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901.
Sudden cardiac death (SCD) is one of the most common causes of death. An important number of sudden deaths, especially in the young, are due to genetic heart disorders, both with structural and arrhythmogenic abnormalities. In recent years, significant advances have been made in understanding the genetic basis of SCD. Identification of the genetic causes of sudden death is important because close relatives are also at potential risk of having a fatal cardiac condition. A comprehensive post-mortem investigation is vital to determine the cause and manner of death and provides the opportunity to assess the potential risk to the family after appropriate genetic counselling. In this paper, we present an update of the different genetic causes of sudden death, emphasizing their importance for the forensic pathologist due to his relevant role in the diagnosis and prevention of SCD.  相似文献   
902.
Taphonomy is the study of many variables involving decomposition, preservation, dispersal, erosion, burial or exposition of dead organisms. Forensic Taphonomy examines how biotic or abiotic variables can change evidences in legal investigations. Many insects are closely associated with decomposition processes. The scavenger dung-beetle, Coprophanaeus lancifer (Linnaeus, 1767), may be important biotaphonomically in the decomposition process of carcasses. Man-size pig carcasses were used as models to examine the decomposition process in the Adolpho Ducke Forest Reserve in central Amazonia. The scavenger dung-beetle has great potential in decomposition and production of post-mortem injuries, including dismemberment and the removal of soil beneath the carcass thereby causing a change in its position.  相似文献   
903.
A simultaneous analytical method for etizolam and its main metabolites (alpha-hydroxyetizolam and 8-hydroxyetizolam) in whole blood was developed using solid-phase extraction, TMS derivatization and ion trap gas chromatography tandem mass spectrometry (GC-MS/MS). Separation of etizolam, TMS derivatives of alpha-hydroxyetizolam and 8-hydroxyetizolam and fludiazepam as internal standard was performed within about 17 min. The inter-day precision evaluated at the concentration of 50 ng/mL etizolam, alpha-hydroxyetizolam and 8-hydroxyetizolam was evaluated 8.6, 6.4 and 8.0% respectively. Linearity occurred over the range in 5-50 ng/mL. This method is satisfactory for clinical and forensic purposes. This method was applied to two unnatural death cases suspected to involve etizolam. Etizolam and its two metabolites were detected in these cases.  相似文献   
904.
Forensic psychiatric reports on 166 sexual homicide perpetrators in Germany were retrospectively analyzed for criminal risk factors. Follow-up information about release and reconvictions from federal criminal records was available for 139 offenders; 90 (64.7%) had been released. The estimated recidivism rate (Kaplan-Meier analyses) for 20 years at risk was 23.1% for sexual and 18.3% for nonsexual violent reoffences. Three men (3.3%) were reconvicted for attempted or completed homicide. Only young age at the time of sexual homicide resulted in higher sexual recidivism, whereas increased nonsexual violent recidivism was related to previous sexual and nonsexual delinquency, psychopathic symptoms, and higher scores in risk assessment instruments. Increased recidivism with any violent reoffence was associated with age-related factors: young age at first sexual offence, at homicide, and at release and duration of detention. The impacts of the results for risk assessment, relapse prevention, and supervision are discussed.  相似文献   
905.
Research consistently illustrates that several intellectual disabilities--namely, learning disabilities (LD), low intelligence, challenging behavior, and inadequate adaptive behavior, as well as attention deficit hyperactivity disorder (ADHD)--are considered risk factors for antisocial and criminal behavior. Although much attention has been paid to the relationship of LD, ADHD, and criminal behavior, three research topics have been overlooked: the frequency of LD with ADHD among inmates, the relationship between LD and/or ADHD and level of education among prisoners, and the connection between LD and/or ADHD and age of criminal onset. The present study examined the frequency of LD and ADHD in a sample of Israeli-born prisoners, in addition to the frequency of each category by itself, and it investigated the relationship of LD and/or ADHD, school dropout age, and onset of criminal activity.  相似文献   
906.
In criminal proceedings involving illegally manufactured substances, evidence demonstrating the manufacture is required for successful prosecution. In many circumstances the presence of manufacturing equipment and 'recipes' are clear indicators. However establishing chemical links between starting materials and products would be beneficial additional evidence in such circumstances. Isotope analysis is becoming more commonly employed in disputes over authenticity and provenance of materials such as food stuffs or pharmaceuticals [S. Benson, C. Lennard, P. Maynard, C. Roux, Forensic applications of isotope ratio mass spectrometry--a review, Forensic Sci. Int., 157 (2006) 1-22]. We report here the results of an isotope study investigating a link between hexamine used as a starting material and the product explosive RDX, manufactured using the Woolwich process. Isotopic composition of hexamine and RDX was analysed by stable isotope ratio mass spectrometry. Five different hexamine samples were selected from a group of eleven for use in this study. One of the five hexamine samples was used twice, providing data on the reproducibility of the synthesis. Carbon and nitrogen isotope analysis of the hexamine starting material and RDX products reveals a reproducible relationship between reactant and product.  相似文献   
907.
