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柑橘溃疡病菌一个单功能域反应调控蛋白的功能研究

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植物病理学报 2024年第3期54卷 535-543页

作者：李瑞芳刘倩倩姚姿婷贤小勇陆光涛朱桂宁广西农业科学院植物保护研究所南宁530017 广西大学生命科学与技术学院南宁530005 农业农村部华南果蔬绿色防控重点实验室/广西作物病虫害生物学重点实验室南宁530017

由柑橘黄单胞柑橘亚种(Xanthomonas citri ***,Xcci)引起的柑橘溃疡病是我国柑橘生产上的一种重要病害。我们在前期研究中发现,Xcci广西菌株N8中有一个与306菌株的XAC3126同源的基因,可能参与调控病原菌的致病性。预测该基因编码一个单... 详细信息

由柑橘黄单胞柑橘亚种(Xanthomonas citri ***,Xcci)引起的柑橘溃疡病是我国柑橘生产上的一种重要病害。我们在前期研究中发现,Xcci广西菌株N8中有一个与306菌株的XAC3126同源的基因,可能参与调控病原菌的致病性。预测该基因编码一个单功能反应调控蛋白。为明确该基因的生物学功能,本研究对该基因进行缺失突变和功能互补,获得了相应的缺失突变体和互补菌株。致病性测定发现,该基因缺失导致Xcci在柑橘上的致病性显著下降,并且其胞外多糖产量、运动性,以及生物膜形成能力均显著降低,而互补菌株的这些表型恢复至野生型水平。进一步通过RT-qPCR分析该基因缺失对Xcci运动性相关基因及胞外多糖相关基因转录的影响,发现相比野生型菌株,缺失突变体在丰富培养基NB中培养时,这些基因的表达均下降,表明该基因的产物是通过调控多种致病因子的表达来影响病原菌在柑橘上的致病性。据此,我们将该基因命名为embR(Extracellular polysaccharide,motility and biofilm formation related regulator)。

关键词：柑橘溃疡病菌单功能域反应调控蛋白致病力调控表达

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火龙果茎溃疡病植株茎组织细菌群落特征分析

南方农业学报 2024年第4期55卷 1023-1034页

作者：梁洲勇姚姿婷曹雪颖韦增亭赵渊朱桂宁邹承武广西大学农学院/植物科学国家级实验教学示范中心广西南宁530004 农业农村部华南果蔬绿色防控重点实验室/广西作物病虫害生物学重点实验室/广西农业科学院植物保护研究所广西南宁530007 广西亚热带作物研究所广西南宁530001

【目的】比较火龙果健康植株与溃疡病植株茎组织的内生细菌群落特征和功能差异,为揭示火龙果溃疡病发生机制和研究防治技术提供理论依据。【方法】采集火龙果健康植株和溃疡病植株茎组织,利用Illumina Miseq测序平台对植株茎组织内生细... 详细信息

