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971.
The act of leaving a victim's body in an unusual position is a conscious criminal action by an offender to thwart an investigation, shock the finder and investigators of the crime scene, or give perverted pleasure to the killer. The unusual position concepts of posing and staging a murder victim have been documented thoroughly and have been accepted by the courts as a definable phenomenon. One staging case and one posing case are outlined and reveal characteristics of those homicides. From the Washington State Attorney General's Homicide Investigation and Tracking System's database on murder covering the years 1981-2000 (a total of 5,224 cases), the relative frequency of unusual body dispositions is revealed as a very rare occurrence. Only 1.3% of victims are left in an unusual position, with 0.3% being posed and 0.1% being staged. The characteristics of these types of murders also set them apart: compared to all other murders, in staged murders the victims and killers are, on average, older. All victims and offenders in the staged murders are white, with victims being disproportionately white in murders with any kind of unusual body disposition. Likewise, females stand out as victims when the body is posed, staged, or left in other unusual positions. Whereas posed bodies are more likely to include sexual assault, often in serial murders, there is no evidence of either in the staged cases. Lastly, when a body is left in an unusual position, binding is more likely, as well as the use of more "hands on" means of killing the victim, such as stabbing or cutting weapons, bludgeons, ligatures, or hands and feet.  相似文献   
972.
The utility of pulmonary interstitial emphysema (PIE) in live birth determination is not well established. Because the distinction between live birth and stillbirth may be important in criminal proceedings, we undertook this study to investigate the relationship between the histologic finding of PIE and live birth. Sixty-six cases of infant death were retrieved and compared with 21 stillborn infants. Histologic sections of the lungs were characterized as "florid PIE," "equivocal PIE," or "absent PIE." Sixteen cases of florid PIE were identified, all in live born infants. Forty-seven cases of equivocal PIE were found in 36 live born and 11 stillborn infants. In 24 cases (14 live born infants and 10 stillborns), no PIE was identified. We examined the relationship between florid PIE in infants with sudden infant death syndrome (SIDS) or "sudden unexpected death in infancy, manner undetermined" (SUDI), and also its relationship to other variables. No association was found. The presence of equivocal PIE may be an artifact of tissue processing. Florid PIE is found only in live born infants. No correlation between the presence of florid PIE and cause of death could be determined.  相似文献   
973.
A controlled laboratory experiment is described, in principle and practice, which can be used for the of determination the rate of tissue decomposition in soil. By way of example, an experiment was conducted to determine the effect of temperature (12 degrees, 22 degrees C) on the aerobic decomposition of skeletal muscle tissue (Organic Texel x Suffolk lamb (Ovis aries)) in a sandy loam soil. Measurements of decomposition processes included muscle tissue mass loss, microbial CO2 respiration, and muscle tissue carbon (C) and nitrogen (N). Muscle tissue mass loss at 22 degrees C always was greater than at 12 degrees C (p < 0.001). Microbial respiration was greater in samples incubated at 22 degrees C for the initial 21 days of burial (p < 0.01). All buried muscle tissue samples demonstrated changes in C and N content at the end of the experiment. A significant correlation (p < 0.001) was demonstrated between the loss of muscle tissue-derived C (Ct) and microbially-respired C (Cm) demonstrating CO2 respiration may be used to predict mass loss and hence biodegradation. In this experiment Q10 (12 degrees C-22 degrees C) = 2.0. This method is recommended as a useful tool in determing the effect of environmental variables on the rate of decomposition of various tissues and associated materials.  相似文献   
974.
A simple method for analyzing nitrite in urine has been developed to confirm and quantify the amount of nitrite in potentially adulterated urine samples. The method involved separation of nitrite by capillary electrophoresis and direct UV detection at 214 nm. Separation was performed using a bare fused silica capillary and a 25 mM phosphate run buffer at a pH of 7.5. Sample preparation consisted of diluting the urine samples 1:20 with run buffer and internal standard, and centrifuging for 5 min at 2500 rpm. The sample was hydrodynamically injected, then separated using -25 kV with the column maintained at 35 degrees C. The method had upper and lower limits of linearity of 1500 and 80 microg/mL nitrite, respectively, and a limit of detection of 20 microg/mL. The method was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) protocol (Document EP10-A2), and validated using controls, standards, and authentic urine samples. Ten anions, ClO-, CrO4(-2), NO3-, HCO3-, I-, CH3COO-, F-, SO4-, S2O8(-2), and Cl-, were tested for potential interference with the assay. Interferences with quantitation were noted for only CrO4(-2) and S2O8(-2). High concentrations of Cl- interfered with the chromatography. The method had acceptable accuracy, precision, and specificity.  相似文献   
975.
This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.  相似文献   
976.
Suppression of environmental science   总被引:1,自引:0,他引:1  
  相似文献   
977.
Weight force during prone restraint and respiratory function   总被引:1,自引:0,他引:1  
Prone maximal restraint position (PMRP, also known as hogtie or hobble) is often used by law enforcement and prehospital personnel on violent combative individuals in the field setting. Weight force is often applied to the restrained individual's back and torso during the restraint process. We sought to determine the effect of 25 and 50 lbs weight force on respiratory function in human subject volunteers placed in the PMRP. We performed a randomized, cross-over, controlled trial on 10 subjects placed in 4 positions for 5 minutes each: sitting, PRMP, PRMP with 25 lbs weight force (PMRP+25), and PRMP with 50 lbs weight force placed on the back (PMRP+50). We measure pulse oximetry, end-tidal CO2 levels, and forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). FVC and FEV1 were significantly lower in all restraint positions compared with sitting but not significantly different between restraint positions with and without weight force. Moreover, mean oxygen saturation levels were above 95% and mean end-tidal CO2 levels were below 45 mm Hg for all positions. We conclude that PMRP with and without 25 and 50 lbs of weight force resulted in a restrictive pulmonary function pattern but no evidence of hypoxia or hypoventilation.  相似文献   
978.
979.
The neurologic manifestations of thallium poisoning include a severely painful ascending peripheral neuropathy, autonomic dysfunction, cranial nerve abnormalities, and a toxic encephalopathy. Although thallium has a short half-life, these neurologic manifestations commonly progress, even as the blood concentration of thallium decreases. This suggests either that thallium persists in neuronal tissues or that it initiates an injury cascade that takes time to fully manifest. As the latter mechanism is consistent with many toxin exposures, the concept of a central nervous system reservoir for thallium is often discounted. A recent case provided a unique opportunity to evaluate this possibility. A 48-year-old man was acutely and chronically thallium poisoned by his common-law wife. During his initial exposures, only gastrointestinal symptoms manifested. Following an acute ingestion, hospitalization was required. Over 3 days, his symptoms rapidly progressed from a severely painful neuropathy to slurred speech, ptosis, confusion, coma, respiratory insufficiency, and death. Because of considerations of alternative diagnoses, 2 lumbar punctures were performed, one on admission and another on the day of his death. Serum thallium concentrations obtained from stored blood samples were paired with spinal fluid concentrations from the same days. On day 1, serum and spinal fluid concentrations were 8700 mu/L and 1200 mu/L, respectively. On day 3, although the serum concentration had fallen to 7200 mu/L, the spinal fluid concentration had increased to 2100 mu/L. This case provides evidence to support the hypothesis that thallium distributes into the central nervous system more slowly than the blood compartment, and this may in part account for the progression of neurologic findings in the setting of decreasing serum concentrations.  相似文献   
980.
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