’HVR探针研究DNA指纹

用α-珠蛋白-3’HVR探针,经Southern印迹法,对100名不相关个体及4个家系的32名相关个体的DNA指纹进行了检测,所产生的DNA图谱具有高度的个体特异性,在被测的所有个体中无一相同。经统计学计算表明,任意两个个体DNA指纹图重合率为10~(-11)。家系分析毒明,DNA片段严格按照孟德尔方式遗传。该探针的应用,将在法医学亲子鉴定和个人同一认定中发挥重要的作用。     

Detection of visible and latent fingerprints using micro-X-ray fluorescence elemental imaging

Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods.     

使用油红O显现潮湿纸张上的油脂手印

通过使用物理显影液(PD)和油红O(ORO)试剂在潮湿纸张上做了指纹显现效果的比对,发现ORO在热敏纸和白纸上比PD表现出更好的效果,但是牛皮纸上效果不明显。ORO很少破坏物证,可作为潮湿纸张上指纹显现的良好方法。     

新型亲油性纳米二氧化硅粉末在手印显现中的应用

目的 比较新型亲油性纳米二氧化硅粉末显现手印的效果.方法 应用亲油性纳米二氧化硅粉末与现场勘查箱内金粉、银粉和黑色磁性粉显现非渗透性客体表面油汗混合手印,并在自然光下观察比较显现效果.结果 亲油性纳米二氧化硅粉末显现出的手印图像纹线清晰连贯,背景反差好.结论 亲油性纳米二氧化硅粉末显现手印具有一定的优势.     

酸性黄显现非渗透性客体上血潜手印初步探究

目的建立一种酸性黄显现非渗透性客体上血潜手印的方法。方法制备白色瓷砖、黑色塑料袋、黑色瓷瓶、易拉罐侧面、深色铁质茶叶盒等为客体的捺印手印,配置以酸性黄作为主要成分的染色剂,对其进行固定、染色、漂洗,在多波段光源下观察。结果在440nm激发光源条件下,通过橙色护目镜观察有很强的黄色荧光特征。结论酸性黄显现法具有操作简单、显现效果明显、能排除深色背景干扰的特点,容易推广使用。     

“502”加膜一染色法显现油质手印

目的探索方便快捷并有效的油质手印显现方法。方法用“502”熏显常见玻璃、粗糙皮革等不同客体上不同遗留时间的油汗手印和多油手印,加染后用透明胶带粘取。结果显现了30天左右大多数非渗透性客体上的油质加层手印,10天左右渗透性客体上的油质渐层手印。结论本方法适用于油质加层手印及部分油质渐层手印的显现,显出手印清晰,流畅,不破坏手印。     

Toward multidimensional information: A derivatization-free UHPLC-QqQ MS/MS method for amino acid components of fingerprint

The analysis of fingerprint chemical composition is a meaningful way to excavate the multidimensional information of fingerprint, including the donor profiling information and the age of a fingerprint, which broadens the evidential values of fingerprint, especially for the partial and distorted fingerprint. But the research remains still in the pilot phases or is ongoing. Amino acids are the dominant organic substances in latent sweat fingerprint and influenced by many donor factors. Hence, their content reflects personal information of donors. Forensic science will be revolutionized if suspects can be individualized by their amino acid content. The diverse nature, distinct physicochemical properties, and ultra-micro levels of amino acids present in fingerprints make it hard to detect. A high sensitivity method for detecting and quantifying multiple amino acid components is required. UHPLC-QqQ MS/MS offers high sensitivity, high separation, simultaneous multicomponents detection, and no derivatization, making it an ideal method for detecting and analyzing amino acids in fingerprints. Therefore, in this study, we propose and validate an efficient UHPLC-QqQ MS/MS method for the extraction and analysis of 13 amino acids from fingerprint. We compared the results of amino acids of 10 different substrates and found that the inherent amino acids in most porous substrates would have been extracted along with the fingerprint amino acids, making them unsuitable for quantitative amino acid analysis. Instead, plastic sheets are ideal substrates for laboratory studies. Then, extensive experiments were conducted among 30 donors for multidimensional information analysis. The type of samples analyzed were eccrine-rich fingerprints. A Binary Logistic Regression (BLR) model was developed, and the female and male donors were successfully differentiated by amino acids in fingerprints. Two other mathematical models were also developed to verify the accuracy, and all three different mathematical models were able to identify donors of different genders with over 90% accuracy. This demonstrates that amino acids have the potential to provide more information for donors as metabolic markers. In the future, we will conduct a series of experiments to analyze more multidimensional information for individual identification by amino acid content in the fingerprint.