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81.
The current backlog of casework is among the most significant challenges facing crime laboratories at this time. While the development of next-generation microchip-based technology for expedited forensic casework analysis offers one solution to this problem, this will require the adaptation of manual, large-volume, benchtop chemistry to small volume microfluidic devices. Analysis of evidentiary materials from rape kits where semen or sperm cells are commonly found represents a unique set of challenges for on-chip cell lysis and DNA extraction that must be addressed for successful application. The work presented here details the development of a microdevice capable of DNA extraction directly from sperm cells for application to the analysis of sexual assault evidence. A variety of chemical lysing agents are assessed for inclusion in the extraction protocol and a method for DNA purification from sperm cells is described. Suitability of the extracted DNA for short tandem repeat (STR) analysis is assessed and genetic profiles shown. Finally, on-chip cell lysis methods are evaluated, with results from fluorescence visualization of cell rupture and DNA extraction from an integrated cell lysis and purification with subsequent STR amplification presented. A method for on-chip cell lysis and DNA purification is described, with considerations toward inclusion in an integrated microdevice capable of both differential cell sorting and DNA extraction. The results of this work demonstrate the feasibility of incorporating microchip-based cell lysis and DNA extraction into forensic casework analysis.  相似文献   
82.
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   
83.
This article details the stability of Delta(9)-tetrahydrocannabinol (THC) in oral fluid during collection, extraction and storage. Oral fluid is being increasingly used as the specimen of choice for the detection of drug use in various applications. Studies to determine the extraction efficiency of THC from the collection buffer and stability under various laboratory storage conditions were carried out. THC was extracted from the collection pad and buffer with an average efficiency over 80% and was stable in Quantisal oral fluid extraction buffer when stored at refrigerated temperatures. Fluorescent lighting caused THC losses of over 50%, however the presence of the pad reduced the loss. In the dark, the loss of THC at room temperature was approximately 20% over 14 days. When stored with the serum separators in place, THC losses were significant. After 3 days, THC concentration was reduced by almost 30%, and after 14 days, 60% of the drug was lost and the losses were not concentration dependent.  相似文献   
84.
A rapid urinalysis system based on SPE-LC-MS/MS with an in-house post-analysis data management system has been developed for the simultaneous identification and semi-quantitation of opiates (morphine, codeine), methadone, amphetamines (amphetamine, methylamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA)), 11-benzodiazepines or their metabolites and ketamine. The urine samples are subjected to automated solid phase extraction prior to analysis by LC-MS (Finnigan Surveyor LC connected to a Finnigan LCQ Advantage) fitted with an Alltech Rocket Platinum EPS C-18 column. With a single point calibration at the cut-off concentration for each analyte, simultaneous identification and semi-quantitation for the above mentioned drugs can be achieved in a 10 min run per urine sample. A computer macro-program package was developed to automatically retrieve appropriate data from the analytical data files, compare results with preset values (such as cut-off concentrations, MS matching scores) of each drug being analyzed and generate user-defined Excel reports to indicate all positive and negative results in batch-wise manner for ease of checking. The final analytical results are automatically copied into an Access database for report generation purposes. Through the use of automation in sample preparation, simultaneous identification and semi-quantitation by LC-MS/MS and a tailored made post-analysis data management system, this new urinalysis system significantly improves the quality of results, reduces the post-data treatment time, error due to data transfer and is suitable for high-throughput laboratory in batch-wise operation.  相似文献   
85.
The case of seven urine samples collected for anti-doping purposes during a cycling stage race with moderately elevated testosterone and epitestosterone ratio (T/E) is reported. The very low probability of having all seven urine samples with such similar elevated T/E ratio (from 3.2 to 4.7) was very suspicious. Different pattern classification tools were tested to categorize the most similar steroid profiles, but none of the models enabled a clear classification of the different urine samples. Subsequently, genetic profiling of all urine samples was performed and demonstrated that three of the seven samples were collected from the same cyclist. Finally, the International Federation confirmed DNA profiling results. This suggests that urinary steroid data using several methodologies are not appropriate for identification purposes and to an extent not unique to individuals.  相似文献   
86.