Adipocere formation is well known as a later post-mortem change. We experienced a female victim who had been sealed up in a clothes box for approximately 4 years. We collected several subcutaneous fats as well as visceral fats from the victim to investigate adipocere formation. Fresh subcutaneous fats of one female and five male victims who suddenly died were used as the control. These samples were homogenized and the lipids were extracted with chloroform and methanol followed by injection into gas chromatography-mass spectrometry and gas chromatography. We detected a hydroxy fatty acid in the fat of the case, but not in the controls. Using standard synthetic hydroxy fatty acid, the lipid extract component was identified as 10-hydroxyoctadecanoic acid (10-OH 18:0) and this concentration was quantified. Consequently we confirmed that adipocere was formed much slowly in dry concealment. In addition, the fatty acid composition was compared with the control. Most of the linoleic acid (18:2) disappeared and a peak developed instead. Using standard synthetic fatty acid, this peak was identified as cis-12-octadecenoic acid (cis-12-18:1). This suggests that linoleic acid is hydrogenated to cis-12-octadecenoic acid in the process of adipocere formation.  相似文献   
908.
Two groups were selected from the remainder of hair samples that had been tested for drugs at TrichoTech for medico-legal cases: samples that tested negative (drug-negative group; N=42, age 33.4+/-7.2 years) and samples that tested positive for drugs (drug-positive group; N=57, age 32.5+/-8.8 years). A rapid, simple method to detect the ethanol metabolite, ethyl glucuronide (EtG) in hair has been developed. The hair samples were sectioned, and then submitted to overnight sonication in water. Samples then underwent SPE using anion exchange cartridges, followed by derivatisation with N,O-bis[trimethylsilyl]trifluoroacetamide (BSTFA), before confirmation by GC-MS/MS. The assay produced excellent linearity and sensitivity over the calibration range 0.02-1.0 ng/mg, assuming a 10 mg hair sample. The mean age of the two groups was not statistically different (p=0.575, Student t-test), indicating a homogeneous group. Twelve of the 57 (21.0%) hair samples of the drug-positive group tested positive for EtG, and 17 of the 42 (40.5%) hair samples of the drug-negative group tested positive for EtG. The mean concentration of EtG in the drug-positive group was 0.011 ng/mg compared to 0.107 ng/mg in the drug-negative group. When the full results of this study were subjected to statistical analysis it was shown that EtG levels in the drug-negative group were statistically higher than those found in the drug-positive group (p<0.05). This preliminary finding may be of use in the study of addiction and adds valuable data to previous studies regarding the use of EtG as a valuable marker for alcohol levels in hair.  相似文献   
909.
The aim of the present study was to compare the accuracy, precision, and bias of two macroscopic and one histological age at death estimation methods on human teeth. The sample was comprised of 67 permanent teeth, obtained from 37 individuals aged 20-91 years. Age was predicted according to the methods proposed by Lamendin et al. (LAM), Bang and Ramm (BR), and the quantification of tooth cementum annulations (TCA). TCA was found to be most accurate in all age groups. Its mean absolute error of the estimated age was about half as high as the mean absolute error for both LAM and BR. BR achieved approximately the same mean absolute error as TCA for old adults only. LAM displayed the highest precision in the young and the old age group whereas TCA was more precise in the middle age group. TCA was found to be the most precise method when the precision was calculated for all ages. Considering the bias, all methods displayed a tendency to overestimate age in young and to underestimate it in old specimens. The exception to this rule was TCA, which provided unbiased estimates for young adults. The higher accuracy and precision recommends favouring TCA over LAM and BR, provided that the required know-how and equipment are available.  相似文献   
910.
This case series documents and examines the association between autoerotic asphyxiation, sadomasochism, and serial sexual murderers. Autoerotic asphyxiation, along with other paraphilias found in this population, is reviewed. Five cases of serial sexual killers who engaged in autoerotic asphyxiation were identified worldwide: four from the United States and one from Russia. Case reports for each are provided. All (100%) were found to have sexual sadism in addition to autoerotic asphyxiation. Furthermore, two (40%) had bondage fetishism, and two (40%) had transvestic fetishism, consistent with these paraphilias co-occurring in those with autoerotic asphyxiation. Overall the group averaged 4.0 lifetime paraphilias. Some possible relationships were observed between the offenders' paraphilic orientation and their modus operandi, e.g., all of these serial killers strangled victims-suggesting an association between their sadistic and asphyxiative paraphilic interests. The overlap of seemingly polar opposite paraphilias in this sample--sexual sadism and autoerotic asphyxiation--is explored from a historical and clinical perspective. Multiple commonalities shared between these five offenders and serial sexual murderers in general are addressed. A primary limitation of this study is its small sample size and empirical basis; the results may not be generalizable beyond the sample. The findings from this study support the supposition that crime scene behaviors often reflect paraphilic disturbances in those who commit serial sexual homicides.  相似文献   
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