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Identification of Contaminations Hiding Beneath the α- and β-Subunits of Partially Purified Nitrogenase MoFe Protein on the Sodium Dodecyl Sulfate Gel

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Journal of Integrative Plant Biology 2005年第11期47卷 1364-1371页

作者： Hui-Na ZHOU Ying ZHAO Shao-Min BIAN Jian-Feng ZHAO fei ren Huang-Ping WANG Ju-Fu HUANG Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China China Agricultural University Beijing 100094 China Fujian Normal University Fuzhou 350007 China

To identify the unknown proteins that would contaminate the α- and β-subunits of nitrogenase MoFe protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, the partially purified MoFe protein （Avl） preparation was obtained from Azotobacter vinelandii Lipmann OP by chroma- tography on DEAE-cellulose （DE52） and Sephacryl S-200 columns and analyzed by PAGE and matrix- assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry. The Av 1 preparation was shown to have two main bands at the position of the α- and β-subunits of crystalline Avl on the SDS gel. However, on the anoxic native PAGE, in addition to the Avl band, the preparation was shown to have three other main bands that migrated slower than Av 1. Of these three main bands, the protein with the fastest migration was identified as bacterioferritin elsewhere. The proteins on the other two bands, termed Upper and Middle, were suggested to be two different homopolymers with the same apparent subunit electrophoretic mobilities as the α- and β-subunits of Avl, respectively. By analysis of MALDI-TOF mass spectrometry, the Upper was identified as GroEL, which belongs to the heat shock protein 60 family, and the Middle was identified as glucose-6-phosphate isomerase （PGI）. In our preparation, anoxic native electrophoresis indicated that GroEL was composed of 14 identical subunits and that PGI was composed of 10 identical subunits. This is the first report of PGI, with so many subunits. The contaminating proteins in the Av 1 preparation, mainly GroEL and PGI, could be totally or partially removed from Av 1 if the shoulders and center of the elution peak were collected separately from the Sephacryl S-200 column and the center fraction was purified further by Q-Sepharose developed with an NaC1 concentration gradient. Thus, Avl with more than 90% purity was obtained. Obviously, this modified method is useful for the purification of mutant MoFe proteins with a high purity.

关键词： Azotobacter vinelandii chaperonin GroEL glucose-6-phosphate isomerase nitrogenase Av 1.

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关于全国高等中医药院校“十三五”规划教材《中医内科学》眩晕病若干问题的商榷

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中国中医药现代远程教育 2024年第3期22卷 182-185页

作者：刘飞祥林子璇任飞郭迎树张怀亮河南中医药大学第一附属医院脑病四病区河南郑州450046 河南省眩晕病诊疗中心河南郑州450046 河南省眩晕病研究所河南郑州450046 河南中医药大学第一附属医院互联网医院办公室河南郑州450046 河南中医药大学第一附属医院培训教育部河南郑州450046

全国高等中医药院校“十三五”规划教材《中医内科学》,自2012年将眩晕病从肝胆系病证分离并纳入脑系病证以来,条理更为清晰,取得了良好的教学效果。但经过多年的教学实践,“眩晕病”篇仍存在病名阐释不完整、诊断与辨治脱节、病因不完... 详细信息

全国高等中医药院校“十三五”规划教材《中医内科学》,自2012年将眩晕病从肝胆系病证分离并纳入脑系病证以来,条理更为清晰,取得了良好的教学效果。但经过多年的教学实践,“眩晕病”篇仍存在病名阐释不完整、诊断与辨治脱节、病因不完善、虚实分型难以指导临床、西医诊断不明确等一些值得讨论和商榷的问题,文章现对存在的问题进行探讨。

关键词：中医内科学眩晕头晕规范化

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Influence of thermo hydrogen treatment on microstructure and mechanical properties of Ti-5Al-2.5Sn ELI alloy

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China Foundry 2017年第1期14卷 55-58页

作者： Ya-fei ren Jun Zhao Hua-sheng Xie Shi-bing Liu Yan-chun Lou Ping Yan Shenyang Research Institute of Foundry Shenyang 110022China State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang 110022China Beijing Research Institute of Mechanical&Electrical Technology Beijing 100083China

