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861.
Seven ethyl homologues of known tropane esters have recently been detected as impurities in the gas chromatographic signature profiles of authentic Peruvian illicit cocaine base and hydrochloride exhibits. Peruvian cocaine base processors are now known to use ethanol for the purification of crude cocaine base. This process is referred to as the "base lavada" or "washed base" process and is a recent substitute method for the potassium permanganate oxidation purification methodology. Seven ethyl ester homologues were formed in illicit cocaine from the transesterification of known tropane methyl esters or possibly ethyl esterification of their respective tropane C-2 carboxylic acids in the presence of ethanol. Exhibits containing these compounds were subjected to gas chromatographic-mass spectrometric analyses to determine their identity and were subsequently synthesized to verify their structures. Quantitative determinations were obtained from ion-pair chromatography isolation followed by gas chromatography with flame ionization detection. Specifically, hexanoylecgonine ethyl ester, cocaethylene, cis-cinnamoylecgonine ethyl ester, trans-cinnamoylecgonine ethyl ester, 3',4',5'-trimethoxybenzoylecgonine ethyl ester, cis-3',4',5'-trimethoxycinnamoylecgonine ethyl ester, and trans-3',4',5'-trimethoxycinnamoylecgonine ethyl ester were detected and characterized. When present, these compounds were detected at levels ranging from 8.6 x 10(-4) to 9.3 x 10(-1)% relative to cocaine. 相似文献
862.
Sergio Cardoso Ph.D. María T. Zarrabeitia Ph.D. Laura Valverde B.Sc. Adrian Odriozola B.Sc. Miguel Á. Alfonso‐Sánchez Ph.D. Marian M. De Pancorbo Ph.D. 《Journal of forensic sciences》2010,55(5):1196-1201
Abstract: In this study, we analyzed the entire mtDNA control region in 61 unrelated individuals from the Pas Valley (Cantabria), a human isolate from northern Spain, to evaluate the suitability of this analysis to increase the power of discrimination of this locus for forensic purposes in human isolates. Low values obtained for the diversity parameters confirmed the relative isolation of this human group. The main findings of this study indicated that even the analysis of the entire mtDNA control region may have important limitations for use in forensic casework when dealing with human isolates: none of the 44 individuals who exhibited identical HVI‐HVII haplotypes could be further differentiated by analysis of segment HVIII. Nevertheless, analysis of the entire mtDNA control region proved to be useful to determine the ancestry of the samples examined, by contributing to the confirmation, and, on occasion, even to the refinement of the haplogroup assignment. 相似文献
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866.
This article offers a reformulation of the concept of professionalism as it applies to public sector decision making. After critically evaluating existing work, we present a role theoretic model of public sector decision making that provides a precise conceptual and operational meaning to the term professionalism. We then evaluate the model's applicability to public sector actors, using city managers as an example. Finally, we discuss some of the public policy implications of increasing public service professionalization. 相似文献
867.
868.
Adair TW DeLong L Dobersen MJ Sanamo S Young R Oliver B Rotter T 《Journal of forensic sciences》2003,48(5):1113-1116
We present an unusual case in which an adult female committed suicide by fire while enclosed in the trunk of her vehicle. A finding of suicide was reached only because several key investigative facts were uncovered. Without these discoveries the case may still remain open as a suspicious death. Fire is rarely used as a mechanism of suicide in Western culture, and, as such, similar cases should be reported to advance our recognition of this phenomenon. 相似文献
869.
870.
In December 2002, approximately 250 lbs. of ground beef was adulterated with nicotine sulfate by a supermarket employee and subsequently sold to the public. Soon afterward, reports of illness associated with ground beef purchased at a single store were identified. Authorities suspected the ground beef was tainted with Black Leaf 40, a banned pesticide containing approximately 40% nicotine as nicotine sulfate. Ground beef submitted to our laboratory was analyzed in concert by high performance liquid chromatography-ultraviolet detection (HPLC-UV), gas chromatography-mass spectrometry (GC-MS), and high performance anion exchange chromatography with suppressed conductivity detection. GC-MS was used to identify the samples that contained nicotine. The nicotine was confirmed and quantitated by HPLC-UV. The sulfate was identified and quantitated by high performance anion exchange chromatography with suppressed conductivity detection. Our analysis revealed that the raw tainted beef contained about 350 mg/kg nicotine free base, a potentially lethal dose of nicotine per serving for an adult. Additionally, we found elevated sulfate levels in the samples that tested positive for nicotine, providing evidence that nicotine sulfate was the probable adulterant. 相似文献