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Antkowiak A Audoly B Josserand C Neukirch S Rivetti M 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(26):10400-10404
A drop impacting a target cutout in a thin polymer film is wrapped by the film in a dynamic sequence involving both capillary forces and inertia. Different 3D structures can be produced from a given target by slightly varying the impact parameters. A simplified model for a nonlinear dynamic Elastica coupled with a drop successfully explains this shape selection and yields detailed quantitative agreement with experiments. This first venture into the largely unexplored dynamics of elastocapillary assemblies opens up the perspective of mass production of 3D packages with individual shape selection. 相似文献
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During concentration tasks, spontaneous attention shifts occurs towards self-centered matters. Little is known about the brain oscillatory activity underlying these mental phenomena. We recorded 128-channels electroencephalographic activity from 12 subjects performing a breath-counting task. Subjects were instructed to press a button whenever, based on their introspective experience, they realized their attention had drifted away from the task. Theta (4-7 Hz) and delta (2-3.5 Hz) EEG activity increased during mind wandering whereas alpha (9-11 Hz) and beta (15-30 Hz) decreased. A passive auditory oddball protocol was presented to the subjects to test brain-evoked responses to perceptual stimuli during mind wandering. Mismatch negativity evoked at 100 ms after oddball stimuli onset decreased during mind wandering whereas the brain-evoked responses at 200 ms after stimuli onset increased. Spectral analyses and evoked related potential results suggest decreased alertness and sensory processing during mind wandering. To our knowledge, our experiment is one of the first neuro-imaging studies that relies purely on subjects' introspective judgment, and shows that such judgment may be used to contrast different brain activity patterns. 相似文献
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Alessandrin A 《Soins. Psychiatrie》2012,(280):37-38
Sex reassignment protocols in France do not meet the demands of people in transition. Consequently, transsexual people draw up what are called "free" transitions, without any psychiatric follow-up, opening the way for discussion on the place of the law and the need for psychiatry in these cases. 相似文献
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El Ghazi F Desfeux A Brasse-Lagnel C Roux C Lesueur C Mazur D Remy-Jouet I Richard V Jégou S Laudenbach V Marret S Bekri S Prevot V Gonzalez BJ 《Neurobiology of disease》2012,45(3):871-886
In industrialized countries, cerebral palsy affects 2.5‰ of preterm and term infants. At a neurochemical level, the massive release of glutamate constitutes a major process leading to excitotoxicity and neonatal brain lesions. Previous studies, conducted in the laboratory, revealed that, in (δ/δ)VEGF(A) transgenic mice, glutamate-induced brain lesions are exacerbated suggesting that VEGF(A) could play a protective action against excitotoxicity. Using a model of cultured cortical brain slices, the aim of the study was to characterize the central effects of VEGF against glutamate-induced excitotoxicity in neonates. Exposure of brain slices to glutamate induced a strong increase of necrotic cell death in the deep cortical layer VI and a decrease of apoptotic death in superficial layers II-IV. When administered alone, a 6-h treatment with VEGF(A) had no effect on both apoptotic and necrotic deaths. In contrast, VEGF(A) abolished the glutamate-induced necrosis observed in layer VI. While MEK and PI3-K inhibitors had no effect on the protective action of VEGF(A), L-NAME, a pan inhibitor of NOS, abrogated the effect of VEGF(A) and exacerbated the excitotoxic action of glutamate. Calcimetry experiments performed on brain slices revealed that VEGF(A) reduced the massive calcium influx induced by glutamate in layer VI and this effect was blocked by L-NAME. Neuroprotective effect of VEGF(A) was also blocked by LNIO and NPLA, two inhibitors of constitutive NOS, while AGH, an iNOS inhibitor, had no effect. Nitrite measurements, electron paramagnetic resonance spectroscopy and immunohistochemistry indicated that glutamate was a potent inducer of NO production via activation of nNOS in the cortical layer VI. In vivo administration of nNOS siRNA promoted excitotoxicity and mimicked the effects of L-NAME, LNIO and NPLA. A short-term glutamate treatment increased nNOS Ser1412 phosphorylation, while a long-term exposure inhibited nNOS/NR2B protein-protein interactions. Altogether, these findings indicate that, in deep cortical layers of mice neonates, glutamate stimulates nNOS activity. Contrasting with mature brain, NO production induced by high concentrations of glutamate is neuroprotective and is required for the anti-necrotic effect of VEGF(A). 相似文献
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Guyard A Michelsen SI Arnaud C Lyons A Cans C Fauconnier J 《Research in developmental disabilities》2012,33(5):1594-1604
Living with a child with a disability can affect family life in various domains. Impacts on time, expenses, work, relationships within the family, social relationships and physical and psychological health can be observed. The Family Impact of Childhood Disability (FICD) is a specific instrument designed to assess this situation. Used in a cross-sectional survey, this questionnaire was extended to consider two missing aspects: impact on work and health (FICD+4). This paper addresses the psychometric qualities of the FICD in Europe among parents living with an adolescent with cerebral palsy. Expecting the FICD+4 could assess detailed impact dimensions, an exploratory analysis was conducted. We interviewed 242 families of 13- to 17-year-old adolescents with cerebral palsy living in Europe. Good psychometric properties were found in negative and positive FICD scales and in six underlying factors extracted from exploratory factor analysis on FICD+4. These results support the psychometric validity of the FICD in the assessment of the impact of disability in European families who live with an adolescent with cerebral palsy. They also highlight the multifaceted aspects of the impact of childhood disability on the family and suggest that the FICD+4 is a good tool for assessing specific negative impacts on time, finances, work, social relationships and positive impacts on parental feeling and family attitude. This scale needs further validation and could be helpful for research and clinical interventions. 相似文献