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Potassium isotopic signatures of modern offshore detrital sediments from different climatic regimes and the implications

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science China Earth sciences 2024年第2期67卷 405-419页

作者： Jun MU Tianyu CHEN Qian YU Shichao AN Jianfang CHEN Xuefa SHI Weiqiang LI State Key Laboratory for Mineral Deposits research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Ministry of Education Key Laboratory for Coast and Island Development School of Geography and Ocean ScienceNanjing UniversityNanjing210023China State Key Laboratory of Satellite ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao266061China

Potassium isotopes are a novel tracer for continental *** K isotope studies on chemical weathering generally targeted weathering profiles under a particular climate region,yet the effects of chemical weathering on K isotopes under different climatic backgrounds remain ***,little is known about the K isotope signatures of modern unconsolidated detrital ***,we report K isotopic data of surficial seafloor sediments from continental shelves along the east coast of China(ECC),as well as those around the tropical Hainan island in the northern South China *** ECC sediments have a relatively narrow distribution ofδ^(41)K(with reference to NIST3141a)values,which range from(-0.40±0.01)‰to(-0.57±0.04)‰,with an average of(-0.51±0.09)‰.By contrast,δ^(41)K values of Hainan offshore sediments display a larger variation,ranging from(-0.28±0.07)‰to(-0.67±0.02)‰.Theδ^(41)K values of Hainan offshore sediments exhibit negative correlations with the chemical index of alteration(CIA),Al/K,Ti/K,and total iron(FeT),which underlines the control of chemical weathering on K isotopic signatures of detritus inputs into *** also measured Mg isotope compositions for the same samples;interestingly,the variability inδ^(26)Mg of the samples is small(~0.24‰)for all ECC and Hainan offshore sediments,andδ^(26)Mg values do not show clear correlations with indexes of chemical *** study demonstrates the link between K isotopic variability of detrital sediments and climatic conditions including rainfall intensity,which indicates that K isotopes of the detrital component of marine sediments could be applied to study Earth’s climate in deep ***δ^(41)K values of the offshore detrital sediments are significantly less variable than those of pelagic marine sediments,highlighting the importance of distinguishing the effects of diagenesis and neoformation of clay minerals from continental weathering in attempts to study deep-time climate-weathering

关键词： Potassium isotopes Magnesium isotopes Chemical weathering Detrital sediments Climatic regimes Mean annual precipitation

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Comparative study on the performance of ConvLSTM and ConvGRU in classification problems-taking early warning of short-duration heavy rainfall as an example

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Atmospheric and oceanic science Letters 2024年第4期17卷 52-57页

作者： Meng Zhou Jingya Wu Mingxuan Chen Lei Han Faculty of Information science and Engineering Ocean University of ChinaQingdaoChina institute of Urban Meteorology China Meteorological AdministrationBeijingChina

卷积长短期记忆单元ConvLSTM和卷积门控循环单元ConvGRU是两种广泛应用的深度学习单元,通过将循环机制与卷积运算相结合,常常用于时空序列的预测.为了明确上述两种模型的收敛速度和分类能力,需要使用相同的模型架构对相同的分类问题进... 详细信息

卷积长短期记忆单元ConvLSTM和卷积门控循环单元ConvGRU是两种广泛应用的深度学习单元,通过将循环机制与卷积运算相结合,常常用于时空序列的预测.为了明确上述两种模型的收敛速度和分类能力,需要使用相同的模型架构对相同的分类问题进行预测.本研究将北京短时强降水区级预警问题看作深度学习中的二分类问题,使用京津冀雷达网的组合反射率数据和北京区域内的自动气象站降雨数据进行深度学习模型的训练和评估.结果表明,ConvGRU的收敛速度比ConvLSTM快约25%.ConvLSTM和ConvGRU的预警性能随地区,时间,降雨强度的变化趋势相似,但大部分ConvLSTM的得分较高,少数情况下ConvGRU的得分较高.

关键词：深度学习卷积长短期记忆单元卷积门控循环单元分类问题

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A chromosome-level genome assembly of the miiuy croaker(Miichthys miiuy)using nanopore sequencing and Hi-C

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Aquaculture and fisheries 2024年第2期9卷 218-225页

作者： Tianjun Xu Ye Li Weiwei Zheng Yuena Sun Laboratory of Fish Molecular Immunology College of Fisheries and Life ScienceShanghai Ocean UniversityShanghai201306China Laboratory of Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao266200China Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources(Shanghai ocean University) Ministry of EducationShanghai201306China National Pathogen Collection Center for Aquatic Animals Shanghai Ocean UniversityShanghai201306China

Miiuy croaker,Miichthys miiuy is an ecologically important teleost species which is widely distributed in southeast coast of *** this study,we present a chromosomal-scale genome assembly of the miiuy croaker which is an important Sciaenidae fish and economical *** adopted Oxford Nanopore and Hi-C sequencing techniques to achieve an assembly with high accuracy and *** investigation of genome characteristic and functional features may provide insights into the study of phylogenetic diversity of miiuy *** study can also be beneficial to improve molecular assisted breeding ***,it can be a great resource to better conduct further study of other sciaenids.

