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Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： Longfei Chen zhibin He Wenzhi Zhao Xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan gao Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China State Forestry Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810000People's Republic of China College of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental changes.However,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern China.A trench-ing method was used to explore the long-term impacts of thinning on R,Rn and Ra.Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning intensity.Thinning significantly decreased winter R,because of the reduction in Rn but had no significant effect on Ra.The temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to Rn and R_(a) dynamics.Thinning increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial activity.Our results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term thinning.Therefore,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) emissions.The increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity

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Insights into the role of RNA m6 A modification in the metabolic process and related diseases

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Genes & Diseases 2024年第4期11卷 270-295页

作者： Haiming Hu zhibin Li Xia Xie Qiushi Liao Yiyang Hu Chunli Gong Nannan gao Huan Yang Yufeng Xiao Yang Chen Department of Gastroenterology Xinqiao HospitalArmy Medical UniversityChongqing 400037China

According to the latest consensus,many traditional diseases are considered meta-bolic diseases,such as cancer,type 2 diabetes,obesity,and cardiovascular disease.Currently,metabolic diseases are increasingly prevalent because of the ever-improving living standards and have become the leading threat to human health.Multiple therapy methods have been applied to treat these diseases,which improves the quality of life of many patients,but the overall effect is still unsatisfactory.Therefore,intensive research on the metabolic process and the pathogenesis of metabolic diseases is imperative.N6-methyladenosine(m°A)is an important modification of eukaryotic RNAs.It is a critical regulator of gene expression that is involved in different cellular functions and physiological processes.Many studies have indi-cated that m6A modification regulates the development of many metabolic processes and metabolic diseases.In this review,we summarized recent studies on the role of m6A modifica-tion in different metabolic processes and metabolic diseases.Additionally,we highlighted the potential m6A-targeted therapy for metabolic diseases,expecting to facilitate m6A-targeted strategies in the treatment of metabolic diseases.

关键词： Cancer m6A-targeted therapy Metabolic disease Metabolism N6-methyladenosine

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Loss of Tet hydroxymethylase activity causes mouse embryonic stem cell differentiation bias and developmental defects

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Science China Life Sciences 2024年

作者： Mengting Wang Liping Wang Yanxin Huang zhibin Qiao Shanru Yi Weina Zhang Jing Wang Guang Yang Xinyu Cui Xiaochen Kou Yanhong Zhao Hong Wang Cizhong Jiang Shaorong gao Jiayu Chen Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital Shanghai Key Laboratory of Signaling and Disease Research School of Life Sciences and Technology Tongji University Frontier Science Center for Stem Cell Research Tongji University Shanghai Tenth People's Hospital School of Medicine Tongji University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education Orthopaedic Department of Tongji Hospital Tongji University Shanghai Institute of Stem Cell Research and Clinical Translation

The TET family is well known for active DNA demethylation and plays important roles in regulating transcription, the epigenome and development. Nevertheless, previous studies using knockdown（KD） or knockout（KO） models to investigate the function of TET have faced challenges in distinguishing its enzymatic and nonenzymatic roles, as well as compensatory effects among TET family members, which has made the understanding of the enzymatic role of TET not accurate enough. To solve this problem, we successfully generated mice catalytically inactive for specific Tet members(Tetm/m). We observed that, compared with the reported KO mice, mutant mice exhibited distinct developmental defects, including growth retardation, sex imbalance, infertility, and perinatal lethality. Notably, Tetm/mmouse embryonic stem cells（mESCs） were successfully established but entered an impaired developmental program, demonstrating extended pluripotency and defects in ectodermal differentiation caused by abnormal DNA methylation. Intriguingly, Tet3, traditionally considered less critical for m ESCs due to its lower expression level, had a significant impact on the global hydroxymethylation, gene expression, and differentiation potential of mESCs. Notably, there were common regulatory regions between Tet1 and Tet3 in pluripotency regulation. In summary, our study provides a more accurate reference for the functional mechanism of Tet hydroxymethylase activity in mouse development and ESC pluripotency regulation.

