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低偏差蒙特卡罗序列的量子遗传算法 被引量:3
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作者 黄山 苏一丹 +1 位作者 覃华 蒙祖强 《小型微型计算机系统》 CSCD 北大核心 2017年第2期398-404,共7页
针对量子遗传算法存在迭代次数多、计算时间长、容易陷入局部极值的问题,提出一种低偏差蒙特卡罗序列量子遗传算法,利用低偏差序列良好的均匀性,实现量子遗传算法探索与利用的平衡.首先,提出新的低偏差序列Hε量子门来更新量子态形式的... 针对量子遗传算法存在迭代次数多、计算时间长、容易陷入局部极值的问题,提出一种低偏差蒙特卡罗序列量子遗传算法,利用低偏差序列良好的均匀性,实现量子遗传算法探索与利用的平衡.首先,提出新的低偏差序列Hε量子门来更新量子态形式的种群,提高算法探索量子态的能力,减少算法的迭代次数;其次,提出Pareto集邻域搜索,在当前近优解上用低偏差序列在当前解上进行邻域搜索,以寻找更优的解.在5个复杂函数优化问题上验证本文算法,实验结果表明:所提算法的寻优能力较传统量子遗传算法更强,解的质量有两个数量级以上的提高;算法的计算时间和迭代次数亦优于传统量子遗传算法,引入低偏差序列实现量子遗传算法探索与利用的平衡是可行的. 展开更多
关键词 量子遗传算法 低偏差序列 低偏差序列Hg量子 Pareto集邻域搜索
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卷积(卷积和)的门函数解析算法的因果性
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作者 李竹英 《华中理工大学学报》 CSCD 北大核心 1995年第4期44-47,共4页
探讨了卷积(卷积和)的门函数(门序列)解析算法的因果性;根据含参量的门函数(门序列)的定义条件,着重论述了其在因果系统及非因果系统的卷积(卷积和)之解析式中的普遍存在原理。结论是:无论是在因果系统还是非因果系统中,卷... 探讨了卷积(卷积和)的门函数(门序列)解析算法的因果性;根据含参量的门函数(门序列)的定义条件,着重论述了其在因果系统及非因果系统的卷积(卷积和)之解析式中的普遍存在原理。结论是:无论是在因果系统还是非因果系统中,卷积的门函数解析算法及离散系统卷积和的门序列解析算法是普遍适用的;杜哈梅尔积分的全解析算法也是普遍适用的。 展开更多
关键词 函数 门序列 因果性 卷积和 工程数学
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用FPGA实现嵌入式视频图像信号实时采集 被引量:2
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作者 刘超 钱光弟 《实验科学与技术》 2005年第2期12-15,共4页
提出了一种基于FPGA的嵌入式视频图像信号实时采集系统,采用SAA7111A对信号进行A/D变换,并用FPGA与SDRAM实现大容量的双帧缓存。详细说明双口存储器、有限状态机的实现及隔行扫描到逐行扫描的转换、乒乓互锁工作机制等。本系统可用在安... 提出了一种基于FPGA的嵌入式视频图像信号实时采集系统,采用SAA7111A对信号进行A/D变换,并用FPGA与SDRAM实现大容量的双帧缓存。详细说明双口存储器、有限状态机的实现及隔行扫描到逐行扫描的转换、乒乓互锁工作机制等。本系统可用在安全监控、工业图像检测、机器视觉等领域。 展开更多
关键词 现场可编程门序列FPGA(Fied Programmable Gate Array) 同步动态随机存取存储器SDRAM(Synchronous Dynamic Random Access Memory) 视频图像采集 双口存储器 SAA7111A
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利用DA算法实现大规模FIR滤波器 被引量:8
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作者 李林 《实验科学与技术》 2006年第2期7-9,共3页
分布式算法是一种广泛地应用在可编程逻辑序列(FPGA)和ASIC设计中计算乘积和的算法。DA算法的处理速度仅与输入的位宽有关,对于大规模乘积和的运算,其计算速度有着明显的优势。当输入位宽过大时,可以将DA算法改进成并串结构以获得更快... 分布式算法是一种广泛地应用在可编程逻辑序列(FPGA)和ASIC设计中计算乘积和的算法。DA算法的处理速度仅与输入的位宽有关,对于大规模乘积和的运算,其计算速度有着明显的优势。当输入位宽过大时,可以将DA算法改进成并串结构以获得更快的处理速度。该文对在FPGA中利用DA算法实现大规模FIR滤波器,提出了具体的实现方案。 展开更多
关键词 分布式算法 可编程逻辑门序列 FIR滤波器
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基于FPGA的以太网与E1网中的同步动态随机存储控制器设计 被引量:1
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作者 符世龙 陈松岩 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第3期360-365,共6页
为了实现不同速率数据链路通信的相互转换,提出了一种利用现场可编程门序列(FPGA)设计并实现可对同步动态随机存储器(SDRAM)进行数据缓存并高速读写的控制器.该控制器采取状态机和令牌环机制,通过对SDRAM操作,实现了双向4路的跨时钟域... 为了实现不同速率数据链路通信的相互转换,提出了一种利用现场可编程门序列(FPGA)设计并实现可对同步动态随机存储器(SDRAM)进行数据缓存并高速读写的控制器.该控制器采取状态机和令牌环机制,通过对SDRAM操作,实现了双向4路的跨时钟域的匹配.该控制器适用于任意长度的以太网帧和其他类型的数据相互转换. 展开更多
关键词 同步动态随机存储器 跨时钟域通信 现场可编程门序列 以太网帧
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基于FPGA的并联DC-DC电源系统无线发射装置的设计
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作者 胡瑾 刘升 +1 位作者 葛芦生 秦富 《自动化与仪器仪表》 2014年第12期88-90,共3页
在无线传输的系统设计中,越来越多的使用到了DSP+FPGA的方案,由FPGA做时序控制,而DSP做复杂的算法处理,这样的分工可以使二者各尽其能,使整个系统的性能最优。本文分别从基带和射频前端两方面对无线发射装置进行硬件设计,重点研究的是基... 在无线传输的系统设计中,越来越多的使用到了DSP+FPGA的方案,由FPGA做时序控制,而DSP做复杂的算法处理,这样的分工可以使二者各尽其能,使整个系统的性能最优。本文分别从基带和射频前端两方面对无线发射装置进行硬件设计,重点研究的是基带DSP与FPGA的接口设计和超外差架构射频前端FPGA对本振、A/D或D/A的动态配置。最后自编程序证明该方案行之有效,且具有一定的通用性和灵活性。 展开更多
关键词 现场可编程门序列 设计 超外差架构 动态配置
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Cloning and Sequence Analysis of 5′ Flanking Region and Exon of Inhibin α Precursor Gene in Goats
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作者 何远清 马晓珂 张春霞 《Agricultural Science & Technology》 CAS 2009年第4期83-86,90,共5页
[Objective] The aim of this study was to reveal the relationship between inihibin (INH) α precursor gene and seasonal reproduction of goats, and investigate the evolutionary conservation of INHα precursor gene. [ ... [Objective] The aim of this study was to reveal the relationship between inihibin (INH) α precursor gene and seasonal reproduction of goats, and investigate the evolutionary conservation of INHα precursor gene. [ Method] Cloning and sequence analysis of 5' flanking region and exon of inihibinα (INHE) precursor gene in twenty ewes between non-seasonal estrous breed (Haimen goats) and seasonal estrous breed (Anhui white goats) was analyzed in this study. [ Result] Compared with Anhui white goats, INHα precursor gene in Haimen goats had three SNP but no amino acid change, while its nucleotide homology was 99.7% and amino acid homology was 100%. The nucleotide homology of INHα precursor gene in goat, cattle, pig, person, chicken, horse, rat and dog ranged from 12.7% to 96.5%. [ Conclusion] INHα precursor gene tends to be highly conserved in species, and any change of nucleotide and amino acid maybe directly influence the function of the whole gene coding and regulation. 展开更多
