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Isobaric enzymatic assays reveal depth-dependent variation in microbial ectoenzyme activities in the deepest ocean on Earth

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Science China Earth Sciences 2025年第1期68卷 185-194页

作者： Junwei CAO Jiahua WANG Hongge ZHANG Junhao DENG Binbin PAN Jiawang CHEN Li ZHANG Jiasong FANG College of Oceanography and Ecological Science Shanghai Ocean University Ocean College Zhejiang University laboratory for marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology

Microbial ectoenzymes play essential roles in the transformation and mineralization of organic matter in the ***, conventional methods for measuring microbial ectoenzyme activities(MEAs) in the deep ocean under atmospheric conditions can misrepresent the metabolic activities of indigenous microbial communities. To overcome this limitation, we measured the activities of three microbial ectoenzymes(aminopeptidase, α-glucosidase, and β-glucosidase) under both atmospheric and in situ pressure conditions in seawater collected using pressure-retaining and non-pressure-retaining samplers in the Challenger Deep, Mariana Trench. In the case of aminopeptidase and α-glucosidase, the highest isobaric MEAs were observed in the surface layer(50 m), followed by those at abyssopelagic depths(4,000–6,000 m) for aminopeptidase, hadal realm(10,903 m)for α-glucosidase, while β-glucosidase activity exhibited the highest value at 10,903 m. Furthermore, the isobaric MEAs in hadal waters were commonly found to be higher than the decompressed counterparts, highlighting the importance of pressure-retaining sampling and isobaric enzymatic assays. The half-saturation constant(Km) showed a general decreasing trend with depth,suggesting that the deep ocean microbes might have adapted to the high-pressure and oligotrophic environment by increasing their ectoenzyme's affinity to substrate. Furthermore, particle-free MEAs contribute more to the total MEAs in the deep ocean than particle-associated MEAs, suggesting the significance of cell-associated and dissolved ectoenzymes in ocean *** study provides a foundation for future investigations of MEAs in the ocean and has important implications for understanding the dynamics of microbially mediated biogeochemical cycling in marine ecosystems.

关键词： Pressure-retaining sampling Microbial ectoenzyme activity Deep-sea microbes High pressure Mariana Trench

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Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期34卷 303-322页

作者： JU Dehao LIU Rui ZHENG Liang DENG Jiahui ZHANG Wenzheng HUO Jinlu HUANG Li Shanghai marine Diesel Engine Research Institute National Key laboratory of marine Engine Science and Technology Key laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with X-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

关键词： atomization dual-orifice nozzle nozzle structure spray flame asymmetry

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Genes and proteins expressed at different life cycle stages in the model protist Euplotes vannus revealed by both transcriptomic and proteomic approaches

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Science China Life Sciences 2025年第1期68卷 232-248页

作者： Yaohan Jiang Xiao Chen Chundi Wang Liping Lyu Saleh A.Al-Farraj Naomi A.Stover Feng Gao Key laboratory of Evolution & marine Biodiversity (Ministry of Education) and Institute of Evolution & marine Biodiversity Ocean University of China marine College Shandong University Zoology Department College of ScienceKing Saud University Department of Biology Bradley University laboratory for marine Biology and Biotechnology Qingdao Marine Science and Technology Center

Sexual reproduction first appeared in unicellular protists and has continued to be an essential biological process in almost all *** protists, which contain both germline and somatic genomes within a single cell, have evolved a special form of sexual reproduction called conjugation that involves mitosis, meiosis, fertilization, nuclear differentiation, genome rearrangement, and the development of unique cellular structures. The molecular basis and mechanisms of conjugation vary dramatically among ciliates, and many details of the process and its regulation are still largely unknown. In order to better comprehend these processes and mechanisms from an evolutionary perspective, this study provides the first comprehensive overview of the transcriptome and proteome profiles during the entire life cycle of the newly-established marine model ciliate Euplotes vannus. Transcriptome analyses from 14 life cycle stages(three vegetative stages and 11 sexual stages) revealed over 26,000 genes that are specifically expressed at different stages, many of which are related to DNA replication,transcription, translation, mitosis, meiosis, nuclear differentiation, and/or genome rearrangement. Quantitative proteomic analyses identified 338 proteins with homologs associated with conjugation and/or somatic nuclear development in other ciliates, including dicer-like proteins, Hsp90 proteins, RNA polymerase Ⅱ and transcription elongation factors, ribosomal-associated proteins, and ubiquitin-related proteins. Four of these homologs belong to the PIWI family, each with different expression patterns identified and confirmed by RT-qPCR,which may function in small RNA-mediated genome rearrangement. Proteins involved in the nonhomologous end-joining pathway are induced early during meiosis and accumulate in the developing new somatic nucleus, where more than 80% of the germline sequences are eliminated from the somatic genome. A number of new candidate genes and proteins likely t

关键词： sexual reproduction transcriptomic proteomic genome rearrangement PIWI NHEJ

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Propagating subduction initiation of the Caroline Plate at the Mussau Trench

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Science China Earth Sciences 2025年第1期68卷 253-269页

