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二种核糖体型的多环马格里夫藻(Margalefidinium polykrikoides)的形态和超微结构比较及分子系统学分析

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海洋与湖沼 2019年第6期50卷 1252-1262页

作者：翟噎宇邓蕴彦孙园园 LEAW Chui-Pin LIM Po-Teen 赵增霞胡章喜唐赢中中国科学院海洋生态与环境科学重点实验室中国科学院海洋研究所中国科学院大学青岛海洋科学与技术试点国家实验室海洋生态与环境科学功能实验室中国科学院海洋大科学研究中心中国科学院实验海洋生物学重点实验室中国科学院海洋研究所 Bachok Marine Research Station Institute of Ocean and Earth Sciences University of Malaya 中国科学院海洋研究所胶州湾海洋生态系统国家野外科学观测研究站

多环马格里夫藻是一种世界性广泛分布的有毒有害藻华原因种。过去30多年里多环马格里夫藻藻华在许多国家频繁暴发且呈快速扩散趋势。过去的研究根据不同地理来源种群在核糖体大亚基基因序列的显著差别,将其分成4种不同核糖体型(ribotyp... 详细信息

多环马格里夫藻是一种世界性广泛分布的有毒有害藻华原因种。过去30多年里多环马格里夫藻藻华在许多国家频繁暴发且呈快速扩散趋势。过去的研究根据不同地理来源种群在核糖体大亚基基因序列的显著差别,将其分成4种不同核糖体型(ribotype),即东亚型、菲律宾型、美国/马来西亚型和地中海型。但是,不同核糖体型的种群在形态和超微结构上是否也存在可辨识差异尚未见深入研究。为此,本文对从中国青岛胶州湾、美国东海岸和马来西亚近海分离的三株多环马格里夫藻(中国株MPJZBC3、美国株CP1和马来西亚株MPCoKK23)的细胞表面形态和超微结构进行了比较研究,并进一步基于核糖体大亚基序列进行了分子系统学分析。结果首先证明了分离自胶州湾的多环马格里夫藻属于东亚核糖体型,而美国株和马来西亚株均属美国/马来西亚型(中国株与美国株及马来西亚株在1523个碱基的核糖体大亚基序列上相似性为93.6%)。但是,在所有常用的具有分类学意义的细胞形态学和超微结构特征上[细胞大小、单细胞或群体及群体细胞数、上下锥形状、横沟位移度(绕细胞圈数)、纵沟形态、顶沟形态、细胞核位置与形状、染色体形状与数目、叶绿体的形状、结构、数目及分布、淀粉核形态等],中国株与美国株和马来西亚株(也即东亚核糖体型和美国/马来西亚核糖体型)都没有明显可区分的差别。因此,我们认为应该在生活史、休眠孢囊形态和生理学特征(如毒素种类及毒性强弱)以及性别相容性(sexual compatibility)等方面开展进一步比较研究,以获得对不同核糖体型种群的识别性状。在现阶段有害藻华的野外监测中,尤其是对于不同核糖体型种群可能造成的生物入侵的监测和追溯,多环马格里夫藻的鉴定尚必须以核糖体基因序列作为可靠的判决依据。

关键词：多环马格里夫藻核糖体型表面形态超微结构系统进化

Optimization strategy in end milling process for high speed machining of hardened die/mold steel

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Journal of University of Science and Technology Beijing 2006年第3期13卷 240-243页

作者： ying tang Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

An optimization strategy for high speed machining of hardened die/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed. Constraints to satisfy specific machining strategies when high speed machining the hardened die/mold steel, trochoid tool path pattern in slot end milling to avoid over-heat and feed rate adaptation to avoid over-load, were also discussed. As a case study, the tool selection problem when machining a die part with multiple machining features was investigated.

关键词： optimization algorithm hardened die/mold steel machining cost machining feature

Early life migration and population discrimination of the small yellow croaker Larimichthys polyactis from the Yellow Sea: inferences from otolith Sr/Ca ratios

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Journal of Oceanology and Limnology 2022年第2期40卷 818-829页

作者： Dade SONG ying XIONG Tao JIANG Jian YANG Xiaming zhong Jianhua tang College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Jiangsu Marine Fisheries Research Institute Nantong 226007China Key Laboratory of Fishery Ecological Environment Assessment and Resource Conservation in Middle and Lower Reaches of Yangtze River Freshwater Fisheries Research CenterChinese Academy of Fishery SciencesWuxi 214081China

