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Dynamics of bacterial communities during a seasonal hypoxia at the Bohai Sea:Coupling and response between abundant and rare populations

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Journal of Environmental Sciences 2022年第1期34卷 324-339页

作者： Chao Wu jinjun kan Dhiraj Dhondiram Narale Kun Liu Jun Sun Tianjin Key Laboratory of Marine Resources and Chemistry Tianjin University of Science and TechnologyTianjin 300457China Research Centre for Indian Ocean Ecosystem Tianjin University of Science and TechnologyTianjin 300457China Department of Microbiology Stroud Water Research CenterAvondalePA 19311USA Laboratory of Marine Biology and Ecology Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China College of Marine Science and Technology China University of Geosciences(Wuhan)Wuhan 430074China

Marine bacterial community plays a vital role in the formation of the hypoxia zone in coastal ***,their dynamics in the seasonal hypoxia zone of the Bohai Sea(BHS)are barely ***,the 16S r RNA gene-based high-throughput sequencing was used to explore the dynamics of their diversity,structure,and function as well as driving factors during the gradual deoxygenation process in the *** results evinced that the bacterial community was dominated by Proteobacteria,followed by Bacteroidetes,Firmicutes,Actinobacteria,and Cyanobacteria,*** abundant subcommunity dominated in the number of sequences(49%)while the rare subcommunity dominated in the number of species(99.61%).Although abundant subcommunity accounted for most sequences,rare subcommunity possessed higher diversity,richness and their population dramatically changed(higher turnover)during the hypoxia ***,co-occurrence network analysis proved the vital role of rare subcommunity in the process of community ***,beta diversity partition revealed that both subcommunities possessed a higher turnover component than nestedness and/or richness component,implying species replacement could explain a considerable percentage of community *** variation might be governed by both environmental selection and stochastic processes,and further,it influenced the nitrogen cycle(PICRUSt-based prediction)of the hypoxia ***,this study provides insight into the spatial-temporal heterogeneity of bacterial and their vital role in biogeochemical cycles in the hypoxia zone of the *** findings will extend our horizons about the stabilization mechanism,feedback regulation,and interactive model inside the bacterial community under oxygen-depleted ecosystems.

关键词： Bacterial community Hypoxia Stratification The Bohai Sea Nitrogen cycles High-throughput sequencing

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Regeneration and utilization of nutrients during collapse of a Mesodinium rubrum red tide and its influence on phytoplankton species composition

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Science China Earth Sciences 2018年第10期61卷 1384-1396页

作者： Yafeng ZHANG Xiuxian SONG Paul J.HARRISON Sheng LIU Zhiming YU jinjun kan Peiyuan QIAN Hao LIU Kedong YIN School of Marine Sciences Sun Yat-Sen University Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Department of Earth Ocean & Atmospheric Sciences University of British Columbia Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Microbiology Division Stroud Water Research Center 970 Spencer Road Division of Life Science Hong Kong University of Science and Technology

High-biomass red tides occur frequently in some semi-enclosed bays of Hong Kong where ambient nutrients are not high enough to support such a high phytoplankton biomass. These high-biomass red tides release massive inorganic nutrients into local waters during their collapse. We hypothesized that the massive inorganic nutrients released from the collapse of red tides would fuel growth of other phytoplankton species. This could influence phytoplankton species composition. We tested the hypothesis using a red tide event caused by Mesodinium rubrum(M. rubrum) in a semi-enclosed bay, Port Shelter. The red tide patch had a cell density as high as 5.0×10~5 cells L^(-1), and high chlorophyll a(63.71 μg L^(-1)). Ambient inorganic nutrients(nitrate:NO_3^-, ammonium: NH_4^+, phosphate: PO_4^(3-), silicate: SiO_4^(3-)) were low both in the red tide patch and the non-red-tide patch(clear waters outside the red tide patch). Nutrient addition experiments were conducted by adding all the inorganic nutrients to water samples from the two patches followed by incubation for 9 days. The results showed that the addition of inorganic nutrients did not sustain high M. rubrum cell density, which collapsed after day 1, and did not drive M. rubrum in the non-red-tide patch sample to the same high-cell density in the red tide patch sample. This confirmed that nutrients were not the driving factor for the formation of this red tide event, or for its collapse. The death of M. rubrum after day 1 released high concentrations of NO_3^-,PO_4^(3-), SiO_4^(3-), NH_4^+, and urea. Bacterial abundance and heterotrophic activity increased, reaching the highest on day 3 or 4, and decreased as cell density of M. rubrum declined. The released nutrients stimulated growth of diatoms, such as Chaetoceros affinis var. circinalis, Thalassiothrix frauenfeldii, and Nitzschia sp., particularly with additions of SiO_4^(3-) treatments, and other species. These results demonstrated that initiation of M. rubrum red tid

