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Structural variations in oil crops:Types,and roles on domestication and breeding
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作者 Xiaobo Cui Miao Yao +4 位作者 Meili Xie Ming Hu Shengyi Liu Lijiang Liu Chaobo Tong 《Oil Crop Science》 CSCD 2024年第4期240-246,共7页
Structural variations(SVs),a newly discovered genetic variation,have gained increasing recognition for their importance,yet much about them remains unknown.With the completion of whole-genome sequencing projects in oi... Structural variations(SVs),a newly discovered genetic variation,have gained increasing recognition for their importance,yet much about them remains unknown.With the completion of whole-genome sequencing projects in oil crops,more SVs have been identified,revealing their types,genomic distribution,and characteristics.These findings have demonstrated the crucial roles of SVs in regulating gene expression,driving trait innovation,facilitating domestication,making this an opportune time for a systematic review.We summarized the progress of SV-related studies in oil crops,focusing on the types of SVs and their mechanisms of occurrence,the strategies and methods for SV detection,and the SVs identified in oil crops such as rapeseed,soybean,peanut,and sesame.The various types of SVs,such as presence-absence variations(PAVs),copy number variations(CNVs),and homeologous exchanges(HEs),have been shown.Along with their genomic characterization,their roles in crop domestication and breeding,and regulatory impact on gene expression and agronomic traits have also been demonstrated.This review will provide an overview of the SV research process in oil crops,enabling researchers to quickly understand key information and apply this knowledge in future studies and crop breeding. 展开更多
关键词 Structural variations Oil crops Copy number variations Presence or absence variations Homologous exchanges
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A new two-step variational model for multiplicative noise removal with applications to texture images
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作者 ZHANG Long-hui YAO Wen-juan +2 位作者 SHI Sheng-zhu GUO Zhi-chang ZHANG Da-zhi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期486-501,共16页
Multiplicative noise removal problems have attracted much attention in recent years.Unlike additive noise,multiplicative noise destroys almost all information of the original image,especially for texture images.Motiva... Multiplicative noise removal problems have attracted much attention in recent years.Unlike additive noise,multiplicative noise destroys almost all information of the original image,especially for texture images.Motivated by the TV-Stokes model,we propose a new two-step variational model to denoise the texture images corrupted by multiplicative noise with a good geometry explanation in this paper.In the first step,we convert the multiplicative denoising problem into an additive one by the logarithm transform and propagate the isophote directions in the tangential field smoothing.Once the isophote directions are constructed,an image is restored to fit the constructed directions in the second step.The existence and uniqueness of the solution to the variational problems are proved.In these two steps,we use the gradient descent method and construct finite difference schemes to solve the problems.Especially,the augmented Lagrangian method and the fast Fourier transform are adopted to accelerate the calculation.Experimental results show that the proposed model can remove the multiplicative noise efficiently and protect the texture well. 展开更多
关键词 multiplicative noise removal texture images total variation two-step variational method aug-mented Lagrangian method
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Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America
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作者 Zhihui Wang Philip A.Townsend +1 位作者 Eric L.Kruger Anna K.Schweiger 《Forest Ecosystems》 SCIE CSCD 2024年第5期728-742,共15页
Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multi... Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade leaves.We presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North America.We investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait expression.Generally,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific characteristics.Covariation between sun and shade leaf traits,and trait-environment relationships were overall consistent across species.The main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural traits.Taxonomy and canopy position collectively explained most of the foliar trait variation.This study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem functions.Our findings have implications for efficient field sampling,and trait mapping with remote sensing. 展开更多
关键词 Foliar traits Leaf trait variation Trait-environment covariation Shade leaves NEON Leaf spectroscopy
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Insights into genetic diversity and phenotypic variations in domestic geese through comprehensive population and pan-genome analysis 被引量:1
