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Association between complementary factor H Y402H polymorphisms and age-related macular degeneration in Chinese: Systematic review and meta-analysis

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International Journal of Ophthalmology(English edition) 2012年第2期5卷 242-246页

作者： Yan-Long quan Ai-yi Zhou and Zhao-Hui Feng Department of Ophthalmology the Second Affiliated Hospital of Medical College of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China

AIM: Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world and complement factor H (CFH) polymorphism has been found to associate with the AMD. To investigate whether the Y402H variant in CFH is associated with AMD in Chinese populations, a systematic review and meta-analysis were performed to estimate the magnitude of the gene effect and the possible mode of action. METHODS: A meta-analysis was performed using data available from ten case-control studies assessing association between the CFH Y402H polymorphism and AMD in Chinese populations involving 1538 AMD. Data extraction and study quality assessment were performed in duplicate. Summary odds ratios (ORs) and 95% confidence intervals (CIs) an allele contrast and genotype contrast were estimated usingfixed- effects models. The Q-statistic test was used to assess heterogeneity, and Funnel plot was used to evaluate publication bias. RESULTS: Seven of ten case-control studies were neovascular AMD, and few studies came from west and north of China. There was strong evidence for association between CFH and AMD in Chinese population, with those having risk allele C 2.35 times more likely to have AMD than subjects with T allele. Evidence of publication bias was not observed in our meta-analysis. CONCLUSION: This meta-analysis summarizes the strong evidence for an association between CFH and AMD in Chinese and indicates each C allele increasing the odds of AMD by 2.33-fold. But more evidences about the relation between CFH polymorphism and different type of Chinese AMD from various district were needed.

关键词： age-related macular degeneration complement factor H polymorphism meta-analysis Chinese population

Evaluation of terrestrial radiation in the Chengdu Plain using 1/250,000-scale geochemical prospecting data

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Nuclear Science and Techniques 2017年第10期28卷 31-36页

作者： Qing-Xian Zhang Jian-Kun Zhao yi Gu Liang-quan Ge Yuan-Qing Huang Sichuan-Provincial Key Laboratory of Nuclear Technologyin Geosciences Chengdu University of TechnologyChengdu 610059China Sichuan Nuclear Geology Institute Chengdu 610061China

Based on the geochemical prospecting data, we have calculated the gamma absorbed dose rates in air 1 m above the ground surface in the Chengdu Plain, analyzed the relationship between the geological conditions and the distribution of the natural radionuclides, and preliminarily studied the influence of the geological conditions on the terrestrial radiation level in the Chengdu Plain. The result shows that the terrestrial radiation level in the Chengdu Plain is slightly lower than the average values of China and varies greatly according to the complex geological conditions.

关键词：成都平原地面辐射地球化学找矿评价天然放射性核素地质条件辐射水平普查数据

Feeding time changed the diurnal composition of intestinal microbiota in Pelteobagrus fulvidraco

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Journal of Oceanology and Limnology 2024年第6期42卷 2034-2044页

作者： Chuanjie QIN Jing XU quan GONG Zhengyong WEN yi LIU Qingchao SHI Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River Neijiang Normal UniversityNeijiang 641000China College of Life Science Neijiang Normal UniversityNeijiang 641000China Fisheries Research Institute‚Sichuan Academy of Agricultural Sciences Chengdu 611730China

Although the effects of diet on intestinal microbiotas have been well investigated,the effect of feeding time on the rhythm of gut microbiota remains uncertain.A 9-week feeding trial on Pelteobagrus fulvidraco was *** triplicate groups of fish were fed identically either at 8:00(day)or at 20:00(night).After 9 weeks,three fish from each cage were sacrificed every 4 h for 24 *** intestinal contents were analyzed using high-throughput *** phyla(Fusobacteria,Proteobacteria,and Verrucomicrobia),and three genera(Cetobacterium,Akkermansia,and Clostridium)were dominant at every time ***,33.02%of detected amplicon sequence variants showed cyclical variations in fish fed at 20:00,and 3.47%in fish fed at 8:*** the top 20 genera,17 showed cyclical variations in the 20:00 group,and only two in the 8:00 ***,Ralstonia,Mycobacterium,Lactococcus,Halomonas,Akkermansia,and Acinetobacter contributed more to the predicted functional ***,144 and 38 pathways exhibited daily cyclical fluctuations in fish fed at 20:00 and 8:00,***,certain intestinal microorganisms showed a circadian rhythm in ***,and this circadian rhythm was affected by shifted feeding times.

