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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains, China

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Journal of Forestry Research 2024年第3期 88-99页

作者： Jinkuan Li Jianfeng Peng Xiaoxu Wei Meng Peng Xuan Li Yameng Liu Jiaxin Li college of Geography and Environmental science Henan University Key Laboratory of earth System Observation and Simulation of Henan Province

Global warming will affect growth strategies and how trees will adapt. To compare the response of tree radial growth to climate warming in different slope directions, samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains. Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–July. The difference of the climate response to slopes was small but not negligible. Radial growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures, while that of the LBL02 site was affected by maximum temperatures. With regards to moisture, radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July, while on the western slope, it was affected by the relative humidity in the previous June–August, the current May–July and the precipitation in the current May–July. With the change in climate, the effects of the main limiting factors on growth on different slopes were visible to a certain extent, but the differences in response of trees on different slopes gradually decreased, which might be caused by factors such as different slope directions and the change in diurnal temperature range. These results may provide information for forest protection and ecological construction in this region, and a scientific reference for future climate reconstruction.

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Scenarios analysis and performance assessment of blockchain integrated in 6G scenarios

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science China(Information sciences) 2024年第7期67卷 5-26页

作者： Bo LI Guanjie CHENG Honghao GAO Xueqiang YAN Shuiguang DENG college of Computer science and Technology Zhejiang University college of Computer science and Technology Shanghai University 2012 Lab Huawei Technologies Co. Ltd.

Emerging applications such as smart city infrastructures and virtual reality landscapes are setting rigorous benchmarks for 6G mobile networks, requiring elevated levels of confidentiality, integrity, nonrepudiation, authentication, and stringent access controls. Blockchain technology is heralded as a transformative enabler for meeting 6G standards, owing to its intrinsic attributes. However, a gap exists in the holistic investigation of blockchain's applicability in 6G realms, particularly addressing the “whether”, “when”, and“how” of its deployment. Present research trails in developing robust methodologies to gauge blockchain's efficacy within 6G use cases. Addressing this, our study introduces a novel confluence of blockchain with 6G networks, where data resides in distributed Hash tables(DHTs) while their hashes are secured in distributed ledger technology(DLT), harnessing blockchain's core strengths-immutability, traceability, and fortified security. We delineate seven specific 6G use cases poised for enhancement through blockchain integration,and scrutinize the rationale, nature, and timing of this convergence. Furthermore, we devise a comprehensive methodology for assessing blockchain's performance metrics and scalability in 6G environments. Our extensive experimental analyses evaluate the synergistic performance of this integration, revealing that the Quorum blockchain satisfactorily supports 80% of 6G scenarios. The findings suggest that, with appropriate configurations, consortium blockchains are well-equipped to fulfill the demanding performance and scalability requisites of 6G networks.

关键词： blockchain distributed ledger technology (DLT) 6G performance assessment 6G scenarios analysis transaction arrival rate

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Pyridine-regulated Sb@InSbS3 ultrafine nanoplates as high-capacity and long-cycle anodes for sodium-ion batteries

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Rare Metals 2024年第5期43卷 2080-2092页

作者： Jia-Ying Ren Xiang-Lin Yu Chang-Miao Chen Xin-Yu Hu Ting Yang Ming Zhang college of Materials science and Engineering and college of science Central South University of Forestry and Technology college of Semiconductors (college of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan University

Sb-based materials exhibit considerable potential for sodium-ion storage owing to their high theoretica capacities.However,the bulk properties of Sb-based materials always result in poor cycling and rate performances.To overcome these issues,pyridine-regulated Sb@InSbS3ultrafine nanoplates loaded on reduced graphene oxides （Sb@InSbS3@rGO） were designed and synthesized.During the synthesis process,pyridine was initially adopted to coordinate with In3+,and uniformly dispersed In2S3ultrafine nanoplates on reduced graphene oxide were generated after sulfidation.Next,partial In3+was exchanged with Sb3+,and Sb@InSbS3@rGO was obtained by using the subsequent annealing method.The unique structure of Sb@InSbS3@rGO effectively shortened the transfer path of sodium ions and electrons and provided a high pseudocapacitance.As the anode in sodium-ion batteries,the Sb@InSbS3@rGO electrode demonstrated a significantly higher reversible capacity better stability (445 m Ah·g-1at 0.1 A·g-1after 200 cycles and 212 mAh·g-1at 2 A·g-1after 1200 cycles),and superior rate (210 mAh·g-1at 6.4 A·g-1) than the electrode without pyridine (355 mAh·g-1at 0.1 A·g-1after 55 cycles and 109 mAh·g-1at 2 A·g-1after 770 cycles)Furthermore,full cells were assembled by using the Sb@InSbS3@rGO as anode and Na3V2（PO4）3as cathode which demonstrated good cycling and rate performances and exhibited promising application prospects.These results indicate that adjusting the microstructure of electrode materials through coordination balance is A·good strategy for obtaining high-capacity,high-rate,and longcycle sodium storage performances.

