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991.
Forensic arthropod succession patterns are known to vary between regions. However, the northern habitats of the globe have been largely left unstudied. Three pig carcasses were studied outdoors in Whitehorse, Yukon Territory. Adult and immature insects were collected for identification and comparison. The dominant Diptera and Coleoptera species at all carcasses were Protophormia terraneovae (R‐D) (Fam: Calliphoridae) and Thanatophilus lapponicus (Herbst) (Fam: Silphidae), respectively. Rate of decomposition, patterns of Diptera and Coleoptera succession, and species dominance were shown to differ from previous studies in temperate regions, particularly as P. terraenovae showed complete dominance among blowfly species. Rate of decomposition through the first four stages was generally slow, and the last stage of decomposition was not observed at any carcass due to time constraints. It is concluded that biogeoclimatic range has a significant effect on insect presence and rate of decomposition, making it an important factor to consider when calculating a postmortem interval.  相似文献   
992.
The use of narrow‐banded visible light sources in improving the visibility of injuries has been hardly investigated, and studies examining the extent of this improvement are lacking. In this study, narrow‐banded beams of light within the visible light spectrum were used to explore their ability in improving the visibility of external injuries. The beams of light were induced by four crime‐lites® providing narrow‐banded beams of light between 400 and 550 nm. The visibility of the injuries was assessed through specific long‐pass filters supplied with the set of crime‐lites®. Forty‐three percent of the examined injuries improved in visibility by using the narrow‐banded visible light. In addition, injuries were visualized that were not visible or just barely visible to the naked eye. The improvements in visibility were particularly marked with the use of crime‐lites® “violet” and “blue” covering the spectrum between 400–430 and 430–470 nm. The simple noninvasive method showed a great potential contribution in injury examination.  相似文献   
993.
Locating exactly where trace explosive residue samples should be sought during sample collection at bomb scenes is not specified in the published literature or guidelines; in this area, it is generally acknowledged that forensic practices are based on tradition rather than evidence. This study investigated patterns in the spatial distribution of postblast 1,3,5‐trinitro‐1,3,5‐triazocyclohexane residue from a series of unconfined detonations, over a range of sampling sites, and at two different detonation heights. The amount of residue recovered from the sites decreased as a function of distance from the center of the explosion. [Correction added after online publication 27 December 2012: In the preceding sentence, “increased” was corrected to “decreased” to agree with the conclusion of the article.] As the height of the detonations increased, more residues were found from all sampling sites. The findings of this empirical study have a number of important practical implications including determining where residue samples are best sought at crime scenes.  相似文献   
994.
The authors report an unusual case of suicide of an anesthesiologist, in which the suicide manner and means depend upon the victim's occupation. This is the first case report published in Italy of a death involving propofol and other drugs. The anesthesiologist was found dead with an empty drip still inserted in the hand and another one near his body. Forensic and toxicological findings suggested that the cause of death was a respiratory depression due to a self‐administration of a rapidly infused lethal drug mixture. Analytical drug quantification was performed by gas chromatography‐mass spectrometry. Blood analysis revealed: zolpidem (0.86 μg/mL), propofol (0.30 μg/mL), midazolam (0.08 μg/mL), thiopental (0.03 μg/mL), and amitriptyline (0.07 μg/mL). Adipose tissue and hair analysis suggested a previous and repeated use of these drugs verifying the fact that in Italy recreational abuse of anesthetic and sedative agents in health care practitioners is becoming an increasing problem.  相似文献   
995.
The foot measurements are important in forensic field as they can be used as body height predictors for an individual. The morphology of human feet shows the variations and therefore the aim of this study was to find the relation between stature and foot measurements and to generate population‐specific equations. We measured the stature and bilateral foot measurements of 71 volunteers ranging in age between 18 and 27 years using standard measurements technique. The results revealed nonsignificant bilateral differences in all sex groups (< 0.05). Sex differences were found to be significant in all foot measurements (< 0.001). The highest significant and positive correlation coefficients with stature were observed for foot length in males (r = 0.759), in females (r = 0.722), and in the sex‐mixed group (r = 0.865). According to the nonsignificant sex effects on the relation between stature and foot dimensions, the regression equations were computed only for the pooled mixed‐sex group. Our study provides equations that can help to estimate stature from foot measurements among Slovaks.  相似文献   
996.
