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81.
Longitudinal division of the corpus callosum was performed in six normal beagles to determine surgical morbidity. The corpus callosum was divided sagittally on the midline and the effect on neurological function was determined. Five of six dogs were clinically normal within 14 days or less after surgery. One dog had persistent but improving clinical signs consistent with a forebrain disturbance at 30 days after surgery. Overall, minimal morbidity and no mortality was associated with this surgical procedure. Further study is indicated to determine the efficacy of this surgical treatment for seizure control in dogs with idiopathic epilepsy.  相似文献   
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Hybrid materials were prepared incorporating silica networks by the sol–gel process into the poly(amide-b-polyether) block copolymer PEBAX®. PEBAX®/silica hybrids were characterized by transmission electron microscopy, atomic force microscopy, differential scanning calorimetry, and X-ray diffraction. The pervaporation of phenol from dilute aqueous solutions through hybrid membranes was investigated. Films prepared with lower silica contents showed better dispersed inorganic networks and were more selective in the pervaporation of phenol/water solutions. Films prepared with higher silica contents had a clear phase-separated morphology with lower performance in pervaporation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 178–185, 2001  相似文献   
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通过钢渣桩在湿陷性黄土中的静荷载试验、土压力测试等试验结果的基础上,对钢渣桩复合地基、桩间土和钢渣单桩的p-s曲线以及其各自的承载力和相应的沉降量进行了分析,探讨了附加应力沿深度变化规律;研究了桩间土承载力、桩土应力比和桩土荷载比的变化规律,对钢渣单桩和碎石桩以及钢渣桩复合地基和石灰粉煤灰桩复合地基等的承载力特性进行了对比分析;对单桩施工影响范围和施工时地基隆起量进行了观测。  相似文献   
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We conducted a meta-analysis of age differences in predecisional information search (N = 1,304) that suggests that aging is associated with a small but significant decrease in predecisional information search (Hedges's g = –0.30). In addition, we investigated the consequences of limited information search for decision quality in real-world consumer environments using simulation methods. Overall, the results suggest that the aging decision maker can afford to neglect information because this leads to small losses in decision quality. In other words, less may be enough for the aging consumer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Magnetic Resonance Materials in Physics, Biology and Medicine - Histogram-based metrics extracted from diffusion-tensor imaging (DTI) have been suggested as potential biomarkers for cerebral small...  相似文献   
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根据三相异步电动机的主要失效模型,利用概率分析和补充变量方法,求得了三相异步电动机的可靠性指标和运行的经济指标。  相似文献   
89.

Objective

Point spread function (PSF) mapping enables estimating the displacement fields required for distortion correction of echo planar images. Recently, a highly accelerated approach was introduced for estimating displacements from the phase slope of under-sampled PSF mapping data. Sampling schemes with varying spacing were proposed requiring stepwise phase unwrapping. To avoid unwrapping errors, an alternative approach applying the concept of finite rate of innovation to PSF mapping (FRIP) is introduced, using a pattern search strategy to locate the PSF peak, and the two methods are compared.

Materials and methods

Fully sampled PSF data was acquired in six subjects at 3.0 T, and distortion maps were estimated after retrospective under-sampling. The two methods were compared for both previously published and newly optimized sampling patterns. Prospectively under-sampled data were also acquired. Shift maps were estimated and deviations relative to the fully sampled reference map were calculated.

Results

The best performance was achieved when using FRIP with a previously proposed sampling scheme. The two methods were comparable for the remaining schemes. The displacement field errors tended to be lower as the number of samples or their spacing increased.

Conclusion

A robust method for estimating the position of the PSF peak has been introduced.
  相似文献   
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