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Derivative Spectroscopy and its Application at Detecting the Weak Emission/Absorption Lines
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作者 Lihuan Yu Jiangdan Li +4 位作者 Jinliang Wang Jiajia Li Jiao Li Qiang Xi Zhanwen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期205-223,共19页
The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened ... The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened up unprecedented opportunities for stellar classification.Specific types of stars,such as early-type emission-line stars and those with stellar winds,can be distinguished by the profiles of their spectral lines.In this paper,we introduce a method based on derivative spectroscopy(DS)designed to detect signals within complex backgrounds and provide a preliminary estimation of curve profiles.This method exhibits a unique advantage in identifying weak signals and unusual spectral line profiles when compared to other popular line detection methods.We validated our approach using synthesis spectra,demonstrating that DS can detect emission signals three times fainter than Gaussian fitting.Furthermore,we applied our method to 579,680 co-added spectra from LAMOST Medium-Resolution Spectroscopic Survey,identifying 16,629 spectra with emission peaks around the Hαline from 10,963 stars.These spectra were classified into three distinct morphological groups,resulting in nine subclasses as follows.(1)Emission peak above the pseudo-continuum line(single peak,double peaks,emission peak situated within an absorption line,P Cygni profile,Inverse P Cygni profile);(2)Emission peak below the pseudo-continuum line(sharp emission peak,double absorption peaks,emission peak shifted to one side of the absorption line);(3)Emission peak between the pseudo-continuum line. 展开更多
关键词 line identification-line profiles-methods data analysis-techniques spectroscopic-techniques radial velocities
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Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines
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作者 Justus Thomas Obiajulu Sievers Anom Bowolaksono R.Tedjo Sasmono 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第5期215-224,共10页
Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,J... Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PCR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.Conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery. 展开更多
关键词 Zika virus Infectivity REPLICATION Cell lines In vitro
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GATA binding protein 2 mediated ankyrin repeat domain containing 26 high expression in myeloid-derived cell lines
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作者 Yang-Zhou Jiang Lan-Yue Hu +11 位作者 Mao-Shan Chen Xiao-Jie Wang Cheng-Ning Tan Pei-Pei Xue Teng Yu Xiao-Yan He Li-Xin Xiang Yan-Ni Xiao Xiao-Liang Li Qian Ran Zhong-Jun Li Li Chen 《World Journal of Stem Cells》 SCIE 2024年第5期538-550,共13页
BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untran... BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and extracellular signal regulated kinase 1/2 signaling pathways,which are potentially involved in the regulation of thrombopoietin-dependent signaling and further impair proplatelet formation by megakaryocytes(MKs)[11].However,the positive regulators of ANKRD26,which might be associated with THC2 pathology,are still unknown. 展开更多
关键词 Ankyrin repeat domain containing 26 GATA binding protein 2 Thrombocytopenia 2 Transcriptional regulation Myeloid-derived cell lines
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Study on the Design Scheme of Vehicle Flow Lines in Unilateral Agglomerative Open Service Area
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作者 Tengfei Gong 《Journal of World Architecture》 2024年第3期22-29,共8页
In recent years,with the introduction of the strategy to strengthen the country’s transportation infrastructure and the continuous implementation of new economic development models such as integrating transportation ... In recent years,with the introduction of the strategy to strengthen the country’s transportation infrastructure and the continuous implementation of new economic development models such as integrating transportation with tourism,various open service areas integrating highway service areas with local tourism have emerged nationwide.Examples include the Yangcheng Lake service area in Jiangsu and the Lengshui service area in Chongqing.This paper focuses on the design example of the Dazu Stone Carving service area on the Chongqing section of the Yurong Expressway,comprehensively considering factors such as construction scale,terrain conditions,and local urban planning.It analyzes and studies the traffic flow design of unilateral agglomerative open service areas around two vehicle traffic conversion links:between the main expressway and the service area,and between the service area and local roads.The aim is to provide a case study reference for similar projects. 展开更多
