Interracial contexts debilitate same-race face recognition

Social cognitive research has documented the integral role of social categories (e.g., race) in face processing. Activating a social category can lead perception and memory of faces to be biased in a category-consistent direction. The current research extends this past work, to test the hypothesis that making a social category salient can reduce subsequent face recognition. In two experiments, the current research finds that the typically superior same-race recognition is debilitated by making the same-race category salient. We find that when White-Americans self-categorize as ‘White,’ subsequent perceptual and memorial biases reduce the typically strong same-race recognition.     

A statistical decision model for sensory discrimination which predicts Weber’s law and other sensory laws: Some results of a computer simulation

A model for visual intensity threshold discrimination is described. Simplified assumptions represent the main features of the visual afferent paths. Discriminative responses are selected centrally by a statistical decision procedure, limited by the noise level. Noise arises from the irreducible physical variability of light, from spontaneous firing, and from variations in transmission in the afferent paths, These variations will tend to be positively correlated. The model was simulated on a computer: it correctly predicts the form of the Weber function (the relation between difference threshold and background intensity) and the features of spatial and temporal “summation”. It also shows that the function relating the central effect of a stimulus to its physical intensity is unlikely to be logarithmic or a power function with a small exponent.     

Involvement in Meaningful Activities and Self-Reported Aggression and Delinquency Among Inner-City Teenagers

Ninth grade students from an inner-city high school (n = 163) completed self-report measures assessing their participation in meaningful activities, behavioral problems, and locus of control. In multivariate analyses, Gender × Activity Level interaction effects were shown: males with higher levels of meaningful activity had significantly lower scores on aggression and delinquent behavior subscales than males with lower levels of meaningful activity. However, this relationship was not shown for females. Of youth who reported clinically significant levels of aggression and/or delinquency, females reported significantly higher levels of meaningful activities than males. Gender differences in findings and future research directions are discussed.     

真之形而上学

“真”是语言哲学的核心概念,由于该词本身的特性,它的语义特征在日常使用中并不明显。围绕“真”有许多讨论,形成不同理论。这样的讨论和理论既有语言学层面的问题,也有形而上学层面的问题。戴维特详细分析论述了这两个层面的差异,并试图说明二者的优劣以及孰为先孰为后。无论他的观点是不是正确,不管他的论证是不是充分,他的文章至少是一篇出色的综述,从中可以使我们大致领略当前关于真之形而上学是一种什么样的讨论。     

Intrinsic conflicts of interest in clinical research: a need for disclosure

Protection of human subjects from investigators' conflicts of interest is critical to the integrity of clinical investigation. Personal financial conflicts of interest are addressed by university policies, professional society guidelines, public standards, and government regulation, but "intrinsic conflict of interest"--conflicts of interest inherent in all clinical research--have received relatively less attention. Such conflicts arise in all clinical research endeavors as a result of the tension among professionals' responsibilities to their research and to their patients and both academic and financial incentives. These conflicts should be disclosed to research subjects and managed as assiduously as are financial conflicts of interest.     

The precedence effect in three species of birds (Melopsittacus undulatus, Serinus canaria, and Taeniopygia guttata)

The perceived locations of paired auditory images, simulating direct sounds and their echoes, have been recently studied in budgerigars (Melopsittacus undulatus; M. L. Dent & R. J. Dooling, 2003a, 2003b). In this article, the authors extend those experiments to include measurements of the precedence effect using a discrimination paradigm in two additional bird species: canaries (Serinus canaria) and zebra finches (Taeniopygia guttata). Although time courses of summing localization, localization dominance, and echo thresholds were similar across all species, budgerigars had slightly higher overall levels of discrimination. The results from these experiments add further support that the precedence effect in birds is similar to that found in other animals and that the ability to suppress echoes that might degrade localization and auditory object perception may be a general property of the vertebrate auditory system.     

Peritraumatic dissociation and PTSD severity: do event-related fears about death and control mediate their relation?

Relations among peritraumatic dissociation, PTSD severity, event-related fear (i.e. fear experienced during traumatic event) about death, and event-related fear about losing control were examined in the current study. Particular emphasis was placed on testing whether or not fears about death and losing control mediate the relation between peritraumatic dissociation and PTSD severity in a sample of 146 nontreatment-seeking university women. Results indicated that event-related fears about death and losing control accounted for the relation between peritraumatic dissociation and PTSD severity; that is, the effect of peritraumatic dissociation on PTSD severity was eliminated after controlling for these fears. Speculations about findings are discussed.     

On the ultra-high-strain rate shock deformation in copper single crystals: multiscale dislocation dynamics simulations

Multiscale dislocation dynamics plasticity (MDDP) calculations are carried out to simulate the mechanical response of copper single crystals that have undergone shock loading at high strain rates ranging from 1?×?10⁶ to 1?×?10¹⁰?s^?1. Plasticity mechanisms associated with both the activation of pre-existing dislocation sources and homogeneous nucleation of glide loops are considered. Our results show that there is a threshold strain rate of 10⁸?s^?1 at which the deformation mechanism changes from source activation to homogeneous nucleation. It is also illustrated that the pressure dependence on strain rate follows a one-fourth power law up to 10⁸?s^?1 beyond which the relationship assumes a one-half power law. The MDDP computations are in good agreement with recent experimental findings and compare well with the predictions of several dislocation-based continuum models.