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Scale-space effect and scale hybridization in image intelligent recognition of geological discontinuities on rock slopes
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作者 Mingyang Wang Enzhi Wang +1 位作者 Xiaoli Liu Congcong Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1315-1336,共22页
Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understa... Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understanding the progressive damage mechanisms of slopes based on monitoring image data.Inspired by recent advances in computer vision,deep learning(DL)models have been widely utilized for image-based fracture identification.The multi-scale characteristics,image resolution and annotation quality of images will cause a scale-space effect(SSE)that makes features indistinguishable from noise,directly affecting the accuracy.However,this effect has not received adequate attention.Herein,we try to address this gap by collecting slope images at various proportional scales and constructing multi-scale datasets using image processing techniques.Next,we quantify the intensity of feature signals using metrics such as peak signal-to-noise ratio(PSNR)and structural similarity(SSIM).Combining these metrics with the scale-space theory,we investigate the influence of the SSE on the differentiation of multi-scale features and the accuracy of recognition.It is found that augmenting the image's detail capacity does not always yield benefits for vision-based recognition models.In light of these observations,we propose a scale hybridization approach based on the diffusion mechanism of scale-space representation.The results show that scale hybridization strengthens the tolerance of multi-scale feature recognition under complex environmental noise interference and significantly enhances the recognition accuracy of GD.It also facilitates the objective understanding,description and analysis of the rock behavior and stability of slopes from the perspective of image data. 展开更多
关键词 Image processing Geological discontinuities Deep learning MULTI-SCALE Scale-space theory Scale hybridization
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Morphological and molecular evidence for natural hybridization between Sorbus pohuashanensis and S. discolor (Rosaceae)
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作者 Yuxia Wu Xuedan Yu +4 位作者 Wei Tang Wenhua Yang Qidi Fu Yongqi Zheng Chuanhong Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期189-201,共13页
In overlapping distribution areas of Sorbus pohuashanensis and S.discolor in North China(Mount Tuoliang,Mount Xiling and Mount Baihua),Sorbus indi-viduals were found with pink fruit,which have never been recorded for ... In overlapping distribution areas of Sorbus pohuashanensis and S.discolor in North China(Mount Tuoliang,Mount Xiling and Mount Baihua),Sorbus indi-viduals were found with pink fruit,which have never been recorded for the flora of China.Fourteen morphological characters combined with four chloroplast DNA markers and internal transcribed spacer(ITS)were used to analyze the origin of the Sorbus individuals with pink fruits and their relationship to S.pohuashanensis and S.discolor.PCA,SDA and one-way(taxon)ANOVA of morphological characters provided convincing evidence of the hybrid ori-gin of Sorbus individuals with pink fruits based on a novel morphological character and many intermediate characters.Haplotype analysis based on four cpDNA markers showed that either S.pohuashanensis or S.discolor were maternal parents of Sorbus individuals with pink fruits.Incongru-ence of the position of Sorbus individuals with pink fruits between cpDNA and ITS in cluster trees supported by DNA sequence comparative analysis,implying former hybridiza-tion events between S.pohuashanensis and S.discolor.Mul-tiple hybridization events between S.pohuashanensis and S.discolor might have contributed to the generation of Sorbus individuals with pink fruits.This study has provided insights into hybridization between species of the same genus in sympatric areas,which is of great significance for the study of interspecific hybridization. 展开更多
关键词 hybridization ITS Chloroplast DNA Morphological characters SORBUS
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Enhanced and asymmetric signatures of hybridization at climatic margins: Evidence from closely related dioecious fig species
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作者 Jian-Feng Huang Clive T.Darwell Yan-Qiong Peng 《Plant Diversity》 SCIE CAS CSCD 2024年第2期181-193,共13页
Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where p... Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern Thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene flow.Signatures of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales. 展开更多
关键词 hybridization Heterospecific visitation FIG Pollinator wasp Asymmetric gene flow
