Accumulation of explosives in hair--Part 3: Binding site study

This study extends previous work on the sorption of explosives to the hair matrix. Specifically, we have studied the interaction of 2,4,6-trinitrotoluene (TNT) and triacetone triperoxide (TATP) as a function of chemical pretreatment with acetonitrile, neutral and alkaline hydrogen peroxide, methanolic KOH and potassium permanganate, and the morphological changes that accompany these treatments. While differences in vapor pressure can account for quantitative differences between TNT and TATP sorption, both are markedly affected by the chemical rinses. Examination of the hair surface shows different degrees of smoothening following rinsing, suggesting that the attachment to hair is largely a surface phenomenon involving the 18-methyleicosanoic acid lipid layer. Density functional theory calculations were employed to explore possible nucleation sites of TATP microcrystals on the hair. We conclude that some of the sites on melanin granular surfaces may support nucleation of TATP microcrystals. Moreover, the calculations support the experimental finding that dark hair adsorbs explosives better than light hair.     

Secondary Traumatic Stress in the Courtroom: Suggestions for Preventing Vicarious Trauma Resulting from Child Sexual Abuse Imagery

The internet and social media have added to an increase in sexual imagery. As a result, law enforcement, judicial officers and court ordered counselors will be exposed to an increase of images. While not every individual will experience post‐traumatic stress symptoms, it is anticipated there is risk for impact. The impact of viewing images can include an increase in vicarious trauma symptoms, burnout, and a possible decrease in impartiality. This paper offers suggestions for self‐care in the services of preventing collateral damage.     

Fragrance transfer between fabrics for forensic reconstruction applications

Sexual assault is a serious crime that often has low conviction rates. Recent literature has demonstrated that there is potential for fragrances to be valuable in forensic reconstructions where there has been contact between individuals. However, developing appropriate evidence bases for understanding the nature of fragrance transfer in these contexts is needed. This article presents three experiments that address the transfer process of fragrances that have been transferred from a primary piece of fabric onto a secondary piece of fabric, in a manner that could occur during an assault. The three variables studied were the ageing time of the fragrances on the first fabric prior to transfer, the contact time between the two fabrics, and lastly the fabric type (of the primary material and the recipient material). The transfer was evaluated using a validated solid phase micro-extraction gas chromatography–mass spectrometry (SPME GC–MS) method. The findings demonstrated that all three variables had an impact on the transfer of fragrances between clothing fabrics. Generally, lower volatility compounds were transferred and recovered in larger amounts than higher volatility compounds. All fragrance compounds were successfully recovered from a secondary piece of fabric even when the contact time was as short as 10 s, and even when the perfume was aged on the primary fabric for as long as 48 h. The nature of the fragrance transfer also depended on the fabric type, so that a clear discrimination was observed between the fragrance transfer that occurred onto a natural fabric (cotton) and onto a synthetic fabric (polyester).     

我国侵权法上特殊数人侵权责任分担制度立法体例与规则研究——兼评《侵权责任法（二次审议稿）》第14条及相关条文

从法律适用规则、内部责任份额和立法技术规则等角度可以将四种数人侵权责任分担形态区分为两类：一般数人侵权责任分担形态（包括按份责任形态和连带责任形态）、特殊数人侵权责任分担形态（包括补充责任形态和不真正连带责任形态）。立法技术上,在一般规则部分对特殊数人侵权责任形态的基本制度应予以规定,而对适用过错责任或过错推定责任的侵权行为类型的补充责任形态和适用严格责任的侵权行为类型中的不真正连带责任形态应予以全面列举。     

中专生自信心与家庭教养方式的关系研究

当代独生子女的家庭越来越多,家庭的教养方式对于青少年的成长,特别是对中专生的自信心的培养有着重要的内在关系。积极的家庭教养方式如情感温暖理解有利于青少年自信心的培养,而消极的教养方式如惩罚严厉、拒绝否认等不利于青少年自信心的建立。     

