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981.
In forensic image processing, it is often important to be able to separate a feature from an interfering background or foreground, or to demonstrate colors within an image to be different from each other. In this study, a color deconvolution algorithm that could accomplish this task is described, and it is applied to color separation problems in document and fingerprint examination. Subtle color differences (sometimes invisible to the naked eye) are found to be sufficient, which is demonstrated successfully for several cases where color differences were shown to exist, or where colors were removed from the foreground or background. The software is available for free in the form of an Adobe Photoshop-compatible plug-in.  相似文献   
982.
The average exclusion probability is a measure of efficiency in paternity testing; it refers to the a priori ability of a battery of tests to detect paternity inconsistencies. This parameter measures the capacity of the system to detect a false accusation of paternity. Traditionally, this average exclusion probability has been estimated as the probability of excluding a man who is not the father by an inconsistency in at least one of the studied loci. We suggest that this criterion should be corrected, as currently the presumed father is excluded when at least three genetic inconsistencies are found with the child being tested, not just one. This change of criterion has occurred because of the use of microsatellite loci, whose mutation rates are much greater than those of the coding genes used previously in paternity studies. We propose the use of the average probability of exclusion for at least three loci (not only one), as an honest measure of the combined probability of exclusion of several loci, and we propose an algebraic expression to calculate it.  相似文献   
983.
We present three cases of fatal dog maulings of infants placed in mobile infant swings, a phenomenon not previously described in the literature. In each case, the victim was left in a mobile swing, unsupervised by an adult, and the attacking dog was a family pet. Case 1 involved an 18-day-old male infant attacked by a pit bull; Case 2 involved a 3-month-old male infant attacked by a Chow Chow and/or a Dachshund, and Case 3 involved an 18-day-old female infant attacked by a Labrador-pit bull mix. These cases not only underscore the importance of not leaving young children unattended in the presence of pet dogs, but also raise the possibility that mobile swings may trigger a predatory response in dogs and thus may represent an additional risk factor for dog attack.  相似文献   
984.
The first case of application of forensic entomology in the Brazilian Amazonia is described. The corpses of 26 men were found in the rainforest in Rondonia State, Brazil. Fly larvae collected on the bodies during autopsy were identified as Paralucilia fulvinota (Diptera, Calliphoridae). No data or specimens were collected at the crime scene. At the laboratory, the larvae developed into pupae in 58 h and into adults in 110.5 h. The total development time for P. fulvinota was measured in field experiments inside the forest. The age of the larvae when collected from the bodies was estimated as the difference between the time required for them to become adults and the total development time for this species. The estimated age of the maggots and the minimum postmortem interval was 5.7 days.  相似文献   
985.
Reproductive genetic technologies are becoming more controversial as they become more ubiquitous. The opponents of these technologies are largely religious groups, a fact that leads to the question of why religious groups would be more opposed to these technologies than others. Since all of these technologies are justified by their ability to relieve suffering of some kind, it is hypothesized that the actively religious have a notion of suffering different from that of advocates for these technologies, and this different notion of suffering leads to opposition to the technologies. In this article I report on a qualitative interview study of the religiously active in the United States. I find that the religiously active do have views of suffering that are distinct from the medical consensus, and these views are related to people's conclusions about the advisability of reproductive genetic technologies.  相似文献   
986.
Historically, fatal injury monitoring and surveillance have relied on mortality data derived from death certificates (DC). However, problems associated with utilizing DC have been well documented. Recently, access to and utilization of hospital discharge data (HDD) have offered a new and important secondary source of data regarding in-hospital deaths. However, studies have shown that discrepancies between the HDD and the corresponding DC often exist. This discrepancy was especially evident when comparing HDD to the vital statistics data (VSD) for deaths by falls among those aged 65 and over in 19 states.This was a retrospective forensic review of elderly (age 65 and over) fall-associated fatalities (E880-E888) identified from HDD and VSD in Allegheny County, Pennsylvania, between 1997 and 1998. Seventy-seven cases were identified, with the original manner of death listed as natural (34), suicide (1), and accidental (42) on the DC. Following a forensic review of the cases, the manner of the death on the DC should have been changed from natural to accidental in 28% (n = 12) of the cases, representing an undercount in the VSD. Undercounts were due to a failure of clinicians to account for the significance of a fall event that contributed to subsequent pathology and death. In addition, in that 22% (n = 17) of the HDD fall-associated deaths, the fall did not contribute directly or sequentially to the underlying cause of death, thereby representing an overcount in the HDD.Based on these findings we recommend (1) elderly fall surveillance systems should only count HDD E-coded falls that demonstrate a serious traumatic injury which directly or subsequently results in death, (2) all in-hospital fall-associated deaths should be reported to and reviewed by coroner/Medical Examiner offices for determination of the cause and manner of death, and (3) physicians should be better educated in properly completing death certificates.  相似文献   
987.
