Comparison of Catalytic and Immunological Amylase Tests for Identifying of Saliva from Degraded Samples

The stability of salivary α‐amylase is a critical factor in both catalytic and immunological method‐based forensic saliva identification. This study aimed to assess the sensitivity of catalytic and immunological tests on degraded saliva samples. Degraded saliva stains were prepared by microbial decomposition using humid soil. Salivary α‐amylase activity was catalytically detected both qualitatively and quantitatively using the Phadebas^® amylase test. As immunological methods, we conducted qualitative and quantitative tests using the RSID?‐saliva test and ELISA, respectively. Salivary α‐amylase activity of degraded samples (incubated at 37°C for 12 h) was significantly lower than that of controls in the quantitative tests. All the degraded samples obtained by the humid soil produced negative results in the Phadebas^® tests, but showed positive results in the RSID?‐saliva test and ELISA. These results suggest that immunological tests are effective for testing degraded saliva samples that have lost their enzymatic activity.     

Journey history reconstruction from the soils and sediments on footwear: An empirical approach

The value of environmental evidence for reconstructing journey histories has significant potential given the high transferability of sediments and the interaction of footwear with the ground. The importance of empirical evidence bases to underpin the collection, analysis, interpretation and presentation of forensic trace materials is increasingly acknowledged. This paper presents two experimental studies designed to address the transfer and persistence of sediments on the soles of footwear in forensically relevant scenarios, by means of quartz grain surface texture analysis, a technique which has been demonstrated to be able to distinguish between samples of mixed provenance.It was identified that there is a consistent trend of transfer and persistence of sediments from hypothetical pre-, syn- and post-crime event locations across the sole of the shoe, with sediments from ‘older’ locations likely to be retained in small proportions. Furthermore, the arch of the shoe (the area of lowest foot pressure distribution) typically (but not exclusively) retained the highest proportion of grain types from previous locations including the crime scene. A lack of chronological layering of the retained sediments was observed indicating that techniques that can identify the components of mixed provenance samples are important for analysing footwear sediment samples. It was also identified that the type of footwear appeared to have an influence on what particles were retained, with high relief soles that incorporate recessed areas being more likely to retain sediments transferred from ‘older’ locations from the journey history. In addition, the inners of footwear were found to retain sediments from multiple locations from the journey history that are less susceptible to differential loss in comparison to the outer sole. These findings provide important data that can form the basis for the effective collection, analysis and interpretation of sediments recovered from both the outer soles and inners of footwear, building on the findings of previously published studies. These data offer insights that enable inferences to be made about mixed source sediments that are identified on footwear in casework, and provide the beginnings of an empirical basis for assessing the significance of such sediment particles for a specific forensic reconstruction.     

ERCC1和XPF基因在法医学年龄推断中的初步研究

目的探讨ERCC1和XPF基因mRNA及蛋白在不同年龄段健康汉族人群中的表达情况,分析其mRNA和蛋白表达量与年龄之间的相关性,以期为法医学年龄推断提供新的分子生物学指标。方法收集150例不同年龄段健康汉族人群外周血样,梯度离心法分离血浆,Trizol法提取外周血单个核细胞(PBMCs)总RNA;实时荧光定量PCR检测ERCC1和XPF基因mRNA在PBMCs的相对表达量;酶联免疫吸附试验检测ERCC1和XPF蛋白在血浆中的表达量。结果 ERCC1和XPF基因mRNA在不同性别PBMCs的相对表达量均无统计差异(P0.05)。ERCC1和XPF基因mRNA相对表达量在不同年龄段有统计学差异(P0.05),且不同年龄段组间比较亦均有统计学差异(P0.05)。回归分析显示ERCC1和XPF基因mRNA相对表达量与年龄呈负相关,其相关系数(r)分别为-0.578和-0.844;以年龄为自变量(x),以mRNA相对表达量为因变量(Y),其拟合曲线分别为Y=3.3E-5x~2-0.0261x+1.9175(R~2=0.3244,P0.01)、Y=0.0003x~2-0.0459x+2.0439(R~2=0.729,P0.01)。血浆中ERCC1和XPF蛋白表达量在不同年龄段及性别间均无统计差异(P0.05)。结论 ERCC1和XPF基因mRNA在PBMCs的相对表达量随年龄增加而下降,其血浆中蛋白表达与年龄无关,为建立ERCC1和XPF基因与年龄之间的数学模型提供理论学依据。     

1H‐NMR with Multivariate Analysis for Automobile Lubricant Comparison

Identification of suspected automobile‐related lubricants could provide valuable information in forensic cases. We examined that automobile lubricants might exhibit the chemometric characteristics to their individual usages. To compare the degree of clustering in the plots, we co‐plotted general industrial oils that were highly dissimilar with automobile lubricants in additive compositions. ¹H‐NMR spectroscopy was used with multivariate statistics as a tool for grouping, clustering, and identification of automobile lubricants in laboratory conditions. We analyzed automobile lubricants including automobile engine oils, automobile transmission oils, automobile gear oils, and motorcycle oils. In contrast to the general industrial oils, automobile lubricants showed relatively high tendencies of clustering to their usages. Our pilot study demonstrated that the comparison of known and questioned samples to their usages might be possible in forensic fields.     

