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Elevational distribution of forests and its spatiotemporal dynamics in subtropical China from 2000 to 2019

Science China Earth Sciences 2024年第8期67卷 2563-2582页

作者： Zhencan zheng Liuwen ZHUANG Guofang MIAO han LIU Zhiqiang CHENG Wenyu LI Rong ShanG Peng GONG Jing Ming CHEN Institute of Geography Fujian Normal University Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education) Fujian Normal University School of Geographical Sciences Fujian Normal University National Land Consolidation Center Ministry of Natural Resources Key Laboratory of Land Consolidation and Rehabilitation Ministry of Natural Resources Key Laboratory of Digital Mapping and Land Information Application Ministry of Natural Resources Department of Geography & Planning University of Toronto Department of Geography The University of Hong Kong

The subtropical region of China possesses abundant forest resources and features a mountainous *** the implementation of policies such as natural forest protection,the Grain for Green Project,and other initiatives since the beginning of the 21st century,coupled with climate change,the forest resources in this region have undergone significant changes compared to historical *** addition,forest resources distributing mainly in mountainous areas also implies that these changes may vary significantly with *** explore the spatiotemporal dynamics of forest distribution in subtropical China since 2000,especially the trend of changes with elevation,we analyzed the data from two land cover products focusing on forest cover and forest *** used a hierarchical approach,in which coarse-classification forest cover data with relatively small uncertainties impose constraints on forest type data with larger uncertainties,to achieve a reasonable balance between obtaining more details and reducing data *** first divided the forest cover data into‘unchanged'and‘changed'*** the constraints by the forest cover results,we further analyzed the‘unchanged'and‘changed'forest *** results indicated that,since the implementation of ecological engineering and management policies,54%of the area in the subtropical region had maintained unchanged forest cover attributes over the past 20 years,which implied the good state of ecological *** results also showed that dynamic conversions existed in the long term between forests and lands for essential production needs like *** elevational variations of forest cover suggested that the dominant changes came from the conversion between forests and croplands in low-elevation regions below 700 m,the conversion between forests and shrublands in mid-elevation regions of 700–1500 m,and the conversion between forests and grasslands in high-elevation regions above 2000 *** the regio

关键词： Subtropical China Land cover Forest cover Forest type Elevational distribution

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Light grazing alleviates aeolian erosion–deposition effects on microbial communities in a semi-arid grassland

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Ecological Processes 2024年第2期13卷 148-164页

作者： Mingming Cui Biqi Bao Yipu Wu Nan Hui Mai-He Li Shiqiang Wan Shijie han Feirong Ren Junqiang zheng International Joint Research Laboratory for Global Change Ecology School of Life Sciences Henan University Yellow River Floodplain Ecosystems Research Station School of Life Sciences Henan University School of Agriculture and Biology Shanghai Jiao Tong University Forest Dynam-ics Swiss Federal Institute for Forest Snow and Landscape Research WSL Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of Education School of Geographical Sciences Northeast Normal University School of Life Science Hebei University

Background Soil erosion affects the stability of terrestrial ecosystems and ecosystem services by directly or indirectly impacting the cycling of soil materials and energy and reducing the fertility of grassland soils. However, research on microbial adaptation to grazing and soil erosion is limited, particularly in relation to grassland ecosystem restora-tion. Here, we assess microbial communities subjected to simulated soil erosion and grazing in a semi-arid grassland of Inner Mongolia, *** No significant change was observed in soil variables. However, the structure of the soil microbial commu-nity underwent significant changes as a result of soil erosion and soil erosion plus grazing, leading to a significant increase in the relative abundance of Cyanobacteria(116.80% vs 116.38%). Wind erosion and deposition contributed to an increase in the network complexity of soil bacterial and fungal communities. However, much of this effect was alleviated by grazing. Simultaneously, aeolian processes and grazing regulate soil microbial community assembly, leading to inconsistent patterns of change in bacterial and fungal communities. Under wind erosion and deposi-tion, the relative contribution of deterministic processes(4.44% vs 31.11%) in bacterial communities increased, while the relative contribution of stochastic processes(2.23% vs 20%) in fungal communities reduced. Grazing resulted in a decrease in the relative contribution of deterministic processes(8.89%) in the bacterial community and an increase in the relative contribution of stochastic processes(8.89%) in the fungal *** This study presents a comprehensive investigation of the response of soil microbial communities to aeolian erosion–deposition and grazing in a semi-arid grassland. Our findings indicate that microbial communities in the semi-arid grassland show resistance to external disturbances and that light grazing mitigates the effects of aeo-lian erosion–deposition on microbial co

