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The impact of biotic and abiotic factors on the distribution of surface sediment dinoflagellate cyst assemblages on the Nanji Island in the East China Sea

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Acta Oceanologica Sinica 2019年第1期38卷 160-171页

作者： Han Gao Shengpao You Xiangdong Lei Yunpu Xiao Haifeng Gu mengmeng tong Ocean College Zhejiang University Nanji Marine Environment Monitoring Station Ministry of Natural Resources Pingyang County Marine and Fisheries Bureau Third Institute of Oceanography Ministry of Natural Resources

The dinoflagellate cyst assemblages on the Nanji Island in the East China Sea, are documented at the first time to construct a quantitative overview of the cyst bank from 2014 to 2015. Thirty-four morphotypes from six groups are identified and quantified at eight sampling sites around the island, including a high proportion of potentially toxigenic species(14%). Autotrophic dinocysts constitute 74% of the total cyst counts, which is relatively low(two to thirty-three per millilitre sediment) compared with previous studies in adjacent areas. Scrippsiella trochoidea and Protoperidinium avellana are the most abundant autotrophic and heterotrophic species, respectively. A multivariate analysis is performed to assess associations between dinocysts and abiotic or biotic *** among seasons is evident in the detrended correspondence analysis(DCA) ordination plot, while a spatial pattern is not clearly revealed despite heterogeneity of the hydrodynamic conditions between sampling sites. Soluble reactive phosphate, the ratio of nitrogen to phosphorus concentrations and Karenia mikimotoi bloom are the three factors significantly(P<0.05) related to surface sediment cyst assemblage defined by the canonical correspondence analysis(CCA), highlighting the importance of nutrient regime to a dinocyst distribution in this area. Although attempts to address the origin of HAB events in recent years using seed banks have failed, knowledge can be valuable for further investigation of dinocyst dynamics and potential toxin threats on the Nanji Island.

关键词： dinoflagellate cyst Nanji Island nutrients harmful algal blooms

Research progress in artificial upwelling and its potential environmental effects

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Science China Earth Sciences 2016年第2期59卷 236-248页

作者： PAN YiWen FAN Wei ZHANG DaHai CHEN JiaWang HUANG HaoCai LIU ShuXia JIANG ZongPei DI YaNan tong mengmeng CHEN Ying Ocean College Zhejiang University

Artificial upwelling, as a geoengineering tool, has received worldwide attention because it may actualize ocean fertilization in a sustainable way, which could potentially alleviate the pressures on the fish stocks and human-driven climate change in the ocean. We reviewed the current knowledge on the development of an artificial upwelling system and its potential environmental effects. Special attention was given to the research progress on the air-lift concept artificial upwelling by Zhejiang University. The research on artificial upwelling over the past few decades has generated a range of devices that have been successfully applied in the field for months. Based on field experiments and the associated modeling results, part of them reported positive effects on increasing primary production and enhancing CO2 sequestration. However, as a significant disturbance to the environment, especially for large-scale applications, the uncertainties related to the potential effects on ecosystem remain unsolved. Zhejiang University has overcome the technical challenges in designing and fabricating a robust and high efficiency artificial upwelling device which has been examined in two field experiments in Qiandao Lake and one sea trial in the East China Sea. It was investigated that cold and hypoxic deep ocean water(DOW) could be uplifted to the euphotic layer, which could potentially change the nutrient distribution and adjust the N/P ratio. Both simulation and field experiments results confirmed that utilizing self-powered energy to inject compressed air to uplift DOW was a valid and efficient method. Therefore, further field-based research on artificial upwelling, especially for long-term field research is required to test the scientific hypothesis.

