Endogenous testosterone concentration, mental rotation, and size of the corpus callosum in a sample of young Hungarian women

In the present study brain laterality, hemispheric communication, and mental rotation performance were examined. A sample of 33 women were tested for a possible linear relationship of testosterone level and mental rotation with structural background of the brain. Subjects with a smaller splenial area of corpus callosum tended to have lower levels of testosterone (r =.37, p<.05). However, there were no significant differences in mean scores of mental rotation of object and hand between groups with high and low levels of testosterone. There was a significant difference in relative size of the 6th area (slice) of the corpus callosum between groups with good and poor scores on mental rotation of an object and also in relative size of the 4th and 5th slices of the corpus callosum between groups on mental rotation of the hand. The good and poor scorers' show different relations with the measures of the corpus. The mental rotation of hand was associated with the parietal areas of the corpus callosum, while the mental rotation of object was associated only with the occipital area. These observations suggest that higher testosterone levels may be associated with a larger splenial area, which represents an important connection between the parieto-occipitocortical areas involved in activation of mental images. Further srudy is encouraged.     

Variation with density of the transport properties of YBaCuO superconductors

Abstract

The dependence of the normal-state resistivity, resistive superconducting transition (T _c, ΔT _c), and of the upper critical-field slope (dH _c2/dT|T=T_c) on density has been investigated for several YBa₂Cu₃O_9-x(x?2.1) samples. The resistivity decreases rapidly with increasing density, whereas T _c and ΔT _c are rather insensitive to a change in density. dH _c2/dT|T_c depends sensitively on the preparation conditions. The implications of these results both for the evaluation of the parameters relevant to the understanding of the nature of superconductivity and for the technological applications of granular superconductors are briefly discussed.     

How immigrant adolescents' self‐views in school and family context relate to academic success in Germany

Immigrants' sense of self can be derived both from being members of their ethnic in‐group and their country of residence. We examined how the ways in which immigrant adolescents integrate these self‐views in relation to academic success in German schools. Students describe themselves at school and when with family. Using a standardized literacy performance test, analyses revealed that immigrants whose school‐related self‐view did not include Germany were less successful: Students who described their self as including both aspects of their ethnic group and Germany, and students who saw themselves predominantly as German, outperformed students with purely ethnic school‐related selves. As expected, though, an ethnic family‐related self‐view did not have a negative impact on scholastic achievements.     

Child Personality as Moderator of Outcome in a School‐based Intervention for Preventing Externalising Behaviour

Studying moderators of intervention effects is essential to elucidate what works for whom. The present study investigated whether child personality moderates short‐term and follow‐up effects of an individualised preventive school‐based intervention for children with externalising behaviour. The sample consisted of 48 schools, with 264 fourth‐grade children displaying externalising behaviour (M_age = 10.2 years), randomly assigned to the intervention (n = 191) or no intervention control (n = 73) condition. Teachers and children reported at pretest, posttest and follow‐up test about reactive and proactive aggression. Child personality was assessed by teachers at pretest. Child conscientiousness moderated short‐term intervention effects, indicating that more organised and planful children benefited more from the intervention. Child extraversion moderated both short‐term and follow‐up intervention effects, with low extraverted children showing larger effects. These results affirm the importance of including personality as moderator of intervention effects in future studies, as interventions adapted to specific child traits might yield larger effects. Copyright © 2012 John Wiley & Sons, Ltd.     

A Note on Bisimulation and Modal Equivalence in Provability Logic and Interpretability Logic

Provability logic is a modal logic for studying properties of provability predicates, and Interpretability logic for studying interpretability between logical theories. Their natural models are GL-models and Veltman models, for which the accessibility relation is well-founded. That’s why the usual counterexample showing the necessity of finite image property in Hennessy-Milner theorem (see [1]) doesn’t exist for them. However, we show that the analogous condition must still hold, by constructing two GL-models with worlds in them that are modally equivalent but not bisimilar, and showing how these GL-models can be converted to Veltman models with the same properties. In the process we develop some useful constructions: games on Veltman models, chains, and general method of transformation from GL-models/frames to Veltman ones.     

The Self-Knowledge Gambit

If we hold that perceiving is sufficient for knowing, we can raise a powerful objection to dreaming skepticism: Skeptics assume the implausible KK-principle, because they hold that if we don’t know whether we are dreaming or perceiving p, we don’t know whether p. The rejection of the KK-principle thus suggests an anti-skeptical strategy: We can sacrifice some of our self-knowledge—our second-order knowledge—and thereby save our knowledge of the external world. I call this strategy the Self-Knowledge Gambit. I argue that the Self-Knowledge Gambit is not satisfactory, because the dreaming skeptic can avail herself of a normative counterpart to the KK-principle: When we lack second-order knowledge, we should suspend our first-order beliefs and thereby give up any first-order knowledge we might have had. The skeptical challenge is essentially a normative challenge, and one can raise it even if one rejects the KK-Principle.