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以现代化产业体系建设赋能城乡融合发展:逻辑、堵点与进路

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行政管理改革 2024年第1期 45-53页

作者：贺灿飞高原李志斌北京大学城市与环境学院北京林业大学园林学院城乡规划系中共中央党校(国家行政学院)经济学教研部

作为现代化国家的重要物质技术基础,现代化产业体系建设能够在推动城乡融合发展中发挥积极作用。在理论逻辑上,现代化产业体系建设通过加速传统农业转型升级、引领城乡产业融合发展、畅通城乡要素双向流动、推动实现农村现代化等路径赋... 详细信息

作为现代化国家的重要物质技术基础,现代化产业体系建设能够在推动城乡融合发展中发挥积极作用。在理论逻辑上,现代化产业体系建设通过加速传统农业转型升级、引领城乡产业融合发展、畅通城乡要素双向流动、推动实现农村现代化等路径赋能城乡融合发展。针对要素双向流动受阻、乡村空间利用低效、现代农业发展困难、县域支撑不足等现实堵点,应当以破除城乡要素流动的体制障碍、推动现代化乡村空间治理体系建设、加大现代农业发展的要素投入保障、强化现代化产业体系建设县域支撑等为实践进路,推动现代化产业体系建设更好赋能城乡产业融合发展。

关键词：现代化产业体系城乡融合发展中国式现代化

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Marine Mobile Wireless Channel Modeling Based on Improved Spatial Partitioning Ray Tracing

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China Communications 2020年第3期17卷 1-11页

作者： zhibin gao Bang Liu Zhipeng Cheng Canbin Chen Lianfen Huang Department of Communication Engineering Xiamen UniversityXiamen 361005China China Contribution Bank Fintech Xiamen 361005China

In 5G era,it is expected to achieve wireless network coverage including offshore areas.Modeling of marine wireless channels is the basis of constructing a marine communication system.In this paper,a communication scene between an unmanned aerial vehicle(UAV)and a boat is simulated to study the marine wireless channel.Firstly,an improved spatial partitioning ray tracing algorithm is proposed to track the propagation path of electromagnetic waves at sea surface.Secondly,a mobile channel is simulated and modeled based on the track results.Finally,a loss measurement is carried out in the coastal waters based on the simple wireless channel loss measuring platform,and a path loss propagation model is built.Then we compare the actual measurement data with the simulation results and find that the two are have good consistency,which further verifies the reliability of the simulation.

关键词： marine wireless channel ray tracing channel modeling path loss

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基于海表温度遥感资料重构的热带不稳定波特征分析

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厦门大学学报（自然科学版） 2024年第3期63卷 512-525页

作者：高志斌王云涛柴扉上海交通大学海洋学院上海200240 自然资源部第二海洋研究所卫星海洋环境动力学国家重点实验室浙江杭州310012 厦门大学海洋与地球学院福建厦门361102

[目的]研究赤道东太平洋热带不稳定波(tropical instability waves,TIWs)的时空分布特征及其驱动机制.[方法]利用数据插值经验正交函数方法对MODIS卫星2003-2018年赤道东太平洋海表面温度(sea surface temperature,SST)数据进行重构,进... 详细信息

