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971.
Objective: Depressive symptoms are highly prevalent in heart failure (HF) patients, however the underlying etiology of depression in HF patients remains yet unclear. Hence, the goal is to examine the relative importance of inflammation, disease severity and personality as predictors of depression in HF patients. Design: Depressive symptoms (Hospital Anxiety and Depression Scale, depression subscale) were assessed at baseline and one-year follow-up in 268 HF patients (75.6% men; mean age?=?66.7?±?8.7). Markers of inflammation (TNFα, sTNFr1, sTNFr2, IL-6 and IL-10), disease severity (e.g. New York Heart Association (NYHA) classification) and personality (Type D personality, loneliness) were assessed at baseline. Results: At baseline, NYHA class, body mass index, educational level, Type D personality and loneliness were significantly associated with depression. Higher NYHA class (B?=?2.25; SE?=?.83), higher educational level (B?=?1.41; SE?=?.48), Type D personality (B?=?2.56; SE?=?.60) and loneliness (B?=?.19; SE?=?.05) were also independently associated with higher depression levels at one-year follow-up (all p-values?<?.005). Inflammation, brain natriuretic peptide and left ventricular ejection fraction were not related to depression over time. Conclusions: Personality factors, but not inflammation, were independent concomitants of depressive symptoms in patients with HF. Gaining more insight into the etiology of depression in HF patients is important in order to identify potential targets for novel interventions.  相似文献   
972.
973.
Abstract

The main objective of this study is to test the effects over time of three role stress variables (role conflict, role ambiguity and role overload) on the three burnout dimensions (emotional exhaustion, depersonalization and personal accomplishment). Based on theoretical models on burnout and on meta-analytical research, it is hypothesized that the three role stress variables will predict changes over time in emotional exhaustion and depersonalization, but not in personal accomplishment. The results obtained by means of hierarchical regression analysis partially support the hypothesis. The three role stress variables predict emotional exhaustion over time. Role conflict and role overload predict depersonalization over time. Finally, contrary to expectations, role ambiguity predicts personal accomplishment over time.  相似文献   
974.
The article introduces the situation of family therapy and systemic practice in the Czech Republic. It gives an overview of family therapy history and development in the country. Both historical and political background including major transformation events in the last couple of decades are presented so as to explain the contextual frame for major challenges, which Czech family and systemic therapists have been facing in this part of Europe. The current situation of family therapy in the Czech Republic is described in detail with regard to leading figures, major schools, training issues, international exchange and clinical practice in various settings.  相似文献   
975.
Antecedents to trust (propensity to trust, perceived trustworthiness) and trust behaviors were examined in relation to team performance in a complex eight-mission military peacekeeping simulation. Teams were colocated or distributed and stayed in the same or transferred to a different context at task transfer. In Experiment 1, an ability and competence factor accounted for most of the variance in perceived trustworthiness and greater perceptions of teammates' abilities/competences predicted posttransfer performance. One's perception of how others perceived one's ability/competence increased over missions. In Experiment 2, propensity to trust did not predict performance; however, trust in others' and one's own ability/competence and trust behaviors predicted performance. At task and/or context transfer, teams produced more monitoring and less cooperating language in their communication.  相似文献   
976.
Background: Children with acquired brain injury (ABI) present with high rates of psychological disorders commonly accompanied by deficits in hot and cold executive functions (EFs). Impairments in EFs have been reported to precede mental health problems. Moreover, children who are vulnerable to developing mental health problems in adulthood frequently present with a dysregulation profile in childhood, characterized by impairments in cognitive, behavioral and emotional regulation. Objective: To identify profiles of behaviors associated with impairment in hot and cold EFs and compare injury factors, environmental stressors and dysregulation profile between them. Methods: A latent profile analysis was conducted with 77 children with ABI aged between 6 and 12. Injury factors, child IQ, environmental stressors and the dysregulation profile were compared between these behavioral profiles. Logistic regressions were conducted to predict profile membership. Results: Two profiles were identified: Profile M, with mild deficits (1–2 SD above the mean) in working memory and social skills, and profile C, presenting clinically significant deficits (2–3 SD above the mean) in shift, initiate, working memory, planning and social skills and mild deficits in inhibit, emotional control and task monitor. Proximal environmental stressors (dysfunctional parenting practices, parental stress, parent’s executive dysfunction, anxiety-trait, and depressive symptoms) and dysregulation symptoms predicted profile membership, whereas injury factors, child IQ and distal environmental stressors did not. Conclusion: Following ABI, children with profile C are at risk of mental health problems and present with more proximal stressors. The dysregulation profile may be useful as a proxy for risk for later mental health problems in children with ABI.  相似文献   
977.
We model conducting pentagon chains with a multi-orbital Hubbard model and prove that well below half filling, exact ferromagnetic ground states appear. The rigorous method we use is based on the transformation of original hamiltonian into positive semidefinite form. This technique is independent of the spatial dimension and does not require integrability of the model. The obtained ferromagnetism is connected to dispersionless bands but in a much broader sense than flat-band ferromagnetism requires, where on every site a Hubbard term is present. In our case, only a small percentage of, even randomly distributed, sites are only interacting.  相似文献   
978.
979.

An effective Hamiltonian for the two-band Hubbard model was derived by a canonical transformation which was calculated and summed up to infinite order . The transformed Hamiltonian contains terms with strongly renormalized interaction energies. These new interaction energies show sign reversals as a function of the hopping integral in addition to a strong reduction in the charge-transfer gap and a significant increase in the attractive oxygen Hubbard term.  相似文献   
980.

A new approach to the surface photovoltage method is demonstrated on thick undoped microcrystalline silicon films grown on different substrates. The model, which includes top as well as bottom space-charge regions, gives a good picture of rather complex experiments and allows good fitting of theoretical curves to experimental results. This method gives us not only the diffusion length of minority carriers but also information on the existence and properties of the space-charge regions in the sample and the results are verified by comparison with the standard procedure.  相似文献   
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