关键词 GOAT Reproductively Inhibin α precursor gene CLONING Sequence analysis
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Cloning and Analysis of Calmodulin Gene from Porphyra yezoensis Ueda (Bangiales, Rhodophyta) 被引量:3
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作者 WANG Mengqiang MAO Yunxiang +2 位作者 ZHUANG Yunyun KONG Fanna SUI Zhenghong 《Journal of Ocean University of China》 SCIE CAS 2009年第3期247-253,共7页
In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chai... In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exons and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca2+ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta. 展开更多
关键词 Porphyra yezoensis CALMODULIN DESICCATION sequence analysis
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Detection of H pylori antibody profile in serum by protein array 被引量:2
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作者 Feng-Chan Han Xu-Jun Li +6 位作者 Hong Jiang Li-Peng Qin Ding Li Yan-Hai Guo Zhi-Guang Liu Li Zhang Xiao-Jun Yan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第25期4044-4048,共5页
AIM: To detect multiple H pylori antibodies in serum samples of individuals who carryHpylori by protein array. METHODS: Recombinant H pylori antigens, urease B subunit (UreB), vacuolating toxin A (VacA) and cyto... AIM: To detect multiple H pylori antibodies in serum samples of individuals who carryHpylori by protein array. METHODS: Recombinant H pylori antigens, urease B subunit (UreB), vacuolating toxin A (VacA) and cytotoxin associated gene A protein (CagA), were prepared and immobilized in matrixes on nitrocellulose membrane by robotics to bind the specific immunoglobulin G (IgG) antibodies in serum. Staphylococcus protein A (SPA) labeled by colloid gold was used to integrate the immuno-complex and gave red color signal. The scanner based on charge-coupled device (CCD) could collect the image signal and convert it into digital signal. RESULTS: When human IgG was printed on the membrane in increasing concentrations and incubated with immunogold, a linear dose response curve was obtained and the detection limit for IgG was about 0.025 ng. The cutoff values, which were defined as the mean grey level plus 3 times of standard deviation, were 27.183, 28.546 and 27.402, for anti-UreB IgG, anti- CagA IgG and anti-VacA IgG, respectively, as 400 human serum samples with negative H pylori antibodies were detected by the protein array. When 180 serum samples from patients in hospital were employed for detection of IgG against UreB, CagA and VacA, the sensitivity of the protein array was 93.4%, 95.4%, 96.0%, and the specificity was 94.8%, 94.4% and 97.5%, respectively, as compared with the results obtained by ELISA. The assay also showed high reproducibility, uniformity and stability, and the results were available within 30 min. CONCLUSION: The protein array is a very practical method for rapid detection of multiple antibodies in serum samples. It is especially useful for large scale epidemiological investigation of the infection of Hpylori. 展开更多
关键词 Helicobacter pylori Protein array ANTIBODY IMMUNOGOLD
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Molecular phylogeny of oligotrich genera Omegastrombidium and Novistrombidium(Protozoa,Ciliophora) for the systematical relationships within Family Strombidiidae 被引量:1
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作者 张倩倩 伊珍珍 +3 位作者 徐大鹏 AL-RASHEID Khaled A.S. 龚骏 宋微波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期769-777,共9页