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Cryptic divergences and repeated hybridizations within the endangered “living fossil” dove tree(Davidia involucrata) revealed by whole genome resequencing
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作者 Yumeng Ren Lushui Zhang +5 位作者 Xuchen Yang Hao Lin Yupeng Sang Landi Feng Jianquan Liu Minghui Kang 《Plant Diversity》 SCIE CAS CSCD 2024年第2期169-180,共12页
The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However... The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range.Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories. 展开更多
关键词 Davidia involucrata Cryptic lineage hybridization Population genomics Positive evolution
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Enhanced Redox Electrocatalysis in High‑Entropy Perovskite Fluorides by Tailoring d–p Hybridization
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作者 Xudong Li Zhuomin Qiang +4 位作者 Guokang Han Shuyun Guan Yang Zhao Shuaifeng Lou Yongming Zhu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期333-350,共18页
High-entropy catalysts featuring exceptional properties are,in no doubt,playing an increasingly significant role in aprotic lithium-oxygen batteries.Despite extensive effort devoted to tracing the origin of their unpa... High-entropy catalysts featuring exceptional properties are,in no doubt,playing an increasingly significant role in aprotic lithium-oxygen batteries.Despite extensive effort devoted to tracing the origin of their unparalleled performance,the relationships between multiple active sites and reaction intermediates are still obscure.Here,enlightened by theoretical screening,we tailor a high-entropy perovskite fluoride(KCoMnNiMgZnF_(3)-HEC)with various active sites to overcome the limitations of conventional catalysts in redox process.The entropy effect modulates the d-band center and d orbital occupancy of active centers,which optimizes the d–p hybridization between catalytic sites and key intermediates,enabling a moderate adsorption of LiO_(2)and thus reinforcing the reaction kinetics.As a result,the Li–O2 battery with KCoMnNiMgZnF_(3)-HEC catalyst delivers a minimal discharge/charge polarization and long-term cycle stability,preceding majority of traditional catalysts reported.These encouraging results provide inspiring insights into the electron manipulation and d orbital structure optimization for advanced electrocatalyst. 展开更多
关键词 Lithium-oxygen batteries KCoMnNiMgZnF_(3)-HEC perovskite fluoride Entropy effect Catalytic kinetics d-p orbital hybridization
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p-d Orbital Hybridization Engineered Single-Atom Catalyst for Electrocatalytic Ammonia Synthesis 被引量:1
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作者 Jingkun Yu Xue Yong Siyu Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期119-125,共7页
The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is challenging.Two-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising SACs.Up to now,... The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is challenging.Two-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising SACs.Up to now,the roles of individual metals,coordination atoms,and their synergy effect on the electroanalytic performance remain unclear.Therefore,in this work,a series of 2DMOFs with different metals and coordinating atoms are systematically investigated as electrocatalysts for ammonia synthesis using density functional theory calculations.For a specific metal,a proper metal-intermediate atoms p-d orbital hybridization interaction strength is found to be a key indicator for their NRR catalytic activities.The hybridization interaction strength can be quantitatively described with the p-/d-band center energy difference(Δd-p),which is found to be a sufficient descriptor for both the p-d hybridization strength and the NRR performance.The maximum free energy change(ΔG_(max))andΔd-p have a volcanic relationship with OsC_(4)(Se)_(4)located at the apex of the volcanic curve,showing the best NRR performance.The asymmetrical coordination environment could regulate the band structure subtly in terms of band overlap and positions.This work may shed new light on the application of orbital engineering in electrocatalytic NRR activity and especially promotes the rational design for SACs. 展开更多
关键词 first-principle calculations Nitrogen reduction p-d orbital hybridization single-atom catalysts
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Predicting the Results of RNA Molecular Specific Hybridization Using Machine Learning 被引量:3
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作者 Weijun Zhu Xiaokai Liu +1 位作者 Mingliang Xu Huanmei Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1384-1396,共13页
