撬压痕迹的力学分析与计算

本文应用力学的理论、观点和方法,对撬压痕迹的本质、受破坏的客体对外力作用的抵抗表现进行分析,并归纳各种常见客体的结构形式、功能特点和痕迹形成的规律,为办案实践中的具体对象制定了分析问题和解决问题的方法。     

A Morphological and Morphometric Study of Bite Marks Caused by Mice (Mus Musculus) on Different Baits for Forensic Purposes

In animal bites, the dental attributes can be fundamental in identifying the marks made by various species on different matrices. Although rodent bite marks have been studied in the context of postmortem interference, little research has used different baits to analyze these marks linking not only specific behavior patterns but also the possibility of structural damage. Twenty mice (Mus musculus) were exposed to different baits to study their bite marks in a controlled model. The known pattern of parallel and multiple grooves has been seen in all baits, but polyvinyl chloride and fiber‐optic cable were significantly different between each other and the other baits. Some baits showed patterns of anchorage of the upper incisors and space between the lower incisors when gnawing. This technical note represents a novel model of analysis where veterinarians and/or dentists may be asked to give an opinion on alleged animal bite marks.     

A technique to capture, analyze, and quantify anterior teeth rotations for application in court cases involving tooth marks

Anterior teeth within the human dentition have a specific numerical rotation value. Bite marks show an array of angled indentations, abrasions, microlacerations, and contusions. These marks generally represent the incisal surfaces of the suspect's dentition reflecting the rotation values of the teeth in the dental arch. This study described a method for capturing and analyzing anterior dental rotations. The rotations of individual anterior teeth within the study population were categorized as common, uncommon, and very uncommon according to Allen's classification. In the absence of a large number of incisal patterns present in a bite mark, a single but heavily weighted tooth rotation could be of equal discriminatory potential to several common rotation values. No prevalence studies quantifying individual tooth rotations are available. The measurement of each individual tooth rotation together with its individual discrimination potential will enhance the evaluation of the concordant features observed in bite marks.     

Reliability in age determination by pulp/tooth ratio in upper canines in skeletal remains

Estimation of age of skeletal remains is one of the most complex questions for anthropologists. The most common macroscopic methods are based on dental wear and histological evaluation of bone remodeling. These methods are often qualitative, require great technical expertise, and have proved inexact in the estimation of ages over 50 years. Certain dental methods investigate the apposition of secondary dentine, in the study of tooth cross-sections, and X-rays to study width, height, and pulp area. The primary author previously proposed a method of estimating the age of a living person based on the pulp/tooth ratio (PTR) method in the upper canines. The aim of the present study is to verify whether the PTR method can also be used to estimate the age at death of skeletal remains. This paper investigates the study of historical samples of known age as a means to validate the proposed method.     

浅析当前抢劫、抢夺犯罪行为之特征

当前,发生在我国的抢劫、抢夺犯罪相对突出,不仅牵扯着公安机关的精力,而且人民群众颇具微词反映强烈。这既有社会发展的客观情况,也有深层次的社会问题。本文力求从客观实际出发,深刻剖析"两抢"犯罪行为之特征,为打击、预防"两抢"犯罪的实践服务,从而达到有效遏制犯罪、维护良好社会治安秩序的目的。     

An Unusual Case of Predation: Dog Pack or Cougar Attack?

Injuries produced by animals are capable of leaving severe patterns and in some cases may result in the death of the attacked individual. Law enforcement authorities may come to erroneous conclusions about the source of the bites based on their awareness of animals present and similarities of the injuries to the untrained eye, with dreadful consequences. Expertise of a carnivore biologist and an odontologist that indentifies the particularities of bite marks may be useful for identifying the attacking species. We present the investigation of a fatal dog pack attack involving a 43‐year‐old man in Bell Ville (Argentina) where the evidence provided by a forensic dentist and a biologist was categorical for establishing the animal species involved. Because of the unusual characteristics of the wounds and the initial hypothesis made by local authorities of a cougar attack, habits and specific patterns of both dog pack and cougar predation on humans are discussed.     

盲摸器开启轿车用弹片锁形成痕迹的研究

目的研究盲摸器开启轿车用弹片锁形成的痕迹。方法解剖盲摸器开启的弹片锁后,观察比对弹片上痕迹位置和形态。结果4s店购买的锁具较小商品市场购买的锁具不易形成痕迹;经验丰富的开锁人员较经验少的开锁人员不易形成痕迹;盲摸器二较盲摸器一不易形成痕迹。结论盲摸器开启汽车锁形成的痕迹与锁具材质、开锁人员及工具形态有关。     

79式微型冲锋枪子弹射击顺序的研究

目的研究79式微型冲锋枪发射子弹的排序。方法对已知顺序实弹射击取样,扩大观察弹头、弹壳上发射过程中形成的痕迹,通过统计、归纳,从中发现与排序有关的痕迹特征。结果壳体肩部圆点痕,弹底边缘压擦痕、拉壳钩痕与发射顺序有关。结论壳体肩部圆点痕、弹底边缘压擦痕等痕迹的有无、位置及轻重程度,对判断79式微型冲锋枪弹壳发射顺序有较可靠的参考价值。     

Studies of the chronological course of wisdom tooth eruption in a Black African population

The importance of forensic age estimation in living subjects has grown over the last few years. In dental age estimation, tooth eruption is a parameter of developmental morphology that can be analyzed by either clinical examination or by evaluation of dental X-rays. In the present study, we determined the stage of wisdom tooth eruption in 410 male and 106 female Black South African subjects of known age (12-26 years) based on radiological evidence from 516 conventional orthopantomograms. Four eruption stages were determined (no emergence, alveolar emergence, gingival emergence, complete emergence). Statistical scores were determined for the individual stages separately for both sexes. The data presented here can be utilized for forensic estimation of the minimum and most probable ages of investigated persons.     

The analysis of tire rubber traces collected after braking incidents using Pyrolysis-GasChromatography/Mass Spectrometry

Automobile tire marks can routinely be found at the scenes of crime, particularly hit-and-run accidents and are left on road surfaces because of sudden braking or the wheels spinning. The tire marks are left due to the friction between the tire rubber and the solid road surface, and do not always demonstrate the tire tread pattern. However, the tire mark will contain traces of the tire. In this study, Pyrolysis Gas Chromatography/Mass Spectrometry was used to analyze 12 tires from different manufacturer's and their traces collected after braking incidents. Tire marks were left on a conglomerate road surface with sudden braking. The samples were pyrolysed without removal of contaminant in a micro-furnace type pyrolyser. Quantitative and qualitative analysis were performed on all the samples. All 12 samples were distinguished from each other. Each of the tire traces were identified as coming from there original source.