关键词： Miiuy croaker Chromosomal assembly Genome annotation Genome evolution Phylogenetic

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Intraseasonal variability of the Kuroshio observed via mooring at 18°N

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Journal of oceanology and Limnology 2024年第2期42卷 468-483页

作者： Xin YUAN Qingye WANG Jie MA Shijian HU Dunxin HU Key Laboratory of ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of sciences Beijing 100049China Laoshan Laboratory Qingdao 266237China Center for ocean Mega-science Chinese Academy of SciencesQingdao 266071China

Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the *** measurements of the Kuroshio velocity were performed with an array of three profiler moorings(122.7°E,123°E,and 123.3°E)along 18°N from January 2018 to February *** ISV of the Kuroshio at 18°N was investigated based on a combination of mooring observations and global high-resolution HYbrid Coordinate ocean Model reanalysis *** estimated time-averaged transport in the upper 350 m across the observation transect was 6.5±2.6 Sv(1.0 Sv=10^(6)m^(3)/s).Two significant ISV peaks at 50-60 and~100 d were recognized in the power spectra of the meridional velocity and *** analysis indicated that the ISV at 50-60 d was caused by westward-propagating eddies at average propagation speed of~13 cm/s and wavelength of~635 *** ISV peak at~100 d was mainly caused by northward-propagating eddies generated in the North Equatorial Current *** investigation indicated that the ISV of the Kuroshio at 18°N is dominated by meridional transport,rather than by the zonal migration of the Kuroshio main *** findings provide a better understanding of the ISV of the Kuroshio east of Luzon Island.

关键词： intraseasonal variability(ISV) Kuroshio mooring observation eddy

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GNSS gyroscopes:determination of angular velocity and acceleration with very high-rate GNSS

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Satellite Navigation 2024年第1期5卷 74-90页

作者： Yun Shi Peiliang Xu Yuanming Shu Xiaolin Meng School of Geomatics Xi’an University of Science and TechnologyXi’an710054People’s Republic of China Disaster Prevention research institute Kyoto UniversityUjiKyoto611-0011Japan College of Marine Geosciences Ocean University of ChinaQingdaoPeople’s Republic of China School of Instrument science and Engineering Southeast UniversityNanjing210096People’s Republic of China

Although global navigation satellite systems(GNSS)have been routinely applied to determine attitudes,there exists no literature on determining angular velocity and/or angular acceleration from *** by the invention of computerized accelerometers of the correspondence author and following the success of accurately recovering translational velocity and acceleration waveforms from very high-rate GNSS precise positioning by Xu and his collaborators in 2021,we propose the concept of GNSS gyroscopes and reconstruct angular velocity and acceleration from very high-rate GNSS attitudes by applying regularization under the criterion of minimum mean squared *** major results from the experiments can be summarized in the following:(i)angular velocity and acceleration waveforms computed by applying the difference methods to high-rate GNSS attitudes are too noisy and can be physically not meaningful and numerically *** same can be said about inertial measurement unit(IMU)attitudes,if IMU gyros are not of very high accuracy;(ii)regularization is successfully applied to reconstruct the high-rate angular velocity and acceleration waveforms from 50 Hz GNSS attitudes and significantly outperforms the difference methods,validating the proposed concept of GNSS *** comparing the angular velocity and acceleration results by using the difference methods and regularization,we find that the peak values of angular velocity and acceleration by regularization are much smaller by a maximum factor of 1.57 in the angular velocity to a maximum factor of 8662.53 times in the angular acceleration in the case of high-rate GNSS,and by a maximum factor of 1.26 in the angular velocity to a maximum factor of 2819.85 times in the angular acceleration in the case of IMU,respectively;and(iii)the IMU attitudes apparently lead to better regularized angular velocity and acceleration waveforms than the high-rate GNSS attitudes,which can well be explained by the fact that the

关键词： Angular velocity Angular acceleration High-rate GNSS GNSS attitudes GNSS gyroscopes Regularization

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Expression and characterization of a novel GH128 laminarinase OUC-BsLam26 harboring both hydrolyzing and transferring activities

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Food science and Human Wellness 2024年

作者： Yueyang Dong Yongyi Quan Hong Jiang Hamed I.Hamouda Zewei Lu Yimiao Chen Chengqiang Li Xiangzhao Mao State Key Laboratory of Marine Food Processing and Safety Control， College of Food science and Engineering， ocean University of China Qingdao Key Laboratory of Food Biotechnology Sanya ocean research institute， ocean University of China Processes Design and Development Department， Egyptian Petroleum research institute Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine science and Technology Key Laboratory of Biological Processing of Aquatic Products，China National Light Industry

