白鸡屎藤挥发油抗肠炎沙门菌内毒素作用的分析

为了探讨白鸡屎藤挥发油抗肠炎沙门菌内毒素的作用,将420只7日龄三黄鸡随机分成A、B、C、D、E、F组并对A、B、C组鸡按100μg/mL(1mL)预防用药,在12日龄时对A、B、D、E组口服肠炎沙门菌攻毒,攻毒24h后对A、D组按100μg/mL白鸡屎藤挥发油1mL进行滴鼻给药治疗,同时将不同质量浓度的白鸡屎藤挥发油与内毒素混合对另外90只雏鸡进行肌肉注射攻毒,并进行试验鸡与攻毒鸡临床死亡情况统计、病理组织学观察和肝与血液生化指标测定。结果显示,白鸡屎藤挥发油对肠炎沙门菌内毒素具有灭活作用,可缓解血清ALT和AST活性的升高或使其降低(P<0.01或P<0.05),提升肝及血清中SOD的活性(P<0.01或P<0.05),使肝中MDA含量下降和延缓其升高。结果表明,白鸡屎藤挥发油具有抗肠炎沙门菌内毒素的作用,其机理与其保肝作用和抗氧化损伤作用有关。     

大鼠死后肌肉电导率与腐败程度的关系

目的分析大鼠死后肌肉电导率(electrical conductivity,EC)、肉类食品腐败程度指标挥发性盐基氮(total volatile basic nitrogen,TVB-N)与死亡时间(postmortem interval,PMI)的关系,探讨EC作为尸体肌肉腐败程度评价指标的可行性,为该法用于PMI推断奠定理论基础。方法健康SD大鼠颈椎脱臼处死后,保存在28℃环境中,于死后不同时间点提取大鼠后肢肌肉组织,用去离子水制成质量浓度为0.1 g/m L的肌肉浸渍液,并测量所得浸渍液的EC值和TVB-N含量。分析EC(x_1)与TVB-N(x_2)的相关性,建立二者关系的回归方程;分析两指标与PMI的相关性,并分别建立两指标与PMI(y)关系的回归方程。结果肌肉浸渍液EC、TVB-N随PMI的变化曲线走势基本相同;EC与TVB-N呈显著直线正相关,回归方程为x_2=0.14 x1-164.91(R~2=0.982);EC、TVB-N与PMI显著相关,回归方程分别为y=19.38 x_1~3-370.68 x_1~2+2 526.03 x1-717.06(R~2=0.994),y=2.56 x_2~3-48.39 x_2~2+330.60 x_2-255.04(R2=0.997)。结论大鼠死后肌肉EC与TVB-N变化趋势一致,可以作为反映尸体肌肉腐败程度的指标,为腐败尸体PMI推断的相关研究提供方法。     

Fourier-transformed infrared breath testing after ingestion of technical alcohol

The study aim was to evaluate the feasibility of a Fourier-transformed infrared (FT-IR) analyzer for out-of-laboratory use by screening the exhalations of inebriated individuals, and to determine analysis quality using common breath components and solvents. Each of the 35 inebriated participants gave an acceptable sample. Because of the metabolism of 2-propanol, the subjects exhaled high concentrations of acetone in addition to ethanol. Other volatile ingredients of technical ethanol products (methyl ethyl ketone, methyl isobutyl ketone, and 2-propanol) were also detected. The lower limits of quantification for the analyzed components ranged from 1.7 to 12 microg/L in simulated breath samples. The bias was +/-2% for ethanol and -11% for methanol. Within-day and between-day coefficients of variation were <1% for ethanol and <4% for methanol. The bias of ethanol and methanol analyses due to coexisting solvents ranged from -0.8 to +2.2% and from -5.6 to +2.9%, respectively. The FT-IR method proved suitable for use outside the laboratory and fulfilled the quality criteria for analysis of solvents in breath.     

Decomposing Human Blood: Canine Detection Odor Signature and Volatile Organic Compounds

The admissibility of human “odor mortis” discrimination in courts depends on the lack of comprehension of volatile organic compounds (VOCs) during the human decay process and of the lack in standardized procedures in training cadaver dogs. Blood was collected from four young people who died from traffic accidents and analyzed using HS‐SPME/GC‐MS at different decompositional stages. Two dogs, professionally trained, were tested to exactly locate blood samples, for each time point of the experiment. We found a long list of VOCs which varied from fresh to decomposed blood samples, showing differences in specific compounds. Dog performance showed a positive predictive value between 98.96% and 100% for DOG A, and between 99.47% and 100% for DOG B. Our findings demonstrated that decomposing human blood is a good source of VOCs and a good target for canine training.     

