Profiling the scent of weathered training aids for blood-detection dogs

At outdoor crime scenes, cadaver-detection and blood-detection dogs may be tasked with locating blood that is days, weeks or months old. Although it is known that the odour profile of blood will change during this time, it is currently unknown how the profile changes when exposed to the environment. Such variables must be studied in order to understand when the odour profile is no longer detectable by the scent-detection dogs and other crime scene tools should be implemented. In this study, blood was deposited onto concrete and varnished wood surfaces and weathered in an outdoor environment over a three-month period. Headspace samples were collected using solid phase microextraction (SPME) and analysed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC–TOFMS). The chemical odour profiles were compared with the behavioural responses of cadaver-detection and blood-detection dogs during training. Data interpretation using principal component analysis (PCA) and hierarchical cluster analysis (HCA) established that the blood odour could no longer be detected using SPME–GC×GC–TOFMS after two months of weathering on both surfaces. Conversely, the blood-detection dogs had difficulty locating the blood samples after one month of weathering on concrete and after one week of weathering on varnished wood. The scent-detection dogs evaluated herein had not been previously exposed to environmentally weathered blood samples during training. Given that this study was conducted to test the dogs' baseline abilities, it is expected that with repeated exposure, the dogs' capabilities would likely improve. The knowledge gained from this study can assist in providing law enforcement with more accurate training aids for blood-detection dogs and can improve their efficiency when deployed to outdoor crime scenes.     

Reading Václav Havel in the Age of Trump

This paper explores the explicit self-deprecation in Vaclav Havel’s writings in order to outline a unique contribution to thinking about resistance contained in Havel’s oeuvre. What Havel offers is a timely critique of messianic political gestures. I will focus on how Havel’s self-deprecation offers a subtle but significant critique of western politics which also contains the kernal of a virtue ethics of sorts, instead of a blueprint for radical action. I will also explain the important and related critique of messianic politics entailed in Havel’s thought and outline the significance of this critique for the current political climate.     

完善我国刑事证人作证制度的立法构想

本文对我国刑事证人作证制度提出了从立法、司法实践、社会因素三个方面进行完善的构想。     

略谈职务侵占案件线索的初查

《刑事诉讼法》赋予了公安机关打击职务侵占犯罪的职责 ,但公安机关尚未对该类案件线索的初查作出具体规定。为了提高对该类案件线索初查的成案率 ,加大对此类犯罪的打击力度 ,侦查人员在初查此类犯罪案件时应注意 :熟悉研究职务侵占案件线索 ,确定初查的范围 ,制定初查的计划 ;询问报案人、线索举报人、控告人和调查外围知情人 ,进行财务检查 ;把握应注意的事项。     

产毒素多杀巴氏杆菌在猪萎缩性鼻炎病因中的作用研究——给用醋酸处理或不处理的猪接种产毒素多杀巴氏杆菌引起的鼻腔病变比较

用产毒素多杀巴氏杆菌单独接种到未作任何处理的仔猪鼻腔,细菌被迅速清除,鼻甲骨不发生明显萎缩。对仔猪鼻腔用1％醋酸预先处理2天后,再接种产毒素多杀巴氏杆菌,该菌则可在鼻腔长期定居,引起严重的鼻甲骨萎缩;如再混合感染支气管败血波氏杆菌时,猪萎缩性鼻炎的病理变化和临床指征明显加重。试验结果表明,与支气管败血波氏杆菌一样,某些非传染因素也可促进产毒素多杀巴氏杆菌在猪鼻腔定居,从而导致持续性萎缩性鼻炎的发生。     

中外双边投资条约中经济主权问题研究

本文对经济主权的实质、内容和特征进行探讨 ,并从中外双边投资条约的内容入手 ,对我国坚持经济主权原则之体现和弊漏作出分析 ,提出经济主权之实现应注意的问题。     

镇眩汤对梅尼埃病大鼠血管加压素的影响

目的 探讨中药复方镇眩汤治疗梅尼埃病的机制。方法 采用阻塞前庭导水管的方法复制梅尼埃病模型,观察大鼠用药前后听觉诱发电位听阈的变化及大鼠血浆中血管加压素的含量。结果 与假手术组比较,模型组大鼠听觉诱发电位听阈和血浆血管加压素水平显著升高;与模型组比较,镇眩汤高、中剂量组大鼠听阈和血管加压管水平显著降低（P＜0.05）。结论 镇眩汤治疗梅尼埃病的机制与其调节血浆血管加压素有关。