应用SME/EDX和ICP-AES检测元素成份判定致伤工具

目的应用扫描电镜／能谱联合分析仪(Scanning electron microscopy&Energy dispersive X-ray apparatus SEM／EDX)和电感耦合原子发射等离子光谱(inductively coupled plasma-atom emission spectrometer ICP-AES)对金属致伤工具本身及所致创口残留物元素成分分析，探讨两者在推断认定此类工具的应用条件及价值。方法镀层和普通铁质工具在乳猪皮肤各致创5例，SEM／EDX对创口内遗留金属颗粒元素检测；用标准样品检测实验方法的精确度；普通铁质工具于刀背、刀刃处各取5个样本，ICP-AES测定元素成分与含量。结果镀锌工具所致创口中存在单一含有锌的金属颗粒，镀黄铜工具则同时含有锌和铜，未发现其它元素；不锈钢或普通铁质菜刀创口中，发现同时含有铁、铬、硅或铁、锰、硅的颗粒；除5号菜刀外同一把铁质菜刀在刀刃、刀背处元素含量无明显差别；ICP-AES分析表明不锈钢菜刀之间在铬、锰、硅、铜、钼和5号刀背部以及其他铁质菜刀在锰、硅元素含量差别具有显著意义，5号刀刃部锰、硅、钼、钛、磷、硫、镍元素RSD明显升高。结论SEM／EDX可以通过创口的检测对金属致伤工具进行种类的推断认定，ICP-AES则可在同种类致伤工具中进行相对同一的判定有应用价值。     

应用SEM/EDX和ICP-AES检测元素成份判定致伤工具

目的应用扫描电镜/能谱联合分析仪(Scanning electron microscopy & Energy dispersive X-ray apparatus SEM/EDX)和电感耦合原子发射等离子光谱(inductively coupled plasma-atom emission spectrometer ICP-AES)对金属致伤工具本身及所致创口残留物元素成分分析,探讨两者在推断认定此类工具的应用条件及价值.方法镀层和普通铁质工具在乳猪皮肤各致创5例,SEM/EDX对创口内遗留金属颗粒元素检测;用标准样品检测实验方法的精确度;普通铁质工具于刀背、刀刃处各取5个样本,ICP-AES测定元素成分与含量.结果镀锌工具所致创口中存在单一含有锌的金属颗粒,镀黄铜工具则同时含有锌和铜,未发现其它元素;不锈钢或普通铁质菜刀创口中,发现同时含有铁、铬、硅或铁、锰、硅的颗粒;除5号菜刀外同一把铁质菜刀在刀刃、刀背处元素含量无明显差别;ICP-AES分析表明不锈钢菜刀之间在铬、锰、硅、铜、钼和5号刀背部以及其他铁质菜刀在锰、硅元素含量差别具有显著意义,5号刀刃部锰、硅、钼、钛、磷、硫、镍元素RSD明显升高.结论SEM/EDX可以通过创口的检测对金属致伤工具进行种类的推断认定,ICP-AES则可在同种类致伤工具中进行相对同一的判定有应用价值.     

骨砍创金属颗粒的检测

目的 应用扫描电镜/X射线能谱仪(SEM/EDX)对菜刀砍击骨质后遗留在创面上的金属微粒进行检测.方法 3种不同材质菜刀各取5把,对猪大腿骨进行砍击,使用SEM/EDX对骨创面上附着的金属颗粒元素以及菜刀自身所含元素进行定性及定量检验,并对结果进行比对分析.结果 菜刀样本同型号之间元素重量百分比相比较,结果无统计学差异(P＞0.05);创面附着金属颗粒与菜刀自身所含元素种类特征相同;其所占重量的百分比一致(P＞0.05);结论 骨骼创面遗留金属颗粒的元素种类及其百分比含量,可以作为区分菜刀类致伤工具的重要依据.     