Pyrotechnic reaction residue particle analysis

Pyrotechnic reaction residue particle (PRRP) production, sampling and analysis are all very similar to that for primer gunshot residue. In both cases, the preferred method of analysis uses scanning electron microscopy to locate suspect particles and then uses energy dispersive x-ray spectroscopy to characterize the particle's constituent chemical elements. There are relatively few times when standard micro-analytical chemistry performed on pyrotechnic residues may not provide sufficient information for forensic investigators. However, on those occasions, PRRP analysis provides a greatly improved ability to discriminate between materials of pyrotechnic origin and other unrelated substances also present. The greater specificity of PRRP analysis is the result of its analyzing a large number of individual micron-sized particles, rather than producing only a single integrated result such as produced using standard micro-analytical chemistry. For example, PRRP analyses are used to demonstrate its ability to successfully (1) discriminate between pyrotechnic residues and unrelated background contamination, (2) identify that two different pyrotechnic compositions had previously been exploded within the same device, and (3) establish the chronology of an incident involving two separate and closely occurring explosions.     

Zur ultrastruktur vitaler,postmortaler und autolysierter gerinnsel

Investigations on animal experimental and human tissue material (skin, musculature, liver) with the scanning electron microscope are reported. These studies were carried out to clarify open questions on extravascular fibrin structures after blunt and sharp traumatization of vital and postmortem nature. The network formation which was already characterized earlier as typically vital and the irregular structure of postmortem coagula could be demonstrated even with modification of the traumatization, especially in tissue hematomas. Experimental investigations on autolysis revealed an exceedingly good preservation of the structure of vital coagulum material with massive damage and granular decomposition of fibrin fiber structures produced postmortem. The structural differences in the mode of interlinking of the fibrin was shown up especially clearly by the autolysis, which suggests an application as preparation technique for the question specified.Special modifications of the preparation technique (fixation according to Karnovsky, critical-point drying) did not provide such substantial advantages for routine investigations that they might be generally recommended.Sources of artefacts and possibilities of misinterpretation of findings as well as more advanced techniques are discussed.     

Identification of wires and the cutting tool by scanning electron microscope

The cut ends of aluminium and copper wires made by different pliers have been compared under the scanning electron microscope to correlate the two pieces of a wire and to identify the cutting tool. The mechanism of producing the cut ends has been discussed. Matching of extrusion marks and correspondence of breakages at the edges of the cut ends were observed. Correspondence between the fine striations was observed on the opposite faces. These features are put forward for assigning a cut wire to a source.The ends produced by repeatedly cutting a wire by the same portion of the edge of a pair of pliers have been compared. It was found that the striations and fracture zones were reproduced on the respective surfaces of the consecutive cut ends. To identify the cutting tool in wire theft cases, it is suggested that the trial cut ends can be made by cutting the wire with successive portions of the edge of the suspected tool and compare the surface features with that on the questioned ones.     

SD大鼠闭合性小脑挫伤的透射电镜观察

目的　探讨闭合性小脑挫伤病变发生发展过程。　方法　建立闭合性小脑挫伤动物模型 ,分别于损伤后不同时间组 5min、10min、3 0min、45min、60min、2h、4h、6h、8h、12h与正常组对照 ,观察其电镜变化。　结果　损伤后不同时间组 ,小脑蒲肯野氏细胞线粒体水肿、空泡化从轻到重 ,线粒体嵴逐渐消失。神经纤维髓鞘疏松断裂 ,神经原丝及微管结构模糊 ,并随着时间推移 ,其损伤越来越重。损伤后 3 0min ,线粒体胞浆中充满了游离核糖体。损伤后 1～ 2小时小脑蒲肯野氏细胞胞浆浓缩 ,细胞核开始发生染色质边集。个别细胞核发生核溶解。至 4～ 6小时小脑蒲肯野氏细胞细胞核坏死发展到高峰 ,然后逐渐减轻。损伤后 8小时 ,小脑血管内皮细胞线粒体水肿 ,嵴消失 ,神经纤维髓鞘松解 ,胶质细胞核周间隙扩张。　结论　闭合性小脑挫伤后不同时间电镜变化 ,为早期损伤时间推断的法医学鉴定提供了病理学基础。     

The determination of sequence of crossing strokes by the “Kromekote” paper lifting process and by the scanning electron microscopic method

The authors present the results obtained while applying the “Kromekote paper” lifting process first proposed by Igoe and Reynolds in 1979 [1] and later in a modified form in 1980 and 1982 by Godown [2]. They also present the results of their research to determine the writing order of crossing strokes using the Scanning Electron Microscopic technique, research that was restarted after the publication of an article by Waeschle [3].