作者： Chun-Feng LI Yongkang DENG Tao WU Dongdong DONG Guoliang ZHANG Jiazheng ZHANG Yutao LIU Yaqing LI Fugui TANG Lulu ZHANG Department of marine Sciences Zhejiang University laboratory of marine Mineral Resources Laoshan Laboratory Key Lab of marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Key Lab of Ocean and Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Science & Technology on Integrated Information System Lab Institute of Software Chinese Academy of Sciences

New seismic imaging from the Mussau Trench confirms that, under horizontal compression on an oceanic plate boundary, it is within the young and weak oceanic plate that a trench will develop, and it is the young plate, not so long after its birth, that starts to subduct toward the old plate. The Mesozoic Pacific Plate cannot easily bend, under the joint horizontal compression and vertical gravity pull, even with a pre-existing weak zone in place and with a large age offset across the plate boundary. The bending of the Caroline Plate near the northern end of the Mussau Trench started only after a long-time span of trench migration, and/or after a prolonged transition from initial compression to trench development. Highly contrasting trench deformation and sedimentary accretion between two parallel seismic sections support an evident migration of underthrusting or significant longitudinal heterogeneity along the trench. The swift transition from underthrusting to non-thrusting can be explained by a counter-clockwise rotation of the Caroline Plate. That miniature accretionary wedges develop even before the subduction initiates imply strong compression and uplifting before the underthrusting can kick-start. Rotation of the Caroline Plate have been halted as the Mussau Trench is seismically rather quiet and the Lyra Trough to the east shows relaxational extension.

关键词： Mussau Trench Subduction initiation Seismic reflection Caroline Plate

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Sr-Nd isotopic characteristics and their significance in provenance tracing of detrital sediment in major rivers and marginal seas of eastern China

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Science China Earth Sciences 2025年

作者： Xiaobao GAO Chao LI Zhifei DUAN Yulong GUO Shouye YANG State Key laboratory of marine Geology Tongji University

Sr-Nd isotopes are widely utilized as reliable tracers in sediment provenance *** this study,we compiled 304Sr and 335 Nd isotope data of fine-grained surface sediments collected from major rivers in eastern China,including the Huanghe River,Changjiang River,southeastern coastal rivers,and rivers in Taiwan Island,as well as from marginal seas （Yellow Sea and East China Sea） and the Okinawa *** comprehensive dataset allowed us to examine the spatial distribution patterns of these isotopes and their implications for provenance *** variations of εNd values in the sediments in Changjiang and Huanghe Basins primarily reflect the diversity of sediment sources,whereas the87Sr/86Sr ratios are influenced by both grain size and source ***,the reduction in87Sr/86Sr ratios observed in the middle and lower Changjiang River is attributed to the inputs of sources characterized by distinct87Sr/86Sr signatures beyond mere grain size *** the southeastern coastal and Taiwan rivers,sediments in the tidal reaches of the Jiao River exhibit hybrid characteristics,a mix of Changjiang-derived sediment and those originating from local ***,the Min River and Jiulong River sediments predominantly reflect local sources,with minimal influence from the Changjiang *** significant isotopic variation of Sr-Nd isotopic characteristics observed between riverine sediments on the eastern and western sides of Taiwan Island underscores the diverse provenance heterogeneity of source rocks in the *** the marginal seas,our data indicates that the surface sediments in the central mud area of the South Yellow Sea and the southern Yellow Sea are predominantly sourced from the Changjiang River catchment,potentially augmented by inputs from Korean *** inner shelf sediments of the East China Sea are primarily influenced by Changjiang River inputs,whereas rivers in eastern Taiwan Island contribute to the sediments on the middle and

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Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu Xiao Wei Xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key laboratory of marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

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An Enhanced Dual-Layer Ensemble Framework for Porosity Prediction Utilizing Conventional Well Logging Data

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Journal of Earth Science 2025年

作者： Lu Qiao Shengyu Yang Qinhong Hu Huijun Wang Taohua He National Key laboratory of Deep Oil and Gas， China University of Petroleum (East China) laboratory for marine Mineral Resources， Qingdao National laboratory for marine Science and Technology Hubei Key laboratory of Petroleum Geochemistry and Environment (Yangtze University)， Yangtze University

Porosity is the one of the most fundamental and critical parameters for reservoir characterization and is closely related to the hydrocarbon storage capacity. The interpretation methods of conventional well logs have poor generalization capabilities to achieve the desired accuracy in porosity prediction. The increasing adoption of machine learning has ameliorated this predicament to some extent， but it remains difficult to reconstruct the complex and nonlinear relationship between logging responses and porosity by relying on individual machine learning models alone. This work proposes a two-layer model ensemble framework to predicte porosity， which includes base regressors in the first layer and meta regressor in the second layer. The results indicate that the Light Gradient Boosting Machine (LightGBM) - Categorical-Features Gradient Boosting (CatBoost) ensemble model provides the highest prediction accuracy for the given dataset and is applied for porosity evaluation at other logged depths. This work also points out that the base regressor should be accurate and complex， while the structure of the meta-regressor should be simple in order to achieve the desired performance. Furthermore， the proposed model ensemble framework is versatile and applicable to reservoir evaluation， engineering development， and other potential fields due to its effectiveness and convenience.

