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901.
Elevated morphine concentrations determined during infant death investigations: artifacts of withdrawal of care 总被引:1,自引:1,他引:0
Abstract: Three cases are reported of elevated postmortem blood morphine concentrations (189–3036 ng/mL) that were observed during the course of death investigations involving three children ranging in age from 1 week to 2 years, all of whom underwent withdrawal of life support. In all three cases, the presence of opiates in postmortem blood was indicated by immunoassay (ELISA) and quantitative confirmatory analysis of free morphine concentrations in postmortem blood was performed by solid-phase extraction followed by gas chromatography/mass spectrometry (GC/MS) in the selected ion monitoring mode. While the practice of withdrawing life support from terminally ill patients, with the accompanying administration of narcotics/analgesics has been reported in the medical literature, it has not been adequately described in the forensic literature. The implications of this practice on the forensic toxicological interpretation of morphine findings are discussed. To our knowledge, this is the first report of postmortem morphine concentrations arising directly from administration in conjunction with withdrawal of care in pediatric patients. 相似文献
902.
A simulated clandestine shallow grave was created within a heterogeneous, made-ground, urban environment where a clothed, plastic resin, human skeleton, animal products, and physiological saline were placed in anatomically correct positions and re-covered to ground level. A series of repeat (time-lapse), near-surface geophysical surveys were undertaken: (1) prior to burial (to act as control), (2) 1 month, and (3) 3 months post-burial. A range of different geophysical techniques was employed including: bulk ground resistivity and conductivity, fluxgate gradiometry and high-frequency ground penetrating radar (GPR), soil magnetic susceptibility, electrical resistivity tomography (ERT), and self potential (SP). Bulk ground resistivity and SP proved optimal for initial grave location whilst ERT profiles and GPR horizontal "time-slices" showed the best spatial resolutions. Research suggests that in complex urban made-ground environments, initial resistivity surveys be collected before GPR and ERT follow-up surveys are collected over the identified geophysical anomalies. 相似文献
903.
904.
Linnet K Johansen SS Buchard A Munkholm J Morling N 《Forensic science international》2008,179(1):78-82
On the basis of simultaneously sampled postmortem blood specimens from the left and right femoral veins the pre-analytical variation of methadone measurements was evaluated and compared to the analytical variation. The material consisted of a series of 27 duplicate samples from routine autopsy cases comprising mainly drug addicts. A chiral LC-MS/MS method was used for measurement of the R- and S-enantiomers of methadone and its main metabolite 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium (EDDP). The analytical CV% was determined to be in the range 3-4% for methadone enantiomers and 4-6% for EDDP enantiomers. The total measurement uncertainty (CV(T)) was estimated from the pre-analytical variation (CV(PA)), analytical variation proper (CV(A)), and variation related to calibration (traceability) (CV(Cal)) according to the relationship CV(T) = [CV(2)(PA) + CV(2)(A) + CV(2)(cal)](0.5). Uncertainty related to calibration concerned a component related to the purity of drug reference compound and a contribution from the production of calibrator solutions (CV(Cal)<1%). Pre-analytical sampling variation was estimated from the duplicate measurements of blood samples after subtraction of the analytical component. The pre-analytical variation amounted to a CV% of 19-21% for R- and S-methadone and 30-38% for R- and S-EDDP, i.e. considerably larger than the other components. Due to the squared addition principle, the resulting total uncertainty (CV(T)) became largely identical to the CV(PA), i.e. 19-21% for R- and S-methadone and 31-38% for R- and S-EDDP enantiomers. Accordingly, CV(T) exceeded CV(A) by a factor 5 or more. Dominance of the pre-analytical component of variation may also be likely for other compounds measured in postmortem blood samples. Thus, the width of the 95%-uncertainty interval (+/-2CV(T)) for a postmortem measurement is largely determined by the pre-analytical component of variation. This should be kept in mind when judging on the uncertainty of postmortem measurement results. 相似文献
905.
The succession of insect communities on carrion varies at local and global spatial scales. As such, ecological succession data obtained from corpses at one geographic location cannot necessarily be applied to other locations. Our study describes this succession in the far southern part of China to provide such data for forensic cases in this region. A total of 18 pig carcasses were placed in the field in four seasons, and the timing of the following events were recorded: appearance of larvae, onset of larval wandering, when most larvae had wandered, onset of pupariation, when most larvae had pupariated, onset of eclosion and end of eclosion. Our results indicated that all of the evaluated events could be used as accurate indicators of postmortem interval (PMI). The carcasses decayed fairly quickly in spring, summer and autumn, taking 225+/-75 h, 183+/-44 h, and 247+/-70 h, respectively, to decay from the fresh stage to skeletonisation. In winter, carcasses needed longer (1180+/-291) to decay as much. Carcasses attracted 47 species of insect, with flies predominating. The larvae were mainly Chrysomya megacephala (Fabricius), Chrysomya rufifacies (Macquart) and Hydrotaea (Ophyra) spinigera (Stein). Most necrophagous insects were found all year around, and there were no marked differences in species among the four seasons, except that Dermestes maculatus (De Geer) was absent in winter. Blowflies produced only one generation on a carcass before it became skeletonised, which simplified the estimation of PMIs. 相似文献
906.
