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云南光唇鱼鳃的组织结构和超微结构观察

四川农业大学学报 2024年第3期42卷 666-671页

作者：龙文玉琚枳豪王云峰牛敏敏裴莹常学秀向乾乾昆明学院农学与生命科学学院/云南高原湖泊生态与环境健康协同创新中心昆明650214 云南大学生态与环境学院昆明650091 云南省水产技术推广站昆明650034

【目的】调查云南光唇鱼(Acrossocheilus yunnanensis)鳃的组织结构和超微结构特点,为丰富云南光唇鱼的生物学基础信息提供资料。【方法】利用透射和扫描等多种电镜技术,分析云南光唇鱼鳃组织和细胞的显微结构与超微结构。【结果】云南... 详细信息

【目的】调查云南光唇鱼(Acrossocheilus yunnanensis)鳃的组织结构和超微结构特点,为丰富云南光唇鱼的生物学基础信息提供资料。【方法】利用透射和扫描等多种电镜技术,分析云南光唇鱼鳃组织和细胞的显微结构与超微结构。【结果】云南光唇鱼的鳃有4对完整的鳃片,每一个鳃片主要由鳃丝、鳃弓和鳃耙3部分组成。云南光唇鱼鳃丝的表面细胞比较丰富和多样,主要包括黏液细胞、扁平上皮细胞和线粒体密集细胞。在这些细胞中扁平上皮细胞是云南光唇鱼鳃表面最丰富的细胞,其表面的形态结构也最为丰富主要呈现环形微嵴、短纹和星点棒状。云南光唇鱼的鳃弓和鳃耙表面主要有两种细胞类型,主要为环形微嵴的扁平上皮细胞和杯状的黏液细胞。【结论】云南光唇鱼鳃的形态和结构特征与其他硬骨鱼类相似,云南光唇鱼鳃的组织结构特征与其在生境中执行气体交换和离子调节息息相关。

关键词：云南光唇鱼鱼鳃显微结构超微结构

The cytosolic isoform of triosephosphate isomerase,ZmTPI4,is required for kernel development and starch synthesis in maize(Zea mays L.)

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The Crop Journal 2024年第2期12卷 401-410页

作者： wenyu Li Han Wang Qiuyue Xu long Zhang Yan Wang Yongbiao Yu Xiangkun Guo Zhiwei Zhang Yongbin Dong Yuling Li State Key Laboratory of Wheat and Maize Crop Science Collaborative Innovation Center of Henan Grain CropsCollege of AgronomyHenan Agricultural UniversityLongzi Lake CampusZhengzhou 450046HenanChina

Triosephosphate isomerase(TPI)is an enzyme that functions in plant energy production,accumulation,and conversion.To understand its function in maize,we characterized a maize TPI mutant,zmtpi4.In comparison to the wild type,zmtpi4 mutants showed altered ear development,reduced kernel weight and starch content,modified starch granule morphology,and altered amylose and amylopectin content.Protein,ATP,and pyruvate contents were reduced,indicating ZmTPI4 was involved in glycolysis.Although subcellular localization confirmed ZmTPI4 as a cytosolic rather than a plastid isoform of TPI,the zmtpi4 mutant showed reduced leaf size and chlorophyll content.Overexpression of ZmTPI4 in Arabidopsis led to enlarged leaves and increased seed weight,suggesting a positive regulatory role of ZmTPI4 in kernel weight and starch content.We conclude that ZmTPI4 functions in maize kernel development,starch synthesis,glycolysis,and photosynthesis.

关键词： Maize Kernel Starch Weight Photosynthesis

Mutations and intron polymorphisms in voltage-gated sodium channel genes of different geographic populations of Culex pipiens pallens/ Culex pipiens quinquefasciatus in China

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贫困所致传染病(英文) 2024年第2期13卷 1-11页

作者： Li wenyu Ma Delong Mu Qunzheng Zhou Xinxin Hua Dongdong Zhao Chunchun Liu Qiyong Wang Jun Meng Fengxia State Key Laboratory of Infectious Disease Prevention and Control Department of Vector Biology and Control National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention WHO Collaborating Centre for Vector Surveillance and Management Beijing People’s Republic of China Ningxia Center for Disease Prevention and Control YinChuan NingXia People’s Republic of China Jinan Shizhong Center for Disease Control and Prevention Jinan Shandong China Vanke School of Public Health Tsinghua University Beijing People’s Republic of China Weifang No. People’s Hospital Weifang Shandong People’s Republic of China Beijing Daxing Center for Disease Control and Prevention Beijing People’s Republic of China Jinan Second Maternal and Child Health Hospital Jinan Shandong China

