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51.
The application of isotopic techniques to investigations requiring the provision of evidence to a Court is limited. The objective of this research was to investigate the application of light stable isotopes and isotope ratio mass spectrometry (IRMS) to solve complex forensic cases by providing a level of discrimination not achievable utilising traditional forensic techniques.Due to the current threat of organic peroxide explosives, such as triacetone triperoxide (TATP), research was undertaken to determine the potential of IRMS to differentiate samples of TATP that had been manufactured utilising different starting materials and/or manufacturing processes. In addition, due to the prevalence of pentaerythritoltetranitrate (PETN) in detonators, detonating cord, and boosters, the potential of the IRMS technique to differentiate PETN samples from different sources was also investigated.Carbon isotope values were measured in fourteen TATP samples, with three definite groups appearing in the initial sample set based on the carbon data alone. Four additional TATP samples (in a second set of samples) were distinguishable utilising the carbon and hydrogen isotopic compositions individually, and also in combination with the oxygen isotope values. The 3D plot of the carbon, oxygen and hydrogen data demonstrated the clear discrimination of the four samples of TATP. The carbon and nitrogen isotope values measured from fifteen PETN samples, allowed samples from different sources to be readily discriminated.This paper demonstrates the successful application of IRMS to the analysis of explosives of forensic interest to assist in discriminating samples from different sources. This research represents a preliminary evaluation of the IRMS technique for the measurement of stable isotope values in TATP and PETN samples, and supports the dedication of resources for a full evaluation of this application in order to achieve Court reportable IRMS results.  相似文献   
52.
Crime prevention is an activity that, sooner or later, requires the concourse of science. But the dictates of science may not mesh well with the social, institutional and political considerations that are persistent and powerful determinants of collective action. To the extent that they are ignored, crime prevention is less scientific and more pragmatic. Using a marketing metaphor, this paper examines selected aspects of the supply of and demand for scientific crime prevention in Canada and Venezuela from 1949 to the present. In both countries, academic entrepreneurs are revealed to be a necessary factor in the sale of crime prevention to government. On the demand side, governments adopt and adapt crime prevention policies in relation to their broader perspective on social problems and social change. However, rising crime rates and climates of urgency reduce the attractiveness of crime prevention. Scientific crime prevention is easier to sell when crime rates are stable or declining.  相似文献   
53.
Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes.  相似文献   
54.
Telecommunications regulation has experienced a fundamentalshift from rate regulation to increased reliance on compelledaccess, perhaps best exemplified by the Telecommunications Actof 1996's imposition of no fewer than four new access requirements.Unfortunately, each access requirement is governed by a separateset of rules for determining both the scope and the price ofaccess. The resulting ad hoc regime has created difficult definitionalproblems and opportunities for regulatory arbitrage. In thisarticle we propose a system inspired by the discipline of mathematicsknown as graph theory that integrates all of the different formsof access into a single analytical framework. This system separatesdifferent access regimes into five categories: (1) retail access,(2) wholesale access, (3) interconnection access, (4) platformaccess, and (5) unbundled access. It also provides insightsinto how each type of access complicates the already difficultproblems of network configuration and management and introducesinefficient biases into decisions about network capacity anddesign. The approach we propose also provides insights intothe transaction cost implications of the different types ofaccess. Drawing on the Coasean theory of the firm, our approachexamines the tradeoffs between internal governance costs andthe external transaction costs of providing access to offera theory of network boundaries. This framework shows how accessregulation distorts networks' natural boundaries and providesa basis for evaluating whether private ordering through marketswould lead to more efficient network design.  相似文献   
55.