The small yellow croaker Larimichthys polyactis is a benthic marine fish species of high ecological and commercial importance and is widely distributed in the northwestern Pacifi c Ocean,especially in the Chinese coastal waters of the Bohai,Yellow,and East China *** a highly migratory species,the whole life migration of *** has been intensively ***,knowledge about its early life migration is scarce,and population divisions are inconsistent,limiting the ability of fishery scientists and administrators to evaluate the design and potential benefits of thorough conservation and resource-management *** the present study,otolith Sr/Ca was analyzed to investigate the early migratory patterns and discriminate the populations of *** in the Yellow Sea,including two spawning groups and one overwintering *** variation in Sr/Ca ratios of ontogenetic growth zones,including the nucleus(N),larval(L),metamorphosis(M),juvenile(J),and edge(E)zones,was measured by electron probe *** variation in Sr/Ca ratios in early developmental growth zones was generally characterized by an evident downward trend from the N to J zone,which suggests that the early migratory pattern of *** might be from inshore to nearshore *** discriminant analysis,based on the otolith Sr/Ca ratios of the N,L,M,and J zones,allowed the successful discrimination of the two populations,namely,the northern and southern Yellow Sea groups,whose diff erences were mainly reflected in the L and J *** with previous studies,the traditional geographic boundaries(34°N)separating these two populations might be moving *** application of otolith Sr/Ca ratios based on ontogenetic stage could improve our understanding of the migration and population discrimination of *** from the Yellow Sea.

关键词： otolith microchemistry Larimichthys polyactis early life migration population discrimination the Yellow Sea

Strategyproof Facility Location with Limited Locations

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Journal of the Operations Research Society of China 2023年第3期11卷 553-567页

作者： zhong-Zheng tang Chen-Hao Wang Meng-Qi Zhang ying-Chao Zhao School of Science Beijing University of Posts and TelecommunicationsBeijing100876China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai519087GuangdongChina BNU-HKBU United International College Zhuhai519087GuangdongChina Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Caritas Institute of Higher Education Hong Kong999077China

We study the mechanism design of facility location *** problem is to design mechanisms to select a set of locations on which to build a set of facilities,aiming to optimize some system objective and achieve desirable properties based on the strategic agents'*** agents might have incentives to misreport their private locations,in order to minimize the costs(i.e.,the distance from the closest facility).We study the setting with limited locations,that is,the facilities can only be built on a given finite set of candidate locations,rather than the whole *** locating a single facility and two facilities on a real line,we propose strategyproof mechanisms with tight approximation ratios,under the objectives of minimizing the total cost and the maximum ***,we consider the problem of locating an obnoxious facility from which the agents want to stay as far away as possible,and derive tight bounds on the approximation ratio of strategyproof mechanisms.

关键词： Mechanism design Facility location Social choice

Solid-state photoinduced luminescence switch and its advanced optical applications

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Science China Chemistry 2018年第4期61卷 377-378页

作者： Ben zhong tang Department of Chemistry The Hong Kong University of Science & Technology

Spiropyran（SP）and its derivatives were one of the earliest and most extensive systems in organic photochromic ***,the distinct absorption changes will occur during the structural isomerization from SP to merocyanine... 详细信息

关键词：光开关固态应用衍生物光反应异构化

Photosynthetic response of floating Ulva prolifera to diurnal changes of in-situ environments on the sea surface

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Journal of Oceanology and Limnology 2019年第2期37卷 589-599页

作者： ZHAO Xinyu tang Xuexi HU Shunxin zhong Yi QU Tongfei WANG ying College of Marine Life Sciences Ocean University of China Qingdao 266003 China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China

During yellow sea green tide outbreak, the thalli of Ulva prolifera drifted more than 350 km on the sea surface from off shore of Jiangsu Province to Qingdao city, where they were exposed to complex changes of local environments. The purpose of this study is to investigate the response of the thalli to diurnal changes of environments on the sea surface, and a sea surface environment simulator (SSES) was designed to simulate the natural environment of floating U . prolifera mat. A control experiment is designed in the laboratory, which was processed under suitable conditions (20°C for temperature, 72 μmol photons/(m 2 ·s) for light intensity and 30 for salinity), and an in-situ research was conducted to study the photosynthetic responses of floating U . prolifera to diurnal changes of environments. The results show that the photosynthetic efficiency of the thalli decreased gradually with time, and decreased rapidly after 14:00 local time (LT). After exposed to the environment on the sea surface for 6 h, the photosynthetic activity of the thalli decreased significantly. Furthermore, physiological-level and molecular-level experiments revealed that non-photochemical quenching (NPQ), cyclic electron flow (CEF) and energy redistribution between PSI and PSII all played an important role in the strong photosynthetic plasticity of U . prolifera . NPQ is the most important photoprotective responses to environmental changes before 12:00 LT. The results also confirmed that the CEF and energy redistribution between PSI and PSII are the main synergistic eff ects for the thalli to adapt to the environmental changes when the process NPQ cannot work. And the result can further reveal the reason why U . prolifera can adapt to the living condition of long distance drift on the sea surface. The findings of this research could provide a theoretical basis for explaining outbreaks of the green tide and instructing the management of the problem.

