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21.
The nucleus accumbens (NAcc) has been shown to play a role in motor and spatial learning. Protein kinase C (PKC) has been implicated in the mechanisms of initiation and maintenance of long-term potentiation that is thought to be involved in the storage of long-term memory. In the present study, the importance of de novo synthesis of PKC-gamma within the NAcc in the acquisition and retention of spatial discrimination learning was assessed using an antisense knockdown approach. Separate groups of Long-Evans rats were exposed to acute microinfusions (6microg/microl) of PKC-gamma antisense oligodeoxynucleotide (AS-ODN), control oligodeoxynucleotide (C-ODN) or vehicle into the NAcc at 24 and 3h before each training session. Behavioral findings showed that the blockade of NAcc-PKC-gamma translation caused impairments in the early phase of learning and retention of spatial information. Biochemical experiments showed that PKC-gamma expression was reduced and Ca(2+)/phospholipid-dependent protein kinase C (PKC) activity was blocked significantly in the AS-ODN-treated rats in comparison with control rats. The present findings suggest that NAcc-PKC-gamma plays a role during the early acquisition of spatial learning. Also, retention test results suggest that NAcc-PKC-gamma may be working as an intermediate factor involved in the onset of molecular mechanisms necessary for spatial memory consolidation within the NAcc.  相似文献   
22.
Previous researchers have proposed that because of their slow muscle-response latencies, 1- to 2-year-old children are unable to control hip-dominant postural responses when responding to balance threats (G. McCollum & T. Leen, 1989). To test that proposition, the authors exposed 41 children to backward support-surface translations and recorded muscle activations and movement kinematics. Children between 10 months and 10 years of age stood on a platform that was unexpectedly moved. Passive hip-dominant responses were observed among the least experienced walkers. In contrast, older children produced an active response, signified by higher levels of abdominal and quadriceps muscle activity and accompanied by larger hip flexor torques. Greater success in withstanding large magnitudes of perturbations were associated with actively generated hip responses.  相似文献   
23.
We evaluated video modeling and reinforcement for teaching perspective-taking skills to 3 children with autism using a multiple baseline design. Video modeling and reinforcement were effective; however, only 2 children were able to pass an untrained task, indicating limited generalization. The findings suggest that video modeling may be an effective technology for teaching perspective taking if researchers can continue to develop strategies for enhancing the generalization of these new skills.  相似文献   
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This is the first study to examine whether high school students experiencing frequent bullying behaviors are at risk for later depression and suicidality. A total of 236 students who reported frequent bullying behavior without depression or suicidality during a suicide screening were interviewed 4 years later to reassess depression, suicidal ideation, attempts, substance problems, and functional impairment and were compared to at‐risk youth identified during the screen, including 96 youth who also experienced bullying behavior. Youth who only reported frequent bullying behaviors (as bullies, victims, or both) did not develop later depression or suicidality and continued to have fewer psychiatric problems than students identified as at‐risk for suicide. Students who experienced bullying behaviors and depression or suicidality were more impaired 4 years later than those who had only reported depression or suicidality. Thus, assessment of bullying behaviors in screening protocols is recommended.  相似文献   
26.
The purpose of this study was to examine the attitudes toward the use of telephone crisis services (hotlines) among 519 adolescents in 9th through 12th grade mandatory health courses in six high schools in New York State. Few adolescents (2.1%) used hotlines and negative attitudes were stronger toward hotlines than they were toward other formal sources of help. The most common reasons for hotline nonuse related to feelings of self-reliance and shame. Objections to hotlines were strongest among students most in need of help by virtue of impaired functioning or feelings of hopelessness. The results underscore needed outreach efforts to youth.  相似文献   
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Michel Foucault's ethics of embodiment, focusing upon care of the self, has motivated feminist scholars to pursue promising models of embodied resistance to disciplinary normalization. Cressida Heyes, in particular, has advocated that these projects adopt practices of “somaesthetics,” following a program of body consciousness developed by Richard Shusterman. In exploring Shusterman's somaesthetics proposal, I find that it does not account for the subjective challenges of resisting normalization. Based on narrative theories of subjectivity, the role narrative plays in normalization, and a commitment to developing concrete, feminist practices of embodied ethics, I develop a model of “narrative somaesthetics” based on an updated consciousness‐raising model that emphasizes group heterogeneity and narrative conflict that deals with these challenges. Through an analysis of interviews with self‐identified femme lesbians and a “female to femme” transition support group featured in the documentary film, FtF: Female to Femme, I argue that narrative somaesthetics enables the analytical, genealogical work required to identify and weaken normalization's constraints on embodied feminist ethics.  相似文献   
29.
We used the take‐the‐best heuristic to develop a model to forecast the popular two‐party vote shares in U.S. presidential elections. The model draws upon information about how voters expect the candidates to deal with the most important issue facing the country. We used cross‐validation to calculate a total of 1000 out‐of‐sample forecasts, one for each of the last 100 days of the ten U.S. presidential elections from 1972 to 2008. Ninety‐seven per cent of forecasts correctly predicted the winner of the popular vote. The model forecasts were competitive compared to forecasts from methods that incorporate substantially more information (e.g., econometric models and the Iowa Electronic Markets). The purpose of the model is to provide fast advice on which issues candidates should stress in their campaign. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
30.
Objective: The authors evaluated the time course of the treatment effect of Osmotic-Release Oral System methylphenidate (OROS(?) MPH) HCl (Concerta(?), Raritan, NJ) CII in children with ADHD. Method: Data were combined from two double-blind, randomized, placebo-controlled, cross-over, analog classroom studies in children (9-12 years) with ADHD. Participants received an individualized dose of placebo or OROS(?) MPH on two laboratory school days. Permanent Product Math Test and Swanson, Kotkin, Agler, M-Flynn, and Pelham scores were evaluated 0.5 hr before dosing and 1, 2, 4, 10, 11, and 12.5 hr post dose. Analysis used a repeated-measures mixed model. Results: Treatment effects were present at all postdose assessment points (p < .0001 for all comparisons, n = 139). Adverse events were similar to previous reports for OROS(?) MPH. Conclusion: A robust treatment effect occurred with OROS(?) MPH; onset was at 1 hr and persisted for at least 12.5 hr after dosing.  相似文献   
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