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221.
When a bullet punctures a surface, it leaves behind a bullet impact, which can be analyzed in order to determine the origin and trajectory path from which a bullet was discharged using many different scientific methods to reconstruct a shooting scene. The purpose of the research was to test the accuracy and repeatability of reconstructing the impact angle of single bullet impacts using the ellipse method. The research was conducted by firing various calibers of ammunition into drywall panels positioned at varying angles of incidence from 88° until ricochet occurred. This was done in order to determine which caliber type and angle of incidence are most accurate and precise for reconstructing a shooting scene. The study examined four caliber types fired into drywall panels, with 5 repeated shots for each of the 11 angles of incidence (n = 220). Furthermore, 31 participants partook in the study to estimate a bullet impact angle of incidence utilizing the ellipse method. The results show that the best performance (accuracy and repeatability) is seen with the measurements of the 0.45 caliber ammunition. When angle of incidences is low (<64°), the performance (accuracy and repeatability) was seen to be better in all caliber ammunitions. Overall, the data provided for single bullet impacts deposited in drywall show that the ellipse method is useful in providing measurements for most crime scene reconstruction purposes and has also demonstrated that results vary depending on the type of ammunition, firearm, and angle of incidence being examined.  相似文献   
222.
X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm2). Hence, a fingermark pattern contaminated with caffeine, TiO2, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence.  相似文献   
223.
Recent increases in deaths in the United States from synthetic opioids such as fentanyl and fentanyl analogues (fentanyls) have raised concerns about possible occupational exposures to these potent agents. Medicolegal death investigators and autopsy suite staff might perform job tasks involving exposure to fentanyls. The potential for exposure to fentanyls among medicolegal death investigators and autopsy technicians at a state medical examiner's office was evaluated through review of caseload characteristics, injury and illness logs, and procedures and policies and discussions with management and employee representatives. The evaluation showed that this medical examiner's office had low potential for work-related exposure to fentanyls; its standard operating procedures and personal protective equipment requirements should reduce the potential for occupational exposure. Medicolegal death investigation agencies can develop and implement guidance to control exposures and provide workforce education and training to reduce the potential for work-related exposure to fentanyls.  相似文献   
224.
Children of immigrants who do translations and who interpret for others using their heritage language and English are known as language brokers. Although prior research suggests that children of immigrants’ perceptions of the language brokering experience vary greatly—from feeling a sense of efficacy to feeling a sense of burden—what remains unanswered in the literature is identification of the antecedents and processes that help to explain the varying psychological experience of language brokers. Using data from a two-wave prospective longitudinal study of 256 Chinese American adolescents, the present study tested potential mechanisms that may be responsible for adolescents’ perceptions of the language brokering experience as a sense or burden or sense of efficacy. The results demonstrate that adolescents’ Chinese orientation sets in motion a family process that is linked to variations in the perceptions of adolescents’ language brokering experience. Adolescents who are more Chinese oriented have a stronger sense of familial obligation, and these adolescents are more likely to perceive that they matter to their parents. Adolescents’ perceived sense of mattering to parents, in turn, is associated positively with a sense efficacy, and negatively with a sense of burden as language brokers. Those adolescents who are less Chinese oriented have a weaker sense of familial obligation, and these adolescents are more likely to feel a sense of alienation from their parents. Adolescents’ sense of perceived alienation from parents, in turn, is associated with a sense of burden as language brokers. Implications for developing interventions for children who act as language brokers for their parents are discussed.
Su Yeong Kim (Corresponding author)Email: Email:
  相似文献   
225.
Considerable research has focused on the reliability and validity of informant reports of family behavior, especially maternal reports of adolescent problem behavior. None of these studies, however, has based their orientation on a theoretical model of interpersonal perception. In this study we used the social relations model (SRM) to examine family members’ reports of each others’ externalizing and internalizing problem behavior. Two parents and two adolescents in 69 families rated each others’ behavior within a round-robin design. SRM analysis showed that within-family perceptions of externalizing and internalizing behaviors are consistently due to three sources of variance; perceiver, target, and family effects. A family/contextual effect on informant reports of problem behavior has not been previously reported.  相似文献   
226.
The Laboratory for Analytic Sciences (LAS) at North Carolina State University, funded by the National Security Agency, is a collaborative, long-term research enterprise focused on improving intelligence analysis using Big Data. In its work, LAS has recently begun dealing with the trade-off between the collection, storage, and use of large unclassified data-sets and analyst privacy. We discuss particular privacy challenges at LAS, analyze privacy principles in the life cycle of LAS unclassified data-sets, what intelligence analysts themselves think about these privacy concerns, and recommend possible best practices potentially applicable to LAS, as well as future Big Data laboratories and research centers that collaborate with intelligence communities.  相似文献   
227.
Abstract

The 2013–2016 West African Ebola outbreak was both a catastrophic public health disaster and a rare research opportunity. This paper analyses how the tensions between the humanitarian imperatives of disease control and the epistemic conventions of bioscientific inquiry played out in the accelerated development, testing and licensure of Ebola vaccines. Beginning with the epidemiological projections of the disease’s spread, the paper develops the notion of evidentiary charisma to capture the power of experimental designs and data packages to marshal public health salience, recruit moral legitimacy and short-circuit scientific contestation. Attention to the charismatic dimensions of Ebola vaccine R&D helps to unpick the simultaneous appeals to exception and convention in the unfolding of a global health crisis, and to trace the normative and technical contours of the emerging paradigm of emergency research.  相似文献   
228.
Abstract

What are the epistemological and political contours of evidence today? This introduction to the special issue lays out key shifts in the contemporary politics of knowledge and describes the collective contribution of the six papers as an articulation of what we describe as a ‘new empiricism’, exploring how earlier historical appeals to evidence to defend political power and decision-making both chime with and differ from those of the contemporary era. We outline some emerging empirical frontiers in the study of instruments of calculation, from the evolution of the randomized controlled trial (RCT) to the growing importance of big data, and explore how these methodological transformations intersect with the alleged crisis of expertise in the ‘post-truth’ era. In so doing, we suggest that the ambiguity of evidence can be a powerful tool in itself, and we relate this ambiguity to the ideological commitment and moral fervour that is elicited through appeals to, and the performance of, evaluation.  相似文献   
229.
Voluntary policy compliance is an important yet rarely studied topic in public administration. To address the paucity of research, this article proposes and empirically tests a conceptual framework that ties policy transparency and policy understanding to voluntary policy compliance intentions. The reasoning is that the extent to which citizens understand a policy contributes to their intentions to comply with that policy. Further, the authors argue that policy transparency indirectly influences voluntary policy compliance intentions through a positive effect on citizens’ levels of policy understanding. To enhance the validity of the findings, the authors assess these relationships across two policy domains. The findings reflect an indirect positive effect of transparency on voluntary compliance occurring through policy understanding. However, this emerged only for one policy domain. These results suggest that the effects of policy transparency on policy understanding and voluntary policy compliance intentions may depend on the policy domain.  相似文献   
230.
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