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Erratum to"GenomeSyn:a bioinformatics tool for visualizing genome synteny and structural variations"[J.Genet.Genom.(2022)49,11741176]
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作者 Zu-Wen Zhou Zhi-Guang Yu +4 位作者 Xiao-Ming Huang Jin-Shen Liu Yi-Xiong Guo Ling-Ling Chen Jia-Ming Song 《Journal of Genetics and Genomics》 2025年第8期1068-1069,共2页
Fig.1.The GenomeSyn tool for visualizing genome synteny and characterizing structural variations.A:The first synteny visualization map showed the detailed information of two or three genomes and can display structural... Fig.1.The GenomeSyn tool for visualizing genome synteny and characterizing structural variations.A:The first synteny visualization map showed the detailed information of two or three genomes and can display structural variations and other annotation information.B:The second type of visualization map was simple and only showed the synteny relationship between the chromosomes of two or three genomes.C:Multiplatform general GenomeSyn submission page,applicable to Windows,MAC and web platforms;other analysis files can be entered in the"other"option.The publisher would like to apologise for any inconvenience caused. 展开更多
关键词 two three genomes structural variations synteny relationship genomesyn visualizing genome synteny characterizing structural variationsa genome synteny synteny visualization map
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Epigenetic variation in maize agronomical traits for breeding and trait improvement Author links open overlay panel 被引量:1
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作者 Daolei Zhang Yujun Gan +1 位作者 Liang Le Li Pu 《Journal of Genetics and Genomics》 2025年第3期307-318,共12页
Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional bree... Epigenetics-mediated breeding(epibreeding)involves engineering crop traits and stress responses through the targeted manipulation of key epigenetic features to enhance agricultural productivity.While conventional breeding methods raise concerns about reduced genetic diversity,epibreeding propels crop improvement through epigenetic variations that regulate gene expression,ultimately impacting crop yield.Epigenetic regulation in crops encompasses various modes,including histone modification,DNA modification,RNA modification,non-coding RNA,and chromatin remodeling.This review summarizes the epigenetic mechanisms underlying major agronomic traits in maize and identifies candidate epigenetic landmarks in the maize breeding process.We propose a valuable strategy for improving maize yield through epibreeding,combining CRISPR/Cas-based epigenome editing technology and Synthetic Epigenetics(SynEpi).Finally,we discuss the challenges and opportunities associated with maize trait improvement through epibreeding. 展开更多
关键词 Epibreeding Epigenetic variation Agronomical traits Epigenome editing Synthetic epigenetics
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Role of variation coefficient of stone density in determining success of shock wave lithotripsy in urinary calculi 被引量:1
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作者 Nadeem Iqbal Aisha Hasan +2 位作者 Sajid Iqbal Sadaf Noureen Saeed Akhter 《World Journal of Nephrology》 2025年第1期110-118,共9页
BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free r... BACKGROUND Various stone factors can affect the net results of shock wave lithotripsy(SWL).Recently a new factor called variation coefficient of stone density(VCSD)is being considered to have an impact on stone free rates.AIM To assess the role of VCSD in determining success of SWL in urinary calculi.METHODS Charts review was utilized for collection of data variables.The patients were subjected to SWL,using an electromagnetic lithotripter.Mean stone density(MSD),stone heterogeneity index(SHI),and VCSD were calculated by generating regions of interest on computed tomography(CT)images.Role of these factors were determined by applying the relevant statistical tests for continuous and categorical variables and a P value of<0.05 was gauged to be statistically significant.RESULTS There were a total of 407 patients included in the analysis.The mean age of the subjects in this study was 38.89±14.61 years.In total,165 out of the 407 patients could not achieve stone free status.The successful group had a significantly lower stone volume as compared to the unsuccessful group(P<0.0001).Skin to stone distance was not dissimilar among the two groups(P=0.47).MSD was significantly lower in the successful group(P<0.0001).SHI and VCSD were both significantly higher in the successful group(P<0.0001).CONCLUSION VCSD,a useful CT based parameter,can be utilized to gauge stone fragility and hence the prediction of SWL outcomes. 展开更多
