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FgGyp8 as a putative FgRab1 GAP is required for growth and pathogenesis by regulating FgSnc1-mediated secretory vesicles fusion in Fusarium graminearum

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Journal of Integrative Agriculture 2023年第11期22卷 3444-3457页

作者： zhang xing-zhi CHEN Shuang Yakubu Saddeeq ABUBAKAR MAO Xu-zhao MIAO Peng-fei WANG Zong-hua ZHOU Jie ZHENG Hua-wei Fujian Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity/Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops Minjiang UniversityFuzhou 350108P.R.China Fujian University Key Laboratory for Plant-Microbe Interaction College of Life SciencesFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Department of Biochemistry Faculty of Life SciencesAhmadu Bello UniversityZaria 810211Nigeria

Fusarium graminearum is an important plant pathogenic fungus that causes disease and yield reduction in many cereal crops, such as wheat and barley. Gyp8 stimulates GTP hydrolysis on Ypt1 in yeast. However, the functions of Gyp8 in plant pathogenic fungi are still unknown. In this study, we investigated the roles of Fg Gyp8 in F. graminearum by genetic and pathological analyses. Through gene knockout and phenotypic analyses, we found that Fg Gyp8 is required for vegetative growth in F. graminearum. The conidiation, conidial size and number of septa per conidium of ΔFggyp8 mutant are significantly reduced when compared to the wild type PH-1. Furthermore, Fg Gyp8 is crucial for pathogenicity on wheat coleoptiles and wheat heads. Fg Gyp8 contains a conserved TBC domain. Domain deletion analysis showed that the TBC domain, C-and N-terminal regions of Fg Gyp8 are all important for its biological functions in F. graminearum. Moreover, we showed that Fg Gyp8 catalyzes the hydrolysis of the GTP on Fg Rab1 to GDP in vitro, indicating that Fg Gyp8 is a GTPase-activating protein(GAP) for Fg Rab1. In addition, we demonstrated that Fg Gyp8 is required for Fg Snc1-mediated fusion of secretory vesicles with the plasma membrane in F. graminearum. Finally, we showed that Fg Gyp8 has functional redundancy with another Fg Rab1 GAP, Fg Gyp1, in F. graminearum. Taken together, we conclude that Fg Gyp8 is required for vegetative growth, conidiogenesis, pathogenicity and acts as a GAP for Fg Rab1 in F. graminearum.

关键词： Fusarium graminearum FgGyp8 GTPase-activating protein FgRab1 conidiogenesis pathogenicity

Effects of seasonal variations on soil microbial community composition of two typical zonal vegetation types in the Wuyi Mountains

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Journal of Mountain Science 2016年第6期13卷 1056-1065页

作者： WU Ze-yan LIN Wen-xiong LI Jian-ju LIU Jin-fu LI Bai-lian WU Lin-kun FANG Chang-xun zhang zhi-xing Life Sciences College of Fujian Agriculture and Forestry University Fuzhou 350002 China Ecological Complexity and Modeling Laboratory University of California Riverside Riverside CA92507 USA Forestry College of Fujian Agriculture and Forestry University Fuzhou 350002 China Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring School of Life Sciences Fujian Agriculture and Forestry University Fuzhou 350002 China Key Laboratory of Crop Ecology and Molecular Physiology (Fujian Agriculture and Forestry University) Fujian Province University Fuzhou 350002 China

Seasonal shifts play an important role in soil microbial community composition. This study examined the hypothesis that soil microbial community structure would vary with seasonal shifts in the Wuyi Mountains in Southeast China, and that two representative tree species （Castanopisi carlesii and Cunninghamia lanceolata） may have different soil microbial community composition. Phospholipids fatty acid analysis （PLFA） of seasonal shifts and was used to assess the effect vegetation types on soil microbial community structure. A total of 22 different PLFAs were identified from all the soil samples. The bacterial PLFAs accounted for 62.37% of the total PLFAs, followed by fungi （28.94%）, and the minimum was actinomycetes （6.41%）. Overall, the level of PLFAs in C. carlesii soil was greater than those in C. lanceolata soil, and significant differences were observed in some seasons. The amounts of total, bacteria, actinomycic and fungal PLFAs significantly changed with the seasons and followed a sequence order （summer 〉 autumn 〉 spring 〉 winter）. The bacteria/fungi PLFAs and G （＋）/G （-） PLFAs of two vegetation types also changed with the seasons and the ratios in summer and autumn were higher than those in spring and winter. The correlation analysis of microbial PLFAs and soil physicochemical properties showed that the total, bacteria, fungal, actinomycic, G （＋） and G （-） PLFAs were significantly positive correlation with TOC, TN, TP, TK and moisture content. We concluded that the seasonal shifts and vegetation types affect soil microbial community composition by changing the soil physicochemical properties.