The phylogeny of the oligotrich ciliates is currently a hot debate despite the availability of both morphological and molecular data.In the present paper,further small subunit rRNA(SS rRNA) genes were analyzed from th... The phylogeny of the oligotrich ciliates is currently a hot debate despite the availability of both morphological and molecular data.In the present paper,further small subunit rRNA(SS rRNA) genes were analyzed from the Genera Omegastrombidium and Novistrombidium,as well as from Strombidium,and combined with three new SS rRNA sequences from Strombidium basimorphum,S.sulcatum population QD-1,and Novistrombidium testaceum population GD.The phylogenetic positions of these organisms were inferred using Bayesian inference,Maximum Likelihood,and Maximum Parsimony methods.The main results are:(1) the SS rRNA gene sequence analyses match the recent findings about the molecular evolution of oligotrichs,indicating that the family Strombidiidae is paraphyletic;(2) the Genus Omegastrombidium is separated from the Genus Strombidium,as shown in recent cladistic analyses;(3) morphospecies in Genus Novistrombidium,based on similarity of somatic ciliature,are separated from each other in all topological trees,indicating that this genus could be a paraphyletic group;(4) the molecular data indicate a possibility of paraphyly for the genus Strombidium;and(5) the similarities of the SS rRNA gene of specimens identified as S.sulcatum and S.inclinatum are 99.8%-100%.However,present knowledge on the oligotrichs sensu stricto is still insufficient and further studies based on both molecular and other technologies are required. 展开更多
关键词 Omegastrombidium Novistrombidium Strombidium SS rRNA PHYLOGENY
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Realization of Two-Qutrit Quantum Gates with Control Pulses 被引量:4
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作者 ZHANG Jie DI Yao-Min WEI Hai-Rui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期653-658,共6页
We investigate the realization of 2-qutrit logic gate in a bipartite 3-level system with qusi-Ising interaction. On the basis of Caftan decomposition of matrices, the unitary matrices of 2-qutrit are factorized into p... We investigate the realization of 2-qutrit logic gate in a bipartite 3-level system with qusi-Ising interaction. On the basis of Caftan decomposition of matrices, the unitary matrices of 2-qutrit are factorized into products of a series of realizable matrices. It is equivalent to exerting a certain control field on the system, and the control goal is usually gained by a sequence of control pulses. The general discussion on the realization of 2-qutrit logic gate is made first, and then the realization of the ternary SWAP gate and the ternary √SWAP gate are discussed specifically, and the sequences of control pulses and drift processes implementing these gates are given. 展开更多
关键词 Caftan decomposition 2-qutrit system ternary SWAP gate ternary √SWAP gate
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Identification and characterization of a Dna J gene from red alga Pyropia yezoensis(Bangiales, Rhodophyta) 被引量:1
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作者 刘娇 李先超 +1 位作者 唐学玺 周斌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第2期405-411,共7页
Members of the Dna J family are proteins that play a pivotal role in various cellular processes, such as protein folding, protein transport and cellular responses to stress. In the present study, we identified and cha... Members of the Dna J family are proteins that play a pivotal role in various cellular processes, such as protein folding, protein transport and cellular responses to stress. In the present study, we identified and characterized the full-length Dna J c DNA sequence from expressed sequence tags of Pyropia yezoensis( Py Dna J) via rapid identification of c DNA ends. This c DNA encoded a protein of 429 amino acids, which shared high sequence similarity with other identified Dna J proteins, such as a heat shock protein 40/Dna J from Pyropia haitanensis. The relative m RNA expression level of Py Dna J was investigated using real-time PCR to determine its specific expression during the algal life cycle and during desiccation. The relative m RNA expression level in sporophytes was higher than that in gametophytes and significantly increased during the whole desiccation process. These results indicate that Py Dna J is an authentic member of the Dna J family in plants and red algae and might play a pivotal role in mitigating damage to P. yezoensis during desiccation. 展开更多