关键词 Computed tomography Shock wave lithotripsy Stone heterogeneity variation coefficient of stone density Kidney stones
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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A Robust GNSS Navigation Filter Based on Maximum Correntropy Criterion with Variational Bayesian for Adaptivity 被引量:1
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作者 Dah-Jing Jwo Yi Chang Ta-Shun Cho 《Computer Modeling in Engineering & Sciences》 2025年第3期2771-2789,共19页
In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenario... In this paper,an advanced satellite navigation filter design,referred to as the Variational Bayesian Maximum Correntropy Extended Kalman Filter(VBMCEKF),is introduced to enhance robustness and adaptability in scenarios with non-Gaussian noise and heavy-tailed outliers.The proposed design modifies the extended Kalman filter(EKF)for the global navigation satellite system(GNSS),integrating the maximum correntropy criterion(MCC)and the variational Bayesian(VB)method.This adaptive algorithm effectively reduces non-line-of-sight(NLOS)reception contamination and improves estimation accuracy,particularly in time-varying GNSS measurements.Experimental results show that the proposed method significantly outperforms conventional approaches in estimation accuracy under heavy-tailed outliers and non-Gaussian noise.By combining MCC with VB approximation for real-time noise covariance estimation using fixed-point iteration,the VBMCEKF achieves superior filtering performance in challenging GNSS conditions.The method’s adaptability and precision make it ideal for improving satellite navigation performance in stochastic environments. 展开更多
关键词 Maximum correntropy criterion variational Bayesian extended Kalman filter GNSS
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A Review on Modeling Environmental Loading Effects and Their Contributions to Nonlinear Variations of Global Navigation Satellite System Coordinate Time Series 被引量:1
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作者 Zhao Li Weiping Jiang +3 位作者 Tonie van Dam Xiaowei Zou Qusen Chen Hua Chen 《Engineering》 2025年第4期26-37,共12页
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at... Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050. 展开更多
关键词 Environmental loading Global navigation satellite system Nonlinear variations Time series analysis Surface mass distribution Green’s function Spherical harmonic function
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The Minimal Affine Total Variation in Minkowski Spaces
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作者 MOU Shuang 《数学进展》 北大核心 2025年第1期164-176,共13页
In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total vari... In this paper,we use the solution of the even functional Minkowski problem to show that there is a minimizing affine Minkowski total variation of the function of bounded variation.Moreover,for the Minkowski total variation,we use the method of convexation to establish the same conclusion as the convex body space. 展开更多
关键词 convex body minimal surface area Minkowski space bounded variation
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Convergence of a New Bregman Projection Method with a Self-adaptive Stepsize for Solving Monotone Inclusion Problems and Variational Inequality Problems in Reflexive Banach Spaces
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作者 CHEN Lulu CAI Gang 《数学进展》 北大核心 2025年第1期141-163,共23页
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.... The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms. 展开更多
关键词 Bregman distance variational inequality monotone inclusion maximal operator reflexive Banach space
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Geometric Morphometric Analysis of Body Shape Variation in Glossogobius giuris from Lake Mainit,Agusan del Norte,Philippines
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作者 Cresencio C.Cabuga,Jr. Ana Marie D.Empeño Jojean Marie D.Pondang 《Research in Ecology》 2025年第2期144-158,共15页
Most fish exhibit remarkable morphological diversity,which is often influenced by genetic variation and ecological pressures.Consequently,these are the outcomes of organisms’responses to their environment.Meanwhile,m... Most fish exhibit remarkable morphological diversity,which is often influenced by genetic variation and ecological pressures.Consequently,these are the outcomes of organisms’responses to their environment.Meanwhile,modern morphometrics can quantify shape variation within species of the same group.This study aims to determine the body shape variation of Glossogobius giuris from Lake Mainit,Agusan Del Norte,Philippines.60 adult,uniform-sized fish samples were collected and subjected to standardized laboratory