关键词： Semi-arid grassland Erosion Grazing Soil microbial community network Deposition

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A novel nano-grade organosilicon polymer:Improving airtightness of compressed air energy storage in hard rock formations

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International Journal of Mining Science and Technology 2024年第3期34卷 305-321页

作者： Zhuyan zheng Guibin Wang Chunhe Yang Hongling Ma Liming Yin Youqiang Liao Kai Zhao Zhen Zeng hang Li Yue han Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Geomechanics and Geotechnical Engineering Wuhan 430071China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China PowerChina Huadong Engineering Corporation Limited Hangzhou 310014China

Enhancing cavern sealing is crucial for improving the efficiency of compressed air energy storage(CAES)in hard rock *** study introduced a novel approach using a nano-grade organosilicon polymer(NOSP)as a sealant,coupled with an air seepage evaluation model that incorporates Knudsen ***,the initial coating application methods were outlined,and the advantages of using NOSP compared to other sealing materials,particularly regarding cost and construction techniques,were also examined and *** results indicated a significant reduction in permeability of rock specimens coated with a 7–10μm thick NOSP ***,under a 0.5 MPa pulse pressure,the permeability decreased to less than 1 n D,and under a 4 MPa pulse pressure,it ranged between4.5×10^(-6)–5.5×10^(-6)m D,marking a 75%–80%decrease in granite *** sealing efficacy of NOSP surpasses concrete and is comparable to rubber *** optimal viscosity for application lies between 95 and 105 KU,and the coating thickness should ideally range from 7 to 10μm,applied to substrates with less than 3%*** study provides new insights into air transport and sealing mechanisms at the pore level,proposing NOSP as a cost-effective and simplified solution for CAES applications.

关键词： Compressed air energy storage Lining Permeability Transient pulse method Hard rock cavern Nano-grade organosilicon polymer coating

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Molybdenum Concentration and the Risk of Spontaneous Preterm Birth: A Nested Case-Control Study — Beijing Municipality, China, 2018–2020

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China CDC weekly 2024年第13期6卷 261-266,I0005,I0006页

作者： Junhua Huang Wei zheng Aili Wang Weiling han Junxi Chen hang An Lailai Yan Zhiwen Li Guanghui Li Division of Endocrinology and Metabolism Department of ObstetricsBeijing Obstetrics and Gynecology HospitalCapital Medical University.Beijing Maternal and Child Health Care HospitalBeijingChina Department of Obstetrics and Gynecology Beijing Luhe HospitalCapital Medical UniversityBeijingChina Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive HealthPeking UniversityBeijingChina Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijingChina Department of Laboratorial Science and Technology School of Public HealthPeking UniversityBeijingChina

What is already known about this topic?The level of molybdenum(Mo)in a mother’s urine has been linked to the growth rate of the fetus and the blood pressure levels in *** is added by this report?We evaluated the variations in maternal plasma Mo concentrations throughout pregnancy and their potential association with the risk of spontaneous preterm birth(SPB).What are the implications for public health practice?Future research must determine the Mo levels in pregnant women across various regions in ***,particular attention needs to be given to the potential increase in Mo concentration throughout pregnancy and its possible adverse impacts on the health of both the mother and the fetus.

