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1.
The authors hypothesize that depressed states evolved to minimize risk in social interactions in which individuals perceive that the ratio of their social value to others, and their social burden on others, is at a critically low level. When this ratio reaches a point where social value and social burden are approaching equivalence, the individual is in danger of exclusion from social contexts that, over the course of evolution, have been critical to fitness. Many features of depressed states can be understood in relation to mechanisms that reduce social risk in such circumstances, including (a) hyper-sensitivity to signals of social threat from others, (b) sending signals to others that reduce social risks, and (c) inhibiting risk-seeking (e.g., confident, acquisitive) behaviors. These features are discussed in terms of psychosocial and neurobiological research on depressive phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
The present study examined whether siblings experience marital conflict differently and whether such differences, if present, were associated with differences in their adjustment. Self-report data about marital conflict, children's depressed mood, behavioral conduct, and externalizing problems were obtained from 122 sibling pairs (mean ages = 10 and 12 years) and their parents. Results indicated that siblings were significantly different in exposure to and appraisals of marital conflict. Differences in siblings' exposure to marital conflict were significantly correlated with differences in their depressed mood, behavioral conduct, and externalizing problems. Differences in siblings' feelings of self-blame for marital conflict were significantly correlated with differences in their depressed mood and behavioral conduct. Children who experienced more marital conflict than their siblings had more adjustment problems than their siblings. These results highlight the importance of studying siblings' unique experiences of marital conflict to better understand its impact on children's adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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根据高速公路路面实际情况对路面板脱空现象进行压浆处理。路面板脱空位置是通过弯沉法和雷达观测法确定的,并结合路面唧泥情况钻孔法进行压浆,最终取得了较好的压浆效果。 相似文献
4.
运用数值模拟方法计算了颗粒在旋风分离器中的运动轨迹,得到了不同粒级的颗粒分离效率和分离器总压降,并将分离效率计算结果与Barth经验模型,压降计算结果与Dirgo经验模型计算值进行比较,发现运用CFD模拟计算与经验模型结果基本一致,分离效率略低、压降比较吻合。同时发现不同粒径颗粒逃逸的主要途径不完全相同,在入口上方或下部进入的离子逃逸概率较高。研究结果还表明,应用计算流体力学来研究旋风分离器的分离性能方便可行。 相似文献
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为了研究三肇凹陷扶杨油层油成藏规律,采用油分布与源岩、断裂空间叠合研究的方法,对扶杨油层油侧向运移模式及其对油成藏与分布的控制作用进行了研究。结果表明,上覆青一段源岩生成的油向下伏扶杨油层侧向运移的模式为:断裂错断使上覆青一段源岩与下伏扶杨油层中的不同油层组对接,青一段源岩生成的油在浮力作用下侧向运移进入扶杨油层的不同油层组中;断裂错断阶数越多,青一段源岩生成的油侧向运移进入扶杨油层中油层组的层位越深,反之则越浅。青一段源岩生成的油向扶杨油层侧向运移对其油成藏与分布的控制作用主要表现在2个方面:①断裂密集带两侧的地垒构造是扶杨油层油成藏的有利部位;②扶一油层组是青一段源岩生成的油向扶杨油层侧向运移的主要层位。这一研究成果对于指导三肇凹陷扶杨油层石油勘探具有推广价值。 相似文献
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Brendgen Mara; Lamarche Véronique; Wanner Brigitte; Vitaro Frank 《Canadian Metallurgical Quarterly》2010,46(2):491
The present study examined to what extent different types of friendship experiences (i.e., friendlessness, having depressed friends, and having nondepressed friends) are associated with early adolescents’ longitudinal trajectories of depressed mood. On the basis of a sample of 201 youths (108 girls, 93 boys), we identified 3 distinct longitudinal profiles of depressed mood from Grade 5 (age 11) through Grade 7 (age 13): one group with consistently low levels of depressed mood, another group showing a sharp increase in depressed mood from late childhood through early adolescence, and a 3rd group with consistently high levels of depressed mood from late childhood through early adolescence. Subsequent analyses revealed that, compared to friendless youths, youths with nondepressed friends showed less elevated trajectories of depressed mood, whereas youths with depressed friends showed more elevated trajectories. The theoretical and practical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Cognitive reactivity (CR) is a psychological vulnerability marker of depression, whereas response to acute tryptophan depletion (ATD; a serotonergic challenge procedure) is a biological vulnerability marker. The aim of this study was to investigate the relationship between these markers. Thirty-nine remitted depressed patients participated in 2 ATD sessions in a double-blind crossover design. CR, assessed prior to the ATD sessions, predicted depressive response to high-dose ATD. CR also diminished the effects of 2 known predictors of ATD response: gender and residual symptoms. Neuroticism and behavioral inhibition were unrelated to ATD response. CR is associated with an increased sensitivity to reductions of serotonin concentrations. These findings present a small step toward unifying cognitive and neurobiological theories of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
松辽盆地南部泉头组四段—姚家组西部坡折带的成因及演化 总被引:15,自引:2,他引:13
大型坳陷湖盆中存在与海相盆地中陆坡相似的坡折带。根据对地质、地球物理资料等的综合研究,松辽盆地南部的泉头组四段-姚家组发育两级西部坡折带(套堡-双岗高位坡折带和红岗-海坨子低位坡折带),同一坡折带在不同的发育时期有着不同的主控因素。早期两级坡折带都受到基底断裂的影响,后期发育过程中,套堡-双岗高位坡折带的主控因素是物源的方向和侵蚀力,红岗-海坨子低位坡折带后期发育主要受沉积物的供应和差异压实作用的影响。坡折带形成的主控因素不同,则坡折的规模、延伸性以及坡度均存在一定的差异。 相似文献