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排序方式: 共有3866条查询结果,搜索用时 15 毫秒
961.
Research projects aimed at proposing fingerprint statistical models based on the likelihood ratio framework have shown that low quality finger impressions left on crime scenes may have significant evidential value. These impressions are currently either not recovered, considered to be of no value when first analyzed by fingerprint examiners, or lead to inconclusive results when compared to control prints. There are growing concerns within the fingerprint community that recovering and examining these low quality impressions will result in a significant increase of the workload of fingerprint units and ultimately of the number of backlogged cases. This study was designed to measure the number of impressions currently not recovered or not considered for examination, and to assess the usefulness of these impressions in terms of the number of additional detections that would result from their examination.  相似文献   
962.
In this paper we have adapted a technique, previously used to determine the presence of urea in aqueous samples of wine and urine, to detect trace levels of urea nitrate explosives. The procedure involves the reaction of the uronium ion (protonated urea) with a fluorophore, xanthydrol. By modification of the procedure to utilize non-aqueous reagents, in neutral conditions, it can be made specific to the presence of the urea nitrate ion pair. The procedure includes selective detection of derivatization products by UV and fluorescence following separation by High-Performance Liquid Chromatography (HPLC). Analytical method development included optimization of HPLC conditions (solvent, gradient), UV and fluorescence wavelengths, and derivatization parameters (xanthydrol amount, reaction times, temperature). The extraction of urea nitrate from surfaces was also investigated and optimized. For best quantification, it was shown that an internal standard was required; this resulted in a quantification limit around 0.17mM (21mg/L). The entire procedure could be performed in less than 30min per sample and potential interferences such as ammonium, nitrate, and urea did not produce a response under standard conditions.  相似文献   
963.
The entities responsible for isolated vaginal bleeding are a broad spectrum of diseases. Vaginal bleeding in a prepubertal child is always treated as an alarming symptom both by parents and professionals. Most often, one of the first hypotheses is that a sexual abuse may be occurred and the clinical work up is oriented to explore it and eventually confirm or substantiante another diagnosis. Among the possible differential diagnosis urethral prolapse has to be considered. We report the case of a 6 years-old Caucasian girl referred to our Service for a mild vaginal bleeding and with the suspicion of sexual abuse, excluded after the confirmation of the presence of urethral prolapse. The clinical picture and workup are described and compared with a review of the international literature on the issue.  相似文献   
964.
Infectious diseases are a long-standing and continuing threat to health and welfare, with their containment dependent on national disease surveillance and response capacities. This article discusses infectious disease surveillance in the United States and the United Kingdom, examining historical national traditions for identifying and controlling infectious disease risks and how globalization and technical advances have influenced the evolution of their respective approaches. The two systems developed in different but parallel ways. In the United States, surveillance remained quite localized at the state level until the early twentieth century and still retains many of those features. The U.K. approach became centralized from the latter part of the nineteenth century and has principally remained so. In both cases, disease surveillance was traditionally conceived as a public good, where national or local authorities held sovereign rights and power to protect public health. With the increasing globalized nature of infectious disease, such notions shifted toward surveillance as a global public good, with countries responding in turn by creating new global health governance arrangements and regulations. However, the limitations of current surveillance systems and the strong hold of national interests place into question the provision of surveillance as a global public good. These issues are further highlighted with the introduction of new surveillance technologies, which offer opportunities for improved disease detection and identification but also create potential tensions between individual rights, corporate profit, equitable access to technology, and national and global public goods.  相似文献   
965.