procedures.Further,the samples were digitized for 16 homologous landmark points and loaded into Symmetry Asymmetry Geometric Data(SAGE)Software.Across the tested factors—individuals,sides,and individual x sides—result shows that shape variations among individuals were highly significant(F=2.1045,p<0.0001),along with among males(F=3.2711,p<0.0001).Females exhibited higher Fluctuating Asymmetry(FA)(F=18.99,p<0.0001)compared to males(F=7.0964,p<0.0001).It suggests morphological shape differences across the sexes,and the shape variation observed could be a response to environmental perturbations.Shape variations were associated with swimming,food hunting,and predator defense.Moreover,Principal Component Analysis(PCA)demonstrates higher scores of FA in females(81.96%)than in males(74.76%).It was noticed that females had a high fluctuating asymmetry.It might be due to various physiological and ecological pressures compared to males.The observed levels of directional and fluctuating asymmetry in males and females,respectively,may indicate sex-linked morphological and developmental processes,which are important to consider in ecological or evolutionary contexts.Thus,utilizing geometric morphometrics can depict subtle differences across the same populations. 展开更多
关键词 Caraga Region Ecology Freshwater Fish Landmarks LIMNOLOGY PHENOTYPES Shape variation
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An assessment of atmospheric concentrations and spatiotemporal variation of BTEX and associated pollutants in India
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作者 Sruthi Jayaraj S.M.Shiva Nagendra 《Journal of Environmental Sciences》 2025年第4期230-245,共16页
Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air... Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air quality.BTEX exposure is a matter of grave concern in India owing to the growing vehicular and development activities,necessitating the assessment of atmospheric concentrations and their spatial variation.This paper presents a comprehensive assessment of ambient concentrations and spatiotemporal variations of BTEX in India.The study investigates the correlation of BTEX with other criteria pollutants andmeteorological parameters,aiming to identify interrelationships and diagnostic indicators for the source characterization of BTEX emissions.Additionally,the paper categorizes various regions in India according to the Air Quality Index(AQI)based on BTEX pollution levels.The results reveal that the northern zone of India exhibits the highest levels of BTEX pollution compared to central,eastern,and western regions.In contrast,the southern zone experiences the least pollution with BTEX.Seasonal analysis indicates that winter and postmonsoon periods,characterized by lower temperatures,are associated with higher BTEX levels due to the accumulation of localized emissions.When comparing the different zones in India,high traffic emissions and localized activities,such as solvent use and solvent evaporation,are found to be the primary sources of BTEX.The findings of the current study aid in source characterization and identification,and better understanding of the region’s air quality problems,which helps in the development of focused BTEX pollution reduction and control strategies. 展开更多
关键词 VOCS BTEX INDIA AQI Spatiotemporal variation
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Day-to-day variation in chlorophyll fluorescence parameters of northern and southern silver birch in a common garden
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作者 Olusegun Olaitan Akinyemi JaroslavČepl +4 位作者 Sarita Keski-Saari Jan Stejskal Ivana Tomášková Markku Keinänen Sari Kontunen-Soppela 《Journal of Forestry Research》 2025年第2期108-120,共13页
We used fast chlorophyll fluorescence transients(OJIP) to study provenance-related differences in photosynthetic performance and the magnitude of day-to-day chlorophyll fluorescence(ChlF) variation in northern(67°... We used fast chlorophyll fluorescence transients(OJIP) to study provenance-related differences in photosynthetic performance and the magnitude of day-to-day chlorophyll fluorescence(ChlF) variation in northern(67°N)and southern(62°N) silver birches in a common garden at62°N.ChlF transients were measured five times during two weeks in the middle of summer to avoid seasonal variation.Differences in growth and leaf morphological traits between the provenances were also examined.The northern trees had higher chlorophyll content,larger leaf areas,and higher leaf fresh and dry mass than the southern trees,but the leaf mass per area did not differ between the provenances.The southern trees were taller and showed higher annual shoot growth than the northern trees.For all the ChlF parameters,day-to-day variation was significant