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421.
Microscopic characteristics of hacking trauma   总被引:1,自引:0,他引:1  
The purpose of this study was to determine if it is possible to associate machetes, axes, and cleavers with the microscopic parallel striations they leave on the cut surfaces of the bone. Hacking trauma was experimentally inflicted on pig bones using machetes, axes, and cleavers. Negative impressions of both the cut surfaces of the bone and the weapon blades were analyzed using scanning electron microscopy. The results of this investigation indicate that it is possible to correlate a class of hacking weapons to trauma inflicted on bone by these weapons.  相似文献   
422.
423.
This study examined the influence of closed-circuit television (CCTV) on jurors' abilities to detect deception in children's testimony. Children ages 7–9 individually played games and made a video movie with a male confederate. In the guilty condition, stickers were placed on exposed body parts (i.e., the child's arm, toes, and bellybutton). In the not-guilty and deception conditions, stickers were placed on the child's clothing rather than on bare skin. Approximately 3 weeks later, mock jurors recruited from the community viewed child participants testify either in a traditional courtroom setting or via one-way CCTV. The mock jurors responded to questions about the child witness and the defendant as well as deliberated to reach a verdict. Children in the deception condition were asked to testify as if the stickers had been placed on exposed body parts rather than on their clothing. Predeliberation, jurors were less likely to convict when a child testified in the deception condition as opposed to the guilty condition. These differences disappeared following deliberation. There was no support for the notion that jurors reach the truth better when children testify in open court versus via CCTV. Implications for jurors' abilities to reach the truth are discussed.  相似文献   
424.
Carbon monoxide (CO) poisoning typically causes so-called cherry-red livor of the skin and viscera. The authors report a case of CO poisoning in which cherry-red livor did not develop. The decedent was a 75-year-old white man who was found dead in his car during a cold winter. Blood CO saturation was 86%. The death was attributed to CO poisoning, and the manner of death was designated suicide. The curious absence of cherry-red livor was studied. The decedent's tissue and blood specimens were tested at different temperatures. There was no tendency for either type of specimen to develop cherry-red color at cold or warm temperatures. The antemortem response of the skin to cold possibly sequestered CO-saturated blood in the cadaver. As regards the viscera, there are other proteins to which CO can bond, and possibly these proteins contribute to the development of visceral cherry-red livor. In this case, the absence of cherry-red livor could have led to misclassification of the cause and manner of death. The medicolegal and social consequences of such misclassification can be significant, and psychiatric history, which may be useful to surviving family members, could be lost.  相似文献   
425.
Fetal death has been defined by the World Health Organization as death before complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy. Certain causes of fetal death, including syphilis, Rh isoimmunization, toxemia, and diabetes, have shown significant declines over the past several decades. However, many fetal losses continue to occur from intrauterine infections, lethal malformations, fetal growth retardation, and abruptio placentae. Fetal death with no identifiable specific cause is another consideration when dealing with these cases. Other risk factors can include maternal, sociodemographic, and medical care factors. The authors reviewed all forensic cases referred for autopsy to the Forensic Section of the Medical University of South Carolina, Medical Examiners' Office over the 10-year period 1990-1999. All cases listed as fetal death or stillbirth were included. The 42 cases were analyzed as to fetus' gestational age, sex, race, weight, location of delivery, history of prenatal care, maternal drug use, chromosomal abnormalities, cause and manner of death, and autopsy findings. The black:white ratio was approximately 2:1, and the male:female ratio was virtually 1:1. Most fetuses were older than 20 weeks' gestational age, with one third between 20 and 29 weeks. The majority were externally normal aside from maceration. Only 7.5% had congenital anomalies. Twenty-one of 38 placentas were grossly and microscopically normal. Of cases with toxicologic analysis, 21% were positive for drugs, and 17% were positive for cocaine/benzoylecgonine. The manner of death was classified as natural (28), accident (2), and undetermined (12). Few studies have reported the specific causes of fetal death, and the lack of uniformity in data collection and classification of causes of fetal death has made comparisons difficult. The authors present this retrospective study to better determine the factors leading to fetal demise in the hope of assisting death investigators in this challenging arena.  相似文献   
426.
