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81.
A spray drying approach was used to apply 15-nm-thick SiO2 continuous coatings onto ZnS:Ag phosphor particles. A prehydrolyzed TEOS dip coating formula was used as the SiO2 precursor. The phosphor was mixed together with the precursor then atomized without allowing gelation to occur until the droplets containing the particles were in flight. The coating gelled and dried while falling through a graded heat zone. The dried coated particles were captured in a cyclone separator and heat-treated to further densify the SiO2 coating. The coatings protected the phosphors while in service in field emission display (FED) devices.  相似文献   
82.
Six synthetic heparin-like oligosaccharides have been used to investigate the effect of the oligosaccharide sulfation pattern on the stimulation of acidic fibroblast growth factor (FGF-1) induced mitogenesis signaling and the biological significance of FGF-1 trans dimerization in the FGF-1 activation process. It has been found that some molecules with a sulfation pattern that does not contain the internal trisaccharide motif, which has been proposed for high affinity for FGF-1, stimulate FGF-1 more efficiently than those with the structure of the regular region of heparin. In contrast to regular region oligosaccharides, in which the sulfate groups are distributed on both sides of their helical three-dimensional structures, the molecules containing this particular sulfation pattern display the sulfate groups only on one side of the helix. These results and the fact that these oligosaccharides do not promote FGF-1 dimerization according to sedimentation-equilibrium analysis, confirm the importance of negative-charge distribution in the activation process and strongly suggest that FGF dimerization is not a general and absolute requirement for biological activity.  相似文献   
83.
Data obtained from 102 skin lesions in vivo by spectroscopic oblique-incidence reflectometry were analyzed. The participating physicians initially divided the skin lesions into two visually distinguishable groups based on the lesions' melanocytic conditions. Group 1 consisted of the following two cancerous and benign subgroups: (1) basal cell carcinomas and squamous cell carcinomas and (2) benign actinic keratoses, seborrheic keratoses, and warts. Group 2 consisted of (1) dysplastic nevi and (2) benign common nevi. For each group, a bootstrap-based Bayes classifier was designed to separate the benign from the dysplastic or cancerous tissues. A genetic algorithm was then used to obtain the most effective combination of spatiospectral features for each classifier. The classifiers, tested with prospective blind studies, reached statistical accuracies of 100% and 95% for groups 1 and 2, respectively. Properties that related to cell-nuclear size, to the concentration of oxyhemoglobin, and to the concentration of deoxyhemoglobin as well as the derived concentration of total hemoglobin and oxygen saturation were defined to explain the origins of the classification outcomes.  相似文献   
84.
Federico A  Kaufmann GH 《Applied optics》2003,42(35):7066-7071
We evaluate the use of a smoothed space-frequency distribution (SSFD) to retrieve optical phase maps in digital speckle pattern interferometry (DSPI). The performance of this method is tested by use of computer-simulated DSPI fringes. Phase gradients are found along a pixel path from a single DSPI image, and the phase map is finally determined by integration. This technique does not need the application of a phase unwrapping algorithm or the introduction of carrier fringes in the interferometer. It is shown that a Wigner-Ville distribution with a smoothing Gaussian kernel gives more-accurate results than methods based on the continuous wavelet transform. We also discuss the influence of filtering on smoothing of the DSPI fringes and some additional limitations that emerge when this technique is applied. The performance of the SSFD method for processing experimental data is then illustrated.  相似文献   
85.
A planar photonic crystal that allows inherently gap-guided single-mode waveguides is proposed and discussed. This novel structure consists of a two-dimensional lattice of silicon rods embedded on a thin silica slab sandwiched between two silica claddings whose refractive indices are slightly lower than the index of the silica core. The physical parameters of the structure, i.e., rod radius and core thickness, are optimized to maximize the bandgap width for odd modes. Lossless guided modes inside the bandgap and below the claddings' light cone are obtained by reducing the radius of a row of rods. The waveguide bandwidth can be increased by inserting a thin silicon dielectric waveguide instead of the row of rods. The proposed approach may overcome many of the common drawbacks in conventional holes-on-dielectric planar photonic crystal waveguides.  相似文献   
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87.
Whereas biomedical products are required to be tested for safety with respect to vulnerable organ systems, psychosocial treatments are not required to be tested for safety with respect to vulnerable social systems such as the family. This article provides some evidence for the need to document the potential negative effects of psychosocial treatments on family-level outcomes. Three randomized controlled trials are reviewed in which independent ratings or self-reports of family functioning were measured. Each of the 3 studies compared the efficacy of a family and a nonfamily treatment. Totally unexpectedly, the nonfamily treatment in each of the 3 trials demonstrated significant declines in family functioning. The authors suggest that psychosocial treatments with vulnerable populations have the potential to produce negative side effects on families. Therefore, it is important to conduct further research to determine whether safety studies should be required for psychosocial treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
89.
Servet is a suite of benchmarks focused on extracting a set of parameters with high influence on the overall performance of multicore clusters. These parameters can be used to optimize the performance of parallel applications by adapting part of their behavior to the characteristics of the machine. Up to now the tool considered network bandwidth as constant and independent of the communication pattern. Nevertheless, the inter-node communication bandwidth decreases on modern large supercomputers depending on the number of cores per node that simultaneously access the network and on the distance between the communicating nodes. This paper describes two new benchmarks that improve Servet by characterizing the network performance degradation depending on these factors. This work also shows the experimental results of these benchmarks on a Cray XE6 supercomputer and some examples of how real parallel codes can be optimized by using the information about network degradation.  相似文献   
90.
This paper examines the problem of decoupling designs for linear multivariable systems. Both partial and diagonal decoupling designs are considered. The development is based on an algebraic approach and the use of coprime factorizations, which provide a mechanism to account for key system properties including internal stability and decoupling invariants. The results obtained include necessary and sufficient conditions for decoupling and a parametrization of all decoupling controllers.  相似文献   
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