关键词： photosynthetic system floating Ulva prolifera diurnal change photosynthetic plasticity

Binaural Speech Separation Algorithm Based on Long and Short Time Memory Networks

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Computers, Materials & Continua 2020年第6期63卷 1373-1386页

作者： Lin Zhou Siyuan Lu Qiuyue zhong ying Chen Yibin tang Yan Zhou School of Information Science and Engineering Southeast UniversityNanjing210096China Department of Psychiatry Columbia University and NYSPINew York10032USA College of Internet of Things Engineering Hohai UniversityChangzhou213022China

Speaker separation in complex acoustic environment is one of challenging tasks in speech *** practice,speakers are very often unmoving or moving slowly in normal *** this case,the spatial features among the consecutive speech frames become highly correlated such that it is helpful for speaker separation by providing additional spatial *** fully exploit this information,we design a separation system on Recurrent Neural Network(RNN)with long short-term memory(LSTM)which effectively learns the temporal dynamics of spatial *** detail,a LSTM-based speaker separation algorithm is proposed to extract the spatial features in each time-frequency(TF)unit and form the corresponding feature ***,we treat speaker separation as a supervised learning problem,where a modified ideal ratio mask(IRM)is defined as the training function during LSTM *** show that the proposed system achieves attractive separation performance in noisy and reverberant ***,during the untrained acoustic test with limited priors,e.g.,unmatched signal to noise ratio(SNR)and reverberation,the proposed LSTM based algorithm can still outperforms the existing DNN based method in the measures of PESQ and *** indicates our method is more robust in untrained conditions.

关键词： Binaural speech separation long and short time memory networks feature vectors ideal ratio mask

Blooms of Prorocentrum donghaiense reduced the species diversity of dinoflagellate community

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Acta Oceanologica Sinica 2020年第4期39卷 110-119页

作者： Huan Wang Zhangxi Hu Zhaoyang Chai Yunyan Deng Zifeng Zhan ying zhong tang CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Most of reported harmful algal blooms(HABs)of microalgae(75%)have been caused by *** on the negative effects of HABs have generally focused on animals,valuable organisms in particular,and environmental factors such as dissolved oxygen and nutrients,but relatively fewer on community level,particularly that using metagenomic *** this study,we reported an investigation on the effects of a HAB caused by the dinoflagellate Prorocentrum donghaiense on the species diversity and community structure of the dinoflagellate sub-community via a pyrosequencing approach for the samples taken before,during,and after the bloom season of *** in the East China *** sequenced partial 28S rRNA gene of dinoflagellates for the field samples and evaluated the species richness and diversity indices of the dinoflagellate community,as a sub-community of the total *** obtained 800185 valid sequences(categorized into 560 operational taxonomic units,OTUs)of dinoflagellates from 50 samples and found that the biodiversity of dinoflagellate community was significantly reduced during the blooming period in comparison to that in pre-and after-blooming periods,as reflected in the four diversity indices:the species richness expressed as the number of OTUs,Chao1 index,Shannon index(evenness),and Gini-Simpson *** four indices were all found to be negatively correlated to the cell density of the bloom species *** analyses also revealed that the *** cell abundance was correlated negatively with NO3--N,and NO2--N,but positively with total nitrogen(TN)and total phosphorus(TP).Principal coordinates analysis(PCoA)showed that the community structure of dinoflagellates was markedly different among the different sampling periods,while the redundancy analysis(RDA)revealed *** abundance,salinity,NO3--N,and SiO32-were the most four significant factors shaping the dinoflagellate community *** results toget

关键词： Prorocentrum donghaiense dinoflagellate community diversity pyrosequencing East China Sea

Interactive effect of minerals on complex ore flotation: A brief review

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 571-583页

作者： Wan-zhong Yin Yuan tang School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Froth flotation is the most effective industrial method used to separate fine-grained minerals. The main problem of complex ore flotation is the negative effect of interactions among minerals in slurry, leading to variation in surface properties during separation. In this review,studies on the interactive effect among minerals on the flotation of iron ores, magnesite ores, and scheelite ores are summarized, and the main problems and mechanisms that diminish the separation efficiency of minerals are revealed in detail. Recent research progress on the flotation of these ores has confirmed that mineral aggregation, coating, and dissolution, as well as other factors caused by interacting behavior, explain the depressing effects of fine particles on mineral separation. Solvable methods for these effects are further discussed. Novel flotation processes and more selective reagents are critical for further investigations on various approaches to improve the beneficiation efficiency of these *** review aims to provide a good reference for conducting studies related to complex ore flotation.

关键词： interactive effect flotation iron ores magnesite ores scheelite ores