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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate

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Forest Ecosystems 2024年第2期11卷 184-192页

作者： Zhengchao Ren lei liu Fang Yin Xiaoni liu School of Earth Science and Resources Chang’an UniversityXi’an710054China Research Center of Ecological Construction and Environmental Conservation in Gansu Province Gansu Agricultural UniversityLanzhou730070China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China School of Land Engineering Chang’an UniversityXi’an710054China College of Pratacultural Science Gansu Agricultural UniversityLanzhou730070China

Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention ***,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate *** this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation *** achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV *** find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and ***,we observe an unexpected transition between tundra and savanna despite their geographical *** shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each ***,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing *** spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.

关键词： Potential natural vegetation Global warming Vegetation classification Predicted model CSCS

Engineering the future cereal crops with big biological data:toward intelligence-driven breeding by design

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Journal of Genetics and Genomics 2024年第8期51卷 781-789页

作者： lei liu Jimin Zhan Jianbing Yan National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubei 430070China

How to feed 10 billion human populations is one of the challenges that need to be addressed in the following decades,especially under an unpredicted climate *** breeding,initiating from the phenotype-based selection by local farmers and developing into current biotechnology-based breeding,has played a critical role in securing the global food ***,regarding the changing environment and ever-increasing human population,can we breed outstanding crop varieties fast enough to achieve high productivity,good quality,and widespread adaptability?This review outlines the recent achievements in understanding cereal crop breeding,including the current knowledge about crop agronomic traits,newly developed techniques,crop big biological data research,and the possibility of integrating them for intelligence-driven breeding by design,which ushers in a new era of crop breeding practice and shapes the novel architecture of future *** review focuses on the major cereal crops,including rice,maize,and wheat,to explain how intelligence-driven breeding by design is becoming a reality.

关键词： Crop Big biological data Multi-omic Artificial intelligence Crop design breeding

Early Triassic Silicic Volcanics of South China:Petrogenesis and Constraints on the Geodynamic Evolution of the Paleo-Tethys Ocean Region

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 617-629页

作者： WANG Yabo liu lei ZHAO Zengxia liu Xijun HUANG Wenmin Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration College of Earth SciencesGuilin University of TechnologyGuilinGuangxi 541004China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources Guilin University of TechnologyGuilinGuangxi 541004China

The only occurrence of Lower Triassic silicic volcanic rocks within the South China Block is in the Qinzhou Bay area of Guangxi ***-ICP-MS zircon U-Pb dating reveals that volcanic rocks of the Beisi and Banba formations formed between 248.8±1.6 and 246.5±1.3 Ma,coeval with peraluminous granites of the Qinzhou Bay Granitic *** studied rhyolites and dacites are characterized by high SiO_(2),K_(2)O,and Al_(2)O_(3),and low MgO,CaO,and P_(2)O_(5) contents and are classified as high-K calc-alkaline S-type rocks,with A/CNK=*** volcanic rocks are depleted in high field strength elements,e.g.,Nb,Ta,Ti,and P,and enriched in large ion lithophile elements,e.g.,Rb,K,Sr,and *** the analyzed volcanic rocks have extremely enriched zircon Hf isotopic compositions(ε_(Hf)(t)=-29.1 to-6.9),source discrimination indicators and high calculated Ti-in-zircon temperatures(798-835℃)reveal that magma derived from enriched lithospheric mantle not only provided a heat source for anatectic melting of the metasedimentary protoliths but was also an endmember component of the S-type silicic *** studied early Triassic volcanics are inferred to have formed immediately before closure of the Paleo-Tethys Ocean in this region,as the associated subduction would have generated an extensional setting in which the mantle-derived upwelling and volcanic activity occurred.

关键词： geochemistry silicic volcanic rocks mantle contribution Olenekian-Anisian Paleo-Tethys oceanic plate subduction

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： liu lei liu Jian-cheng LI Xin XU Li-xin ZHANG Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Associative Tasks Computing Offloading Scheme in Internet of Medical Things with Deep Reinforcement Learning

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China Communications 2024年第4期21卷 38-52页

作者： Jiang Fan Qin Junwei liu lei Tian Hui School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The Internet of Medical Things(Io MT) is regarded as a critical technology for intelligent healthcare in the foreseeable 6G era. Nevertheless, due to the limited computing power capability of edge devices and task-related coupling relationships, Io MT faces unprecedented challenges. Considering the associative connections among tasks, this paper proposes a computing offloading policy for multiple-user devices(UDs) considering device-to-device(D2D) communication and a multi-access edge computing(MEC)technique under the scenario of Io MT. Specifically,to minimize the total delay and energy consumption concerning the requirement of Io MT, we first analyze and model the detailed local execution, MEC execution, D2D execution, and associated tasks offloading exchange model. Consequently, the associated tasks’ offloading scheme of multi-UDs is formulated as a mixed-integer nonconvex optimization problem. Considering the advantages of deep reinforcement learning(DRL) in processing tasks related to coupling relationships, a Double DQN based associative tasks computing offloading(DDATO) algorithm is then proposed to obtain the optimal solution, which can make the best offloading decision under the condition that tasks of UDs are associative. Furthermore, to reduce the complexity of the DDATO algorithm, the cacheaided procedure is intentionally introduced before the data training process. This avoids redundant offloading and computing procedures concerning tasks that previously have already been cached by other UDs. In addition, we use a dynamic ε-greedy strategy in the action selection section of the algorithm, thus preventing the algorithm from falling into a locally optimal solution. Simulation results demonstrate that compared with other existing methods for associative task models concerning different structures in the Io MT network, the proposed algorithm can lower the total cost more effectively and efficiently while also providing a tradeoff between delay and energy co