关键词： Sodium-ion battery Sb-based anode material Pyridine coordination Reduced size nanostructure Half/full cell

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Boosting spring runoff into the sea by reservoir regulation and its potential for estuarine fishery recovery

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science China earth sciences 2024年第5期67卷 1591-1603页

作者： Xiao WU Houjie WANG Yongyong FAN Naishuang BI Chiyuan MIAO Jingping XU Zuosheng YANG college of Marine Geosciences Key Laboratory of Submarine Geosciences and Prospecting Technologyand Frontiers Science Center for Deep Ocean Multispheres and Earth SystemOcean University of ChinaQingdao 266100China Laoshan National Laboratory Qingdao 266061China Institute of the Yellow River Estuary and Coast science Dongying 257000China State Key Laboratory of earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Ocean science&Engineering Southern University of Science and TechnologyShenzhen 518055China

With global surge in reservoir construction over the past decades,river systems worldwide have been profoundly fragmented.Consequently,flow manipulation by reservoirs has altered the natural hydrological processes,resulting in extensive modifications of fluvial-marine ecosystems.Mitigating the adverse ecological consequences of reservoirs has become a global concern and has garnered increasing attention.The Yellow River,as one of the most extensively manipulated river systems globally,has experienced substantial changes in the amount and timing of water discharge due to the presence of numerous reservoirs scattered throughout its catchment area.These alterations have caused physicochemical changes in the estuary and subsequent modifications to the estuarine ecosystem.In recent years,the Yellow River Conservancy Committee initiated the release of water through the Xiaolangdi Dam during the major spawning period of fisheries,specifically in the spring,with the aim of improving the estuarine ecological environment.From 2011 to 2020,a total of 84.05 km^(3)of water was discharged from the Xiaolangdi Reservoir during spring seasons,of which 40%(33.16 km^(3))constituted water impounded within the reservoir during preceding months.Correspondingly,the spring water discharge from the Yellow River to the sea increased significantly from 1.50 km^(3)/yr to 3.46 km^(3)/yr in the past decade,leading to a decrease in estuarine salinity by 1.6 PSU.The estuarine fishery resources,such as fish eggs in the Yellow River estuary,have demonstrated evident improvement.The reservoir regulation in the Yellow River,which has successfully enhanced spring water discharge and subsequently restored estuarine fishery resources,presents an effective attempt for mitigating the adverse ecological effects associated with reservoirs.

关键词： Reservoir regulation Water release Spring runoff Estuarine ecosystem Yellow River

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Inertinite in coal and its geoenvironmental significance:Insights from AI and big data analysis

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science China earth sciences 2024年第6期67卷 1779-1801页

作者： Longyi SHAO Jiamin ZHOU Timothy PJONES Fanghui HUA Xiaotao XU Zhiming YAN Haihai HOU Dongdong WANG Jing LU State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources and college of Geoscience and Surveying Engineering China University of Miningand Technology(Beijing)Beijing 100083China School of earth and Environmental sciences Cardiff UniversityCardiff CF103YEWalesEngland General Prospecting Institute of China National Administration of Coal Geology Beijing 100039China Institute of Architectural Engineering Weifang UniversityWeifang 261061China college of Mining Liaoning Technical UniversityFuxin 123000China college of earth science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Inertinite,as an important and abundant maceral group in coal,is critical for the study of palaeowildfires and their roles in the earth’s ecosystems.Recently,there has been a significant amount of research on the relationship between palaeowildfire,palaeoclimate change and palaeovegetation evolution based on inertinite data.The reflectance of fusinite and semifusinite has been used to estimate the combustion temperature and type of palaeowildfires,and then to evaluate the combustion characteristics of different types of palaeowildfires.The relative abundance of inertinite can be used to estimate the atmospheric oxygen contents.The rapid development of artificial intelligence(AI)and online tools to search scientific databases has presented an opportunity for us to find,collect,arrange,and analyse data from the earliest to latest publications on inertinite.The data extraction tool Deep Shovel is used to collect and analyse global inertinite data from the Silurian to the Neogene.The software programs such as Gplates,ArcGIS pro and Tableau are then applied to model the relative abundance of inertinite over geological time,which can be correlated with other parameters such as atmospheric oxygen contents,plant evolution and palaeoclimate changes.The distribution of inertinite in coals varied over different geological periods,being typified by the“high inertinite content-high atmospheric oxygen level”period in the Permian and the“low inertinite content-low atmospheric oxygen level”period in the Cenozoic.This study has proposed a possible model of the positive and negative feedbacks between inertinite characteristics and palaeoenvironmental factors,and has revealed the exceptional role of inertinite in palaeoenvironmental studies.Future research on inertinite will be focused on the integrated study of organic petrology and organic geochemistry of inertinite,the big data-driven research on the temporal and spatial distribution of the global inertinite,the exploration of the functions of palaeowildfires in the earth system