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作者 Guangliang Gao Hongmei Zhang +5 位作者 Jiangping Ni Xianzhi Zhao Keshan Zhang Jian Wang Xiangdong Kong Qigui Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期88-107,共20页
Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and ... Background Domestic goose breeds are descended from either the Swan goose(Anser cygnoides)or the Greylag goose(Anser anser),exhibiting variations in body size,reproductive performance,egg production,feather color,and other phenotypic traits.Constructing a pan-genome facilitates a thorough identification of genetic variations,thereby deepening our comprehension of the molecular mechanisms underlying genetic diversity and phenotypic variability.Results To comprehensively facilitate population genomic and pan-genomic analyses in geese,we embarked on the task of 659 geese whole genome resequencing data and compiling a database of 155 RNA-seq samples.By constructing the pan-genome for geese,we generated non-reference contigs totaling 612 Mb,unveiling a collection of 2,813 novel genes and pinpointing 15,567 core genes,1,324 softcore genes,2,734 shell genes,and 878 cloud genes in goose genomes.Furthermore,we detected an 81.97 Mb genomic region showing signs of genome selection,encompassing the TGFBR2 gene correlated with variations in body weight among geese.Genome-wide association studies utilizing single nucleotide polymorphisms(SNPs)and presence-absence variation revealed significant genomic associations with various goose meat quality,reproductive,and body composition traits.For instance,a gene encoding the SVEP1 protein was linked to carcass oblique length,and a distinct gene-CDS haplotype of the SVEP1 gene exhibited an association with carcass oblique length.Notably,the pan-genome analysis revealed enrichment of variable genes in the“hair follicle maturation”Gene Ontology term,potentially linked to the selection of feather-related traits in geese.A gene presence-absence variation analysis suggested a reduced frequency of genes associated with“regulation of heart contraction”in domesticated geese compared to their wild counterparts.Our study provided novel insights into gene expression features and functions by integrating gene expression patterns across multiple organs and tissues in geese and analyzing population variation.Conclusion This accomplishment originates from the discernment of a multitude of selection signals and candidate genes associated with a wide array of traits,thereby markedly enhancing our understanding of the processes underlying domestication and breeding in geese.Moreover,assembling the pan-genome for geese has yielded a comprehensive apprehension of the goose genome,establishing it as an indispensable asset poised to offer innovative viewpoints and make substantial contributions to future geese breeding initiatives. 展开更多
关键词 Gene-CDS haplotype Goose GWAS PAN-GENOME Presence-absence variation Selection signal
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Associations of genome-wide structural variations with phenotypic differences in cross-bred Eurasian pigs 被引量:1
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作者 Wencheng Zong Jinbu Wang +8 位作者 Runze Zhao Naiqi Niu Yanfang Su Ziping Hu Xin Liu Xinhua Hou Ligang Wang Lixian Wang Longchao Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期68-87,共20页
Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability ... Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds. 展开更多
关键词 Body size GWAS PIG SKELETON Structural variations
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Origin of the presence/absence variation of the LTIA1/LTIA2 mini-ribonucleaseⅢgenes required for low-temperature growth in rice 被引量:1
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作者 Jing Yang Yu Peng +5 位作者 Limin Mi Aiqing Sun Ping Li Yan Wang Yi Zhang Sheng Teng 《The Crop Journal》 SCIE CSCD 2024年第5期1459-1470,共12页
A rice low temperature-induced albino variant was determined by the recessive ltia1 and ltia2 genes.LTIA1 and LTIA2 encode highly conserved mini-ribonucleasesⅢlocated in chloroplasts and expressed in aerial parts of ... A rice low temperature-induced albino variant was determined by the recessive ltia1 and ltia2 genes.LTIA1 and LTIA2 encode highly conserved mini-ribonucleasesⅢlocated in chloroplasts and expressed in aerial parts of the plant.At low temperature,LTIA1 and LTIA2 redundantly affect chlorophyll levels,non-photochemical quenching,photosynthetic quantum yield of PSⅡand seedling growth.LTIA1 and LTIA2 proteins are involved in splicing of atp F and the biogenesis of 16S and 23S rRNA in chloroplasts.Presence/absence variation of LTIA1,the ancestral copy,was found only in japonica but that of LTIA2 in all rice subgroups.Accessions with LTIA2 presence tended to be distributed more remote from the equator compared to those with LTIA2 absence.LTIA2 duplicated from LTIA1 at the early stage of divergence of the AA genome Oryza species but deleted againin O.nivara.In cultivated rice,absence of LTIA2 is derived from O.nivara.LTIA1 absence occurred more recently in japonica. 展开更多
