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431.
Recent work in the learned helplessness paradigm suggests that neuronal sensitization and fatigue processes are critical to producing the behavioral impairment that follows prolonged exposure to an unsignaled inescapable stressor such as a series of electric tail shocks. Here we discuss how an interaction between serotonin (5-HT) and corticosterone (CORT) sensitizes GABA neurons early in the pretreatment session with inescapable shock. We propose that this process eventually depletes GABA, thus removing an important form of inhibition on excitatory glutamate transmission in the amygdala, hippocampus, and frontal cortex. When rats are re-exposed to shock during shuttle-escape testing 24 hrs later, the loss of inhibition (as well as other excitatory effects) results in unregulated excitation of glutamate neurons. This state of neuronal over-excitation rapidly compromises metabolic homeostasis. Metabolic fatigue results in compensatory inhibition by the nucleoside adenosine, which regulates neuronal excitation with respect to energy availability. The exceptionally potent form of inhibition associated with adenosine receptor activation yields important neuroprotective benefits under conditions of metabolic failure, but also precludes the processing of information in fatigued neurons. The substrates of adaptive behavior are removed; performance deficits ensue.  相似文献   
432.
A Big Regulatory Tool-Box for a Small Technology   总被引:1,自引:0,他引:1  
There is little doubt that the development and commercialisation of nanotechnologies is challenging traditional state-based regulatory regimes. Yet governments currently appear to be taking a non-interventionist approach to directly regulating this emerging technology. This paper argues that a large regulatory toolbox is available for governing this small technology and that as nanotechnologies evolve, many regulatory advances are likely to occur outside of government. It notes the scientific uncertainties facing us as we contemplate nanotechnology regulatory matters and then examines the notion of regulation itself, suggesting new ways to frame our understanding of both regulation and the regulatory tools relevant to nanotechnologies. By drawing upon three different conceptual lenses of regulation, the paper articulates a wide range of potential regulatory tools at hand. It also focuses particularly on the ways various tools are currently being used or perhaps may be employed in the future. The strengths and weaknesses characterising these tools is examined as well as the different actors involved. The paper concludes that we will increasingly face debate over what is likely to work most effectively in regulating nano technologies, the legitimacy of these different potential approaches, and the speed at which these different regimes may be employed.
Graeme A. HodgeEmail:
  相似文献   
433.
DEBI, or the Diffusion of Effective Behavioral Interventions is the largest centralized effort to diffuse evidence-based prevention science to fight HIV/AIDS in the United States. DEBI seeks to ensure that the most effective science-based prevention interventions are widely implemented across the country in community-based organizations. Thus, this is a particularly timely juncture in which to critically reflect on the extent to which known principles of community collaboration have guided key processes associated with the DEBI rollout. We review the available evidence on how the dissemination of packaged interventions is necessary but not sufficient for ensuring the success of technology transfer. We consider additional principles that are vital for successful technology transfer, which were not central considerations in the rollout of the DEBI initiative. These issues are: (1) community perceptions of a top-down mode of dissemination; (2) the extent to which local innovations are being embraced, bolstered, or eliminated; and (3) contextual and methodological considerations that shape community preparedness. Consideration of these additional factors is necessary in order to effectively document, manage, and advance the science of dissemination and technology transfer in centralized prevention efforts within and outside of HIV/AIDS.  相似文献   
434.
Communities are increasingly being required by state and federal funders to achieve outcomes and be accountable, yet are often not provided the guidance or the tools needed to successfully meet this challenge. To improve the likelihood of achieving positive outcomes, the Getting To Outcomes (GTO) intervention (manual, training, technical assistance) is designed to provide the necessary guidance and tools, tailored to community needs, in order to build individual capacity and program performance. GTO is an example of a Prevention Support System intervention, which as conceptualized by the Interactive Systems Framework, plays a key role in bridging the gap between prevention science (Prevention Synthesis and Translation System) and prevention practice (Prevention Delivery System). We evaluated the impact of GTO on individual capacity and program performance using survey- and interview-based methods. We tracked the implementation of GTO and gathered user feedback about its utility and acceptability. The evaluation of GTO suggests that it can build individual capacity and program performance and as such demonstrates that the Prevention Support System can successfully fulfill its intended role. Lessons learned from the implementation of GTO relevant to illuminating the framework are discussed.  相似文献   
435.
The functional specificity of the brain region known as the Visual Word Form Area (VWFA) was examined using fMRI. We explored whether this area serves a general role in processing symbolic stimuli, rather than being selective for the processing of words. Brain activity was measured during a visual 1-back task to English words, meaningful symbols (e.g., $, %), digits, words in an unfamiliar language (Hebrew), and geometric control stimuli. Mean activity in the functionally defined VWFA, as well as a pattern of whole-brain activity identified using a multivariate technique, did not differ for words and symbols, but was distinguished from that seen with other stimuli. However, functional connectivity analysis of this region identified a network of regions that was specific to words, including the left hippocampus, left lateral temporal, and left prefrontal cortex. Results support the hypothesis that activity in the VWFA plays a general role in processing abstract stimuli; however, the left VWFA is part of a unique network of brain regions active only during the word condition. These findings suggest that it is the neural "context" of the VWFA, i.e., the broader activity distributed in the brain that is correlated with VWFA, that is specific for visual word representation, not activity in this brain region per se.  相似文献   
436.
