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Chinese Geographical Science 2019年第1期29卷 1-12页

作者： ding liuyong CHEN Liqiang ding Chengzhi TAO Juan Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan University Institute of International Rivers and Eco-security Yunnan University

Dam removal has been increasingly reported globally and is becoming an important approach for river management, restoration and environmental conservation in damming rivers. However, current limited knowledge of global trends in dam removal and related research may be potentially biased in terms of the geographic distribution and organisms studied. Such bias could mislead dam removal planning and management in different areas and ecological conservation for different taxa. In this study, we quantitatively and qualitatively analyzed datasets of dam removal and publications of dam removal research using bibliometric methods. A total of 1449 dam removal documents were published from 1953 to 2016. Trends, current hotspots and future directions of dam removal research were identified. The results from this study reveal that dam removal largely occurred in the North America and Europe, and most of the removed dams were small and old dams. With respect to the topic analysis, more dam removal studies should focus on the responses of a wide range of organisms, not only fish, as well as the interspecies relationships, food webs and ecosystem structures and functions. Based on our findings, we also provide some suggestions for future dam removal planning and analysis.

关键词： dam demolition literature research topics weir

Fish Assemblage Responses to a Low-head Dam Removal in the Lancang River

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Chinese Geographical Science 2019年第1期29卷 26-36页

作者： ding Chengzhi JIANG Xiaoming WANG Lieen FAN Hui CHEN Liqiang HU Jinming WANG Hailong CHEN Yifeng SHI Xiaotao CHEN Hao PAN Bohui ding liuyong ZHANG Chao HE Daming Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan University State Key Laboratory of Eco-hydraulic in Northwest Arid Region of China Xi'an University of Technology Huaneng Lancang River Hydropower Co. Ltd Laboratory of Biological Invasion and Adaptive Evolution Institute of Hydrobiology Chinese Academy of Sciences Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of Education China Three Gorges University

Dam removal is becoming an effective approach for aquatic biodiversity restoration in damming river in order to balance the aquatic ecosystem conservation with large-scale cascade damming. However, the effects of dam removal on fish communities in Asian mountainous rivers, which are dominated by Cypriniformes fishes, are still not well known. To determine whether dam removal on a mountainous river benefit restoration of fish diversity, we investigated the response of fish assemblage to dam removal using a before-after-control-impact design in two tributaries of the Lancang River(dam removal river: the Jidu River, and control river: the Fengdian River). Fish surveys were conducted one year prior to dam removal(2012) and three years(2013–2015) following dam removal. We observed rapidly and notably spatio-temporal changes in fish biodiversity metrics and assemblage structure, occurring in the Jidu River within the first year after dam removal. Overall, fish species richness, density and Shannon-Wiener diversity all increased immediately in above-and below-dam sites, and maintained a stable level in subsequent years, compared to unchanged situation in the control river. All sites in the Jidu River experienced shifts in fish composition after dam removal, with the greatest temporal changes occurred in sites below-and above-the former dam, resulting in a temporal homogenization tendency in the dam removed river. These findings suggest that dam removal can benefit the recovery of habitat conditions and fish community in Asian mountainous rivers, but the results should be further evaluated when apply to other dammed rivers since the dam age, fluvial geomorphology and situation of source populations could all affect the responses of fish assemblages.

关键词： fish diversity dam demolition habitat recovery Cypriniformes international rivers

Cloning and Characterization of the fecC Gene Necessary for Optimal Growth under Iron-Deficiency Conditions in the Cyanobacterium Anabaena sp. PCC7120

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Wuhan University Journal of Natural Sciences 2004年第4期9卷 498-502页

作者： xuwen-liang liuyong-ding ZHANGCheng-cai LIJuan CollegeofLifeSciences CentralChinaNormalUniversityWuhan430079HubeiChina InstituteofHydrobiology ChineseAcademyofSciencesWuhan430072HubeiChina CollegeofLifeSciencesandTechnology HuazhongAgriculturalUniversityWuhan430070HubeiChina CollegeofLifeSciences CentralChinaNormalUniversityWuhan430079HubeiChina

ThefecC gene encoding a putative iron (III) dicitrate transporter was cloned from nitrogen-fixing cyanobacteriumAnabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO 3 ? , NH 4 + or without combined nitrogen. But in iron-deficient medium, the mutant grows slowly. Photosynthetic properties were compared between the mutant and the wildtype strain, the content of photosynthetic pigments in the mutant is lower than that of the wild-type. The results of RT-PCR experiments show that thefecC gene is expressed under iron-deficient conditions, but is not expressed under iron-replete conditions. These results revealed thatfecC gene product is required for optimal growth under iron-deficient conditions inAnabaena sp. PCC 7120. Key words Anabaena sp. PCC 7120 - fecC - iron deficiency - photosynthetic properties - expression CLC number Q 933 Foundation item: Supported by the National Natural Sciences Foundation of China (30070154), the Frontier Science Projects Program of the Institute of Hydrobiology, the Chinese Academy of Sciences (220316), State Key Project on Cyanobacterial Bloom Control in Lake Dianchi (K99-05-35-01)Biography: XU Wen-liang (1974-), male, Ph. D, research direction: molecular genetics of cyanobacteria.

