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91.
Four reality monitoring variables were used to discriminate suspect from foil identifications in 183 actual criminal cases. Four hundred sixty-one identification attempts based on five and six-person lineups were analyzed. These identification attempts resulted in 238 suspect identifications and 68 foil identifications. Confidence, automatic processing, eliminative processing and feature use comprised the set of reality monitoring variables. Thirty-five verbal confidence phrases taken from police reports were assigned numerical values on a 10-point confidence scale. Automatic processing identifications were those that occurred “immediately” or “without hesitation.” Eliminative processing identifications occurred when witnesses compared or eliminated persons in the lineups. Confidence, automatic processing and eliminative processing were significant predictors, but feature use was not. Confidence was the most effective discriminator. In cases that involved substantial evidence extrinsic to the identification 43% of the suspect identifications were made with high confidence, whereas only 10% of the foil identifications were made with high confidence. The results of a laboratory study using the same predictors generally paralleled the archival results. Forensic implications are discussed.  相似文献   
92.
The solution parameters associated with gradient elution reversed phase high-performance liquid chromatography (HPLC) were characterized by evaluating the electrospray ionization mass spectrometry (ESIMS) response of selected smokeless powder additives. Using direct liquid infusion, the positive ion ESIMS responses were determined for three general classes of powder constituents: dialkylphthalate acid esters, N,N'-dialkyl-N,N'-diphenyl urea based stabilizers and nitroso-, nitro-, and dinitro- derivatives of diphenylamine. The relative ESIMS intensities of the powder components were investigated as a function of three solution parameters: ammonium acetate concentration, pH, and percent methanol. The effect of the ammonium acetate concentration demonstrates that the electrolyte is required for efficient ionization and the ESIMS intensity was optimal at a concentration of 2mM for the selected compounds, except 2,4'-dinitrodiphenylamine. The aqueous solution pH, corresponding to the available protons in solution, did not have a significant effect on the ESIMS intensity of the analytes. The percent methanol was evaluated with both decreasing and constant electrolyte concentrations to demonstrate the effects of droplet stability and ion transfer into the gas phase. These findings were applied to the analysis of the selected smokeless powder additives using HPLC-ESIMS to illustrate increased sensitivity for the protonated molecules.  相似文献   
93.
There is evidence that the multinational corporation (MNC) and a developing nation may have a set of mutually beneficial goals. This article investigates the goals of the multinational corporation and the goals of a developing nation. It then illustrates the mutual benefits in terms of resource identification, and technology selection and development. A planning mechanism is suggested. Finally, some guide lines are offered that should enhance the probability of cooperation.  相似文献   
94.
95.
Political relationships often vary over time, but standard modelsignore temporal variation in regression relationships. We describea Bayesian model that treats the change point in a time seriesas a parameter to be estimated. In this model, inference forthe regression coefficients reflects prior uncertainty aboutthe location of the change point. Inferences about regressioncoefficients, unconditional on the change-point location, canbe obtained by simulation methods. The model is illustratedin an analysis of real wage growth in 18 OECD countries from1965–1992.  相似文献   
96.
Because of difficulties collecting sales taxes on Internet sales, several states have engaged in an effort (the Streamlined Sales Tax Project, SSTP) to simplify their sales tax systems. One hope among SSTP proponents is that a simplified system will result in Internet vendors voluntarily collecting the sales tax. We address two issues:
  • ? Will states adopt the extensive reforms proposed by the SSTP?
  • ? Will vendors voluntarily collect the sales tax?
We argue that states are unlikely to adopt extensive reforms, but if they did, many vendors would voluntarily collect sales taxes.  相似文献   
97.
98.
The Y-PLEX 12 system, developed for use in human identification, enables simultaneous amplification of eleven polymorphic short tandem repeat (STR) loci, namely DYS392, DYS390, DYS385 a/b, DYS393, DYS389I, DYS391, DYS389II, DYS 19, DYS439 and DYS438, residing on the Y chromosome and Amelogenin. Amelogenin provides results for gender identification and serves as internal control for PCR. The validation studies were performed according to the DNA Advisory Board's (DAB) Quality Assurance Standards. The minimal sensitivity of the Y-PLEX 12 system was 0.1 ng of male DNA. The mean stutter values ranged between 3.76-15.72%. A full male profile was observed in mixture samples containing 0.5 ng of male DNA and up to 400 ng of female DNA. Amelogenin did not adversely affect the amplification of Y-STRs in mixture samples containing male and female DNA. The primers for the Y-STR loci present in Y-PLEX 12 are specific for human DNA and some higher primates. None of the primate samples tested provided a complete profile at all 11 Y-STR loci amplified with the Y-PLEX 12 system. Y-PLEX 12 is a sensitive, valid, reliable, and robust multiplex system for forensic analysis, and it can be used in human forensic and male lineage identification cases.  相似文献   
99.
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   
100.
An unusual fatality secondary to oxycodone in a child is reported. A 2-year-old female child was conveyed to a local hospital after exhibiting signs of rubbing of the mouth and staggering. A hospital toxicological immunoassay screen for drugs of abuse and tricyclic antidepressants was performed on a urine sample and reported as negative. She was discharged and found unresponsive the next morning. She was conveyed to a second hospital in full cardiopulmonary arrest and despite resuscitative efforts, was pronounced dead upon arrival. An autopsy was performed and postmortem specimens were submitted and screened for drugs using mainly chromatographic techniques. Quantitation was achieved by gas chromatography with nitrogen phosphorus detection. Confirmation was performed by gas chromatography/mass spectrometry. Oxycodone was the only drug detected in the following concentrations: heart blood, 1.36 mg/L; gastric contents, 7.33 mg in 33 mL (222.34 mg/L); liver, 0.2 mg/kg; and urine, 47.23 mg/L (47,230 ng/mL). In addition, immunoassay testing of the urine was positive for the opiate class of drugs. This case report demonstrates an unusual cause of death in a young child with emphasis on potential limitation in hospital urine screening tests and the importance of complete forensic toxicological testing in all child deaths.  相似文献   
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