Background Culex pipiens pallens andCulex pipiens quinquefasciatus are the dominant species ofCulex mosquitoes in China and important disease vectors. long-term use of insecticides can cause mutations in the voltage-gated sodium channel (vgsc) gene of mosquitoes, but little is known about the current status and evolutionary origins ofvgsc gene in different geographic populations. Therefore, this study aimed to determine the current status ofvgsc genes inCx. p. pallens andCx. p. quinquefasciatus in China and to investigate the evolutionary inheritance of neighboring downstream introns of thevgsc gene to determine the impact of insecticides on long-term evolution.Methods Sampling was conducted from July to September 2021 in representative habitats of 22 provincial-level administrative divisions in China. Genomic DNA was extracted from 1308 mosquitoes, the IIS6 fragment of thevgsc gene on the nerve cell membrane was amplified using polymerase chain reaction, and the sequence was used to evaluate allele frequency and knockdown resistance (kdr) frequency. MEGA 11 was used to construct neighborjoining (NJ) tree. PopART was used to build a TCS network.Results There were 6 alleles and 6 genotypes at the L1014 locus, which included the wild-type alleles TTA/L and CTA/L and the mutant alleles TTT/F, TTC/F, TCT/S and TCA/S. The geographic populations with akdr frequency less than 20.00% were mainly concentrated in the regions north of 38° N, and the geographic populations with akdr frequency greater than 80.00% were concentrated in the regions south of 30° N.kdr frequency increased with decreasing latitude. And within the same latitude, the frequency ofkdr in large cities is relatively high. Mutations were correlated with the number of introns. The mutant allele TCA/S has only one intron, the mutant allele TTT/F has three introns, and the wild-type allele TTA/L has 17 introns.Conclusions Cx. p. pallens andCx. p. quinquefasciatus have developed resistance to insecticides in most regions of China. The neighboring downstream i

关键词： Culex pipiens pallens Culex pipiens quinquefasciatus vgsc gene Mutation Frequency Intron Haplotype China

The variation of DOM during long distance water transport by the China South to North Water Diversion Scheme and impact on drinking water treatment

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 85-100页

作者： Hankun Yang Yujuan Li Hongyu Liu Nigel J.D.Graham Xue Wu Jiawei Hou Mengjie Liu wenyu Wang Wenzheng Yu State Key Laboratory of Environmental Aquatic Chemistry Key Laboratory of Drinking Water Science and TechnologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China School of Environment and Municipal Engineering Qingdao Technological UniversityQingdao266033China Colleges of Forestry Northeast Forestry UniversityHarbin150006China Department of Civil and Environmental Engineering Imperial College LondonSouth Kensington CampusLondonSW7 2AZUK School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing100081China State Key Laboratory of Separation Membrane Processes School of Environment Science and EngineeringTiangong UniversityTianjin300387China

In this study,samples were taken from three locations,upstream to downstream,along the central route project of the China South to North Water Diversion(SNWD)scheme in summer and winter.These were used to reveal the variations of dissolved organic matter(DOM)during the water transfer process,and the effects of these variations on drinking water treatment and disinfection by-products formation potential(DBPs-FP).The results showed that polysaccharides accumulate in summer and reduce in winter with flow distance,which has an important effect on the overall properties of DOM,as well as on the performance of coagulation,ultrafiltration,and the formation of DBPs.Humic substances,and their hydrophilic content,also increased in summer and decreased in winter with flow distance.In contrast,the concentration of small organic substances(MW⩽1000 Da)increased in both summer and winter with flow distance,which affected both nanofiltration(NF)membrane fouling and DBPs-FP.The results provide a useful case study of spatial and temporal changes in raw water DOM during long distance water transfer and their impact on the treatment and quality of drinking water from the SNWD.