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Innovative dual-mode device integrating capacitive desalination and solar vapor generation for high-efficiency seawater desalination

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Journal of Energy Chemistry 2025年第1期100卷 171-179页

作者： Jiacheng Wang Zhaoyu Chen Ruduan Yuan Jiaxin Luo Ben Zhang Keju Ji Meng Li Juanxiu Xiao Kuan Sun National Innovation Center for Industry-Education Integration of Energy Storage Technology MOE Key Laboratory of Low-grade Energy Utilization Technologies and SystemsCollege of Energy & Power Engineering Chongqing University Xuefeng Mountain Energy Equipment Safety National Observation and Research Station CQU-NUS Renewable Energy Materials & Devices Joint Laboratory Chongqing University Southwest Technology and Engineering Research Institute Jiangsu Provincial Key laboratory of Bionic Functional Materials College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics State Key laboratory of marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University

Solar-driven interface evaporation with high solar-to-steam conversion efficiency has shown great potential in seawater ***,due to the influence of latent heat and condensation efficiency,the water yield from solar-driven interface evaporation remains insufficient,posing a significant challenge that requires *** this work,we designed a dual-mode high-flux seawater desalination device that combines solar-driven interface evaporation and capacitive *** utilizing coupled desalination materials exhibiting both photothermal conversion and capacitance activity,the device demonstrated photothermal evaporation rates of 1.41 and 0.97 kg m-2h-1for condensate water yield under one-sun ***,the device exhibited a salt adsorption capacity of up to48 mg g-1and a salt adsorption rate of 2.1 mg *** addition,the salt adsorption capacity increased by approximately 32% under one-sun ***,photo-enhanced capacitive desalination performance was explored through numerical simulations and theoretical *** calculations and characterizations confirmed that the defect energy levels formed by the introduction of sulfur vacancies can effectively widen the light absorption range,improve photothermal conversion performance,and stimulate more photoelectrons to participate in capacitive ***,the electron distribution state of molybdenum disulfide with sulfur vacancies and surface defect sites contributes to ion/electron transport at the solid-liquid *** work provides a novel pathway for integrating solar vapor generation with other low-energy desalination technologies.

关键词： Desalination

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Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 204-214页

作者： WANG Tao FAN Xiangqian GAO Changsheng QU Chiyu The National Key laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China Southern marine Science and Engineering Guangdong laboratory(Guangzhou) Guangzhou 511458China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We have described in detail the effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca(OH)2 to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.The optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.The optimum content of carbon nanotubes is between 0.1%and 0.2%.The optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mechanics microstructure

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A robust statistical prediction model for late-summer heavy precipitation days in North China

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Science China Earth Sciences 2025年第1期68卷 158-171页

作者： Shunli JIANG Tingting HAN Xin ZHOU Huijun WANG Zhicong YIN Xiaolei SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key laboratory of Meteorological Disaster Ministry of Education Nanjing University for Information Science and Technology Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Southern marine Science and Engineering Guangdong laboratory (Zhuhai)

Recently, heavy precipitation(HP) events have occurred frequently in North China(NC), causing devastating economic losses and human fatalities. However, the short-term climate prediction of HP is quite limited. Combining year-to-year increment(DY) method and sliding correlations, we developed a robust seasonal prediction model for late-summer HP days(HPDs) in NC during 1982–2022, utilizing three independent predictors—February sea surface temperature(SST) in the Indian Ocean(SST＿IO), February snow depth over North Asia(SDE＿NA), and May melted snow depth in NC(MSDE＿NC). The SST＿IO anomalies affect NC's precipitation through the Pacific-Japan pattern. The SDE＿NA anomalies are associated with East Asian anomalous anticyclone by southeastern propagation of Rossby wave at Eurasia. The MSDE＿NC anomalies are followed by vertical motion and moisture anomalies in situ and thereby cause precipitation anomalies. This prediction model can well simulate the variations of the HPDs, with a correlation coefficient(CC) of 0.81(0.65) between the observed and predicted HPDs＿DY(HPDs＿anomaly). The percentage with the same sign for 15 extreme HPDs＿anomaly years(PSSE) is 100%.Moreover, in the cross-validation test during 1982–2022, the PSSE for HPDs＿anomaly is as high as 100%, along with a low rootmean-square error of 1.14. For independent hindcasts during 2013–2022, the CC between the observed and predicted HPDs＿DY(HPDs＿anomaly) is 0.93(0.83), together with high Nash-Sutcliffe efficiency(0.82) and agreement index(0.89). Specifically, the predictions are broadly consistent with the observations for 2015, 2016, 2017, 2021, and 2022, reflecting excellent performance of this prediction model of HPDs in NC.

关键词： Heavy precipitation at North China Year-to-year increment approach Robust seasonal prediction Sea surface temperature Snow depth

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