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891.
892.
A 1H nuclear magnetic resonance (1H NMR) method for the determination of gamma-hydroxybutyric acid (GHB) and gamma-hydroxybutyrolactone (GBL) in human serum and urine using spiked samples has been developed. The method gives linear responses (correlation coefficients of 0.99 or greater) over the concentration range 0.01 mg/mL to 4.0 mg/mL in urine and 0.3 mg/mL to 2.0 mg/mL in serum. No sample pretreatment is required. Studies of the chemical interconversion of GBL and GHB showed hydrolysis of GBL to be rapid at pH 11.54, slower and less complete (30% hydrolysis) at pH 2.54 and slowest at pH 7.0, reaching 30% hydrolysis in about 40 days. No esterification of GHB was observed at any pH.  相似文献   
893.
A body was found behind a car with a noose tied around its neck, the other end of the rope tied to a tree. Apparently the man committed suicide by driving away with the noose tied around his neck and was dragged out of the car through the open hatchback. postmortem multislice-computed tomography (MSCT) and magnetic resonance imaging (MRI) indicated that the cause of death was cerebral hypoxia due to classic strangulation by hanging, and not due to a brainstem lesion because of a hang-man fracture as would be expected in such a dynamic situation. Furthermore, the MRI displayed intramuscular haemorrhage, bleeding into the clavicular insertions of the sternocleidomastoid muscles and subcutaneous neck tissue. We conclude that MSCT and MRI are useful instruments with an increased value compared with 2D radiographs to augment the external findings of bodies when an autopsy is refused. But further postmortem research and comparing validation is needed.  相似文献   
894.
Samples containing DNA from two or more individuals can be difficult to interpret. Even ascertaining the number of contributors can be challenging and associated uncertainties can have dramatic effects on the interpretation of testing results. Using an FBI genotypes dataset, containing complete genotype information from the 13 Combined DNA Index System (CODIS) loci for 959 individuals, all possible mixtures of three individuals were exhaustively and empirically computed. Allele sharing between pairs of individuals in the original dataset, a randomized dataset and datasets of generated cousins and siblings was evaluated as were the number of loci that were necessary to reliably deduce the number of contributors present in simulated mixtures of four or less contributors. The relatively small number of alleles detectable at most CODIS loci and the fact that some alleles are likely to be shared between individuals within a population can make the maximum number of different alleles observed at any tested loci an unreliable indicator of the maximum number of contributors to a mixed DNA sample. This analysis does not use other data available from the electropherograms (such as peak height or peak area) to estimate the number of contributors to each mixture. As a result, the study represents a worst case analysis of mixture characterization. Within this dataset, approximately 3% of three-person mixtures would be mischaracterized as two-person mixtures and more than 70% of four-person mixtures would be mischaracterized as two- or three-person mixtures using only the maximum number of alleles observed at any tested locus.  相似文献   
895.
A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested.  相似文献   
896.
Butane is inhaled in order to achieve a pleasurable state of intoxication. An overdose can lead to death. In two deaths from our own investigation material the circumstances were suspicious for the inhalation of liquid gas, and the presence of butane should be demonstrated in the respiratory gases. For detection, a method of ion trap gas chromatography/mass spectrometry (GC/MS) and tandem-mass spectrometry (GC/MS-MS) was developed, whereby the gas samples from the lung tissue were directly injected into the GC. The GC/MS tests revealed the presence of butane. Moreover, it was found that during the MS-MS tests reaction products appeared which had formed in the ion trap. Systematic investigations of these reaction products showed that these appeared regularly and could be used as additional backup for the proof of butane. Thus phenomena in the ion trap were used which would not have been expected to occur in normal mass spectrometry or tandem-MS and had not been described in the forensic literature so far. The detected amount of butane could be quantified by means of serial dilutions with nitrogen and room air. The described method shows that small molecules or gases can be demonstrated with the ion trap mass spectrometer.  相似文献   
897.
898.
This study reports on the reduction in violent offending in a population of serious and violent juvenile offenders following an intensive institutional treatment program. The treatment group (N=101) is compared to a similar group that was assessed but not treated (N=147). All youth were sent to the program from a juvenile corrections institution where they had received the customary rehabilitation services. The results show a significant reduction in the prevalence of recidivism in the treated group after controlling for time at risk in the community and other covariates. The effects of non-random group assignment were reduced by including a propensity score analysis procedure in the outcome analysis. Untreated comparison youth appeared to be about twice as likely to commit violent offenses as were treated youth (44% vs. 23%). Similarly, treated youth had significantly lower hazard ratios for recidivism in the in the community than the comparison youth, even after accounting for the effects of non-random group assignment.  相似文献   
899.
The present study tested the proposition that disengagement of moral self-sanctions enables prison personnel to carry out the death penalty. Three subgroups of personnel in penitentiaries located in three Southern states were assessed in terms of eight mechanisms of moral disengagement. The personnel included the execution teams that carry out the executions; the support teams that provide solace and emotional support to the families of the victims and the condemned inmate; and prison guards who have no involvement in the execution process. The executioners exhibited the highest level of moral, social, and economic justifications, disavowal of personal responsibility, and dehumanization. The support teams that provide the more humane services disavowed moral disengagement, as did the noninvolved guards but to a lesser degree than the support teams.  相似文献   
900.
Korea recently introduced three major health care reforms: in financing (1999), pharmaceuticals (2000), and provider payment (2001). In these three reforms, new government policies merged more than 350 health insurance societies into a single payer, separated drug prescribing by physicians from dispensing by pharmacists, and attempted to introduce a new prospective payment system. This essay compares the three reforms in Korea and draws important lessons about the country's changing process and politics of health care policy. The change of government, the president's keen interest in health policy, and democratization in the public policy process toward a more pluralist context opened a policy window for reform. Civic groups played an active role in the policy process by shaping the proposals for reform-a major change from the previous policy process that was dominated by government bureaucrats. The three reforms also showed important differences in the role of interest groups. Strong support by the rural population and labor unions contributed to the financing reform. In the pharmaceutical reform, which was a big threat to physician income, the president and civic groups succeeded in quickly setting the reform agenda; the medical profession was unable to block the adoption of the reform but their strikes influenced the content of the reform during implementation. Physician strikes also helped block the implementation of the payment reform. Future reform efforts in Korea will need to consider the political management of vested interest groups and the design of strategies for both scope and sequencing of policy reforms.  相似文献   
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