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81.
This paper presents an analysis of some of the electromagnetic wave effects that occur when millimeter-wave beams are used for processing ceramic slabs and joints. These include interference effects on the couplings of the beam into a dielectric slab, guiding of the millimeter-wave beam through a ceramic joint, and standing-wave effects on the uniformity of energy deposition within the slab or joint. It also calculates the extent of the mitigation of the nonuniform energy deposition by thermal smoothing via heat conduction.  相似文献   
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The purpose of this study was to determine if asiatic acid may act efficiently in the model of cyclophosphamide (CYP)-induced cystitis in rats. We performed experiments after administration of CYP (single dose 200 mg/kg, intraperitoneally), asiatic acid (30 mg/kg/day for 14 consecutive days, by oral gavage), or CYP plus asiatic acid, during which conscious cystometry, measurements of urothelium thickness and bladder edema, as well as selected biomarkers analyses were conducted. In rats that received asiatic acid together with CYP, a drop in bladder basal pressure, detrusor overactivity index, non-voiding contraction amplitude, non-voiding contraction frequency, and the area under the pressure curve were observed, when compared to the CYP group. Furthermore, a significant increase in threshold pressure, voided volume, intercontraction interval, bladder compliance, and volume threshold to elicit NVC were found in that group accordingly. Administration of the asiatic acid successfully restored concentrations of biomarkers both in bladder urothelium (BDNF, CGRP, OCT-3, IL-1β, IL-6, NGF, nitrotyrosine, malondialdehyde, TNF-α, SV2A, SNAP23, SNAP25, PAC-1, ORM1, occludin, IGFBP-3, HB-EGF, T–H protein, Z01, and HPX) and detrusor muscle (Rho kinase and VAChT) in CYP-treated rats. Finally, asiatic acid significantly decreased urothelium thickness and bladder oedema. Asiatic acid proved to be a potent and effective drug in the rat model of CYP-induced cystitis.  相似文献   
83.
凤凰山地区岩心钻探施工技术探讨   总被引:2,自引:2,他引:0  
由于受构造的影响,凤凰山地区地层破碎强烈、结构松散且胶结性差,导致成孔、护壁难度较大.该区地层中存在多层厚度不等的硅质板岩和长石石英岩,硅质含量高,结构致密坚硬且研磨性弱,属于典型的坚硬“打滑”地层.同时,地层中还存在多层不稳定的碳质板岩,遇水松散,孔壁极不稳定,造成钻探施工难度大.通过多次的施工实践,采用套管护壁,合...  相似文献   
84.
棉田矿区位于吉林省东部,是以石英脉型和破碎蚀变带型为主的金矿床,区内矿产资源丰富,构造发育,为金矿富集提供了有利环境.通过总结该矿床的地质特征,分析矿床类型和成因,归纳出找矿标志,对矿区进行了成矿预测.在矿区开展了成矿预测研究,指出下一步找矿方向.  相似文献   
85.
We have synthesized segmented polyurethane (SPU)/silica nanoparticle (SiNP) nanocomposites with extraordinarily high tensile strength and strain-at-break using an in-situ polymerization method with low SiNP concentrations. A 20-fold increase in strain-at-break compared with the pristine polymer has been achieved for the 0.5 wt% SiNP nanocomposites. A suite of characterization tools including transmission electron microscopy, ultra-small angle X-ray scattering, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis has been used to correlate the phase morphology, crystallization, and mechanical properties. The location of SiNP in the phase separated SPU is believed to be the main reason for the mechanical property enhancement.  相似文献   
86.
To evaluate the functional neuroanatomies underlying letter and category fluency, 18 normal controls were studied with oxygen-15 water regional cerebral blood flow positron emission tomography. Three counterbalanced conditions each consisted of 6 trials (45 s each): letter fluency (generating words when cued with a particular letter), semantic fluency (generating words when cued with a particular category), and a control condition (generating days of the week and months of the year). Relative to the control, participants activated similar brain regions during both fluency tasks, including the anterior cingulate, left prefrontal regions, thalamus, and cerebellum; reductions were found in parietal and temporal regions. In a direct comparison of the 2 fluency tasks, inferior frontal cortex and temporoparietal cortex (hypothesized to participate in a phonologic loop for accessing word pronunciation) were activated more during letter than semantic fluency, whereas left temporal cortex (associated with access to semantic storage) was activated more during semantic than letter fluency. This study identifies subtle differences in the neural networks underlying letter and semantic fluency that may underlie the dissociation of these abilities in patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
In this editorial, the editor discusses the diversity of material in the current issue of Psychological Trauma: Theory, Research, Practice and Policy (PT: TRPP). He addresses questions that were raised by the pieces in this issue including ones as fundamental as what constitutes a psychological trauma. The editors believe that it is extremely important that as many facets of this terrain be examined and represented in the pages of PT: TRPP as possible. Only by continually and actively striving to maintain an inclusive perspective can we hope to work toward evolving a reasonable level of understanding of psychological trauma in all its richness and complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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