关键词 Unilateral agglomeration Open service area Traffic flow line Online publication:July 11 2024
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Molecular cytogenetic analyses of two new wheat-rye 6RL translocation lines with resistance to wheat powdery mildew 被引量:1
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作者 Shanying Zhu Haonan Du +9 位作者 Fuyu Su Jin Wang Qingfeng Meng Tianlei Liu Rui Guo Zhaozhao Chen Huanhuan Li Wenxuan Liu Pengtao Ma Huagang He 《The Crop Journal》 SCIE CSCD 2023年第2期584-592,共9页
Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye ... Rye(Secale cereale)is a valuable gene donor for wheat improvement,especially for its resistance to diseases.Developing rye-derived resistance sources is important for wheat breeding.In the present study,two wheat-rye derivatives,designated JS016 and JS110,were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A.Using sequential genomic in situ hybridization(GISH)and multicolor fluorescence in situ hybridization(mc-FISH),JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line,respectively.Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation.The wheat 55K single-nucleotide polymorphism(SNP)array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110,respectively.Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s)that was derived from the 6RL translocation but differed from Pm20.Moreover,JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20.To efficiently transfer and detect the 6RL translocation from JS016 and JS110,one 6RL-specific Kompetitive allele specific PCR(KASP)marker was developed and validated in high throughput marker-assisted selection(MAS). 展开更多
关键词 Secale cereale Translocation line Wheat powdery mildew GISH/FISH KASP marker
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Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe 被引量:1
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作者 WEI Wen-bin YUAN Lin +1 位作者 ZHOU Jia-sheng LIU Zheng 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期221-232,共12页
Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which cau... Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole line.In this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical methods.Two types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,respectively.The hydraulic expansion and bending experiments of small-scale MLPs are conducted.In addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive side.In contrast,the liner of ALP remains intact without developing any wrinkling and collapse mode.In addition,a dedicated numerical framework and theoretical models were also established.It was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results. 展开更多
关键词 lined pipe BENDING nonlinear ring theory BUCKLING PLASTICITY
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Fertility,genome stability,and homozygosity in a diverse set of resynthesized rapeseed lines
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作者 Elizabeth Ihien Katche Antje Schierholt +2 位作者 Heiko C.Becker Jacqueline Batley Annaliese S.Mason 《The Crop Journal》 SCIE CSCD 2023年第2期468-477,共10页
Rapeseed(Brassica napus,AACC)was formed by hybridization between progenitor species Brassica rapa(AA)and Brassica oleracea(CC).As a result of a limited number of hybridization events between specific progenitor genoty... Rapeseed(Brassica napus,AACC)was formed by hybridization between progenitor species Brassica rapa(AA)and Brassica oleracea(CC).As a result of a limited number of hybridization events between specific progenitor genotypes and strong breeding selection for oil quality traits,rapeseed has limited genetic diversity.The production of resynthesized B.napus lines via interspecific hybridization of the diploid progenitor species B.rapa and B.oleracea is one possible way to increase genetic variation in rapeseed.However,most resynthesized lines produced so far have been reported to be meiotically unstable and infertile,in contrast to established B.napus cultivars.This hinders both maintenance and use of this germplasm in breeding programs.We characterized a large set of 140 resynthesized lines produced by crosses between B.rapa and B.oleracea,as well as between B.rapa and wild C genome species(B.incana,B.hilarionis,B.montana,B.Bourgeaui,B.villosa and B.cretica)for purity(homozygosity),fertility,and genome stability.Self-pollinated seed set,seeds per ten pods as well as percentage pollen viability were used to estimate fertility.SNP genotyping was performed using the Illumina Infinium