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31.
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   
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This article examines the patterns and changes in public perceptions of domestic income inequality in Hong Kong in the past two decades and explains individual variations in these perceptions. It found that the perceived seriousness of income disparities had been persistently high, while the perceived unjustness of income disparities showed a fluctuating trend. Our findings lent partial support to the structural position thesis that the privileged groups are less likely than the underprivileged groups to consider existing income disparities to be serious and unjust. Nonetheless, the popular understanding of poverty is still biased towards ‘individual’ explanations, and this perhaps explains why the government is less willing to tackle the economic and political foundations of poverty in Hong Kong.  相似文献   
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The activity of calcium pumping adenosine triphosphatase (Ca2+-ATPase) in cardiac sarcoplasmic reticulum plays a pivotal role in myocardiac contraction-relaxation. The Ca2+-ATPase activity is controlled by phosphorylation and dephosphorylation of a sarcoplasmic reticulum protein "phospholamban" in response to neurotransmitters and drugs. To clarify the role of Ca2+-ATPase in the development of cardiac rigor mortis, we examined the changes of cardiac rigidity and cardiac sarcoplasmic reticulum Ca2+-ATPase activity up to 5 h after the decapitation of rats. Fifteen minutes after decapitation, the rats showed a cardiac rigidity on left ventricles. After 30 min, rigidity was obvious over the whole heart. After 1 h, the rigidity reached a high degree which was maintained for the rest of the observation period. On the other hand, the Ca2+-ATPase activity controlled by phosphorylation and dephosphorylation of phospholamban did not change for the whole observation period (5 h). Another Ca2+-ATPase activity representing the total amount of Ca2+-ATPase in sarcoplasmic reticulum gradually decreased. The data suggest that no significant phosphorylation or dephosphorylation of phospholamban occurs for a short time, at least for 5 h, after death and that the Ca2+-ATPase tends to relax the myocardium against the development of cardiac rigor mortis.  相似文献   
36.
Hopelessness is implicated in multiple psychological disorders. Little is known, however, about the trajectory of hopelessness during adolescence or how emergent future orientation may influence its trajectory. Parallel process latent growth curve modelling tested whether (i) trajectories of future orientation and hopelessness and (ii) within-individual change in future orientation and hopelessness were related. The study was comprised of 472 adolescents [52% female, 47% Caucasian, 47% received free lunch] recruited at ages 12–13 who completed measures of future orientation and hopelessness at five annual assessments. The results indicate that a general decline in hopelessness across adolescence occurs quicker for those experiencing faster development of future orientation, when controlling for age, sex, low socio-economic status in addition to stressful life events in childhood and adolescence. Stressful childhood life events were associated with worse future orientation at baseline and negative life events experienced during adolescence were associated with both an increase in the trajectory of hopelessness as well as a decrease in the trajectory of future orientation. This study provides compelling evidence that the development of future orientation during adolescence is associated with a faster decline in hopelessness.  相似文献   
37.
Five years on from the Tunisian revolution, Tunisia stands as the sole success story of the Arab Spring. The country since then has managed to adopt a pluralist and democratic constitution, and held three free and fair elections. Accordingly, in the eyes of several observers, Tunisia is now in the process of consolidating its new democracy. However, the reality on the ground seems much gloomier, as most recent opinion surveys suggest that there is a significant degree of dissatisfaction, not only with political parties and Parliament but also with the very institution of democracy. Nevertheless, what accounts for this change? After the collapse of the long-lasting and oppressive Ben Ali regime, how, just in five years, has Tunisians’ confidence in the democratic process changed? This article accounts for this state of affairs from a party politics view, arguing that political parties, which are the main protagonists of the consolidation process, fail to fulfill their role of acquiring legitimacy for the new regime. While party–state relations seem to be stabilized due to the inclusiveness of the constitution-making process, both inter-party relationships and the relationship between parties and society suffer from numerous flaws which, in turn, hamper the democratic consolidation process.  相似文献   
38.
Although research consistently suggests that adolescents in single-mother families are at increased risk for depression, the mechanisms that explain this relationship are unclear. In a community sample of adolescents (N?=?368; ages 12–16; 50?% female; 50?% White) and their mothers (42?% single), adolescents completed measures of depressive symptoms, rumination, and depressogenic inferential style at baseline and two yearly follow-ups. Mothers reported on stressful events that occurred in the child’s life from birth until baseline. Adolescents raised by single mothers, relative to partnered mothers, experienced more childhood stressors and higher rumination levels at 1-year follow-up. Additionally, higher rumination mediated the relationship between single motherhood and greater youth depressive symptoms at the 2-year follow-up. Clinical implications and developmental considerations are discussed.  相似文献   
39.
The aim of this study is to define organizational citizenship levels of physicians working in public hospitals. The population of the study consists of the physicians employed in the hospitals run by the Ministry of Health in Istanbul. The Organizational Citizenship Level Scale was used for the collection of data. It was found that the participants’ organizational citizenship levels were the highest in the “conscience” subsection and the lowest in the “praising the organization” subsection. Findings of this study provide clear information for the decision-makers and hospital managers in developing working conditions of physicians in public hospitals.  相似文献   
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It is argued here that much of the literature on patron‐client relations is unsatisfactory because it tends to conceptualise the ruling classes of underdeveloped areas as individualised power brokers or ‘strong men’. Instead, one must identify those specific means of production which mark the class position of patrons, and which ultimately, are the basis of their power. Clientelism therefore not only refers to the economic position of the patrons, but also to a specific form of political power which is defined by the patron's relationship to the state. The paper addresses these questions by analysing the local ruling cliques of several communities in Central Sardinia. The pre‐World War II cliques differ markedly from those after the war, but they all have in common that they monopolise, at the local level, access to the state apparatus, that they are its local representatives, and that they are organised, and organise other classes, on the basis of kinship.  相似文献   
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