关键词： Red tides Species composition Nutrients Regeneration Mesodinium rubrum

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Co-monitoring bacterial and dinoflagellates communities by denaturing gradient gel electrophoresis (DGGE) and SSU rRNA sequencing during a dinoflagellates bloom

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Acta Oceanologica Sinica 2004年第3期23卷 483-492页

作者： kanjinjun CHENFeng CenterofMarineBiotechnology UniversityofMarylandBiotechnologyInstituteBaltimoreMD21202

Dinoflagellates are unicellular eukaryotic protists that dominate in all coastal waters, and are also present in oceanic waters. Despite the central importance of dinoflagellates in global primary production, the relationship between dinoflagellates and bacteria are still poorly understood. In order to understand the ecological interaction between bacterial and dinoflagellates communities, denaturing gradient gel electrophoresis (DGGE) and SSU rRNA sequencing were applied to monitoring the population dynamics of bacteria and dinoflagellates from the onset to disappearance of a dinoflagellates bloom occurred in Baltimore Inner Harbor, from April 15 to 24,2002. Although Prorocentrum minimum was the major bloom forming species under the light microscopy, DGGE method with dinoflagellate specific primers demonstrated that Prorocentrum micans, Gymnodinium galatheanum and Gyrodinium uncatenum were also present during the bloom. Population shifts among the minor dinoflagellate groups were observed. DGGE of PCR-amplified 16S rRNA gene fragments indicated that cyanobacteria, α, β, γ-proteobacteria, Flavobacterium Bacteroides-Cytophaga (FBC), and Planctomcetes were the major components of bacterial assemblages during the bloom. DGGE analysis showed that Cytophagales and α-proteobacteria played important roles at different stages of dinoflagellates bloom. DGGE can be used as a rapid tool to simultaneously monitor population dynamics of both bacterial and dinoflagellates communities in aquatic environments, which is demonstrated here.

关键词： bacteria dinoflagellates DGOE SSU rDNA sequencing

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河口细菌群落多样性及其控制因素:以切萨皮克湾为例

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生物多样性 2011年第6期19卷 770-778页

作者：阚金军孙军 Stroud Water Research Center 970 Spencer RoadAvondalePA 19311USA 天津科技大学海洋科学与工程学院

咸淡水的混合和重要营养盐与有机物的再循环,使得河口成为地球上生产力较高而动态变化明显的水生生态系统。一个典型的河口区断面中,细菌群落包含了一些从淡水到海洋的过渡类型:例如a-变形菌(Alphaproteobacteria)、-变形菌(Betaproteob... 详细信息

咸淡水的混合和重要营养盐与有机物的再循环,使得河口成为地球上生产力较高而动态变化明显的水生生态系统。一个典型的河口区断面中,细菌群落包含了一些从淡水到海洋的过渡类型:例如a-变形菌(Alphaproteobacteria)、-变形菌(Betaproteobacteria)、?-变形菌(Gammaproteobacteria)、蓝细菌(Cyanobacteria)[聚球藻(Synechococcus)]、拟杆菌(Bacteroidetes)、放线细菌(Actinobacteria)和疣微菌(Verrucomicrobia)等。此外,河口也包含其独特的细菌群落:SAR11组、玫瑰杆菌属(Roseobacter)、SAR86和放线细菌(Actinobacteria)的一些进化亚枝(subclades),表明海湾或者大型温带河口区细菌类群具有区域生态适应性。以研究较多的美国切萨皮克湾(Chesapeake Bay)为例,其细菌群落呈现出显著的季节性变化和周期性的年际变化特征;这些变化除了受水的滞留时间和细菌生长速度影响外,还可能受其他许多环境因子的影响。其中叶绿素a和水温变化的影响最大,其他环境因子如溶解氧、铵态氮、亚硝酸盐和硝酸盐以及病毒的丰度也有影响。近年来,基于群落水平的基因组学(genomics)和后基因组学(postgenomics)(转录组学和蛋白质组学)技术应用于研究自然条件下微生物群落错综复杂的基因多样性和表达,提供了揭示水环境中微生物群落组成和新功能基因的途径。

关键词：遗传多样性浮游细菌基因组学后基因组学切萨皮克湾

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Apatite and Chitin Amendments Promote Microbial Activity and Augment Metal Removal in Marine Sediments

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Open Journal of Metal 2013年第2期3卷 51-61页