关键词 RICE Low temperature induced albino Mini-RNaseⅢ Presence/Absence variations Evolution
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Spatial Variation in CO_(2) Concentration Improves the Simulated Surface Air Temperature Increase in the Northern Hemisphere 被引量:1
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作者 Jing PENG Li DAN Xiba TANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1614-1628,1676-1685,共25页
The increasing concentration of atmospheric CO_(2) since the Industrial Revolution has affected surface air temperature.However,the impact of the spatial distribution of atmospheric CO_(2) concentration on surface air... The increasing concentration of atmospheric CO_(2) since the Industrial Revolution has affected surface air temperature.However,the impact of the spatial distribution of atmospheric CO_(2) concentration on surface air temperature biases remains highly unclear.By incorporating the spatial distribution of satellite-derived atmospheric CO_(2) concentration in the Beijing Normal University Earth System Model,this study investigated the increase in surface air temperature since the Industrial Revolution in the Northern Hemisphere(NH) under historical conditions from 1976-2005.In comparison with the increase in surface temperature simulated using a uniform distribution of CO_(2),simulation with a nonuniform distribution of CO_(2)produced better agreement with the Climatic Research Unit(CRU) data in the NH under the historical condition relative to the baseline over the period 1901-30.Hemispheric June-July-August(JJA) surface air temperature increased by 1.28℃ ±0.29℃ in simulations with a uniform distribution of CO_(2),by 1.00℃±0.24℃ in simulations with a non-uniform distribution of CO_(2),and by 0.24℃ in the CRU data.The decrease in downward shortwave radiation in the non-uniform CO_(2) simulation was primarily attributable to reduced warming in Eurasia,combined with feedbacks resulting from increased leaf area index(LAI) and latent heat fluxes.These effects were more pronounced in the non-uniform CO_(2)simulation compared to the uniform CO_(2) simulation.Results indicate that consideration of the spatial distribution of CO_(2)concentration can reduce the overestimated increase in surface air temperature simulated by Earth system models. 展开更多
关键词 spatial variations of CO_(2) surface air temperature Earth system model land surface albedo leaf area index
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Variations in evaporation from water surfaces along the margins of the Badain Jaran Desert over nearly 60 years and influencing factors 被引量:1
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作者 Li-juan Wang Zhe Wang +3 位作者 Gao-lei Jiang Zhen-long Nie Jian-mei Shen Sheng-hua Song 《Journal of Groundwater Science and Engineering》 2024年第3期253-263,共11页
Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evapor... Based on meteorological data collected over nearly 60 years(1960-2017)from four national meteorological stations along the margins of the Badain Jaran Desert,this study analyzed the spatiotemporal variations in evaporation from water surfaces and identified the dominant controlling factors.Methods used included linear trend analysis,linear tendency estimation,the departure method,the rank correlation coefficient-based method,and Multiple Linear Regression(MLR).Results indicate notable spatiotemporal differences in evaporation distribution and evolution.Spatially,average annual evaporation exhibited a pronounced altitude effect,decreasing at a rate of about 8.23 mm/m from east to west with increasing altitude.Temporally,annual evaporation showed significant upward trends after 1996 at the northeastern(Guaizi Lake)and western(Dingxin)margins,with rates of 132 mm/10a and 105 mm/10a,respectively.Conversely,along the northwestern(Ejina Banner)and southern(Alxa Right Banner)margins of the desert,an evaporation paradox was observed,with annual evaporation trending downward at rates of 162 mm/10a and 187 mm/10a,respectively,especially after 1987.The dominant factors controlling evaporation varied spatially:Average annual temperature and relative humidity influended the western margin(Dingxin),average annual temperature was the key factor for the northeastern margin(Guaizi Lake),and average wind speed was crucial for the northern(Ejina Banner)and southern(Alxa Right Banner)margins. 展开更多
关键词 Evaporation from water surface Evaporation paradox Dominant controlling factor variation trend
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Small temporal variation in abundance of virioplankton compared to bacterioplankton and phytoplankton in two bays in the northern South China Sea
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作者 Jiandong ZHANG Yineng LI +1 位作者 Lijuan LONG Sijun HUANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1130-1142,共13页
