Observations and 3D Analysis of Controlled Cast-Off Stains

Cast-off stains are common patterns found at crime scenes involving blood shedding events. However, the analysis and interpretation of cast-off patterns remains an area lacking tools for crime scene investigators. Analyzing cast-off patterns may allow investigators to interpret the area from where an object may have been swung and thus determine the approximate location of a suspect or victim. This study looked at the position and distribution of cast-off patterns and area of origin as a starting point for the development of a method to analyze cast-off patterns. Through a series of tests using a controlled cast-off rig (n = 10), it was observed that a Path Volume Envelope (PVE) may be identified where the swinging path is contained in a volume along with an area of exclusion. The calculated center, linear position of the PVE was found to have an average error of just over 3.2 cm when compared to the known object swing path position. The maximum deviation of the PVE to the known swing path was found to be 5.0 cm with a standard deviation of 1.4 cm. Additional studies are required to investigate the effects of partial cast-off stains, wielded object velocity, direction of swing, distance from the projected surface, and other factors. The observations and analysis from this study were seen to be predictable and repeatable and may provide a possible new method for investigators to interpret cast-off stains.     

房屋拆迁补偿与公民财产权的宪法保护

房屋拆迁是对公民重大财产的剥夺,不仅涉及到公民财产所有权等民事权利的保护,更涉及到公民私有财产的宪法保护。我国宪法对公民财产权保护的制度性的不足,是导致房屋拆迁实践中种种问题的渊薮。尤其是此次修宪对“公共利益”的定义,和对征收、征用私有财产的补偿原则的缺失,使公民财产权利保护的原则在宪法层面上缺乏依据。在房屋拆迁方面,上述不足将公民房屋拆迁及其补偿造成至为不利的影响。因此,严格规制公共利益和公平补偿应当是对私有财产保护的宪法原则,也应当是房屋拆迁补偿中的核心原则。其中,拆迁补偿方式中, 原址产权调换在体现公平补偿原则方面具有特殊的重要意义。笔者认为,以原址产权调换为原则,来确定拆迁补偿方式或金额,并以此为房屋产权人户提供多种安置补偿方式,是当前解决拆迁纠纷的现实之举。     

农村财务委托代理制的积极效应及其障碍排除——以广东湛江农村财务委托代理模式为例

广东湛江探索实行的农村财务委托代理是一种行之有效的模式。农村财务委托代理制在规范农村财务管理、密切农村党群干群关系、促进农村经济健康稳步发展等方面产生了积极效应。在推行过程中,对于思想认识、法理支持、责任追究、代理操作以及可持续发展方面的障碍要予以排除。     

Vitality and age of conjunctival petechiae: The expression of P-selectin

Confocal laser scanning microscopy (CLSM) results in displaying multiple ruptures of capillaries and venules define conjunctival petechiae as a rhexis haemorrhage. In order to distinguish between petechiae which have arisen before death as opposed to post-mortem artefacts and the establishment of the age of the vessel's damage, we carried out an investigation on a collection of samples from medico-legal cases (positive petechiae: n = 65; post-mortem artefacts: n = 12; control: n = 19) to establish whether the expression of the endothelial adhesion molecule P-selectin as demonstrated by immunohistochemical methods is influenced by trauma before death and possibly by time. Except for cases with massive congestion in those cases where the victim had survived for around minutes, CLSM examination revealed a strong endothelial reaction at the site where the vessel had ruptured. It was impossible to detect a strong P-selectin expression signal in both those vessels which had not suffered any mechanical insult and those which had experienced post-mortem rupture. Therefore, the elevated expression of P-selectin can be used as a criterion to distinguish between those lesions which have occurred in life and those which are post-mortem artefacts.     

A Preliminary Study on Sources of Banding Artifacts for the Identification of Monochromatic Laser Printers,

The analysis of questioned documents printed with monochromatic toner has been a great challenge to document examiners. Banding artifacts, which are often perceived in the outputs of laser printers, could be a solution to the identification of printers. In this study, sources other than the gear transmission errors were discovered for some primary banding frequency components. By detecting the angular velocity variation of photosensitive drums and other rotating parts of the tested printers and comparing them with the banding signals extracted from the printouts, the authors located the sources of banding frequency components. It was shown that the sources of some primary and persistent banding signals, which were previously unknown, were traced to the periodic velocity variations of the motors or the timing belts. As inherent signatures, banding artifacts could be promising features for discriminating documents printed by individual laser printers.     

The Juvenile Justice Reform Act of 2018: Updating the Federal Approach to Youth Involved,and At‐Risk of Becoming Involved,in the Juvenile Justice System

On December 21, 2018, the Juvenile Justice Reform Act was signed into law, marking the first update in 16 years to the Juvenile Justice and Delinquency Prevention Act of 1974, as amended. The reforms reflect much of the knowledge that has been gained through research and science over the past decade and strengthen the Act’s core protections for youth in the juvenile justice system. The changes also expand the Office of Juvenile Justice and Delinquency Prevention’s role in research, and technical assistance, and provide for additional oversight for related programs.     

线聚焦显微激光拉曼光谱技术区分激光打印墨粉

目的利用Renishaw InVia激光显微拉曼光谱仪对打印墨粉进行区分。方法用785nm激发波长,采取线聚焦模式,50倍物镜条件下,测定了惠普等8个品牌25种硒鼓型号的30份激光打印机打印墨迹样品的拉曼光谱。结果 30种样品墨迹的谱图进行了分析,根据拉曼的异同,可将30种样品分为5大类。结论线聚焦显微激光拉曼光谱可用于区分不同种类激光打印墨粉。     

MALDI-TOF-IMS在蛋白质组学研究中的新进展

基质辅助激光解吸/电离-飞行时间质谱成像(matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry,MALDI-TOF-IMS)技术已成为目前蛋白质组学研究中的经典技术,是一种研究生物组织切片中蛋白质和小分子物质分布的工具。MALDI-TOF-IMS通过单次扫描就能够同时分析生物组织切片中的各种未知组分,在保持组织中细胞和分子完整性的同时获取组织的分子成像图。近年来,质谱成像技术在生物医学各领域中有了较快发展,本文综合文献资料对MALDI-TOF-IMS技术目前的发展水平、质谱成像原理、方法学以及在法医病理学中的应用前景进行了综述。     

Calculating Point of Origin of Blood Spatter Using Laser Scanning Technology

The point of origin of an impact pattern is important in establishing the chain of events in a bloodletting incident. In this study, the accuracy and reproducibility of the point of origin estimation using the FARO Scene software with the FARO Focus^3D laser scanner was determined. Five impact patterns were created for each of three combinations of distances from the floor (z) and the front wall (x). Fifteen spatters were created using a custom impact rig, scanned using the laser scanner, photographed using a DSLR camera, and processed using the Scene software. Overall results gave a SD = 3.49 cm (p < 0.0001) in the x‐direction, SD = 1.14 cm (p = 0.9291) in the y‐direction, and SD = 9.08 cm (p < 0.0115) in the z‐direction. The technique performs within literature ranges of accepted accuracy and reproducibility and is comparable to results reported for other virtual stringing software.