Conclusion This paper has attempted to analyze the effect of the development of the financial sector, as reflected by the extent of financial deepening, in the economic development of countries. The Theoretical framework integrating financial growth to real growth is basically an adaptation of the Gurley-Shaw theory of finance in the development context, but with emphasis placed upon the supply-leading role of the financial sector. The empirical results of this study although not conclusive, indicate that financial deepening leads to a higher rate of capital accumulation and a higher level of per capita income. The lack of definitiveness of our evidence in support of the financial theory of economic development is due to a lack of comparable data on financial institutions, other than banks, for the different countries. Thus, although our study lends support to the supply-leading thesis, further judgement of the thesis must await more detailed empirical analyses.  相似文献   
87.
The period of 1914–1918 was a time of immense change for women in Britain. The Suffragist movement, begun in 1867, gained irresistible force, culminating in the Act of 1918 in which women were given the vote at thirty and men at twenty-one. It was not until the 1928 Act that for the first time in the history of Britain there was full adult suffrage, granting the vote to both sexes at twenty-one. The picture is a complex one; Mrs Pankhurst and her daughter Christabel identified their movement with the war effort, indeed their pre-war militancy became militarism. Mrs Fawcett, an avowed non-militant suffragist before the war, who believed in the verbal power of argument over revolutionary tactics, also supported the war effort and nationalism. However, there were other suffragists such as Sylvia Pankhurst, Emily Hobhouse, Catherine Marshall, Helena Swanwick, Olive Schreiner and Kate Courtney, who were opposed to the war. Mrs Pankhurst believed if women couldn't fight, they shouldn't vote. The pacifists believed that this view simply gave in to the argument for physical force. They also saw militarism as yet another version of the strong oppressing the weak and thus an emphatic form of patriarchy. However, although the suffragists were bitterly divided in their moral view of the war, they were united in the cause of women's emancipation.The war itself provided all classes of women with important opportunities to work outside the home, as munition workers, land-army workers, police-women, doctors and nurses. The experience of change caused by the suffrage movement, together with the effect of the war upon women's lives, transformed women's image of themselves in radical and irreversible ways.My paper draws on some 125 poems by 72 women poets; Scars Upon My Heart is the first anthology of its kind and testifies to women's involvement in the war and the impact it had upon their lives. The anthology is necessary reading, together with the soldier poets like Owen, Sassoon, Blunden and Rosenberg, whose war poetry has been known to us for the past sixty years, for a full understanding of the significance of war for women and men.  相似文献   
88.
89.
Most social justice critiques of medical care focus upon the allocation of extant, but scarce, resources. In contrast to that focus, this article explores the preallocative arena of factors which shape the supply and availability of medical care. We identify four such factors: (1)medicalization — the tendency to regard as biologically caused various human problems which were in earlier eras ignored or attributed to other causes; (2)social inclusion — the bringing of economically deprived and socially marginal groups into participation in the medical care system; (3)biomedical transcendence — the elevation of biomedically derived concepts of human function into a social and personal world view; and (4)health absolutism — the ideology which holds individuals accountable for their own health and which, contrary to the thrust of the other factors, deemphasizes access and social equity for professionally provided medical care. While these forces all enhance the place of health as a social value, it is by no means certain that they will lead to a society which is more medically just. The article concludes with an appeal for critical analysis of the processes which shape both the medical care system and the broad social concern with medical care.  相似文献   
90.
Initial reports of domestic violence are generally made to law enforcement officers who must respond and intervene. A subset of these episodes involves cases in which the victim, and, in many instances her child(ren), have been taken hostage by her husband or partner. Moreover, there are indications that the number of such incidents is growing. The purpose of this project was twofold: (1) to provide one of the first reports on the prevalence and characteristics of these events, and (2) to more closely analyze domestic crisis (hostage) situations using actual case examples. All information was obtained from the Hostage Barricade Database System (HOBAS) of the FBIs Crisis Negotiation Unit. HOBAS is a postincident information collection tool which stores historical data from law enforcement agencies across the nation on hostage/barricade incidents. An examination of this database yielded different types of domestic hostage-taking acts and outcomes (e.g., tactical vs. negotiated resolutions, survival vs. death/injury of perpetrator and/or victim[s]). Implications of the findings, for future crisis negotiation efforts directed toward nonviolent resolution of these high-risk critical incidents, are discussed.  相似文献   
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