Brassica 60K array for 116 genotypes,with at least three individuals per line.Most of the material which had been advanced through multiple generations was no longer pure,with heterozygosity detected corresponding to unknown parental contributions via outcrossing.Fertility and genome stability were both genotypedependent.Most lines had high numbers of copy number variants(CNVs),indicative of meiotic instability,and high numbers of CNVs were significantly associated with reduced fertility.Eight putatively stable resynthesized B.napus lines were observed.Further investigation of these lines may reveal the mechanisms underlying this effect.Our results suggest that selection of stable resynthesized lines for breeding purposes is possible. 展开更多
关键词 FERTILITY Genome stability Copy number variants SNP genotyping Resynthesized lines
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Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity Transmission Lines
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作者 Ounyesiga Living Stephen Ndubuisi Nnamchi +2 位作者 Kelechi John Ukagwu Abubakar Abdulkarim Zaid Oluwadurotimi Jagun 《Energy and Power Engineering》 CAS 2023年第2期127-150,共24页
The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques... The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages. 展开更多
关键词 MINIMIZATION Power Losses Transmission lines Corona and Ohms Losses Transmission Model
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A SCREW DISLOCATION IN A THREE-PHASE COMPOSITE CYLINDER MODEL WITH INTERFACIAL RIGID LINES 被引量:2
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作者 Fang Qihong Liu Youwen Jiang Chiping 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第4期283-294,共12页
The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex mul... The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex multiply connected region is developed, with which explicit series form solutions of the complex potentials in the matrix, and the interphase layer and inclusion regions are derived. Based on the complex potentials, the image force on the screw dislocation is then calculated by using the Peach-Koehler formula. The equilibrium position of the dislocation is discussed in detail for various rigid line geometries, interphase layer thicknesses and material property combinations. The main results show that the interracial rigid lines exert a significant perturbation effect on the motion of the screw dislocation near the circular inclusion surrounded by an interphase layer. 展开更多
关键词 screw dislocation interfacial rigid lines interphase layer complex potential method image force
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Construction of EMS-Induced Peanut Mutant Libraries and Identification of Pod-Related Traits Mutant Lines
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作者 Hao Chen Faqian Xiong +9 位作者 Rilong Xu Xiangyu Chen Haifeng Zhong Yumei Zhang Xinlong Lan Hong Zhang Yuhua Chen Runfang Hu Guoqiang Lin Zhaoxiu Tang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第2期537-557,共21页
Peanut(Arachis hypogaea L.)is an oil and economic crop of vital importance,and peanut pod is the key organ influencing the yield and processing quality.Hence,the Pod-related traits(PRTs)are considered as important agr... Peanut(Arachis hypogaea L.)is an oil and economic crop of vital importance,and peanut pod is the key organ influencing the yield and processing quality.Hence,the Pod-related traits(PRTs)are considered as important agronomic traits in peanut breeding.To broaden the variability of PRTs in current peanut germplasms,three elite peanut cultivars were used to construct Ethyl methane sulfonate(EMS)-induced mutant libraries in this study.The optimal EMS treatment conditions for the three peanut varieties were determined.It was found that the median lethal dose(LD50)of EMS treatment varied greatly among different genotypes.Finally,the EMS-induced peanut mutant libraries were constructed and a total of 124 mutant lines for PRTs were identified and evaluated.Furthermore,“M-8070”,one of the mutant lines for pod constriction,was re-sequenced via high-throughput sequencing technology.The genome-wide variations between“M-8070”and its wild parent“Fuhua 8”(FH 8)were detected.2994 EMS-induced single nucleotide polymorphisms(SNPs)and 1188 insertion-deletions(InDels)between“M-8070”and its wild parent were identified.The predominant SNP mutation type was C/G to T/A transitions,while the predominant InDel mutation type was“1-bp”.We analyzed the distribution of identified mutations and annotated their functions.Most of the mutations(91.68%of the SNPs and 77.69%of the InDels)were located in the intergenic region.72 SNPs were identified in the exonic region,leading to 27 synonymous,43 nonsynonymous and 2 stop-gain variation for gene structure.13 Indels were identified in the exonic region,leading to 4 frame-shift,8 non-frame-shift and 1 stop-gain variations of genes.These mutations may lead to the phenotypic variation of“M-8070”.Our study provided valuable resources for peanut improvement and functional genomic research. 展开更多