关键词： long-distance water transfer The China South to North Water Diversion Scheme Coagulation Membrane filtration Disinfection by-products

Elevational distribution of forests and its spatiotemporal dynamics in subtropical China from 2000 to 2019

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Science China Earth Sciences 2024年第8期67卷 2563-2582页

作者： Zhencan ZHENG Liuwen ZHUANG Guofang MIAO Han LIU Zhiqiang CHENG wenyu LI Rong SHANG Peng GONG Jing Ming CHEN Institute of Geography Fujian Normal University Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education) Fujian Normal University School of Geographical Sciences Fujian Normal University National Land Consolidation Center Ministry of Natural Resources Key Laboratory of Land Consolidation and Rehabilitation Ministry of Natural Resources Key Laboratory of Digital Mapping and Land Information Application Ministry of Natural Resources Department of Geography & Planning University of Toronto Department of Geography The University of Hong Kong

The subtropical region of China possesses abundant forest resources and features a mountainous terrain. Under the implementation of policies such as natural forest protection, the Grain for Green Project, and other initiatives since the beginning of the 21st century, coupled with climate change, the forest resources in this region have undergone significant changes compared to historical periods. In addition, forest resources distributing mainly in mountainous areas also implies that these changes may vary significantly with elevation. To explore the spatiotemporal dynamics of forest distribution in subtropical China since 2000,especially the trend of changes with elevation, we analyzed the data from two land cover products focusing on forest cover and forest types. We used a hierarchical approach, in which coarse-classification forest cover data with relatively small uncertainties impose constraints on forest type data with larger uncertainties, to achieve a reasonable balance between obtaining more details and reducing data uncertainty. We first divided the forest cover data into ‘unchanged' and ‘changed' categories. With the constraints by the forest cover results, we further analyzed the ‘unchanged' and ‘changed' forest types. The results indicated that,since the implementation of ecological engineering and management policies, 54% of the area in the subtropical region had maintained unchanged forest cover attributes over the past 20 years, which implied the good state of ecological environment. The results also showed that dynamic conversions existed in the long term between forests and lands for essential production needs like croplands. The elevational variations of forest cover suggested that the dominant changes came from the conversion between forests and croplands in low-elevation regions below 700 m, the conversion between forests and shrublands in mid-elevation regions of 700–1500 m, and the conversion between forests and grasslands in high-elevation regions above 2000 m. In the regions with unchange

关键词： Subtropical China Land cover Forest cover Forest type Elevational distribution

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新型液固循环移动床流动特性的实验研究

化学反应工程与工艺 2007年第1期23卷 35-41页

作者：聂向锋龙文宇卢春喜时铭显中国石油大学(北京)重质油国家重点实验室北京102249

在新型液-固循环移动床反应-再生冷模装置中,以水-玻璃珠为液-固体系,对φ300 mm×3000 mm的液-固循环移动床再生器内的操作域和流动特性进行了研究。实验结果表明,下料管出口和料位高度的相对位置对床层流动状态有较大影响,当料位高度... 详细信息

在新型液-固循环移动床反应-再生冷模装置中,以水-玻璃珠为液-固体系,对φ300 mm×3000 mm的液-固循环移动床再生器内的操作域和流动特性进行了研究。实验结果表明,下料管出口和料位高度的相对位置对床层流动状态有较大影响,当料位高度高于下料管出口高度时,床层流动可以分为局部流化床区和移动床区两个区域。随着表观再生液速的增大,移动床区先后经历了移动床流动和散式流化床流动,移动床流动的操作液速为0～6.5 mm/s,散式流化床流动的操作液速为6.5～20.5 mm/s。随着表观再生液速的增大,移动床层各轴向高度颗粒平均速率均增大,表观再生液速超过一定值后,颗粒平均速率基本不变。在各轴向高度床层上,随着表观再生液速的增大,局部流化床区周向影响区中心夹角不断增大。

关键词：液-固循环移动床操作区域床层压降颗粒速率

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梯形移动床径向反应器内颗粒的贴壁现象分析

化工学报 2014年第4期65卷 1179-1185页

作者：龙文宇徐军范怡平卢春喜中国石油大学(北京)化工学院北京102249 辽宁石油化工大学石化学院辽宁抚顺113001

贴壁现象是制约移动床反应器操作弹性的瓶颈之一。在高度为1.3 m、顶部宽度为0.185 m、底部宽度为0.299m、厚度为0.04 m的梯形径向移动床冷模实验装置上考察了颗粒层的贴壁现象。记录不同的操作条件下,贴壁与空腔现象产生的位置及形状大... 详细信息

