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151.
介绍基于STMicro公司的最新一代单片式有线数字电视机顶盒芯片QAMi5516和嵌入式实时操作系统STLite/OS20设计的DVB-C数字电视机顶盒的总体方案,阐述DVB-C数字电视机顶盒的软硬件设计方法,给出DVB-C数字电视机顶盒的性能测试结果。 相似文献
152.
153.
聚(亚硅基二炔基蒽)(PSDEA)经实验测定具有空穴传输的能力. 为了模拟此高聚物的性质, 设计了一系列亚硅基二炔基蒽(SDEA)的寡聚物,利用密度泛函理论方法在B3LYP/6-31G(d)水平上对其构型进行优化. 寡聚物的能隙随着链长的增加而减少,同时蒽环上吸电基团的存在也使能隙减少. 在B3LYP/6-31G水平上计算寡聚物的13C化学位移以及蒽环中心位置的核独立化学位移. 寡聚物中与硝基相连的碳原子的化学位移与未连硝基的寡聚物中相同碳原子的化学位移相比向高场移动. 蒽环中心的芳香性在吸电子基团存在时减弱,但随着亚硅基数目的增加而增强. 用于核独立化学位移计算的最敏感区域是蒽环上方0.1 nm处. 相似文献
154.
Fluorescence correlation spectroscopy (FCS) data acquisition and analysis routines were developed and implemented in a home-built, multiparameter photon-counting microscope. Laser excitation conditions were investigated for two representative fluorescent probes, Rhodamine110 and enhanced green fluorescent protein (EGFP). Reliable local concentrations and diffusion constants were obtained by fitting measured FCS curves, provided that the excitation intensity did not exceed 20% of the saturation level for each fluorophore. Accurate results were obtained from FCS measurements for sample concentrations varying from pM to μM range, as well as for conditions of high background signals. These experimental constraints were found to be determined by characteristics of the detection system and by the saturation behavior of the fluorescent probes. These factors actually limit the average number of photons that can be collected from a single fluorophore passing through the detection volume. The versatility of our setup and the data analysis capabilities were tested by measuring the mobility of EGFP in the nucleus of Drosophila cells under conditions of high concentration and molecular crowding. As a bioanalytical application, we studied by FCS the binding affinity of a novel peptide-based drug to the cancer-regulating STAT3 protein and corroborated the results with fluorescence polarization analysis derived from the same photon data. 相似文献
155.
《Journal of Electrostatics》2014,72(3):198-202
The vast literature concerning circadian rhythm is devoted mostly to forces that influence operation and harmful effects resulting from disturbances to the clock. The present review presents a novel, unifying theme for influences from protein N-acetylation, phosphorylation and sulfation based on electrochemistry. The unifying theme entails formation of electrostatic fields in the various processes, namely from formation of amide from protein amine in acetylation, presence of phosphate anions from phosphorylation and sulfate anions from sulfation. The electrostatic fields may operate as bridges in communication or in energetics derived from phosphorylation. Other electrochemical and magnetic effects are presented. 相似文献
156.
Cell growth and replication occurs in an orderly manner through a set of tightly coordinated physiological events, classified as G0, G1, S, G2 and M in conformity to their characteristics. In a previous work, by combining the results of flow cytometry (FC) using propidium iodide (PI) staining, PI-FC, and Fourier Transform Infrared Microspectroscopy (FTIRM), we gathered information to classify live B16 cells into three different set of phases (G0/G1, S and G2/M), according to their nucleic acid content measured as the area integral of the Phosphate I band (PhI, 1274–1182 cm−1). In this work, we demonstrate that, once built a calibration dataset for a cell line determining the intervals of the PhI area integral related to each phase of the cell cycle, such data can be used for assigning the stage to which a live cell belongs without the support of FC. In addition, we evaluate the spectral profile of early G1 B16 cells, and compare it with the one of G0 and late G1 cell cycle phases. FTIRM highlights that G0 and G1 phases are a continuum, where the content of RNA of early G1 cells is in between G0 and late G1, and the overall nucleic acid content varies accordingly. In the paper, we also pinpoint the effects on synchronization protocols on cellular biochemistry, further strengthening the potentialities of a totally label-free methodology for cell sorting. Finally, we demonstrate that the general concept behind the proposed approach may be extended to other mammalian cell lines: human bone osteosarcoma (U2OS) cells were tested. 相似文献
157.
嵌入式操作系统内核的实现 总被引:3,自引:0,他引:3
本文了嵌入式多任务操作系统的内容核的实现方法。提出了嵌入式网络操作系统内核的实现方案,详细地阐述了系统进程的创建,删除和调度的算法及实现在MotorolaDragonBall68EZ328微处理器上实现了该内核并已运行了国家ASIC系统工程技术研究中心的PDA产品中。 相似文献