The detection of clandestine graves in an arid environment using thermal imaging deployed from an unmanned aerial vehicle

The Middle East is one of the world regions that has frequently suffered from armed conflicts that resulted in mass burials. However, the detection of clandestine graves in such an arid environment by deploying remote sensing payload on unmanned aerial vehicles (UAVs) has received little attention. The present study used a UAV equipped with a thermal sensor aimed at narrowing down the search area of possible gravesites in the arid climate of Kuwait. The enclosed research area, which includes both control and experimental mass graves, was imaged for 18 months. The variation in topsoil temperature and soil moisture between the graves and their surroundings was evaluated. The results of the analysis demonstrated the effectiveness of thermal imaging techniques in detecting heat produced from buried sheep carcasses and detecting the change in grave soil moisture for our research environment for 7 and 10 months, respectively. The buried animals significantly influenced the topsoil temperature (p = 0.044), while the height from which the images were captured had an insignificant effect on the measured temperature within the range tested (p = 0.985). Furthermore, there was a negative correlation (−0.359) between grave temperature and the calculated soil moisture. The results from these cost- and time-effective search methods presented in this study confirm their potential for the detection of burial sites in an arid environment.     

氨基比林血痕预试验处理血痕后样本的DNA定量

目的：探讨氨基比林血痕预试验处理血痕后样本DNA含量的变化及对STR分型检测的影响。方法10名健康无关个体EDTA抗凝血液制成滤纸血痕,氨基比林血痕预试验检测,按试验后血样干燥保存时间分30 min、1 h、3 h、6 h、12 h、24 h共6个实验组,并采用磁珠法、QIAcube DNA纯化法、Chelex-100法三种方法提取样本DNA,应用荧光定量PCR检测样本DNA含量,PCR-STR荧光技术进行STR分型。结果提取方法相同时,氨基比林血痕预试验后血样随干燥保存时间的延长,样本DNA含量呈逐渐降低的趋势。保存时间相同时,不同DNA提取方法间,样本DNA含量差异也有统计学意义。90.56%样本均可获得16个STR基因座明确分型。结论氨基比林血痕预试验对血痕样本DNA有损伤,24 h内多可获有效STR分型。磁珠法提取样本DNA进行STR分型,效果最好。     

基于MRI的中国汉族成人颅面径线测量与分析

目的通过MRI和VGStudio MAX 2.2软件对中国汉族成人颅面相关径线进行测量,并分析其与性别、年龄、身高以及体重的关系。方法按颅面标志点设定4条径线。A径线：在正中矢状面上颏下点至头顶点的最大直线距离;B径线：在正中矢状面上发际点至后头点的最大直线距离;C径线：在水平面上左、右外眼点间的最大直线距离;D径线：在冠状面上左、右侧颧点间的最大直线距离;用VGStudio MAX 2.2软件对MRI图像数据进行三维重建,直接用软件的测量工具对颅面的相关径线进行测量,并用SPSS 16.0进行分析。结果 A、B、C、D径线的均值分别为（237.54±8.63）mm、（173.07±8.28）mm、（89.58±4.46）mm、（127.34±8.16）mm,与性别有着显著性差异（P〈0.01）;其中A、C、D径线与身高,A、D径线与体重,C径线与年龄,均存在明显的直线相关关系。结论中国汉族成人颅面径线A、B、C、D均存在明显的性别差异;且A、C、D径线与身高,A、D径线与体重,C径线与年龄,均存在明显的直线相关关系。     

Using Spatial,Temporal and Evidence‐status Data to Improve Ballistic Imaging Performance

Firearms identification imaging systems help solve crimes by comparing newly acquired images of cartridge casings or bullets to a database of images obtained from past crime scenes. We formulate an optimization problem that bases its matching decisions not only on the similarity between pairs of images, but also on the time and spatial location of each new acquisition and each database entry. The objective is to maximize the detection probability subject to a constraint on the false positive rate. We use data on all cartridge casings matches detected in Israel during 2006–2008 to estimate most of the model parameters. We estimate matching accuracy from two different studies and predict that the optimal use of extraneous information would increase the detection probability from 0.931 to 0.987 and from 0.707 to 0.844, respectively. These improvements are achieved by favoring pairs of images that are closer together in space and time.     

CT‐Guided,Minimally Invasive,Postmortem Needle Biopsy Using the B‐Rob II Needle‐Positioning Robot

CT‐guided, minimally invasive needle biopsy techniques can be used to retrieve tissue or body fluid samples for histologic tissue diagnoses in forensic investigations. The purpose of this study was an evaluation of CT‐guided needle‐positioning robot B‐Rob II. To operate under CT guidance, we adopted the B‐Rob II robotic needle placement system and its workflow. The accuracy and speed of the procedure were tested on a gelatin phantom in a series of 21 biopsies. We achieved an average needle placement accuracy of 1.8 mm (±1.1 mm) using robotic assistance. The procedure required an average of 2 min 21 s. The needle placement accuracy for minimally invasive needle biopsies using the B‐Rob II biopsy robot is sufficiently accurate and fast for forensic postmortem examinations of focal organ changes. Further tests will be performed to test the feasibility of the robot for performing biopsies of focal organ changes in human bodies.     