关键词： Artificial upwelling Air-lifting Self-powered Environmental impacts Research progress

Morphological,phylogenetic and metabolite profile of Prorocentrum clipeus,a newly recorded epiphytic dinoflagellate in the northern Yellow Sea

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Acta Oceanologica Sinica 2024年第8期43卷 128-141页

作者： Ruifang Wang mengmeng tong Shiwen Zhou Junjie Zheng Wenguang Zhang Xinfeng Dai Douding Lu Jiarong Hu Tianze Leng Qinglin Mu Zhongyong Yan Jiangning Zeng Pengbin Wang Ocean College Zhejiang UniversityZhoushan 316021China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China The State Key Laboratory of Marine Pollution Department of Biomedical SciencesCity University of Hong KongHong Kong SAR 999077China Zhejiang Marine Ecology and Environment Monitoring Center Zhoushan 316000China

More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of benthic Prorocentrum species have been reported in tropical and subtropical waters of *** contrast,only a few benthic Prorocentrum species have been reported in temperate *** this study,morphological descriptions obtained using light microscopy,scanning electron microscopy and molecular characterization of one Prorocentrum clipeus strain isolated from the Yellow Sea are *** clipeus cells were nearly circular in shape,with a collar,ridge,and one *** periflagellar area was wide U-shaped,with two curved projections on platelet *** periflagellar platelets of different sizes were *** morphology closely fits that of the species isolated from other *** analysis based on the molecular sequences of the small subunit(SSU)rDNA,internal transcribed spacer(ITS),and large subunit(LSU)rDNA was performed.A comprehensive metabolomic analysis incorporating target,suspect and non-target screenings was first applied to investigate the intracellular and extracellular metabolite profiles of the current isolate of *** to the results of the target and suspect screenings,179 metabolites or toxins produced by DSP-related algal species,including OA,dinophysistoxin-1(DTX1),dinophysistoxin-2(DTX2)and pectenotoxin-2(PTX2),were not ***-target screening involving feature-based molecular networking(FBMN)provided a global view of major metabolites produced by the *** DF128 strain and revealed 23 clusters belonging to at least 13 compound classes,with organometallic compounds,lipids and lipid-like molecules,phenylpropanoids and polyketides,and benzenoids as major *** date,this is the first record of the characterization of *** in samples from Chinese *** results suppo

关键词： Prorocentrum taxonomy phylogeny metabolite profiling Yellow Sea

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均衡性转移支付、税制结构与共同富裕

南京审计大学学报 2023年第5期20卷 1-10页

作者：田时中童梦梦安徽大学经济学院安徽合肥230601

新发展阶段,要加快实现共同富裕,就需要重视均衡性转移支付和税制结构的调节作用。基于极值熵值法测度的共同富裕综合指数构建面板Tobit模型、空间滞后模型和门槛模型,从均衡性转移支付和税制结构的不同视角,探究上述因素对共同富裕的... 详细信息

新发展阶段,要加快实现共同富裕,就需要重视均衡性转移支付和税制结构的调节作用。基于极值熵值法测度的共同富裕综合指数构建面板Tobit模型、空间滞后模型和门槛模型,从均衡性转移支付和税制结构的不同视角,探究上述因素对共同富裕的多重影响,结果发现:从基准回归和空间滞后模型看,共同富裕存在显著的空间溢出效应,均衡性转移支付对共同富裕的直接和空间促进效应尚未体现,以直接税和间接税为主体的税制结构的直接和空间效应显著为正,且均衡性转移支付能够调节税制结构的直接和空间溢出效应。进一步分析发现,均衡性转移支付与共同富裕之间存在由“门槛效应”引起的非线性关系,合理的均衡性转移支付显著促进共同富裕,且随着均衡性转移支付的提升,其促进效应不断减弱。动态空间滞后模型显示,共同富裕滞后一期的直接和空间溢出效应均显著为正。以上研究结论对中国政府优化财税体制、推进共同富裕具有重要启示。