关键词： Anabaena sp. PCC 7120 fecC iron deficiency photosynthetic properties expression

Effect of Iron Deficiency on Heterocyst Differentiation and Physiology of the Filamentous Cyanobacterium Anabaena sp. PCC 7120

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Wuhan University Journal of Natural Sciences 2003年第3A期8卷 880-884页

作者： XuWen-liang liuyong-ding ZhangCheng-cai InstituteofHydrobiology ChineseAcademyofSciencesWuhan430072HubeiChina LaboratoiredeChimieBacterienne(UPR9043) CNRS31CheminJosephAiguier13402Marseillecedex20France

The effect of iron deficiency on heterocyst differentiation and some physiological properties of the filamentous cyanobacterium Anabaena sp. PCC 7120 was investigated. Under moderate iron limitation conditions, achieved by addition of iron chelator 2,2′\|Dipyridyl (<80 μmol/L) led to delayed heterocyst differentiation, no heterocyst differentiation was observed under severe iron limitation conditions, when the concentration of 2,2′\|Dipyridyl in the medium was more than 100 μmol/L . It seemed that there are certain iron\|regulated genes or operons whose function is to control heterocyst development. In addition, iron deficiency impaired the growth. Low\|iron cells had a decrease in the quantities of pigment content (chlorophyll and phycocyanin content),the whole cell in vivo absorbance spectra confirmed the decrease, the protein electrophoretic profiles revealed that iron\|deficient cells had less protein bands, with the increase of 2,2′\|Dipyridyl ,the protein bands was more and more less. And differently, iron deficiency also caused an increase of ROS (Reactive Oxygen Species)and SOD activity, it suggests that iron deficiency led to oxidative stress, which generally occured under high\|iron conditions.

关键词： Anabaena sp. PCC 7120 iron deficiency heterocyst development protein SDS \|PAGE oxidative stress

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怒江流域鱼类多样性及空间分布格局

生物多样性 2022年第7期30卷 117-129页

作者：杨科丁城志陈小勇丁刘勇黄敏睿陈晋南陶捐云南大学国际河流与生态安全研究院昆明650500 云南省国际河流与跨境生态安全重点实验室昆明650500 中国科学院昆明动物研究所遗传资源与进化国家重点实验室昆明650223

怒江是我国西南地区重要的国际河流,也是全球生物多样性热点区域之一。受地理位置和地形条件限制,目前尚缺乏怒江流域鱼类物种多样性及其分布格局的系统研究。本研究利用近5年的全流域实地采样数据,结合文献资料,系统整理了怒江流域鱼... 详细信息

怒江是我国西南地区重要的国际河流,也是全球生物多样性热点区域之一。受地理位置和地形条件限制,目前尚缺乏怒江流域鱼类物种多样性及其分布格局的系统研究。本研究利用近5年的全流域实地采样数据,结合文献资料,系统整理了怒江流域鱼类物种组成信息;利用聚类和排序方法分析了怒江流域鱼类空间分布格局。结果表明,怒江流域共有土著鱼类85种,隶属于5目12科47属;外来鱼类18种,隶属于3目8科16属,另外实地调查发现新记录外来种2种。怒江流域鱼类多样性从上游至下游呈明显的递增趋势。根据土著鱼类组成的聚类和排序分析结果,可以将怒江25个亚流域分为3个部分:(1)西藏自治区内的上游河段,分布有鱼类15种,组成以裂腹鱼类、高原鳅类为主,具有明显青藏高原冷水性鱼类区系特征。(2)贡山至泸水的中游河段,分布有鱼类36种,组成兼有上游冷水性鱼类和下游喜温的鲃亚科、野鲮亚科鱼类。(3)泸水以下的下游河段,分布有鱼类74种。下游河段干流广泛分布有喜温的鲃亚科、野鲮亚科和亚科鱼类,支流则分布有数量众多的南鳅属(Schistura)、纹胸鮡属(Glyptothorax)鱼类,鱼类组成以适应流水、激流环境的热带亚热带鱼类为主。2017–2021年的多次调查仅发现土著鱼类43种(占历史记录的50.6%),土著鱼类资源衰退明显。过度捕捞、支流小水电开发、外来鱼类入侵等是主要威胁因素。随着人类活动的急剧增多,怒江流域鱼类将面临更大的威胁,亟需从流域层面开展系统的鱼类资源管理和保护规划。