【目的】比较火龙果健康植株与溃疡病植株茎组织的内生细菌群落特征和功能差异,为揭示火龙果溃疡病发生机制和研究防治技术提供理论依据。【方法】采集火龙果健康植株和溃疡病植株茎组织,利用Illumina Miseq测序平台对植株茎组织内生细菌的16S rDNA序列进行测定,分析健康植株与罹病植株茎组织中的细菌群落特征差异。【结果】火龙果健康植株茎组织的细菌群落种类和扩增子序列变体(Amplicon sequence variant,ASV)数均低于罹病植株;健康植株与罹病植株茎组织的细菌群落多样性无显著差异(P>0.05)。在细菌优势门中,罹病植株茎组织的放线菌门(Actinobacteriota)、绿弯菌门(Chloroflexi)和异球菌门(Deinococcota)相对丰度较高,而健康植株茎组织的拟杆菌门(Bacteroidota)相对丰度较高。罹病植株茎组织的优势细菌属有27个,其中假单胞菌属(Pseudomonas)、芽孢杆菌属(Bacillus)、鞘氨醇单胞菌属(Sphingomonas)、异球菌属(Deinococcus)、梭菌属(Clostridium_sensu_stricto_1)、短小杆菌属(Curtobacterium)、黄单胞菌属(Xanthomonas)、毛梭菌属(Lachnoclostridium)、微枝形杆菌属(Microvirga)、溶杆菌属(Lysobacter)、Klenkia和类芽孢杆菌属(Paenibacillus)相对丰度较高。健康植株茎组织的优势细菌属有26个,其中绒毛杆菌科未分类属(norank_f_Muribaculaceae)、拟杆菌属(Bacteroides)、乳杆菌属(Lactobacillus)、甲基杆菌属群(Methylobacterium-Methylorubrum)、黄单胞菌科未知属(unclassified_f_Xanthomonadaceae)、副杆菌属(Parabacteroides)、罗尔斯通氏菌属(Ralstonia)、红球菌属(Rhodococcus)、链霉菌属(Streptomyces)、双歧杆菌属(Bifidobacterium)、放线杆菌属(Acinetobacter)和纤维弧菌属(Cellvibrio)的相对丰度较高。线性判别分析(LEfSe)结果显示,健康植株茎组织具有较多指示菌群,而罹病植株茎组织的指示细菌属只有4个不同的属,分别是黄单胞菌属、短小杆菌属、毛梭菌属和新鞘氨醇单胞菌属(Novosphingobium)。细菌功能预测结果显示,溃疡病植株茎组织内生细菌在膜转运、碳水化合物代谢、其他氨基酸代谢和其他次级代谢产物的生物合成等4个二级功能层中的基因拷贝数显著高于健康植株茎(P<0.05)。【结论】火龙果发生茎溃疡病后其茎组织细菌群落多样性无明显改变,但部分优势菌属的比例发生明显改变,其中4个指示细菌属可能与溃疡病发生有关。

关键词：火龙果溃疡病茎组织细菌群落多样性

Sensitivities of Phytophthora infestans to Metalaxyl, Cymoxanil, and Dimethomorph

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Agricultural Sciences in China 2008年第7期7卷 831-840页

作者： zhu gui-ning HUANG Fu-xin FENG Lan-xiang QIN Bi-xia YANG Yu-hong CHEN Yong-hui LU Xiu-hong Institute of Plant Protection Guangxi Academy of Agricultural Sciences Nanning 530007 P.R.China Institute of Vegetable and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

The isolates of Phytophthora infestans on tomato in the Guangxi zhuang Autonomous Region, China, were determined for the sensitivities to metalaxyl, cymoxanil and dimethomorph to give the basic information for integrating disease management. Sensitivities were tested by measuring the radial growth on agar medium amended with fungicide, compared with the floating-leaf-disk method. 239 isolates were collected from eight tomato growing areas during 2000-2006. The testing results indicated that the frequencies of sensitive, intermediate, and resistant isolates to metalaxyl were 42.26, 35.98, and 23.53%, respectively. Variations in sensitivities amongst isolates from different areas or different years were very high for metalaxyl. All isolates from Tianlin and Wuxuan were sensitive to metalaxyl, but the metalaxyl-resistant isolates predominated in Tianyang, with the frequency of 51.35%. The EC50 values of certain isolates from Tianyang were higher than 500 μg·mL^-1 and their resistance levels were over 100 000 folds. Cymoxanil has been used for nearly 10 years in Guangxi, and dimethomorph has been used for 5-6 years. However, there was no decrease in sensitivity of P. infestans populations and the sensitivities of the pathogen were nearly normally distributed. Hence, their mean ECs0 value [cymoxanil （0.1647 ±0.0255） μg·mL^-1, dimethomorph （0.0970 ± 0.0052） μg·mL^-1 could be used as the baseline sensitivities for monitoring the field resistance development. The comparison with the floating-leaf-disk method indicates that both the techniques provided equivalent results. These studies suggested that metalaxyl can be continuously applied in Tianlin, Wuxuan, and Nanning due to the resistant isolates that have not been found, while for those areas with resistant isolate, the use of metalaxyl should be reduced or alternated, and cymoxanil or dimethomorph was recommended for controlling late blight disease of tomato.