[目的]研究赤道东太平洋热带不稳定波(tropical instability waves,TIWs)的时空分布特征及其驱动机制.[方法]利用数据插值经验正交函数方法对MODIS卫星2003-2018年赤道东太平洋海表面温度(sea surface temperature,SST)数据进行重构,进而提取TIWs的波长和速度,并分析其时空分布特征以及与赤道风场和流场的关系.[结果]研究发现:TIWs在纬向上呈正负相位交替分布,在经向上则表现为双峰结构.季节性方面,TIWs在3-5月强度最弱,而在8-10月强度最强.纬向风场通过影响赤道纬向流场,特别是南赤道流(South Equatorial Current,SEC)的北分支(SEC-N)和北赤道逆流(North Equatorial Countercurrent,NECC)的剪切调控TIWs的生成;经向风场则通过调制“冷舌”边缘的SST梯度影响TIWs的生成.在年际尺度上,TIWs在厄尔尼诺(El Nino)年受到抑制,在拉尼娜(La Nina)年得到加强.纬向风场、纬向流场和TIWs三者的异常均超前于厄尔尼诺-南方涛动(El Nino-Southern Oscillation,ENSO)指数所刻画的赤道东太平洋SST异常,这表明纬向风场影响下的纬向流场剪切同样驱动TIWs的年际变化.NECC上空纬向风异常较弱,而SEC-N上空纬向风异常较强,这使得SEC-N年际变化主导流场剪切的强度,对TIWs的年际特征有重要作用.[结论]这一发现强调了大气风场和海洋动力过程共同驱动TIWs的季节性特征和年际变化.

关键词：赤道东太平洋海表面温度热带不稳定波厄尔尼诺-南方涛动

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基于EWT-KLD的机械密封金刚石涂层磨损声发射降噪

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西南交通大学学报 2024年第1期59卷 177-184页

作者：林志斌高宏力吴昱东谭咏文西南交通大学机械工程学院四川成都610031

为了准确获得机械密封金刚石涂层在磨损过程的声发射信号,在分析机械密封设备的噪声特性基础上,提出了基于经验小波变换(EWT)和相对熵(KLD)的声发射降噪方法;通过对磨损声发射信号进行经验小波变换得到划分其频带的滤波器组,对磨损声发... 详细信息

为了准确获得机械密封金刚石涂层在磨损过程的声发射信号,在分析机械密封设备的噪声特性基础上,提出了基于经验小波变换(EWT)和相对熵(KLD)的声发射降噪方法;通过对磨损声发射信号进行经验小波变换得到划分其频带的滤波器组,对磨损声发射信号和背景噪声发射信号用相同的滤波器组划分频带;计算相应频带2种信号的相对熵,用累计和算法在升序排列的相对熵中找到首个大于3σ的值作为阈值,保留相对熵值大于阈值的频带重构信号,完成降噪.研究结果表明:本文所提的EWT-KLD方法可以有效抑制不同工况、不同磨损状态的声发射信号的噪声,有效改善了磨损声发射信号的信噪比,尤其是微弱磨损信号的信噪比,提高了密封端面磨损声发射检测的精度和灵敏度;通过与传统降噪方法的对比发现,本文方法能够对不同工况下的密封磨损声发射信号降噪表现出更强的适应性和稳定性,对于及时检测早期密封磨损和准确监测磨损累积变化过程具有重要意义.

关键词：机械密封声发射降噪经验小波分解金刚石涂层

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Band degeneracy enhanced thermoelectric performance in layered oxyselenides by first-principles calculations

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npj Computational Materials 2021年第1期7卷 158-170页

作者： Ning Wang Menglu Li Haiyan Xiao zhibin gao Zijiang Liu Xiaotao Zu Sean Li Liang Qiao School of Physics University of Electronic Science and Technology of ChinaChengduChina Department of Physics National University of SingaporeSingaporeRepublic of Singapore Department of Physics PhysicsLanzhou City UniversityLanzhouChina School of Materials University of New South WalesSydneyAustralia

Band degeneracy is effective in optimizing the power factors of thermoelectric(TE)materials by enhancing the Seebeck coefficients.In this study,we demonstrate this effect in model systems of layered oxyselenide family by the density functional theory(DFT)combined with semi-classical Boltzmann transport theory.TE transport performance of layered LaCuOSe and BiCuOSe are fully compared.The results show that due to the larger electrical conductivities caused by longer electron relaxation times,the n-type systems show better TE performance than p-type systems for both LaCuOSe and BiCuOSe.Besides,the conduction band degeneracy of LaCuOSe leads to a larger Seebeck coefficient and a higher optimal carrier concentration than n-type BiCuOSe,and thus a higher power factor.The optimal figure of merit(ZT)value of 1.46 for n-type LaCuOSe is 22%larger than that of 1.2 for n-type BiCuOSe.This study highlights the potential of wide band gap material LaCuOSe for highly efficient TE applications,and demonstrates that inducing band degeneracy by cations substitution is an effective way to enhance the TE performance of layered oxyselenides.

