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Learning from regularized regression algorithms with p-order Markov chain sampling

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 295-306页

作者： ZHANG Jing wang Jian-li sheng Bao-huai Department of Mathematics Shaoxing College of Arts and Sciences Shaoxing 312000 China.

Evaluation for the performance of learning algorithm has been the main thread of theoretical research of machine learning. The performance of the regularized regression algorithm based on independent and identically distributed（i.i.d.） samples has been researched by a large number of references. In the present paper we provide the convergence rates for the performance of regularized regression based on the inputs of p-order Markov chains.

关键词： p-order Markov chain uniformly ergodic learning rate.

The Mining of Citrus EST-SNP and Its Application in Cultivar Discrimination

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Agricultural Sciences in China 2010年第2期9卷 179-190页

作者： JIANG Dong YE Qing-liang wang Fu-sheng CAO li Citrus Research Institute Chinese Academy of Agricultural Sciences Chongqing 400712 P.R.China

Single nucleotide polymorphisms （SNPs） are the most abundant sequence variations found in plant genomes and are widely used as molecular genetic markers in cultivar identification and genetic diversity studies. The objective of this study was to identify SNP markers useful for discrimination of citrus cultivars, since large numbers of expressed sequence tags （ESTs） of sweet orange are available from the National Center for Biotechnology Information （NCBI）. We now have the opportunity to discover SNP markers suitable for determining the haplotypes with which to distinguish very closely related cultivars and to assess genetic diversity within or between related species of citrus. SNPs and small insertions/deletions （Indels） from ESTs of sweet orange and satsuma were identified by the in silico SNP discovery strategy. 55 296 EST sequences of sweet orange and 2 575 of satsuma retrieved from the NCBI repository were mined for potential SNPs. Cleaved amplified polymorphic sequences （CAPS） and sequencing approaches were used to validate putative SNPs in a sample of 30 citrus accessions. A total of 3 348 putative SNPs were identified based on the abundance of sequences and haplotype cosegregation. Of these 3 348 SNPs, the transitions, transversions and Indels ratios were 47.9, 36.1 and 16.0%, respectively. The SNPs occurred on average at a frequency of 1 per 164 bp in the coding region of citrus. 14 SNPs were randomly selected and genotyped according to 30 citrus accessions including 23 accessions of sweet orange; 11 SNPs displayed polymorphism with an average polymorphism information content （PIC） of 0.20 among 30 citrus accessions. The genetic diversity present in sweet orange was low, so the 14 SNP markers failed to discriminate different cultivars of sweet orange, but they did succeed in distinguishing accessions of inter-species of citrus. In this study, SNPs were mined from EST sequences of sweet orange and satsuma, which displayed potential capability as molecular ma

关键词： citrus single nucleotide polymorphisms (SNPs) EST-SNP cleaved amplified polymorphic sequences (CAPS)

Xishaglaucumins A—J,New Cembranoids with Anti-Inflammatory Activities from the South China Sea Soft Coral Sarcophyton glaucum

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Chinese Journal of Chemistry 2022年第1期40卷 79-90页

作者： Jin-Feng li Yan-Bo Zeng wang-sheng li Hui Luo Hai-Yan Zhang Yue-Wei Guo Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikouHainan 571101China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zu Chong Zhi RoadZhangjiang Hi-Tech ParkShanghai 201203China Ocean College of Hebei Agricultural University QinhuangdaoHebei 066000China Key Laboratory of Zhanjiang for Research and Development Marine Microbial Resources in the Beibu Guif Rim Marine Biomedical Research InstituteGuangdong Medical UniversityZhanjiangGuangdong 524023China Bohai rim Advanced Research Institute for Drug Discovery YantaiShandong 264000China

Ten new cembrane-type diterpenoids,namely xishaglaucumins A—J(1—10),along with ten known related ones(11—20),have been isolated from the soft coral Sarcophyton glaucum collected off the Xisha Island in the South China *** structures were elucidated by extensive spectroscopic analysis,quantum mechanical nuclear magnetic resonance(QM-NMR)methods,X-ray diffraction analysis,chemical methods and comparison with the reported data in the *** absolute configuration of new compounds 1,5 and known compounds 11,12,16 and 20 were determined either by chemical methods or by X-ray diffraction analysis using Cu Kα(λ=1.5417A).In in vitro bioassay,compound 4 exhibited inhibitory effects on lipopolysaccharide(LPS)-induced inflammatory responses in BV-2 microglial cells.

关键词： Sarcophyton glaucum Cembranoids Configuration determination X-ray diffraction NMR spectroscopy

Three New Silver Alkylenediphosphonates with Pillar-like Open-frameworks

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1231-1241页

作者： FU Rui-Biao HU sheng-Min ZHANG Hui-Shuang wang Long-sheng li Ya-Min HUANG Xi-He WU Xin-Tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Science Fuzhou Fujian 350002 China

Three new silver alkylenediphosphonates, [Ag2（HO3PCH2CH2CH2CH2PO3H）] 1, [Ag4（O3PCH2CH2CH2CH2PO3）] 2 and [Ag4（O3PCH2CH2CH2PO3（H2O）] 3, have been hydrotherreally synthesized and characterized by X-ray single-crystal and powder diffraction, elemental analyses, IR and thermogravimetric analyses （TGA）. The structures of these compounds are all threedimensional pillar-like open-frameworks with 18-membered [Ag2O4P4C8] channels for compound 1 and 2, and 16-member [Ag2O4P4C6] channels for compound 3. Both 2 and 3 contain interesting twodimensional Ag（Ⅰ） networks based on Ag...Ag interactions. 1,4-Butylene- and 1,3-propylene diphosphonate groups of 2 and 3 bond the first and second maximum metal atoms among metal organodiphosphonates with linking sixteen and fifteen silver（Ⅰ） atoms, respectively. In addition, the coordinated water molecules of 3 can be reversibly removed and recovered.

