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31.
Philippot Pierre; Schaefer Alexandre; Herbette Gwénola 《Canadian Metallurgical Quarterly》2003,3(3):270
The relation between emotion intensity and the voluntary activation of personal memories was investigated in 2 experiments. Two hypotheses were compared: the specificity hypothesis, which states that emotion intensity is positively related to the specificity of personal memories, and the strategic inhibition hypothesis, which postulates that specifying past experiences requires the inhibition of emotion. Study 1 showed that priming a specific (vs. overgeneral) access mode to autobiographical memory results in less emotion during a subsequent mental imagery trial. Study 2 replicated Study 1 with a wider array of emotions and a different method of emotion induction (films). Overall, results support the strategic inhibition hypothesis. The notion of specificity is discussed as well as implications for cognitive theories of emotion and their clinical applications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Using a scanning near-field optical microscope, we visualize, in three dimensions, the electromagnetic field distribution near an isolated slit aperture in a thin gold film. At the metal-air interface and for a TM incident polarization, we confirm some recently observed results and show that the slit generates two kinds of surface waves: a slowly decaying surface plasmon polariton and a quasi-cylindrical wave that decreases more rapidly when moving away from the slit. These waves are not generated for a TE incident polarization. In a noncontact mode, we also observe how the transmitted light diverges in free space. At a small distance from the slit (< 2 microm), we find that the emerging light spreads in all directions for TM, forming an electromagnetic cloud, whereas it is concentrated above the slit for TE, forming a more directive light jet. The experimental images are in good agreement with the numerical simulations. 相似文献
33.
Zagré NM Desplats G Adou P Mamadoultaibou A Aguayo VM 《Food and nutrition bulletin》2007,28(3):317-327
BACKGROUND: Micronutrient deficiencies during pregnancy are associated with adverse pregnancy outcomes, including reduced birthweight. Low birthweight is associated with increased risk of infant mortality and growth failure. OBJECTIVES: To assess the effects of prenatal supplementation with UNIMMAP (United Nations International Multiple Micronutrient Preparation) compared with iron/folic acid on average birthweight and incidence of low birthweight. METHODS: Pregnant women from 78 villages in Niger were included in a cluster-randomized, double-blinded, controlled supplementation trial. Baseline, monthly follow-up, and birth data were collected. Cluster analysis was conducted to assess differences in mean birthweight and incidence of low birthweight between groups using multiple linear regression models. Analyses were stratified by nutrition status and duration of supplementation. RESULTS: Of the 3,670 women recruited, 2,550 completed the study and provided complete birthweight data (1,328 received multiple micronutrients and 1,222 received iron/folic acid). Mean birthweight was significantly higher (67 g, p < .001) with multiple micronutrients (3,092 +/- 190 g) than with iron/folic acid (3,025 +/- 205 g); this corresponded to a 14% fall in the incidence of low birthweight (from 8.4% with multiple micronutrients to 7.2% with folic acid fortification). The impact of multiple micronutrients was greater when the supplements were taken for more than 150 days. The incidence of low birthweight was further reduced in women who entered pregnancy with a poorer nutrition status. CONCLUSIONS: Prenatal supplementation with multiple micronutrients had a greater positive impact on birthweight than supplementation with iron/folic acid. Our data suggest that prenatal supplementation with multiple micronutrients as part of a prenatal care package in addition to interventions to promote improved maternal prepregnancy nutrition status is an important strategy to increase birthweight and reduce the incidence of low birthweight. 相似文献
34.
Comparison of surface-enhanced resonance Raman scattering and fluorescence for detection of a labeled antibody 总被引:2,自引:0,他引:2
A comparison is made of the quantitative detection of a labeled antibody by surface-enhanced resonance Raman scattering (SERRS) and by fluorescence using the same instrument with the same laser excitation source. The area under the curve for the fluorescence band is greater than for any single peak in the SERRS spectrum, but the broad fluorescence band is more difficult to discriminate from the background at low concentrations. Using the peak height of one SERRS band and the peak height at the fluorescence maximum, the detection limit for SERRS was lower (1.19 x 10-11 mol.dm-3) than that obtained using fluorescence (3.46 x 10-10 mol.dm-3). The SERRS detection limit is calculated for the concentration of the sample added, but compared to fluorescence, there is an additional dilution step due to the addition of the colloid and the extent of this dilution is dependent on assay format. For comparison with the detection limits found earlier with labeled oligonucleotides, SERRS was remeasured with a 10 s accumulation time, and the final concentration in the cuvette after colloid addition and before any adsorption to the silver was used to calculate a detection limit of 2.79 x 10-13 mol.dm-3. This is comparable to the detection limit found using a similar SERRS procedure for an oligonucleotide labeled with the same dye. This experiment is dependent on many parameters that could affect this result, including the nature of the SERRS substrate, the excitation wavelength, and the dye chosen. However, the result indicates that SERRS can give assay sensitivities comparable or better than fluorescence for quantitative direct assay determination, suggesting that the much greater potential for multiple analyte detection could be exploited. 相似文献
35.
Quellec G Lamard M Cazuguel G Cochener B Roux C 《IEEE transactions on image processing》2012,21(4):1613-1623
Adaptive wavelet-based image characterizations have been proposed in previous works for content-based image retrieval (CBIR) applications. In these applications, the same wavelet basis was used to characterize each query image: This wavelet basis was tuned to maximize the retrieval performance in a training data set. We take it one step further in this paper: A different wavelet basis is used to characterize each query image. A regression function, which is tuned to maximize the retrieval performance in the training data set, is used to estimate the best wavelet filter, i.e., in terms of expected retrieval performance, for each query image. A simple image characterization, which is based on the standardized moments of the wavelet coefficient distributions, is presented. An algorithm is proposed to compute this image characterization almost instantly for every possible separable or nonseparable wavelet filter. Therefore, using a different wavelet basis for each query image does not considerably increase computation times. On the other hand, significant retrieval performance increases were obtained in a medical image data set, a texture data set, a face recognition data set, and an object picture data set. This additional flexibility in wavelet adaptation paves the way to relevance feedback on image characterization itself and not simply on the way image characterizations are combined. 相似文献