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61.
In forensic laboratories, increased extraction efficiency of trace evidence is paramount because analytical success is intrinsically dependent on the quantity of DNA recovered. Moreover, highly concentrated nucleic acids are vital for effective downstream analysis and high quality results. This study investigated the efficiency of extraction with the Qiagen® QIAamp® DNA Investigator kit, and explored improvements to the methodology that would maximise the recovery of low concentration forensic samples. Controlled amounts of starting cellular material were used to mimic trace (or low level) DNA deposits prior to DNA extraction with the Investigator kit. Addition of the provided carrier RNA along with conducting two successive elutions of 50 µL improved the net recovery of DNA to 95%. Concentration with centrifugal filters post-extraction were able to concentrate DNA but a large net loss was observed. For the concentration of historic, retrospectively extracted DNA, centrifugal methods are able to concentrate DNA extracts previously too dilute for analysis. These concentrated volumes, however are small, allowing for minimal downstream analysis attempts before the sample is exhausted. 相似文献
62.
AbstractExisting political theory, particularly which deals with justice and/or rights, has long assumed citizenship as a core concept. Noncitizenship, if it is considered at all, is generally defined merely as the negation or deprivation of citizenship. As such, it is difficult to examine successfully the status of noncitizens, obligations towards them, and the nature of their role in political systems. This article addresses this critical gap by defining the theoretical problem that noncitizenship presents and demonstrating why it is an urgent concern. It surveys the contributions to the special issue for which the article is an introduction, drawing on cross-cutting themes and debates to highlight the importance of theorising noncitizenship due to both the problematic gap that exists in the theoretical literature, and the real world problems created as a result of noncitizenship which are not currently successfully addressed. Finally, the article discusses key future directions for the theorisation of noncitizenship. 相似文献
63.
The effects of changes in the minimum drinking ages in various North American jurisdictions are reviewed. The research suggests that although most teenagers have experimented with alcohol, the rates of alcohol consumption and alcohol-related traffic collisions can be increased and decreased with the drinking age control legislation. 相似文献
64.
65.
The application of infrared chemical imaging to the analysis of bicomponent fibers was evaluated. Eleven nominally bicomponent fibers were examined either side-on or in cross-section. In six of the 11 samples, infrared chemical imaging was able to spatially resolve two spectroscopically distinct regions when the fibers were examined side-on. As well as yielding characteristic infrared spectra of each component, the technique also provided images that clearly illustrated the side-by-side configuration of these components in the fiber. In one case it was possible to prepare and image a cross-section of the fiber, but in general the preparation of fiber cross-sections proved very difficult. In five of the 11 samples, the infrared spectra could be used to identify the overall chemical composition of the fibers, according to a published classification scheme, but the fiber components could not be spatially resolved. Difficulties that are inherent to conventional "single-point" infrared spectroscopy, such as interference fringing and sloping baselines, particularly when analyzing acrylic type fibers, were also encountered in the infrared chemical image analysis of bicomponent fibers. A number of infrared sampling techniques were investigated to overcome these problems, and recommendations for the best sampling technique are given. Chemical imaging results were compared with those obtained using conventional fiber microscopy techniques. 相似文献
66.
The relative importance of procedural and distributive factors for satisfaction was tested in a field study of 71 couples who were randomly assigned to mediate or litigate their child custody dispute. Multiple regression analyses showed that procedural factors (decision control and respect) and distributive factors (feeling of winning what one wanted) were equally influential for parents' satisfaction as a group. However, the relative importance of procedural fairness and outcome favorability differed depending on disputant gender, favorability of outcomes, and level of conflict in the relationship. Support was found for Tyler's (1989) assertion that the specific procedural factor of decision control is especially important in dispute resolution settings. However, contrary to expectation, decision control was relatively more important to satisfaction in mediation than in litigation. It is suggested that the type of allocation setting may not be as influential for satisfaction as participants' status in the proceedings and their perceptions of the level of conflict. 相似文献
67.
EDA for HLM: Visualization when Probabilistic Inference Fails 总被引:1,自引:1,他引:0
e-mail: jwbowers{at}umich.edu (corresponding author) e-mail: kwdrake{at}umich.edu Nearly all hierarchical linear models presented to politicalscience audiences are estimated using maximum likelihood undera repeated sampling interpretation of the results of hypothesistests. Maximum likelihood estimators have excellent asymptoticproperties but less than ideal small sample properties. Multilevelmodels common in political science have relatively large samplesof units like individuals nested within relatively small samplesof units like countries. Often these level-2 samples will beso small as to make inference about level-2 effects uninterpretablein the likelihood framework from which they were estimated.When analysts do not have enough data to make a compelling argumentfor repeated sampling based probabilistic inference, we showhow visualization can be a useful way of allowing scientificprogress to continue despite lack of fit between research designand asymptotic properties of maximum likelihood estimators. 相似文献
68.
Ellena KR 《Journal of law and medicine》2005,13(1):106-124
The introduction of a treaty between Australia and New Zealand to regulate complementary and alternative medicines (CAM) has revived the age-old debate between advocates of conventional medicine and those of CAM, particularly with regard to the standards of regulation that should be applied. Currently, the systems for regulating CAM products in Australia and New Zealand are very different, making harmonisation contentious, as the proposed treaty follows the Australian system very closely. New Zealand and Australian principles of good regulatory practice stipulate that only minimum necessary standards should be imposed, and should be transparent, understandable and equitable. It is argued that the proposed treaty does not adhere to good regulatory standards, and that other forms of harmonisation should be sought to avoid adopting a regulatory regime in New Zealand that is overly restrictive and harmful to the New Zealand CAM industry. 相似文献
69.
Relying on rarely analyzed public opinion data from the 1930s and early 1940s, we take issue with the notion popular in contemporary
liberal circles that the New Deal era represented a period of expansive commitment to the security and well-being of the poor
and politically disenfranchised. At least where the public is concerned—as opposed to the progressive policy makers in the
Roosevelt administration—the jobless were regarded with suspicion, immigrants should be forced to “go home,” women belong
in the kitchen not on the shop floor. The harsher the economic conditions (by state), the more conservative were the public
attitudes. Hence New Deal legislative victories accrued despite rather than because of public support.
相似文献
Elisabeth JacobsEmail: |
70.
The concept of community standards is the cornerstone of advertising self‐regulation in Australia. However, there is a dearth of research on current attitudes towards advertising and a virtual absence of such data in an Australian context. A questionnaire was developed to assess consumer attitudes towards advertising; respondents were 872 adults residing in New South Wales. We found high levels of concern regarding advertising standards in general and a consistent perception that advertising should not, for example, use coarse language or violent images, portray women or men as sex objects or show nudity, stereotype or make fun of groups of people, or convey messages that undermine parental authority. In relation to specific appeals and executional elements, although we identified numerous statistically significant demographic differences, there was a clear majority view as to what elements are unacceptable. That is, rather than the posited vocal ‘moral minority’, there is a consistency of views across the community on key issues of advertising standards. The finding that only a very small proportion of community‐based respondents knew how to make a complaint to the correct organisation suggests that studies utilising complainant samples are unlikely to be representative of those who are concerned about advertising. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献