Sex Differences and Individual Differences in Cognitive Performance and Their Relationship to Endogenous Gonadal Hormones and Gonadotropins.

Sexually dimorphic cognitive performance in men (n=42) and women (n=42) was related to testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin, measured in 10-ml blood samples collected between 0900 and 1030 and, among women, during the follicular phase of the menstrual cycle. Significant sex differences favored men on spatial tasks (Mental Rotation and Judgment of Line Orientation) and on an inhibition task and favored women on a verbal task (category fluency). However, there were no significant relationships between any of the hormones and cognitive performance, suggesting that there are few, if any, consistent, substantial relationships between endogenous, nonfluctuating levels of gonadal hormones or gonadotropins and these cognitive abilities in men or women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuroticism and brain responses to anticipatory fear.

Personality is known to influence cognitive and affective functioning as well as the risk of psychiatric disorders. Exploration of the neurobiological correlates of personality traits has the potential to enhance understanding of their significance in development of related psychopathological states. The authors examined the association between individual differences in neuroticism and brain activity in response to threat of electric shocks. Fourteen right-handed healthy men underwent functional MRI during a 5-min experiment that involved repeated presentations of two 30-s alternating conditions. In 1 of these conditions, subjects were told to expect mild but painful electric shocks; there was no possibility of receiving shocks in the other condition. The results revealed that neuroticism correlated positively with the ratings of fear of shock and negatively (indicating suppression) with brain activity from safe to shock conditions in the anterior and posterior cingulate, superior/middle temporal gyrus extending to the hippocampus, precuneus, putamen, thalamus, and middle occipital gyrus. The observations support recent psychophysiological research that has demonstrated reduced processing of pain in subjects with higher levels of neuroticism, especially the anxiety component of this trait. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characterization of dual‐scale fiber mats for unsaturated flow in liquid composite molding

The drooping inlet‐pressure history during 1D filling experiments has been used in the past to detect the onset of the unsaturated flow in certain stitched mats, called dual‐scale mats, during mold‐filling in liquid composite molding. In this study, one such triaxial stitched mat was tested for unsaturated flow and manifests the characteristic inlet‐pressure droop that increases with fiber mat compression. A correlation between the previously proposed dimensionless numbers pore volume ratio (γ) and sink effect index (ψ) and the droop in the inlet pressure history was also sought. By studying the micrographs of the composite samples, γ and ψ were measured for the biaxial and triaxial stitched mats at various states of compression. The observation that the droop in the inlet‐pressure profiles increase with an increase in γ and ψ establishes the two dimensionless numbers, along with the presence of straight channels aligned with the flow direction, as good predictors of the unsaturated flow in the dual‐scale fiber mats. POLYM. COMPOS. 26:756–769, 2005. © 2005 Society of Plastics Engineers