and followed the same pattern for both provenances with no significant provenance ×day interaction,suggesting a similar response to environmental variation.The northern provenance had higher values in parameters related to the reduction of end electron acceptors at the Photosystem I(PSI) acceptor side as probed by ChlF.This and higher values for performance indices PI_(abs) and PI_(tot) in northern than in southern trees suggest higher photosynthetic performance of northern trees in line with the latitudinal compensation strategy.Provenance differences in these parameters increased towards the end of the measurement period,suggesting preparation for earlier growth cessation in northern trees triggered by the shortening day length.The study shows that provenance differences in ChlF can be relatively stable regardless of environmental variation but might be influenced by physiological alterations in preparation for future changes in environmental conditions. 展开更多
关键词 JIP test Betula pendula PROVENANCES Intra-annual variation CHLOROPHYLL Leaf mass per area LMA Growth
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Variation and Reconstruction of Zhuge Liang’s Images in Three Kingdoms Translated by Moss Roberts
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作者 YI Zi-ning 《Journal of Literature and Art Studies》 2025年第5期366-374,共9页
As a classic novel,San Guo Yan Yi raises a crucial cross-cultural communication question:how can Western readers accurately and objectively understand Zhuge Liang’s image in its overseas translation?Influenced by cul... As a classic novel,San Guo Yan Yi raises a crucial cross-cultural communication question:how can Western readers accurately and objectively understand Zhuge Liang’s image in its overseas translation?Influenced by cultural context disparities and the intervention of the translator’s subjectivity,Moss Roberts has boldly transformed and reshaped Zhuge Liang’s traditionally-perceived image.In Three Kingdoms,from the image of an omnipotent wise man,a benevolent person,and a loyal and unwavering sage,Moss Roberts constructs images of Zhuge Liang who,while possessing genuine talent and knowledge,is also narrow-minded,jealous of the able and virtuous,and has a tinge of hypocrisy,thus creating a strong tragic implication.Through comparisons,this study aims to provide a new dimension for Zhuge Liang’s image,offering references for the study of cross-cultural translation of Chinese classical literature,deepening the understanding of how cultural identities are negotiated in translation. 展开更多
关键词 Three Kingdoms Moss Roberts Zhuge Liang variation RECONSTRUCTION
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Natural variation of CT2 affects the embryo/kernel weight ratio in maize
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作者 Yumin Zhang Sihan Zhen +9 位作者 Chunxia Zhang Jie Zhang Xiaoqing Shangguan Jiawen Lu Qingyu Wu Lynnette M.A.Dirk A.Bruce Downie Guoying Wang Tianyong Zhao Junjie Fu 《Journal of Genetics and Genomics》 2025年第3期432-440,共9页
Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we id... Embryo size is a critical trait determining not only grain yield but also the nutrition of the maize kernel.Up to the present,only a few genes have been characterized affecting the maize embryo/kernel ratio.Here,we identify 63 genes significantly associated with maize embryo/kernel weight ratio using a genome-wide association study(GWAS).The peak GWAS signal shows that the natural variation in Zea mays COMPACT PLANT2(CT2),encoding the heterotrimeric G proteinαsubunit,is significantly associated with the Embryo/Kernel Weight Ratio(EKWR).Further analyses show that a missense mutation of CT2 increases its enzyme activity and associates with EKWR.The function of CT2 on affecting embryo/kernel weight ratio is further validated by the characterization of two ct2 mutants,for which EKWR is significantly decreased.Subsequently,the key downstream genes of CT2 are identified by combining the differential expression analysis of the ct2 mutant and quantitative trait transcript analysis in the GWAS population.In addition,the allele frequency spectrum shows that CT2 was under selective pressure during maize domestication.This study provides important genetic insights into the natural variation of maize embryo/kernel weight ratio,which could be applied in future maize breeding programs to improve grain yield and nutritional content. 展开更多
关键词 MAIZE Embryo size GWAS CT2 Natural variation
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Genome-wide profiling of polymorphic short tandem repeats and their influence on gene expression and trait variation in diverse rice populations