Laminarin oligosaccharides (LOSs) with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values. Human intestinal bacteria are promising potential producers of novel carbohydrate-active enzymes with unique properties. Here， a novel glycoside hydrolase family 128 (GH128) laminarinase OUC-BsLam26 from the intestinal bacterium Bacteroides sp. CBA7301 was heterologously expressed and characterized. The recombinant OUC-BsLam26 with a molecular mass of 49.86 kDa exhibits highest activity (6.60 U/mg) at 45 ℃ and pH 6.0， which shows noticeable temperature and pH stability. The purified OUC-BsLam26 could degrade laminarin via an endo-type mode with the generation of laminaripentaose， laminaritetraose， laminaritriose， and laminaribiose， among them， laminaritetraose is the principal product， which accounts for 45.25% of the total products， which is significantly different from the reported GH128 laminarinases. The minimum recognition substrate of OUC-BsLam26 is laminarihexaose. Furthermore， OUC-BsLam26 also could catalyze the transglycosylation process with the production of some novel glycosides. Altogether， the intestinal bacterium Bacteroides sp. CBA7301 contains laminarinase with unique product composition and OUC-BsLam26 is a hopeful bio-catalyst with the potential to produce laminaritetraose and some novel glycosides.

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The impact of typhoons on the biogeochemistry of dissolved organic matter in eutrophic bays in northwestern South China Sea

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Acta oceanologica Sinica 2024年第6期43卷 15-31页

作者： Xuan Lu Qibin Lao Fajin Chen Guangzhe Jin Chunqing Chen Qingmei Zhu College of ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China Polar and Marine research institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China Key Laboratory for Coastal ocean Variation and Disaster Prediction Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep SeaDepartment of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China

Highly productive estuaries facilitate intense decomposition of dissolved organic matter(DOM) as a carbon ***,the specific impacts of typhoons on DOM decomposition in eutrophic bays remain *** address this issue,we investigated the spectral characteristics of DOM before and after Typhoon Ewiniar in Zhanjiang B ay,a eutrophic semi-enclosed bay in the northwestern South China *** results revealed that intense microbial decomposition of DOM occurred during the pre-typhoon period because high nutrient inputs facilitated the mobilization of DOM in the ***,the intrusion of external seawater induced by the typhoon diluted the nutrient levels in Zhanjiang B ay,reducing the impact of microbial decomposition on DOM during the post-typhoon perio ***,the net addition of DOM occurred in Zhanjiang Bay during the post-typhoon period,possibly because of the decomposition of particulate organic matter(POM) and desorption of particulate *** addition,an increase in apparent oxygen utilization,a decrease in DO saturation and the reduced level of Chl a indicated that organic matter(OM) decomposition was enhanced and OM decomposition shifted to POM decomposition in Zhanjiang Bay after the ***,our study highlighted the shift in the intense OM decomposition from DOM to POM decomposition before and after typhoons in eutrophic bays,providing new insights into the response of typhoons to biogeo chemistry.

关键词： dissolved organic matter optical analyses decomposition typhoon northwestern South China Sea

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Satellite observations of coastal upwelling in the northern Arafura Sea

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Journal of oceanology and Limnology 2024年第2期42卷 361-376页

作者： Zheyuan YU Zhanjiu HAO Zhenhua XU Peiwen ZHANG Jia YOU Baoshu YIN Hongwei YANG College of Mathematics and System science Shandong University of Science and TechnologyQingdao 266590China CAS Key Laboratory of ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Pilot National Laboratory for Marine science and Technology(Qingdao) Qingdao 266237China Center for ocean Mega-science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of sciences Beijing 100049China CAS Engineering Laboratory for Marine Ranching Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary *** satellite observations show that the northern Arafura Sea(NAS),especially in the coastal region,features high chlorophyll-a(chl-a)concentrations,implying a strong coastal ***,coastal upwelling in the NAS has not received much *** on a semi-automatic image processing technology,the seasonal and interannual variability of coastal upwelling in the NAS are investigated in this study using satellite-observed sea surface temperature(SST)and wind *** results suggest that there are seasonal coastal upwelling events in the NAS modulated by upwelling-favorable southeast monsoon(SEM).The annual mean days,mean area,and annual mean intensity of coastal upwelling events during the SEM season are 92 days,6514 km^(2),and-5.31×10^(5),respectively,while the corresponding values during the northwest monsoon(NWM)season are 32 days,5569 km^(2),and-1.41×10^(5).It is also found that the SEM coastal upwelling in the NAS displays prominent interannual *** strong upwelling events are found in 2010,2013,2016,and 2017 when the southeast monsoon winds were *** analysis suggests that at the interannual scale,the upwelling index(UI)averaged in the SEM season is negatively correlated with that of three upwelling *** can be attributed to the limitation of onshore geostrophic flow which is evidenced by the negative correlation between the UI and the alongshore difference in sea surface *** study highlights the important role of the southeast monsoon in the temporal variability of coastal upwelling in the NAS.

