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Effects of wind speed,underlying surface,and seed morphological traits on the secondary seed dispersal in the Tengger Desert,China

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Journal of Arid Land 2024年第4期16卷 531-549页

作者： QU Wenjie ZHAO Wenzhi YANG Xinguo wang Lei ZHANG Xue QU Jianjun Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education Ningxia UniversityYinchuan 750021China University of Chinese Academy of Sciences Beijing 100049China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key *** on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its *** results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the *** morphological traits and underlying surface could generally explain the *** the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed *** seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long *** results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed *** index and wind speed were the two significant influencing factors on the burial of *** explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and lo

关键词： seed dispersal seed morphological traits wind speed vegetation regeneration wind tunnel Tengger Desert

High-Precision Doppler Frequency Estimation Based Positioning Using OTFS Modulations by Red and Blue Frequency Shift Discriminator

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China Communications 2024年第2期21卷 17-31页

作者： Shaojing wang Xiaomei Tang Jing Lei Chunjiang Ma Chao Wen Guangfu Sun School of Electronic Science National University of Defense TechnologyChangsha 410073China

Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) *** paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler.

关键词： channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator

RNAirport:a deep neural network-based database characterizing representative gene models inplants

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Journal of Genetics and Genomics 2024年第6期51卷 652-664页

作者： Sitao Zhu Shu Yuan Ruixia Niu Yulu Zhou Zhao wang Guoyong Xu State Key Laboratory of Hybrid Rice Institute for Advanced Studies(IAS)Wuhan UniversityWuhanHubei 430072China Hubei Hongshan Laboratory WuhanHubei 430070China

A 5'-leader,known initially as the 5'-untranslated region,contains multiple isoforms due to alternative splicing(aS)and alternative transcription start site(aTSS).Therefore,a representative 5'-leader is demanded to examine the embedded RNA regulatory elements in controlling translation ***,we develop a ranking algorithm and a deep-learning model to annotate representative 5'-leaders for five plant *** rank the intra-sample and inter-sample frequency of aS-mediated transcript isoforms using the Kruskal-Wallis test-based algorithm and identify the representative aS-5'-*** further assign a representative 5'-end,we train the deep-learning model 5'leaderP to learn aTsS-mediated 5'-end distribution patterns from cap-analysis gene expression *** model accurately predicts the 5'-end,confirmed experimentally in Arabidopsis and *** representative 5'-leader-contained gene models and 5'leaderP can be accessed at RNAirport(http:/***/leader5P/).The Stage 1 annotation of 5'-leader records 5'-leader diversity and will pave the way to Ribo-Seq open-reading frame annotation,identical to the project recently initiated by human GENCODE.

关键词： 5'-leader Transcript isoforms RNA regulatory elements UORF Deep learning Synthetic biology Translational control

Satellite glial cells in sensory ganglia play a wider role in chronic pain via multiple mechanisms

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Neural Regeneration Research 2024年第5期19卷 1056-1063页

作者： Xiaoyun Qiu Yuanzhi Yang Xiaoli Da Yi wang Zhong Chen Cenglin Xu Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina

Satellite glial cells are unique glial cells that surround the cell body of primary sensory *** increasing body of evidence suggests that in the presence of inflammation and nerve damage,a significant number of satellite glial cells become activated,thus triggering a series of functional *** suggests that satellite glial cells are closely related to the occurrence of chronic *** this review,we first summarize the morphological structure,molecular markers,and physiological functions of satellite glial ***,we clarify the multiple key roles of satellite glial cells in chronic pain,including gap junction hemichannel Cx43,membrane channel Pannexin1,K channel subunit 4.1,ATP,purinergic P2 receptors,and a series of additional factors and their receptors,including tumor necrosis factor,glutamate,endothelin,and ***,we propose that future research should focus on the specific sorting of satellite glial cells,and identify genomic differences between physiological and pathological *** review provides an important perspective for clarifying mechanisms underlying the peripheral regulation of chronic pain and will facilitate the formulation of new treatment plans for chronic pain.

关键词： chronic pain primary sensory neurons satellite glial cells sensory ganglia

Drainage of paddy terraces impacts structures and soil properties in the globally important agricultural heritage of Hani Paddy Terraces,China

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International Soil and Water Conservation Research 2024年第1期12卷 64-76页

作者： Ming wang Li Rong Yanbo Li Jiangcheng Huang Yuanmei Jiao Xiaoyan Wei Institute of International Rivers and Eco-Security Kunming650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Kunming650500China Power China Kunming Engineering Corporation Limited Kunming650051China Department of Geography Yunnan Normal UniversityKunming650500China Yunnan Provincial Archives of Surveying and Mapping(Yunnan Provincial Geomatics Centre) Kunming650032China

Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still *** Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields ***,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 *** results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since *** study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy *** findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces.