Posttraumatic thrombosis of the middle cerebral artery   总被引:6,自引:0,他引:6  
Posttraumatic cerebral infarction resulting from carotid or cerebral artery occlusion is rare. Traumatic dissection of the carotid artery is the most frequent cause of infarction, whereas posttraumatic thrombosis of the cerebral artery is very rare. The authors describe a case of posttraumatic thrombosis of the left middle cerebral artery. Early in the morning, a 16-year-old boy was found unconscious in the parking lot of a supermarket. He had received fist blows and kicks to the head, face, body, back, and hip during the night. Computed tomography 10 hours after the violence revealed a gross cerebral infarction in the area of the left middle cerebral artery. He died 9 days after the violence. The autopsy revealed a thrombosis in the left middle cerebral artery. Microscopically, granulation tissue in the intima and a rupture of the internal elastic lamina were observed near the beginning of the artery. It was concluded that the blows to the head and face caused a partial rupture in the arterial wall, leading to thrombosis and cerebral infarction.  相似文献   
427.
428.
The aim of this work is to prove the application of craniometry in determining the identity of unknown bodies. There is a great correlation between the viscero-cranium appearance and the osseous structure, the said correlation following mathematical rules and thus being possible to be calculated. Various segments of the skull and different size of the angles they make with each other are directly responsible for the graphic profile of viscero-cranium. The nasal bones and their angle are the basis to determine the shape and size of the nose.  相似文献   
429.
To evaluate pathophysiological significance of post-mortem urinary myoglobin levels in determining the cause of death, we investigated 210 forensic autopsy cases, partially in comparison with serum levels. Post-mortem serum myoglobin levels were extraordinary high in most cases possibly due to post-mortem change. Urinary myoglobin levels did not correlate with the serum levels, showing possible post-mortem elevation in cases of a prolonged post-mortem period over 48h. A high (>1000 ng/ml), moderate (100-1000 ng/ml), slight (50-100 ng/ml) and not significant (<50 ng/ml) elevation of urinary myoglobin were observed in 26, 43, 31 and 110 cases, respectively. Half the highly elevated cases were those with a survival time over 24h. In cases of minor muscle injury such as head trauma, elevation of urinary myoglobin level was closely related to longer survival. In acute/subacute deaths with a post-mortem interval within 48h, a significant difference was observed in relation to the blood carboxyhemoglobin (COHb) levels of fire victims: myoglobinuria over 100 ng/ml was more frequently and markedly observed in cases with COHb below 60% than over 60%, suggesting muscle damage in fatal burns. Similar elevation was observed in heat stroke victims, and also in some cases of acute and subacute death from polytrauma, asphyxiation, drowning, electricity and spontaneous cerebral bleeding, but not in myocardial infarction. Thus, it was suggested that high post-mortem urinary myoglobin levels in acute and subacute death cases may be a possible indicator of antemortem massive skeletal muscle damage as well as exertional muscle hyperactivity or convulsive disorders associated with hypoxia.  相似文献   
430.
From 1984 to 1990. Congress enacted a series of mandates that expanded Medicaid eligibility for low-income children by gradually delinking Medicaid eligibility from welfare eligibility. The 1996 national welfare reform law nominally completed the delinking process when the statutory phase-in of children's Medicaid coverage was preserved even as the states were given increased flexibility for administering welfare programs. This article provides estimates of the impact of these fedcral policy changes on children's Medicaid enrollment rates and analyzes the degree of success in uncoupling children's Medicaid enrollment from welfare. Data from the Current Population Survey for 1979 to 1998 are used to provide standardized enrollment probabilities for the United States and individual states. The results show important enrollment increases associated with the period of the mandated expansions, followed by enrollment declines associated with welfare reform. The largest increases in enrollment during this period were in states with historically restrictive welfare eligibility, but rates also rose in states that previously had relatively expansive welfare eligibility. The net effect was a reduction in the extent of state-to-state variation in enrollment. The Medicaid expansion peaked in 1995, prior to the advent of national welfare reform. Since then, children's Medicaid enrollment has fallen, with the largest declines falling on families with the very lowest incomes. Consistent with the desire to delink children's Medicaid coverage from welfare, the association between Medicaid and AFDC/TANF enrollment weakened during the expansionary period, but there still was a relatively strong relationship between policy outcomes for these two programs. Despite the policy changes, Medicaid coverage of children is still influenced by state-level welfare policy.  相似文献   
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