关键词：均衡性转移支付税制结构共同富裕空间滞后模型门槛效应收入分配中国式现代化

共性指标下中国财政预算绩效评价实证研究——基于熵值法和矩估计

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财经论丛 2023年第1期 25-34页

作者：田时中李晓悦童梦梦安徽大学经济学院安徽合肥230601

本文基于预算投入、过程和效果三维度共性指标体系和中国31省区市最新面板数据,运用熵值法测度财政预算绩效指数,通过矩估计实证检验财政自主度、政府竞争对财政预算绩效的多重影响效应。结果表明:样本考察期内,中国财政预算绩效综合指... 详细信息

本文基于预算投入、过程和效果三维度共性指标体系和中国31省区市最新面板数据,运用熵值法测度财政预算绩效指数,通过矩估计实证检验财政自主度、政府竞争对财政预算绩效的多重影响效应。结果表明:样本考察期内,中国财政预算绩效综合指数总体呈“波浪式”上升趋势,区域异质性特征明显,东、中、西部三大地区演变趋势逐渐趋同,省际间截面差异较为显著;子系统综合指数大小次序为预算安排>经济效益>生态效益>社会效益>预算执行,且呈不同的变动趋势;财政自主度、政府竞争对财政预算绩效具有负向影响,二者间协同作用并未显著提升财政预算绩效水平;关键控制变量中,人均GDP、人口密度、财政供养人口对财政预算绩效水平的提升具有促进作用,上一年度财政预算绩效、城镇化水平、产业结构、政府官员任期对财政预算绩效具有抑制作用,部分控制变量的影响存在区域异质性。研究结论可为实现预算和绩效管理一体化、深入推进全面预算绩效管理提供经验参考和决策建议。

关键词：政府预算绩效评价熵值法

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化感物质对浒苔孢子附着的抑制效应研究

环境科学与技术 2021年第S1期44卷 26-34页

作者：李乃成张靖尧胡传明佟蒙蒙浙江大学海洋学院浙江舟山316000 江苏省海洋水产研究所江苏南通226007

浒苔为世界广布种,自2007年以来,浒苔引起的绿潮在中国海域连续暴发,给山东沿岸受灾区域造成巨大的经济、生态损失。浒苔具有典型的同型世代交替生活史,二倍体世代的孢子无性生殖是其主要的生殖方式。而孢子释放进入环境后,当遇到合适... 详细信息

浒苔为世界广布种,自2007年以来,浒苔引起的绿潮在中国海域连续暴发,给山东沿岸受灾区域造成巨大的经济、生态损失。浒苔具有典型的同型世代交替生活史,二倍体世代的孢子无性生殖是其主要的生殖方式。而孢子释放进入环境后,当遇到合适的附着基质,便产生粘性糖蛋白附着于基质上,萌发形成的成体大量暴发,进而引起生态危害。基于此,该研究针对浒苔孢子萌发和附着过程,以浒苔孢子细胞诱导形成及附着干预为切入点,首先探索了影响浒苔孢子释放的环境因子,分析了不同类型附着基质对浒苔孢子附着的影响,最后以紫菜栽培区域使用最为广泛的网绳为附着基质,分析、探讨不同结构类型化感物质对浒苔孢子附着的干预能力。结果表明,环境压力如较低的温度和盐度(25℃、25‰)、10~12 h的干出时间和较小的碎片(如1 mm)有利于诱导浒苔孢子形成和释放。孢子对锦纶、维尼纶、尼龙等附着基质并未呈现出明显的附着差异性,这可能与附着基质材料的表面粗糙程度有关。丁香酚、月桂烯、壬酸、柠檬醛、正辛醇、苯甲酸具备抗孢子附着的能力,其中以丁香酚活性最佳(EC_(50)为4.43 mg/L),在2 mg/L浓度下即可对孢子附着产生抑制作用,其次依次为月桂烯、正辛醇、壬酸、柠檬醛和苯甲酸,EC50分别为6.45、7.52、9.25、10.80和12.37 mg/L。对羟基苯甲酸及亚油酸不具备抑制浒苔孢子附着的能力。因此,可将丁香酚作为抑附着剂,月桂烯和正辛醇作为备选抑附着剂,用于抑制浒苔绿潮初期的孢子附着,进而达到在孢子阶段防控浒苔暴发的目的,为绿潮治理提供理论依据。