Thermo hydrogen treatment （THT） of titanium is a process in which hydrogen is used as a temporary alloying element in titanium alloys. It is an attractive approach for controlling the microstructure and thereby improving the final mechanical properties. In the present study, the microstructure of the original （non-hydrogenated） sample has only a phase and the grains is coarse with an average size of - 650 pm. While the grain size of thermo hydrogen treated Ti-5Al-2.5Sn ELI alloy became finer and the mechanical properties were improved significantly. When the hydrogen content of the hydrogenated Ti-5Al-2.5Sn ELI alloy is 0.321wt.%, 13 phase and 6 titanium hydride appear. Also the average grain size decreases to 450 pm. When the hydrogen content is 0.515wt.%, the grain size decreases to 220μm. The mechanical properties were tested after dehydrogenation, and the mechanical properties improved significantly compared to the unhydrogenated specimens. The tensile strength of the Ti-5Al- 2.5Sn ELI alloy improved by 17.7% when the hydrogen content increased to 0.920wt.%, at the same time the percentage reduction of area （Z） increased by 33% and the impact toughness increased by 37%.

关键词： thermo hydrogen treatment microstructure mechanical properties

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基于Meta分析的北方草地植物功能性状对氮、磷添加的响应

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青海大学学报 2024年第4期42卷 19-25页

作者：崔靖陈梦娇何丰媛李兰平梁德飞任飞青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016 青海大学生态环境工程学院青海西宁810016 青海三江源草地生态系统国家野外科学观测研究站青海西宁810016

研究养分可利用性增加对功能性状的影响,有助于解析植物适应环境变化的机制。本研究基于Meta分析方法,探究氮、磷单独添加及耦合添加对北方草地植物地上-地下功能性状的影响。结果表明:氮、磷单独添加及耦合添加均显著增加植物的株高、... 详细信息

研究养分可利用性增加对功能性状的影响,有助于解析植物适应环境变化的机制。本研究基于Meta分析方法,探究氮、磷单独添加及耦合添加对北方草地植物地上-地下功能性状的影响。结果表明:氮、磷单独添加及耦合添加均显著增加植物的株高、叶面积、比叶面积、叶片氮含量和叶片磷含量,显著降低叶干物质含量。氮、磷单独添加及耦合添加均显著增加比根长、根系氮含量、根系磷含量和比根面积,显著降低根冠比和根直径。植物株高与叶面积、比叶面积、叶片氮含量、叶片磷含量呈显著正相关,与叶干物质含量呈显著负相关;根直径与比根长、比根面积、根冠比呈显著正相关,与根系氮含量和根系磷含量呈显著负相关;植物比叶面积与比根面积、根直径、根冠比呈正相关,表明氮、磷添加导致叶片与根系在资源获取和利用方面存在相对独立性。以上研究表明,北方草地植物地上-地下功能性状对氮、磷添加的响应表现并不完全一致,并且会改变叶片与根系的生物量分配。

关键词：北方草地氮、磷添加功能性状 Meta分析

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Duodenal-jejunal bypass reduces serum ceramides via inhibiting intestinal bile acid-farnesoid X receptor pathway

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World Journal of Gastroenterology 2022年第31期28卷 4328-4337页

作者： Zhi-Qiang Cheng Tong-Ming Liu Peng-fei ren Chang Chen Yan-Lei Wang Yong Dai Xiang Zhang Department of General Surgery Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Department of Colorectal and Anal Surgery Feicheng Hospital Affiliated to Shandong First Medical UniversityFeicheng 271600Shandong ProvinceChina Department of General Surgery Lincheng People’s HospitalDezhou 253500Shandong ProvinceChina