关键词 DNAJ DESICCATION life cycle mRNA expression Pyropia yezoensis
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Grateloupia ramosa Wang & Luan sp. nov. (Halymeniaceae, Rhodophyta), a new species from China based on morphological evidence and comparative rbcL sequences 被引量:5
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作者 曹翠翠 刘淼 +3 位作者 郭少茹 赵丹 栾日孝 王宏伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第2期283-294,共12页
Grateloupia ramosa Wang & Luan sp. nov.(Halymeniaceae, Rhodophyta) is newly described from Hainan Province, southern China. The organism has the following morphological features:(1) purplish red, cartilaginous and... Grateloupia ramosa Wang & Luan sp. nov.(Halymeniaceae, Rhodophyta) is newly described from Hainan Province, southern China. The organism has the following morphological features:(1) purplish red, cartilaginous and lubricous thalli 5–10 cm in height;(2) compressed percurrent axes bearing abundant branches with opposite arrangement;(3) claw-like apices on top, constricted to 2–4 cm at the base;(4) cortex consisting of 3–6 layers of elliptical or anomalous cells and a medulla covered by compact medullary filaments;(5) reproductive structures distributed throughout the thallus, especially centralized at the bottom of the end portion of the branches; and(6) 4-celled Carpogonial branches and 3-celled auxiliary-cell branches, both of the Grateloupia-type. The morphological diff erences were supported by molecular phylogenetics based on ribulose-1, 5-bisphosphate carboxylase/oxygenase( rbc L) gene sequence analysis. There was only a 1 bp divergence between specimens collected from Wenchang and Lingshui of Hainan province. The new species was embedded in the large Grateloupia clade of the Halymeniaceae. The pairwise distances between G. ramosa and other species within Grateloupia ranged from 26 to 105 bp, within pairwise distances of 13–111 bp between species of the large genus Grateloupia in Halymeniaceae. Thus, we propose this new species as G. ramosa Wang & Luan sp. nov. 展开更多
关键词 GRATELOUPIA Grateloupia ramosa HALYMENIACEAE morphology rbcL sequence Rhdophyta
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Analysis of expressed sequence tags from the Ulva prolifera (Chlorophyta) 被引量:4
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作者 牛建峰 胡海岩 +3 位作者 胡松年 王广策 彭光 孙松 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期26-36,共11页
In 2008, a green tide broke out before the sailing competition of the 29th Olympic Games in Qingdao. The causative species was determined to be Enteromorpha prolifera (Ulva prolifera O. F. Miiller), a familiar green... In 2008, a green tide broke out before the sailing competition of the 29th Olympic Games in Qingdao. The causative species was determined to be Enteromorpha prolifera (Ulva prolifera O. F. Miiller), a familiar green macroalga along the coastline of China. Rapid accumulation of a large biomass of floating U. prolifera prompted research on different aspects of this species. In this study, we constructed a nonnormalized cDNA library from the thalli of U. prolifera and acquired 10072 high-quality expressed sequence tags (ESTs). These ESTs were assembled into 3 519 nonredundant gene groups, including 1 446 clusters and 2 073 singletons. After annotation with the nr database, a large number of genes were found to be related with chloroplast and ribosomal protein, GO functional classification showed 1 418 ESTs participated in photosynthesis and 1 359 ESTs were responsible for the generation of precursor metabolites and energy. In addition, rather comprehensive carbon fixation pathways were found in U. prolifera using KEGG. Some stress-related and signal transduction-related genes were also found in this study. All the evidences displayed that U. prolifera had substance and energy foundation for the intense photosynthesis and the rapid proliferation. Phylogenetic analysis of cytochrome c oxidase subunit I revealed that this green-tide causative species is most closely affiliated to Pseudendoclonium akinetum (Ulvophyceae). 展开更多