关键词： diurnal fluctuation Pelteobagrus fulvidraco gut microorganism feeding time

Investigation of the interaction between HIV-1 DNA and cyclic peptides by electrospray ionization mass spectrometry

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Chinese Chemical Letters 2009年第3期20卷 330-333页

作者： yi quan Liu Hui Hui Li Yun Hua Ye Gu Yua Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beifing 100871 China School of Chemistry and Environmental Science Nanjing Normal University Nanjing 210097 China

The interaction between HIV-1 DNA and five cyclic peptides （CP1-CP5） was investigated using electrospray ionization mass spectrometry （ESI-MS）. It revealed that CP1 [c（Ala-Tyr-Leu-Ala-Gly）] and CP4 [c（Pro-D-Tyr... 详细信息

关键词： HIV-1 DNA Cyclic peptide ESI-MS

Rare Earth Polymer Complex Catalyst for Ring Opening Polymerization of Epichlorohydrin

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Chemical Research in Chinese Universities 1995年第3期11卷 238-242页

作者： Shen, Zhi-quan Jiang, Dong-lin Zhang, yi-feng

novel complex composed of chitosan(CS) and neodymium(Nd ) was preparedand the ring opening polymerization of epichlorohydrin(ECH) with a new catalyticsystem comprising this new rare earth polymer complex(CS . Nd) has been suc-cessfully carried out for the first time. It has been found that the new catalytic sys-tem composed of CS . Nd-AI (i-Bui,-methyl benzoxylate( Ⅲ) is an excellent cata-lyst for the polymerization of epichlorohydrin which shows a catalytic activity 60times higher tlian that of conventional rare earth catalyst. Under the following re-action conditions : Nd - 1 ×10￣(-6) mo1/g monomer, A1/Nd= 60 molar ratio , Ⅲ/A1=-0. 6 molar ratio, the monomer conversion and PECH molecular weight are as highas 92.9% and 28. 2 × 10￣5 respectively and the polymer prepared has a low crys-tallinity. The kinetics investigation revealed that the polymerization has a short in-duction period of several minutes and the rate of polymerization is of first orderwith respect to the monomer concentration and the catalyst concentration. The acti-vation energy of the polymerization reaction was found to be 25. 5 kJ/mol which islower than that of conimon rare earth catalvst.

关键词： Neodymium cliitosan complex Epichlorohydrin Ring opening poly-merlzation

A Stochastic Optimization Approach for Dynamic Adaptive Streaming over NDN

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Journal of Communications and Information Networks 2021年第3期6卷 267-279页

作者： Xiaobin Tan Shunyi Wang quan Zheng Bei Liu yi He Xiangyang Wu Laboratory for Future Networks the University of Science and Technology of ChinaHefei 230027China The 54th Research Institute of China Electronic Technology Corporation Shijiazhuang 050081China

Nowadays,video streaming counts for the major part of network traffic over the ***,on account of the host-to-host mechanism of the traditional IP network,video distribution over IP-based Internet encounters ***,a new proposed future Internet architecture,named data networking(NDN)can improve the performance of video distribution by its features such as in-network storage,multi-path forwarding,*** this paper,we design an adaptive bitrate algorithm based on Lyapunov optimization theory over NDN to optimize the long-term quality-of-experience(QoE)of video distribution while ensuring the stability of the whole *** the network condition is abundant and stable,the problem can be simplified by approximating to a fixed-slot queuing model,but the theoretical performance will degrade when the network status is poor and fluctuate ***,we divide the problem into two models of fixed time slot and non-fixed time slot and design two Lyapunov optimization algorithms to adapt different network *** proposed algorithms do not require prior knowledge of the network bandwidth and are capable of running online with the client’s available *** and realistic experiment results demonstrate that our algorithms perform better than others in NDN.