907.
A retrospective study was undertaken of all cases of death due to suicidal electrocution in Sydney, Australia between 1996 and 2005. A total of 25 cases were identified with 20 cases (80%) as a result of direct attachment to an electrical outlet and five cases (20%) as a result of immersion in a body of water with an electrical appliance. Twenty of the 25 individuals were men (mean age = 57 years, range 22-90) and five were women (mean age 67, range 53-88). At least 35% of decedents were either currently working or had worked as electricians. Electrical timers had been used in eight (32%) cases, the fuse blown in one case, but the remaining 16 (64%) bodies were "live" on arrival of witnesses or electricity personnel. This study demonstrates the phenomenon of electrical suicide as a regular occurrence in Sydney. We highlight the need for investigators and emergency workers to remain vigilant upon discovery of electrical suicides, due to the fact that most bodies remain electrically active after death. 相似文献
908.
Identification of colorants in pigmented pen inks by laser desorption mass spectrometry 总被引:1,自引:0,他引:1
Pigments are rapidly replacing dyes as colorants in pen and printer inks, due to their superior colors and stability. Unfortunately, tools commonly used in questioned document examination for analyzing pen inks, such as TLC, cannot be used for the analysis of insoluble pigments on paper. Laser desorption mass spectrometry is demonstrated here as a tool for analyzing pigment-based pen inks. A pulsed nitrogen laser can be focused onto a pen stroke from a pigmented ink pen on paper, and positive and negative ions representative of the pigment can be generated for subsequent mass spectrometric analysis. Targeted pens for this work were a set of Uni-ball 207 pigmented ink pens containing blue, light blue, orange, green, violet, red, pink, and black inks. Copper phthalocyanine was identified as the pigment used to make both blue inks. A mixture of halogenated copper phthalocyanines were identified in the green ink. Unexpectedly, the pink ink was found to contain a red pigment, Pigment Red 12, treated with a mixture of water-soluble dyes. Each sample yielded ions representative of the pigments present. 相似文献
909.
910.
In forensic anthropology, estimation of stature from feet dimensions plays a significant role in establishing personal identity. There is a scarcity of literature on the estimation of stature from foot length and foot breadth among various Indian populations, including the indigenous populations found in the northern part of the state of West Bengal, India. The Rajbanshis and the Meches are two such indigenous populations. The present study is an attempt to understand the relationship between stature and feet dimensions among Rajbanshi male and female individuals of North Bengal, India. Measurements of stature, foot length and foot breadth were recorded from 350 adult Rajbanshi and 100 adult Meche individuals (age range: 18-50 years) residing in different villages located in the Darjeeling District of West Bengal. The Technical Error of Measurements was within the accepted limits. The results of the present study indicate that female Rajbanshi individuals exhibit shorter stature and smaller feet than their male counterparts. Using ANOVA, it is determined that there was significant differences (p<0.05) in stature, foot length and foot breadth between sexes. Using paired t-test, it is further observed that bilateral variation was significant (p<0.05) within sexes with respect to foot length, but not with foot breadth (p>0.05). Stature, foot length and foot breadth are positively and significantly correlated with each other (p<0.01). The higher correlation coefficient between stature and foot length over that of stature and foot breadth points to the fact that foot length, rather than foot breadth, is more accurate in estimating stature. Sexual dimorphism is more pronounced than bilateral differences among Rajbanshi individuals. Using linear regression, it is observed that stature was strongly dependent on foot length and foot breadth. Foot breadth is strongly dependent on foot length. Prediction of stature is more accurate by using step-wise multiple regression. Age does not have a significant effect on stature estimation. The equations obtained for the Rajbanshis were fitted on the Meches to check whether the same equations could be utilized for both these indigenous communities. The equations obtained for another Indian population from the literature were also fitted and tested on the Rajbanshi. It may be concluded that the present study has provided equations to estimate stature from the feet dimensions among the Rajbanshis. It would be unwise to use the same equations for stature estimation for different Indian populations. 相似文献