Can the RUVIS Reflected UV Imaging System Visualize Fingerprint Corrosion on Brass Cartridge Casings Postfiring?

Comparisons are made between the visualization of fingerprint corrosion ridge detail on fired brass cartridge casings, where fingerprint sweat was deposited prefiring, using both ultraviolet (UV) and visible (natural daylight) light sources. A reflected ultraviolet imaging system (RUVIS), normally used for visualizing latent fingerprint sweat deposits, is compared with optical interference and digital color mapping of visible light, the latter using apparatus constructed to easily enable selection of the optimum viewing angle. Results show that reflected UV, with a monochromatic UV source of 254 nm, was unable to visualize fingerprint ridge detail on any of 12 casings analyzed, whereas optical interference and digital color mapping using natural daylight yielded ridge detail on three casings. Reasons for the lack of success with RUVIS are discussed in terms of the variation in thickness of the thin film of metal oxide corrosion and absorption wavelengths for the corrosion products of brass.     

磁珠直接吸附法对体态检材游离DNA的提取

目的采用磁珠直接吸附法对人体尿液、唾液、血液3种体态生物检材中的游离DNA进行提取检验,为法医物证中游离DNA的研究及检验工作提供参考。方法对3种生物检材采取离心吸取上清液的方法分离游离DNA,然后采用磁珠直接吸附法进行提取纯化,Identifiler-Plus试剂盒进行复合扩增后常规STR检测。结果在3种检材中均检出了游离DNA,其中血液中游离DNA检出率为100%,唾液为90%,尿液为70%。结论人体体态生物检材中存在游离DNA,同时磁珠直接吸附法可高效、快捷的提取生物检材中的游离DNA。     

The application of infrared chemical imaging to the detection and enhancement of latent fingerprints: method optimization and further findings

Fourier transform infrared (FTIR) chemical imaging allows the collection of fingerprint images from backgrounds that have traditionally posed problems for conventional fingerprint detection methods. In this work, the suitability of this technique for the imaging of fingerprints on a wider range of difficult surfaces (including polymer banknotes, various types of paper, and aluminum drink cans) has been tested. For each new surface, a systematic methodology was employed to optimize settings such as spectral resolution, number of scans, and pixel aggregation in order to reduce collection time and file-size without compromising spatial resolution and the quality of the final fingerprint image. The imaging of cyanoacrylate-fumed fingerprints on polymer banknotes has been improved, with shorter collection times for larger image areas. One-month-old fingerprints on polymer banknotes have been successfully fumed and imaged. It was also found that FTIR chemical imaging gives high quality images of cyanoacrylate-fumed fingerprints on aluminum drink cans, regardless of the printed background. Although visible and UV light sources do not yield fingerprint images of the same quality on difficult, nonporous backgrounds, in many cases they can be used to locate a fingerprint prior to higher quality imaging by the FTIR technique. Attempts to acquire FTIR images of fingerprints on paper-based porous surfaces that had been treated with established reagents such as ninhydrin were all unsuccessful due to the swamping effect of the cellulose constituents of the paper.     

Four new illicit cocaine impurities from the oxidation of crude cocaine base: formation and characterization of the diastereomeric 2,3-dihydroxy-3-phenylpropionylecgonine methyl esters from cis- and trans-cinnamoylcocaine

Four new impurities have recently been detected in the gas chromatographic signature profiles of many illicit cocaine hydrochloride exhibits. These impurities are only seen in exhibits that have been oxidized and are most prominent in samples that have been highly oxidized. Exhibits containing these compounds were subjected to gas and liquid chromatographic-mass spectrometric analyses to determine the identity of the impurities. These impurities were subsequently synthesized to verify their structures. Four diastereomeric diols formed from the oxidation of cis- and trans-cinnamoylcocaine were characterized by nuclear magnetic resonance spectrometry, mass spectrometry, and synthesis. Oxidation of cis-cinnamoylcocaine in neutral conditions yielded (2R,3R)-dihydroxy-3-phenylpropionylecgonine methyl ester and (2S,3S)-dihydroxy-3-phenylpropionylecgonine methyl ester, while trans-cinnamoylcocaine produced (2R,3S)-dihydroxy-3-phenylpropionylecgonine methyl ester and (2S,3R)-dihydroxy-3-phenylpropionylecgonine methyl ester. The recent appearance of these new impurities suggests that some illicit cocaine processors have modified their oxidation procedures of crude cocaine base for transformation into illicit refined cocaine hydrochloride.