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911.
Cancer diagnosis and treatment are of great interest due to the high death rate of cancer.To improve the cure rates of cancer,a diagnostic tool which can detect and treat cancer at initial stages is great needed.Laser-induced fluorescence(LIF) is an adequate analytical technique with advantages of high sensitivity,low sample consumption,short testing time,and suitable for in situ testing.Therefore,it has become one of the most widely used spectroscopic methods for cancer in vivo diagnosis in recent years.This review mainly focuses on the applications of in vivo LIF to distinguish premalignant,malignant from normal tissues in a variety of organ systems,such as lung breast,colon,cervix,esophagus,and bronchus.The potential influence factors for cancer diagnostics and the subsequent suitability of the method to different applications are well discussed.Meanwhile,the technical merits and weaknesses of the LIF technology for cancer diagnosis are also evaluated.Furthermore,different exogenous fluorophores,endogenous fluorophores,and fluorophores synthesized in the tissue are compared on their active principle and effect contrast.The technical potentials of LIF for further development and future applications are also presented as well in this review. 相似文献
912.
The demanganization reaction kinetics of carbon-saturated liquid iron with an eight-component slag consisting of CaO–SiO_2–MgO–FeO–MnO–Al_2O_3–TiO_2–CaF_2 was investigated at 1553, 1623, and 1673 K in this study. The rate-controlling step(RCS) for the demanganization reaction with regard to the hot metal pretreatment conditions was studied via kinetics analysis based on the fundamental equation of heterogeneous reaction kinetics. From the temperature dependence of the mass transfer coefficient of a transition-metal oxide(Mn O), the apparent activation energy of the demanganization reaction was estimated to be 189.46 k J·mol~(–1) in the current study, which indicated that the mass transfer of Mn O in the molten slag controlled the overall rate of the demanganization reaction. The calculated apparent activation energy was slightly lower than the values reported in the literature for mass transfer in a slag phase. This difference was attributed to an increase in the "specific reaction interface"(SRI) value, either as a result of turbulence at the reaction interface or a decrease of the absolute amount of slag phase during sampling, and to the addition of calcium fluoride to the slag. 相似文献
913.
The wide acceptance and data deluge in medical imaging processing require faster and more efficient systems to be built.Due to the advances in heterogeneous architectures recently,there has been a resurgence in the first research aimed at FPGA-based as well as GPGPU-based accelerator design.This paper quantitatively analyzes the workload,computational intensity and memory performance of a single-particle 3D reconstruction application,called EMAN,and parallelizes it on CU-DA GPGPU architectures and decouples the memory operations from the computing flow and orches-trates the thread-data mapping to reduce the overhead of off-chip memory operations.Then it exploits the trend towards FPGA-based accelerator design,which is achieved by offloading computingintensive kernels to dedicated hardware modules.Furthermore,a customized memory subsystem is also designed to facilitate the decoupling and optimization of computing dominated data access patterns.This paper evaluates the proposed accelerator design strategies by comparing it with a parallelized program on a 4-cores CPU.The CUDA version on a GTX480 shows a speedup of about 6 times.The performance of the stream architecture implemented on a Xilinx Virtex LX330 FPGA is justified by the reported speedup of 2.54 times.Meanwhile,measured in terms of power efficiency,the FPGA-based accelerator outperforms a 4-cores CPU and a GTX480 by 7.3 times and 3.4 times,respectively. 相似文献
914.
Lian Duan 《系统科学与复杂性》2018,31(3):608-620
This paper studies a class of general BAM neural networks with multiple delays. Employing the exponential dichotomy theory and fixed point method, together with constructing suitable Lyapunov functionals, easily verifiable delay-independent criteria are established to ensure the existence and global exponential stability of pseudo almost periodic solutions, which not only generalize but also complement some existing ones. These theoretical results are also supported with numerical simulations. 相似文献
915.
文章简要介绍了会计电算化的发展历程及其在现代企业管理中的重要作用以及对企业内部控制方面的重要影响,分析了当前会计电算化与传统会计系统相比所存在的一系列问题,并相应提出了企业加强会计电算化内部控制的部分措施. 相似文献
916.
文章通过对个体的价值取向、期望值,社会比较及社会环境对个体主观幸福感的影响,来分析和说明个体如何正确看待和提高主观幸福感。 相似文献
917.
我国工程伦理教育在价值标准上的模糊性是阻碍它进一步发展的重要原因。工程伦理教育的价值谱系由自然伦理、商谈伦理和责任伦理构成,其确立的依据主要是当今工程活动中的实践伦理和价值关系。自然伦理主要涉及的是人与自然的关系问题,商谈伦理主要涉及的是人与人的关系问题,责任伦理主要涉及的是人与社会和个体与自我的关系问题。 相似文献
918.
Coverage of communication-based sensor nodes deployed location and energy efficient clustering algorithm in WSN
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An effective algorithm based on signal coverage of effective communication and local energy-consumption saving strategy is proposed for the application in wireless sensor networks. This algorithm consists of two sub algorithms. One is the multi-hop partition subspaces clustering algorithm for ensuring local energybalanced consumption ascribed to the deployment from another algorithm of distributed locating deployment based on efficient communication coverage probability (DLD-ECCP). DLD-ECCP makes use of the characteristics of Markov chain and probabilistic optimization to obtain the optimum topology and number of sensor nodes. Through simulation, the relative data demonstrate the advantages of the proposed approaches on saving hardware resources and energy consumption of networks. 相似文献
919.
Fine mapping of cisc(t), a gene for cold-induced seedling chlorosis, and identification of its candidate in rice 总被引:1,自引:0,他引:1
Tao Lan Bin Wang QiuPing Ling ChunHua Xu ZhiJun Tong KangJing Liang YuanLin Duan Jing Jin WeiRen Wu 《科学通报(英文版)》2010,55(27-28):3149-3153
The seedlings of indica rice cultivar Dular are susceptible to chlorosis under low temperature conditions. Our previous studies indicated that low temperature-induced seedling chlorosis is controlled by a recessive gene, located between SSR markers RM257 and RM242, on the long arm of chromosome 9. We temporarily named the gene cisc(t). Using a large F2 population derived from a cross between Dular and the japonica cultivar Lemont, which displays a normal green color at low temperatures, cisc(t) was fine mapped to within a 12-kb interval. There is only one annotated gene in this interval, which encodes a pentatricopeptide repeat (PPR) protein. Sequence analysis indicated that 8 bases were deleted at the 60th base in the Dular allele, resulting in a frame-shift mutation and loss of function of the gene. This is consistent with the chlorosis mutant phenotype of Dular. In addition, previous studies have shown that many chlorosis mutants of seedlings are related to PPR proteins. Hence, we presume that the PPR gene is the candidate for cisc(t). 相似文献
920.
LIU TungSheng 《科学通报(英文版)》2010,55(6):520-529
Detailed magnetostratigraphic and rock magnetic investigations on L8-S12 of the Songjiadian loess section in the Sanmenxia area,southernmost margin of the Chinese Loess Plateau were conducted in this study.Matuyama/Brunhes (M/B) boundary occurred at the bottom of the loess unit L8.The top and bottom boundaries of the Jaramillo polarity subchron are found in the middle of L10 and the bottom of L12,respectively.Magnetic fabric of the loess layers maintains the original depositional features and the recorded r... 相似文献