关键词 PEANUT EMS-induced mutant line pod-related traits RE-SEQUENCING pod constriction
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Multi-Equipment Detection Method for Distribution Lines Based on Improved YOLOx-s
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作者 Lei Hu Yuanwen Lu +2 位作者 Si Wang Wenbin Wang Yongmei Zhang 《Computers, Materials & Continua》 SCIE EI 2023年第12期2735-2749,共15页
The YOLOx-s network does not sufficiently meet the accuracy demand of equipment detection in the autonomous inspection of distribution lines by Unmanned Aerial Vehicle(UAV)due to the complex background of distribution... The YOLOx-s network does not sufficiently meet the accuracy demand of equipment detection in the autonomous inspection of distribution lines by Unmanned Aerial Vehicle(UAV)due to the complex background of distribution lines,variable morphology of equipment,and large differences in equipment sizes.Therefore,aiming at the difficult detection of power equipment in UAV inspection images,we propose a multi-equipment detection method for inspection of distribution lines based on the YOLOx-s.Based on the YOLOx-s network,we make the following improvements:1)The Receptive Field Block(RFB)module is added after the shallow feature layer of the backbone network to expand the receptive field of the network.2)The Coordinate Attention(CA)module is added to obtain the spatial direction information of the targets and improve the accuracy of target localization.3)After the first fusion of features in the Path Aggregation Network(PANet),the Adaptively Spatial Feature Fusion(ASFF)module is added to achieve efficient re-fusion of multi-scale deep and shallow feature maps by assigning adaptive weight parameters to features at different scales.4)The loss function Binary Cross Entropy(BCE)Loss in YOLOx-s is replaced by Focal Loss to alleviate the difficulty of network convergence caused by the imbalance between positive and negative samples of small-sized targets.The experiments take a private dataset consisting of four types of power equipment:Transformers,Isolators,Drop Fuses,and Lightning Arrestors.On average,the mean Average Precision(mAP)of the proposed method can reach 93.64%,an increase of 3.27%.The experimental results show that the proposed method can better identify multiple types of power equipment of different scales at the same time,which helps to improve the intelligence of UAV autonomous inspection in distribution lines. 展开更多
关键词 Distribution lines UAV autonomous inspection power equipment detection YOLOx-s
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Saturated absorption spectrum of cesium micrometric-thin cell with suppressed crossover spectral lines
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作者 韩俊龙 王博闻 +5 位作者 郑俊鹤 陈书源 肖伟 吴腾 郭弘 彭翔 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期353-360,共8页
Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimental... Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimentally study the saturated absorption spectra using a 100-μm cesium MC,where the pump and probe beams are linearly polarized with mutually perpendicular polarizations,and the magnetic field is along the pump beam.Because of the distinctive thin chamber of the MC,crossover spectral lines in saturated absorption spectra are largely suppressed leading to clear splittings of hyperfine Zeeman transitions in experiments,and the effect of spatial magnetic field gradient is expected to be reduced.A calculation method is proposed to achieve good agreements between theoretical calculations and experimental results.This method successfully explains the suppression of crossover lines in MCs,as well as the effects of magnetic field direction,propagation and polarization directions of the pump/probe beam on saturated absorption spectrum.The saturated absorption spectrum with suppressed crossover lines is used for laser frequency stabilization,which may provide the potential value of MCs for high spatial resolution strong-field magnetometry with high sensitivity. 展开更多
关键词 micrometric-thin cells saturated absorption spectrum hyperfine Zeeman splitting crossover spectral lines laser frequency stabilization
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Data-Centric Approach to Digital Twin Modeling of Production Lines
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作者 丁永效 李纪奇 +2 位作者 刘国华 倪萍 吴金发 《Journal of Donghua University(English Edition)》 CAS 2023年第4期397-403,共7页
