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Tree species identity and interaction determine vertical forest structure in young planted forests measured by terrestrial laser scanning

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Forest Ecosystems 2024年第3期11卷 266-275页

作者： Mengxi Wang Lander Baeten Frieke Van Coillie Kim Calders Kris Verheyen Quentin Ponette Haben Blondeel Bart Muys John Armston Hans Verbeeck Q-ForestLab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Forest&Nature Lab Department of EnvironmentFaculty of Bioscience EngineeringGhent UniversityBelgium Earth and Life Institute Université Catholique de Louvain(UCLouvain)Louvain-la-NeuveBelgium department of Earth&Environmental sciences KU LeuvenBelgium department of geographical sciences University of MarylandCollege ParkMDUSA

Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and *** tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree ***,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in *** laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented ***,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest *** plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition *** generated vertical plant profiles from the TLS data and derived six stand structural *** mixed models were used to test the effect of species richness on structural *** a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural *** results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height *** identity on the other hand exhibited a significant impact on vertical forest structure across all *** interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these ***,our results highlighted the importance of considering both species identity an

关键词： TreeDivNet FORBIO Stand structural complexity Terrestrial laser scanning Vertical forest structure Tree diversity Planted forests

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Revealing the role of CCoAOMT1: fine-tuning bHLH transcription factors for optimal anther development

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Science China(Life sciences) 2024年第3期67卷 565-578页

作者： Zesen Lai Jianzheng Wang Ying Fu Menghan Wang Hong Ma Shiqing Peng Fang Chang State Key Laboratory of Genetic engineering Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering and Institute of Biodiversity SciencesInstitute of Plant BiologySchool of Life SciencesFudan UniversityShanghai 200438China School of Tropical Agriculture and Forestry Agriculture-Rural Affairs and Rural RevitalizationHainan UniversityHaikou 570228China Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of AgricultureInstitute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China department of Biology Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPA 16802USA

The tapetum,a crucial innermost layer encompassing male reproductive cells within the anther wall,plays a pivotal role in normal pollen *** transcription factors (TFs) bHLH010/089/091 redundantly facilitate the rapid nuclear accumulation of DYSFUNCTIONAL TAPETUM 1,a gatekeeper TF in the ***,the regulatory mechanisms governing the activity of bHLH010/089/091 remain *** this study,we reveal that caffeoyl coenzyme A O-methyltransferase 1 (CCoAOMT1) is a negative regulator affecting the nuclear localization and function of bHLH010 and bHLH089,probably through their K259 *** findings underscore that CCoAOMT1 promotes the nuclear export and degradation of bHLH010 and ***,elevated CCoAOMT1 expression resulted in defective pollen development,mirroring the phenotype observed in bhlh010 bhlh089 ***,our investigation revealed that the K259A mutation in the bHLH089 protein disrupted its translocation from the nucleus to the cytosol and impeded its degradation induced by ***,transgenic plants with the probHLH089::bHLH089^(K259A)construct failed to rescue proper pollen development or gene expression in bhlh010 bhlh089 ***,these findings emphasize the need to maintain balanced TF homeostasis for male *** firmly establish CCoAOMT1 as a pivotal regulator that is instrumental in achieving equilibrium between the induction of the tapetum transcriptional network and ensuring appropriate anther development.

关键词： anther development nuclear localization bHLH O-methyltransferase transcription factor homeostasis

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AFBNet: A Lightweight Adaptive Feature Fusion Module for Super-Resolution Algorithms

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Computer Modeling in engineering & sciences 2024年第9期140卷 2315-2347页

作者： Lirong Yin Lei Wang Siyu Lu Ruiyang Wang Haitao Ren Ahmed AlSanad Salman A.AlQahtani Zhengtong Yin Xiaolu Li Wenfeng Zheng department of Geography and Anthropology Louisiana State UniversityBaton RougeLA70803USA School of Automation University of Electronic Science and Technology of ChinaChengdu610054China College of Computer and Information sciences King Saud UniversityRiyadh11574Saudi Arabia College of Resource and Environment engineering Guizhou UniversityGuiyang550025China School of geographical sciences Southwest UniversityChongqing400715China

At present,super-resolution algorithms are employed to tackle the challenge of low image resolution,but it is difficult to extract differentiated feature details based on various inputs,resulting in poor generalization *** this situation,this study first analyzes the features of some feature extraction modules of the current super-resolution algorithm and then proposes an adaptive feature fusion block(AFB)for feature *** module mainly comprises dynamic convolution,attention mechanism,and pixel-based gating *** with dynamic convolution with scale information,the network can extract more differentiated feature *** introduction of a channel spatial attention mechanism combined with multi-feature fusion further enables the network to retain more important feature *** convolution and pixel-based gating mechanisms enhance the module’s ***,a comparative experiment of a super-resolution algorithm based on the AFB module is designed to substantiate the efficiency of the AFB *** results revealed that the network combined with the AFB module has stronger generalization ability and expression ability.

