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111.
Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.  相似文献   
112.
Clinicians tend to overestimate their ability to recognize feigning behavior in psychiatric patients, especially if it concerns patients who have been admitted for observation. Feigning can be either externally motivated (e.g., for financial compensation, known as malingering) or internally motivated (e.g., to assume the “sick role,” known as factitious disorder). Persistent presentation of severe symptoms is usually associated with the factitious disorder. We present two patients with strong external incentives who consistently and convincingly feigned severe psychiatric symptoms during a protracted period of inpatient observation in a specialized center; both were engaged in a procedure for medical asylum. The first case presented with the clinical picture of a psychotic depression with severe motor symptoms, and the second case showed symptoms of a chronic post-traumatic stress disorder with secondary psychotic symptoms. Both cases were thoroughly investigated but feigning was overlooked, and unnecessary and harmful treatment interventions were given. To prevent iatrogenic damage, we recommend a critical attitude that takes malingering as an option into account in settings where patients are often involved in high stake legal procedures. A clinical sign that might indicate feigning is therapy-resistant symptoms. To rule out feigning a comprehensive, multimethod approach is required, but an active stance toward collateral information is essential. Specialized psychological tests may be useful for preliminary screening, but for their use in culturally diverse populations as in refugee mental health more research is needed.  相似文献   
113.
Hacking trauma is prevalent in forensic cases involving genocide and dismemberment, but research into the identification of this type of trauma is lacking. The present study examines characteristics of hacking and blunt force skeletal trauma in order to determine if there is a point at which blunt force trauma becomes distinguishable from hacking trauma. Ten implements with a range of blade angles (i.e., the striking surface of the implement) were used in conjunction with a controlled-force hacking device to impact 100 limb bones of white-tailed deer (Odocoileus virginianus). Observations of the trauma included the occurrence and degree of fragmentation, the entrance widths of the impacts, and composite scores of six hacking characteristics, especially the distinctive V-shaped kerf. ANOVA tests and regression analyses were used to assess the relationships between these characteristics and the blade angles. A significant relationship (p-value = 0.011) was found between the composite hacking scores and the blade angles, indicating that blunt force and hacking trauma can be distinguished. The entrance widths of the impacts exhibited a significant relationship with the blade angles (p-value = 0.037). There was also a significant relationship between the visibility of a V-shaped kerf in the bones (p-value = 0.003), with visibility decreasing around the 60° blade angle. These data should assist in establishing guidelines to differentiate hacking and blunt force skeletal trauma in cases where the implement is on a spectrum between sharp and blunt.  相似文献   
114.
What politicians devote attention to, is an important question as political attention is a precondition of policy change. We use an experimental design to study politicians’ attention to incoming information and deploy it among large samples of elected politicians in three countries: Belgium, Canada, and Israel. Our sample includes party leaders, ministers and regular members of parliament. These elites were confronted with short bits of summary information framed in various ways and were then asked how likely it was that they would read the full information. We test for three frames: conflict, political conflict, and responsibility. We find that framing moderates the effect of messages on politicians’ attention to information. Politicians react more strongly (i.e., they devote more attention) to political conflict frames than to non-political conflict frames and they react stronger to political responsibility attributions than to non-political responsibility attributions. Conflict frames attract more attention than consensus frames only from members of opposition parties. Political conflict frames attract more attention from government party politicians. These effects occur largely across issues and across the three countries.  相似文献   
115.
This study analyzes the short‐term impact of an exogenous, positive income shock on caregivers’ subjective well‐being (SWB) in Malawi using panel data from 3,365 households targeted to receive Malawi's Social Cash Transfer Program that provides unconditional cash to ultra‐poor, labor‐constrained households. The study consists of a cluster‐randomized, longitudinal design. After the baseline survey, half of these village clusters were randomly selected to receive the transfer and a follow‐up was conducted 17 months later. We find that the short‐term impact of household income increases from the cash transfer leads to substantial SWB gains among caregivers. After a year's worth of transfers, caregivers in beneficiary households have higher life satisfaction and are more likely to believe in a better future. We examine whether program impacts on consumption, food security, resilience, and hopefulness could explain the increase in SWB but do not find that any of these mechanisms individually mediate our results.  相似文献   
116.
117.
When a policy sector is confronted with a relatively strong and steep decline in legitimacy, we speak of an institutional crisis. We know little about the causes or consequences of these crises. This article explores how institutional crises are managed. It focuses on the effects of management strategies observed in a case study of an institutional crisis in the Netherlands. While we found that policy elites displayed a tendency to maintain the status quo of a policy sector, we also found that the effectiveness of their response strategies was negated by the counter‐response it evoked among freshly energized interest, advocacy and citizen groups. We conclude that the resolution of an institutional crisis is inherently contested. Based on our case study, we develop a theoretical model and formulate propositions that may help to improve our understanding of institutional crisis management.  相似文献   
118.
Families using the Housing Choice Voucher Program rarely experience large gains in neighborhood or school quality when compared with unassisted poor renters. Research on housing mobility programs has reached mixed conclusions about whether vouchers can improve neighborhood and school quality, especially in the long term. We revisit these findings using new data from the partial remedy to the Thompson v. HUD desegregation case in Baltimore, known as the Baltimore Housing Mobility Program (BHMP). Through targeted vouchers, intensive counseling and innovative policy features, the BHMP helped families move to low-poverty, nonsegregated neighborhoods with higher performing school districts. We examine residential outcomes for the first 1,800 families that moved through the program for a period of up to 9 years. We find that BHMP families moved to more integrated and affluent neighborhoods, in school districts with more qualified teachers and fewer poor students—and most families stayed in these neighborhoods beyond their initial lease-up period. Eventually, a small proportion of families moved to neighborhoods that are less white, but still significantly less poor and less segregated than their original communities. We interpret these findings in light of past mobility programs and discuss policy implications for the Housing Choice Voucher Program.  相似文献   
119.
This work examines how the American role in the Vietnam War has been portrayed in standard college- and university-level textbooks dealing with American foreign policy. It argues that this topic has been presented in a manner that leaves an incomplete understanding. This conclusion is based on scholarship that has been available for decades as well as much Cold War historiography that has appeared since 1975. I conclude that the distortions need to be addressed for several reasons. Their propagation produces bad scholarship, gratuitously alienates Americans from their institutions of government, and justifies anti-Americanism and authoritarianism elsewhere.  相似文献   
120.
While the effects of simulation-based courses on the knowledge of participating students may be marginal in relation to standard lecture and discussion-based courses, this article argues that the greatest leverage is gained by increasing participating students’ level of interest in the subject of study and in politics more broadly. Participants tend to become increasingly absorbed in their roles and in the politics of the institutions at the center of the simulation. To better consider this possibility, we conducted a survey of students participating in the 2015 Mid-Atlantic European Union Simulation and of appropriate control populations. The survey results indeed suggest that, much more than simply acquiring knowledge about the EU, the simulation experience serves to generate more robust interest in the subject of study.  相似文献   
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