Variations of picoplankton groups were investigated over a one-month period in Daya Bay and Sanya Bay,in the northern South China Sea.The two coastal regions exhibited different variation patterns in physicochemical p... Variations of picoplankton groups were investigated over a one-month period in Daya Bay and Sanya Bay,in the northern South China Sea.The two coastal regions exhibited different variation patterns in physicochemical parameters.Moreover,the diel variations of picoplankton groups were different between the two bays.The abundance of the picoplankton in Sanya Bay displayed a pronounced diel variation,while it was not significant in Daya Bay.In addition,some similar patterns of picoplankton abundance were discovered.In the two bays,virioplankton exhibited the smallest fluctuation range,whereas picocyanobacteria fluctuated most markedly.The fluctuation range of picoplankton groups was larger in spring tide than in neap tide,especially in Sanya Bay.Random forest model analysis demonstrated that the variation of picoplankton groups was attributed to physical and chemical factors in Sanya Bay and Daya Bay,respectively.Therefore,our findings suggest that virioplankton abundance can persist more stably in response to changing environmental conditions compared to bacterioplankton and picophytoplankton. 展开更多
关键词 diel variation ABUNDANCE picoplankton group VIRIOPLANKTON PICOCYANOBACTERIA
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The Variation of Plankton Community Structure in Artificial Reef Area and Adjacent Waters in Haizhou Bay
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作者 GAO Shike SHI Yixi +1 位作者 LU Yanan ZHANG Shuo 《Journal of Ocean University of China》 CAS CSCD 2024年第1期264-276,共13页
Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among MPAs.According to the survey from MPAs dominated by ar... Plankton are an important component of marine protected areas(MPAs),and its communities would require much smaller interpatch distances to ensure connection among MPAs.According to the survey from MPAs dominated by artificial reefs and adjacent waters(estuary area(EA),aquaculture area(AA),artificial reef area(ARA),natural area(NA)and comprehensive effect area(CEA))in Haizhou Bay in spring and autumn,we analyzed phyto-zooplankton composition,abundance and biomass,and correlation with hydrologic variables to gain information about the forces that structure the plankton.The results showed that the dominant zooplankton were copepods(spring,98.9%;autumn,94.2%),while the phytoplankton were mainly composed of Bacillariophyta(spring,61.8%;autumn,95.6%).The RDA results showed that temperature,salinity and depth highly associated with the distribution and composition of plankton species among the habitats than other factors in spring;temperature,Chla and DO had the strongest influence in autumn.The zooplankton in the ARA and AA ecosystems basically contained the same species as those in other habitats,and each habitat also exhibited a relatively unique combination of plankton species.The structures of the EA zooplankton in spring and the EA phytoplankton in both seasons were much different than other habitats,which may have been caused by factors such as currents and tides.We concluded that there exists similarity of the plankton community between artificial reef area and adjacent waters,whereas the EAs may be relatively independent systems.Therefore,these interaction between plankton community should be considered when designing MPA networks,and ocean circulations should be considered more than the environmental factors. 展开更多
关键词 ZOOPLANKTON PHYTOPLANKTON seasonal variation environmental factor artificial reef
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An allelic variation in the promoter of the LRR-RLK gene,qSS6.1,is associated with melon seed size
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作者 Xiaoxue Liang Jiyu Wang +11 位作者 Lei Cao Xuanyu Du Junhao Qiang Wenlong Li Panqiao Wang Juan Hou Xiang Li Wenwen Mao Huayu Zhu Luming Yang Qiong Li Jianbin Hu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3522-3536,共15页
Seed size is an important agronomic trait in melons that directly affects seed germination and subsequent seedling growth.However,the genetic mechanism underlying seed size in melon remains unclear.In the present stud... Seed size is an important agronomic trait in melons that directly affects seed germination and subsequent seedling growth.However,the genetic mechanism underlying seed size in melon remains unclear.In the present study,we employed Bulked-Segregant Analysis sequencing(BSA-seq)to identify a candidate region(~1.35 Mb)on chromosome 6 that corresponds to seed size.This interval was confirmed by QTL mapping of three seed size-related traits from an F2 population across three environments.This mapping region represented nine QTLs that shared an overlapping region on chromosome 6,collectively referred to as qSS6.1.New InDel markers were developed in the qSS6.1 region,narrowing it down to a 68.35 kb interval that contains eight annotated genes.Sequence variation analysis of the eight genes identified a SNP with a C to T transition mutation in the promoter region of MELO3C014002,a leucine-rich repeat receptor-like kinase(LRR-RLK)gene.This mutation affected the promoter activity of the MELO3C014002 gene and was successfully used to differentiate the large-seeded accessions(C-allele)from the small-seeded accessions(T-allele).qRT-PCR revealed differential expression of MELO3C014002 between the two parental lines.Its predicted protein has typical LRR-RLK family domains,and phylogenetic analyses reveled its similarity with the homologs in several plant species.Altogether,these findings suggest MELO3C014002 as the most likely candidate gene involved in melon seed size regulation.Our results will be helpful for better understanding the genetic mechanism regulating seed size in melons and for genetically improving this important trait through molecular breeding pathways. 展开更多