关键词： Phytophthora infestans metalaxyl cymoxanil dimethomorph sensitivity

Synthesis of a High-Efficiency Demulsifier and Study on Optimal Demulsification Conditions

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 107-115页

作者： zhu Shuai Zhang YingYu gui Xia College of Chemical Engineering Nanjing Tech University30 Puzhunan RoadNanjing 211816China

Oil and water separation has always been a top priority in the oil *** this study,a series of hyperbranched fluorinated polyamine-amine polymers(HFPA1-5)were synthesized directly using an improved“one-pot method.”The highly active fluorinated p-trifluoromethylaniline was used as the core raw material,while diethylenetriamine and methyl acrylate were used as the chain segment.A hyperbranched fluorine-containing polyamine-amine demulsifier(NHFPA6)was obtained through nano-grafting copolymerization of *** enhance the demulsification and dehydration performance,the copolymerized HFPA6 was modified and ***,the effects of the combination ratio,demulsifier concentration,demulsification time,and demulsification temperature on the demulsification effect were *** results revealed that a combination ratio of DE-401:NHFPA6=1:1,a demulsification temperature of 50℃,a demulsification time of 60 min,and a demulsifier concentration of 150 mg/L yielded a dehydration rate as high as 99.80%.A response surface optimization design of demulsification conditions was *** model verified that the optimal demulsification conditions were 50℃,300 mg/L,and 90 ***,considering the economic benefits of factories,it is more favorable to select demulsification conditions with a shorter time and lower concentration when the dehydration standard is ***,the demulsification conditions were selected as 50℃,150 mg/L,and 60 *** to existing demulsifiers,the demulsifier developed in this study exhibits a lower demulsification temperature and higher demulsification efficiency.

关键词： hyperbranched fluorinated polyamine-amine nano-SiO_(2)

Machine Learning-Based Research on Tensile Strength of SiC-Reinforced Magnesium Matrix Composites via Stir Casting

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 453-466页

作者： Zhihong zhu Wenhang ning Xuanyang Niu Yuhong Zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

SiC is the most common reinforcement in magnesium matrix composites,and the tensile strength of SiC-reinforced magnesium matrix composites is closely related to the distribution of *** a uniform distribution of SiC requires fine control over the parameters of SiC and the processing and preparation ***,due to the numerous adjustable parameters,using traditional experimental methods requires a considerable amount of experimentation to obtain a uniformly distributed composite ***,this study adopts a machine learning approach to explore the tensile strength of SiC-reinforced magnesium matrix composites in the mechanical stirring casting *** analyzing the influence of SiC parameters and processing parameters on composite material performance,we have established an effective predictive ***,six different machine learning regression models have been developed to predict the tensile strength of SiC-reinforced magnesium matrix *** validation and comparison,our models demonstrate good accuracy and reliability in predicting the tensile strength of the composite *** research findings indicate that hot extrusion treatment,SiC content,and stirring time have a significant impact on the tensile strength.

关键词： Machine learning Stirring casting Magnesium matrix composite Tensile strength

Formation Characteristics of CO_(2) Hydrates in the Presence of Porous Media and NaCl

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 168-177页

作者： Han Jianchao zhu Shuai gui Xia College of Chemical Engineering Nanjing Tech UniversityNanjing 211816China