关键词 green tide Ulva Prolifera expressed sequence tag (EST) filamentous green alga rapid growth PROLIFERATION
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Potential implications of Helicobacter pylori-related neutrophil-activating protein 被引量:5
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作者 Jannis Kountouras Christos Zavos +7 位作者 Georgia Deretzi Emmanuel Gavalas Dimitrios Chatzopoulos Panagiotis Katsinelos Elena Tsiaousi Stergios Gagalis Stergios A Polyzos Ioannis Venizelos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期489-490,共2页
Helicobacter pylori (H. pylori) virulence factors pro- mote the release of various chemoattractants/inflam- matory mediators, including mainly the neutrophil- attractant chemokine interleukin-8 and neutrophil- activ... Helicobacter pylori (H. pylori) virulence factors pro- mote the release of various chemoattractants/inflam- matory mediators, including mainly the neutrophil- attractant chemokine interleukin-8 and neutrophil- activating protein (NAP), involved in H. pylor/-induced gastric pathologies. Co-administration of Chios mastic gum (CMG), which inhibits H. pylor/NAP, with an H. pylori eradication regimen might add clinical benefits against H. pylori-related gastric pathologies, but pos- sibly not CMG as main therapy. Although H. pylori NAP and other H. pylori-related cytotoxins [i.e., vaculating cytotoxin (VacA)] appear to play a major role in gener- ating and maintaining the H. pylori-associated gastric inflammatory response and H. pylor/NAP is a promising vaccine candidate against H. pylori infection (H. pylori-1), concerns regarding its potential drawbacks, particularly neurogenic ones, due to possible cross- mimicry, should be considered. Possible cross-mimicry between H. p, vlor/ NAP and/or bacterial aquaporin (AQP) and neural tissues may be associated with the anti-AQP-4 antibody-related neural damage in multiple sclerosis (MS)/neuromyelitis optica patients. Moreover, the sequence homology found between H. pylori VacA and human Na+/K+-ATPase A subunit suggests that antibodies to VacA involve ion channels in abaxonal Schwann cell plasmalemma resulting in demyelination in some patients. A series of factors have been im- plicated in inducing blood-brain barrier (BBB) disrup- tion, including inflammatory mediators (e.g., cytokines and chemokines induced by H. pylor/-I) and oxidative stress. BBB disruption permits access of AQP4-specific antibodies and T lymphocytes to the central nervous system, thereby playing a major role in multiple sclero- sis pathogenesis. Relative studies show a strong asso- ciation between H. pylori-I and MS. H. pylor/-I induces humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mim- icry), cross-react with components of nerves, thereby contributing and perpetuating neural tissue damage. Finally, H. pylori NAP also plays a possible pathoge- netic role in both gastric and colon oncogenesis. 展开更多
关键词 Helicobacter pylor/ Neutrophil-activatingprotein Chios mastic gum Cross-mimicry Multiplesclerosis DEMYELINATION Gastric carcinogenesis
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Episodic Orogeny Deduced from Coeval Sedimentary Sequences in the Foreland Basin and Its Implication for Uplift Process of Longmen Mountain,China 被引量:3
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作者 LI Yong SU De-chen +4 位作者 ZHOU Rong-jun LI Hai-bing Alexander L.DENSMORE YAN Liang YAN Zhao-kun 《Journal of Mountain Science》 SCIE CSCD 2013年第1期29-42,共14页
Longmen Mountain located at the boundary between the Sichuan Basin and Tibetan Plateau,representing the steepest gradient of any edges of the plateau.Three endmember models of uplift process and mechanism have been pr... Longmen Mountain located at the boundary between the Sichuan Basin and Tibetan Plateau,representing the steepest gradient of any edges of the plateau.Three endmember models of uplift process and mechanism have been proposed,including crustal thickening,crustal flow,and crustal isostatic rebound.Here we use coeval sedimentary sequences in the foreland basin to restraint uplift process and mechanism in the Longmen Mountain.The more than 10,000 m thick Late TriassicQuaternary