关键词： Seasonal shifts Soil microbes Community composition Castanopisi carlesii Cunninghamia lanceolata

温度与载荷对GH4169/5CrMnMo界面接触换热的影响

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中南大学学报（自然科学版） 2009年第6期40卷 1568-1572页

作者：邢磊张立文张兴致大连理工大学材料科学与工程学院辽宁大连116085

基于传热学基本原理建立合理简化的热接触模型。应用稳态法,通过自制的实验设备对GH4169高温合金与5CrMnMo模具钢的界面接触换热系数进行测量。根据实验数据归纳出接触换热系数的经验计算关系式,比较计算结果和实验结果。研究结果表明:... 详细信息

基于传热学基本原理建立合理简化的热接触模型。应用稳态法,通过自制的实验设备对GH4169高温合金与5CrMnMo模具钢的界面接触换热系数进行测量。根据实验数据归纳出接触换热系数的经验计算关系式,比较计算结果和实验结果。研究结果表明:接触界面温度变化范围为240～560℃,接触载荷能够达到15.68MPa;接触换热系数随界面温度和接触载荷的增加呈现增大趋势,但在320℃和470℃附近出现换热系数的极小值,温度与载荷的作用是通过改变材料热物性及力学性能间接实现的;经验计算关系式满足幂律关系,引入修正系数α和δ后,能够合理地预测接触换热系数,计算结果与实验结果较吻合。

关键词：界面温度接触载荷接触换热系数经验关系式

Effects of residual water on microtensile bond strength of one-bottle dentin adhesive systems with different solvent bases

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Chinese Medical Journal 2005年第19期118卷 1623-1628页

作者： zhang zhi-xing HUANG Cui ZHENG Tie-li WANG Sa CHENG Xiang-rong Department of Prosthodontics School of Stomatology WuhanUniversity Wuhan 430079 China Key Laboratory for Oral Biomedical Engineering of Ministry ofEducation School of Stomatology Wuhan University Wuhan430079 China

Background The wet-bonding technique is recommended for the one-bottle dentin adhesive systems, but the moisture concept varies widely among the instructions of manufacturers as well as among investigators. The aim of this study was to evaluate the effects of different dentin surface moisture on the microtensile bond strength （s） of an ethanol/water-based adhesive system and an acetone-based system to dentin. Methods Forty intact human premolars extracted for orthodontic reasons were used. Superficial occlusal flat dentin surfaces of these premolars were exposed, finished with wet 600-grit silicon carbide paper. Under four wet and dry conditions （overwet, blot dry, one-second dry and desiccated）, resin composite was bonded to dentin by using Single Bond （SB） or Prime ＆ Bond NT （PB） according to the manufacturers＇ instructions. The teeth were longitudinally sectioned in the “x” and “y” directions to obtain bonded beams with a cross-sectional area of 0. 81 mm^2 with a slow-speed diamond saw. The bonded specimens were tested in tension at a crosshead speed of 1 mm/min until failure of the bonds. Failure modes were observed with a scanning electron microscope. The mean bond strengths were analyzed by one-way ANOVA and Turkey＇s test. Results The bond strength of the overwet/SB, blot dry/SB, one-second dry/SB and desiccated/SB groups was 10.87 MPa, 22.47 MPa, 24.91 MPa and 12. 99 MPa, respectively. The bond strength of the overwet/PB, blot dry/PB, one-second dry/PB and desiccated/PB groups was 10.02 MPa, 20. 67 MPa, 21.82 MPa and 10. 09 MPa, respectively. For both SB and PB, the blot dry group and one-second dry group revealed significantly higher bond strengths than the overwet and desiccated groups （P 〈0.05）. Conclusions In order to achieve the highest bond strength to dentin, keeping appropriately moist condition is critical for the one-bottle dentin adhesive systems with solvent. the dentin surface in an ethanol/water or acetone

关键词： dentin-bonding agents microtensile bond strength moisture

Optimal management of nitrogen fertilizer in the main rice crop and its carrying-over effect on ratoon rice under mechanized cultivation in Southeast China

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Journal of Integrative Agriculture 2022年第2期21卷 351-364页

作者： HUANG Jin-wen WU Jia-yi CHEN Hong-fei zhang zhi-xing FANG Chang-xun SHAO Cai-hong LIN Wei-wei WENG Pei-ying Muhammad Umar KHAN LIN Wen-xiong Key Laboratory for Genetics Breeding and Multiple Utilization of Crops Ministry of Education/College of AgricultureFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Key Laboratory of Crop Ecology and Molecular Physiology(Fujian Agriculture and Forestry University) Fujian Province UniversityFuzhou 350002P.R.China Institute of Soil Fertilizer and Resources Environment Jiangxi Academy of Agricultural SciencesNanchang 330200P.R.China

