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Seasonal changes of organic matter origins and anammox activity in the Changjiang Estuary deduced from multi-biomarkers in suspended particulates

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Science China Earth Sciences 2016年第7期59卷 1339-1352页

作者： hu jing wen ZHANG Hai Long LI Li WANG Yao Yao ZHAO Mei Xun Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China

human activity-induced eutrophication and harmful algal blooms are main causes of the expansion of the hypoxic zone in the Changjiang Estuary. Among the many changes in biogeochemical processes, anaerobic ammonium oxidation(anammox) is proposed to play an important role in the nitrogen cycle in hypoxic areas. Ladderane lipids have been used as biomarkers to indicate anammox activity in ecosystems, but the origins of anammox bacteria and ladderanes in suspended particulates are still unclear. In this study, we report the results of a suite of biomarker analyses of suspended particulates across a salinity gradient of the Changjiang Estuary in both the spring and summer to evaluate the origins of the ladderanes and their potential as proxies for anammox activity and hypoxia. The spatio-temporal variations in terrestrial biomarkers(n-alkanes and n-alkanols), marine biomarkers(brassicasterol and dinosterol), and the Terrestrial and Marine Biomarker Ratio and Branched and Isoprenoid Tetraether indices reveal that marine organic matter was dominant in the particulates in both the spring(55%) and summer(86%) seasons. Correlations with both marine and terrestrial biomarkers suggest that ladderanes were mainly produced in the water column, and therefore that ladderane concentrations in suspended particulates in the Changjiang Estuary mainly reflect anammox activity in the water column, although changes in anammox bacterial assemblages may also have played a role in ladderane concentrations. Overall, ladderane results suggest that anammox activity was widespread in the Changjiang Estuary; but higher ladderane concentrations in the summer(especially in the upwelling zone) were correlated with lower dissolved oxygen concentrations, which suggest that they are useful proxies for hypoxia.

关键词： Changjiang Estuary Particulates Biomarkers Ladderane Anammox Hypoxia

Marker-assisted selection to pyramid Fusarium head blight resistance loci Fhb1 and Fhb2 in the high-quality soft wheat cultivar Yangmai 15

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Journal of Integrative Agriculture 2023年第2期22卷 360-370页

作者： hu wen-jing FU Lu-ping GAO De-rong LI Dong-sheng LIAO Sen LU Cheng-bin Key Laboratory of Wheat Biology and Genetic Improvement for Low&Middle Yangtze Valley Ministry of Agriculture and Rural AffairsLixiahe Institute of Agricultural SciencesYangzhou 225007P.R.China College of Agronomy&Center for Crop Genome Engineering Henan Agricultural UniversityZhengzhou 45002P.R.China Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College Yangzhou UniversityYangzhou 225009P.R.China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China College of Agriculture Yangtze UniversityJingzhou 434023P.R.China

Fusarium head blight(FHB)is one of the most detrimental wheat diseases which greatly decreases the yield and grain quality,especially in the middle and lower reaches of the Yangtze River of ***1 and Fhb2 are two major resistance loci against Fusarium *** 15(YM15)is one of the most popular varieties in the middle and lower reaches of the Yangtze River,and it has good weak gluten characters but poor resistance to *** we used Fhb1 and Fhb2 to improve the FHB resistance of YM15 by a molecular marker-assisted selection(MAS)backcrossing *** selection of agronomic traits was performed for each *** successfully selected seven introgressed lines which carry homozygous Fhb1 and Fhb2 with significantly higher FHB resistance than the recurrent parent *** of the introgressed lines had agronomic and quality characters that were similar to *** study demonstrates that the pyramiding of Fhb1 and Fhb2 could significantly improve the FHB resistance in wheat using the MAS approach.

关键词： Fusarium head blight marker-assisted selection Fhb1 Fhb2 resistance breeding wheat

Synthesis and Water Uptake of Sulfonated Poly (phthalazinone ether sulfone ketone)/Polyacrylic Acid Proton Exchange Membranes

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Chinese Chemical Letters 2006年第7期17卷 965-968页

作者： Xue Mei WU Gao Hong HE Lin GAO Shuang GU Zheng wen hu Ping jing YAO State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

Novel SPPESK/PAA composite proton exchange membranes with semi-interpenetrating polymer network （sIPN） structure have been synthesized through the in-situ polymerization of acrylic acid （AA） in the presence of sulfonated poly （phthalazinone ether sulfone ketone）（SPPESK）. The composite membranes were identified by FT-IR analysis. Water uptake of the composite membranes was as high as 89.7% at 90℃, nearly one time higher than that of the corresponding SPPESK membrane.

关键词： Proton exchange membranes interpenetrating polymer network in-situ polymerization.