作者： jinjun kan Anna Obraztsova Yanbing Wang Jim Leather Kirk G. Scheckel Kenneth H. Nealson Y. Meriah Arias-Thode Department of Earth Sciences University of Southern California Los Angeles USA National Risk Management Research Laboratory Environmental Protection Agency Cincinnati USA SPAWAR Systems Center-Pacific San Diego USA Stroud Water Research Center Avondale USA

In situ amendments are a promising approach to enhance removal of metal contaminants from diverse environments including soil, groundwater and sediments. Apatite and chitin were selected and tested for copper, chromium, and zinc metal removal in marine sediment samples. Microbiological, molecular biological and chemical analyses were applied to investigate the role of these amendments in metal immobilization processes. Both apatite and chitin promoted microbial growth. These amendments induced corresponding bacterial groups including sulfide producers, iron reducers, and phosphate solubilizers;all that facilitated heavy metal immobilization and removal from marine sediments. Molecular biological approaches showed chitin greatly induced microbial population shifts in sediments and overlying water: chitin only, or chitin with apatite induced growth of bacterial groups such as Acidobacteria, Betaproteobacteria, Epsilonproteobacteria, Firmicutes, Planctomycetes, Rhodospirillaceae, Spirochaetes, and Verrucomicrobia;whereas these bacteria were not present in the control. Community structures were also altered under treatments with increase of relative abundance of Deltaproteobacteria and decrease of Actinobacteria, Alphaproteobacteria, and Nitrospirae. Many ?of these groups of bacteria have been shown to be involved in metal reduction and immobilization. Chemical analysis ?of pore and overlying water also demonstrated metal immobilization primarily under chitin treatments. X-Ray absorption spectroscopy (XAS) spectra showed more sorbed Zn occurred over time in both apatite and chitin treatments (from 9% - 27%). The amendments improved zinc immobilization in marine sediments that led to significant changes in ??the mineralogy: easily mobile Zn hydroxide phase was converted to an immobile Zn phosphate (hopeite). In-situ amendment of apatite and chitin offers a great bioremediation potential for marine sediments contaminated with heavy metals.

关键词： Apatite Chitin Amendments Marine Sediment DGGE Microbial Community Copper Zinc Chromium

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四型机场与四强空管有机统一浅谈

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民航学报 2021年第4期5卷 29-31页

作者：阚劲军周中雨中国民航信息网络股份有限公司中航信民航旅客服务智能化应用技术重点实验室

2017年及2018年,中国民用航空局领导先后提出了"四型机场"与"四强空管",为我国民航面向新时代发展指明了方向和要求。本文聚焦四型机场与四强空管的辩证统一,进行论述与分析,重在强调两者的内在统一和紧密关系。通过文章,力求将四型机... 详细信息

2017年及2018年,中国民用航空局领导先后提出了"四型机场"与"四强空管",为我国民航面向新时代发展指明了方向和要求。本文聚焦四型机场与四强空管的辩证统一,进行论述与分析,重在强调两者的内在统一和紧密关系。通过文章,力求将四型机场与四强空管有机结合,从内容与内涵解析到分步实施和落地举措,在我国已经基本实现从航空运输大国向单一的航空运输强国的"转段进阶"后,为面向2035年我国民航高质量发展提供理论依据和指导。

关键词：四型机场四强空管平安绿色效率智慧协同

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典型相关分析在四型机场建设评价中应用

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综合运输 2020年第5期42卷 31-34页

作者：阚劲军眭永波中国民航信息网络股份有限公司北京101318 中航信民航旅客服务智能化应用技术重点实验室北京101318

四型机场是中国民航局于2018年提出的面向新时代民航强国战略的具体举措,包括平安机场、绿色机场、智慧机场、人文机场四个关键特征。本文将典型相关分析技术引入民航四型机场建设评价体系中,基于典型相关分析的理论和方法助力四型机场... 详细信息

四型机场是中国民航局于2018年提出的面向新时代民航强国战略的具体举措,包括平安机场、绿色机场、智慧机场、人文机场四个关键特征。本文将典型相关分析技术引入民航四型机场建设评价体系中,基于典型相关分析的理论和方法助力四型机场评价指标设计更加科学合理。通过本文论述的技术和方法,有助于将四型机场建设评价体系定性分析转化为定量分析,增强了四型机场建设评价体系的科学性,并为四型机场评价指标体系迭代修正过程提供了科学依据和理论支撑,从而以更扎实的数据分析依据达到了较好的分析效果。

关键词：航空运输四型机场典型相关分析评价指标一级指标二级指标

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装配成功率可控、面向成本优化的尺寸链容差设计

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机械设计与研究 2024年第4期40卷 25-30页

作者：杨宇龙韩彪洪巾钧杨洪刘衎潘絮微魏冕凌云科技集团有限责任公司信息数字化室武汉430040 凌云科技集团有限责任公司机电一车间湖北当阳444100 凌云科技集团有限责任公司零备件事业部湖北当阳444100