关键词 MELON QTL mapping seed size candidate gene allelic variation
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Temperature is a cryptic factor shaping the geographical pattern of genetic variation in Ceratophyllum demersum across a subtropical freshwater lake
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作者 Yixian Li Xuyao Zhao +2 位作者 Manli Xia Xinzeng Wei Hongwei Hou 《Plant Diversity》 SCIE CAS CSCD 2024年第5期630-639,共10页
Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic stressors.Environmental... Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic stressors.Environmental factors are thought to be important drivers shaping the genetic and epigenetic variation of aquatic plants.However,the links among genetic diversity,epigenetic variation,and environmental variables remain largely unclear,especially for clonal aquatic plants.Here,we performed population genetic and epigenetic analyses in conjunction with habitat discrimination to elucidate the environmental factors driving intraspecies genetic and epigenetic variation in hornwort(Ceratophyllum demersum)in a subtropical lake.Environmental factors were highly correlated with the genetic and epigenetic variation of C.demersum,with temperature being a key driver of the genetic variation.Lower temperature was detected to be correlated with greater genetic and epigenetic variation.Genetic and epigenetic variation were positively driven by water temperature,but were negatively affected by ambient air temperature.These findings indicate that the genetic and epigenetic variation of this clonal aquatic herb is not related to the geographic feature but is instead driven by environmental conditions,and demonstrate the effects of temperature on local genetic and epigenetic variation in aquatic systems. 展开更多
关键词 Genetic diversity Epigenetic variation TEMPERATURE MACROPHYTE Restoration
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Mechanisms for the evolution of cell-to-cell variations and their impacts on fast-charging performance within a lithium-ion battery pack
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作者 Yufang Lu Xiaoru Chen +4 位作者 Xuebing Han Dongxu Guo Yu Wang Xuning Feng Minggao Ouyang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期11-22,共12页
Cell-to-cell variations(CtCV) compromise the electrochemical performance of battery packs, yet the evolutional mechanism and quantitative impacts of CtCV on the pack's fast-charging performance remain unexplored. ... Cell-to-cell variations(CtCV) compromise the electrochemical performance of battery packs, yet the evolutional mechanism and quantitative impacts of CtCV on the pack's fast-charging performance remain unexplored. This knowledge gap is vital for the proliferation of electric vehicles. This study underlies the relationship between CtCV and charging performance by assessing the pack's charge speed, final electric quantity, and temperature consistency. Cell variations and pack status are depicted using 2D parameter diagrams, and an m PnS configured pack model is built upon a decomposed electrode cell model.Variations in three single electric parameters, i.e., capacity(Q), electric quantity(E), and internal resistance(R), and their dual interactions, i.e., E-Q and R-Q, are analyzed carefully. The results indicate that Q variations predominantly affect the final electric quantity of the pack, while R variations impact the charge speed most. With incremental variances in cell parameters, the pack's fast-charging capability first declines linearly and then deteriorates sharply as variations intensify. This research elucidates the correlations between pack charging capabilities and cell variations, providing essential insights for optimizing cell sorting and assembly, battery management design, and charging protocol development for battery packs. 展开更多
关键词 Lithium-ion battery Battery pack Cell-to-cell variation Fast charging Performance evaluation
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Genetic variation and selection of 10-year-old Eucalyptus camaldulensis based on wind damage index and wood properties
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作者 Xiuhua Shang Zhihua Wu +2 位作者 Xiaoming Li Youshuang Wang Peijian Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期173-184,共12页
Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,f... Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,faces significant growth challenges because of typhoon.Therefore,it is vital to investigate the variation of related traits and select superior breeding materials for genetic improvement.Variance,genetic parameter,and correlation analyses were carried out on wind damage indices and eight wood proper-ties in 88 families from 11 provenances of 10-year-old Euca-lyptus camaldulensis.The selection index equation was used for evaluating multiple traits and selecting superior prov-enances and family lines as future breeding material.The results show that all traits were highly significantly differ-ent at provenance and family levels,with the wind damage index having the highest coefficient of genetic variation.The heritability of each trait ranged from 0.48 to 0.87,with the wind damage index,lignin and hemicellulose contents,and microfibril angle having the highest heritabilities.The wind damage index had a positive genetic correlation with wood density,a negative correlation with lignin content,a negative phenotypic correlation and a negative genetic correlation with microfibril angle.Wind damage index and genetic progress in the selection of eight wood traits varied from 7.2%to 614.8%.Three provenances and 12 superior families were selected.The genetic gains of the wind damage index were 10.2%and 33.9%for provenances and families,and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China. 展开更多
关键词 Eucalyptus camaldulensis Wind damage index Wood properties Genetic variation Comprehensive selection
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Environment-driven intraspecific variation shows coordination of functional traits of deciduous oaks among and within different biological levels
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作者 Yutong Lin Yuan Lai +6 位作者 Songbo Tang Jeannine Cavender-Bares Josep Peñuelas Jordi Sardans Jianfeng Liu Lingling Zhang Yuanwen Kuang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期95-109,共15页
Deciduous oaks(Quercus spp.)are distributed from subalpine to tropical regions in the northern hemi-sphere and have important roles as carbon sinks and in climate change mitigation.Determining variations in plant func... Deciduous oaks(Quercus spp.)are distributed from subalpine to tropical regions in the northern hemi-sphere and have important roles as carbon sinks and in climate change mitigation.Determining variations in plant functional traits at multiple biological levels and linking them to environmental variables across geographical ranges is important for forecasting range-shifts of broadly-distrib-uted species under climate change.We sampled leaves of five deciduous Quercus spp.covering approximately 20°of latitude(~21°N-41°N)and 20 longitude(~99°E-119°E)across China and measured 12 plant functional traits at different biological levels.The traits varied distinctively,either within each biological level or among different levels driven by climatic and edaphic variables.Traits at the organ level were significantly correlated with those at the cellular and tissue levels,while traits at the whole-plant level only correlated with those at the tissue level.The Quercus species responded to changing environments by regulating stomatal size,leaf thickness and the palisade mesophyll thickness to leaf thickness ratios with contrasting degree of effect to adjust the whole-plant functioning,i.e.,intrinsic water use efficiency(iWUE),carbon supply and nitrogen availability.The results suggest that these deciduous Quercus spp.will maintain vigour by increasing iWUE when subjected to large temperature changes and insufficient moisture,and by accu-mulating leaf non-structural carbohydrates under drought conditions.The findings provide new insights into the inher-ent variation and trait coordination of widely distributed tree species in the context of climate change. 展开更多
关键词 Climate gradient Intraspecific variation Plant functional traits Deciduous Quercus species Whole-plant function
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Four-to Six-Year Periodic Variation of Arctic Sea-Ice Extent and Its Three Main Driving Factors
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作者 Ping CHEN Jinping ZHAO Xiaoyu WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1999-2010,共12页
Besides the rapid retreating trend of Arctic sea-ice extent(SIE),this study found the most outstanding low-frequency variation of SIE to be a 4-6-year periodic variation.Using a clustering analysis algorithm,the SIE i... Besides the rapid retreating trend of Arctic sea-ice extent(SIE),this study found the most outstanding low-frequency variation of SIE to be a 4-6-year periodic variation.Using a clustering analysis algorithm,the SIE in most ice-covered regions was clustered into two special regions:Region-1 around the Barents Sea and Region-2 around the Canadian Basin,which were located on either side of the Arctic Transpolar Drift.Clear 4-6-year periodic variation in these two regions was identified using a novel method called“running linear fitting algorithm”.The rate of temporal variation of the Arctic SIE was related to three driving factors:the regional air temperature,the sea-ice areal flux across the Arctic Transpolar Drift,and the divergence of sea-ice drift.The 4-6-year periodic variation was found to have always been present since 1979,but the SIE responded to different factors under heavy and light ice conditions divided by the year 2005.The joint contribution of the three factors to SIE variation exceeded 83%and 59%in the two regions,respectively,remarkably reflecting their dynamic mechanism.It is proven that the process of El Niño-Southern Oscillation(ENSO)is closely associated with the three factors,being the fundamental source of the 4-6-year periodic variations of Arctic SIE. 展开更多