Digital twin(DT) is a virtual replica of a physical world that has become one of the most important ideas in the manufacturing industry’s digital revolution. DT modeling is a vital issue in building a DT of a product... Digital twin(DT) is a virtual replica of a physical world that has become one of the most important ideas in the manufacturing industry’s digital revolution. DT modeling is a vital issue in building a DT of a production line. In this paper, a method is proposed to address the difficulties of complicated production line business and data heterogeneity. The method focuses on essential data in the production line and creates conceptual and information models based on the ArtiFlow model and AutomationML(AML). Conceptual models are mainly used to describe and analyze the business activities of the production line, and information models describe real production lines in the form of XML files. The proposed modeling approach has been applied to a real-world clothing production line to demonstrate its feasibility and effectiveness. 展开更多
关键词 digital twin(DT) ArtiFlow production line AutomationML(AML)
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STUDY ON THREE-DIMENSIONAL FINITE BODIES CONTAINING CRACKS USING THE FINITE ELEMENT METHOD OF LINES 被引量:2
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作者 HuShaowei WangHongxia 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期83-94,共12页
The three-dimensional finite element method of lines is presented, and the basic processing description of 3D FEMOL in cracking questions is given in detail. Applications to 3D bodies with cracks indicate that good ac... The three-dimensional finite element method of lines is presented, and the basic processing description of 3D FEMOL in cracking questions is given in detail. Applications to 3D bodies with cracks indicate that good accuracy can be obtained with relatively coarse girds. In particular, application to the tension specimen shows very good agreement with the evaluation of stress intensity factors, which is better than the results of other methods. This implies a considerable potential for using this method in the 3D analysis of finite geometry solids and suggests a possible extension of this technique to nonlinear material behavior. 展开更多
关键词 3D finite element method of lines. 3D bodies with cracks stress intensity factors
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N^(6)-腺苷甲基化修饰及其对LINE-1的调控机制
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作者 张傲 岑山 李晓宇 《遗传》 CAS CSCD 北大核心 2024年第3期209-218,共10页
长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细... 长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细胞对其进行相关修饰直接影响转座。N^(6)-腺苷甲基化修饰(m^(6)A)是真核细胞RNA上最丰富且动态可逆的表观遗传修饰。目前发现m^(6)A修饰也存在于LINE-1 mRNA上,参与LINE-1整个生命周期的调控,影响其转座和基因组中LINE-1相邻基因的表达,进而影响基因组稳定性、细胞自我更新与分化潜能,在人类发育和疾病中具有重要作用。本文介绍了LINE-1 m^(6)A修饰的位置、功能以及相关机制,并总结了LINE-1的m^(6)A修饰对其转座调控的研究进展,以期为相关疾病发生发展的机制研究和治疗提供新的思路。 展开更多
关键词 m^(6)A修饰 逆转录转座子 line-1 基因组 基因组稳定性
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Crossing Limit Cycles of Planar Piecewise Hamiltonian Systems with Linear Centers Separated by Two Parallel Straight Lines
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作者 Zhou Jin 《Journal of Applied Mathematics and Physics》 2023年第5期1429-1447,共19页
In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of... In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of systems with a center in two zones and without equilibrium points in the other zone (or with a center in one zone and without equilibrium points in the other zones). In addition, we also give examples to illustrate that it can reach the maximal number. 展开更多
关键词 Limit Cycles Planar Piecewise Hamiltonian Systems Straight lines CENTERS Equilibrium Points
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AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE THREE-DIMENSIONAL FLOW IN CASCADES;PART I—TOPOLOGICAL RULES FOR SKIN-FRICTION LINES AND SECTION STREAMLINES 被引量:2
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作者 康顺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第5期489-495,共7页
Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rul... Based on the working of Lighthill and Hunt et al., in the present paper the author has established the topological rules adapting to analysing the skin-friction lines and the section streamlines in cascades. These rules are (1) for a rotor cascade without shroud band, the total number of nodal points equals that the saddle points on the skin-friction line vector fields in eachpitch range; (2) for an annular or straight cascade with no-clearances at blade ends, the total number of saddle points is two more than that of nodal points on the skin-friction line fields in a pitch; (3) the total number of saddles in the secondary flow fields on cross-sections in cascade is one less than that of nodes; (4) in the section streamline vector fields on a meridian surface penetrating a flow passage, and on leading and trailing edge sections, the total number of nodes is equal to that of saddles; (5) on the streamline vector fields of a blade-to-blade surface, the total number of nodes is one less than that of saddles. 展开更多