关键词： coastal upwelling the northern Arafura Sea southeast monsoon interannual variability

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Temperate Stutzerimonas Phage Encoding Toxin-Antitoxin System Genes Represents a Novel Genus

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Journal of ocean University of China 2024年第4期23卷 1087-1101页

作者： ZHANG Hong GUO Ruizhe GAO Chen ZHENG Kaiyang XIONG Yao DONG Yue LIU Yundan WANG Ziyue CHEN Ying WANG Hongmin SHAO Hongbing SUNG Yeong Yik MOK Wen Jye WONG Li Lian MCMINN Andrew WANG Min LIANG Yantao College of Marine Life sciences Institute of Evolution and Marine BiodiversityMOE Laboratory of Evolution and Marine BiodiversityFrontiers Science Center for Deep Ocean Multispheres and Earth SystemCenter for Ocean Carbon NeutralityOcean University of ChinaQingdao 266003China UMT-OUC Joint Center for Marine Studies Qingdao 266003China institute of Marine Biotechnology Universiti Malaysia Terengganu21030 Kuala TerengganuMalaysia institute for Marine and Antarctic Studies University of TasmaniaHobartTAS 7001Australia Haide College Ocean University of ChinaQingdao 266100China The Affiliated Hospital of Qingdao University Qingdao 266001China

Stutzerimonas have been extensively studied due to their remarkable metabolic and physiological ***,research on its phages is currently *** this study,we isolated a novel double-stranded DNA(dsDNA)phage,vB_SstM-PG1,from the marine environment that infects Stutzerimonas stutzeri *** dsDNA genome is 37204 bp long with a G/C content of 64.14%and encodes 54 open reading *** phage possesses a tail packaging structure that is different from known Stutzerimonas stutzeri phages and exhibits structural protein characteristics similar to those of temperate *** addition,two genes of toxin-antitoxin system,including YdaS_antitoxin and HEPN_SAV_6107,were found in the vB_SstM-PG1 genome and play important roles in regulating host growth and *** phylogenetic tree and comparative genomic analysis,it has been determined that vB_SstM-PG1 is not closely related to any phages previously identified in the GenBank ***,it has a connection with enigmatic,uncultured ***,the vB_SstM-PG1 virus exhibits an average nucleotide identity of over 70%with six uncultivated viruses identified in the IMG/VR v4 *** significant finding has resulted in the identification of a novel viral genus known as Metabovirus.

关键词： Stutzerimonas vB_SstM-PG1 Metabovirus temperate phage genomic and phylogenetic analysis

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Development of underwater electric manipulator based on interventional autonomous underwater vehicle (AUV)

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2024年第3期25卷 238-250页

作者： Xiaohui HU Jiawang CHEN Hang ZHOU Ziqiang REN ocean cllege Zhejiang UniversityZhoushan 316021China Hainan institute Zhejiang UniversitySanya 572025China The Engineering research Center of oceanic Sensing Technology and Equipment Ministry of EducationZhoushan 316021China

In applications such as marine rescue,marine science,archaeology,and offshore industries,autonomous underwater vehicles(AUVs)are frequently used for survey missions and monitoring tasks,with most operations being performed by manned submersibles or remotely operated vehicles(ROVs)equipped with robotic arms,as they can be operated remotely for days without ***,they require expensive marine vessels and specialist pilots to operate *** exploring oceans are no longer satisfied with the use of manned submersibles and *** is a growing desire for seabed exploration to be performed using smarter,more flexible,and automated *** improving the field operation and intervention capability of AUVs,large-scale and long-range seafloor exploration and sampling can be performed without the support of a mother ship,making it a more effective,economical,convenient,and rapid means of seafloor exploration and sampling operations,and playing a critical role in marine resource *** this study,we explored the integration technology of underwater electric robotic arms and AUVs and designed a new set of electric manipulators suitable for water depths greater than 500 *** reliability of the key components was analyzed by finite element analysis and,based on the theory of robot kinematics and dynamics,simulations were performed to verify the reliability of the key *** were conducted on land and underwater,trajectory tracking experiments were completed,and the experimental data in air and water were compared and ***,the objectives for further research on the autonomous control of the manipulator underwater were proposed.

关键词： Underwater electric manipulator Inverse kinematics Trajectory planning Trajectory tracking accuracy

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