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591.
The use of terminal sedation to control theintense discomfort of dying patients appearsboth to be an established practice inpalliative care and to run counter to the moraland legal norm that forbids health careprofessionals from intentionally killingpatients. This raises the worry that therequirements of established palliative care areincompatible with moral and legal opposition toeuthanasia. This paper explains how thedoctrine of double effect can be relied on todistinguish terminal sedation from euthanasia. The doctrine of double effect is rooted inCatholic moral casuistry, but its applicationin law and morality need not depend on theparticular framework in which it was developed. The paper further explains how the moral weightof the distinction between intended harms andmerely foreseen harms in the doctrine of doubleeffect can be justified by appeal to alimitation on the human capacity to pursue good.  相似文献   
592.
The current study tests whether the presence of callous–unemotional (CU) traits designates a group of children with conduct problems who show an especially severe and chronic pattern of conduct problems and delinquency. Ninety-eight children who were selected from a large community screening of school children in grades 3, 4, 6 and 7 were followed across four yearly assessments. Children with conduct problems who also showed CU traits exhibited the highest rates of conduct problems, self-reported delinquency, and police contacts across the four years of the study. In fact, this group accounted for at least half of all of the police contacts reported in the sample across the last three waves of data collection. In contrast, children with conduct problems who did not show CU traits continued to show higher rates of conduct problems across the follow-up assessments compared to non-conduct problem children. However, they did not show higher rates of self-reported delinquency than non-conduct problem children. In fact, the second highest rate of self-reported delinquency in the sample was found for the group of children who were high on CU traits but without conduct problems at the start of the study.  相似文献   
593.
Although turnover intentions are the strongest predictors of voluntary turnover behaviours, many employees who express intentions to leave do not. To explain why some employees translate turnover intentions into behaviour and others do not, this study examines the moderating effect of temporal focus (i.e. the degree to which one thinks about the past, present and future) between turnover intentions and voluntary turnover, using the lens of theory of planned behaviour. Data were collected from 683 full-time employees in a range of organisations at three points in time. Results show that past temporal focus conditions the positive relationship between turnover intention and turnover, such that the relationship is stronger when past temporal focus is high. Future temporal focus has an opposite moderating effect, such that the relationship between turnover intention and turnover is weaker when future temporal focus is high. Results show no significant moderating effect of current temporal focus. Overall, temporal focus helps explain why some employees leave and others stay by conditioning the likelihood of translating turnover intentions into quitting. We speculate that a dominant, unspoken paradigm in turnover research is an assumption that individuals are current focused, yet our results suggest scholars should explicitly examine this assumption.  相似文献   
594.
This study investigated the associations among exposure to violence, emotional stability, and psychological symptoms. The moderating role of emotional stability in the relationship between exposure to violence and anxiety and depression was examined in a sample of 482 high school students in Hong Kong. Results showed that both witnessing violence and low levels of emotional stability were positively associated with symptoms of anxiety and depression. Low levels of emotional stability exacerbated the relation between witnessing violence and symptoms of anxiety and depression; the opposite pattern was found among adolescents with high levels of emotional stability. This study sheds light on the role of emotional stability in ameliorating the detrimental effects of witnessing violence on symptoms of anxiety and depression among adolescents. Findings of this study also have implications for the development of emotionally healthy personalities.  相似文献   
595.
The thermal stability and glass-forming ability (GFA) of Se80? x Te20Ag x (x?=?0,?3,?5,?7 and 9) chalcogenide glasses have been investigated using differential scanning calorimetry (DSC). The DSC runs have been taken at five different heating rates (10, 20, 30, 40 and 50?K/min) under non-isothermal condition. The thermal stability and GFA are monitored through determination of the temperature difference ΔT?=?T c???T g, where T c is the onset crystallization temperature, T g is the glass transition temperature, H l is the stability parameter, ΔH c is the enthalpy released during crystallization and F i is the fragility index. The activation energy of crystallization E c and crystallization rate factor K have also been determined as indicators of the thermal stability of the above-mentioned samples. It is found that Se71Te20Ag9 is the most stable among all the samples of the series.  相似文献   
596.