BACKGROUND Bile acids play an important role in the amelioration of type 2 diabetes following duodenal-jejunal bypass(DJB).Serum bile acids are elevated ***,the clinical relevance is not *** acids in the peripheral circulation reflect the amount of bile acids in the ***,a further investigation of luminal bile acids following DJB is of great *** To investigate changes of luminal bile acids following *** Salicylhydroxamic acid(SHAM),DJB,and DJB with oral chenodeoxycholic acid(CDCA)supplementation were performed in a high-fat-diet/streptozotocininduced diabetic rat *** weight,energy intake,oral glucose tolerance test,luminal bile acids,serum ceramides and intestinal ceramide synthesis were analyzed at week 12 *** Compared to SHAM,DJB achieved rapid and durable improvement in glucose tolerance and led to increased total luminal bile acid concentrations with preferentially increased proportion of farnesoid X receptor(FXR)-inhibitory bile acids within the common *** ceramide synthesis was repressed with decreased serum ceramides,and this phenomenon could be partially antagonized by luminal supplementation of FXR activating bile acid *** DJB significantly changes luminal bile acid composition with increased proportion FXR-inhibitory bile acids and reduces serum ceramide *** observations suggest a novel mechanism of bile acids in metabolic regulation after DJB.

关键词： Bariatric surgery Duodenal-jejunal bypass Farnesoid X receptor Ceramide Bile acids Liver fat accumulation

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Influence of Allele Frequency on Predicting Animal Phenotype Using Back-Propagation Artificial Neural Networks

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Wuhan University Journal of Natural Sciences 2011年第2期16卷 101-105页

作者： LI Xuebin YU Xiaoling GUO Yunrui XIANG Zhifeng ZHAO Kun ren fei College of Animal Science Henan Institute of Science andTechnology Xinxiang 453003 Henan China

To overcome the obstacle of the fascinating relation in predicting animal phenotype value, we have developed a neural network model to detect the complex non-linear relationships between the genotypes and phenotypes and the possible interactions that cannot be expressed with equations. In this paper, back-propagation neural network is used to discuss the influences of different allele frequencies on estimating the polygenic phenotype value. To ensure the precision of prediction, normalization was needed to train the prediction model. The results show that back-propagation artificial neural networks can be used to predict the phenotype value and perform very well in allele frequency from 0.2 to 0.8, when the allele frequency is very small （less than 0.2） or big （more than 0.8）; however, the prediction model was not reliable and the predicted value should be carefully tested.

关键词： artificial neural network single-nucleotide polymorphism (SNP) HapMap project genomic breeding value molecular marker allele frequency

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基于大数据分析的城市色彩调研及规划设计

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山西建筑 2024年第21期50卷 40-43页

作者：陈文竹郝峻弘朱鲁航李维昕任菲孙文玮南京市三江学院江苏南京210012

在城市更新背景下,文章以色彩地理学理论为基础,利用大数据和现代测色仪器,对宿迁市等9个城市的重点街区进行色彩采集,从城市自然环境、历史文脉、现状色彩角度开展综合分析,并进一步对宿迁市老城区建立新的色彩规划指导,提出从宏观到... 详细信息

在城市更新背景下,文章以色彩地理学理论为基础,利用大数据和现代测色仪器,对宿迁市等9个城市的重点街区进行色彩采集,从城市自然环境、历史文脉、现状色彩角度开展综合分析,并进一步对宿迁市老城区建立新的色彩规划指导,提出从宏观到微观的色彩管控建议、色彩规划方案等,以期为其他更新地区的城市建筑色彩规划提供参考。

关键词：城市色彩色彩规划色彩地理学

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H-NS Represses Biofilm Formation and c-di-GMP Synthesis in Vibrio parahaemolyticus

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Biomedical and Environmental Sciences 2022年第9期35卷 821-829页

作者： XUE Xing Fan ZHNAG Miao Miao SUN Jun Fang LI Xue WU Qi Min YIN Zhe YANG Wen Hui NI Bin HU Ling fei ZHOU Dong Sheng LU ren fei ZHANG Yi Quan School of Medicine Jiangsu UniversityZhenjiang 212013JiangsuChina Department of Clinical Laboratory Affiliated Nantong Hospital 3 of Nantong UniversityNantong 226006JiangsuChina State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijing 100071China