strata filled in this foreland basin and can be divided into six megasequences that are distinguished as two distinct types.The first type is the wedge-shaped megasequences which are sedimentary response of strong active thrust loading events,characterized by a high rate of subsidence and sediment accumulation,coarsening-upward succession and a dual-sourced sediment supply.This type includes Late Triassic,Late Jurassic to Early Cretaceous and Late Cretaceous to Paleogene megasequences.The second type is the tabular megasequences,characterized by the low rate of subsidence and sediment accumulation,finingupward succession,and a single-sourced sediment supply,which is sedimentary response of isostatic rebound and erosion unloading.This type includes the Early to Middle Jurassic,Middle Cretaceous and Neogene to Quaternary megasequences.Basing on sedimentary,active tectonic,geomorphic evidence,we infer that the direction has been reversed from SSWdirected sinistral strike-slip to NNE-directed dextral strike-slip during 40-3.6 Ma,and since 3.6 Ma,the Longmen Mountain thrust belt belong to times of isostatic rebound and erosional unloading with NNEdirected dextral strike-slip.This suggests that crustal isostatic rebound is a primary driver for uplift and topography of the present Longmen Mountain.The Wenchuan(Ms8.0) earthquake,which ruptured a large thrust fault with NNE-directed dextral strikeslip along the range front,is an active manifestation of this crustal isostatic rebound process with dextral strike-slipping and shortening.This process may be the cause for the Wenchuan Earthquake and the apparent paradox of high relief,little shortening,the relative dearth of historical seismicity in the region. 展开更多
关键词 Wedge-shaped megasequence Tabular megasequence Orogenic loading Erosional unloading Uplift process Longmen Mountain Foreland basin
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Automated Recovery of the 2012 Sumatera Aftershock Sequence Using Waveform Cross Correlation
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作者 Dmitry Bobrov Urtnasan Khukhuudei Ivan Kitov Kirill Sitnikov Lassina Zerbo 《Journal of Earth Science and Engineering》 2013年第7期437-460,共24页
We assess the performance of waveform cross correlation as applied to automatic and interactive processing of the aftershock sequence of the April 11, 2012 Sumatera Ms(IDC) = 8.2 earthquake. The XSEL (cross correla... We assess the performance of waveform cross correlation as applied to automatic and interactive processing of the aftershock sequence of the April 11, 2012 Sumatera Ms(IDC) = 8.2 earthquake. The XSEL (cross correlation standard event list) is compared to the REB (Reviewed Event Bulletin) issued by the IDC (International Data Centre). The latter includes 1,181 aftershocks between April 11 and May 25. To automatically recover the sequence, sixteen aftershocks were selected from the IDC SEL3 (Standard Event List) available on April 13 and used as master events. Waveform templates from only seven IMS (International Monitoring System) array stations with the largest SNR (signal-to-noise ratio) for the main shock were used to calculate cross correlation coefficients. Approximately 620,000 arrivals were detected and then used to build events according to the IDC definition. After conflict resolution between event hypotheses with similar arrivals found by more than one master, all survived hypotheses populated the XSEL. The total number of distinct hypotheses was 4,924, with 2,763 hypotheses not matched by the REB, i.e. potentially new REB events. To evaluate the quality of the XSEL, we randomly selected a representative portion (-15%) from 2,763 hypotheses and reviewed them interactively according to standard IDC rules and guidelines. There were 119 new REB events built and 145 XSEL hypotheses rejected. Several frequency and probability density distributions have been constructed for all detections, the associated detections, the XSEL detections, the detections in the new REB, and rejected events. 展开更多
关键词 Cross correlation array seismology nuclear test monitoring IDC CTBT
