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11.
A dichoptic masking procedure was used to test whether the mask-dependent cuing effects found in luminance detection by P. L. Smith (2000a) were due to integration masking or interruption masking. Attentional cuing enhanced detection sensitivity (d') when stimuli were backwardly masked with either dichoptic or monoptic masks, whereas no cuing effect was found with unmasked stimuli, implying the mask dependencies were due to interruption of stimulus processing in visual cortex by the mask. The effect is predicted by a gated diffusion process model in which masks interrupt stimulus processing and attention controls the flow of information to a sequential-sampling decision mechanism. The model correctly predicts different patterns of performance for detection and discrimination and cuing effects in simple reaction time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Crivelli S Byrd R Eskow E Schnabe R Yu R Philip TM Head-Gordon T 《Computers & chemistry》2000,24(3-4):489-497
We present a global optimization strategy that incorporates predicted restraints in both a local optimization context and as directives for global optimization approaches, to predict protein tertiary structure for alpha-helical proteins. Specifically, neural networks are used to predict the secondary structure of a protein, restraints are defined as manifestations of the network with a predicted secondary structure and the secondary structure is formed using local minimizations on a protein energy surface, in the presence of the restraints. Those residues predicted to be coil, by the network, define a conformational sub-space that is subject to optimization using a global approach known as stochastic perturbation that has been found to be effective for Lennard-Jones clusters and homo-polypeptides. Our energy surface is an all-atom 'gas phase' molecular mechanics force field, that is combined with a new solvation energy function that penalizes hydrophobic group exposure. This energy function gives the crystal structure of four different alpha-helical proteins as the lowest energy structure relative to other conformations, with correct secondary structure but incorrect tertiary structure. We demonstrate this global optimization strategy by determining the tertiary structure of the A-chain of the alpha-helical protein, uteroglobin and of a four-helix bundle, DNA binding protein. 相似文献
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Philip Dobie Julie Dendy Christine Sherman Jenny Padgham Anna Wood Angharad M. R. Gatehouse 《Journal of Stored Products Research》1990,26(4):177-186
The importance of carefully applied bioassay techniques is highlighted for identifying resistance of Phaseolus spp to the bruchids Acanthoscelides obtectus (Say) and Zabrotes subfasciatus Boheman. Two potential sources of resistance are identified amongst the varieties of P. vulgaris screened. In one the presence of a lectin-like protein (LLP) was identified, which has previously been associated with resistance, while in the other, resistance may be linked to the presence of a novel protein, similar to but not the same as LLP. The use of anti-LLP antibodies are suggested as a useful tool for distinguishing between resistant and susceptible varieties. Five varieties of P. lunatus and six of P. acutifolius are shown to be resistant to A. obtectus, and the potential is recognized for transferring resistant genes to P. vulgaris via interspecific crosses. 相似文献
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Flat vacuum glazings consisting of a narrow evacuated space between two glass panes separated by an array of small support pillars have been fabricated. A guarded hot box calorimeter was designed and constructed to measure their heat transfer coefficients. Experimental measurements of temperatures and rates of heat transfer were found to be in very good agreement with those predicted using a developed finite element model. A method for determining the heat transfer coefficient of the evacuated gap has been established and comparisons are made between the measured and predicted glass surface temperature profiles of the exposed glass area and the heat transfer coefficients of the total glazing system in order to validated the model. 相似文献
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Using a three-dimensional finite volume model, the thermal performance of an electrochromic vacuum glazing was simulated for insolation intensities between 0 and 1200 W m−2. The electrochromic evacuated glazing simulated consisted of three glass panes 0.5 m by 0.5 m with a 0.12 mm wide evacuated space between two 4 mm thick panes supported by 0.32 mm diameter pillars spaced on a 25 mm square grid contiguously sealed by a 6 mm wide metal edge seal. The third glass pane on which the electrochromic layer was deposited was assumed to be sealed to the evacuated glass unit. The simulations indicate that when facing the indoor environment, the temperature of the glass pane with the electrochromic layer can reach 129.5 °C for an incident insolation of 600 W m−2. At such temperatures unacceptable occupant comfort would ensue and the durability of the electrochromic glazing would be compromised. The glass pane with the electrochromic layer must therefore face the outdoor environment. 相似文献