The influences of doping elements (Ti, Zr, Hf, V, Ta, Cr, Mo, W and Al) on the heats of formation of Nb, Nb5Si3 and Nb3Si have been studied using first-principles pseudopotential plane-wave method based on density functional theory. Site preferences of dopants in Nb5Si3 and Nb3Si intermetallics are first determined by comparing the heats of formation of the systems with different site occupations of the doping atoms. The partitionings of dopants between the equilibrium phases Nb and Nb5Si3 of Nb–Si in situ composites are then discussed and compared with experimental results. Phase partitioning behaviours of the alloying elements are found to depend strongly on the number of their valence electrons. By calculating the enthalpy of reaction regarding the eutectoid decomposition of Nb3Si phase, we conclude that Ta is a Nb3Si stabiliser while other dopants destabilise Nb3Si at the investigated concentration.  相似文献   
597.

BiSbTe3 single crystals have been grown by the Bridgman technique. Microscopic observations of the as-grown crystals reveal typical features, such as striations on the top free surface, which are attributed to the effect of growth conditions. A nitric-acid-based reagent capable of revealing dislocations has been developed and tested. Etch pits are produced at the dislocation sites, but some discrepancies have been observed on matched cleavage surfaces. The structural difference between the matched cleavage surfaces is discussed.  相似文献   
598.
Abstract

Experimental studies show that training people to attend to negative stimuli makes them more likely to respond with greater anxiety to stress. The present study investigated this effect in students using measures of cardiovascular responses to stress and examined whether individual differences influence the impact of attention training on stress responses. Using a standard dot probe task, 30 participants underwent negative attentional bias training and 34 participants underwent anti-negative training before completing a stressful speech task. Results indicated that, overall, participants exhibited acclimatization to the procedures (indicated by a dip in blood pressure post-training) and normal stress responding (indicated by elevated blood pressure in response to stress; p<.001). However, consideration of participants’ scores for neuroticism/emotional-stability revealed important differences in how the intervention impacted on cardiovascular profiles (p=.008). For participants with high neuroticism scores, the negative attentional bias intervention elicited more exaggerated stress responding than the anti-negative intervention. For those with low neuroticism scores (i.e., emotionally stable participants), the anti-negative intervention was associated with elevated post-intervention blood pressure and higher blood pressure reactivity to stress. These findings provide evidence of the impact of attentional bias manipulation on physiological stress reactivity and suggest the effect is highly contingent on individual temperaments.  相似文献   
599.
Bilateral transfer in a fast tapping task was investigated under normal (+FB) and reduced (-FB) feedback conditions, in the -FB experiment 36 Ss were assigned to 3 groups: preferred (PH) to non-preferred (NPH) shift; NPH to PH; and alternating trials of PH and NPH. With + FB 2 further groups of 12 Ss transferred PH to NPH or NPH to PH. 8 preshift and 8 postshift trials were given. The alternating group had 8 PH and 8 NPH trials. In preshift performance increment was found in ail groups except in +FB with NPH. With +FB some facilitation in transfer was obtained for the NPH; under -FB marked positive transfer was found for the PH. Alternating PH and NPH performance conformed to preshift levels. Results were discussed in terms of differential central control processes for the two hands.  相似文献   
600.
Changes to intersegmental locomotor control patterns may affect body stability. Our study aimed to (a) characterize upper body dynamic stability in response to the unilateral addition of mass to the lower extremity and (b) evaluate the efficacy of 2 different stability measures commonly used in the literature to detect resulting symmetrical step pattern modifications across the weighted segments (spatial) and between epochs of the gait cycle (temporal). Young adults walked on a treadmill while unloaded or with weights applied unilaterally to their foot, shank, or thigh. Both margin of stability and local dynamic stability (LDS) estimates detected similar trends of distal segment weighting resulting in more unstable upper body movement compared to proximal weighting; however only LDS detected anteroposterior changes in upper body stability over time.  相似文献   
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