关键词： mother urine pregnancy

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Cancer-educated neutrophils promote lung cancer progression via PARP-1-ALOX5-mediated MMP-9 expression

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Cancer Biology & Medicine 2024年第2期21卷 175-192页

作者： Lulu han Yuxin Chen Nan Huang Xiaowan Zhou Yanfang Lv Huizhong Li Dafei Chai Junnian zheng Gang Wang Cancer Institute Xuzhou Medical University209 Tongshan RoadXuzhou 221004China Center of Clinical Oncology The Affiliated Hospital of Xuzhou Medical University99 West Huaihai RoadXuzhou 221002China Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy Xuzhou Medical University209 Tongshan RoadXuzhou 221004China Department of Oncology Suzhou Xiangcheng People’s HospitalSuzhou 215131China

Objective:Neutrophils are one of the most predominant infiltrating leukocytes in lung cancer tissues and are associated with lung cancer *** neutrophils promote lung cancer progression,however,has not been ***:Kaplan–Meier plotter online analysis and tissue immunohistochemistry were used to determine the relationship between neutrophils and overall survival in lung cancer *** effect of neutrophils on lung cancer was determined using the Transwell migration assay,a proliferation assay,and a murine tumor *** knockdown was used to determine poly ADPribose polymerase(PARP)-1 function in lung cancer-educated *** blot analysis and gelatin zymography were used to demonstrate the correlation between PARP-1 and matrix metallopeptidase 9(MMP-9).Immunoprecipitation coupled to mass spectrometry(IP/MS)was used to identify the proteins interacting with ***-immunoprecipitation(Co-IP)was used to confirm that PARP-1 interacts with arachidonate 5-lipooxygenase(ALOX5).Neutrophil PARP-1 blockage by AG14361 rescued neutrophil-promoted lung cancer ***:An increased number of infiltrating neutrophils was negatively associated with overall survival in lung cancer patients(Phanism by which PARP-1 mediates lung cancer cell-induced neutrophil activation and PARylates ALOX5 to regulate MMP-9 expression,which exacerbates lung cancer

关键词： Lung cancer neutrophils PARP-1 ALOX5 MMP-9

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Interstitial carbon induces enriched Cu^(δ+) sites in Cu_(2)O nanoparticles to facilitate CO_(2) electroreduction to C_(2+) products

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Nano Research 2024年第8期17卷 7013-7019页

作者： Haoran Wang Rongbo Sun Peigen Liu Haohui Hu Chen Ling Xiao han Yi Shi Xusheng zheng Geng Wu Xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryHefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Sinochem Holdings Co Ltd Xiongan New AreaHebei 071700China National Synchrotron Radiation Laboratory(NSRL) University of Science and Technology of ChinaHefei 230029China

The electrochemical CO_(2) reduction reaction(CO_(2)RR)holds significant promise in advancing carbon *** catalysts for the electrochemical CO_(2)RR to multi-carbon(C_(2+))products(e.g.,C_(2)H_(4))under industrial-level current density is urgently needed and ***,we report the Cu_(2)O nanoparticles doped with interstitial carbon atoms(denoted as C-Cu_(2)O NPs)for the conversion of CO_(2) to C_(2+)*** interstitial carbon promotes the C-Cu_(2)O NPs to possess abundant unsaturated Cu–O bonds,leading to a high-density Cu^(δ+)(0<δ<1)*** obtained C-Cu_(2)O NPs exhibited significant Faradic efficiency(FE)of C_(2+) products approaching 76.9%and a partial current density reaching 615.2 mA·cm^(–2)under an industrial-level current density of 800 mA·cm^(–2).Furthermore,the efficient electrosynthesis of C_(2)H_(4) achieved an FE of 57.4%with a partial current density of 459.2 mA·cm^(–2).In situ electrochemical attenuated total reflection Fourier transform infrared spectroscopy and in situ Raman spectroscopy analyses revealed that C-Cu_(2)O NPs stabilized the intermediate*CO and facilitated C–C coupling,leading to increased selectivity towards C_(2+) products.