关键词：鱼类物种丰富度多样性格局相似性分析怒江国际河流

FinFET芯片TEM样品制备及避免窗帘效应方法

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微纳电子技术 2023年第8期60卷 1301-1307页

作者：胡康康王刘勇黄亚敏郎莉莉董业民王丁上海理工大学材料与化学学院上海200082 中国科学院上海微系统与信息技术研究所上海200050

制备高质量纳米尺度芯片透射电子显微镜(TEM)样品对于探索半导体器件结构设计、材料分布与芯片性能之间的关系具有重要的意义。使用聚焦离子束(FIB)/扫描电子显微镜(SEM)双束系统制备14 nm鳍式场效应晶体管(FinFET)截面TEM样品,制备过... 详细信息

制备高质量纳米尺度芯片透射电子显微镜(TEM)样品对于探索半导体器件结构设计、材料分布与芯片性能之间的关系具有重要的意义。使用聚焦离子束(FIB)/扫描电子显微镜(SEM)双束系统制备14 nm鳍式场效应晶体管(FinFET)截面TEM样品,制备过程中从技术角度提出了两种自下而上制样方案来抑制窗帘效应。为扩大样品的可表征视场范围,在避免样品弯曲的前提下,提出了一种薄片提取方法。结果表明,离子束流越大,窗帘效应越严重,自下而上方法能有效规避窗帘效应;离子束电压30 kV时采用清洗截面(CCS)模式、5 kV/2 kV时采用矩形模式,样品台倾斜补偿角度为1.5°~3.5°,进行交叉减薄,且最终铣削长度控制在1μm时减薄效果最好;新的薄片提取方法改变了样品的铣削方向,在避免窗帘效应破坏感兴趣结构和样品弯曲的前提下,将样品的可表征视场范围扩大了5倍。研究结果对优化TEM样品制备方法以及芯片失效分析提供了参考。

关键词：聚焦离子束(FIB) 透射电子显微镜(TEM)样品 14 nm鳍式场效应晶体管(FinFET) 窗帘效应失效分析

经尿道膀胱肿瘤电切术联合吡柔比星膀胱灌注化疗在浅表性膀胱癌患者中的应用效果

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癌症进展 2023年第7期21卷 781-784页

作者：胡伟强张刘勇丁宁刘坤龙刘涛西安高新医院泌尿外科西安710065 西安秦皇医院泌尿外科西安7106990

目的探讨经尿道膀胱肿瘤电切术联合吡柔比星膀胱灌注化疗在浅表性膀胱癌患者中的应用效果。方法根据手术方式的不同将90例浅表性膀胱癌分为对照组(n=45)和观察组(n=45),对照组患者采取经尿道膀胱肿瘤电切术治疗,观察组患者采取经尿道膀... 详细信息

目的探讨经尿道膀胱肿瘤电切术联合吡柔比星膀胱灌注化疗在浅表性膀胱癌患者中的应用效果。方法根据手术方式的不同将90例浅表性膀胱癌分为对照组(n=45)和观察组(n=45),对照组患者采取经尿道膀胱肿瘤电切术治疗,观察组患者采取经尿道膀胱肿瘤电切术联合吡柔比星膀胱灌注化疗。比较两组患者的肿瘤标志物[血管内皮生长因子(VEGF)、成纤维细胞生长因子(FGF)、基质金属蛋白酶9(MMP9)、基质金属蛋白酶2(MMP2)]水平、生活质量[健康调查简表(SF-36)]、并发症发生情况及肿瘤复发情况。结果治疗后1周,两组患者血清VEGF、FGF、MMP9、MMP2水平均低于本组治疗前,且观察组患者血清VEGF、FGF、MMP9、MMP2水平均低于对照组,差异均有统计学意义(P﹤0.05)。治疗后1个月,两组患者SF-36量表各维度评分均高于本组治疗前,且观察组患者SF-36量表各维度评分均高于对照组,差异均有统计学意义(P﹤0.05)。对照组患者的并发症总发生率为8.89%,与观察组患者的6.67%比较,差异无统计学意义(P﹥0.05)。随访6个月,对照组患者的复发率为4.44%,与观察组患者的2.22%比较,差异无统计学意义(P﹥0.05);随访1年,观察组患者的1年复发率为4.44%,低于对照组患者的17.78%,差异有统计学意义(P﹤0.05)。结论经尿道膀胱肿瘤电切术联合吡柔比星膀胱灌注化疗治疗浅表性膀胱癌,能够降低血清因子水平,提高患者生活质量,降低术后复发率,且无明显不良反应。