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作者 Xiyu Tan Wanyong Zeng +7 位作者 Yujian Yang Zhansheng Lin Fuquan Li Jianhong Liu Shaotong Chen Yao-Guang Liu Weibo Xie Xianrong Xie 《Journal of Genetics and Genomics》 2025年第6期733-746,共14页
Short tandem repeats(STRs)modulate gene expression and contribute to trait variation.However,a systematic evaluation of the genomic characteristics of STRs has not been conducted,and their influence on gene expression... Short tandem repeats(STRs)modulate gene expression and contribute to trait variation.However,a systematic evaluation of the genomic characteristics of STRs has not been conducted,and their influence on gene expression in rice remains unclear.Here,we construct a map of 137,629 polymorphic STRs in the rice(Oryza sativa L.)genome using a population-scale resequencing dataset.A genome-wide survey encompassing 4726 accessions shows that the occurrence frequency,mutational patterns,chromosomal distribution,and functional properties of STRs are correlated with the sequences and lengths of repeat motifs.Leveraging a transcriptome dataset from 127 rice accessions,we identify 44,672 expression STRs(eSTRs)by modeling gene expression in response to the length variation of STRs.These eSTRs are notably enriched in the regulatory regions of genes with active transcriptional signatures.Population analysis identifies numerous STRs that have undergone genetic divergence among different rice groups and 1726 tagged STRs that may be associated with agronomic traits.By editing the(ACT)_(7) STR in OsFD1 promoter,we further experimentally validate its role in regulating gene expression and phenotype.Our study highlights the contribution of STRs to transcriptional regulation in plants and establishes the foundation for their potential use as alternative targets for genetic improvement. 展开更多
关键词 Gene expression Genomic variation Rice Short tandem repeat STR Transcriptional regulation
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Structural variation in Heinong 531 soybean genome underlies yield and resistance traits
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作者 Yu Tian Jia You +8 位作者 Zihao Zheng Hao Zhang Shiyu Guo Xueqing Wang Jinrong Li Lichun Huang Jiajun Wang Ying-hui Li Li-juan Qiu 《The Crop Journal》 2025年第5期1574-1584,共11页
Soybean(Glycine max)is a globally important crop that serves as a primary source of edible oil and protein for both humans and animals.Cultivated soybean varieties exhibit considerable genetic diversity depending on t... Soybean(Glycine max)is a globally important crop that serves as a primary source of edible oil and protein for both humans and animals.Cultivated soybean varieties exhibit considerable genetic diversity depending on their geographical origin.Heinong 531(HN531)is an elite cultivar that was released in China in June 2021 with 22.34%seed oil,high resistance to soybean cyst nematode(SCN)race 3,and enhanced yield.However,the genetic basis for these desirable agronomic traits is unclear.In this study,we generated a high-quality genome assembly for HN531 and used it to systematically analyze genes related to agronomic traits such as resistance to SCN.The assembled genome spans 981.20 Mb,featuring a contig N50 of 19.47 Mb,and contains 58,151 predicted gene models.Pan-genomic comparison with 27 previously reported soybean genomes revealed 95,071 structural variants(SVs)of>50 bp,of which 602 were HN531-specific.Furthermore,we identified a copy number variation at rhg1 that underlies resistance to SCN,and we found elite alleles of functional genes underlying important agronomic traits such as seed oil content,adaptability,and yield.This high-quality HN531 genome can be used to explore the genetic basis for the excellent agronomic traits of this cultivar,and is a valuable resource for breeders aiming to improve HN531 and related cultivars. 展开更多
关键词 SOYBEAN Genome assembly Structural variation R genes SCN
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Structural variation-based and gene-based pangenome construction reveals untapped diversity of hexaploid wheat
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作者 Hong Cheng Lingpeng Kong +7 位作者 Kun Zhu Hang Zhao Xiuli Li Yanwen Zhang Weidong Ning Mei Jiang Bo Song Shifeng Cheng 《Journal of Genetics and Genomics》 2025年第6期774-785,共12页