贴壁现象是制约移动床反应器操作弹性的瓶颈之一。在高度为1.3 m、顶部宽度为0.185 m、底部宽度为0.299m、厚度为0.04 m的梯形径向移动床冷模实验装置上考察了颗粒层的贴壁现象。记录不同的操作条件下,贴壁与空腔现象产生的位置及形状大小,并测量了气体通过床层的压降。随着表观气速的增加,贴壁层变厚,空腔变大,呈现为渐进型贴壁;而颗粒循环强度对贴壁与空腔现象无影响。通过力平衡分析建立了梯形床贴壁现象的数学模型,引入矫正因子对模型进行修正,模型计算值与实验值基本相符。

关键词：移动床贴壁颗粒物料粉体技术模型

湘莲不同器官中常见重金属含量检测及富集特征分析

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食品与机械 2024年第3期40卷 60-67页

作者：戴慧赵文玉王建辉贺湘怡龙潇长沙理工大学化学化工学院湖南长沙410114 长沙理工大学水利与环境工程学院湖南长沙410114 国家环境保护重金属污染监测重点实验室湖南长沙410114 长沙理工大学食品与生物工程学院湖南长沙410114 湖南省水生资源食品加工工程技术研究中心湖南长沙410114

目的:了解湘莲种植区底泥及湘莲不同器官中常见重金属含量,进而探究湘莲各部位对重金属的富集转移特征。方法:以湖南省典型湘莲种植区为研究对象,通过ICP-OES检测底泥及湘莲不同器官中Cd、Cr、Pb、Ni、Cu、Zn、Mn含量;采用生物富集系数(... 详细信息

目的:了解湘莲种植区底泥及湘莲不同器官中常见重金属含量,进而探究湘莲各部位对重金属的富集转移特征。方法:以湖南省典型湘莲种植区为研究对象,通过ICP-OES检测底泥及湘莲不同器官中Cd、Cr、Pb、Ni、Cu、Zn、Mn含量;采用生物富集系数(BCF)和生物转移系数(TF)评价湘莲对重金属的富集转移特征。结果:底泥中Cd、Cr、Pb、Ni、Cu、Zn、Mn含量均值分别为0.73,176.28,40.48,27.61,28.07,95.57,311.68 mg/kg,与NY/T 391—2021限量值相比,Cd、Cr、Pb含量的超标率分别为100%,75%,10%。湘莲中7种重金属的最高富集器官:莲芯中为Cd、Cu、Zn,莲根中为Cr、Pb,去芯莲肉中为Ni,莲叶中为Mn,其含量均值分别为0.20,13.64,78.58,14.66,2.23,1.11,924.03 mg/kg。仅莲茎和莲叶中的BCF Mn均值>1,各器官中的TF Cu值均>1。结论:研究区以Cd污染相对严重;湘莲不同器官重金属含量不同,莲茎及莲叶对Mn有较强富集作用,Cu在湘莲内转移能力较强。

关键词：湘莲重金属污染生物富集生物转移

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新辅助化疗联合同步放化疗治疗中晚期宫颈癌的临床价值

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智慧健康 2024年第5期10卷 63-65,70页

作者：黄龙穆文玉王侠徐州医科大学附属医院江苏徐州221000

目的分析新辅助化疗联合同步放化疗治疗中晚期宫颈癌效果。方法选取2021年1月—2023年1月本院收治的80例中晚期宫颈癌患者为研究对象,依据随机数字表法分两组,对照组行同步放化疗,观察组加用新辅助化疗,对比疗效。结果经不同方案治疗... 详细信息

目的分析新辅助化疗联合同步放化疗治疗中晚期宫颈癌效果。方法选取2021年1月—2023年1月本院收治的80例中晚期宫颈癌患者为研究对象,依据随机数字表法分两组,对照组行同步放化疗,观察组加用新辅助化疗,对比疗效。结果经不同方案治疗,观察组患者总缓解率为97.50%,与对照组的85.00%对比较高,差异有统计学意义(P0.05);治疗后,观察组患者CD3+、CD4+水平大于对照组患者,CD8+水平小于对照组,差异有统计学意义(P0.05)。观察组患者生活质量总分(78.24±2.16)分,与对照组患者的(68.25±2.35)分对比较高,且各指标分值均比观察组较高,差异有统计学意义(P<0.05)。结论中晚期宫颈癌患者治疗期间,在同步放化疗基础上实施新辅助化疗可进一步强化疗效,在调节T细胞亚群方面具有显著优势,且并未增加不良反应风险,安全可行。

关键词：新辅助化疗同步放化疗中晚期宫颈癌