Molecular Cloning and Characterization of an Allene Oxide Cyclase Gene Associated with Fiber Strength in Cotton

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Journal of Integrative Agriculture 2014年第10期13卷 2113-2121页

作者： WANG Li-man Zhu You-min TONG Xiang-chao hu wen-jing CAI Cai-ping GUO Wang-zhen State Key Laboratory of Crop Genetics & Germplasm Enhancement Hybrid Cotton R&D Engineering Research CenterMinistry of Education/College of AgricultureNanjing Agricultural University

Allene oxide cyclase （AOC） is one of the most important enzymes in the biosynthetic pathway of the plant hormone jasmonic acid （JA）. AOC catalyzes the conversion ofallene oxide into 12-oxo-phytodienoic acid （OPDA）, a precursor of JA. Using 28K cotton genome array hybridization, an expressed sequence tag （EST; GenBank accession no. ES792958） was investigated that exhibited significant expression differences between lintless-fuzzless XinWX and linted-fuzzless XinFLM isogenic lines during fiber initiation stages. The EST was used to search the Gossypium EST database （http：//***/） for corresponding cDNA sequences encoding full-length open reading frames （ORFs）. Identified ORFs were confirmed using transcriptional and genomic data. As a result, a novel gene encoding AOC in cotton （Gossypium hirsutum AOC; GenBank accession no. KF383427） was cloned and characterized. The 741-bp GhAOC gene comprises three exons and two introns and encodes a polypeptide of 246 amino acids. Two homologous copies were identified in the tetraploid cotton species G. hirsutum acc. TM-1 and G. barbadense cv. Hai7124, and one copy in the diploid cotton species G. herbaceum and G. raimondii, qRT-PCR showed that the GhAOC transcript was abundant in cotton fiber tissues from 8 to 23 days post anthesis （DPA）, and the expression profiles were similar in the two cultivated tetraploid cotton species G. hirsutum acc. TM- 1 and G. barbadense cv. Hai7124, with a higher level of transcription in the former. One copy of GhAOC in tetraploid cotton was localized to chromosome 24 （Chr. D8） using the subgenome-specific single nucleotide polymorphism （SNP） marker analysis, which co-localized GhAOC to within 10 cM of a fiber strength quantitative trait locus （QTL） reported previously. GhAOC was highly correlated with fiber quality and strength （P=0.014） in an association analysis, suggesting a possible role in cotton fiber development, especially in secondary cell wall thickening.

关键词： allene oxide cyclase structure expression pattern fiber development association analysis cotton

基于BP神经网络的表面偏斜度和峰度预测建模

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表面技术 2017年第2期46卷 235-239页

作者：胡敬文佛山广播电视大学广东佛山528000

目的当前实际生产中对表面形貌的表征主要利用表面算术平均偏差Sa,而通过不同加工方式获得的表面有时尽管具有相同的Sa值,而其表面纹理结构、表面轮廓幅度值的对称程度及凸峰尖锐程度往往存在较大的差异,所以此时引入表面偏斜度Ssk和表... 详细信息

目的当前实际生产中对表面形貌的表征主要利用表面算术平均偏差Sa,而通过不同加工方式获得的表面有时尽管具有相同的Sa值,而其表面纹理结构、表面轮廓幅度值的对称程度及凸峰尖锐程度往往存在较大的差异,所以此时引入表面偏斜度Ssk和表面峰度Sku来共同表征表面形貌更为精确可信。方法利用正交试验和极差分析的方法研究各磨削参数如何影响表面偏斜度和表面峰度的变化。将BP神经网络引入到对表面偏斜度和表面峰度的预测建模中,利用其自学习的特性,有效克服了表面粗糙度建模的多输入、非线性复杂问题。结果获得了磨削参数对表面偏斜度和表面峰度的影响规律,当v_s=20 m/s,v_f=27 m/min,f=5mm/min,ap=0.005 mm时Ssk最小,当v_s=29 m/s,v_f=23 m/min,f=25 mm/min,ap=0.002 mm时S_(ku)最小;分别建立了磨削参数对S_(sk)和S_(ku)的精确神经网络预测模型。结论 v_f和f对S_(sk)影响较大,而f和vs对Sku的影响最大。为获得凹谷较多、尖锐凸峰较少的表面,必须选择合适的磨削工艺参数。建立的预测模型可以对磨削工艺优化起到有效的指导作用。

关键词：表面偏斜度表面峰度磨削参数神经网络预测建模

The Studies of Composite Electroless Plating Process on Sintering Ndfeb Permanent Magnet

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材料热处理学报 2004年第05B期25卷 1112-1114页

作者： huJian-wen MAjing YANDong-qing GAOQing MENGYong-qiang Schoolofmaterial HebeiUniversityofScienceandTechnologyShijiazhuangChina

A reasonable pre-treatment and an ultrasonic pre-plating Cu film were applied for sintering NdFeB permanent magnet. The samples were then plated in neutral bath (PH=7) for 40min and in acidic bath (PH=4.8～5.1) for 2h. A composite electroless plating with different phosphor content was obtained. The results show that the composite plating coatings are dense and have a strong bond with the substrate, which contribute to the excellent corrosion resistance of the plating coating.

