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131.
Child-sized pig carcasses (Sus scrofa) were placed in surface deposit and buried scenarios in a wooded area of Virginia from May 1998 through December 2000, to examine the taphonomic effects of decompositional changes, predator scavenging, and the extent of remains scattering. Changes were observed through on-site examination, charting of remains, and recorded video imaging. Analysis of data revealed that utilization of corpses as food sources by vertebrates was dependent upon invertebrate colonization. Vertebrates avoided feeding on the corpses while invertebrate colonization was active, and would feed before invertebrates successfully colonized a corpse, or would wait until the invertebrate populations migrated away from the corpse. Among vertebrates, there was no apparent succession order for the animals utilizing the remains as a food source. Different vertebrates would feed at different times based upon diurnal or nocturnal predilection. Analysis noted an accidental cooperative relationship between the invertebrates and vertebrates scavenging on the corpses. Certain vertebrates gained access to the internal tissues by utilizing openings in the corpses caused by invertebrate and other vertebrate scavenging. Alternately, carrion-frequenting insects were afforded access to previously inaccessible colonization sites as a result of scavenging vertebrate activities.  相似文献   
132.
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   
133.
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   
134.
固相萃取法(Sep-PakC18小柱)同时萃取净化生物检材(血浆、尿)中的甲醚菊酯、灭扫利、功夫、二氯苯醚菊酯、安绿宝、速灭杀丁和敌杀死。通过气相色谱氢焰检测器、非极性熔融石英大口径毛细管柱及程序升温色谱条件,得到较好的系统分离,并测定萃取回收率在81%~93%(血浆)和90%~102%之间(尿)。实验证明,用70%甲醇稀释检材并用氯仿洗脱可得到较完全的吸附和最佳回收率。  相似文献   
135.
The discrimination of noncolored transparent polyethylene bags was studied by several nondestructive and semidestructive analytical methods. X-ray diffraction, infrared spectroscopy, and optical microscopy (differential interference contrast microscopy and phase contrast microscopy) were applied to polyethylene films. X-ray diffraction was used to distinguish variations in the crystalline phase, infrared spectroscopy was used to distinguish variations in the molecular components, and optical microscopy was used to distinguish the different surface morphologies. The results show that X-ray diffraction classifies the crystalline phase of the film depending on whether it is made from low-density polyethylene, linear low-density polyethylene, or high-density polyethylene; that infrared spectroscopy is useful to distinguish the molecular components and it is the most discriminating technique; and that optical microscopy discriminate films easily by their morphological differences.  相似文献   
136.
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   
137.
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   
138.
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   
139.
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   
140.
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   
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