The current study examined the relation between intimate partner violence (IPV) and children's reactions to a stressful peer interaction in a community-based sample. The moderating role of parental emotion coaching in buffering children from negative reactions to a peer was also examined. Children participated in a peer provocation paradigm and mothers completed the Parent Meta-Emotion Interview. Both adaptive (i.e., laughing, ignoring) and maladaptive (i.e., hostile/challenging, odd behaviors) reactions to the provocative peer were examined. IPV was positively related to children's laughing and odd behaviors but was unrelated to ignoring and hostile/challenging behaviors. Additionally, emotion coaching was found to moderate relations between IPV and children's laughing and odd behaviors. The importance of understanding protective factors in families experiencing IPV and of developing emotion coaching parenting programs is discussed.  相似文献   
437.
Research consistently shows that children exposed to interparental conflict are at-risk for experiencing psychopathology. Establishing a link, however, between interparental conflict and maladjustment is not the same as understanding how specific outcomes manifest. Therefore, we examined the relation of interparental conflict and appraisal with adolescent outcome with 169 high school students (ages 14–19 years). Specifically, threat and self-blame appraisals were hypothesized to mediate the relation between interparental conflict and both adaptive and maladaptive outcomes. Results suggest that threat partially mediated the relation between interparental conflict and externalizing problems, interparental conflict and internalizing problems, and interparental conflict and adaptive behaviors. Additionally, self-blame appears to partially mediate the relation between interparental conflict and internalizing problems. Implications of the current findings are discussed.  相似文献   
438.
The auditory conditioned stimulus (CS) pathway that is necessary for delay eyeblink conditioning was investigated using reversible inactivation of the medial auditory thalamic nuclei (MATN) consisting of the medial division of the medial geniculate (MGm), suprageniculate (SG), and posterior intralaminar nucleus (PIN). Rats were given saline or muscimol infusions into the MATN contralateral to the trained eye before each of four conditioning sessions with an auditory CS. Rats were then given four additional sessions without infusions to assess savings from the initial training. All rats were then given a retention test with a muscimol infusion followed by a recovery session. Muscimol infusions through cannula placements within 0.5 mm of the MGm prevented acquisition of eyeblink conditioned responses (CRs) and also blocked CR retention. Cannula placements more than 0.5 mm from the MATN did not completely block CR acquisition and had a partial effect on CR retention. The primary and secondary effects of MATN inactivation were examined with 2-deoxy-glucose (2-DG) autoradiography. Differences in 2-DG uptake in the auditory thalamus were consistent with the cannula placements and behavioral results. Differences in 2-DG uptake were found between groups in the ipsilateral auditory cortex, basilar pontine nuclei, and inferior colliculus. Results from this experiment indicate that the MATN contralateral to the trained eye and its projection to the pontine nuclei are necessary for acquisition and retention of eyeblink CRs to an auditory CS.  相似文献   
439.
Neighborhood context, including the physical and social environment, has been implicated as important contributors to positive youth development. A transactional approach to neighborhood asserts that place and people are mutually constitutive; negative perceptions of place are intrinsically bound with negative portrayals of stigmatized groups, including youth. Adult perceptions of neighborhood youth may contribute to an increased sense of alienation and youth antisocial behavior. This study uses street‐intercept interviews with adults (N = 408) to examine the relationship between neighborhood conditions and adult support for neighborhood youth. A path model was used to examine the direct and indirect relationship of neighborhood constructs (safety, aesthetic quality, and walkability) on adult support for neighborhood youth. Neighborhood aesthetic quality and the walking environment were directly associated with adult support for youth, whereas perceived safety was indirectly associated. Collective efficacy partially explained these relationships. Findings support theorized relationships between people and places; improvements to neighborhood physical environment may directly impact resident adults’ perceptions of neighborhood young people.  相似文献   
440.
ABSTRACT— Childhood-onset antisocial behavior is an important predictor of chronic and serious forms of antisocial behavior in later life. Both biological and social factors are involved in the development of abnormal behavior. We examine the underlying role of stress-response systems in the link between early social adversity and juvenile antisocial behavior, and propose that children with genetically and/or perinatally based neurobiological deficits have problems in activating these systems and therefore experience difficulties in regulating affect and behavior. Underactivity or attenuated reactivity of the stress-response systems may predispose antisocial individuals to seek out stimulation or take risks, and thereby explain deficits in learning and socialization. Further investigations of neurobiological functioning in antisocial children might not only indicate which children are more likely to persist in behaving antisocially but also guide the development of new interventions.  相似文献   
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