Bone marrow (BM) analysis is of forensic interest in postmortem toxicological investigation in case of limited, unavailable or unusable blood samples. However, it remains difficult to determine whether a drug BM concentration is therapeutic or represents overdose, due to the lack of studies on this alternative matrix. Given the variations in BM composition in the body, sample location was suggested to be a relevant factor in assessing BM concentration. The aim of the present study was to compare postmortem caffeine concentrations in various BM sample locations and secondly to consider the correlation between BM and blood concentrations. Six BM samples (right and left side: proximal and medial femur and 5th rib) and a blood sample were collected from 21 forensic autopsies. Gas chromatography coupled to tandem mass spectrometry was performed. Blood caffeine concentrations ranged from 60 to 7591ng/mL. Femoral and rib BM concentrations ranged from 51 to 6171ng/g and 66 to 7280ng/g, respectively. Blood concentrations were always higher than BM concentrations. As a good correlation was demonstrated between blood and rib BM and between blood and the average of the four femoral BM concentrations, blood caffeine concentrations could be correctly extrapolated from BM concentrations. BM caffeine concentration was found to depend on sample location. Rib BM caffeine concentrations appeared to be systematically greater than averaged femur values and concentrations were much more variable between the 4 femur BM samples than between the 2 ribs. From a practical point of view, for caffeine analysis, rib BM appeared more relevant than femoral BM, which requires multisampling to overcome the concentration variability problem.  相似文献   
966.
Several ink dating methods based on solvents analysis using gas chromatography/mass spectrometry (GC/MS) were proposed in the last decades. These methods follow the drying of solvents from ballpoint pen inks on paper and seem very promising. However, several questions arose over the last few years among questioned documents examiners regarding the transparency and reproducibility of the proposed techniques. These questions should be carefully studied for accurate and ethical application of this methodology in casework. Inspired by a real investigation involving ink dating, the present paper discusses this particular issue throughout four main topics: aging processes, dating methods, validation procedures and data interpretation. This work presents a wide picture of the ink dating field, warns about potential shortcomings and also proposes some solutions to avoid reporting errors in court.  相似文献   
967.
In undergraduate medical education, the training of post-mortem external examination on dead bodies might evoke strong emotional reactions in medical students that could counteract the intended learning goals. We evaluated student perception of a forensic medicine course, their perceived learning outcome (via self-assessment) and possible tutor-dependent influences on the overall evaluation of the course by a questionnaire-based survey among 150 medical students in Hamburg, Germany. The majority of students identified post-mortem external examination as an important learning objective in undergraduate medical education and did not feel that the dignity of the deceased was offended by the course procedures. After the course, more than 70% of the students felt able to perform an external examination and to fill in a death certificate. Respectful behavior of course tutors towards the deceased entailed better overall course ratings by students (p<0.001). Our findings highlight the importance of factors such as clearly defined learning goals and course standardization (formal curriculum) as well as tutor behavior (informal curriculum) in undergraduate education in forensic medicine. Furthermore, we suggest embedding teaching in forensic medicine in longitudinal curricula on death and dying and on the health consequences of interpersonal violence.  相似文献   
968.
The purpose of this study was to examine the nature and extent of mutual violence among a sample of pregnant and parenting Latina adolescent females and their partners. The sample consisted of 73 Latina adolescent females between the ages of 14 and 20 who were referred to a community-based organization for case management, education, and psychosocial support for pregnant and parenting adolescents. They completed the Conflict Tactics Scale (CTS-2) as part of a pretest to evaluate this intervention program. A small number (12 out of 73; 16%) reported no use of aggressive conflict tactics. Eighty-four percent (61 out of 73) of the study respondents reported using at least one form of minor psychological aggression and 62% (45 out of 73) reported using at least one form of minor physical assault over the past 6 months. Mutuality of conflict was high, especially in cases of minor assault by partner. There was no difference in severity or chronicity of conflict between those who were pregnant and those who were not. Female respondents reported that they and their partners engaged in comparable levels of sexual coercion. Discussion of the context of psychological, physical, and sexual aggression in adolescent relationships suggests alternative approaches to prevention of intimate partner violence among adolescents.  相似文献   
969.
This article examines the development of Ireland's abortion policy from 1861 to the present day. It explores the reasoning for this policy as well as the inherent problems with this policy. It examines in detail the A, B and C v. Ireland judgement and its impact, (if any) on Irish abortion law. Finally, it discusses the margin of appreciation doctrine used by the European Court of Human Rights in deciding cases of a moral nature.  相似文献   
970.
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