白鸡屎藤挥发油对患肠炎沙门氏菌病鸡肠黏膜的影响

将7日龄三黄鸡240只分成A、B、C、D、E、F组,并对A、B、C组按1g/kg剂量用白鸡屎藤挥发油滴鼻预防,在12日龄时对A、B、D、E组口服肠炎沙门氏菌(攻毒)建模,攻毒后第24小时对A、D组按1g/kg剂量用白鸡屎藤挥发油滴鼻治疗;同时,通过病理组织学方法测试雏鸡小肠肠绒毛密度、长度和直径,小肠隐窝及小肠横断面肥大细胞数量的变化;最后,比较隐窝、小肠横断面肥大细胞数量及小肠绒毛密度、长度和直径的显著性变化,以探讨白鸡屎藤挥发油对患肠炎沙门氏菌病雏鸡的治疗作用机制。结果显示,白鸡屎藤挥发油可显著降低感染肠炎沙门氏菌雏鸡小肠隐窝的深度(P<0.01),使患鸡小肠肠绒毛长度、密度及小肠横断面肥大细胞数量恢复正常(P>0.05)。结果表明,白鸡屎藤挥发油对感染肠炎沙门氏菌的雏鸡的治疗作用机理与其对雏鸡小肠隐窝深度的降低作用和对小肠肠绒毛的恢复作用有关。     

论计算机取证相关问题——现场动态分析，获取“易挥发”数字证据

由于目前计算机专业取证人员数量的不足，当前司法实践中对于现场中正处于运行状态的计算机大多采用“二步式”取证的方式来搜集数字证据。即先由侦查人员对涉案计算机实施关机分离和保全。尔后再移交专业机构进行数字证据司法鉴定。这种方式虽然保障了数字证据的原始性和证明力。但无形之中造成了存储在RAM中的“易挥发”数据以及其他形式的潜在数字证据的丢失。而计算机信息系统中的这些“易挥发数据”可以为案件的侦破提供重要线索和潜在的数字证据。因此通过对侦查人员的专业培训．实现“易挥发数据”的现场动态获取和合理保全对数字案件侦查取证意义重大。     

Volatile Emission of Decomposing Pig Carcasses (Sus scrofa domesticus L.) as an Indicator for the Postmortem Interval

This study aimed at correlating selected carcass borne volatile organic compounds (VOCs) with the postmortem interval (PMI). Selected volatiles should 1st be reliably emitted during vertebrate decay, 2nd be emitted at high concentrations, and 3rd show a reproducible quantitative dynamic during the decaying process. Four pigs (Sus scrofa domesticus L.) were placed in a deciduous forest in different seasons and volatiles emitted during the decaying process were sampled. Seventeen compounds were identified and quantified by GC-MS. Electrophysiological experiments on the antenna of female Calliphora vicina and additional data of Dermestes maculans were used as an evolutionary tuned information filter to evaluate the 1st criterion. The relative quantitative emission of hexanal, nonanal, dimethyl disulfide, dimethyl trisulfide, 1-butanol, and phenol were correlated with the PMI, and the observed stages of decay and the limitations of this model were discussed.     

The Name of the Rose

Party names have been collected since ‘Whig’ and ‘Tory’ meant ‘Scotch rebel’ and ‘Irish bandit’. ‘Conservative’ began as a catch‐all on the right when one did not use the word ‘right’ in politics, struggled with ‘Unionist’ until Ireland got away and was a euphemism for ‘Tory’ before the Americans used it to describe howling extremists. ‘Labour’ meant skilled men in best suits and school teachers with elbow patches, and now has the resonance of Nineveh and Tyre.     

Responses of Lucilia sericata Meigen (Diptera: Calliphoridae) to cadaveric volatile organic compounds

Flies of the Calliphoridae Family are the most forensically important insects because of their abundance on the decedent during the first minutes following death. Necrophagous insects are attracted at a distance by a decomposing body, through the use of volatile chemical cues. We tested the possible attractive role of some volatile organic chemicals (VOCs) released by decaying cadavers, on male and female of Lucilia sericata Meigen (Diptera: Calliphoridae). Two complementary approaches were used. Electroantennography (EAG) allowed identifying the semiochemicals that are detected by the olfactory system of L. sericata. Dose-response tests with EAG showed that dimethyl disulfide (DMDS) and butan-1-ol elicited the highest responses. Behavioral assays showed that, among the VOCs tested, DMDS and butan-1-ol are attractive for L. sericata, while the other VOCs are repulsive or do not cause any behavior. Our results may have potential implications in a better understanding of attractiveness of blowflies toward a corpse.     

In‐Depth Analysis of Computer Memory Acquisition Software for Forensic Purposes

The comparison studies on random access memory (RAM) acquisition tools are either limited in metrics or the selected tools were designed to be executed in older operating systems. Therefore, this study evaluates widely used seven shareware or freeware/open source RAM acquisition forensic tools that are compatible to work with the latest 64‐bit Windows operating systems. These tools' user interface capabilities, platform limitations, reporting capabilities, total execution time, shared and proprietary DLLs, modified registry keys, and invoked files during processing were compared. We observed that Windows Memory Reader and Belkasoft's Live Ram Capturer leaves the least fingerprints in memory when loaded. On the other hand, ProDiscover and FTK Imager perform poor in memory usage, processing time, DLL usage, and not‐wanted artifacts introduced to the system. While Belkasoft's Live Ram Capturer is the fastest to obtain an image of the memory, Pro Discover takes the longest time to do the same job.