Objective This study aimed to investigate the regulation of histone-like nucleoid structuring protein(H-NS)on biofilm formation and cyclic diguanylate(c-di-GMP)synthesis in Vibrio parahaemolyticus *** Regulatory mechanisms were analyzed by the combined utilization of crystal violet staining,quantification of c-di-GMP,quantitative real-time polymerase chain reaction,LacZ fusion,and electrophoretic-mobility shift *** The deletion of hns enhanced the biofilm formation and intracellular c-di-GMP levels in *** RIMD2210633.H-NS can bind the upstream promoter-proximal DNA regions of scrA,scrG,VP0117,VPA0198,VPA1176,VP0699,and VP2979 to repress their *** genes encode a group of proteins with GGDEF and/or EAL domains associated with c-di-GMP *** One of the mechanisms by which H-NS represses the biofilm formation by *** RIMD2210633 may be via repression of the production of intracellular c-di-GMP.

关键词： Vibrio parahaemolyticus Biofilm H-NS C-di-GMP

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Spin-controlled generation of a complete polarization set with randomly-interleaved plasmonic metasurfaces

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Opto-Electronic Advances 2024年第8期7卷 16-24页

作者： Sören im Sande Yadong Deng Sergey I.Bozhevolnyi fei Ding Centre for Nano Optics University of Southern DenmarkOdense 5230Denmark

Optical metasurfaces,comprising subwavelength quasi-planar nanostructures,constitute a universal platform for manipulating the amplitude,phase,and polarization of light,thus paving a way for the next generation of highly integrated multifunctional optical *** this work,we introduce a reflective metasurface for the generation of a complete(angularly resolved)polarization set by randomly interleaving anisotropic plasmonic meta-atoms acting as nanoscale wave *** the proof-of-concept demonstration,we achieve multidirectional beam-steering into different polarization channels forming a complete set of polarization states,which can also be dynamically altered by switching the spin of incident *** developed design concept represents a significant advancement in achieving flat polarization optics with advanced functionalities.

关键词： plasmonic metasurface randomly interleaved multidirectional beam-steering spin-controlled all-polarization generation

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Phosphorus does not alleviate the negative effect of nitrogen enrichment on legume performance in an alpine grassland

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Journal of Plant Ecology 2017年第5期10卷 822-830页

作者： fei ren Weimin Song Litong Chen Zhaorong Mi Zhenhua Zhang Wenyan Zhu Huakun Zhou Guangmin Cao Jin-Sheng He Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of Sciences23 Xinning Rd.Xining 810008People’s Republic of China University of Chinese Academy of Sciences 19A Yuquan Rd.Beijing 100049China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University5 Yiheyuan Rd.Beijing 100871China

Aims Nitrogen(N)-fixing legumes,despite being highly phosphorus(P)-demanding,constitute an important plant functional group and play key roles in N-poor ecosystems such as alpine ***,legume performance,including biomass,abundance and species richness,is expected to change,because anthropogenic activities have drastically increased soil N and P availability *** conducted a field experiment to assess the effects of N and P addition,alone and in combination,on legume performance in an alpine grassland,and identified and clarified the mechanisms underlying these *** A three year field experiment of N addition(10 g N m−2 year−1),P addition(5 g P m−2 year−1),and N+P combined addition(both N and P,same amounts as solo treatments)was conducted in an alpine grassland on the tibetan Plateau in china from 2011 to *** of nutrient addition were assessed at the community level(above-ground net primary production(ANPP),height and light intensity),functional group level(biomass,species richness,relative height,relative coverage and relative density of legumes)and species level(foliar N,P concentration of two legumes).Important findings Overall,adding N alone significantly increased ANPP by 20.82%,but adding P alone did not;whereas,addition of N and P together resulted in a large increase in ANPP(+37.03%)than addition of either alone,indicating potential co-limitation of alpine *** contrast,adding P alone significantly promoted legume perfor-mance as measured by 65.22%increase in biomass and 58.45%increase in relative abundance,while adding N alone reduced leg-ume performance as measured by 39.54%decrease in biomass and 50.36%in relative *** P and N addition did not mitigate the negative effect of N addition on legume performance and,surprisingly,suppressed legume biomass by 53.14%and relative abundance by 63.51%.N and P addition altered the balance of light competition between grasses and legumes as indicated b

关键词： tibetan Plateau nutrient addition soil-nutrient interactions legume productivity species richness

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