关键词： named data networking dynamic adaptive streaming scalable video coding Lyapunov optimization quality of experience

Rate estimate for regular LDPCA codec in distributed video coding

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 50-54页

作者： MING Yang-yang YANG Bo quan Zi-yi MEN Ai-dong School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Accumulated low density parity check （LDPCA） codec is proposed for DISCOVER project in distributed video coding （DVC）, which offers flexible coding rate. Although it can use feedback channel to adapt the rate to the correlation of the video, but in real applications, using feedback channel can not always be possible. To solve this problem, some researchers proposed estimating the code rate at the encoder but the performance was not very good. Based on their researches, this paper considers the impact of convergence rate for iteration on rate estimate, which can be calculated using its check matrix. As a pilot study, this paper pays attention to the regular LDPCA codec. At the same time, it considers the impact of deviation in the estimated crossover probability, which gives some constraints to rate estimate. In the experiment, the proposed algorithm can improve the rate-distortion performance by up to 1 dB-1.2 dB.

关键词： LDPCA distributed video coding rate estimate regular LDPCA codec crossover probability deviation

Identification of methylation profile of HOX genes in extrahepatic cholangiocarcinoma

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World Journal of Gastroenterology 2011年第29期17卷 3407-3419页

作者： yi Shu Bing Wang Ji Wang Jian-Ming Wang Sheng-quan Zou General Surgery Department of Tongji Hospital Tongji Medical College of Huazhong University of Science and Technology1095 Jiefang AvenueWuhan 430030Hubei ProvinceChina

AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout ***:Differential methylation profile was compared between normal bile duct epithelial cell lines and CCA cell lines by methyl-DNA immunoprecipitation (MeDIP)***-polymerase chain reaction (BSP)was performed to identify the methylated allels of target *** of target genes was investigated before and after the treatment with DNA demethylating *** of candidate genes was also evaluated by immunofluorescence in 30 specimens of CCA tissues and 9 normal bile duct ***:Methylation profile of CCA was identified with MeDIP microarray in the respects of different gene functions and signaling ***,97 genes with hypermethylated CpG islands in the promoter region were homeobox *** top 5 hypermethylated homeobox genes validated by BSP were HOXA2(94.29%),HOXA5(95.38%),HOXA11 (91.67%),HOXB4(90.56%)and HOXD13(94.38%).Expression of these genes was reactivated with 5’-aza2’-*** expression differences were found between normal bile duct and extrahepatic CCA tissues(66.67%-100%vs 3.33%-10%).CONCLUSION:HOXA2,HOXA5,HOXA11,HOXB4 and HOXD13 may work as differential epigenetic biomarkers between malignant and benign biliary tissues.

关键词： DNA methylation Epigenetic Promoter microarray Cholangiocarcinoma

Aggregation Processes with Catalysis-Driven Decomposition

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Communications in Theoretical Physics 2009年第10期52卷 622-626页

作者： XIANG Rong ZHUANG You-yi KE Jian-Hong LIN Zhen-quan School of Physics and Electronic Information Wenzhou University Wenzhou 325027 China

We propose a three-species aggregation model with catalysis-driven decomposition. Based on the mean-field rate equations, we investigate the evoIution behavior of the system with the size-dependent catalysis-driven decomposition rate J（i; j; k） = Jijk^v and the constant aggregation rates. The results show that the cluster size distribution of the species without decomposition can always obey the conventional scaling law in the case of 0 ≤v ≤ 1, while the kinetic evolution of the decomposed species depends crucially on the index v. Moreover, the total size of the species without decomposition can keep a nonzero value at large times, while the total size of the decomposed species decreases exponentially with time and vanishes finally.

关键词： decomposition kinetic behavior scaling law rate equation