Ribonucleic acid(RNA)hybridization is widely used in popular RNA simulation software in bioinformatics.However limited by the exponential computational complexity of combin atorial problems,it is challenging to decide... Ribonucleic acid(RNA)hybridization is widely used in popular RNA simulation software in bioinformatics.However limited by the exponential computational complexity of combin atorial problems,it is challenging to decide,within an acceptable time,whether a specific RNA hybridization is effective.We hereby introduce a machine learning based technique to address this problem.Sample machine learning(ML)models tested in the training phase include algorithms based on the boosted tree(BT)random forest(RF),decision tree(DT)and logistic regression(LR),and the corresponding models are obtained.Given the RNA molecular coding training and testing sets,the trained machine learning models are applied to predict the classification of RNA hybridization results.The experiment results show that the op timal predictive accuracies are 96.2%,96.6%,96.0%and 69.8%for the RF,BT,DT and LR-based approaches,respectively,un der the strong constraint condition,compared with traditiona representative methods.Furthermore,the average computation efficiency of the RF,BT,DT and LR-based approaches are208679,269756,184333 and 187458 times higher than that o existing approach,respectively.Given an RNA design,the BT based approach demonstrates high computational efficiency and better predictive accuracy in determining the biological effective ness of molecular hybridization. 展开更多
关键词 Biological effectiveness boosted tree(BT) decision tree(DT) random forest(RF) RNA design SPECIFIC hybridization LOGISTIC regression(LR)
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Manipulating d-d orbital hybridization induced by Mo-doped Co_(9)S_(8) nanorod arrays for high-efficiency water electrolysis
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作者 Xue Zhou Jing Li +8 位作者 Guangyao Zhou Weiran Huang Yucan Zhang Jun Yang Huan Pang Mingyi Zhang Dongmei Sun Yawen Tang Lin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期592-600,I0015,共10页
Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic performance.Herein,we demonstrate an ingenious d-d orbital hybridization concept ... Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic performance.Herein,we demonstrate an ingenious d-d orbital hybridization concept to construct Mo-doped Co_(9)S_(8) nanorod arrays aligned on carbon cloth(CC)substrate(abbreviated as Mo-Co_(9)S_(8)@CC hereafter)as a high-efficiency bifunctional electrocatalyst toward water electrolysis.It has experimentally and theoretically validated that the 4d-3d orbital coupling between Mo dopant and Co site can effectively optimize the H_(2)O activation energy and lower H^(*)adsorption energy barrier,thereby leading to enhanced hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)activities.Thanks to the unique electronic and geometrical advantages,the optimized Mo-Co_(9)S_(8)@CC with appropriate Mo content exhibits outstanding bifunctional performance in alkaline solution,with the overpotentials of 75 and 234 mV for the delivery of a current density of 10 mA cm^(-2),small Tafel slopes of 53.8 and 39.9 mV dec~(-1)and long-term stabilities for at least 32 and 30 h for HER and OER,respectively.More impressively,a water splitting electrolylzer assembled by the self-supported Mo-Co_(9)S_(8)@CC electrode requires a low cell voltage of 1.53 V at 10 mA cm^(-2)and shows excellent stability and splendid reversibility,demonstrating a huge potential for affordable and scalable electrochemical H_(2) production.The innovational orbital hybridization strategy for electronic regulation herein provides an inspirable avenue for developing progressive electrocatalysts toward new energy systems. 展开更多
关键词 d-d orbital hybridization Transition metal sulfides Nanorods arrays Water electrolysis
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Cryptic diversity and rampant hybridization in annual gentians on the Qinghai-Tibet Plateau revealed by population genomic analysis
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作者 Peng-Cheng Fu Qiao-Qiao Guo +2 位作者 Di Chang Qing-Bo Gao Shan-Shan Sun 《Plant Diversity》 SCIE CAS CSCD 2024年第2期194-205,共12页
Understanding the evolutionary and ecological processes involved in population differentiation and speciation provides critical insights into biodiversity formation. In this study, we employed 29,865 single nucleotide... Understanding the evolutionary and ecological processes involved in population differentiation and speciation provides critical insights into biodiversity formation. In this study, we employed 29,865 single nucleotide polymorphisms(SNPs) and complete plastomes to examine genomic divergence and hybridization in Gentiana aristata, which is endemic to the Qinghai-Tibet Plateau(QTP) region. Genetic clustering revealed that G. aristata is characterized by geographic genetic structures with five clusters(West, East, Central, South