Hydrate-based CO_(2) sequestration is an effective method for reducing the greenhouse effect,and the presence of porous media and NaCl can impact the formation characteristics of *** study uses the constant volume temperature search method to investigate the effects of quartz sand particle size(0.006‒0.03 mm),water saturation(30%–90%),and NaCl concentration(1%‒9%)on the phase equilibrium and kinetics of CO_(2) hydrates within a temperature range of 273‒285 K and pressure range of 1.0‒3.5 *** results indicate that a decrease in quartz sand particle size or an increase in NaCl concentration shifts the hydrate phase equilibrium curve towards lower temperatures and higher pressures,making hydrate generation conditions more *** different particle size systems,there are no significant changes in the rate of CO_(2) hydrate formation or conversion *** highest hydrate conversion rate of 71.1%is observed in a 0.015 mm particle size *** increasing water saturation,both the generation rate and conversion rate of CO_(2) hydrates show a trend of first increasing and then ***,low concentrations of NaCl(1%–3%)are found to enhance the formation and conversion rates of CO_(2) ***,as NaCl concentration increases,the rate of CO_(2) hydrate formation and conversion rate decrease.

关键词： CO_(2)hydrate porous medium NaCl formation characteristics

Structure of the mantle transition zone in the central and western parts of the North China Craton using the receiver function 3D Kirchhoff migration method

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Science China Earth Sciences 2024年第9期67卷 2783-2795页

作者： Min zhu Qingju WU Jieyuan ning Ruiqing ZHANG Institute of Geophysics China Earthquake AdministrationBeijing 100081China Institute of Theoretical and Applied Geophysics Peking UniversityBeijing 100871China

Using data from the regional broadband dense temporary array deployed by the ChinArray project,we applied the three-dimensional(3D)Kirchhoff migration method of the teleseismic P-wave receiver function to investigate discontinuity structures of the mantle transition zone(MTZ)in the central and western parts of the North China Craton(NCC)using a highresolution 3D velocity model of the East Asian *** results show that the 410-km discontinuity beneath the Datong Volcano is depressed by~10 km,indicating the presence of a high-temperature anomaly near the depth of 410 km,which is likely related to small-scale mantle upwelling caused by the dehydration of the stagnant Pacific Plate in the *** upwelling of hot material provides a heat source for surface magmatic *** the Bohai Bay Basin,significant subsidence of the 660-km discontinuity is observed,and the transition zone here is extensively ***’s suggested that the anomalies in this region are related to the stagnation of the Pacific slab in the *** the thickness of the transition zone west of the North-South Gravity Lineament appears normal,we propose that the subducting front of the Pacific slab did not cross the gravity lineament in the *** comparison,the small-scale subsidence of the 660-km discontinuity and the thickening of the MTZ observed north of the Hannuoba Volcano likely indicate that the slab crossed the gravity lineament at its turning point and remained in the ***,a local thickening of the MTZ is observed in the Dabie orogenic belt of the Qinling *** is believed to be a combined effect of lithospheric delamination into the transition zone in the lower Yangtze region and the stagnation of the Pacific Plate.

关键词： North China Craton Mantle transition zone Receiver function migration Datong Volcano

Phosphine-Catalyzed [4+3] Annulation Reaction of Indole Derivatives with MBH Carbonates:A Facile Access to Indole-1,2-fused 1,4-Diazepinones and Azepines

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Chinese Journal of Chemistry 2024年第3期42卷 271-275页

作者： Yannan zhu Haoran Jiang Yi-ning Wang Faculty of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu224051 China

A phosphine-catalyzed [4+3] annulation between dinucleophilic indole derivatives and Morita−Baylis−Hillman (MBH) carbonates was discovered by using the N1 and N4′/C4′ nucleophilicities of the indole precursors,in which indoles act as four atom synthons. This protocol provides an efficient and facile access to indole-1,2-fused 1,4-diazepinones and azepines in good to high yields in one step,which illustrates potential synthetic utilities in drug discovery.

关键词： Phosphine catalysis [4+3]Annulation Indole derivatives Nitrogen heterocycles Organocatalysis

A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 893-906页

作者： Zhipeng Chen Xinyi Wang Weihua gui Jilin zhu Chunhua Yang Zhaohui Jiang The authors are with the School of Automation Central South UniversityChangsha 410083China

Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking *** has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)*** on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is *** with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh *** on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined *** experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting.

关键词： Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging starlight