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81.
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method.  相似文献   
82.
African indigenous vegetables (AIVs) have potential to sustainably address malnutrition, a growing problem in sub-Saharan Africa. Their consumption is however, limited by poor perceptions and lack of awareness of nutritional benefits. There is limited evidence of the effectiveness of community-focused information dissemination approaches in influencing participants’ perceptions and uptake of innovations in AIVs to address malnutrition. This article aims to fill this knowledge gap, using a case study focusing on pastoral communities in Monduli district in northern Tanzania. Target communities participated in a community-based nutritional outreach facilitated by the Good Seed Initiative (GSI), held at Monduli district hospital in September 2014. The results provide evidence of the achievements of the GSI intervention, and the effectiveness of alternative information dissemination approaches.  相似文献   
83.
This paper investigates to what extent socioeconomic status (SES)‐based affirmative action in college admissions can produce racial diversity. Using simulation models, we investigate the racial and socioeconomic distribution of students among colleges under the use of race‐ or SES‐based affirmative action policies, or targeted, race‐based recruitment policies. We find, first, that neither SES‐based affirmative action nor race‐targeted recruiting on their own produce levels of racial diversity achieved by race‐based affirmative action. However, the two policies in combination, although likely expensive, may yield racial diversity comparable to race‐based affirmative action. Second, the use of affirmative action policies by some colleges reduces the diversity of similar‐quality colleges without such policies. Third, the combination of SES‐based affirmative action and race recruiting results in fewer academically‐overmatched Black and Hispanic students than under race‐based affirmative action, but the schools that use both also see a reduction in the academic achievement of enrolled students.  相似文献   
84.
While the fertility effects of improving teenagers’ access to contraception are theoretically ambiguous, most empirical work has shown that access decreases teen fertility. In this paper, we consider the fertility effects of access to condoms—a method of contraception not considered in prior work. We exploit variation across counties and across time in teenagers’ exposure to condom distribution programs in schools. We find that access to condoms in schools increases teen fertility by about 12 percent. The results suggest that the effects of condom access varied significantly across different programs; the positive fertility estimates are driven by communities where condoms are provided without mandated counseling. Programs that mandated counseling have zero or negative fertility effects, but estimates on these counties are less robust across specifications.  相似文献   
85.
Abstract

Scalability can be understood as the ability to expand without changing. Yet, expanding an intervention to a global scale, we suggest, is a significant and difficult accomplishment. In this paper we propose to explore the kind of evidential exigencies that this accomplishment involves. To do so, we focus on the field of global health and examine how child immunization against the pneumococcus bacterium has been scaled up in low-income countries. The paper first attends to initial epidemiological scrutiny that revealed the existence of a large-scale public health problem and the possibility of an expandable solution (vaccination). It then describes the set-up of a funding arrangement using overseas aid to purchase vaccine doses manufactured by pharmaceutical companies, before paying attention to various frictions that affect the widespread use of pneumococcal vaccines. In these different moments through which scalability is accomplished, always partially and temporarily, we show that a dual activity can be witnessed, a pivoting between referential work and forward projection. To conclude, we suggest that scalability is more usefully approached as a form of expansion that is always attentive to the possibilities of change.  相似文献   
86.
This paper deals with the long-term evolution of dock labor in Dakar. Through the utilization of archival sources and their analysis, this investigation explores the changes that occurred in this sector and primarily the reform plan developed during the world wars but that was never introduced into the labor regulations, mainly due to the colonial regime. In addition, this paper studies the legal changes since the 1970s when the dockers’ statute was settled. Furthermore, this research uses oral testimony from retired Senegalese dockers to study the way these workers observed these structural changes. It is the first time that this topic has been explored for the port of Dakar from a historical long-term perspective.  相似文献   
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88.
We introduce experimental research design to the study of policy diffusion in order to better understand how political ideology affects policymakers’ willingness to learn from one another's experiences. Our two experiments–embedded in national surveys of U.S. municipal officials–expose local policymakers to vignettes describing the zoning and home foreclosure policies of other cities, offering opportunities to learn more. We find that: (1) policymakers who are ideologically predisposed against the described policy are relatively unwilling to learn from others, but (2) such ideological biases can be overcome with an emphasis on the policy's success or on its adoption by co‐partisans in other communities. We also find a similar partisan‐based bias among traditional ideological supporters, who are less willing to learn from those in the opposing party. The experimental approach offered here provides numerous new opportunities for scholars of policy diffusion.  相似文献   
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