关键词：浅表性膀胱癌经尿道膀胱肿瘤电切术吡柔比星灌注化疗

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怒江裂腹鱼鳃的显微和超微结构

中国水产科学 2018年第6期25卷 1183-1193页

作者：向乾乾丁刘勇张超孙洁王迪丁城志陈礼强云南大学国际河流与生态安全研究院云南省国际河流与跨境生态安全重点实验室

通过光镜、扫描电镜及透射电镜技术,研究了怒江裂腹鱼(Schizothorax nukiangensis)鳃的组织结构和超微结构。结果表明,怒江裂腹鱼鳃基本结构与其他硬骨鱼相似,均由鳃耙、鳃弓、鳃丝以及鳃小片构成,且各部分具有不同的组织结构和细胞类... 详细信息

通过光镜、扫描电镜及透射电镜技术,研究了怒江裂腹鱼(Schizothorax nukiangensis)鳃的组织结构和超微结构。结果表明,怒江裂腹鱼鳃基本结构与其他硬骨鱼相似,均由鳃耙、鳃弓、鳃丝以及鳃小片构成,且各部分具有不同的组织结构和细胞类型。扁平上皮细胞覆盖于整个鳃表面,其表面的纹路主要有3种类型,在鳃上不同的部位具有不同的结构和功能。线粒体密集细胞主要分布于鳃小片基部,仅有一种细胞类型,顶端膜内凹呈浅滩型,细胞内具有大量圆形的线粒体。怒江裂腹鱼鳃内扁平上皮细胞和线粒体密集细胞的形态结构与其在急流中游泳和摄食活动等生活习性相适应。本研究结果丰富了怒江裂腹鱼的基础生物学资料,并为阐明鱼类鳃的结构特征与其生活习性之间的关系提供参考。

关键词：怒江裂腹鱼鳃扁平上皮细胞线粒体密集细胞组织结构超微结构

钬激光碎石术联合经尿道等离子电切术治疗前列腺增生症合并膀胱大结石的效果

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临床医学研究与实践 2022年第3期7卷 66-69页

作者：程伟张刘勇何建光丁宁张志辉汪珂西安高新医院泌尿外科陕西西安710075

目的探讨钬激光碎石术联合经尿道等离子电切术治疗前列腺增生症合并膀胱大结石的效果。方法选择本院2015年5月至2020年4月收治的46例前列腺增生症合并膀胱大结石患者为研究对象,根据随机数字表法将其分为对照组和观察组,各23例。对照组... 详细信息

目的探讨钬激光碎石术联合经尿道等离子电切术治疗前列腺增生症合并膀胱大结石的效果。方法选择本院2015年5月至2020年4月收治的46例前列腺增生症合并膀胱大结石患者为研究对象,根据随机数字表法将其分为对照组和观察组,各23例。对照组行开放取石术联合经尿道等离子电切术,观察组行钬激光碎石术联合经尿道等离子电切术。比较两组的治疗效果。结果观察组的术中出血量少于对照组,取石时间、手术耗时、术后膀胱冲洗时间、拔管时间及住院时间均短于对照组(P<0.05)。术后3个月,两组的最大尿流率、平均尿流率显著增大,残余尿量显著减少,且观察组优于对照组(P<0.05)。术后3个月,两组的IIEF-5评分及GQOLI-74各项评分均升高,IPSS评分均降低,且观察组优于对照组(P<0.05)。观察组的结石排净率明显高于对照组,并发症总发生率低于对照组(P<0.05)。结论采用钬激光碎石术联合经尿道等离子电切术治疗前列腺增生症合并膀胱大结石,能够优化围手术期指标,加速患者术后康复,改善其膀胱功能和生活质量。

关键词：前列腺增生症膀胱大结石钬激光碎石术经尿道等离子电切术开放取石术

高职茶叶生产与加工技术专业人才培养质量调研分析和专业改革建议

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农产品加工 2023年第24期 116-120页

作者：杨留勇吴勇杨森丁丽何志华杨静毕节职业技术学院贵州毕节551700

为提升茶叶生产与加工技术专业的建设水平,通过查阅文献、问卷调查、专门访谈等方式,对毕节市茶叶专业人才队伍现状及需求进行调研分析,并对茶叶生产与加工技术专业教学改革提出建议。结果表明,茶叶行业、企业人员整体技术水平偏低,未来... 详细信息

为提升茶叶生产与加工技术专业的建设水平,通过查阅文献、问卷调查、专门访谈等方式,对毕节市茶叶专业人才队伍现状及需求进行调研分析,并对茶叶生产与加工技术专业教学改革提出建议。结果表明,茶叶行业、企业人员整体技术水平偏低,未来3年对毕业生需求较大。

关键词：茶叶生产与加工技术人才培养调研分析教学改革