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排序方式: 共有259条查询结果,搜索用时 15 毫秒
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This study examines the development of children's ability to express emotions in their human figure drawing. Sixty children of 5, 8, and 11 years were asked to draw "a man," and then a "sad", "happy," "angry" and "surprised" man. Expressivity of the drawings was assessed by means of two procedures: a limited choice and a free labelling procedure. Emotionally expressive drawings were then evaluated in terms of the number and the type of graphic cues that were used to express emotion. It was found that children are able to depict happiness and sadness at 8, anger and surprise at 11. With age, children use increasingly numerous and complex graphic cues for each emotion (i.e., facial expression, body position, and contextual cues). Graphic cues for facial expression (e.g., concave mouth, curved eyebrows, wide opened eyes) share strong similarities with specific "action units" described by Ekman and Friesen (1978) in their Facial Action Coding System. Children's ability to depict emotion in their human figure drawing is discussed in relation to perceptual, conceptual, and graphic abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
On a consistent field transfer in non linear inelastic analysis and ultimate load computation 总被引:1,自引:1,他引:0
In this work we propose a field transfer operator for remeshing carried out in the course of incremental analysis of a non
linear inelastic behavior. The proposed procedure is geared towards the ultimate load computation of a complex structure,
where we choose the appropriate mesh grading for each different phase of computations, starting with a coarse mesh for the
initial linear response and going towards a more refined mesh for highly nonlinear inelastic response. The proposed projection
operator is developed on the basis of diffuse approximation method. The key feature of such an operator is to guarantee the
conservation of relevant mechanics quantities which ensures a superior performance of the proposed field transfer with respect
to the standard remeshing procedure. We present the illustrative results both for an isotropic damage model and standard plasticity
model, indicating very satisfying performance. 相似文献
24.
Charles-Henri Bruneau Emmanuel Creusé Delphine Depeyras Patrick Gilliéron Iraj Mortazavi 《Computers & Fluids》2010,39(10):1875-1892
Several active and passive control techniques are used to reduce the drag coefficient of the square back Ahmed body. The results are carefully analyzed and compared to each other. The final goal of this paper is to show that it is possible to couple passive and active control techniques to improve the flow control. In the present study, a drag reduction of 30% is achieved, almost corresponding to the goal of automotive industry. 相似文献
25.
Delphine Antoni Hélène Burckel Elodie Josset Georges Noel 《International journal of molecular sciences》2015,16(3):5517-5527
Cell culture is an important tool for biological research. Two-dimensional cell culture has been used for some time now, but growing cells in flat layers on plastic surfaces does not accurately model the in vivo state. As compared to the two-dimensional case, the three-dimensional (3D) cell culture allows biological cells to grow or interact with their surroundings in all three dimensions thanks to an artificial environment. Cells grown in a 3D model have proven to be more physiologically relevant and showed improvements in several studies of biological mechanisms like: cell number monitoring, viability, morphology, proliferation, differentiation, response to stimuli, migration and invasion of tumor cells into surrounding tissues, angiogenesis stimulation and immune system evasion, drug metabolism, gene expression and protein synthesis, general cell function and in vivo relevance. 3D culture models succeed thanks to technological advances, including materials science, cell biology and bioreactor design. 相似文献
26.
Effects of caffeine on lipoprotein lipase gene expression during the adipocyte differentiation process 总被引:1,自引:0,他引:1
Cyril Couturier Brigitte Janyier Delphine Girlich Gilbert Béréziat Marise Andréani-Mangeney 《Lipids》1998,33(5):455-460
In this study, the effects of caffeine on lipoprotein lipase (LPL) gene expression were investigated in the 3T3-F442A preadipocyte
cell line during the adipocyte differentiation process by determining LPL enzymatic activity and its messenger RNA (mRNA)
level. The results demonstrate that caffeine acts on the gene expression of LPL, an early marker of adipocyte differentiation.
