50,179 research outputs found
Honokiol, a Neuroprotectant against Mouse Cerebral Ischaemia, Mediated by Preserving Na(+), K(+)-ATPase Activity and Mitochondrial Functions.
No full textClinical evaluation of allograft (DFDBA) and xenograft (Bi-Oss) combined with bioresorbable membrances in the treatment of intraosseous defects: Report of cased.
No full textIntravitreal triamcinolone staining observation of residual undetached cortical vitreous after posterior vitreous detachment.
No full textComparison of microdebrider-assisted inferior turbinoplasty and submucosal resection for children with hypertrrophic inferior turbinates
No full textAll-optical signal processing using cascaded quadratic interactions in periodically poled lithium niobate waveguides
No full textThis thesis investigates all-optical signal processing using cascaded quadratic nonlinearities in periodically poled lithium niobate (PPLN) waveguides for telecommunication applications. PPLN waveguides which possess high second-order nonlinearity are attractive due to their suitable properties with respect to high compactness, high operating speed and resistance to parasitic effects. They allow the implementation of various advanced signal processing functionalities which will be required in future ultrahigh speed fibre-optic communication systems. Several novel all-optical signal processing techniques relying on two types of cascaded quadratic processes in PPLN waveguides, namely cascaded second harmonic generation and difference frequency generation (cSHG/DFG) and cascaded sum frequency generation and difference frequency generation (cSFG/DFG), are demonstrated. These two processes are conventionally employed for wavelength conversion in the telecommunication band. To facilitate the use of these wavelength converters, a systematic study of the acceptance bandwidths of cSHG/DFG and cSFG/DFG in PPLN waveguides is presented. Following this study, an optical time- divisionmultiplexing to wavelength-division multiplexing format conversion scheme, which relies on the generation of linearly chirped pulses which are then optically switched with data pulses using cSHG/DFG in a PPLN waveguide, is demonstrated. Signal regeneration techniques exploiting cascaded quadratic nonlinearities in PPLN waveguides are also investigated. An all-optical signal retiming system for on-off keying signals relying on pulse shaping and cSHG/DFG-based switching in a PPLN waveguide is demonstrated. Subsequently, two novel configurations of PPLN-based phase sensitive amplifiers (PSA) which have the potential as regenerators for phase-shift keying signals are demonstrated. Finally, a novel method for the elimination of arbitrary frequency chirp from short optical pulses is presented. In addition, the thesis contains a study on the use of OFCGs as telecommunication sub-picosecond pulse sources. Both a theoretical and experimental study of the intensity and phase properties of the pulses generated by an OFCG is presented. Furthermore, two approaches are proposed to compensate for the intrinsic chirp of the OFCGs
Hypoxia-stimulated vascular endothelial growth factor production in human nasal polyp fibroblasts: effect of epigallocatechin-3-gallate on hypoxia-inducible factor-1 alpha synthesis
No full textTissue engineering bone formation in novel recombinant human bone morphogenic protein 2-atelocollagen composite scaffolds
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Liu shi gong hui zhua sheng chan cu ge ming
No full text《三忠于》红卫兵揪刘尖兵绘画.文字: 刘氏工会 抓生产促革命;下款: 《三忠于》红卫兵揪刘尖兵绘画 一九六七年二月十三日; 印記: 忠于毛主席 忠于毛泽东思想 忠于毛主席的革命路线.裝裱後高寬: 143 x 38 cm.Title devised by cataloguer."San zhong yu" hong wei bing jiu Liu jian bing hui hua.Wen zi : Liu shi gong hui zhua sheng chan cu ge ming; Xia kuan : "San zhong yu" hong wei bing jiu Liu jian bing hui hua 1967 nian 2 yue 13 ri; Yin ji : zhong yu Mao zhu xi zhong yu Mao Zedong si xiang zhong yu Mao zhu xi de ge ming lu xian.Zhuang biao hou gao kuan : 143 x 38 cm
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