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951.
为消除全局干涉,提出了一种基于K-D树及刀具离散的高效刀轴矢量调整算法.算法首先以有限个点离散表示刀具,然后利用K-D树快速查找刀具的可能干涉点,并在此基础上计算调整后的刀轴矢量.为避免过大的刀轴矢量突变,提出一种分角度区域方法优化刀轴矢量.实例验证表明:算法能够高效实现全局干涉避免及刀轴矢量优化. 相似文献
952.
This paper presents a new method for image separation through employing a combined dictionary consisting of wavelets and complex shearlets. Because the combined dictionary sparsely represents points and curvilinear singularities respectively, the image can be decomposed into pointlike and curvelike parts as accurate as possible. The proposed method based on the geo- metric separation theory introduced by Donoho in 2005 shows that accurate geometric separation of the morphologically distinct fea- tures of points and curves can be achieved by l1 minimization. The experimental results show that the proposed method can not only be effective but also greatly reduce the computing time. 相似文献
953.
杨晓培 《江西科技师范学院学报》2014,(5):66-70
经济犯罪的概念虽被提出和使用很久,但至今仍未统一定论。我国的刑事政策决定了经济犯罪的客体,经济犯罪主要侵犯的客体是国家整体经济的秩序。本文在对域内外经济犯罪概念进行的聚讼与争鸣分析后,认为经济犯罪是指从事经济活动的自然人和法人在经济运行过程中,实施违反经济法规,侵害经济管理秩序和经济协调关系,情节严重,依法应当承担刑事责任的行为。经济犯罪概念的认定与特征的"限制"性释义取得规范,不仅易于了解经济犯罪的特殊性,也可使刑法的效能得到最大发挥。 相似文献
954.
Parvin Abraham Tessy Thomas Maliekal 《Cellular and molecular life sciences : CMLS》2017,74(7):1177-1189
Research of the past two decades has proved the relevance of single cell biology in basic research and translational medicine. Successful detection and isolation of specific subsets is the key to understand their functional heterogeneity. Antibodies are conventionally used for this purpose, but their relevance in certain contexts is limited. In this review, we discuss some of these contexts, posing bottle neck for different fields of biology including biomedical research. With the advancement of chemistry, several methods have been introduced to overcome these problems. Even though microfluidics and microraft array are newer techniques exploited for single cell biology, fluorescence-activated cell sorting (FACS) remains the gold standard technique for isolation of cells for many biomedical applications, like stem cell therapy. Here, we present a comprehensive and comparative account of some of the probes that are useful in FACS. Further, we illustrate how these techniques could be applied in biomedical research. It is postulated that intracellular molecular markers like nucleostemin (GNL3), alkaline phosphatase (ALPL) and HIRA can be used for improving the outcome of cardiac as well as bone regeneration. Another field that could utilize intracellular markers is diagnostics, and we propose the use of specific peptide nucleic acid probes (PNPs) against certain miRNAs for cancer surgical margin prediction. The newer techniques for single cell biology, based on intracellular molecules, will immensely enhance the repertoire of possible markers for the isolation of cell types useful in biomedical research. 相似文献
955.
Yue Shi Guang Yang Jia Yu Lina Yu Ruth Westenbroek William A. Catterall Lisa Juntti-Berggren Per-Olof Berggren Shao-Nian Yang 《Cellular and molecular life sciences : CMLS》2014,71(7):1289-1303
Apolipoprotein CIII (ApoCIII) not only serves as an inhibitor of triglyceride hydrolysis but also participates in diabetes-related pathological events such as hyperactivation of voltage-gated Ca2+ (CaV) channels in the pancreatic β cell. However, nothing is known about the molecular mechanisms whereby ApoCIII hyperactivates β cell CaV channels. We now demonstrate that ApoCIII increased CaV1 channel open probability and density. ApoCIII enhanced whole-cell Ca2+ currents and the CaV1 channel blocker nimodipine completely abrogated this enhancement. The effect of ApoCIII was not influenced by individual inhibition of PKA, PKC, or Src. However, combined inhibition of PKA, PKC, and Src counteracted the effect of ApoCIII, similar results obtained by coinhibition of PKA and Src. Moreover, knockdown of β1 integrin or scavenger receptor class B type I (SR-BI) prevented ApoCIII from hyperactivating β cell CaV channels. These data reveal that ApoCIII hyperactivates β cell CaV1 channels through SR-BI/β1 integrin-dependent coactivation of PKA and Src. 相似文献
956.
李阳 《科技情报开发与经济》2014,(11):31-32
随着现代科学技术的迅猛发展及数字信息资源的迅速增长,学科馆员服务也需要进一步深化。从服务理念、服务模式、服务内容3方面描述了学科馆员服务的正确定位,并对深化发展高校图书馆学科馆员服务提出了几点对策。 相似文献
957.
958.
959.
Miguel Bernabé-Rubio Miguel A. Alonso 《Cellular and molecular life sciences : CMLS》2017,74(22):4077-4095
Primary cilia are solitary, microtubule-based protrusions of the cell surface that play fundamental roles as photosensors, mechanosensors and biochemical sensors. Primary cilia dysfunction results in a long list of developmental and degenerative disorders that combine to give rise to a large spectrum of human diseases affecting almost any major body organ. Depending on the cell type, primary ciliogenesis is initiated intracellularly, as in fibroblasts, or at the cell surface, as in renal polarized epithelial cells. In this review, we have focused on the routes of primary ciliogenesis placing particular emphasis on the recently described pathway in renal polarized epithelial cells by which the midbody remnant resulting from a previous cell division event enables the centrosome for initiation of primary cilium assembly. The protein machinery implicated in primary cilium formation in epithelial cells, including the machinery best known for its involvement in establishing cell polarity and polarized membrane trafficking, is also discussed. 相似文献
960.
This paper considers the parameter estimation and stabilization of an unstable one-dimensional wave equation with matched general harmonic disturbance at the controlled end. The backstepping method for infinite-dimensional system is adopted in the design of the adaptive regulator. It is shown that the resulting closed-loop system is asymptotically stable. Meanwhile, the estimated parameter is shown to be convergent to the unknown parameter as time goes to infinity. 相似文献