关键词： Hani paddy terraces Terraces marginalization Terrace structure degradation Soil productivity Water holding capacity

Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery

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Journal of Mountain Science 2024年第3期21卷 805-819页

作者： JIN Lu CHEN Jun CAI Yu KONG Yecheng wang Yongfeng DUAN Zheng School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Engineering and Technology Research Center for Smart City Anhui Jianzhu UniversityHefei 230601China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency *** and passive microwave data are widely used to monitor lake ice changes with high temporal ***,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of *** work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(*** Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to *** exhibit different ice phenology *** Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up ***,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth ***,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different *** to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up *** short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the ***,this data facilitates quantification of the freeze-melt dynamics.

关键词： Lake ice Sentinel-1 SAR Tibetan Plateau Climate change

Optical Space Time Pulse Position Modulation over Exponential Weibull Turbulence Channel

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Chinese Journal of Electronics 2024年第2期33卷 527-535页

作者： Yue ZHANG Huiqin wang Xuemei MA Minghua CAO Qingbin PENG School of Computer and Communication Lanzhou University of Technology School of Foreign Languages Lanzhou University of Technology

An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via Monte Carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.

关键词： Wireless communication Wireless sensor networks Monte Carlo methods Bit error rate Matching pursuit algorithms Adaptive optics Optical modulation

Boosting the Activity and Stability of the Photoreduction of Diluted CO_(2) by Copper Oxide Decorated CeO_(2) Hetero-shells

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Chemical Research in Chinese Universities 2024年第3期40卷 513-520页

作者： XIAO Mingjiao LI Di WEI Yanze HE Yilei wang Zumin YU Ranbo Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science&Technology BejingBeijing 100083P.R.China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing 100190P.R.China

Inspired by the natural photosynthesis systems,the integrated harnessing and conversion of CO_(2) present a promising solution for addressing the ever-rising global atmospheric concentration of CO_(2).Hollow multi-shelled structured(HoMS)photocatalysts,featuring alternating shells and cavities,have recently gained recognition as efficient nano-reactors for capturing CO_(2) molecules and facilitating effective photoreduction within these hierarchical structures,leveraging the preeminent enrichment *** this work,to augment the photocatalytic efficacy of HoMS in CO_(2) treatment,highly dispersed Cu_(x)O nanoparticles(NPs)were incorporated on the CeO2 shells through a polymer-assisted impregnation method to create more active sites and strengthen the interaction between the hetero-shells and CO_(2) *** photoreduction of the CO_(2)-to-CO rate under a diluted CO_(2)(15%,volume fraction)atmosphere is improved by the introduction of Cu_(x)O NPs,with the highest CO yielding rate reaching 120µmol·h^(−1)·g^(−1) without any sacrificial *** comparison experiments and theoretical calculations reveal that the Cu_(x)O NPs promote the adsorption of CO_(2) molecules in HoMS,accelerate the charge transfer efficiency,and stabilize the surface oxygen vacancies(Ovs)during the photoreduction CO_(2) conversion *** hope these easy-to-prepare HoMS nanoreactors can contribute to the effective enrichment and valorization of CO_(2) in industrial exhaust gases.

关键词： Photoreduction CO_(2) Cu_(x)O/CeO_(2)hollow multi-shell structure(HoMS) Hetero-shell

Enhancing Multi-agent Coordination via Dual-channel Consensus

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Machine Intelligence Research 2024年第2期21卷 349-368页

作者： Qingyang Zhang Kaishen wang Jingqing Ruan Yiming Yang Dengpeng Xing Bo Xu Institute of Automation Chinese Academy of SciencesBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Successful coordination in multi-agent systems requires agents to achieve *** works propose methods through information sharing,such as explicit information sharing via communication protocols or exchanging information implicitly via behavior ***,these methods may fail in the absence of communication channels or due to biased *** this work,we propose to develop dual-channel consensus(DuCC)via contrastive representation learning for fully cooperative multi-agent systems,which does not need explicit communication and avoids biased *** comprises two types of consensus:temporally extended consensus within each agent(inner-agent consensus)and mutual consensus across agents(inter-agent consensus).To achieve DuCC,we design two objectives to learn representations of slow environmental features for inner-agent consensus and to realize cognitive consistency as inter-agent *** DuCC is highly general and can be flexibly combined with various MARL *** extensive experiments on StarCraft multi-agent challenge and Google research football demonstrate that our method efficiently reaches consensus and performs superiorly to state-of-the-art MARL algorithms.

关键词： Multi-agent reinforcement learning contrastive representation learning consensus multi-agent cooperation cognitive consistency