机械性损伤的致伤物推断

致伤物推断是法医损伤鉴定中的重要内容,也是法医病理学家的重要研究领域。致伤物推断主要是从创口形态、创内残留物、附着物以及可疑致伤物上的附着物三个角度进行。目前随着多种先进检测方法在法医损伤鉴定中的相继应用,使得致伤物推断获得较大进展,受到国内外专家的关注,创口形态观察从宏观到微观,射击残留物的检测从无机成份到有机成份,从单一的成份分析到与形态学相结合。本文总结了近十年来国内外致伤物推断的研究方法与内容,旨在对该方面的研究进展进行总结,阐明研究的主要成果及存在的问题,为法医检案提供帮助。     

微痕量检验在致伤物推断与认定中的价值

致伤物可为侦查和审判提供准确、可靠的线索和证据。在法医学实践中，创内异物的分析与检测一直是致伤物推断和认定的重要途径之一。近年来，随着一系列先进检测技术的应用，使得致伤物在创周遗留的微痕量物证的发现和检验获得了重要进展。微痕量检验也由对火器伤射击残留物的分析扩展到钝器伤和锐器伤检验．并取得了初步的进展。     

Application of laser induced breakdown spectroscopy to examination of writing inks for forensic purposes

The research was focused on the analysis of writing inks using the laser induced breakdown spectroscopy (LIBS) technique. 34 samples of blue, 30 of black, and 21 of red writing inks were analyzed under optimized conditions to determine the variation of chemical composition of inks between different colours, brands and types. Nine elements (Ba, Cr, Cu, Fe, Li, Mo, Mn, Ni and W) were taken into account during comparative analysis of inks. Because of the strong effect of the paper spectrum, elements often found in inks (Ca, Al, Mg, Na, Ti, and Si) were eliminated from LIBS analysis of inks. It was determined that the LIBS method is capable of revealing qualitative elemental differences between ink samples. The discrimination power of this method was found to be 83, 82 and 61% for blue, black and red inks, respectively. Inks produced by the same producer were able to be differentiated in some cases. The results showed the potential of LIBS for forensic purposes as an effective and robust technique, requiring a small amount of sample and giving analytical information in a very short time.     

腰椎间盘突出的自身免疫反应及其法医学意义

损伤时间推定与伤、病鉴别,一直是法医学领域研究的重要课题。腰椎间盘突出是一种以人的生理退行性变为基础的改变,为了寻找准确推断其发生时间的方法,本文综述了腰椎间盘突出后机体细胞免疫、体液免疫反应与损伤时间的关系。认为进一步研究突出髓核组织局部与外周循环中IgG、IgM表达的特征性变化,有望成为推定损伤时间的方法之一。     

Quantitative analysis of sharp-force trauma: an application of scanning electron microscopy in forensic anthropology.

Scanning electron microscopy (SEM) has occasionally been used by anthropologists and forensic scientists to look at morphological characteristics that certain implements leave on bone. However, few studies have addressed techniques or protocols for assessing quantitative differences between tool marks on bone made by different bladed implements. In this study, the statistical variation in cut mark width was examined between control and test samples on bone using a scalpel blade, paring knife, and kitchen utility knife. Statistically significant differences (p < .0005) were found between cut marks made by the same knife under control and test conditions for all three knife types used in the study. When the control sample and test samples were examined individually for differences in mean variation between knife types, significant differences were also found (p < .0005). While significant differences in cut mark width were found, caution should be used in trying to classify individual cut marks as being inflicted by a particular implement, due to the overlap in cut mark width that exists between different knife types. When combined, both quantitative and qualitative analyses of cut marks should prove to be more useful in trying to identify a suspect weapon. Furthermore, the application of SEM can be particularly useful for assessing many of these features.     

Gunshot residue testing in suicides: Part II: Analysis by inductive coupled plasma-atomic emission spectrometry

Several different methods can be employed to test for gunshot residue (GSR) on a decedent's hands, including scanning electron microscopy with energy dispersive x-ray (SEM/EDX) and inductive coupled plasma-atomic emission spectrometry (ICP-AES). In part I of this 2-part series, GSR results performed by SEM/EDX in undisputed cases of suicidal handgun wounds were studied. In part II, the same population was studied, deceased persons with undisputed suicidal handgun wounds, but GSR testing was performed using ICP-AES. A total of 102 cases were studied and analyzed for caliber of weapon, proximity of wound, and the results of the GSR testing. This study found that 50% of cases where the deceased was known to have fired a handgun immediately prior to death had positive GSR results by ICP/AES, which did not differ from the results of GSR testing by SEM/EDX. Since only 50% of cases where the person is known to have fired a weapon were positive for GSR by either method, this test should not be relied upon to determine whether someone has discharged a firearm and is not useful as a determining factor of whether or not a wound is self-inflicted or non-self-inflicted. While a positive GSR result may be of use, a negative result is not helpful in the medical examiner setting as a negative result indicates that either a person fired a weapon prior to death or a person did not fire a weapon prior to death.     