Despite the recent surge in society's interest in human violence, relatively few studies have been conducted examining the closely related phenomenon of animal cruelty. Although several researchers have begun to identify some of the correlates of animal cruelty, few have attempted to understand how differences in the backgrounds of rural and urban residents have led to their abuse of animals. Using survey data from 261 inmates, the authors investigate how demographic, familial differences and species type have contributed to the frequency of acts of animal cruelty. In general, early exposure to animal abuse is a strong predictor of the subsequent behavior. However, rural inmates learned to be cruel by watching family members exclusively, whereas urban inmates learned from family members and friends. Moreover, urban inmates chose dogs, cats, and wild animals as their target animals; however, rural inmates chose only cats.  相似文献   
56.
Since its inception, green criminology has highlighted, examined and analysed environmental degradation and destruction. The ‘theft of nature’ is both an example and a driver of illegal and ‘lawful but awful’ acts and omissions that degrade the environment. Even though this theft is widespread and sometimes well known, it persists because powerful actors put forward an influential narrative of denial that obstructs interventions. This paper explores the role of denial in two thefts of nature—biopiracy and climate change—and compares and contrasts the manifestations of denial that contribute to their continuation. We consider the ‘appeal to higher loyalties’ (economic interests over environmental concerns), and discuss the implications if such denial goes unchallenged and remains the central narrative.  相似文献   
57.
The Federal Violent Crime Control and Law Enforcement Act of 1994 bans a group of military-style semiautomatic firearms (i.e., assault weapons) and ammunition magazines capable of holding more than 10 rounds. Ban advocates argue that these weapons are particularly dangerous because they facilitate the rapid firing of high numbers of shots. Though the banned guns and magazines were used in only a modest fraction of gun crimes before the law, it was hypothesized that a decrease in their use might reduce gunshot victimizations, particularly those involving multiple wounds and/or victims. In response to a Congressional mandate for an impact assessment of the law, this study utilized national and local data sources and a variety of analytical techniques to examine the ban's short-term impact on gun violence. The ban may have contributed to a reduction in gun homicides, but a statistical power analysis of our model indicated that any likely impact from the ban will be very difficult to detect statistically for several more years. We found no evidence of reductions in multiple-victim gun homicides or multiple-gunshot wound victimizations. The findings should be treated cautiously due to the methodological difficulties of making a short-term assessment of the ban and because the ban's long-term effects could differ from the short-term impacts revealed by this study.  相似文献   
58.
This essay investigates the first century of English colonization of the North American mainland, concentrating on the charters and letters patent that proponents of western planning secured over the course of the century. The elaborated legalities of chartering should be understood as a technology of planning and design. Charters allowed projectors both to justify their pursuit of particular territorial claims and to establish, with some precision, the conceptions of the appropriate, familiar, desired order of things and people that would be imposed onto uncharted social and physical circumstance.
The structures of authoritative sociolegal order planned by projectors encountered others implicit in the migrations of actual settlers. Investigating settlers'disagreement with and departure from projectors'designs, the essay discards common explanations—that these were inevitable corrections brought about by the intrusion of local environmental realities on English projectors'fantasies, or the realization of an implicit evolutionary logic of political development, or of legal reception. It argues that disagreements were more often the result of a collision of distinct English legal cultures brought, by migration, into an unavoidable proximity.
The essay counterposes the paradigm of "colonization" to both "common law reception" and "bottom-up localism" analyses of the formation of early American legal culture. It proposes that "colonization" also resolves the discontinuity between early (colonial) and later (U.S.) American history.  相似文献   
59.
Race/ethnicity, citizenship status, and trauma, have significant impact on delinquency and crime outcomes; though the reasons for some expected and unexpected crime pathways are still unanswered. Using data from the National Longitudinal Survey of Youth 1997 (n?=?7,103), this study found the following results: no difference in the likelihood of engagement in delinquency and crime between blacks and whites; cumulative trauma increased delinquency and crime rates for all racial and ethnic groups; racial and ethnic minority groups compared to whites reported a significantly higher level of childhood trauma experiences; and native-born female immigrant groups (but not male) were more likely to engage in delinquency and crime than first-generation female immigrant groups. Implications and recommendations are set forth.  相似文献   
60.
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