关键词 node TOPOLOGICAL RULES FOR SKIN-FRICTION lines AND SECTION STREAMlines AN APPLICATION OF TOPOLOGICAL ANALYSIS TO STUDYING THE three-DIMENSIONAL FLOW IN CASCADES PART I
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低压低氧对肠黏膜屏障及LINE-1核酸内切酶变异体GCRG213表达的影响
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作者 张王静怡 张少杰 +4 位作者 陶虹锦 孟繁森 刘静 朱玲玲 王刚石 《解放军医学院学报》 CAS 2024年第3期296-301,F0003,共7页
背景长散在核元件-1(long interspersed nuclear element-1,LINE-1或L1)是目前基因组中唯一活跃的自主反转录转座元件,低压低氧环境可以改变L1的甲基化程度。目的探究低压低氧环境对肠黏膜中L1核酸内切酶(L1 endonuclease,L1-EN)变异体G... 背景长散在核元件-1(long interspersed nuclear element-1,LINE-1或L1)是目前基因组中唯一活跃的自主反转录转座元件,低压低氧环境可以改变L1的甲基化程度。目的探究低压低氧环境对肠黏膜中L1核酸内切酶(L1 endonuclease,L1-EN)变异体GCRG213表达水平及以闭合蛋白(Occludin)和紧密连接蛋白-1(Claudin-1)表达水平为指标的肠黏膜机械屏障功能的影响。方法利用免疫组织化学染色(immunohistochemical staining,IHC)检测人正常小肠、结肠组织及小鼠正常结肠组织的GCRG213表达,观察GCRG213蛋白在正常肠道中的分布规律。将雄性C57BL/6小鼠随机分为实验组和对照组。实验组模拟海拔6000 m环境,饲养7 d构建低压低氧小鼠模型,对照组常压常氧饲养。将人正常结肠上皮细胞NCM-460随机分为常氧组以及低氧24 h、48 h组,常氧组于常氧环境正常培养,低氧组分别于0.3%O2浓度下培养24 h、48 h构建低氧细胞模型。使用qPCR、Western blot技术检测GCRG213、Occludin和Claudin-1在小鼠结肠组织及人NCM-460细胞中表达水平的变化。结果人正常小肠、结肠及小鼠结肠组织IHC结果一致显示,GCRG213表达于肠黏膜柱状上皮细胞胞质中,而在杯状细胞中未见表达。在动物实验中,与常氧组相比,低压低氧组小鼠结肠组织GCRG213在mRNA水平(P<0.05)和蛋白水平(P<0.01)均表达上调;同时,Occludin在蛋白水平表达下调(P<0.05)。在细胞实验中,低氧暴露后NCM-460细胞中GCRG213在mRNA(P<0.001)和蛋白水平(P<0.01)均表达上调,其中低氧24 h组GCRG213表达水平低于低氧48 h组,Occludin、Claudin-1在mRNA水平(P<0.01;P<0.001)表达下调,其中低氧24 h组表达水平均低于低氧48 h组,Occludin蛋白水平表达在低氧48 h组出现下调(P<0.05)。结论L1-EN变异体GCRG213在人和小鼠正常结肠组织黏膜柱状上皮细胞胞质内存在表达;在体内外模型中,低压低氧暴露下结肠黏膜上皮细胞GCRG213表达升高,同时观察到低压低氧对结肠黏膜紧密连接完整性产生影响,表现为Occludin、Claudin-1蛋白表达水平的降低。 展开更多
关键词 低压低氧 肠黏膜 紧密连接蛋白 GCRG213 line-1
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A Miniaturized Broadband Wilkinson Power Divider Using Micro-Strip Branch Lines
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作者 Taifu Zhou 《Journal of Computer and Communications》 2023年第12期102-108,共7页
A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stag... A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stage Wilkinson power dividers. To demonstrate its performance, an improved single-stage Wilkinson power divider with four micro-strip branch lines was designed. Simulated results show that the insert loss is better than 3.2 dB, the input return loss, output return loss, and isolation are better than 15 dB respectively, across a 76% bandwidth from 18 to 40 GHz. . 展开更多
关键词 BROADBAND Micro-Strip Branch lines Power Divider
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Analysis and Simulation of the Influence of Electromagnetic Fields on Living Beings near HV Power Lines Using the FDTD Method
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作者 Anthony Bassesuka Sandoka Nzao 《Open Journal of Applied Sciences》 2023年第12期2343-2359,共17页
Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-freque... Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-frequency electromagnetic fields on the environment and which are capable of modifying and destroying our ecosystem. Particular interest was given in this article due to a massive influx of population living near high voltage lines. The analysis and simulation of the influence of low frequency electromagnetic fields on living beings in the vicinity of high voltage sources 132 kV and 220 kV in urban areas in DR Congo is the subject of our research with a view to estimating the level of exposure of humans to low frequency electromagnetic fields. To carry out our research, we used the classic method of analyzing the field produced near a high voltage line based on Maxwell’s image theory, the Maxwell-Gauss theorem and Maxwell-Ampère theorem to model and quantify low-frequency electromagnetic fields in the vicinity of high-voltage lines. The 2D FDTD numerical formulation was developed from telegraphers’ equations and allowed us to obtain models of current and voltage induced by electromagnetic fields on living beings below and near HV lines. The different simulations carried out on the proposed models illustrate the effects of the electrical and geometric parameters of the pylons on the distribution of the electromagnetic field in the vicinity of the HV lines. The results obtained were compared to the safety limits recommended by the standards. 展开更多
关键词 Low Frequency Electromagnetic Field Modeling Field and Health Maxwell’s Equations FDTD Method Electromagnetic Compatibility High Voltage line
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