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Nusslock Robin; Abramson Lyn Y.; Harmon-Jones Eddie; Alloy Lauren B.; Hogan Michael E. 《Canadian Metallurgical Quarterly》2007,116(1):105
On the basis of the behavioral approach system (BAS) dysregulation theory of bipolar disorder, this study examined the relation between occurrence of a BAS activation-relevant life event--goal striving--and onset of hypomanic and depressive episodes and symptoms. In particular, the authors examined the relation between preparing for and completing final exams (a goal-striving event) and onset of bipolar spectrum episodes and symptoms in college students with bipolar II disorder or cyclothymia (i.e., "soft" bipolar spectrum conditions). One hundred fifty-nine individuals with either a bipolar spectrum disorder (n=68) or no major affective psychopathology (controls; n=91) were further classified on the basis of whether they were college students (i.e., completed final exams). Consistent with the BAS dysregulation theory, preparing for and completing final exams was associated with an increase in hypomanic but not depressive episodes and symptoms in individuals with a soft bipolar spectrum diagnosis. Furthermore, self-reported BAS sensitivity moderated the presence of certain hypomanic symptoms during final exams. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Walter Savassi Eddie Mancini 《The Structural Design of Tall and Special Buildings》2004,13(4):315-333
In a previous paper (Mancini and Savassi, 1999), it was shown that every plane panel, used to brace tall building structures, can be easily and generally approached through the use of the continuous medium technique (CMT) (Albigés and Goulet, 1960). In that paper, following a so‐called local formulation, i.e., by deriving the governing differential equations system of the panel, in terms of u(z) panel horizontal displacement and wi columns or walls axial displacements, the equivalence (likeness) of formal mathematics, and hence of structural behaviour, between the panel composed by a pair of shear walls associated by lintel beams and another panel formed by the plane association, by pinned horizontal bars, of one shear wall and one single bay frame, was also shown. In both cases, axial deformations due to axial forces on vertical members were taken into account. In this paper, confirming those conclusions, but now following a global formulation (i.e., considering the total potential energy of each panel: strain energy plus applied load potentials), the mathematical equivalence between those two types of plane panels is again revealed by comparison of their two total potential energy analytical expressions. Additionally, based on that variational approach, the one‐dimensional finite element formulation is presented. This enlarges the possibilities of solutions for more general types of panels, like those with variable geometry or loading, without any further difficulty. The procedure, for any type of panel, can be codified in one single computer program, very similar to those used to solve plain continuous beam problems. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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We have examined the applicability of this simple and effective test to polymer systems widely used in the medical industry. First, it was found that not every polymer examined exhibited a distinct onset of autocatalytic oxidation detectable by DSC. However, for cases where distinct onsets are found, powerful insights can be obtained. These included activation energy of the degradation, thermal oxidative shelf life prediction, and correlation, with product performances. Actual examples are presented to illustrate the utility of the test. 相似文献
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Research bearing on several popular conceptions of the major determinants of anger arousal indicates that the particular appraisals often identified as causes of anger frequently only serve to affect the intensity of the anger that is generated. Research into effects of physical pain or other physically unpleasant conditions or involving social stresses suggests that decidedly aversive conditions are a major spur to anger. Experiments are also reviewed showing that anger-related muscular movements can also lead to anger-related feelings, memories, cognitions, and autonomic responses. Alternative explanations for the findings are discussed. The authors urge emotion theorists to widen their methodology and analyses so that they give careful, detailed attention to the many different factors that can influence anger. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Eddie Cheng 《Information Sciences》2007,177(22):4877-4882
We prove that when linearly many vertices are deleted in a Cayley graph generated by a transposition tree, the resulting graph has a large connected component containing almost all remaining vertices. 相似文献
7.
We discuss the notion of \(H\) -centered surface area of a graph \(G\) , where \(H\) is a subgraph of \(G\) , i.e., the number of vertices in \(G\) at a certain distance from \(H\) , and focus on the special case when \(H\) is a length two path to derive an explicit formula for the length two path centered surface area of the general and scalable arrangement graph, following a generating function approach. 相似文献
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Transmission Control Protocol (TCP) provides mechanisms for reliable data communications. Although it works well in wired networks, it fails to offer satisfactory performance in lossy and wireless environments. And in the multi-hop wireless infrastructure, packet delivery suffers high cumulative loss rate if traveling over multiple wireless hops. The Selective acknowledgment (SACK) is one header option that might be used to combat segment corruptions in air channels. In this paper, an alternative set of flow control mechanisms is proposed to handle high packet loss rate in a wireless medium. Using a measurement-based mechanism, sustainable segment delivery is achievable through a novel size-reduction method. Multiple segment retransmission mechanisms are introduced to reduce successive timeout events. One single byte loss is sufficient to waste all other bytes in a file received at a destination. That is, a good TCP flow control mechanism should provide a high successful file transmission completion rate, and this is set as our design goal. Through thorough simulations, our proposed multi-segment retransmission designs perform with higher successful file transfer rate and fewer timeout events than NewReno and SACK under a wide range of packet loss probabilities. 相似文献
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We present an explicit formula for the surface area of the (n,k)-star graph, i.e., the number of nodes at a certain distance from the identity node in the graph, by identifying the unique cycle structures associated with the nodes in the graph, deriving a distance expression in terms of such structures between the identity node of the graph and any other node, and enumerating those cycle structures satisfying the distance restriction.The above surface area derivation process can also be applied to some of the other node symmetric interconnection structures defined on the symmetric group, when the aforementioned distance expression is available. 相似文献
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