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851.
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
852.
Grinage BD 《Journal of forensic sciences》2003,48(4):861-868
This article discusses psychiatry's limited conceptualization of volitional capacity and its application to sexually violent predator laws by exploring two legal opinions critical to predator case law (Kansas v. Hendricks and Kansas v. Crane). The author reviewed pertinent psychiatric literature on impaired volition to identify potential contributions and limitations that psychiatry may offer the legal field. Assessment of the ego dystonic nature of impaired self-regulation, utilization of recent advances in self-assessment and laboratory evaluation of impulsive behavior, and dimensional categorization of a volitional capacity construct are recommended as an approach to the assessment and understanding of an inability to control concept. This paper concludes that elements of volition may be psychiatrically evaluated in a way that contributes to the Court's understanding of that capacity. However, further study is needed to operationally define volitional capacity and address issues of assessment validity and reliability. 相似文献
853.
LaPorte GM Wilson JD Mancke SA Payne JA Ramotowski RS Fortunato SL 《Journal of forensic sciences》2003,48(5):1163-1171
Thermal transfer printing refers to printing processes that utilize heat to produce an image by either physical or chemical means or by a combination of both. As the technology has improved and the supplies have become less expensive, the use of thermal printing in the personal and business markets has increased significantly. Specifically, dye diffusion thermal transfer and thermal mass transfer have become predominant in the production of counterfeit credit cards, drivers' licenses, and other types of documents produced on plastic media. Chemical analysis by means of thin layer chromatography (TLC) has proven to be useful in characterizing various types of inks (e.g., writing and inkjet inks). In this study, the authors examined 81 different samples that included a total of 54 printer samples (43 photographic prints on paper and eleven plastic card samples) and 27 printer ribbons. A new TLC method was developed and tested utilizing a solvent system (80% n-hexane, 3% methyl ethyl ketone, and 17% ethyl acetate) that is capable of producing excellent resolution. 相似文献
854.
855.
Gruszecki AC Kloda S Simmons GT Daly TM Hardy RW Robinson CA 《Journal of forensic sciences》2003,48(2):432-434
A 29-year old female with a history of depression was found dead in a hotel room. The death scene investigation found empty pill bottles and an empty liter bottle of wine. Metaxalone, a centrally acting muscle relaxant, along with citalopram, ethanol, and chlorpheniramine were identified in the postmortem samples and quantitated by gas chromatography-mass spectrometry. The concentration of metaxalone in femoral vein blood was 39 mg/L. The heart blood concentration was 54 mg/L. Femoral vein blood concentrations of citalopram and chlorpheniramine were 0.77 mg/L and 0.04 mg/L, respectively. Ethanol levels were 0.13 g/dL in vitreous and 0.08 g/dL in heart blood. Other tissue samples were also analyzed. The authors consider the metaxalone concentrations toxic and potentially fatal. The citalopram concentrations were lower than those reported in fatal cases for this drug alone. Death was ascribed to polydrug abuse/overdose with metaxalone a major contributor. This represents the first reported case to our knowledge in which a metaxalone overdose significantly contributed to death. 相似文献
856.
This study was conducted in an attempt to develop a metallographic method for the investigation of pipe bombings. Three common pipe materials, ASTM A53 steel, AISI 304L stainless steel, and 6061-T6 aluminum, were shock-loaded using five high explosives and three propellants. The explosives used were ANFO, Composition C4, C6 detasheet, nitroglycerine-based dynamite, and flake TNT. The propellants used were FFFFg black powder. Red Dot smokeless powder, and Turbo Fuel A. The post-blast microstructure, hardness, and, in the case of 304L, transformed martensite content were examined for each test. The damage done to the microstructure was found to increase with increasing detonation velocity of the explosives and increase in pressure generated by the shock-metal interaction. Material hardness and, in the case of 304L, martensite content showed a sharp increase followed by a plateau as the shock pressure and detonation velocity increased. 相似文献
857.
858.
Introduction
Introduction to special issue on professional insecurities 相似文献859.
Commentary
Commentaries on Brunner and Willards professional insecurities 相似文献860.
Scholars of legislative studies typically use ideal point estimatesfrom scaling procedures to test theories of legislative politics.We contend that theory and methods may be better integratedby directly incorporating maintained and to be tested hypothesesin the statistical model used to estimate legislator preferences.In this view of theory and estimation, formal modeling (1) providesauxiliary assumptions that serve as constraints in the estimationprocess, and (2) generates testable predictions. The estimationand hypothesis testing procedure uses roll call data to evaluatethe validity of theoretically derived to be tested hypothesesin a world where maintained hypotheses are presumed true. Wearticulate the approach using the language of statistical inference(both frequentist and Bayesian). The approach is demonstratedin analyses of the well-studied Powell amendment to the federalaid-to-education bill in the 84th House and the Compromise of1790 in the 1st House. 相似文献