Fibers are a commonly encountered evidence type and fiber comparisons are routinely conducted. When the characteristics of questioned and known fibers correspond, the probative value is limited because the characteristics compared are determined by their manufacture. It would be valuable to test the hypothesis that questioned fibers originated from a specific carpet. One means of testing this is to analyze fine particles on the fibers. A procedure was developed for removing adhering particles from fibers and preparing them for scanning electron microscopy/ energy dispersive X‐ray spectrometry (SEM/EDS) analysis. The efficacy of several fluids (acetone, ethanol, hexanes, aqueous ethanol, aqueous sodium hexametaphosphate) and agitation methods (sonication and vortexing) for removing particles from fibers was evaluated. The most effective method evaluated was sonication in ethanol for 10 min. The recovered particles were filtered onto a polycarbonate filter and analyzed by automated SEM/EDS analysis to generate data on the particle assemblage. This method makes possible future research to test the within‐item and between‐item variability of particle assemblages on fibers.  相似文献   
997.
Comparative analyses of 50 single‐layer white architectural paints were conducted to determine the discrimination power using standard techniques and to provide a basis for assessing significance when paints with limited features are not discriminated. Utilizing Fourier transform infrared spectroscopy (FTIR), 68 undifferentiated pairs resulted, yielding a discrimination of 94.45%. Adding stereomicroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and backscatter electron (BSE) imaging, and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS), the overall discrimination was 99.35%. The study included blind verification replicates, which resulted in the only pairs without indications of physical or chemical differences. The remaining groups of undifferentiated samples contained subtle differences by at least one technique, but were considered undifferentiated for the discrimination power evaluations. This study demonstrates a high degree of discrimination of single‐layer white architectural paints using methods of analysis often encountered in forensic science laboratories.  相似文献   
998.
Much contemporary debate in forensic science concerns validity and admissibility of scientific evidence in court. In this paper, three current approaches to facial identification—image superimposition, photogrammetry, and morphological analysis—are considered with regard to criteria for scientific evidence in the United States, and England, and Wales. The aim of the paper is to assess the extent to which facial image comparison meets criteria of admissibility in these jurisdictions. The method used is a comparative evaluation of the methods of facial image comparison and their underlying premises against the range of admissibility criteria reported in court rulings and relevant judicial and scientific inquiries in the United States and the United Kingdom. While the techniques of facial image comparison are generally accepted within their practitioner communities, they are not tested, and their error rates are unknown. On that basis, the methods of facial image comparison would appear not to meet the anticipated standards. They are, nevertheless, admitted in court in the United States, and England, and Wales. This paper concludes that further research in science and law will be necessary to more definitively establish admissibility of facial image comparison evidence, as it will for other nascent and novel methods that are potentially influential in court proceedings.  相似文献   
999.
Simple, reliable, sensitive, and accurate spectrofluorimetric and spectrophotometric methods were proposed for the determination of two selected analgesic drugs, namely tramadol and morphine, in pharmaceuticals and biological fluids. The proposed methods were based on the oxidation of the studied drugs by Cerium (Ce)IV in an acidic medium. The spectrofluorimetric method is based on measuring the relative fluorescence intensity of Ce(III) arising from Ce(IV) at 350 nm with an excitation wavelength at 250 nm. The spectrophotometric method involves on addition of a known excess of Ce(IV) to the studied drugs in an acid medium, followed by the determination of residual Ce(IV) by reacting with a fixed amount of methyl orange and measuring the absorbance at 510 nm. Different variables affecting the reaction conditions, such as the concentrations of Ce(IV), type and concentration of the acid medium, reaction time, temperature, and the diluting solvents, were carefully studied and optimized.  相似文献   
1000.
The palatine rugae possess unique characteristics that could be used when it is difficult to identify a dead person according to fingerprints or dental records. They are permanent and unique to each person. The rugae are surrounded by cheeks, lips, tongue, and buccal pad of fat; hence, they remain protected in trauma, incineration, or mass disasters. Their pattern of orientation is formed by the 12th to 14th week of gestation and remains stable throughout life. In this study, dental casts of 120 patients were analyzed for individual rugae characteristics and strength and subsequent individual codes were given. No two individuals were having exactly matching rugae codes. Dimensions of rugae pattern, incisive papilla, and midpalatal raphe were also noted. Rugae were reevaluated after one year to check its stability, which showed no significant difference. The coding system followed can be adopted as a good and simple technique to achieve electronic transfer of the records of the palatal rugae.  相似文献   
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