关键词： degeneracy selenide layered

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Structural-functional unit ordering for high-performance electron-correlated materials

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Interdisciplinary Materials 2023年第1期2卷 30-52页

作者： Guyang Peng Lei Hu Wanbo Qu Chenglong Zhang Shurong Li Ziyu Liu Juncheng Liu Shengwu Guo Yu Xiao zhibin gao Zhen Zhang Yang Zhang Haijun Wu Stephen J.Pennycook Jun Sun Xiangdong Ding State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong UniversityXi'anChina Instrumental Analysis Center Xi'an Jiaotong UniversityXi'anChina Department of Materials Science and Engineering University of TennesseeKnoxvilleTennesseeUSA

Electron-correlated materials have been drawing ever-increasing attention due to their fascinating physical behaviors and extensive application scenarios.In this review,a new method for material research and design(R&D),named structural-functional unit ordering(SFU ordering),which is presented,overcomes the shortcomings—for example,the limitation of finite chemical elements and long R&D circle-of conventional strategy and thus provides guidance for the design of these high-performance functional materials on demand.Meanwhile,with the development of material characterization technologies,SFUs of different scales and types can be directly observed,which,moreover,regulate the corresponding orderings.The review,starts with an introduction of the profile for SFU ordering and the synergistic effect between SFUs.Then,studies on several new high-performance electronic-correlated materials,for example,a ferromagnetic semiconductor with local spin,ferromagnetic metals with spin topologies,ferroelectric thin films with polar topologies,piezoelectric thin films with nanopillars enclosed by charged boundaries,thermoelectric materials with local ferromagnetic nanoparticles and topotactic phase transformation with conducting nanofilaments are stated in detail one by one.The vital aspect is the breaking of local symmetry,the construction,the structure,of SFUs and their orderings existing or theoretically existing,together with the enhanced/new performance.All in all,the main comments of the review tend to the remaining challenges,promising design approaches for the SFUs,and their orderings for high-performance functional materials.

关键词： electron-correlated materials ferroelectric piezoelectric structural-functional unit thermoelectric

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煤与污泥共气化过程中矿物转化及结渣特性分析实验设计

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实验技术与管理 2024年第3期41卷 131-140页

作者：路广军高萍萍马志斌山西大学国家环境保护煤炭废弃物资源化高效利用技术重点实验室山西太原030006

该文设计了一个煤与生活污泥共气化过程中矿物转化及结渣特性分析研究实验。该实验涉及煤与污泥混合样品结渣特性、灰熔融特性及共气化过程中矿物转化等方面的研究。以典型无烟煤和生活污泥为原料,利用碱酸比、硅铝比等指数对其结渣特... 详细信息

该文设计了一个煤与生活污泥共气化过程中矿物转化及结渣特性分析研究实验。该实验涉及煤与污泥混合样品结渣特性、灰熔融特性及共气化过程中矿物转化等方面的研究。以典型无烟煤和生活污泥为原料,利用碱酸比、硅铝比等指数对其结渣特性进行了评价,采用X射线衍射仪与傅里叶红外光谱仪对混合样共气化过程中的矿物相进行了表征。实验结果表明,生活污泥掺量超过50%会导致混合样结渣严重;污泥掺量增大使混合样灰熔融温度降低,掺量为20%时降低效果最显著。与氧化气氛相比,弱还原气氛下掺混更少的污泥即可生成较多的钙长石,从而导致熔融温度降低。通过该实验,能够使学生了解研究含碳固体废物共气化特性的基本方法,培养他们在含碳固废资源化高效利用方面的创新能力。

关键词：共气化生活污泥矿物转化结渣特性灰熔融特性

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