关键词： Inertinite Palaeowildfires Atmospheric oxygen Palaeoclimates Palaeoecosystems

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Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong Zhi-Cheng Zeng Guang-Zong Min Zhao-Hui Meng Guo-Qing Meng Xiao-Xiao Guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource shortage.Here,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus evaporator.Based on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one step.Meanwhile,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk fibroin.Our evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)irradiation.Additionally,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

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Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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science China Technological sciences 2024年第6期67卷 1923-1932页

作者： ZHAO Tao SHI Yan LU Kun XI Xiang WU XueZhong XIAO DingBang college of Intelligence science and Engineering National University of Defense Technology

The quality factor(Q factor) is a crucial performance parameter for resonators. In this paper, a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is proposed. This method is based on femtosecond laser-assisted chemical etching. First, the optimal energy range of femtosecond laser modification is obtained through mechanism analysis. Second, the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power, processing speed, and processing spacing. The results demonstrate why edge breakage in rounded corners is easy under different parameters. Finally, according to these conclusions, the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 million. In addition, subsurface damage is rare throughout the fabrication process, and the surface roughness of the released cross section reaches the nanometer level. The improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift, constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

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Dynamic modeling of cavitation bubble clusters:Effects of evaporation,condensation,and bubble-bubble interaction

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Chinese Physics B 2024年第4期33卷 527-535页

作者：许龙姚昕锐沈阳 college of science China Jiliang UniversityHangzhou 310018China

We present a dynamic model of cavitation bubbles in a cluster,in which the effects of evaporation,condensation,and bubble-bubble interactions are taken into consideration.Under different ultrasound conditions,we examine how the dynamics of cavitation bubbles are affected by several factors,such as the locations of the bubbles,the ambient radius,and the number of bubbles.Herein the variations of bubble radius,energy,temperature,pressure,and the quantity of vapor molecules are analyzed.Our findings reveal that bubble-bubble interactions can restrict the expansion of bubbles,reduce the exchange of energy among vapor molecules,and diminish the maximum internal temperature and pressure when bursting.The ambient radius of bubbles can influence the intensities of their oscillations,with clusters comprised of smaller bubbles creating optimal conditions for generating high-temperature and high-pressure regions.Moreover,an increase in the number of bubbles can further inhibit cavitation activities.The frequency,pressure and waveform of the driving wave can also exert a significant influence on cavitation activities,with rectangular waves enhancing and triangular waves weakening the cavitation of bubbles in the cluster.These results provide a theoretical basis for understanding the dynamics of cavitation bubbles in a bubble cluster,and the factors that affect their behaviors.

关键词： bubble dynamics bubble-bubble interaction mass exchange ultrasound waveform

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Granger causal representation learning for groups of time series

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science China(Information sciences) 2024年第5期67卷 56-68页

作者： Ruichu CAI Yunjin WU Xiaokai HUANG Wei CHEN Tom Z.J.FU Zhifeng HAO School of Computer science Guangdong University of Technology Peng Cheng Laboratory college of science Shantou University

Discovering causality from multivariate time series is an important but challenging problem.Most existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimization problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis

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miR‑423 sponged by lncRNA NORHA inhibits granulosa cell apoptosis

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Journal of Animal science and Biotechnology 2024年第2期15卷 632-644页

作者： Yuqi Li Zhuofan Zhang Siqi Wang Xing Du Qifa Li college of Animal science and Technology Nanjing Agricultural UniversityNanjing 210095China

Background Atresia and degeneration,a follicular developmental fate that reduces female fertility and is triggered by granulosa cell(GC)apoptosis,have been induced by dozens of miRNAs.Here,we report a miRNA,miR-423,that inhibits the initiation of follicular atresia(FA),and early apoptosis of GCs.Results We showed that miR-423 was down-regulated during sow FA,and its levels in follicles were negatively correlated with the GC density and the P4/E2 ratio in the follicular fluid in vivo.The in vitro gain-of-function experiments revealed that miR-423 suppresses cell apoptosis,especially early apoptosis in GCs.Mechanically speaking,the miR-423 targets and interacts with the 3’-UTR of the porcine SMAD7 gene,which encodes an apoptosis-inducing factor in GCs,and represses its expression and pro-apoptotic function.Interestingly,FA and the GC apoptosis-related lncRNA NORHA was demonstrated as a ceRNA of miR-423.Additionally,we showed that a single base deletion/insertion in the miR-423 promoter is significantly associated with the number of stillbirths(NSB)trait of sows.Conclusion These results demonstrate that miR-423 is a small molecule for inhibiting FA initiation and GC early apoptosis,suggesting that treating with miR-423 may be a novel approach for inhibiting FA initiation and improving female fertility.

关键词： Granulosa cell apoptosis miR-423 NORHA SMAD7 Sow fertility traits

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