Increasing number of structural variations(SVs)have been identified as causative mutations for diverse agronomic traits.However,the systematic exploration of SVs quantity,distribution,and contribution in wheat was lac... Increasing number of structural variations(SVs)have been identified as causative mutations for diverse agronomic traits.However,the systematic exploration of SVs quantity,distribution,and contribution in wheat was lacking.Here,we report high-quality gene-based and SV-based pangenomes comprising 22 hexaploid wheat assemblies showing a wide range of chromosome size,gene number,and TE component,which indicates their representativeness of wheat genetic diversity.Pan-gene analyses uncover 140,261 distinct gene families,of which only 23.2%are shared in all accessions.Moreover,we build a∼16.15 Gb graph pangenome containing 695,897 bubbles,intersecting 5132 genes and 230,307 cis-regulatory regions.Pairwise genome comparisons identify∼1,978,221 non-redundant SVs and 497 SV hotspots.Notably,the density of bubbles as well as SVs show remarkable aggregation in centromeres,which probably play an important role in chromosome plasticity and stability.As for functional SVs exploration,we identify 2769 SVs with absolute relative frequency differences exceeding 0.7 between spring and winter growth habit groups.Additionally,several reported functional genes in wheat display complex structural graphs,for example,PPD-A1,VRT-A2,and TaNAAT2-A.These findings deepen our understanding of wheat genetic diversity,providing valuable graphical pangenome and variation resources to improve the efficiency of genome-wide association mapping in wheat. 展开更多
关键词 Wheat Pangenome Structural variation Centromere plasticity Growth habit
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Monthly variations in nutrient utilization along 45°E transect in the Cosmonaut Sea, East Antarctica during austral summer
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作者 Xufeng Yang Dong Li +12 位作者 Jun Zhao Cai Zhang Changfeng Zhu Shunan Cao Guangfu Luo Gaojing Fan Yongming Sun Ji Hu Haifeng Zhang Peisong Yu Weiping Sun Jianming Pan Jianfeng He 《Acta Oceanologica Sinica》 2025年第4期75-89,共15页
Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is sti... Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is still unclear,partly due to lack of data spanning the entire summer.In this study,nitrate,phosphate,and silicate combined with temperature,salinity,and apparent oxygen utilization(AOU)were analyzed along 45°E in the Cosmonaut Sea during December 2019,January 2021,and February 2022.The variations in nutrient utilization in the euphotic layer were studied using biogeochemical tracers,and seasonal nutrient depletion was also estimated.The results showed that nutrient distribution varied significantly from December to February.Significant positive correlations were observed for nitrate and silicate concentrations with salinity and AOU,indicating that nutrient distributions were mainly influenced by water mass and phytoplankton production.Increasing∆[N*]and decreasing∆[Si*]in the upper 50 m were observed south of 63.5°S from December to February,which possibly contributed to a progressive shift in dominant phytoplankton population from Phaeocystis antarctica to diatoms.The seasonal nutrient depletion generally increased from December to February.Moreover,the consumption of silicate substantially increased compared to nitrate,indicating that the abundance of diatoms was increasing with time during the austral summer.Our observations suggest that nutrient utilization status is closely related to phytoplankton community structure in the euphotic layer of the Cosmonaut Sea. 展开更多
关键词 NUTRIENT biogeochemical tracers seasonal depletion monthly variation Cosmonaut Sea
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Language Attitude and Language Variation:Empirical Study on Mandarin
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作者 LI Jin-feng ZHOU Yu-liang 《Journal of Literature and Art Studies》 2025年第4期329-333,共5页
This paper empirically studies the effects of attitudes towards Mandarin on Mandarin variation,and finds that both Mandarin emotional and value attitudes can effectively suppress Mandarin variation.Further research ha... This paper empirically studies the effects of attitudes towards Mandarin on Mandarin variation,and finds that both Mandarin emotional and value attitudes can effectively suppress Mandarin variation.Further research has found that the language attitudes of local residents have a stronger overall impact on Mandarin variation;The language attitude in small cities has a stronger impact on the variation of Mandarin. 展开更多
关键词 language attitude emotional attitude value attitude language variation MANDARIN
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Inter-and intraspecific variation in flight muscle fibers is associated with migratory timing
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作者 Shangmingyu Zhang Shane DuBay +3 位作者 Yuwen Cheng Zhehan Dong Zhengwei Liu Yongjie Wu 《Avian Research》 2025年第1期30-38,共9页