It has a biphasic action: it increases gene expression in terms of mRNA when it is added to preadipocytes during the early
stage of differentiation, but this is accompanied by a reduction of enzymatic activity. On the other hand, when caffeine is
added for long periods during differentiation and/or when it is added to mature adipocytes, it induces marked inhibition of
mRNA levels, correlated with a marked reduction of secreted enzymatic activity. The inhibitory effect of caffeine on LPL mRNA
level can be reproduced by theophylline, a phosphodiesterase inhibitor, and by dibutyryl cyclic AMP, a non-metabolizable analog
of cyclic AMP. However, the effect of caffeine and theophylline lasts longer than that of cyclic AMP, suggesting that a mechanism
other than inhibition of cyclic AMP hydrolysis may be involved in the action of caffeine. 相似文献
27.
Jean Lessard Jean-François Morin Jean-François Wehrung Delphine Magnin Esteban Chornet 《Topics in Catalysis》2010,53(15-18):1231-1234
Xylose was dehydrated over (H+) mordenite, using a continuous two-liquid-phase (aqueous-toluene) plug-flow reactor at 260 °C and 55 atm, with 98% conversion rate, 98% furfural molar yield, and 98% furfural selectivity (results from the first pass). Furfural in toluene was hydrogenated over a Cu/Fe catalyst, at 252 °C (gas-phase), in a 99% conversion rate to give 2-methylfuran in a 98% yield (same activity maintained for a 20-h operation). 相似文献
28.
Amélie Demoulin Delphine Neff Philippe Dillmann Valérie L’Hostis 《Corrosion Science》2010,52(10):3168-3179
Corrosion patterns on samples taken on binder and rebars from two buildings, respectively, aged of 46 and 260 years old have been characterised by coupling different analytical methods at microscopic scale. Different corrosion patterns have been observed. The first one is constituted by the initial mill scale made of wustite, magnetite and hematite. The second one contains remains of this mill scale embedded in phases formed after aqueous corrosion: oxyhydroxides as goethite or lepidocrocite containing marblings of ferrihydrite, maghemite and magnetite. On the thicker and older layers, marblings were only constituted of magnetite and maghemite. It is proposed that the structural evolution of the pattern and their marbling is linked to wet/dry cycles and/or pH condition evolution during the corrosion processes. 相似文献
29.
Geiser Christian; Eid Michael; Nussbeck Fridtjof W.; Courvoisier Delphine S.; Cole David A. 《Canadian Metallurgical Quarterly》2010,46(1):29
The authors show how structural equation modeling can be applied to analyze change in longitudinal multitrait-multimethod (MTMM) studies. For this purpose, an extension of latent difference models (McArdle, 1988; Steyer, Eid, & Schwenkmezger, 1997) to multiple constructs and multiple methods is presented. The model allows investigators to separate true change from measurement error and to analyze change simultaneously for different methods. The authors also show how Campbell and Fiske’s (1959) guidelines for analyzing convergent and discriminant validity can be applied to the measurement of latent change. The practical application of the multimethod change model is illustrated in a reanalysis of child depression and anxiety scores (N = 906 American children) that were assessed by self- and parent reports on three measurement occasions. The analyses revealed that (a) the convergent validity of change was low for both constructs and (b) sex was a significant predictor of self-reported, but not of parent reported, anxiety states. Finally, the authors discuss advantages and limitations and compare the model with other approaches for analyzing longitudinal MTMM data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Courvoisier Delphine S.; Eid Michael; Nussbeck Fridtjof W. 《Canadian Metallurgical Quarterly》2007,12(1):80
Extensions of latent state-trait models for continuous observed variables to mixture latent state-trait models with and without covariates of change are presented that can separate individuals differing in their occasion-specific variability. An empirical application to the repeated measurement of mood states (N = 501) revealed that a model with 2 latent classes fits the data well. The larger class (76%) consists of individuals whose mood is highly variable, whose general well-being is comparatively lower, and whose mood variability is influenced by daily hassles and uplifts. The smaller class (24%) represents individuals who are rather stable and happier and whose mood is influenced only by daily uplifts but not by daily hassles. A simulation study on the model without covariates with 5 sets of sample sizes and 5 sets of number of occasions revealed that the appropriateness of the parameter estimates of this model depends on number of observations (the higher the better) and number of occasions (the higher the better). Another simulation study estimated Type I and II errors of the Lo-Mendell-Rubin test. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献