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Phylogeny of subclass Scuticociliatia(Protozoa,Ciliophora) using combined data inferred from genetic,morphological,and morphogenetic evidence
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作者 伊珍珍 王艳刚 +2 位作者 林晓凤 Khaled A.S.AL-RASHEID 宋微波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期778-784,共7页
Gene sequence-based genealogies of scuticociliates are different from those produced by morphological analyses.For this reason,11 representative scuticociliates and two ambiguously related genera were chosen to test t... Gene sequence-based genealogies of scuticociliates are different from those produced by morphological analyses.For this reason,11 representative scuticociliates and two ambiguously related genera were chosen to test the ability of combined phylogenetic analyses using both gene sequences and morphological/morphogenetic characteristics.Analyses of both the SSrRNA gene sequences and the combined datasets revealed a consistent branching pattern.While the terminal branches and the order level relationships were generally well resolved,the family level relationships remain unresolved.However,two other trees based on ITS1-5.8S-ITS2 region sequences and morphological/morphogenetic characters showed limited information,due to a lack of informative sites in these two datasets.Our data suggest,however,that the combined analysis of morphological/morphogenetic characters and gene sequences did produce some changes to the phylogenetic estimates of this group. 展开更多
关键词 CILIOPHORA Scuticociliatia phylogenetic analyses combined data
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基于FPGA的并联DC-DC电源系统无线收发装置的研究与优化
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作者 黄义忠 刘升 +1 位作者 胡瑾 葛芦生 《自动化与仪器仪表》 2015年第6期1-3,共3页
详细介绍了无线通信在并联DC-DC电源系统中的应用,针对并联DC-DC电源系统单次传输量小、频率高的特点,结合现有的BPSK通信系统,利用FPGA对时序控制的优越性,完成整个通信系统的优化。介绍其优化实现,着重于帧长和码速率的修改,同时给出... 详细介绍了无线通信在并联DC-DC电源系统中的应用,针对并联DC-DC电源系统单次传输量小、频率高的特点,结合现有的BPSK通信系统,利用FPGA对时序控制的优越性,完成整个通信系统的优化。介绍其优化实现,着重于帧长和码速率的修改,同时给出相关的优化结果。 展开更多
关键词 无线通信 并联DC-DC BPSK 现场可编程门序列
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Variations of shear wave splitting in the 2013 Lushan Ms7.0 earthquake region 被引量:12
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作者 CHANG LiJun DING ZhiFeng WANG ChunYong 《Science China Earth Sciences》 SCIE EI CAS 2014年第9期2045-2052,共8页
In this paper, variations of shear wave splitting in the 2013 Lushan Ms7.0 earthquake sequence were studied. By analyzing shear wave particle motion of local events in the shear wave window, the fast polarization dire... In this paper, variations of shear wave splitting in the 2013 Lushan Ms7.0 earthquake sequence were studied. By analyzing shear wave particle motion of local events in the shear wave window, the fast polarization directions and the delay time between fast and slow shear waves were derived from seismic recordings at eight stations on the southern segment of the Longmenshan fault zone. In the study region, the fast polarization directions show partition characteristics from south to north. And the systematic changes of the time delays between two split shear waves were also observed. As for spatial distribution, the NE fast polarization directions are consistent with the Longmenshan fault strike in the south of focal region, whereas the NW fast direction is parallel to the direction of regional principal compressive stress in the north of focal region. Stations BAX and TQU are respectively located on the Central and Front-range faults, and because of the direct influence of these faults, the fast directions at both stations show particularity. In time domain, after the main shock, the delay times at stations increased rapidly, and decreased after a period of time. Shear-wave splitting was caused mostly by stress-aligned microcracks in rock below the stations. The results demonstrate changes of local stress field during the main shock and the aftershocks. The stress on the Lushan Ms7.0 earthquake region increased after the main shock, with the stress release caused by the aftershocks and the stress reduced in the late stage. 展开更多
关键词 shear wave splitting crustal stress Lushan Ms7.0 earthquake fast wave direction delay time
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