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131.
The elemental composition and postfiring residues of several "lead-free" or "nontoxic" centerfire handgun ammunition types currently available to the general public were examined. Offerings from Winchester, Remington/UMC, Federal and Speer were obtained from retail sources in both .45 ACP and 9 mm when possible. A total of 112 postfiring residue samples (SEM pins) were collected at varying distances from the muzzle, at two distances from target and from the shooter's hands. An additional 20 samples were collected by direct ignition of primers. Qualitative determinations were carried out using scanning electron microscopy (SEM)/electron dispersive spectrometry (EDS) analysis. All types tested contained aluminum (Al), silicon (Si), copper (Cu), and zinc (Zn). Most contain traces of sulfur and calcium. Winchester WinClean and Remington LeadLess contained potassium as the principle ingredient. Federal BallistClean contained barium, while Speer Lawman CleanFire contained strontium. In the main, these compared favorably with manufacturers' MSDS publications and patents granted. The characterizations undertaken here will be of use to the forensic electron microscopist as these formulations gain popularity.  相似文献   
132.
The Tri-State Crematory Incident in Nobel, GA (February 2001) revealed limitations in traditional human cremated remains (cremains) analytical methodology. The goal of this study was to develop a method for effectively classifying questionable sets of cremains as legitimate or contaminated. Eighty-eight samples of known human cremains, concrete, mixtures of the two, and questionable sets of cremains were acid digested and analyzed for 21 elements by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Variable cluster and principle component analyses identified the seven elements (Sb, B, Li, Mn, Sr, Tl, and V) used to develop discriminant functions to classify questionable sets into two groups: cremains and concrete. The discriminant analysis shows that at the 0.90 probability level, mixtures of 50% or less human content were classified as concrete. Mixtures with 90% human content classified as cremains. Sixty percent and 75% human content mixtures remained in the questionable classification, but as the concentration of human increased in the mixture, the probability of assignment to the known cremains group increased. Most of the questionable human samples classified as cremains. This is a pilot study and cannot yet satisfy Daubert standards for courtroom admissibility, but it indicates that it is possible to determine the legitimacy of cremains using elemental analysis by ICP-OES coupled with multivariate statistical analysis.  相似文献   
133.
Megaprojects are systems of highly concentrated power whose footprints, or radius of effects, are without precedent in human history. Once upon a time, even under imperial conditions, most people on our planet lived and loved, worked and played within geographically limited communities. They never had to reckon with all of humanity as a factor in their daily lives. Whenever they acted recklessly within their environment, for instance, they had the option of moving on, safe in the knowledge that there was plenty of Earth and not many others. Whenever bad things happened, they happened within limits. Their effects were local. The politics of megaprojects radically alters this equation; it poses new questions about the governance of risk and the nature and limits of democratic politics. The politics of megaprojects—put simply—raises fundamental questions about the ‘life and death of democracy’.  相似文献   
134.
Consultation of scientific evidence by policy actors has been the foci of attention of knowledge utilization scholars for decades. The present study questioned the extent to which randomized controlled trials (RCTs)—generally seen as the gold standard of scientific research—are known and consulted by policy analysts in ministerial settings. Using cross‐sectional data collected in 17 ministries in Québec (Canada), our study showed that fairly high levels of policy analysts report never having heard of RCTs, thus possibly hindering effective communication of scientific results to relevant policy makers. Statistical analyses reveal the importance of cognitive factors in explaining both phenomena.  相似文献   
135.
In the aftermath of the August 2011 riots, politicians and commentators offered a range of explanations for the social unrest and wanton violence. Drawing on survey and focus‐group data, this paper investigates those explanations by analysing how socio‐economic, normative and political factors shape contemporary attitudes towards law breaking in Britain. The paper finds that both economic deprivation and personal moral values help to explain attitudes toward illegal behaviour, but citizens’ mistrust of political leaders and their disengagement from public affairs are also an important factor. The findings suggest that politicians who want to provide moral leadership need to do so through their actions as well as their words.  相似文献   
136.
Budget transparency has come to be considered a key aspect of governance. Over the past decade, donors have invested increasing resources in strengthening processes through which budget transparency in developing countries can be enhanced. According to the 2008 Open Budget Index (OBI) Report, however, aid dependency and budget transparency appear to be inversely correlated. This article looks at the role of donor agencies in promoting or preventing budget transparency in aid‐dependent countries. It looks at significant correlations across the whole sample of 84 countries covered in the 2008 OBI, and analyzes more specific data for a sub‐sample of 16 aid‐dependent countries, before selecting six countries for which more detailed findings are then presented. All of these countries have implemented reforms aimed at enhancing budget transparency, with substantial donor support. These, however, often had only limited success, partly because they were not well adapted to the local context, and partly because donors put limited emphasis on improving public access to budget information. Donor efforts were also often offset by other characteristics of donor interventions, namely their fragmentation, lack of transparency, and limited use of programme aid modalities such as budget support and pooled sector funding. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
137.
The present study aims to contribute to the existing policy transfer research by examining the immature policy environments of post‐communist countries. To determine the main factors explaining the process of policy transfer, the establishment of probation systems in Estonia and Latvia is analyzed by applying a comparative case study design. The study demonstrates that timing is an important variable in the policy transfer in a transitional setting. A transitional context in itself is likely to lead to policy transfer because of urgent decision‐making needs, a shortage of domestic expertise and of financial resources. The process of policy transfer can be characterized as quite fortuitous: the choice of role models is limited to the existing or first contacts with foreign partners who are able to provide financial assistance. Improvement of administrative capacity is seen as a key factor in the shift from haphazard policy copying to responsible policy transfer. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
138.
This article provides a practical guide for improving the quality of evidence‐based policy. Rather than adopting an approach that gives priority to particular types of research methodologies, this paper argues that evidence drawn from any methodology will improve if standards of transparency and accountability are followed in the process of gathering, analysing, interpreting, and presenting evidence for policy. The papers details what these standards of transparency and accountability mean in practice, how these standards can be achieved, and possible limits to their adoption.  相似文献   
139.
Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films.  相似文献   
140.
Each digital camera has an intrinsic fingerprint that is unique to each camera. This device fingerprint can be extracted from an image and can be compared with a reference device fingerprint to determine the device origin. The complexity of the filters proposed to accomplish this is increasing. In this note, we use a relatively simple algorithm to extract the sensor noise from images. It has the advantages of being easy to implement and parallelize, and working faster than the wavelet filter that is common for this application. In addition, we compare the performance with a simple median filter and assess whether a previously proposed fingerprint enhancement technique improves results. Experiments are performed on approximately 7500 images originating from 69 cameras, and the results are compared with this often used wavelet filter. Despite the simplicity of the proposed method, the performance exceeds the common wavelet filter and reduces the time needed for the extraction.  相似文献   
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