关键词： CO_(2) electroreduction C-C coupling interstitial carbon *CO coverage industrial-level current density

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Valence-tailored copper-based nanoparticles for enhanced chemodynamic therapy through prolonged ROS generation and potentiated GSH depletion

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Nano Research 2024年第7期17卷 6342-6352页

作者： Xinyang Li Binbin Ding Jing Li Di han Hao Chen Jia Tan Qi Meng Pan zheng Ping’an Ma Jun Lin State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Chemodynamic therapy(CDT),an inventive approach to cancer treatment,exploits innate chemical processes to trigger cell death through the generation of reactive oxygen species(ROS).While offering advantages over conventional treatments,the optimization of CDT efficacy presents challenges stemming from suboptimal catalytic efficiency and the counteractive ROS scavenging effect of intracellular glutathione(GSH).In this study,we aim to address this dual challenge by delving into the role of copper valence states in *** the unique attributes of copper-based nanoparticles,especially zero-valent copper nanoparticles(CuPd NPs),we aim to enhance the therapeutic potential of *** experiments reveal that zero-valent CuPd NPs outperform divalent copper nanoparticles(Ox-CuPd NPs)by displaying superior catalytic performance and sustaining ROS generation through a dual approach integrating peroxidase-like(POD-like)activity and Cu+***,zero-valent NPs exhibit enhanced GSH depletion compared to their divalent counterparts,thereby intensifying CDT and inducing ferroptosis,ultimately resulting in high-efficiency tumor growth *** findings reveal the impact of valences on CDT,providing novel insights for the optimization and design of CDT agents.

关键词： CuPd nanoparticle ferroptosis chemodynamic therapy valance tailoring tumor therapy

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Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China Chemistry 2024年第7期67卷 2257-2264页

作者： Shi-Quan Song Xiao han Zhong-Zhong Huo Ching-Fai Yip Xian-Fang Hong Meng-Ning Ding You-Xuan zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)***,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these ***,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,*** addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,*** based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,*** importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

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Interlayer exciton dynamics of transition metal dichalcogenide heterostructures under electric fields

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Nano Research 2024年第5期17卷 4555-4572页

作者： Jian Tang Yue zheng Ke Jiang Qi You Zhentian Yin Zihao Xie Henan Li Cheng han Xiaoxian Zhang Yumeng Shi International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Luminescence and Optical Information Ministry of EducationInstitute of Optoelectronic TechnologyBeijing Jiaotong UniversityBeijing 100044China

Stacking single layers of atoms on top of each other provides a fundamental way to achieve novel material systems and engineer their physical properties,which offers opportunities for exploring fundamental physics and realizing next-generation optoelectronic *** the two-dimensional(2D)-stacked systems,transition metal dichalcogenide(TMDC)heterostructures are particularly attractive because they host tightly-bonded interlayer excitons which possess various novel and appealing *** interlayer excitons have drawn significant research attention and hold high potential for the application in unique optoelectronic devices,such as polarization-and wavelength-tunable single photon emitters,valley Hall transistors,and possible high-temperature *** development of these devices requires a comprehensive understanding of the fundamental properties of these interlayer excitons and the impact of electric fields on their *** this review,we summarize the recent advances on the understanding of interlayer exciton dynamics under electric fields in TMDC *** put emphasis on the electrical modulation of interlayer excitons’emission,the valley Hall transport of charge carriers after the separation of interlayer excitons by an electric field,and the correlation physics of interlayer excitons and charges under electrical doping and *** and perspectives are finally discussed for the application of TMDC heterostructures in future optoelectronics.

关键词： interlayer exciton transition metal dichalcogenide(TMDC)heterostructures circular polarization valley Hall effect strong coupling

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Digital Beamforming Demonstration of a Microstrip Antenna Phased Array Feeds(PAF)at 1.25 GHz

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Research in Astronomy and Astrophysics 2024年第10期24卷 76-80页

作者： Peng Wu Mao-zheng Chen Jian Li Kai Wang Liang Cao han Yu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

We introduce the structure of a radio astronomy phased array feeds(PAF)beamforming *** a laboratory environment,we have demonstrated beamforming on a received 1.25 GHz sinusoidal signal and used digital weighting techniques to plot the 2D pattern of the *** radio frequency part of the demonstrator includes a 4×4 linearly polarized microstrip antenna array,all of which is connected in series with a low-noise *** signals from the central 4×2 array elements are injected into a radio frequency system-on-chip digital board,which can receive eight inputs with a bandwidth of 512 *** the principle of undersampling,the beamforming is completed at a frequency of 1.25 GHz for the offline data,and a 2D image of the beam is plotted using beam scanning technology.

关键词： Astronomical Instrumentation Methods and Techniques Astronomical Databases methods:data analysis

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