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应用逐步回归方程求心血管系统的生物学年龄

天津医科大学学报 2001年第3期7卷 376-378页

作者：郭倩玉王佩显孙琪李晓春黄灿亮天津医科大学总医院心内科 300052

目的 :通过超声心动图 (UCG)检查测算心血管系统的生物学年龄。方法 :对320位高校健康教师行UCG检查 ,测量心血管系统结构及功能的多项指标。经相关分析筛选出老化指标,经多元回归分析建立心血管系统生物学年龄的回归方程。结果 :二尖... 详细信息

目的 :通过超声心动图 (UCG)检查测算心血管系统的生物学年龄。方法 :对320位高校健康教师行UCG检查 ,测量心血管系统结构及功能的多项指标。经相关分析筛选出老化指标,经多元回归分析建立心血管系统生物学年龄的回归方程。结果 :二尖瓣频谱E波的峰值速度与A波的峰值的比值 ,等容松弛时间 ,室间隔与主动脉根部的夹角 ,主动脉运动幅度是较敏感的老化指标 ,可进入多元回归方程。结论 :由超声参数可求出心血管系统生物学年龄的近似值。

关键词：心血管生物学年龄超声心动图多元回归方程

Compactly Supported Distributional Solutions of Nonstationary Nonhomogeneous Refinement Equations

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Acta Mathematica Sinica,English Series 2001年第1期17卷 1-14页

作者： Qi yu sun Department of Mathematics National University of Singapore

Let A be a matrix with the absolute values of all eigenvalues strictly larger than one, and let Z0 be a subset of Z such that n∈Z0 implies n+1∈Z0. Denote the space of all compactly supported distributions by D’, and the usual convolution between two compactly supported distributions f and g by f*g. For any bounded sequence Gn and Hn, n∈Z0, in D’, define the corresponding nonstationary nonhomogeneous refinement equation Φn=Hn*Φn+1（A.）+Gn for all n∈Z0, （*） where Φn, n∈Z0, is in a bounded set of D’. The nonstationary nonhomogeneous refinement equation （*） arises in the construction of wavelets on bounded domain, multiwavelets, and of biorthogonal wavelets on nonuniform meshes. In this paper, we study the existence problem of compactly supported distributional solutions Φn, n∈Z0, of the equation （*）. In fact, we reduce the existence problem to finding a bounded solution Fn of the linear equations n-Sn n+1= n for all n∈Z0, where the matrices Sn and the vectors n, n∈Z0, can be constructed explicitly from Hn and Gn respectively. The results above are still new even for stationary nonhomogeneous refinement equations.

关键词： Nonhomogeneous refinement equation Nonstationary refinement equation Colltinuous refinement equation Refinement equation Wavelets

Catalytic Oxidation of NO over La_(0.8)Sr_(0.2)MnO_3 Perovskite

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Chemical Research in Chinese Universities 2008年第5期24卷 620-627页

作者： ZHAO Ying-xian WEI Feng yu Ying Ningbo Institute of Technology Zhejiang University Ningbo 315100 P. R. China

Catalytic oxidation of NO by O2 over La0.8Sr0.2MnO3 was tested in a tubular *** reaction temperature ranged from 373 to 473 K,space time from 0.090 to 0.720 s,inlet NO concentration from 300 to 2000μL/L, and O2 volume fraction from 3%to 9%.The steady-state conversion of NO was increased significantly with increasing reaction temperature and the space time,slightly with increasing the O2 concentration but decreased with increasing the inlet NO concentration at a lower *** the conditions of 0.720 s space time,500μL/L NO concentration, 5%O2 volume fraction and 473 K,NO conversion reached 90%.A kinetic model including a network of 12 elementary reactions with the desorption of NO2 as the rate-limiting step is established and fits the experimental data *** activation energy of NO2 desorption from the catalyst surface is determined to be 101 kJ/mol.

关键词： Catalytic oxidation Nitric oxide La0.8Sr0.2MnO3 catalyst Kinetics

Recent advances in the research for the homolog of breast cancer associated gene AtROW1 in higher plants

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Science China(Life Sciences) 2016年第8期59卷 825-831页

作者： yue Jiao yuzhou Zhang yu-xian Zhu State Key Laboratory of Protein and Plant Gene Research College of Life Sciences Peking University Center for Science and Technology Development Ministry of Agriculture

BARD1(BRCA1 associated RING domain protein 1), as an important animal tumor suppressor gene associated with many kinds of cancers, has been intensively studied for decades. Surprisingly, homolog of BARD1 was found in plants and it was renamed At ROW1(repressor of Wuschel-1) according to its extremely important function with regard to plant stem cell homeostasis. Although great advances have been made in human BARD1, the function of this animal tumor-suppressor like gene in plant is not well studied and need to be further elucidated. Here, we review and summarize past and present work regarding this protein. Apart from its previously proposed role in DNA repair, recently it is found essential for shoot and root stem cell development and differentiation in plants. The study of At ROW1 in plant may provide an ideal model for further elucidating the functional mechanism of BARD1 in mammals.

