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941.
Abstract

The effectiveness of a stress management intervention designed to reduce affective distress in 79 student nurses who previously reported significant distress, was evaluated by comparing stress management with wait-list control. The intervention had reliable, positive effects on affective outcomes including General Health Questionnaire-30, State and Trait Anxiety Inventory, Beck Depression Inventory, and a measure of domestic satisfaction. The intervention also led to an increase in Direct Coping use.

State Anxiety immediately preceding two important examinations, i.e. at 3 and 18 month follow-up, was lower for students receiving stress management. However, no effect was detected on sickness, absence and examination performance following this intervention. Stress management delivered in groups reduces affective distress and increases adaptive coping use in both clinical and academic settings.  相似文献   
942.
Coping style and social support may represent mechanisms to explain the relationship between Type D personality and ill-health. This study investigated whether Type D is associated with physical symptoms and perceived stress in a non-cardiac population, and if these relationships are mediated by coping and social support. In a cross-sectional study, 304 participants (110 males, mean age 22.1 years) completed measures of Type D, physical symptoms, coping, perceived stress and social support. Results showed that Type D, the interaction of negative affectivity and social inhibition (NA?×?SI), was positively correlated with physical symptoms, perceived stress, and avoidant coping, and negatively correlated with social support, problem-focused coping and emotion-focused coping. A series of bootstrapped multiple mediator tests showed that social support and avoidant coping fully mediated the relationship between Type D and physical symptoms. Furthermore, social support and emotion-focused coping partially mediated the relationship between Type D and perceived stress. These findings demonstrate for the first time that Type D personality is associated with physical symptoms in a non-cardiac population. Social support and coping style represent mechanisms that can, in part, explain the relationship between Type D and physical symptoms, and Type D and perceived stress.  相似文献   
943.
Since 2001 there has been a significant increase in the use of intelligence, surveillance, and reconnaissance (ISR) analysis for tactical, operational, and strategic decision makers engaged in global operations. To meet this demand, US Air Force intelligence personnel participate in remote combat and graphic media exploitation operations (e.g., review of still imagery, video, and audio), the long-term psychological effects of which are not well understood. Research to date has focused primarily on outcomes related to how intelligence personnel work, versus the specifics of what they do. Military psychologists embedded in ISR units conducted studies to address this gap. Intelligence analysts participated in focus groups and surveys assessing the frequency of exposure, previous exposures to other potentially traumatic events, symptoms of PTSD, moral injury, and other psychosocial experiences. Results showed that exposure levels, albeit virtual, rivaled or exceeded those reported by a sample of special operations forces. Results also showed that specific types of exposures (e.g., witnessing US military casualties, civilian casualties, atrocities committed by the enemy) are related to increased posttraumatic stress and other sequelae that may not adequately be captured by standard posttraumatic stress disorder screening measures. The results contribute to the existing literature on posttraumatic stress, shed new light on the emerging construct of moral injury, and highlight challenges presented by remote combat and graphic media exploitation operations to force health sustainment and performance optimization. The authors provide directions for future research and recommendations for ongoing assessment, monitoring, and selection and training of ISR personnel.  相似文献   
944.
This meta-analysis compares the findings of empirical studies that employ either a traditional form of cognitive–behavioral-based exposure therapy or virtual reality exposure therapy (VRET) for the treatment of posttraumatic stress disorder (PTSD) to determine which is more viable and effective. Statistical analyses were performed on 26 studies to determine pre- to posttreatment effect sizes and interactions. Results demonstrated a trend toward significance in favor of traditional exposure therapy showing lower posttreatment PTSD. Limitations included a restricted number of relevant studies; future research on VRET for PTSD should orient more to experimental designs, larger samples, and increased use of control groups.  相似文献   
945.
This research studied the association between dimensions of operational stress, forms of risk-taking with small arms, and possible mediators. Operational threat and negative affect were predictors, unauthorized preparedness and risky games were dependent variables, and safety climate and personality profile from the Eysenck Personality Questionnaire—Revised Short Form were mediators. The participants were 461 compulsory service soldiers in 31 companies. The results revealed that operational threat is related to unauthorized preparedness, and positive–negative affect is related to risky games. Safety climate mediated risky games only. Unauthorized preparedness and risky games were influenced by the interaction of Psychoticism and the Lie scale from the Eysenck Personality Questionnaire—Revised Short Form.  相似文献   
946.
Despite efforts to understand the antecedents, correlates, and consequences of posttraumatic growth (PTG), the role of time since a traumatic event (time since event) vis-à-vis PTG is not well understood. Part of a larger project exploring experiences following emotionally distressing events among military veterans (N = 197) using Amazon’s Mechanical Turk (Mturk), in the current study, we sought to clarify associations between the time since event and PTG. We used cluster-analytic techniques and analyses of variance to (a) determine the number of clusters, and (b) assess differences in core constructs of PTG and participant characteristics across clusters. Results revealed 4 significantly different groups (i.e., clusters) characterized by differential associations between PTG and time since event. These groups also differed significantly in challenge to core beliefs, level of PTSD symptoms, intrusive and deliberate rumination, and age. The immediate moderate-growth group (Cluster 1) experienced moderate levels of PTG over shorter periods of time, severe PTSD symptoms, and was significantly younger. The low-growth group (Cluster 2) was characterized by minimal PTG, regardless of time, the least challenge to core beliefs, and low amounts of intrusive and deliberate rumination. The long-term small-growth group (Cluster 3) was primarily characterized by small amounts of PTG over longer periods of time. The high-growth group (Cluster 4) was characterized by high PTG, regardless of time, greater challenge to core beliefs, the highest amount of deliberate rumination, and the highest number of PTSD symptoms. Findings underscore heterogeneity within military veterans’ experiences of PTG over time.  相似文献   
947.
Absence epilepsy (AE) has been associated with lower than average cognitive functioning, which are clinically relevant in some and may predispose to problems later in life. This study aimed to assess cognitive development during long-term follow-up in children with AE. Thirty-one children with AE, who had undergone two neuropsychological assessments between 2010 and 2017 were analyzed retrospectively. Cognitive measurements were 1.7 ± 0.95 years apart. The difference in neurocognitive test scores was assessed on a group level and on an individual level using reliable change methodology. Results show that sustained attention was lower at the first measurement compared to the normative mean. Sustained attention improved during follow-up and 7 out of 14 children showed improvement after correction for practice effects. Receptive vocabulary showed a decline over time, but did not differ from the normative mean. Significant lower mean group scores were present for performance IQ, perceptual organization, processing speed, simple reaction times, and visual motor integration, while being stable over time in the majority of children. Cognitive development was not associated with seizure freedom. Mild-to-severe academic underachievement was present in 65% and comorbidities that might affect learning in 38%. This study in children with AE showed improvement in sustained attention during long-term follow-up while other cognitive weaknesses persisted over time, regardless of seizure freedom.  相似文献   
948.