and North). The West cluster has a specific morphological character(i.e., blue corolla) and higher values of FSTcompared to the remaining clusters, likely the result of the geological barrier formed by the Yangtze River. The West cluster diverged from the other clusters in the Early Pliocene;these remaining clusters diverged from one another in the Early Quaternary. Phylogenetic reconstructions based on SNPs and plastid data revealed substantial cyto-nuclear conflicts. Genetic clustering and D-statistics demonstrated rampant hybridization between the Central and North clusters,along the Bayankala Mountains, which form the geological barrier between the Central and North clusters. Species distribution modeling demonstrated the range of G. aristata expanded since the Last Interglacial period. Our findings provide genetic and morphological evidence of cryptic diversity in G. aristata, and identified rampant hybridization between genetic clusters along a geological barrier.These findings suggest that geological barriers and climatic fluctuations have an important role in triggering diversification as well as hybridization, indicating that cryptic diversity and hybridization are essential factors in biodiversity formation within the QTP region. 展开更多
关键词 Gentiana aristata Hybrid zone Qinghai-Tibet Plateau PLASTOME Nuclear SNPs
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Asymmetric orbital hybridization in Zn-doped antiperovskite Cu_(1-x)Zn_(x)NMn_(3)enables highly efficient electrocatalytic hydrogen production
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作者 Yuxiang Yan Yuxin Cao +9 位作者 Zhichao Wang Ka Wang Hengdong Ren Shaoqi Zhang Yi Wang Jian Chen Yong Zhou Lizhe Liu Jun Dai Xinglong Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期304-312,I0008,共10页
Rational design of efficient and robust earth-abundant alkaline hydrogen evolution reaction(HER)catalysts is a key factor for developing energy conversion technologies.Currently,antiperovskite nitride CuNMn_(3)has gar... Rational design of efficient and robust earth-abundant alkaline hydrogen evolution reaction(HER)catalysts is a key factor for developing energy conversion technologies.Currently,antiperovskite nitride CuNMn_(3)has garnered significant interest due to its remarkable properties such as negative/zero thermal expansion and magnetocaloric effects.However,when utilized as hydrogen evolution catalysts,it encounters large challenge resulting from excessively strong/weak interactions with adsorbed H on Mn/Cu active sites,which leads to low HER activity.In this study,we introduce an asymmetric orbital hybridization strategy in Zn-doped Cu_(1-x)Zn_(x)NMn_(3)by leveraging the localization of Zn electronic states to reconfigure the electronic structures of Cu and Mn,thereby reducing the energy barrier for water dissociation and optimizing Cu and Mn active sites for hydrogen adsorption and H_(2)production.Electrochemical evaluations reveal that Cu_(0.85)Zn_(0.15)NMn_(3)with x=0.15 demonstrates exceptional electrocatalytic activity in alkaline electrolytes.A low overpotential of 52 mV at 10 mA cm^(-2)and outstanding stability over a 150-h test period are achieved,surpassing commercial Pt/C.This research offers a novel strategy for enhancing HER performance by modulating asymmetric hybridization of electron orbitals between multiple metal atoms within a material structure. 展开更多
关键词 Cu_(1-x)ZnxNMn_(3) Asymmetric orbital hybridization Hydrogen adsorption Hydrogen production
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An Alternative Analysis on Nilsson-Ehle’s Hybridization Experiment in Wheat —Theory of Dual Multiple Factors and Three Normal Distributions on Quantitative Inheritance (Continuation)
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作者 Tingzhen Zhang Xiaoming Jia Zhao Xu 《Applied Mathematics》 2018年第8期1005-1014,共10页
In this paper, an analysis on Nilsson-Ehle’s hybridization experiment in wheat was done by means of self-fertilization method along with the pericarp inheritance. It showed that because seeds of wheat were coated wit... In this paper, an analysis on Nilsson-Ehle’s hybridization experiment in wheat was done by means of self-fertilization method along with the pericarp inheritance. It showed that because seeds of wheat were coated with 2n tissues of mother’s body, the grain colors were determined by mother’s genotype. The color of the F1 grains in this experiment was old red. The phenotypes of the F2 grains were uniformly medium red and did not segregate. Grains in the F3 generation segregated in the ratio 6 red (varying intensities of red) to 1 white with a definite probability respectively. This is the consequence of additive effect of 3 gene pairs and belongs to discrete distribution rather than continuous distribution. Therefore, the multiple-gene hypothesis based on this experiment cannot solve the continuous variations in inheritance of quantitative characters. 展开更多