关键词： repressor of Wuschel-1 DNA repair stem cell niche

Single-Nucleotide Resolution Mapping of the Gossypium raimondii Transcriptome Reveals a New Mechanism for Alternative Splicing of Introns

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Molecular Plant 2014年第5期7卷 829-840页

作者： Qin Li Guanghui Xiao yu-xian Zhu State Key Laboratory of Protein and Plant Gene Research College of Life Sciences Peking University Beijing 100871 China National Center for Plant Gene Research (Beijing) Beijing 100101 China

Alternative splicing （AS） is a vital genetic mechanism that enhances the diversity of eukaryotic transcriptomes. Here, we generated 8.3 Gb high-quality RNA-sequencing data from cotton （Gossypium raimondii） and performed a systematic, comparative analysis of AS events. We mapped 85% of the RNA-sequencing data onto the reference genome and identified 154 368 splice junctions with 16 437 as events in 10197 genes. I ntron retention constituted the majority （40%） of all AS events in G. raimondii. Comparison across 11 eukaryote species showed that intron retention is the most common AS type in higher plants. Although transposable elements （TEs） were found in only 2.9% of all G. raimondii introns, they are present in 43% of the retained introns, suggesting that TE-insertion may be an important mechanism for intron retention during AS. The majority of the TE insertions are concentrated 0-40 nt upstream of the 3＇-splice site, substantially altering the distribution of branch points from preferred positions and reducing the efficiency of intron splicing by decreasing RNA secondary structure flexibility. Our data suggest that TE-insertion-induced changes in branch point-site distribution are important for intron retention-type AS. Our findings may help explain the vast differences in intron-retention frequencies between vertebrates and higher plants.

关键词： cotton RNA-seq alternative splicing transposable element intron retention.

Novel HBV mutations and their value in predicting efficacy of conventional interferon

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Hepatobiliary & Pancreatic Diseases International 2017年第2期16卷 189-196页

作者： Da-xian Wu Xiao-yu Fu Guo-Zhong Gong Ke-Wei sun Huan-yu Gong Ling Wang Juan Wu De-Ming Tan Department of Infectious Diseases Xiangya Hospital Central South University Key Laboratory of Viral Hepatitis of Hunan Province Department of Infectious Diseases The Second Xiangya Hospital Central South University Department of Infectious Diseases The First Affiliated Hospital Hunan University of Chinese Medicine Department of Infectious Diseases The Third Xiangya Hospital Central South University

BACKGROUND： Accumulating studies assessing the impacts of hot spot mutations on conventional interferon（IFN） efficacy come to discrepant conclusions; studies regarding the mutations in S and RT regions are also unclear. The present study aimed to evaluate the impacts of HBV mutations on the efficacy of conventional IFN. METHODS： A total of 126 patients who received conventional IFN treatment for 48 weeks were enrolled. Biochemical and serological parameters were routinely tested. The sequences of HBV from 78 serum samples were amplified by nested-PCR; mutations were identified with sequence scanner V1.0 after ABI 3730 xl direct sequencing, HBV genotypes were determined according to RT gene sequences utilizing NCBI Genotyping Tool which was based on phylogenetic ***： The baseline DNA levels of virological response（VR） group were significantly lower than those of no VR group [7.13±0.76 vs 7.69±0.56 lg（copies/m L）, P=0.001]. The baseline ALT levels were significantly higher in the HBe Ag clearance group（204.72±88.65 vs 162.80±85.81 IU/L, P〈0.05） andHBe Ag seroconversion group（204.89 ±95.68 vs 166.75±84.43 IU/L, P〈0.05）. Females and lower BMI levels（20.01±2.33 vs 21.65±3.66 kg/m^2, P〈0.05） were prone to acquired biochemical response（BR）. PC-W28STOP（ntG 1896A） was significantly higher in the combined response（CR） group than that in the no CR group（91.7% vs 39.7%, P=0.001）. Multivariate logistic regression analysis showed that baseline DNA, PC-P159T（ntC2288A）, BCP-N118T（ntA 1726C） and BCP-L134L（ntA 1775C/G/T） influenced VR independently. PC-G182C（nt G2357T）, PC-S64A/T（nt T2003G/A） and BMI were independent influence factors for HBe Ag clearance, HBe Ag seroconversion and BR, respectively. The new predicting model concluded that baseline DNA and new mutations for VR were established successfully, and ROC analysis showed that AUC was 0.842（P〈0.001） with a sensitivity of 0.652 and a specificity of ***： PC-P159T（ntC 2288A）, BCP-N118T（ntA 1726C）, BCP-

