Biased processing of emotional information in girls at risk for depression.

Researchers have documented that children of depressed mothers are at elevated risk for developing a depressive disorder themselves. There is currently little understanding, however, of what factors place these children at elevated risk. In the present study, the authors investigated whether never-disordered daughters whose mothers have experienced recurrent episodes of depression during their daughters' lifetime are characterized by biased processing of emotional information. Following a negative mood induction, participants completed an emotional-faces dot-probe task. Daughters at elevated risk for depression, but not control daughters of never-disordered mothers, selectively attended to negative facial expressions. In contrast, only control daughters selectively attended to positive facial expressions. These results provide support for cognitive vulnerability models of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mexican American middle school students' goal intentions in mathematics and science: A test of social cognitive career theory.

This study examined whether sociocontextual and sociocognitive variables explained the math/science goals of 409 Mexican American youth using a modified version of R. W. Lent, S. D. Brown, and G. Hackett's (1994) social cognitive career theory. Results from structural equation modeling indicated that the hypothesized model explained a significant amount of variance in math/science goals for both Mexican American girls and boys. Findings suggested that gender did not moderate relations among the variables in the hypothesized model. Results also suggested that most of the social cognitive career theory propositions tested were supported. Specifically, social class predicted math/science past performance accomplishments. Math/science past performance accomplishments and perceived parent support predicted math/science self-efficacy. Furthermore, math/science self-efficacy predicted math/science outcome expectations, and together with math/science interests, these sociocognitive variables predicted math/science interests and goals. Contrary to expectations, generation status, Anglo orientation, and Mexican orientation did not predict math/science past performance accomplishments, and past performance accomplishments did not predict math/science outcome expectations. Furthermore, Anglo orientation and perceived social support from parents, teachers, classmates, and a close friend did not predict math/science goals. Suggestions for future research and implications of the results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How does Bennett Woods Elementary School produce such high reading and writing achievement?

The authors developed a grounded theory about how a school serving relatively advantaged children produces high reading and writing achievement compared with schools serving similar populations of students. The school's faculty is reading and writing focused, and students experience many books as they receive explicit, demanding instruction (i.e., about how to read words, comprehend, write) connected to content learning. The school offers a positive, motivating environment. In sum, many elements that potentially supported achievement were identified, including explicit teaching of skills in the context of much reading, writing, and content learning, which is consistent with balanced perspectives on reading and writing development. A major hypothesis in the grounded theory is that even with relatively advantaged populations, great efforts may be required to produce high reading and writing achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age differences in item manipulation span: The case of letter-number sequencing.

The authors report 2 experiments in which they examined age differences in working memory tasks involving complex item manipulation (i.e., letter-number sequencing). In Experiment 1, age differences on tasks involving item manipulation were not greater than age differences on tasks requiring recall of items in the order in which they appeared, suggesting that older adults do not have difficulty with item manipulation per se. In Experiment 2, slower presentation rates increased age differences in item manipulation spans, although age differences at the fastest rate may be attributed to differences in strategy use. In both experiments, age differences were largest when participants were most likely to be remembering familiar sequences, suggesting that older adults may have difficulties dampening the representations of such sequences once they are activated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Longitudinal factor structure of posttraumatic stress symptoms related to intimate partner violence.

Confirmatory factor analysis (CFA) studies have suggested that a model of posttraumatic stress disorder (PTSD) that is characterized by 4 factors is preferable to competing models. However, the composition of these 4 factors has varied across studies, with 1 model splitting avoidance and numbing symptoms (e.g., D. W. King, G. A. Leskin, L. A. King, & F. W. Weathers, 1998) and the other including a dysphoria factor that combines numbing and nonspecific hyperarousal symptoms (L. J. Simms, D. Watson, & B. N. Doebbeling, 2002). Using the PTSD Checklist (F. W. Weathers, B. T. Litz, D. S. Herman, J. A. Huska, & T. M. Keane, 1993) and CFA, the authors compared these models with competing models. A model of PTSD with 4 intercorrelated factors of Intrusions, Avoidance, Dysphoria, and Hyperarousal was found superior among 396 medical patients who screened positive for intimate partner violence (IPV) and 405 women seeking services for IPV. Structural invariance testing indicated that this 4-factor model remains stable across service setting and time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adhesive forces significantly affect elastic modulus determination of soft polymeric materials in nanoindentation

The present study investigated the effects of adhesion on the elastic modulus determined from nanoindentation curves for soft polydimethylsiloxane (PDMS) elastomers with five different crosslink concentrations. Indentation load-displacement curves were obtained for samples of all concentrations at four different peak loads. All load-displacement curves were nearly linear, resulting in load independent contact stiffnesses (p < 0.003) for the range of loads tested. As a result, elastic modulus calculated from nanoindentation curves with the Hertz contact model exhibited significant differences (p < 0.004) both at different peak loads for a single PDMS concentration and between different PDMS concentrations at a single peak load (p < 0.001). The differences for different peak loads were attributed to the presence of substantial adhesive forces at the tip-sample interface. By taking these adhesive interactions into account with the Johnson, Kendall, Roberts (JKR) contact model, the differences in elastic modulus at different peak loads could be reconciled. Significant differences (p < 0.001) in moduli between different PDMS concentrations were still present. The results highlight the importance of considering adhesive forces in nanoindentation analyses of low modulus polymeric materials.     

散落在云南的日子

阳光下,圣洁的雪峰屹立着古老的沧桑,现代的神秘,让我一如既往地憧憬那天边的金色殿堂。大假。约驴友共赴春城。除了路途颠簸的两整天,剩余的八个日子有如繁星,轻轻地散落在云南的各个角落,以至长时间里几度提笔,也不曾找到自己被     

Remote electronic voting systems: an exploration of voters' perceptions and intention to use

Coupling telephone and web interfaces with computers for balloting outside the polling place, remote electronic voting systems (REVS) give the voter a choice: polling booth, absentee ballot, or remote voting. Not only does this e-Government technology raises issues such as security, voter participation, and accessibility, REVS technologies themselves differ in features and enabling conditions. How users (voters) perceive REVS's availability, mobility, accuracy, privacy protection, and ease of use, is likely to affect their use intention. Intention to use or not to use a voting technology can translate into a decision to vote or not – and there are no ‘do-overs’. We develop a model and report on a survey of potential voters – people waiting to be impaneled on a jury – in regard to the impact of REVS characteristics on voting intentions and how the two most discussed REVS technologies of telephone- and web-based interfaces are perceived.     

The optimal level of fuzz: case studies in a methodology for psychological research

Cognitive science research is hard to conduct, because researchers must take phenomena from the world and turn them into laboratory tasks for which a reasonable level of experimental control can be achieved. Consequently, research necessarily makes tradeoffs between internal validity (experimental control) and external validity (the degree to which a task represents behaviour outside of the lab). Researchers are thus seeking the best possible trade-off between these constraints, which we refer to as the optimal level of fuzz. We present two principles for finding the optimal level of fuzz, in research, and then illustrate these principles using research from motivation, individual differences and cognitive neuroscience.