关键词 sea-ice extent periodic variation air temperature sea-ice areal flux Arctic Transpolar Drift ice-drift divergence ENSO
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Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO
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作者 Xinyi XING Xianghui FANG +1 位作者 Da PANG Chaopeng JI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期465-477,共13页
El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and de... El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate. 展开更多
关键词 SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation
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Annual variation of adult survival of a south-temperate House Wren population in Argentina
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作者 Gustavo J.Fernandez Mariana E.Carro Paulo E.Llambías 《Avian Research》 SCIE CSCD 2024年第2期229-237,共9页
Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environ... Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the south.Here,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival estimators.We found that the probability of adult survival decreased as the abundance of breeding adults increased.This density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival. 展开更多
关键词 Annual variation CJS DENSITY-DEPENDENCE SURVIVAL Troglodytes aedon bonariae
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Mitogenomic variation in the Black-throated Tit(Aegithalos concinnus):Conserved structure,concerted evolution of duplicate control regions and multiple distinct evolutionary lineages
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作者 Chuanyin Dai Fumin Lei 《Avian Research》 SCIE CSCD 2024年第4期422-430,共9页
The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variati... The mitochondrial genome is a prominent research topic due to its indispensable role in organisms and its application in many research disciplines.However,few studies have investigated intraspecies mitogenomic variation.In this study,69 mitogenomes of the Black-throated Tit(Aegithalos concinnus)were assembled and annotated from a large number of short reads generated using high-throughput sequencing technology.Comparative analyses revealed that mitogenomic characteristics such as length,gene and nucleotide composition,codon usage,and duplicated control regions were relatively conserved despite substantial intraspecies morphological changes.Yet,all the individuals from the subspecies A.c.iredalei had one more nucleotide in the 12S rRNA than the other studied subspecies.Phylogenetic analyses showed five distinct lineages based on the complete mitogenomes and the 13 combined protein-coding genes,whereas only four lineages were observed when using the duplicate control regions.Most interestingly,each lineage had both copies of the control regions of the comprising individuals,indicating that the paralogous control regions were more similar than the orthologous sequences from the distinct lineages.This suggested the control regions had undergone concerted evolution.The Black-throated Tit has complex evolutionary history and needs further investigating the taxonomic status of these lineages,as well as the underlying evolutionary processes.Our findings call for more research on intraspecies mitogenomic variation. 展开更多
关键词 Aegithalos concinnus Concerted evolution Intraspecies variation Lineage diversification Mitochondrial genome
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Development of the A&GBE base editor for efficiently generating abundant genetic variation in rice
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作者 Wenhui Zhang Yaqi Xu +5 位作者 Jingxuan Cui Yingshuang Xue Lijie Zhang Wenjuan Wu Chong Wang Hui Zhang 《The Crop Journal》 SCIE CSCD 2024年第6期1801-1805,共5页
We have developed a dual base editor,rA&GBE,by fusing adenine and glycosylase base editors.It can induce up to eight types of mutations in T0-generation rice,including single-base conversion,simultaneous multiple-... We have developed a dual base editor,rA&GBE,by fusing adenine and glycosylase base editors.It can induce up to eight types of mutations in T0-generation rice,including single-base conversion,simultaneous multiple-base conversions,and InDels,using a single guide RNA.A-to-G and C-to-G/T conversions occur simultaneously on the same DNA strand.The rA&GBE system may prove useful for crop improvement and in planta direct evolution. 展开更多
关键词 CRISPR A&GBE Genetic variation RICE
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