Relative Contributions of the Male and the Female to Sexual Behavior and Reproductive Success in the Japanese Quail (Coturnix japonica).

Two contrasting investigative techniques provided evidence consistent with the interpretation that female quail (Coturnix japonica) regulate male copulatory behavior by the duration of their immobility and through this behavioral mechanism they also control the rate of fertilization of their eggs. In Experiment 1, copulation tests with males and females from different genetic lines showed that the type of female that participated in a copulatory test significantly influenced the latency of the male's grab, mount, and cloacal contact responses and also determined the efficiency of the male's copulatory behavior. These measures of male performance were correlated with female immobility in Experiment 2, which used a more homogeneous population of quail. Furthermore, 2 of these measures (copulatory efficiency and the latency to make cloacal contact) were correlated with fertilization rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trajectories leading to school-age conduct problems.

The present study applied a semiparametric mixture model to a sample of 284 low-income boys to model developmental trajectories of overt conduct problems from ages 2 to 8. As in research on older children, 4 developmental trajectories were identified: a persistent problem trajectory, a high-level desister trajectory, a moderate-level desister trajectory, and a persistent low trajectory. Follow-up analyses indicated that initially high and low groups were differentiated in early childhood by high child fearlessness and elevated maternal depressive symptomatology. Persistent problem and high desister trajectories were differentiated by high child fearlessness and maternal rejecting parenting. The implications of the results for early intervention research are discussed, with an emphasis on the identification of at-risk parent-child dyads. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Uncertainty Matters: Computer Models at the Science–Policy Interface

The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However, despite the advantages modelling presents, the integration of information derived from models into policy is far away from being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying out management plans at regional and national scale. We suggest that the solution to integrate modelling information into policy formulation lies on both the modelling and the policy-making communities.     

Heterogeneity effects in visual search predicted from the group scanning model.

The group scanning model of feature integration theory suggests that Ss search visual displays serially by groups, but process items within each group in parallel. Group size is determined by the discriminability of the targets in the background of distractors. When the target is poorly discriminable, the size of the scanned group will be small, and search will be slow. The model predicts that group size will be smallest when targets of an intermediate value on a perceptual dimension are presented in a heterogeneous background of distractors that have higher and lower values on the same dimension. Experiment 1 (30 Ss) demonstrates this effect; Exp 2 (12 Ss) controls for a possible confound of decision complexity in Exp 1. For simple feature targets, the group scanning model provides a good account of the visual search process. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Frontal brain activation in repressors and nonrepressors.

Assessed whether resting anterior asymmetry would discriminate individual differences in repressive-defensive coping styles. In 2 sessions, resting electroencephalogram was recorded from female adults during 8 60-sec baselines. Ss were classified as repressors or nonrepressors on the basis of scores on the Marlowe-Crowne Social Desirability Scale (MC), the State-Trait Anxiety Inventory (STAI), and the Beck Depression Inventory (BDI). In midfrontal and lateral frontal sites, repressors demonstrated relative left hemisphere activation when compared with other groups. The MC, but not the STAI or the BDI, contributed unique variance to frontal asymmetry. Relative left frontal activation may be linked to a self-enhancing regulatory style that promotes lowered risk for psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The vulnerability of geometric sequences based on fields of odd characteristic

A new method of cryptologic attack on binary sequences is given, using their linear complexities relative to odd prime numbers. We show that, relative to a particular prime number p, the linear complexity of a binary geometric sequence is low. It is also shown that the prime p can be determined with high probability by a randomized algorithm if a number of bits much smaller than the linear complexity is known. This determination is made by exploiting the imbalance in the number of zeros and ones in the sequences in question, and uses a new statistical measure, the partial imbalance.This project was sponsored by the National Security Agency under Grant No. MDA904-91-H-0012. The United States Government is authorized to reproduce and distribute reprints notwithstanding any copyright notation hereon.     

Envelope glycoprotein gp120 of human immunodeficiency virus type 1 alters ion transport in astrocytes: implications for AIDS dementia complex

Infection by human immunodeficiency virus type 1 (HIV-1) is often complicated by a variety of neurological abnormalities. The most common clinical syndrome, termed acquired immunodeficiency syndrome (AIDS) dementia complex, presents as a subcortical dementia with cognitive, motor, and behavioral disturbances and is unique to HIV-1 infection. The pathogenesis of this syndrome is poorly understood but is believed to involve interactions among virally infected macrophages/microglia, astrocytes, and neurons. In this study, we show that exposure of primary rat and human astrocytes to heat-activated HIV-1 virions, or to eukaryotically expressed HIV-1 and HIV-2 envelope glycoproteins (gp120) stimulates amiloride-sensitive Na+/H+ antiport, potassium conductance, and glutamate efflux. These effects are blocked specifically by amiloride, an inhibitor of Na+/H+ antiport and by the selective removal of gp120 with immobilized monoclonal antibody. As a result of modulation of astrocytic function by gp120, the ensuing neuronal depolarization and glutamate exposure could activate both voltage-gated and N-methyl-D-aspartate-regulated Ca2+ channels, leading to increases in intraneuronal Ca2+ and neuronal death. These findings implicate the astrocyte directly in the pathogenesis of AIDS dementia complex.     

Self-efficacy expectations predict survival for patients with chronic obstructive pulmonary disease.

Evaluated the validity of self-efficacy expectations as predictors of mortality for 119 patients with chronic obstructive pulmonary disease. Ss completed 4 physiological measures that represent common clinical indicators of disease severity: forced expiratory volume in 1 s(FEV1.0), arterial blood gas measurement of resting partial pressure of oxygen (PaO?), single-breath diffusing capacity (DLCO), and maximum oxygen uptake (V02max) during exercise. In addition, self-reported self-efficacy expectation for walking on a treadmill was measured. Self-efficacy was a significant univariate predictor of 5-yr survival. However, when controlling for FEV1.0 in multivariate survival analysis, self-efficacy had only a marginal effect. Simple self-report scales may provide significant information about health status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eyewitness persuasion: How and how well do fact finders judge the accuracy of adults' and children's memory reports?

Children (aged 5–6 and 9–10 yrs) and adults participated in an eventful laboratory session and provided memory reports of the session. In 3 experiments, college students and parents viewed videotapes of highly accurate and highly inaccurate reports. In 2 experiments, these "fact finders" rated adult witnesses more believable and accurate than younger child witnesses, even when both groups were equally accurate. Perceptions of confidence and consistency mediated credibility judgments. Accurate witnesses were judged more believable and accurate than inaccurate witnesses. Higher perceived confidence, longer free recall, and fewer memory failure admissions were associated with more accurate adult memory reports. Fact finders overused confidence and underused the other cues in achieving modest accuracy discernment. The results suggest how strong and weak memory reports differ and how fact finders may learn to differentiate them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)