关键词： hepatitis B virus interferon mutation treatment efficacy

Identification and Analyses of miRNA Genes in Allotetraploid Gossypium hirsutum Fiber Cells Based on the Sequenced Diploid *** Genome

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Journal of Genetics and Genomics 2012年第7期39卷 351-360页

作者： Qin Li xiang Jin yu-xian Zhu The State Key Laboratory of Protein and Plant Gene Research College of Life SciencesPeking UniversityBeijing 100871China National Center for Plant Gene Research(Beijing) Beijing 100101China

The plant genome possesses a large number of microRNAs （miRNAs） mainly 21-24 nucleotides in length. They play a vital role in regulation of target gene expression at various stages throughout the whole plant life cycle. Here we sequenced and analyzed ~ 10 million non-coding RNAs （ncRNAs） derived from fiber tissue of the allotetraploid cotton （Gossypium hirsutum） 7 days post-anthesis using ncRNA-seq technology. In terms of distinct reads, 24 nt ncRNA is by far the dominant species, followed by 21 nt and 23 nt ncRNAs. Using ab initio prediction, we identified and characterized a total of 562 candidate miRNA gene loci on the recently assembled D5 genome of the diploid cotton G. raimondii. Of all the 562 predicted miRNAs, 22 were previously discovered in cotton species and 187 had sequence conservation and homology to homologous miRNAs of other plant species. Nucleotide bias analysis showed that the 9th and 1st positions were significantly conserved among different types of miRNA genes. Among the 463 putative miRNA target genes, most significant up/down-regulation occurred in 10-20 days post-anthesis, indicating that miRNAs played an important role during the elongation and secondary cell wall synthesis stages of cotton fiber development. The discovery of new miRNA genes will help understand the mechanisms of miRNA generation and regulation in cotton.

关键词： Cotton Genome Micro RNA Deep sequencing Microarray

Caustic Failure of Thermal Insulated Tubing in Steam Flooding

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Journal of Materials Science & Technology 1997年第1期13卷 27-36页

作者： xian, AP San, YY Zhang, D Wang, YK sun, HP LIAOHE OIL FIELD MACHINERY PLANT PANJIN 124209PEOPLES R CHINA

The coupling of the pre-stressed thermal insulated tubing string broke down inside the steam flooding welts, after the tubing were used in high temperature and high pressure steam for about two years. With further check, it was found that most of the weld joints between the inner and outer tubing also cracked. The failure analysis for the accidents has been carried out by the analysis of chemical composition for the steels, microstructure observation, mechanical property tests, and the investigation of the service environment etc.. The results show that the early damage of the pre-stressed thermal insulated tubing string is mainly induced by the caustic stress corrosion, which can be strengthened by an unstable microstructure of the coupling serviced at high temperature for a long time. Moreover, the high pre-stress design on the thermal insulated pipe for the cyclic steam injection may be not suitable to the situation of steam flooding, which would result in the weld joint cracking.

关键词： Steel pipe

The Study of Group Scheduling Problems with General Dual-Position-Based Job Processing Times

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Journal of the Operations Research Society of China 2017年第4期5卷 509-527页

作者： xian-yu yu De-Qun Zhou yu-Lin Zhang College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Economics and Management Southeast UniversityNanjing 210096China

Scheduling with group technology has been a vivid research area in the past ***,group technology with general dual-effect variable processing times needs to be further explored although this kind of group technology plays an important role in some actual manufacturing ***,this paper considers group scheduling problems with a kind of general group variable processing times model,where the actual processing time of each job in group is variable due to the dual effect of both the job position and the group *** objectives of two types of considered problems are to minimize the makespan and the total completion time,*** on the decomposition analysis,the mathematical logic analysis and the computational complexity proof,it is obtained that the makespan minimization problem and the total completion time minimization problem are both polynomially solvable under the condition that the group number is *** three special cases of considered problems,polynomial solving algorithms with lower computational complexity are proposed.

关键词： Group scheduling Single machine Dual position based Computational analysis