An unusual death by transcranial stab wound: homicide or suicide?

Penetrating stab wounds of the brain are uncommonly seen in modern times and occur almost exclusively in homicides. We report an unusual death by self-stabbing. A 24-year-old man was found dead at home, the handle of a kitchen knife protruding from his forehead. Data such as the psychiatric history of the victim, the multiplicity and site of wounds, the implement used, the presence of hesitation, and defense wounds were studied to elucidate the manner of death, and the suicidal nature of the event was established after police investigation. Atypical injuries require a careful forensic investigation, and medico-legal aspects of the differentiation between homicide and suicide are discussed in this particular case. A review of the literature revealed few cases of suicidal transcranial stab wounds.     

Suicidal Decapitation by Guillotine: Case Report and Review of the Literature

Abstract: Suicidal decapitation is seldom encountered in forensic medicine practice. This study reports the analysis of a suicide committed by a 31‐year‐old man with a self‐fabricated guillotine. The construction of the guillotine was very interesting and sophisticated. The guillotine‐like blade with additional weight was placed in a large metal frame. The movement of the blade was controlled by the frame rails. The steel blade was triggered by a tensioned rubber band after releasing the safety catch. The cause of death was immediate exsanguination after complete severance of the neck. The suicide motive was most likely emotional distress after the death of his father. In medico‐legal literature, there has been only one similar case of suicidal complete decapitation by a guillotine described.     

SEM/EDAX检测内脏异物元素成分诊断溺死

为探讨溺死诊断的依据和推断入水地点，用扫描电镜／X－射线谱仪（SEM／EDAX）检测19例溺死尸体及28只溺死兔的肺、肾、心、肝等组织异物颗粒及其元素成分和含量，并以陆地上死亡尸体14具及8只陆地上勒死兔（2只勒死后入水浸泡6天）作实验对照。结果发现，19例溺死尸体及28只溺死兔的肺边缘区呼吸性细支气管、肺泡管、肺泡囊及肺泡内均可见高能谱值的异物颗粒，其大小自数微米至数十微米不等，多为无定形异物颗粒或细小异物颗粒集落。其中元素成分为硅、铝、钙、铁、铬、钛、钼、铅、锡、铜、溴等，与入水地点溺液中所含元素成分相同；肾、心、肝组织异物颗粒检出率分别为77％、53％及47％，数量较少，颗粒较小，大小自1微米以下至十数微米。非溺死尸体及实验兔的肺、肾、心、肝组织未检出或偶尔检出异物颗粒，其元素成分多为铁、钙或硅等，可能是病理及生理性异物颗粒，如含铁血黄素、钙化灶等。用SEM／EDAX检测水中尸体组织中异物颗粒及其元素成分和含量，可以诊断溺死，推断入水区域，为明确案件性质和确定侦察范围提供科学依据。     

Puncture wounds caused by glass mistaken for with stab wounds with a knife

Three cases are presented where fatal puncture wounds caused by broken glass were very similar to stab wounds inflicted by a knife with a single-edged blade. Thus, all three cases caused a murder investigation to be initiated. It could only be determined that these wounds had been caused by glass after a detailed forensic autopsy. In two of the three cases, the only evidence for this was the identification of glass fragments in the wounds. The importance of X-ray examinations is underlined because modern glass in common use is radiopaque. Glass fragments lodged in the wounds can reduce the loss of blood and thus, prolong the capacity to act despite severe injuries.     

Sharp Force Homicide in Denmark 1992–2016

Sharp force trauma is a common homicide method. The weapon is typically a knife, which is easily accessible and does not require special skills. We have analyzed all 471 sharp force homicides in Denmark during 1992–2016 with special focus on aspects that are relevant to forensic pathologists, including the distribution of wounds and organ injuries. Most homicides were committed inside with a kitchen knife. The front left thorax was the most common area to be affected by sharp force trauma. In 18.9% of the victims, there was only one sharp injury, the majority on the thorax. The most common trajectory for stab wounds was directly posterior with no deviation to the sides or up/down followed by directly anterior. The heart (including pericardium) and lungs (including hemo- and pneumothorax) had injuries in more than 75% of the victims. 67% of victims were males. Female victims had more sharp force injuries and defense wounds than male victims. Most females were killed in domestic homicides (73.7%), most commonly in partner killings (56.4%). In contrast, many male victims were killed in a setting of nightlife/intoxication (34.0%) most by a friend/acquaintance delivering a few stab wounds. The results clearly show strong sex differences in both victims and offenders. This could be useful for shaping policies and public opinion, and as a route for understanding the developments in interpersonal violence. In the narrow setting of death investigation, our results will provide an evidence-based approach to understanding the injury patterns in sharp force homicide.     

