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211.
Doble P Sandercock M Du Pasquier E Petocz P Roux C Dawson M 《Forensic science international》2003,132(1):26-39
Detection and correct classification of gasoline is important for both arson and fuel spill investigation. Principal component analysis (PCA) was used to classify premium and regular gasolines from gas chromatography-mass spectrometry (GC-MS) spectral data obtained from gasoline sold in Canada over one calendar year. Depending upon the dataset used for training and tests, around 80-93% of the samples were correctly classified as either premium or regular gasoline using the Mahalanobis distances calculated from the principal components scores. Only 48-62% of the samples were correctly classified when the premium and regular gasoline samples were divided further into their winter/summer sub-groups. Artificial neural networks (ANNs) were trained to recognise premium and regular gasolines from the same GC-MS data. The best-performing ANN correctly identified all samples as either a premium or regular grade. Approximately 97% of the premium and regular samples were correctly classified according to their winter or summer sub-group. 相似文献
212.
Schmidt P Schmolke C Musshoff F Menzen M Prohaska C Madea B 《Forensic science international》2003,133(3):204-211
In animal experiments and in cell culture, chronic morphine treatment has been followed by "up-regulation" as well as "down-regulation" of the mu-opioid receptor (OR) number. The present postmortem morphometric study of morphine-related fatalities of drug-addicts (n=13, 20-35 years old, with blood unconjugated morphine levels from 27.1 ng/ml to 458 ng/ml, m.v. 198.5 ng/ml) versus a non-addicted control group (n=13, 10-44 years old) was intended to examine, whether chronic opiate exposure affects the numerical density of mu-OR expressing neurons in the human neocortex (areas 11, 24 and 25 according to Brodmann). For the immunohistochemical procedure, vibratome sections (100 microm) were incubated with a monoclonal antibody against the mu-OR, diluted 1:100, and immunolabelled sites were visualized using an immunoperoxidase protocol. The numerical densities of OR immunoreactive neuronal profiles and Nissl-stained central profiles were assessed morphometrically (camera lucida-drawings). In both groups, the anti-mu-OR-immunoreactivity was mainly localized in pyramidal neurons of layers (L) II/III and V and in multiform neurons of L VI. In the areas 24 and 25, the density of the immunoreactive neuronal profiles did not display a significant difference between the two examined groups. In the area 11, however, the number of immunolabelled neuronal profiles amounted to 2777+/-206 mm(3) in the drug-related fatalities and to 2320+/-124 mm(3) in the control group and thus was significantly increased. 相似文献
213.
195 cases of homicide, grouped according to juridical assessment, were retrospectively analysed with regard to individual characteristics of perpetrators and victims, circumstances, and mode of commitment. The involvement of underage victims and perpetrators as well as differences between the urban and rural areas studied were taken into special consideration. To summarise, the majority of the offences studied was carried out by a male perpetrator with a mean age of 35 years driven by personal motives or greed in his immediate vicinity and affected family members or close acquaintances. The fatal injuries were mainly attributable to sharp or blunt force. With regard to killings of children, a higher prevalence of female victims and male assailants, emotional motives and an even higher importance of the social vicinity were found. Particularly in victims younger 12 years of age, manual modes of commitment without application of any tools were predominantly encountered. The comparison of urban and rural areas revealed a higher homicide rate in municipal areas especially of offences with a loose relationship between victims and assailants (greed, sexual assault). In contrast, rural areas exhibited higher rates of bodily harm with fatal consequences as well as offences by highly intoxicated assailants. 相似文献
214.
A method was developed to screen for pepper spray residue using instruments and methods other than those techniques commonly employed to analyze chemical residue (i.e.. gas chromatography mass spectrometry-GCMS or liquid chromatography mass spectrometry-LCMS). The method employed gas chromatography (GC), thin layer chromatography (TLC), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to screen for dried pepper spray stains. Pepper sprays from nine different manufacturers were investigated. Capsaicin and dihydrocapsaicin were identified and unique IR reflectance spectra are presented. An additional five compounds were presumptively found. Results showed that a particular stain could be characterized as a pepper-based stain. 相似文献
215.
Virtopsy-postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in a fatal scuba diving incident 总被引:7,自引:0,他引:7
Plattner T Thali MJ Yen K Sonnenschein M Stoupis C Vock P Zwygart-Brügger K Kilchör T Dirnhofer R 《Journal of forensic sciences》2003,48(6):1347-1355
The body of a 44-year-old scuba diver was examined using postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), and findings were verified by subsequent autopsy. The goal was to find out whether the important pathomorphological findings for the reconstruction of events and the identification of cause and manner of death could be identified using modem digital cross-sectioning techniques. The findings of a massive vital decompression with pulmonary barotrauma and lethal gas embolism were identified in the radiological images. MSCT and MRI were superior to autopsy in the demonstration of the extent and distribution of gas accumulation in intraparenchymal blood vessels of internal organs as well as in areas of the body inaccessible by standard autopsy. 相似文献
216.
The presence of cocaine in illicit drug samples is still being determined in some laboratories using spot tests and microcrystal tests. Seventeen chemical species were tested using three different spot tests (Wagner, Marquis, and cobalt thiocyanate followed by stannous chloride reactions) and two microcrystal tests (gold chloride and platinic chloride) to determine whether the results could be differentiated from the results of these tests on cocaine. The data obtained indicated that nine of the 17 compounds gave results similar to those from cocaine using the three spot tests, but that the results from microcrystal testing allowed for differentiation of all nine compounds from cocaine. 相似文献
217.
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219.
The Principle of Full Compensation in Tort Law 总被引:2,自引:2,他引:0
According to the principle of full compensation, tort law seeks to put the victim in the position he was in before the tort. This position is generally considered to be the situation where the victim does not suffer any harm at all. We consider an alternative interpretation. If an injurer takes due care, the victim is faced with expected harm. This can be considered the victim's expected harm in the situation he was in before the tort. Thus conceived full compensation requires a negligent injurer to pay damages which bring the (potential) victim ex ante in the same position as the victim was in the case where the (potential) injurer takes due care. We investigate the consequences of this restated negligence rule. For due care levels larger than efficient care, the standard negligent rule may lead to excessive care, whereas the restated negligent rule always leads to efficient care. Furthermore, the activity level under the restated negligent rule is greater than the activity level under the standard negligent rule, which itself is greater than the efficient activity level. Social welfare under the restated negligence rule can either be higher or lower than social welfare under the standard negligence rule. 相似文献
220.
Garnishment of wage as a way for creditors to enforce payment by unwilling or insolvent debtors, while very common in Germany and Switzerland, is not very successful. Based on a dynamic model of debtor behaviour, this paper explores two alternatives of reform. One is to reduce the rate of garnishment, which at present amounts to 100 percent of the wage income exceeding a defined subsistence level, thus probably destroying incentives to work. According to model simulations, reducing the rate of garnishment is likely to result in an increase of labour supply but a decrease of garnishment revenue per period. Second, the introduction of a debt release as it exists in the United States would have an ambiguous effect on labour supply. While providing debtors with a fresh start, it would result a partial loss for creditors. A Pareto improvement thus does not seem to be possible. When taxpayers as an involved third party are taken into account, however, a potential Pareto improvement appears attainable through debt release. 相似文献