关键词 WHEAT hybridization 3 Gene PAIRS Additive Effect Grain Color PERICARP INHERITANCE Delayed INHERITANCE Discrete Distribution
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In situ hybridization detection of persistent infection and viral RNA distribution in laboratory rats with hemorrhagic fever with renal syndrome virus
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作者 林中清 杨守京 刘颜仿 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第1期30-33,38,共5页
Digoxigenin-labelled Hantaan specific cDNA probes were used in the present study for in situ hybridization detection of hemorrhagic fever with renal syndrome virus(HFRSV) persistent infection and viral RNA distributio... Digoxigenin-labelled Hantaan specific cDNA probes were used in the present study for in situ hybridization detection of hemorrhagic fever with renal syndrome virus(HFRSV) persistent infection and viral RNA distribution in naturally infected laboratory rat 展开更多
关键词 HEMORRHAGIC FEVER with RENAL syndrome virus RNA PERSISTENT infection hybridization in SITU Rats
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Fiber-fluorescence in situ hybridization analyses as a diagnostic application for orientation of microduplications
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作者 Toshiyuki Yamamoto Shino Shimada Keiko Shimojima 《World Journal of Medical Genetics》 2013年第2期5-8,共4页
Microduplications are normally invisible under microscopy and were not recognized before chromosomal microarray testing was available. Although it is difficult to confirm the orientation of duplicated segments by stan... Microduplications are normally invisible under microscopy and were not recognized before chromosomal microarray testing was available. Although it is difficult to confirm the orientation of duplicated segments by standard fluorescence in situ hybridization(FISH), our data indicates that fiber-FISH analysis has the potential to reveal the orientation of duplicated and triplicated segments of chromosomes. Recurrent microduplications reciprocal to microdeletions show tandem orientations of the duplicated segments, which is consistent with a non-allelic homologous recombination mechanism. Several random duplications showed tandem configurations and inverted duplications are rare. Further analysis is required to fully elucidate the basic mechanisms underlying such duplications/triplications. 展开更多
关键词 CHROMOSOMAL microarray testing Copy number variation Fiber-fluorescence in SITU hybridization MICRODUPLICATION Tandem ORIENTATION
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Hybridization Effects Revealed by Angle-Resolved Photoemission Spectroscopy in Heavy-Fermion Ce2IrIn8
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作者 Haijiang Liu Yuanji Xu +9 位作者 Yigui Zhong Jianyu Guan Lingyuan Kong Junzhang Ma Yaobo Huang Qiuyun Chen Genfu Chen Ming Shi Yi-feng Yang Hong Ding 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第9期36-40,共5页
We utilize high-resolution resonant angle-resolved photoemission spectroscopy(ARPES)to study the band structure and hybridization effect of the heavy-fermion compound Ce2 IrIn8.We observe a nearly flat band at the bin... We utilize high-resolution resonant angle-resolved photoemission spectroscopy(ARPES)to study the band structure and hybridization effect of the heavy-fermion compound Ce2 IrIn8.We observe a nearly flat band at the binding energy of 7 meV below the coherent temperature Tcoh^40 K,which characterizes the electrical resistance maximum and indicates the onset temperature of hybridization.However,the Fermi vector and the Fermi surface volume have little change around Tcoh,which challenges the widely believed evolution from a hightemperature small Fermi surface to a low-temperature large Fermi surface.Our experimental results of the band structure fit well with the density functional theory plus dynamic mean-field theory calculations. 展开更多
关键词 ARPES hybridization EFFECTS REVEALED by Angle-Resolved PHOTOEMISSION Spectroscopy in HEAVY-FERMION Ce2IrIn8 Ce
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Enhancement in Elastic Modulus of GFRP Bars by Material Hybridization
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作者 Dong-Woo Seo Ki-Tae Park +1 位作者 Young-Jun You Hyeong-Yeol Kim 《Engineering(科研)》 2013年第11期865-869,共5页