关键词： Super-resolution feature extraction dynamic convolution attention mechanism gate control

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

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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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DPAL-BERT:A Faster and Lighter Question Answering Model

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Computer Modeling in engineering & sciences 2024年第10期141卷 771-786页

作者： Lirong Yin Lei Wang Zhuohang Cai Siyu Lu Ruiyang Wang Ahmed AlSanad Salman A.AlQahtani Xiaobing Chen Zhengtong Yin Xiaolu Li Wenfeng Zheng department of Geography and Anthropology Louisiana State UniversityBaton RougeLA 70803USA School of Automation University of Electronic Science and Technology of ChinaChengdu610054China College of Computer and Information sciences King Saud UniversityRiyadh11574Saudi Arabia School of Electrical and Computer engineering Louisiana State UniversityBaton RougeLA 70803USA College of Resources and Environmental engineering Guizhou UniversityGuiyang550025China School of geographical sciences Southwest UniversityChongqing400715China

Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering ***,with the constant evolution of algorithms,data,and computing power,the increasing size and complexity of these models have led to increased training costs and reduced *** study aims to minimize the inference time of such models while maintaining computational *** also proposes a novel Distillation model for PAL-BERT(DPAL-BERT),specifically,employs knowledge distillation,using the PAL-BERT model as the teacher model to train two student models:DPAL-BERT-Bi and *** research enhances the dataset through techniques such as masking,replacement,and n-gram sampling to optimize knowledge *** experimental results showed that the distilled models greatly outperform models trained from *** addition,although the distilled models exhibit a slight decrease in performance compared to PAL-BERT,they significantly reduce inference time to just 0.25%of the *** demonstrates the effectiveness of the proposed approach in balancing model performance and efficiency.

关键词： DPAL-BERT question answering systems knowledge distillation model compression BERT Bi-directional long short-term memory(BiLSTM) knowledge information transfer PAL-BERT training efficiency natural language processing

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Impact crater recognition methods:A review

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Science China Earth sciences 2024年第6期67卷 1719-1742页

作者： Dong CHEN Fan HU Liqiang ZHANG Yunzhao WU Jianli DU Jiju PEETHAMBARAN College of Civil engineering Nanjing Forestry UniversityNanjing 210037China department of Geography State Key Laboratory of Remote Sensing ScienceFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China Key Laboratory of Space Object and Debris Observation Chinese Academy of SciencesNanjing 210023China department of Mathematics and Computing Science Saint Mary’s UniversityHalifaxNS B3H 3C3Canada

Impact craters are formed due to the high-speed collisions between small to medium-sized celestial *** is the most significant driving force in the evolution of celestial bodies,and the impact craters provide crucial insights into the formation,evolution,and impact history of celestial *** this paper,we present a detailed review of the characteristics of impact craters,impact crater remote sensing data,recognition algorithms,and applications related to impact *** first provide a detailed description of the geometric texture,illumination,and morphology characteristics observed in remote sensing data of *** we summarize the remote sensing data and cataloging databases for the four terrestrial planets(i.e.,the Moon,Mars,Mercury,and Venus),as well as the impact craters on ***,we study the advancement achieved in the traditional methods,machine learning methods,and deep learning methods applied to the classification,segmentation,and recognition of impact ***,based on the analysis results,we discuss the existing challenges in impact crater recognition and suggest some ***,we explore the implementation of impact crater detection algorithms and provide a forward-looking perspective.

关键词： Terrestrial planets Deep space exploration Impact crater Impact crater recognition Deep learning

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Diet and monensin influence the temporal dynamics of the rumen microbiome in stocker and finishing cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 733-748页

作者： Jianmin Chai Caleb P.Weiss Paul A.Beck Wei Zhao Ying Li Jiangchao Zhao Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding College of Life Science and EngineeringFoshan UniversityFoshanChina Division of Agriculture Department of Animal ScienceUniversity of ArkansasFayettevilleARUSA department of Animal and Food sciences Oklahoma State UniversityStillwaterOKUSA Institute of Feed Research of Chinese Academy of Agricultural sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100193China

