Rapid Localization of Bone Fragments on Surfaces using Back‐Projection and Hyperspectral Imaging

Manual localization of bone fragments on the ground or on complex surfaces in relation to accidents or criminal activity may be time‐consuming and challenging. It is here investigated whether combining a near‐infrared hyperspectral camera and chemometric modeling with false color back‐projection can be used for rapid localization of bone fragments. The approach is noninvasive and highlights the spatial distribution of various compounds/properties to facilitate manual inspection of surfaces. Discriminant partial least squares regression is used to classify between bone and nonbone spectra from the hyperspectral camera. A predictive model (>95% prediction ability) is constructed from raw chicken bones mixed with stone, sand, leaves, moss, and wood. The model uses features in the near‐infrared spectrum which may be selective for bones in general and is able to identify a wide variety of bones from different animals and contexts, including aged and weathered bone.     

肋骨骨折影像学在法医鉴定中的应用及相关问题

肋骨骨折法医学的诊断主要依靠医学影像学检查结果,影像学的误诊或漏诊将直接影响鉴定意见的准确性,从而可能导致刑事或民事案件的审判错误。本文详尽地总结和分析了肋骨骨折各种影像学检查技术的优缺点、漏误诊原因、法医学鉴定现状及法医鉴定时需考虑的因素,以提高法医学鉴定的准确性。     

发光光谱成像检验人民币真伪研究

目的建立鉴别人民币真伪和假币来源同一的检验方法。方法运用发光光谱成像技术对1999版和2005版真币人民币各50张、1999版和2005版假币各12张进行检验。结果真假人民币之间和不同来源的假币之间均能较好的区分开,区分效果明显。结论发光光谱成像技术可以有效鉴别真假人民币和假币来源是否同一。     

数字化技术在法医颅脑损伤生物力学分析中的应用

颅脑损伤是法医学鉴定的重点和难点,传统的颅脑损伤生物力学分析存在技术手段陈旧、分析数据模糊等问题。基于影像学的虚拟解剖技术和有限元分析技术具有非侵入、细节还原充分和力学数据准确等优点,在颅脑损伤生物力学分析中引入先进的数字化技术可提高鉴定证据客观性,推动学科的发展。     

Automated Mapping of Explosives Particles in Composition C‐4 Fingerprints*†‡

Abstract: A method is described to perform automated mapping of hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX) particles in C‐4 fingerprints. The method employs polarized light microscopy and image analysis to map the entire fingerprint and the distribution of RDX particles. This method can be used to evaluate a large number of fingerprints to aid in the development of threat libraries that can be used to determine performance requirements of explosive trace detectors. A series of 50 C‐4 fingerprints were characterized, and results show that the number of particles varies significantly from print to print, and within a print. The particle size distributions can be used to estimate the mass of RDX in the fingerprint. These estimates were found to be within ±26% relative of the results obtained from dissolution gas chromatography/μ‐electron capture detection for four of six prints, which is quite encouraging for a particle counting approach. By evaluating the average mass and frequency of particles with respect to size for this series of fingerprints, we conclude that particles 10–20 μm in diameter could be targeted to improve detection of traces of C‐4 explosives.     

Variation in the Measurement of Cranial Volume and Surface Area Using 3D Laser Scanning Technology

Abstract: Three‐dimensional (3D) laser scanner models of human crania can be used for forensic facial reconstruction, and for obtaining craniometric data useful for estimating age, sex, and population affinity of unidentified human remains. However, the use of computer‐generated measurements in a casework setting requires the measurement precision to be known. Here, we assess the repeatability and precision of cranial volume and surface area measurements using 3D laser scanner models created by different operators using different protocols for collecting and processing data. We report intraobserver measurement errors of 0.2% and interobserver errors of 2% of the total area and volume values, suggesting that observer‐related errors do not pose major obstacles for sharing, combining, or comparing such measurements. Nevertheless, as no standardized procedure exists for area or volume measurements from 3D models, it is imperative to report the scanning and postscanning protocols employed when such measurements are conducted in a forensic setting.     

运用Photoshop软件检验追加打印文件

传统方法很难检验追加文本内容打印变造的文件。运用图像处理软件Photoshop对追加文本内容的打印文件可疑之处的字体墨迹进行放大观察,对可疑之处字体笔画特征进行比对,对字间距、行间距进行测量比对检验,可以作出正确的检验结论。运用Photoshop软件对追加文本内容的打印文件检验具有直观、可靠的效果。     

Temperature fluctuations at sympathetic preganglionic neuron sites in the thoracolumbar section of the spinal column as cues to deception: a preliminary study

In this experiment, both thermal imaging and the Concealed Information Test (CIT) methodologies were adopted, for the first time, to explore the efficacy of the thermal imaging of the thoracolumbar (T1–L3) region of the spinal column within the context of deception detection. Thirty-one participants followed a CIT-based structured interview process in a low-stakes laboratory setting whereby temperature fluctuations induced by the preganglionic neurons in the spinal column were measured with a thermal imaging camera during verbal responses to interview questions. The degree of temperature changes was then analyzed in order to determine truthfulness and deceit. Thermal imaging of the thoracolumbar region of the spinal column during sympathetic activation was effective in determining truthful responses with an accuracy rate of 91.9% and deceitful responses with an accuracy rate of 71.0%. Current findings support the potential use of temperature fluctuations of preganglionic neuron sites in the thoracolumbar section for lie-detection purposes.     

Introducing 3D Printed Models as Demonstrative Evidence at Criminal Trials

This case report presents one of the first reported uses of a 3D printed exhibit in an English homicide trial, in which two defendants were accused of beating their victim to death. The investigation of this crime included a micro‐CT scan of the victim's skull, which assisted the pathologist to determine the circumstances of the assault, in particular regarding the number of assault weapons and perpetrators. The scan showed two distinct injury shapes, suggesting the use of either two weapons or a single weapon with geometrically distinct surfaces. It subsequently served as the basis for a 3D print, which was shown in court in one of the first examples that 3D printed physical models have been introduced as evidence in a criminal trial in the United Kingdom. This paper presents the decision‐making process of whether to use 3D printed evidence or not.