Fiber reinforced polymer (FRP) reinforcing bars for concrete structure has been extensively investigated for last two decades and a number of FRP bars are commercially available. However, one of shortcomings of the ex... Fiber reinforced polymer (FRP) reinforcing bars for concrete structure has been extensively investigated for last two decades and a number of FRP bars are commercially available. However, one of shortcomings of the existing FRP bars is its low elastic modulus, if glass fibers are used (i.e., GFRP). The main objective of this study using the concept of material hybridization is to develop a viable hybrid FRP bar for concrete structures, especially for marine and port con- crete structures. The purposes of hybridization are to increase the elastic modulus of GFRP bar with acceptable tensile strength. Two types of hybrid GFRP bar were considered in the development: GFRP crust with steel core and GFRP bar with steel wires dispersed over the cross-section. Using E-glass fibers and unsaturated polyester resins, the hybrid GFRP bar samples of 13 mm in diameter were pultruded and tested for tensile properties. The effect of hybridization on tensile properties of GFRP bars was evaluated by comparing the results of tensile test with those of non-hybrid GFRP bars. The results of this study indicated that the elastic modulus of the hybrid GFRP bar was increased by up to 270 percent by the material hybridization. The results of the test and the future recommendations are summarized in this paper. To ensure long-term durability of the hybrid GFRP bars in waterfront structure applications, the individual and combined effects of environmental conditions on hybrid GFRP rebar itself as well as on the interface between rebar and concrete should be accessed. 展开更多
关键词 FRP Glass Fibers TENSILE Test Elastic MODULUS PULTRUSION MATERIAL hybridization Marine Structures
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Genomic insights into hybridization in a localized region of sympatry between pewee sister species(Contopus sordidulus × C. virens) and their chromosomal patterns of differentiation
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作者 Joseph D.Manthey Mark B.Robbins 《Chinese Birds》 CSCD 2016年第1期48-55,共8页
Background: The Great Plains of the United States includes a large number of hybrid and contact zones between bird species. The amount of gene flow between sister species in these zones ranges from very rare hybridiza... Background: The Great Plains of the United States includes a large number of hybrid and contact zones between bird species. The amount of gene flow between sister species in these zones ranges from very rare hybridization events to widespread and prevalent introgression. Some of these avian systems have been studied extensively, while others have been indeterminate of whether hybridization exists in areas of sympatry. Using genomic-level approaches allows investigation of genomic patterns of hybridization and gene flow between species—or lack thereof.Methods: We investigated a narrow zone of sympatry in Nebraska, USA between pewee species(Contopus sordidulus and C. virens), for which no hybridization has been confirmed. We used thousands of single nucleotide polymorphisms to identify potential hybridization and investigate genomic patterns of differentiation between these two species.Results: We found evidence of multiple hybrid individuals in the contact zone. Little genomic variation was fixed between species, but a large proportion had differentiated allele frequencies between species. There was a positive relationship between genetic differentiation and chromosome size.Conclusions: We provided the first conclusive evidence of hybridization between C. sordidulus and C. virens, in a region where secondary contact likely occurred due to human disturbance and habitat modification. The genomic patterns of differentiation affirm that these species split in the relatively recent past. Finally, the relationship of chromosome size and genetic differentiation may have resulted from differential rates of chromosomal recombination in songbirds and genetic differentiation between species largely due to genetic drift(possibly in concert with selection). 展开更多
关键词 Contact ZONE Hybrid ZONE hybridization CHROMOSOMAL PATTERNS Next-generation sequencing Contopus North AMERICA
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Interspecific Hybridization between <i>Arisaema sikokianum</i>and <i>A. serratum</i>(Araceae) Confirmed through Nuclear and Chloroplast DNA Comparisons
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作者 Hiroshi Hayakawa Hidenori Hamachi +5 位作者 Kanako Matsuyama Yuko Muramatsu Yukio Minamiya Katsura Ito Jun Yokoyama Tatsuya Fukuda 《American Journal of Plant Sciences》 2011年第4期521-526,共6页
A morphologically intermediate plant between Arisaema sikokianum Franch. et Sav. and A. serratum (Thunb.) Schott has been newly found in Kochi Prefecture, Shikoku, Japan. The putative hybrid has the intermediate morph... A morphologically intermediate plant between Arisaema sikokianum Franch. et Sav. and A. serratum (Thunb.) Schott has been newly found in Kochi Prefecture, Shikoku, Japan. The putative hybrid has the intermediate morphological characteristics of the parental species. Molecular analysis using PCR-RFLP of internal transcribed spacer (ITS) in nuclear DNA (nrDNA) indicates that the putative hybrid has a combined pattern of the two putative parent species. Moreover, the sequence result of chloroplast DNA (cpDNA) of the putative hybrid was identical to that of A. sikokianum. These results suggest that the putative hybrid is a hybrid between A. sikokianum and A. serratum and that it was formed by interactive gene exchanging via pollens from A. serratum to A. sikokianum. It is the first record of a hybrid between A. sikokianum and A. serratum. 展开更多