采用蒙特卡罗法求解、遗传算法优化来进行尺寸链容差设计,设计目标是在装配成功率真实可控的前提条件下尽量优化机械加工的成本。通过深入分析,装配成功率经成本优化后会极限接近合格线,这样会导致两个问题:(1)经重复多次采样,装配成功... 详细信息

采用蒙特卡罗法求解、遗传算法优化来进行尺寸链容差设计,设计目标是在装配成功率真实可控的前提条件下尽量优化机械加工的成本。通过深入分析,装配成功率经成本优化后会极限接近合格线,这样会导致两个问题:(1)经重复多次采样,装配成功率的值分布在及格线上下,其中大量不合格;(2)遗传算法每代最优个体无法长久保存,导致优化效率低下。文中采用二次采样蒙特卡罗法将装配成功率的采样波动纳入考虑,有效解决了上述两个问题,得到的结果更符合设计目标的要求。

关键词：容差设计遗传算法蒙特卡罗法尺寸链装配成本优化

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Temperature-sensitive and solvent-resistance hydrogel sensor for ambulatory signal acquisition in“moist/hot environment”

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Nano Research 2023年第7期16卷 10348-10357页

作者： Xinyu Qu Hanjun Sun Xiaolong kan Bing Lei jinjun Shao Qian Wang Wenjun Wang Zhenhua Ni Xiaochen Dong Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) School of Physical and Mathematical SciencesNanjing Tech University(NanjingTech)Nanjing 211816China School of Physical Science and Information Technology Liaocheng UniversityLiaocheng 252059China School of Physics and Key Laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 211189China School of Chemistry&Materials Science Jiangsu Normal UniversityXuzhou 221116China

To realize continuously and stably work in a“moist/hot environment”,flexible electronics with excellent humid resistance,antiswelling,and detection sensitivity are ***,a solvent-resistant and temperature-ultrasensitive hydrogel sensor was prepared by combining MXene and quaternized chitosan(QCS)with the binary polymer *** strong electrostatic interaction between the QCS chain and the poly(acrylic acid)(PAA)network endows the hydrogel stability against solvent erosion,high temperature,and high *** strong dynamic interaction between MXene and polymer matrix significantly improves the mechanical properties and sensing(strain and temperature)sensitivity of the *** hydrogel strain sensor exhibits a high gauge factor(5.53),temperature/humidity tolerance(equilibrium swelling ratio of 2.5%at 80℃),and excellent cycle stability,which could achieve a remote and accurate perception of complex human motion and environment fluctuation under aquatic ***,the hydrogel sensor exhibits impressive thermal response sensitivity(-3.183%/℃),ultrashort response time(<2.53 s),and a low detection limit(<0.5℃)in a wide temperature range,which is applied as an indicator of the body surface and ambient *** short,this study broadens the application scenarios of hydrogels in persistent extreme thermal and wet environments.

关键词： flexible electronics hydrogel sensor solvent-resistance underwater application

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三维立方周期阵列石膏基材料吸波性能仿真与实验研究

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材料导报 2021年第12期35卷 12020-12026页

作者：朱连诚冀志江解帅张远王静张琎珺李衎李飞中国建筑材料科学研究总院有限公司北京100024 绿色建筑材料国家重点实验室北京100024 中央军委机关事务管理总局第三保障处北京100120 中国人民解放军32378部队北京100072

基于三维立方周期阵列结构,以乙炔炭黑为吸波剂,设计了一种具有宽频特性的石膏基吸波材料。HFSS(High frequency structure simulator)仿真结果显示,三维周期阵列单元的边长、高度、基层厚度及炭黑质量分数会对材料的吸波性能及有效频... 详细信息

基于三维立方周期阵列结构,以乙炔炭黑为吸波剂,设计了一种具有宽频特性的石膏基吸波材料。HFSS(High frequency structure simulator)仿真结果显示,三维周期阵列单元的边长、高度、基层厚度及炭黑质量分数会对材料的吸波性能及有效频段产生显著影响。试验结果显示,对于周期阵列单元边长为10 mm、高度为5 mm、基层厚度为10 mm、炭黑含量为2%的试样,其在4.2~18 GHz范围内的反射率低于-10 dB,有效频带宽度可达13.8 GHz以上。试验结果与仿真结果具有较高的吻合度。该材料的电磁波损耗主要来自于乙炔炭黑的电阻损耗和三维周期阵列的结构效应。

关键词：三维周期阵列石膏基材料吸波宽频

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