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991.
Assessed the impact of school-based social competence training on skills, social adjustment, and self-reported substance use of 282 6th and 7th graders. Training emphasized broad-based competence promotion in conjunction with domain-specific application to substance abuse prevention. The 20-session program comprised 6 units: stress management, self-esteem, problem solving, substances and health information, assertiveness, and social networks. Findings indicated positive training effects on Ss' skills in handling interpersonal problems and coping with anxiety. Teacher ratings revealed improvements in Ss' constructive conflict resolution with peers, impulse control, and popularity. Self-report ratings indicated gains in problem-solving efficacy. Results suggest some preventive impact on self-reported substance use intentions and excessive alcohol use. In general, the program was found to be beneficial for both inner-city and suburban students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
This paper investigates cognitive and physiological precursors of orthostatic panic (OP), that is, panic upon standing, which is a key complaint among traumatized Cambodian refugees. Prior research links OP to hypotension (lower blood pressure) and catastrophic cognitions. A clinical sample of 102 Cambodian refugees were assessed for posttraumatic stress disorder (PTSD), recent OP attacks, and anticipatory anxiety before engaging in an orthostatic challenge (OC) task during which they were monitored for blood pressure. After the task, they were assessed for OC-induced culture-related catastrophic cognitions, flashbacks, and panic attacks. We found that participants with recent OP (n = 60) had more PTSD, greater anticipatory anxiety before the OC, a larger drop in systolic blood pressure during the OC, more OC-induced catastrophic cognitions and flashbacks, and more severe OC-induced panic attack symptoms. Regression models showed that the severity of OC-induced panic symptoms was predicted by the magnitude of SBP drop and mediated by more severe catastrophic cognitions and flashbacks. Implications of the findings for cross-cultural psychopathology research and the treatment of both panic and PTSD in Cambodian refugees are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
Since the introduction of sodium metabisulfite as a food preservative, it has been associated with several idiosyncratic reactions (eg, bronchospasm, oculonasal symptoms, and urticaria/angioedema) in sulfite-sensitive individuals. The pathogenic mechanism of these reactions is not yet understood. We report the case of two crewmen on a shrimp trawler who were found dead in the ship's hold. Their deaths had occurred while they were applying dry sodium metabisulfite, referred to as "shrimp dip" in the shrimping industry. Postmortem examinations showed diffuse pulmonary edema consistent with death secondary to asphyxia. Associated findings were visceral congestion. Although it is possible to measure death from sodium metabisulfite with available records, its potential morbidity cannot be estimated. It is known that sodium metabisulfite can react with acids and water, releasing toxic sulfur dioxide (SO2) gas. In addition, SO2 gas reacts with respiratory tissue forming sulfureous acid, and inducing a pulmonary reaction causing hypoxemia. Furthermore, sodium metabisulfite, compared with sodium bisulfite, has a much greater propensity to release SO2 gas. We conclude that there is a need for improved education regarding the potential side effects of sodium metabisulfite, thus eliminating needless occupational morbidity and mortality.  相似文献   
994.
The relationship of depressed mood to cognitive disturbance in HIV infection was examined in a sample of 139 homosexual men. Ss were grouped according to the classification of the Centers for Disease Control: 39 were in Group IV, 62 were in Group II or Group III, and 38 were HIV-negative. Ss completed the Profile of Mood States and 10 neuropsychological tests. Analysis employing a classification approach indicated that, although symptoms of depression and neuropsychological impairment were more common in Ss who were HIV-positive, particularly those classified as Group IV, there were no systematic relationships between depression and neuropsychological impairment. Depressed mood and cognitive disturbance each seem to have unique associations to HIV illness status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
996.
Develops 3 hypotheses to explain the role of construal processes in conformity behavior. According to the preconformity change of meaning hypothesis, social influence leads to changes in situational construal that precede and mediate conformity behavior; according to the postconformity change of meaning hypothesis, construal change follows and justifies conformity; and according to the construal-consistency hypothesis, preexisting situational construal distinguishes those who conform from those who dissent. Four experimental studies with varying methodology and involving a total of 361 undergraduate students were performed to test these hypotheses. The results of all studies provide strong evidence for postconformity change of meaning effects. Discussion centers on possible domains in which the different construal mechanisms might operate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
Objective: Previous research has demonstrated that hypoglycemia causes reaction times to be slower and more variable. Reaction time tests, however, use multiple cognitive and noncognitive processes. This study is the first to use a validated sequential sampling model (diffusion model) applied to results obtained from a simple 2-choice task in adult humans to assess the effects of hypoglycemia on the basic parameters of decision making. Method: Fourteen adult volunteers were tested on a numerosity discrimination task with and without reduced blood glucose concentrations. The results were analyzed with a model that dissects the components of processing that underlie decisions: the quality of the information on which a decision is based (drift rate), the critical amount of evidence that must be accumulated before a decision is made (boundary separation), and the time taken by nondecision processes. Results: Hypoglycemia resulted in a reduction of mean drift rate from 0.290 to 0.211, t(13) = 4.10, p  相似文献   
998.
在设计的关联性方面有一个逐步发展的认识:设计与其它学科的关联,不同设计学科之间的交集即界线正日益被质疑和跨越.然而,在我看来,目前最重要的界线不仅是可以被交叉跨越,而且专业和业余之间,更确切地说是设计师和用户之间的界线正在被消除.近代的设计方法已强调了以用户为中心的方法的重要性,但没有考虑到一点,即设计师和用户从本质上来说是相同的.这个观点的转变潜在地改变了设计教育、设计实践和设计消费.本文描述了一个最近的展览,游客到画廊不仅有机会在屏幕上创作产品设计,而且可以把它们进行实际的加工并展示为这个展览中的一部分.本文阐述设计师和手工艺者所做的选择形成了这类系统,并探讨了专业和业余的创造性活动之间的紧张关系,同时也探讨了设计教育中被提出的问题和不仅消除不同设计学科之间而且消除设计师用户之间的区别这个体系的潜在影响.  相似文献   
999.
SQL injection     
Bisson  Roger 《ITNOW》2005,47(2):25
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1000.
Optimal Structure from Motion: Local Ambiguities and Global Estimates   总被引:1,自引:1,他引:1  
Structure From Motion (SFM) refers to the problem of estimating spatial properties of a three-dimensional scene from the motion of its projection onto a two-dimensional surface, such as the retina. We present an analysis of SFM which results in algorithms that are provably convergent and provably optimal with respect to a chosen norm.In particular, we cast SFM as the minimization of a high-dimensional quadratic cost function, and show how it is possible to reduce it to the minimization of a two-dimensional function whose stationary points are in one-to-one correspondence with those of the original cost function. As a consequence, we can plot the reduced cost function and characterize the configurations of structure and motion that result in local minima. As an example, we discuss two local minima that are associated with well-known visual illusions. Knowledge of the topology of the residual in the presence of such local minima allows us to formulate minimization algorithms that, in addition to provably converge to stationary points of the original cost function, can switch between different local extrema in order to converge to the global minimum, under suitable conditions. We also offer an experimental study of the distribution of the estimation error in the presence of noise in the measurements, and characterize the sensitivity of the algorithm using the structure of Fisher's Information matrix.  相似文献   
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