关键词 ARACEAE ARISAEMA A. serratum A. sikokianum Chloroplast DNA Interspecific Hybrid Molecular Analysis NUCLEAR DNA
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Localization of keratin m RNA and collagen Ⅰm RNAin gastric cancerby in situ hybridization and hybridization electron microscopy 被引量:2
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作者 SU Chang Qing 1, QIU Hong 1 and ZHANG Yan 2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第6期527-530,共4页
关键词 KERATIN COLLAGEN in SITU hybridization nucleic acid STOMACH neoplasms mRNA
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Analytical consideration of the selectivity of oligonucleotide hybridization
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作者 M. R. Kabilov D. V. Pyshnyi 《Journal of Biophysical Chemistry》 2011年第2期75-91,共17页
Systematic analysis of factors determining efficiency in discrimination of a point substitution (SNP) within specific DNA sequences was carried out in the context of hybridization approach. There are two types of sele... Systematic analysis of factors determining efficiency in discrimination of a point substitution (SNP) within specific DNA sequences was carried out in the context of hybridization approach. There are two types of selectivity that are critical for the rational design of highly specific oligonucleotides probes. The first type is the real selectivity of hybridization (fa) that is the ratio of association degrees of targets with an oligonucleotide probe upon the perfect and imperfect complex formation. This type of selectivity reflects the level of discrimination between matched and mismatched signals, which is determined both by experimental conditions and the thermodynamics of oligonucleotide hybridization. The second parameter characterizing the efficiency of SNP discrimination is the limit selectivity of hybridization, which determines the utmost value of fa at a given temperature. This value can be calculated as the ratio of corresponding equilibrium association constants of perfect and imperfect complex formation determined purely by thermodynamics. We have shown that the fa function is the most reliable characteristic describing the hybridization selectivity. For the analytical system designed to reveal any type of perturbation in DNA (e.g. SNP or modification), there is usually a temperature at which fa has its maximum value. The dependency of the fa maximum on different experimental parameters as well as the structural characteristics of a probe are described in details. The results allowed us to postulate points of principle to rationally design the most selective probes on the basis of oli- gonucleotides or their derivatives. 展开更多
关键词 ALLELE Specific hybridization DUPLEX Stability OLIGONUCLEOTIDE Probes SNP Discrimination SPECIFICITY Thermodynamics
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THE IMMUNOHISTOCHEMISTRY AND IN SITU cDNA-mRNA HYBRIDIZATION OF CARBAMYL PHOSPHATE SYNTHETASE I IN ENZYME-ALTERED LIVER CELLS DURING CARCINOGENESIS 被引量:1
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作者 杨一平 丁濂 李士谔 《Chinese Medical Sciences Journal》 CAS CSCD 1990年第1期13-18,共6页
The changes of carbamyl phosphate synthetase I(CPS 1)in diethylnitrosamine-(DEN)-inducedenzyme-altered liver cells were studied by means of immunohistochemical(PAP)and in situcDNA-mRNA hybridization methods.The experi... The changes of carbamyl phosphate synthetase I(CPS 1)in diethylnitrosamine-(DEN)-inducedenzyme-altered liver cells were studied by means of immunohistochemical(PAP)and in situcDNA-mRNA hybridization methods.The experimental rats were treated with DEN,2-acetylaminofluorene(2-AAF)and 2/3 hepatectomy according to Solt-Farber’s protocol andwere further promoted by oral daily administration of 0.05% phenobarbital in drinking water.The results showed that the average number of lesions showing abnormal expression of CPS1 was relatively constant over the course of the experiment(8 months),while the numberof normally expressing lesions gradually decreased.The former lesions were also largerin volume than the latter ones.We conclude that in DEN-initiated lesions the abnormallyexpressed CPS 1 lesions may grow continuously,thus leading to the formation of largernodules.We also suspect that some of these lesions have increased tendencies to developinto tumors. 展开更多
关键词 carbamyl phosphate SYNTHETASE I DIETHYLNITROSAMINE HEPATOCARCINOGENESIS in situ hybridization IMMUNOHISTOCHEMISTRY
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