关键词： associative tasks cache-aided procedure double deep Q-network Internet of Medical Things(IoMT) multi-access edge computing(MEC)

Effects of strengthening prospective nursing practice on sleep quality,anxiety,and depression of awake patients in intensive care unit

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World Journal of Psychiatry 2024年第5期14卷 735-741页

作者： Fei Lin lei liu Department of Intensive Care Unit Dushu Lake Hospital Affiliated to Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

BACKGROUND The intensive care unit(ICU)is a specialized hospital *** patients in the ICU frequently encounter adverse psychological states,such as anxiety and fear,often accompanied by poor sleep *** situation has garnered significant attention within the medical *** To investigate the impact of prospective nursing intervention strategies on the sleep quality and negative emotional state of conscious ICU *** One hundred and twenty ICU awake patients admitted to our hospital were selected and randomly divided into control(n=60)and observation(n=60)*** in the control group were cared for using the conventional nursing model,while patients in the observation group were cared for using the prospective nursing *** improvement was assessed using the International Standardized Sleep Efficiency Formula and Pittsburgh Sleep Quality Index(PSQI).The PSQI,Generalized Anxiety Disorder 7-item(GAD-7)scale,Self-Depression Scale(SDS),and satisfaction before and after treatment were used to assess the negative emotional states of patients under the two care *** Patient satisfaction in the observation group was significantly higher than in the control *** GAD-7 and SDS scores in the observation group were significantly lower than those in the control group,and the total effective rate of sleep improvement in the observation group was significantly higher than in the control *** treatment,the PSQI scores of the two groups significantly decreased(P<0.05).The decrease in the observation group was more significan than that in the control group,and the difference between the two groups was statistically *** Prospective nursing interventions can improve sleep quality and psychological levels and significantly affect conscious patients in the ICU,which is worthy of clinical application.

关键词： Prospective nursing Intensive care unit Sobriety Mental health sleep quality Anxiety and depression

Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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Journal of Energy Chemistry 2024年第4期91卷 27-35页

作者： Yonghai Feng Min Yu Minjia Meng lei liu Dewei Rao Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C *** the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to *** carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction ***,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→***,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling.

关键词： Selective oxidation Copper and nitrogen doped carbon 1,2-Propanediol Ultrasmall Cu nanoparticles Lactic acid

IoV environment exploring coordination:A federated learning approach

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Digital Communications and Networks 2024年第1期10卷 135-141页

作者： Tong Ding lei liu Yi Zhu Lizhen Cui Zhongmin Yan School of Software Shandong UniversityJinan250101China

Exploring open fields with coordinated unmanned vehicles is popular in academia and *** of the most impressive applicable approaches is the Internet of Vehicles(lov).The IoV connects vehicles,road infrastructures and communication facilities to provide solutions for exploration ***,the coordination of acquiring information from multi-vehicles may risk data *** this end,sharing high-quality experiences instead of raw data has become an urgent *** paper employs a Deep Reinforcement Learning(DRL)method to enable IoVs to generate training data with prioritized experience and states,which can support the IoV to explore the environment more ***,a Federated Learning(FL)experience sharing model is established to guarantee the vehicles'*** numerical results show that the proposed method presents a better successful sharing rate and a more stable convergence within the comparison of fundamental *** experiments also suggest that the proposed method could support agents without full information to achieve the tasks.

关键词： Internet of vehicle Deep reinforcement learning Federated learning Data privacy

Injectable hydrogel-based drug delivery systems for enhancing the efficacy of radiation therapy:A review of recent advances

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Chinese Chemical Letters 2024年第8期35卷 128-137页

作者： Ningyue Xu Jun Wang lei liu Changyang Gong Division of Head&Neck Tumor Multimodality Treatment Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

Radiotherapy(RT)is a crucial treatment for cancer;however,its effectiveness is limited by adverse effects on normal tissues,radioresistance,and tumor *** overcome these challenges,hydrogels have been employed for delivery of radiosensitizers and other therapeutic *** review summarizes recent advancements in the application of hydrogel-based local drug delivery systems for improving the therapeutic efficacy of RT in cancer ***,we introduce the classification and properties of ***,we detail hydrogel-based platforms designed to enhance both external beam radiation therapy and *** also discuss hydrogels used in combination therapy involving RT and ***,we highlight the challenges that hydrogels face in *** surveying the latest developments in hydrogel applications for RT,this review aims to provide insights into the development of more effective and targeted cancer therapies.

关键词： Radiotherapy Drug delivery systems Hydrogel Radiation sensitization Combination therapy