关键词： hydrothermal syntheses silver diphosphonate pillar-like single crystal

Warm Deformation Behavior of Steels Containing Carbon of 0.45% to 1.26% With Martensite Starting Structure

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Journal of Iron and Steel Research International 2010年第5期17卷 34-37页

作者： li Qun wang Tian-sheng li Hong-biao GAO Yu-wei liNing JING Tian-fu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004 Hebei China

Warm deformation was investigated for steels containing carbon of 0. 45%,0. 79%, and 1. 26% respeetively with martensite starting structure, using Gleeble 3500 thermomechanical simulator at the temperature ranging from 873 K to 973 K and the strain rate ranging from 0.1 s^-1 to 0. 001 s^-1. The effect of carbon content on the deformation activation energy, Z value and the deformation resistance was analyzed, The results showed that the deformation resistance decreased with increasing carbon content. The peak stress of the steel containing earbon of 1.26% was decreased by 16.2% compared to the steel containing carbon of 0.45% under the same condition. This may be attributed to the weakening effect of solid solution strengthening which outweighs the precipitation strengthening of cementite.

关键词： carbon steel martensite starting structure warm deformation deformation resistance

ViWoSG:A distributed scene graph of ultra-massive distributed virtual environments

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Science in China(Series F) 2009年第3期52卷 457-469页

作者： wang GuoPing, li sheng, wang ShaoRong, LU Bin & li WenHang Key Lab of Machine Perception and Intelligent, MOE Department of Computer Science, Peking University, Beijing 100871, China Key Lab of Machine Perception and Intelligent MOE Beijing China Department of Computer Science Peking University Beijing 100871 China

An ultra-massive distributed virtual environment generally consists of ultra-massive terrain data and a large quantity of objects and their attribute data, such as 2D/3D geometric models, audio/video, images, vectors, characteristics, etc. In this paper, we propose a novel method for constructing distributed scene graphs with high extensibility. This method can support high concurrent interaction of clients and implement various tasks such as editing, querying, accessing and motion controlling. Some application experiments are performed to demonstrate its efficiency and soundness.

关键词： VR distributed system scene graph ultra-massive distributed scene graph

Request-Refusal Strategies in Contemporary Chinese Teledramas From the Perspective of Social Power

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Sino-US English Teaching 2011年第7期8卷 425-436页

作者： wang sheng-li Henan Agricultural University Zhengzhou China

This study was designed to explore the issue of request-refusal strategies in Chinese setting by establishing a corpus of vedio clips of contemporary Chinese teledramas on the basis of an overview of previous studies on Chinese refusal strategies. In the present study, we chose 3,970 short sequences of video clips from 35 Chinese teledramas which vividly described the Chinese people＇s life in the contemporary times. Taking the two variables of power and distance as reference points, nine situations were designed in this study. Elaborate refusal strategies were consecutively elicited in the nine situations of the 35 contemporary Chinese teledrama serials from the perspective of social power in the study.

关键词： request refusal strategies social power Chinese teledramas

Effect of Nitrogen Applied Before Transplanting on NUE in Rice

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Agricultural Sciences in China 2007年第7期6卷 842-848页

作者： ZHENG Yong-mei DING Yan-feng wang Qiang-sheng li Gang-hua WU Hao YUAN Qi wang Hui-zhi wang Shao-hua Key Laboratory of Crop Growth Regulation Ministry of Agriculture/Nanjing Agricultural University Nanjing 210095 P.R.China

Nitrogen （N） application before transplanting, where N fertilizers are applied in seedling-bed and carried to the paddy field with seedlings, is a novel method proposed in this article aiming for improving nitrogen utilization efficiency （NUE） in rice. The effect of this method on mineral N distribution in the rhizosphere soil was investigated in a field experiment with a japonica variety, Ningjing 2, in seasons of 2004 and 2005. There were four levels of N applied 16 h before transplanting： zero N （NO）, 207 kg ha^-1 （NL）, 310.5 kg ha^-1 （NM）, and 414 kg ha^-1 （NH）. The result indicated that N fertilizer before transplantation had positive effect of increasing mineral N content in the rhizosphere soil of rice. Generally, N content in the rhizosphere soil of rice tended to increase with the amount of N fertilizer before transplanting, with the NH treatment having the largest effect. Additionally, N fertilizer before transplanting had significant influence on rice NUE and grain yield. Compared with other treatments, the NM treatment showed the largest influence, with basal-tillering NUE, total NUE, and grain yield being 15%, 12%, and 529.5 kg ha^-1 higher than those of NO treatment. This result indicated that N fertilizer before transplantation had positive effect on mineral N distribution in the rhizosphere soil of rice, thus improving NUE and grain yield.

关键词： rice nitrogen (N) application before transplanting nitrogen utilization efficiency (NUE) grain yield

Titanium mesh fusion device in the treatment of thoracolumbar burst fracture

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Chinese Medical Journal 2007年第3期120卷 246-247页

作者： wang Yi-sheng YIN li BAO Heng wang Wei-dong Department of Orthopedics First Affiliated Hospital of Zhengzhou University. Zhengzhou 450052 China

Thoracolumbar burst fracture, a common condition in clinic, often leads to severe spinal instability and neurologic deficit. In most cases, the compression that caused by backward protrusion of the fracture fragments to the spinal cord, makes complete decompression difficult through a posterior approach. Here, we reviewed the clinical records of 22 patients with thoracolumbar burst fracture treated by anterior corpectomy, decompression of the spinal cord, and implantation of titanium mesh cage.

关键词： thoracolumbar burst fracture titanium mesh fusion divice surgery