Injury pattern on the hand after slipping onto the blade during a knife attack--a contribution to the differential diagnostic classification of sharp force injuries of the upper extremities

Differential diagnosis of injuries caused by accidental slipping of the hand onto the blade of a knife includes self-inflicted injuries (e.g. to simulate an offense) as well as active and passive defense injuries indicative of the involvement of another party. The injury pattern on the hands of five perpetrators who suffered accidental cuts during knife attacks, as seen by the authors during the clinical forensic examination, is presented. The injuries were localized on the ulnar aspect of the thumb facing the index finger, the radial aspect of the index finger facing the thumb and variable sites on the flexor or extensor side of the middle and ring fingers. Especially in those cases in which the injuries of the victim (e.g. involvement of bony structures) and the dominant hand of the perpetrator are known, additional information for the reconstruction of the course of events may be derived from the cut wounds occurring during the knife attack as the hand slipped onto the blade.     

扫描电镜/X射线能谱仪检验电流斑规范化方法探讨

目的探讨电流斑皮肤金属化的机理、检材提取处理和扫描电镜/能谱仪检验规范化方法,对检验结果进行分析和价值判断。方法用扫描电镜/能谱检验,采用低倍大窗口覆盖损伤区域采集平均元素能谱图,并在可能的金属元素富集区域寻找球形金属颗粒。结果扫描电镜下可观察到散在的孔穴、细胞碎屑、龟裂、裂隙等特征,有些电流斑可检出金属元素,其中部分电流斑可发现球形金属颗粒。结论采用规范化的检材提取、处理和检验方法可消除随意性方法造成错检的可能。电流斑皮肤上异常含量的金属附着可支持病理检验符合电流斑表现的结论,同时也为电击导体的推断和金属元素成分比对提供依据。球形金属颗粒的发现揭示存在电弧高温的可能性极大,可强力支持病理检验符合电流斑表现的结论。     

胸部损伤死因鉴定审查在诉讼中的应用

人身伤害案件被害人的死因鉴定,轻则涉及被告人的量刑,重则事关案件的定性。而司法实践中,经常遇到一些刑事被害人的死因鉴定意见是建立在推断的基础之上,且其推断不具有排他性,经不起推敲,往往直接影响到案件的定性与处理。针对这一问题,结合司法案例进行分析,以期提升死因鉴定的证明力和法医学鉴定意见的公信力。     

Bumping into a knife--exculpatory statement or (tragic) accident?

Assessing stab wounds is a common task in forensic medicine. Quite often an accused claims that the victim bumped into the knife. Taking into account all the facts ascertained in the investigations conducted, such a statement can be rapidly disproved in most cases. The present case of a 14-year-old boy fatally wounded by his mother with a kitchen knife examines the aspect of walking into a knife. It is an example that this statement cannot always be regarded as implausible and that every single case has to be reconstructed in detail on the basis of all the investigation results.     

电感耦合等离子体质谱法检测电流损伤皮肤中金属元素

目的探讨应用电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)技术检测电流损伤皮肤中金属元素的可行性,建立检测电流损伤皮肤中金属元素的方法。方法用黄铜、紫铜、铝、铁电极材料以220V交流电电击家兔后肢,ICP-MS对电流损伤皮肤中金属元素进行检测。结果与对照组比较:黄铜电击组皮肤中的Cr、Ni、Cu、Zn、Pb含量升高(P0.05),紫铜电击组皮肤中的Cr、Cu、Pb含量升高(P0.05),铝电击组皮肤中的Al、Cr、Mn、Co、Ni、Cu、Pb含量升高(P0.05),铁电击组皮肤中的Cr、Mn、Fe、Ni含量升高(P0.05)。不同电极材料电击后皮肤中元素种类及含量也存在明显差异。结论ICP-MS可作为检测电流损伤皮肤中金属元素的有效方法,且可应用于触电材料的推断。     

Lethal head injury due to tear-gas cartridge gunshots

We report a fatal head injury caused by a tear-gas cartridge and point out the underestimated potential injury of this type of weapon. Gas pressure wounds and the death mechanisms are also described. A review of the literature and forensic considerations of head injury without projectile are presented.