Background Stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen *** the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were *** calves were then transported to a feedlot and received similar finishing diets with or without *** microbial samples were collected on d 0,28,85 during the stocker stage(S0,S28 and S85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,Pre-Ba,and Final).The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was *** Higher alpha diversity,including the number of observed bacterial features and the Shannon index,was observed in the stocker phase compared to the finishing *** bacterial amplicon sequence variants(ASVs)differentiating different sampling time points were *** treatments during the stocker stage temporally impact the dynamics of rumen *** example,shared bacteria,including Bacteroidales(ASV19)and Streptococcus infantarius(ASV94),were significantly higher in hay rumen on S28,S85,and F0,while Bacteroidaceae(ASV11)and Limivicinus(ASV15)were more abundant in *** affected rumen microbial composition at a specific *** to feedlot significantly influenced microbiome structure and diversity in hay-fed *** taxa associated with body weight were classified,and core microbiotas interacted with each other during the *** In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding *** at the stocker phase may t

关键词： Beef cattle Diet Feedlot phase Monensin Next-generation sequencing Rumen microbiota Stocker

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Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China

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Journal of Mountain Science 2024年第1期21卷 218-235页

作者： WANG Yumeng DENG Qingchun YANG Haiqing LIU Hui YANG Feng ZHAO Yakai School of geographical sciences China West Normal UniversityNanchong 637009China Sichuan Provincial engineering Laboratory of Monitoring and Control for Soil Erosion in Dry Valleys China West Normal UniversityNanchong 637009China Liangshan Soil Erosion and Ecological Restoration in Dry Valleys Observation and Research Station Xide 616753China

rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical facto

关键词： rural settlements Location entropy geographical detector Spatiotemporal differentiation Influencing factors

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Convolution-Transformer for Image Feature Extraction

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Computer Modeling in engineering & sciences 2024年第10期141卷 87-106页

作者： Lirong Yin Lei Wang Siyu Lu Ruiyang Wang Youshuai Yang Bo Yang Shan Liu Ahmed AlSanad Salman A.AlQahtani Zhengtong Yin Xiaolu Li Xiaobing Chen Wenfeng Zheng department of Geography and Anthropology Louisiana State UniversityBaton RougeLA70803USA School of Automation University of Electronic Science and Technology of ChinaChengdu610054China College of Computer and Information sciences King Saud UniversityRiyadh11574Saudi Arabia College of Resources and Environmental engineering Key Laboratory of Karst Georesources and Environment(Guizhou University)Ministry of EducationGuiyang550025China School of geographical sciences Southwest UniversityChongqing400715China School of Electrical and Computer engineering Louisiana State UniversityBaton RougeLA70803USA

This study addresses the limitations of Transformer models in image feature extraction,particularly their lack of inductive bias for visual *** to Convolutional Neural Networks(CNNs),the Transformers are more sensitive to different hyperparameters of optimizers,which leads to a lack of stability and slow *** tackle these challenges,we propose the Convolution-based Efficient Transformer Image Feature Extraction Network(CEFormer)as an enhancement of the Transformer *** model incorporates E-Attention,depthwise separable convolution,and dilated convolution to introduce crucial inductive biases,such as translation invariance,locality,and scale invariance,into the Transformer ***,we implement a lightweight convolution module to process the input images,resulting in faster convergence and improved *** results in an efficient convolution combined Transformer image feature extraction *** results on the ImageNet1k Top-1 dataset demonstrate that the proposed network achieves better accuracy while maintaining high computational *** achieves up to 85.0%accuracy across various model sizes on image classification,outperforming various baseline *** integrated into the Mask Region-ConvolutionalNeuralNetwork(R-CNN)framework as a backbone network,CEFormer outperforms other models and achieves the highest mean Average Precision(mAP)*** research presents a significant advancement in Transformer-based image feature extraction,balancing performance and computational efficiency.

关键词： Transformer E-Attention depth convolution dilated convolution CEFormer

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Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science China Earth sciences 2024年第5期67卷 1529-1544页

作者： Chuan YUAN Xiaoping YUE Yafeng ZHANG Yu ZHANG Yanting HU Qiang TANG Li GUO Shuai WANG Xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of geographical sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and Mountain River engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community *** advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely *** address this gap,we conducted a systematic review of 1020 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3)^(-)and SO_(4)^(2-))from the Web of Science and Chinese Knowledge Infrastructure *** aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and *** results of this study indicate that stemflow exhibits,on average,2.1times greater ion concentration(6.13 mg L^(-1))compared to *** particular,among the investigated ions,SO_(4)^(2-)(12.45and 6.32 mg L^(-1))for stemflow and throughfall,respectively,and Cl^(-)(9.21 and 4.81 mg L^(-1))exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(13.7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment *** climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid *** the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing *** addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural *** findings emphasize the need for increased attentions to artificial ecosystems,such as urban

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

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