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61.
The cAMP/PKA pathway plays a critical role in learning and memory systems in animals ranging from mice to Drosophila to Aplysia. Studies of olfactory learning in Drosophila suggest that altered expression of either positive or negative regulators of the cAMP/PKA signaling pathway beyond a certain optimum range may be deleterious. Here we provide genetic evidence of the behavioral and physiological effects of increased signaling through the cAMP/PKA pathway in mice. We have generated transgenic mice in which the expression of a constitutively active form of Gsalpha (Gsalpha* Q227L), the G protein that stimulates adenylyl cyclase activity, is driven in neurons within the forebrain by the promoter from the CaMKIIalpha gene. Despite significantly increased adenylyl cyclase activity, Gsalpha* transgenic mice exhibit PKA-dependent decreases in levels of cAMP due to a compensatory up-regulation in phosphodiesterase activity. Interestingly, Gsalpha* transgenic mice also exhibit enhanced basal synaptic transmission. Consistent with a role for the cAMP/PKA pathway in learning and memory, Gsalpha* transgenic mice show impairments in spatial learning in the Morris water maze and in contextual and cued fear conditioning tasks. The learning deficits observed in these transgenic mice suggest that associative and spatial learning requires regulated Gsalpha protein signaling, much as does olfactory learning in Drosophila.  相似文献   
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In this article, we describe the Interval Manager (INTMAN) software system for collecting timesampled observational data and present a preliminary application comparing the program with a traditional paper-and-pencil method. INTMAN is a computer-assisted alternative to traditional paper-and-pencil methods for collecting fixed interval time-sampled observational data. The INTMAN data collection software runs on Pocket PC handheld computers and includes a desktop application for Microsoft Windows that is used for data analysis. Standard analysis options include modified frequencies, percent of intervals, conditional probabilities, and kappa agreement matrices and values. INTMAN and a standardized paper-and-pencil method were compared under identical conditions on five dimensions: setup time, duration of data entry, duration of interobserver agreement calculations, accuracy, and cost. Overall, the computer-assisted program was a more efficient and accurate data collection system for time-sampled data than the traditional method.  相似文献   
64.
Assessment of practical skills in physical education lessons have often been criticised as subjective. In this study three experienced judges' ratings poorly predicted the 116 students' scores on the French badminton short service test.  相似文献   
65.
We studied error monitoring in ADHD and control children in a task requiring inhibition of a motor response. The extent of slowing following successful (stopped) and failed (nonstopped) inhibition was compared across groups. We also measured the time required to inhibit a response (stop signal reaction time, SSRT). Compared to controls, ADHD participants slowed less following nonstopped responses. Slowing did not vary with comorbid reading, oppositional, conduct or anxiety disorder, sex or ADHD subtype. Slowing after nonstopped responses was marginally, although significantly correlated with total ADHD symptoms and with age. ADHD participants had significantly longer SSRT than controls, but SSRT was not significantly correlated with slowing. The apparent deficit in error monitoring in ADHD and its independence from the inhibition deficit observed in ADHD has implications for executive control models of ADHD, performance problems associated with the disorder and for component theories of executive control.  相似文献   
66.
Objectives: This study has three interrelated objectives: (1) to track the adjustment of children and adolescents with sickle cell disease (SCD) or cystic fibrosis (CF) and their mothers through a third assessment point 2 years after the initial assessment; (2) to determine whether the adaptational processes of the transactional stress and coping model associated with adjustment at the initial assessment continue to be associated with adjustment 2 years later; and (3) to determine whether the pattern of association of adaptational processes with adjustments differs by illness subgroup. Methods: The study samples included 59 children with CF and 50 children with SCD and their mothers. Measures were obtained on maternal adjustment and appraisals of daily and illness stress, coping methods, and family functioning. Child measures included child-reported and mother-reported child adjustment and child perceptions of self-worth and health locus of control and pain coping methods. Results: Consistency in adjustment classification was only 31–32% for child self-report, 66% for mother-reported child behavior problems, and 56–77% for mother self-reported adjustment for the CF and SCD groups, respectively. Support was provided for the association of adaptational processes with maternal adjustment and with the adjustment of children with SCD but not for children with CF. Conclusion: The stability of adjustment has implications for prevention and treatment intervention and subsequent research steps. Intervention efforts should be focused on the relatively small subgroups of children with chronic illnesses and their mothers with consistently poor adjustment.  相似文献   
67.
We have used a combined genetic and pharmacological approach to define the time course of the requirement for protein kinase A (PKA) and protein synthesis in long-term memory for contextual fear conditioning in mice. The time course of amnesia in transgenic mice that express R(AB) and have genetically reduced PKA activity in the hippocampus parallels that observed both in mice treated with inhibitors of PKA and mice treated with inhibitors of protein synthesis. This PKA- and protein synthesis-dependent memory develops between 1 hr and 3 hr after training. By injecting the protein synthesis inhibitor anisomycin or the PKA inhibitor Rp-cAMPs at various times after training, we find that depending on the nature of training, contextual memory has either one or two brief consolidation periods requiring synthesis of new proteins, and each of these also requires PKA. Weak training shows two time periods of sensitivity to inhibitors of protein synthesis and PKA, whereas stronger training exhibits only one. These studies underscore the parallel dependence of long-term contextual memory on protein synthesis and PKA and suggest that different training protocols may recruit a common signaling pathway in distinct ways.  相似文献   
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69.
This article examines the prospects for an authentic regional architecture in the light of alternative development paradigms. It is argued that the failure of orthodox development strategies and the domination of western culture, including architecture, over non-Western cultures, is due to fundamental imbalances between northern and southern economic structures. By contrast, ecodevelopment, appropriate technology and regional architecture all represent significant devolutionary movements toward a global “eco-culture.” A cultural typology placing eco-culture in historical perspective is outlined. It is concluded that, to be fully effective, changes in development patterns in the south have to be matched by equivalent cultural changes in the North.  相似文献   
70.
40 and 48 subjects participated in two separate experiments aimed at reproducing the subliminal psychodynamic activation (SPA) phenomenon and taking into account the major methodological critique by Fudin (1986, 1990). Subjects were first exposed either to a full or one of all possible partial symbiotic messages and then to their anagram equivalents. Confounding and irrelevant influences were controlled; the results indicate that only the full symbiotic message improved motor performance. This strongly suggests that subjects encode the meaning of the full message and supports an interpretation in terms of an alleviation of an internal symbiotic conflict leading to a state of calmness conducive to improved motor performance.  相似文献   
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