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271.
272.
Factors that promote healthy relationships have been understudied. The objective of this study is to examine mother–child verbal and nonverbal communication (separately), relationship quality and children's positive social behaviours in an at-risk sample framed within the developmental psychopathology approach. Mothers are part of a 35-year longitudinal prospective study who, as children, were rated by peers on measures of aggression and social withdrawal. These mothers, with their own 9- to 13-year-old children, participated in conflict and game-playing tasks. Verbal and nonverbal communication were coded separately using systematic observational measures. Maternal childhood histories of aggression and withdrawal predicted poorer dyad verbal communication, relationship quality and children's positive social behaviours. Frequently displayed positive verbal and nonverbal communication were associated with better relationship quality and children's positive social behaviours. The results highlight the unique contributions of verbal and nonverbal communication to adaptive development and to promoting healthy relationships in at-risk families during middle-childhood.  相似文献   
273.
Eighty-three newborns (M GA = 37 weeks) were assigned to depressed (N = 47) and nondepressed mother (N = 36) groups based on Beck Depression Inventory (BDI) scores. The Brazelton Neonatal Assessment Scale was administered to the infants within 24 hours after birth. Infants of depressed mothers demonstrated poorer performance on the orientation cluster. Further analysis of the orientation cluster items revealed inferior orientation to the inanimate stimuli. Infants of depressed mothers also showed less motor tone and activity and more irritability and less robustness and endurance (unavailability, lethargy, and stress behaviors) during the examination.  相似文献   
274.
IQs were correlated with the z score of suicide rate minus z score of homicide rate using nine regions of the world--established market economies, formerly socialized Europe, India, China, other Asian nations, Sub-Saharan Africa, Latin America/Caribbean, Middle East Crescent, and the USA. Correlations were .85 and .83 with crude rates and age-adjusted rates, respectively. The homicide findings are consistent with previous research in individual countries showing that less intelligent persons commit homicide more often. However, the present findings of a positive correlation between IQ and suicide rates are the opposite of what has been found in the more definitive studies within countries. Explanations for the apparent paradox and for the findings more generally were offered.  相似文献   
275.
The purpose of this paper is to report the outcome of a collaborative project between the Fragile X Research and Treatment Center at the Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute at the University of California at Davis, the National Fragile X Foundation (NFXF), and the Centers for Disease Control and Prevention (CDC). The objective of this collaboration was to develop and disseminate protocols for genetic counseling and cascade testing for the multiple disorders associated with the fragile X mental retardation 1 (FMR1) mutation. Over the last several years, there has been increasing insight into the phenotypic range associated with both the premutation and the full mutation of the FMR1 gene. To help develop recommendations related to screening for fragile X-associated disorders, four, two day advisory focus group meetings were conducted, each with a different theme. The four themes were: (1) fragile X-associated tremor/ataxia syndrome (FXTAS); (2) premature ovarian failure (POF) and reproductive endocrinology; (3) psychiatric, behavioral and psychological issues; and (4) population screening and related ethical issues.  相似文献   
276.
Recent evidence has suggested that new objects capture attention solely because they are typically accompanied by a unique luminance transient. In the present study, we presented a stationary pattern mask after an array of placeholders but before a subsequent search display. This allowed all of the search elements to be presented simultaneously, thereby eliminating the unique luminance transient associated with the appearance of any new objects. Under these circumstances, new objects still captured attention. In another experiment, we jiggled the mask. This caused new objects to lose their advantage. We discuss implications for the importance of new objects, and the attentional consequences of motion.  相似文献   
277.
Despite considerable research on assessing preferences among people with severe disabilities, relatively little investigatory attention has been directed to preferences in supported work situations. We evaluated a protocol for identifying work preferences among adults with severe disabilities in supported jobs. The protocol involved obtaining opinions of support staff regarding most and least preferred tasks of a supported worker, conducting a multi‐task preference assessment and then if necessary, a paired‐task assessment for workers for whom the former assessment did not reveal work preferences. For the 12 participating workers, the multi‐task assessment revealed preferences for 7 of the workers and subsequently, the paired‐task assessment revealed preferences for 4 of the 5 remaining workers. The former assessment required 40% less time than the latter. Staff opinion required much less time to obtain, but accurately identified preferences (based on validation through systematic assessment) only somewhat consistently. Results are discussed regarding guidelines for efficiently identifying supported work preferences, and future research areas are noted for developing more definitive guidelines. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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279.
Marshall Abrams 《Synthese》2009,166(1):21-40
Organisms’ environments are thought to play a fundamental role in determining their fitness and hence in natural selection. Existing intuitive conceptions of environment are sufficient for biological practice. I argue, however, that attempts to produce a general characterization of fitness and natural selection are incomplete without the help of general conceptions of what conditions are included in the environment. Thus there is a “problem of the reference environment”—more particularly, problems of specifying principles which pick out those environmental conditions which determine fitness. I distinguish various reference environment problems and propose solutions to some of them. While there has been a limited amount of work on problems concerning what I call “subenvironments”, there appears to be no earlier work on problems of what I call the “whole environment”. The first solution I propose for a whole environment problem specifies the overall environment for natural selection on a set of biological types present in a population over a specified period of time. The second specifies an environment relevant to extinction of types in a population; this kind of environment is especially relevant to certain kinds of long-term evolution.  相似文献   
280.
This review focuses on synaptic depression at sensory neuron-to-motor neuron synapses in the defensive withdrawal circuit of Aplysia as a model system for analysis of molecular mechanisms of sensory gating and habituation. We address the following topics:1. Of various possible mechanisms that might underlie depression at these sensory neuron-to-motor neuron synapses in Aplysia, historically the most widely-accepted explanation has been depletion of the readily releasable pool of vesicles. Depletion is also believed to account for synaptic depression at long interstimulus intervals in a variety of other systems.2. Multiple lines of evidence now indicate that vesicle depletion is not an important contributing mechanism to synaptic depression at Aplysia sensory neuron-to-motor neuron synapses. More generally, it appears that vesicle depletion does not contribute substantially to depression that occurs with those stimulus patterns that are typically used in studying behavioral habituation.3. Recent evidence suggests that at these sensory neuron-to-motor neuron synapses in Aplysia, synaptic depression is mediated by an activity-dependent, but release-independent, switching of individual release sites to a silent state. This switching off of release sites is initiated by Ca2+ influx during individual action potentials. We discuss signaling proteins that may be regulated by Ca2+ during the silencing of release sites that underlies synaptic depression.4. Bursts of 2–4 action potentials in presynaptic sensory neurons in Aplysia prevent the switching off of release sites via a mechanism called “burst-dependent protection” from synaptic depression.5. This molecular switch may explain the sensory gating that allows animals to discriminate which stimuli are innocuous and appropriate to ignore and which stimuli are more important and should continue to elicit responses.  相似文献   
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