In the period 1995-1999 there were 388 car exhaust-gas suicides in Denmark. Of these 343 (88.4%) were men and 45 (11.6%) were women, the average age being 47 years. The car exhaust-gas suicides made up 9.3% of all suicides in Denmark in the period. The corresponding rate was 11.7% for men and 3.7% for women. In rural areas a larger part of all suicides were committed with car exhaust-gas compared to the more densely populated areas. Mental disease was diagnosed in 124 (32.0%) cases. A suicide note was found in 165 (42.5%) cases. A hose was fitted to the exhaust pipe in 334 (86.1%) cases. Of these the 234 (60.3%) occurred outside, typically in a forest area, while 76 (19.6%) occurred in a closed garage. All the 54 (13.9%) cases with no hose fitted to the exhaust pipe occurred in a garage. Seven (1.8%) victims were found in a burning or burnt-out car, where the following investigation revealed that it was actually a car exhaust-gas suicide. Carboxyhemoglobin was measured in 26 (6.7%) victims. In two of these victims no carboxyhemoglobin was found, as they had survived for some time after the poisoning. The average saturation of the remaining victims was 67%, the lowest saturation being 20% and the highest being 84%. In the period 1969-1987 the number of car exhaust-gas suicides in Denmark increased from 50 to approximately 190 per year and the rate of car exhaust-gas suicides compared to all suicides increased from approximately 5% to approximately 13%. In 1987-1999 these figures decreased from approximately 190 to 63 per year and from 13% to approximately 8%. During these 30 years the number of passenger cars in Denmark doubled, which explains the increase in car exhaust-gas suicides during 1969-1987. A possible explanation for the decrease in 1987-1999 is the introduction of the catalytic converter, which was made mandatory in 1990. We anticipate that car exhaust-gas suicides will continue to decrease in numbers, as more cars are equipped with catalytic converters.  相似文献   
988.
Spinal epidural haematomas (sEDH) can be regarded as rare events, in principle a spontaneous and a traumatic aetiology can be distinguished. Spontaneous spinal epidural haematomas can arise, e.g. from vascular malformations, coagulopathies, etc. On the other hand, traumatic sEDH are related to, e.g. spinal trauma or intraoperative vascular injuries. With regard to clinical significance, spinal epidural haematomas accompanied by transient mild neurological symptoms up to lethal outcomes have been observed. We report on a 53-year-old male alcoholic who was found in the kitchen of his asylum in a grotesquely fixed body position, with his head and cervical spine in a maximum anteflected position. A general practitioner had ruled for a non-natural manner of death due to "broken neck" and alcohol intoxication, therefore, the prosecution authorities called for a medicolegal autopsy. At autopsy, paravertebral soft tissue haemorrhage in between the shoulder blades was disclosed. Furthermore, a spinal epidural haematoma, extending from the foramen magnum down to the middle portion of the thoracic spine was found. No fractures of vertebrae nor lesions of spine ligaments or bleedings of intervertebral discs were found. Blood alcohol concentration was determined 1.92 g/l and urine alcohol concentration was 1.76 g/l. Further morphological findings were cerebral oedema and cardiac hypertrophy; the urinary bladder was found filled to bursting. Neuropathological investigations confirmed the presence of the spinal epidural haematoma and assigned lethal significance to this finding. There were no histological signs of axonal injury. Reconstruction revealed that when sitting on a chair in a drunk condition, the individual's upper part of the body had fallen backwards in the corner and subsequently got stuck with maximum anteflection of the head and cervical spine, causing rupture of vessels and spinal epidural haematoma. Acute respiratory failure caused by impairment of the phrenic nerve following spinal epidural haematoma with potential synergism of alcohol intoxication was ascertained as the cause of death.  相似文献   
989.
In forensics and archaeology, it is important to distinguish human from animal remains and to identify animal species from fragmentary bones and bloodstains. We report blind tests in which a protein radioimmunoassay (pRIA) was used to identify the species of six bone fragments lacking morphological specificity and 43 bloodstained lithic tools, knapped experimentally and soaked in blood of known animal and human origin. The submitters of the bone fragments and the bloodstained tools each listed a number of possible species, from which the testers selected the best match with the pRIA results. All six bone fragments were correctly identified: three humans, a deer, a dog, and a cow. Forty-three tools were stained with blood from a wide variety of species including ungulates, carnivores, a fish, and a bird. On 40 of these 43, at least one species (or blood-free control) was identified correctly. Some of the tools were stained with blood of two different species. A mixture of sheep and musk ox blood was correctly identified; in several other mixtures, only a single species was detected. Two tools with human blood and one with human sweat were correctly reported as human. There was a single false positive (one of three controls reported as weakly bovine) and no false negatives. We conclude that the pRIA technique shows a high degree of accuracy in discriminating human from animal bone fragments and bloodstains and in identifying animal species.  相似文献   
990.
A collaborative study was conducted in France in order to determine the prevalence of cannabinoids, opiates, cocaine metabolites and amphetamines in blood samples from drivers killed in road accidents in 2003 and 2004 and to compare these values with those of a previous study performed during the period 2000-2001 involving 900 drivers. Blood samples were provided from 2003 under 30-year-old drivers, killed in a traffic accident. Drugs of abuse were determined by gas chromatography-mass spectrometry using the same analytical procedures in all the 12 laboratories. The most frequently observed compounds were by far cannabinoids, that tested positive in 39.6% of the total number of samples. Delta9 tetrahydrocannabinol (THC), the most active of the principle constituents in marijuana (cannabis sativa), was detected in the blood of 28.9% drivers and was the single drug of abuse in 80.2% of the positive cases. It was associated with amphetamines in 7.4% and with opiates and cocaine in 1.9 and 4.8%, respectively. Amphetamines were present in 3.1% of the total number of samples, cocaine metabolites in 3.0% and opiates in 3.5%. When comparing these results with those of a previous study performed 3 years before, a significant increase is observed for THC (28.9% versus 16.9%), cocaine metabolites (3.0% versus 0.2%) and amphetamines (3.1% versus 1.4%). This study demonstrates the critical necessity of implementing in France as soon as possible systematical roadside testing for drugs of abuse.  相似文献   
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