关键词： NdFeB永久磁铁预处理无电极电镀耐蚀性

Molecular and Cytogenetic Characterization of a Fetus with Mosaic Ring Chromosome 13： A Very Rare Case

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Chinese Medical Journal 2017年第24期130卷 3007-3008页

作者： Xin-Rong Zhao Xu Han Yan-Lin Wang wen-jing hu Department of Prenatal Diagnostic Center The International Peace Maternity and Child Health Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200030 China Department of Reproductive and Genetic The International Peace Maternity and Child Health Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200030 China

The major mechanism for ring chromosome formation is thought to result from breakage and reunion at the breakpoints on the long and short arms of a *** fusion event can produce terminal arm inversions,deletions,and duplications that determine the resulting phenotype.[1] Ring chromosome 13 is relatively uncommon,with an estimated incidence of 1/58,000 live births.

关键词： Array-based Comparative Genomic Hybridization Mosaicism

具有三角架结构的丙二酸、β-二酮和吡唑衍生物的合成、结构及超分子自组装

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高等学校化学学报 2011年第9期32卷 2145-2151页

作者：胡聪马明亮李晓燕胡文敬赵小莉文珂华东师范大学脑功能基因组学教育部重点实验室超分子化学与药物化学研究室上海200062 华东师范大学化学系上海市绿色化学与化工过程绿色化重点实验室上海200062 中国科学院上海高等研究院纳米中心上海201203

合成了几个1,3,5-三乙基衍生物,它们分别含有丙二酸取代基(2～5)、戊烷-2,4-二酮取代基(6)和3,5-二甲基-1H-吡唑取代基(7),并对上述衍生物的结构进行了表征.1H NMR分析表明,这些化合物在溶液中具有高度对称性;X射线单晶衍射分析确认上... 详细信息

合成了几个1,3,5-三乙基衍生物,它们分别含有丙二酸取代基(2～5)、戊烷-2,4-二酮取代基(6)和3,5-二甲基-1H-吡唑取代基(7),并对上述衍生物的结构进行了表征.1H NMR分析表明,这些化合物在溶液中具有高度对称性;X射线单晶衍射分析确认上述化合物在固态时均采取1,3,5-交替构象,即3个功能取代基团处在中心苯环平面的一边,3个乙基则位于该中心苯环平面的另一边.分子内和分子间氢键是化合物4,5及7实现超分子自组装的主要作用力.化合物7(L)的吡唑取代基与铜离子(Ⅱ)通过Cu—N的配位键作用形成笼状配合物8(Cu3L2),在配合物8中,两个配体分子7(L)采取顺式面面相向的构象.

关键词： 1,3,5-三乙基苯衍生物超分子化合物自组装金属配合物

控制型指导与研究生能力增长——基于2021年“全国硕士研究生学习和发展”调查数据的分析

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高等教育研究 2021年第9期42卷 52-61页

作者：彭湃胡静雯华中科技大学教育科学研究院湖北武汉430074

控制型指导是导师采取监督、检查和限制等方式来指导研究生的一种行为模式。导师主要实施工作进度控制、工作范围控制和私人空间控制三种行为。基于2021年"全国硕士研究生学习和发展"的调查数据,发现三种控制行为实施比例依次降低。理... 详细信息

控制型指导是导师采取监督、检查和限制等方式来指导研究生的一种行为模式。导师主要实施工作进度控制、工作范围控制和私人空间控制三种行为。基于2021年"全国硕士研究生学习和发展"的调查数据,发现三种控制行为实施比例依次降低。理工农学等实验学科、较低年龄段、就职于较低学术层次高校的导师更有可能对硕士生实施控制型指导。导师实施工作进度和工作范围的控制有利于硕士生能力增长,导师对硕士生私人空间实施控制则起负面作用。控制型指导的积极影响主要经由硕士生的学习投入发挥中介作用,其中科研学习投入的中介作用大于课程学习投入,情感态度投入起调节作用。控制型指导对于情感态度投入较低硕士生的能力增长具有较大的积极影响。

关键词：控制型指导学习投入能力增长硕士研究生