The electronic properties of an Al = 9 tilt grain boundary with segregated Na and Ca impurity atoms have been calculated by a first-principles pseudopotential method. The results show that the boundary expands and the charge density decreases significantly over the whole boundary by the segregation of Na and Ca, and there are no stronger bonds than those associated with metallic bonding in the boundary even with the impurities. It is concluded that the embrittlement promotion mechanism by Na or Ca segregation in the Al boundaries is one kind of 'decohesion model'.  相似文献   
949.
Polymer molecules of polyvinyl alcohol (PVA) serve as a good Ag+?→?Ag0 reducer as well as a template to produce Ag0 nanocrystals of anisotropic shapes. Thin Ag–PVA films (50–100?µm thick) were prepared by carrying out the reaction in aqueous PVA (under heating conditions) and then spin casting the sample in this shape. A topotactic Ag+?→?Ag0 reaction and in-situ Ag0 growth occur in support over the PVA molecules (as per the local structure and Ag0–PVA interactions) of elongated surfaces. The Ag0 state is confirmed with 3d 5/2 and 3d 3/2 XPS signals of 368.37 and 374.13?eV binding energies, respectively. As analyzed with X-ray diffraction, it is a new allotrope with an orthorhombic structure, lattice parameters a?=?0.8535, b?=?0.8410?nm and c?=?0.4119?nm, and density ρ?=?9.69?g?cm?3. On heating in air, the well-known cubic structure develops, a?=?0.4082?nm (ρ?=?10.53?g?cm?3) after 150°C, whereas a?=?0.4071?nm (ρ?= 10.61?g?cm?3) after 300°C for 2?h. According to proposed models, it is a vacancy-stabilized allotrope, which evolves from multiply twinned particles.  相似文献   
950.

The relaxation of a space charge due to trapped electrons in an n + -i-n + hydrogenated amorphous silicon structure has been modelled by Solomon. Here we extend the model by obtaining analytical expressions for the current at the beginning of the relaxation as well as for long times when retrapping of electrons is taken into account. Our expression for the current at long times differs considerably from that given previously. Consequences for the derived values of the capture cross-sections of the gap states near the Fermi level are examined and discussed.  相似文献   
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