基于HPLC-TOF-MS代谢组学方法的溴鼠灵毒性作用评价

目的分析溴鼠灵中毒大鼠尿液的代谢特征,揭示溴鼠灵干预对大鼠毒性作用的分子机制。方法通过构建大鼠溴鼠灵中毒模型,采用高效液相色谱-飞行时间质谱(high performance liquid chromatographytime of flight mass spectrometry,HPLC-TOF-MS)获取大鼠尿液代谢轮廓,并用正交偏最小二乘法-判别分析(orthogonal partial least squares-discrimination analysis,OPLS-DA)进行多变量统计分析,找出与溴鼠灵毒性作用密切相关的差异代谢物。结果 OPLS-DA得分图显示给药前后不同时间的大鼠尿液样本代谢物轨迹在各时间段内相似度较好,呈现各自聚类现象。比较溴鼠灵给药前后大鼠尿液样本,筛选出22个与溴鼠灵毒性相关的差异代谢物。结论溴鼠灵主要通过干扰大鼠体内的三羧酸循环、糖酵解、鞘脂代谢和色氨酸代谢等代谢通路发挥毒性作用,且溴鼠灵毒性作用具有累积效应。基于尿液HPLC-TOF-MS代谢组学方法可为溴鼠灵毒性作用的分子机制研究提供新思路。     

缺氧相关microRNA在窒息死亡原因推断中的意义

在缺氧条件下microRNA(miRNA)能与转录因子等相互作用,调节细胞代谢,血管再生,血细胞生成,细胞增殖、分化及凋亡等生理过程,这些过程可能在窒息导致的死亡中发挥重要作用。本文拟对缺氧条件下miRNA的调节功能及缺氧对miRNA生物合成的影响进行综述,以期为miRNA在法医学窒息死亡原因推断中的研究提供新思路。     

金属硫蛋白1A和2A的mRNA时序性表达(英文)

目的研究大鼠肌肉挫伤后金属硫蛋白(metallothionein,MT)1A m RNA、MT2A m RNA的时序性表达。方法 54只SD大鼠被分成挫伤组(挫伤后0.5、1、6、12、18、24、30和36 h组各6只)和对照组(6只)。所有总RNA均取自大鼠的骨骼肌。利用SYBR GreenⅠ法进行RT-q PCR检测大鼠挫伤骨骼肌中MT1A m RNA、MT2A m RNA的相对表达量。结果 MT1A m RNA、MT2A m RNA在损伤后的变化趋势与损伤时间具有一定的相关性。除了挫伤后0.5 h组外,其余各组MT1A m RNA、MT2A m RNA的表达量与对照组相比差异均有统计学意义(P0.05)。损伤后1 h、6 h、12 h、18 h MT1A m RNA和MT2A m RNA的相对表达量呈现逐渐上升的趋势,在18 h时达到了峰值,分别为对照组的(239.41±15.20)倍和(717.42±50.76)倍;损伤后24 h时两者的表达量均明显减少;损伤后30 h再次上升,随后下降。结论 MT1A m RNA、MT2A m RNA可能对损伤时间推断有一定的意义。     

GC／MS检验1-苯基-1-丙酮和1-苯基-2-丙酮

目的阐明1-苯基-1-丙酮和1-苯基-2-丙酮在色谱行为、用途和受管制程度等方面的差异。方法使用GC／MS对1-苯基一1-丙酮和1-苯基-2-丙酮进行定性分析。结果1-苯基-1-丙酮和1-苯基-2-丙酮的保留时间相差约1min,特征离子显著不同。结论1-苯基-1-丙酮和1-苯基-2-丙酮虽然为同分异构体,且多数时中文名称都简称为苯丙酮,也都是制备毒品的原料,但其实二者在色谱行为、用途、管制程度上却有着巨大的差别。     

我国农村生态文明建设情况管窥--以“中央一号文件”为研究对象

生态文明建设,是我们党历来高度重视的一项战略任务与重要工作。新中国成立后,特别是改革开放以来,建设农村生态文明一直是党中央发展"三农"工作、解决"三农"问题的重要方面。其中,一个最突出的表现就是我们党历年所颁发的事关"三农"工作"中央一号文件",它凸显了我们党围绕农村生态文明建设所进行的顶层设计、决策部署和政策演进,也是各地区各部门做好农村生态文明建设工作的具体指导和根本遵循。     

Centred discourse,decentred practice: the relational production of Russian and Chinese ‘rising’ power in Central Asia

Abstract

This paper challenges dominant understandings of ‘rising powers’ by developing a decentred, relational account of Russia and China in Central Asia. We ask whether Moscow and Beijing’s regional integrative strategies do not guide, but rather are led by, everyday interactions among Russian and Chinese actors, and local actors in Central Asia. Rising powers, as a derivative of ‘Great Powers’, are frequently portrayed as structurally comparable units that concentrate power in their executives, fetishise territorial sovereignty, recruit client states, contest regional hegemony and explicitly oppose the post-1945 international order. In contrast, we demonstrate that the centred discourse of Eurasian integration promoted by Russian and Chinese leaders is decentred by networks of business and political elites, especially with regard to capital accumulation. Adopting Homi K. Bhabha’s notion of mimicry (subversion, hybridity) and J. C. Scott’s conception of mētis (local knowledge, agency), and using examples of Russian and Chinese investments and infrastructure projects in Central Asia, we argue that in order to understand centring discourse we must look to decentring practices at the periphery; that is, rising power is produced through ongoing interactions between actors at the margins of the state’s hegemonic reach.