This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast *** on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test *** results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main *** same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading *** same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon *** transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 *** canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon ***,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that

关键词： main crop ratoon rice nitrogen management crop stand low stubble height grain yield

A CLOSED FORM SOLUTION TO STRESS INTENSITY FACTORS OF SHEAR MODE FOR CIRCULAR TUBE WITH HOLE EDGE CORNER CRACKS

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Chinese Journal of Aeronautics 1993年第1期 1-12页

作者： Wang Qi-zhi,zhang xing,He Qing-zhi (Beijing University of Aeronautics and Astronautics,Beijing,China,100083) Ren Bing-yi (Chendu Aircraft Company,Chendu,China,610092)

A closed form solution to stress intensity factors of shear mode for a circular tubewith non—through-thickness hole edge cracks is derived by means of the energy releaserate method. This method is used to formulate a classical Bernoulli’s differential equationabout the amplitude of crack sliding displacements with respect to the parameter of virtualcrack extension. The equation has a closed form solution and the integration can be carriedout by variable separation. The stress intensity factors Kand Kare determined bythe amplitude of crack sliding displacements. The mode of crack sliding displacements isgiven by the two dimensional assumptions of radial and circumferential slices of the circulartube. This closed form solution of energy release rate method is very tune-saving and acomplete series of useful results can be obtained. The results degenerate into the cases offlat plates and fit very well with those given by alternating method.

关键词： mode FORM A CLOSED FORM SOLUTION TO STRESS INTENSITY FACTORS OF SHEAR MODE FOR CIRCULAR TUBE WITH HOLE EDGE CORNER CRACKS EDGE

TP2铜与3Cr2W8V模具钢的瞬态接触换热系数

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中国有色金属学报 2010年第4期20卷 662-666页

作者：邢磊张立文张兴致岳重祥大连理工大学材料科学与工程学院大连116085

基于反传热算法,制造一套瞬态接触换热系数测量装置,研究高温TP2铜与低温3Cr2W8V模具钢的瞬态接触换热过程。结果表明:接触载荷在1.56～7.80MPa范围内变化时,高温TP2铜的初始温度为400、500和600℃,低温3Cr2W8V模具铜的初始温度为100、... 详细信息

基于反传热算法,制造一套瞬态接触换热系数测量装置,研究高温TP2铜与低温3Cr2W8V模具钢的瞬态接触换热过程。结果表明:接触载荷在1.56～7.80MPa范围内变化时,高温TP2铜的初始温度为400、500和600℃,低温3Cr2W8V模具铜的初始温度为100、200和300℃。瞬态接触换热系数在很短时间内(5s)快速增大到某一恒定值,并随着时间延长,产生缓慢的后续增加过程。接触换热系数随着接触载荷的增加而增大,呈幂指数关系,且试样初始温度越高,接触换热系数增大的趋势越快。

关键词： TP2铜 3Cr2W8V模具钢瞬态法反传热算法接触换热系数

孔子学院对“一带一路”沿线国家贸易便利化影响的实证分析

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经济经纬 2018年第6期35卷 66-72页

作者：姜慧张志醒鲁东大学商学院山东烟台264000 河南财经政法大学国际经济与贸易学院河南郑州450046

分别使用两种贸易便利化指标的测算办法,利用差分GMM和系统GMM两种估计方法考察了孔子学院对"一带一路"沿线国家贸易便利化的影响。研究发现:孔子学院可以减少两国地理或文化距离的负面影响,提高"一带一路"沿线国家的贸易便利化;孔子学... 详细信息

分别使用两种贸易便利化指标的测算办法,利用差分GMM和系统GMM两种估计方法考察了孔子学院对"一带一路"沿线国家贸易便利化的影响。研究发现:孔子学院可以减少两国地理或文化距离的负面影响,提高"一带一路"沿线国家的贸易便利化;孔子学院可以通过影响中国对"一带一路"沿线国家的直接投资和对外贸易等因素促进其贸易便利化的提高;孔子学院对"一带一路"沿线国家贸易便利化的推动作用有着明显的区域差异性。所以,我国应注重加强与"一带一路"沿线国家的双边文化交流和中华文化的传播,通过孔子学院助力"一带一路"沿线国家贸易便利化的提高。

关键词： “一带一路” 贸易便利化孔子学院

Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan zhang Lianghao JI Shasha YANG xing GUO Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control