The life-history strategies of organisms are shaped by trade-offs among traits that influence survival,development,reproduction,and ultimately fitness.However,the specific physiological and environmental mechanisms dr... The life-history strategies of organisms are shaped by trade-offs among traits that influence survival,development,reproduction,and ultimately fitness.However,the specific physiological and environmental mechanisms driving population-level variation in phenotypic traits,particularly in relation to migratory adaptations,remain poorly understood.Elevational migration represents an adaptive behavior for mountain birds that offers a unique model to investigate adaptive phenotypes because of the diverse migratory strategies that have been observed within and between species.Flight muscles,as multifunctional organs,exhibit phenotypic variation that aligns with locomotor and thermoregulatory demands.Linking flight muscle phenotypes to migratory strategies can provide insights into inter-and intraspecific variation in migratory adaptations.In this study,we examined spring arrival dates at high-altitude breeding sites for three closely related high-altitude breeding birds in the mountains of Asia:Blue-fronted Redstart(Phoenicurus frontalis),Himalayan Bluetail(Tarsiger rufilatus),and Rufous-gorgeted Flycatcher(Ficedula strophiata).We analyzed relationships between arrival dates and phenotypic traits,including flight muscle physiology,morphology,and internal organ mass,alongside environmental effects on these traits.Our findings indicate that species arriving earlier encountered lower temperatures and exhibited reduced fiber cross-sectional areas coupled with higher fast oxidative glycolytic(FOG)fibers densities.Males displayed pronounced protandry and higher fast glycolytic(FG)fibers densities.Ambient temperature significantly influenced flight muscle phenotypes,highlighting intraspecific variation and the potential plasticity of flight muscle fibers as crucial mechanisms for adapting to migration strategies and environmental conditions.Additionally,this study underscores the potential role of sexual selection in shaping functional phenotypic variation,further advancing our understanding of adaptive strategies in high-altitude migratory birds. 展开更多
关键词 Elevational migration Intraspecific variation Muscle fiber PHENOTYPE Small-bodied birds
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Morphological Variation in Sichuan Spiny Frogs Along Geographic and Environmental Gradients
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作者 Jiahui SUN Haoxian LIN +1 位作者 Hong LI Junhua HU 《Asian Herpetological Research》 2025年第1期66-74,共9页
Understanding the ecogeographic mechanisms driving morphological variation is pivotal in biogeographic studies. However, patterns and determinants of such variation remain contentious, particularly in amphibians. Alth... Understanding the ecogeographic mechanisms driving morphological variation is pivotal in biogeographic studies. However, patterns and determinants of such variation remain contentious, particularly in amphibians. Although several hypotheses have been formulated and investigated in amphibians, their validity remains disputed with mixed support. Using the Sichuan spiny frog(Nanorana sichuanensis) as an indicator, we investigated the morphological variations across geographic and environmental gradients to explore the underlying ecogeographic mechanisms. We found that both the body size and limb characteristics of N.sichuanensis were not significantly related to latitude or elevation, suggesting that it did not follow Bergmann's or Allen's rules. Eye diameter decreased linearly with increasing elevation and latitude, whereas snout length increased with increasing elevation and latitude. Heat balance, endurance, seasonality, water availability, and primary productivity collectively explain body size variation. Hierarchical partitioning identified primary productivity and thermal excursion as the most influential factors, explaining significant variability in body size and other morphological features. Specifically, primary productivity accounted for 52.40% of the variation in body size, whereas thermal excursion had the greatest impact on eye diameter(36.23%) and snout length(72.17%). Based on body size and dimensionally reduced morphological features, our results identified ecogeographic patterns, assessed the validity of different hypotheses, and examined how environmental factors influence these morphological variations. More generally, our study offers comprehensive insights into the ecogeographic variation observed in mountain amphibians,provides a critical evaluation of existing ecogeographic hypotheses, and infers possible morphological adaptations in response to environmental change. 展开更多
关键词 Allen's rule Bergmann's rule ecogeographic rule environmental gradients morphological variation Nanorana sichuanensis
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