关键词：浒苔孢子化感作用附着基丁香酚月桂烯

不同应变速率下5B70铝合金的拉伸断口分析

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金属热处理 2020年第3期45卷 231-234页

作者：周巍姜锋赖松柏方杰童蒙蒙中南大学轻合金研究院湖南长沙410083 轻质高强结构材料重点实验室湖南长沙410083 中南大学材料科学与工程学院湖南长沙410083 中国空间技术研究院载人航天总部北京100094

研究了不同应变速率下5B70铝合金的拉伸断口。结果表明:随着应变速率的增加,合金的断后伸长率下降。断口分析表明,应变速率越低,断口中的韧窝数量多且深度深,表现出明显的高韧性断裂。随着应变速率的增加,出现准解理面,合金偏向于脆性... 详细信息

研究了不同应变速率下5B70铝合金的拉伸断口。结果表明:随着应变速率的增加,合金的断后伸长率下降。断口分析表明,应变速率越低,断口中的韧窝数量多且深度深,表现出明显的高韧性断裂。随着应变速率的增加,出现准解理面,合金偏向于脆性断裂。随着应变速率的增加,合金断口侧面晶粒伸长减小,析出相的数量减少。

关键词： 5B70铝合金应变速率显微组织准解理断裂断口分析

“双碳”目标约束下绿色税收的碳排放效应实证检验

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大连海事大学学报（社会科学版） 2023年第1期22卷 59-68页

作者：田时中童梦梦安徽大学经济学院合肥230601

建立扩展STIRPAT模型和固定效应模型,以2010—2020年中国30个省级数据为样本,实证分析绿色税收的碳排放效应。结果显示,在样本考察期内,中国碳排放量增长率有所放缓,但依然存在总量过大的问题。三大地区碳排放量依次为:东部>西部>中部... 详细信息

建立扩展STIRPAT模型和固定效应模型,以2010—2020年中国30个省级数据为样本,实证分析绿色税收的碳排放效应。结果显示,在样本考察期内,中国碳排放量增长率有所放缓,但依然存在总量过大的问题。三大地区碳排放量依次为:东部>西部>中部。整体上狭义和广义绿色税收都显著抑制了碳排放。分区域看,东部地区狭义绿色税收对碳排放的抑制作用最显著,西部地区广义绿色税收对碳排放的抑制作用最显著;分阶段看,2018年开征环境保护税之后,狭义绿色税收对碳排放的抑制作用被削弱,而广义绿色税收的影响程度有所提升。为实现“双碳”目标,应聚焦碳减排,制定差异化的碳减排策略;利用差别税率,健全绿色税收体系;立足跨区合作,完善区域税制协调机制。

关键词：绿色税收碳排放双碳 STIRPAT模型碳减排

Targeting Epac2 and GluA3-containing AMPARs:a novel therapeutic strategy for Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3223-3224页

作者： tong Zhang Martina Schmidt Department of Molecular Pharmacology Groningen Research Institute of PharmacyUniversity of GroningenGroningenThe Netherlands School of Pharmacy Tianjin Medical UniversityTianjinChina

Alzheimer's disease(AD)is a neurodegenerative disease that manifests progressive decline in memory and *** the early stage of AD,memory retrieval is impaired preceding memory acquisition and consolidation(Roy et al.,2016).Prior to the onset of symptoms,pathological amyloid-β(Aβ)plagues and tau protein tangles accumulate in extracellular and intracellular spaces,respectively,leading to *** these hallmark pathologies,Aβ is proposed to be the primary etiology by triggering a cascade of pathogenic events,including neuroinflammation,oxidative stress,tau hyperphosphorylation,synaptic/neuronal dysfunction,and neuronal death(Zhang et al.,2023b).

关键词： Alzheimer impaired Aβ