检索结果-南通市图书馆

Genetic and Epigenetic Understanding of the Seasonal Timing of Flowering

在线全文

学校读者我要写书评

暂无评论

Plant Communications 2020年第1期1卷 25-37页

作者： Yuehui He tao Chen Xiaolin zeng National Key Laboratory of Plant Molecular Genetics&Shanghai Center for Plant Stress Biology Chinese Academy of Sciences Center for Excellence in Molecular Plant SciencesShanghai 201602China

The developmental transition to flowering in many plants is timed by changing seasons,which enables plants to flower at a season that is favorable for seed *** plants grown at high latitudes perceive the seasonal cues of changing day length and/or winter cold(prolonged cold exposure),to regulate the expression of flowering-regulatory genes through the photoperiod pathway and/or vernalization pathway,and thus align flowering with a particular *** studies in the model flowering plant Arabidopsis thaliana have revealed that diverse transcription factors engage various chromatin modifiers to regulate several key flowering-regulatory genes including FLOWERING LOCUS C(FLC)and FLOWERING LOCUS T(FT)in response to seasonal ***,we summarize the current understanding of molecular and chromatin-regulatory or epigenetic mechanisms underlying the vernalization response and photoperiodic control of flowering in ***,the conservation and divergence of regulatory mechanisms for seasonal flowering in crops and other plants are briefly discussed.

关键词： vernalization photoperiodism flowering time FLOWERING LOCUS C FLOWERING LOCUS T chromatin modification

Effect of plastic strain and forming temperature on magnetic properties of low-carbon steel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 210-219页

作者： Fan zeng Xue-jiao Bai Cheng-liang Hu Min-jun Tang Zhen Zhao Institute of Forming Technology and Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200030China National Engineering Research Center of Die&Mold CAD Shanghai Jiao Tong UniversityShanghai 200030China Jiangsu Longcheng Precision Forging Co. Ltd.Changzhou 213000China

Claw poles are a key component of automobile *** output power performance of the generator is very dependent on the magnetic properties of its claw *** deformation is known to significantly change the magnetic behavior of ferromagnetic materials in claw *** this paper,changes in the magnetic properties of low-carbon steel,used for claw pole components due to their plastic deformation,were investigated for different strains and ***-shaped material samples were prepared by machining and their magnetic properties were *** surface roughness was first evaluated and a machining process with an arithmetic average of roughness Ra 1.6μm was selected as enabling the lowest measurement *** loops at different applied magnetic fields of the material were obtained for different plastic strains and forming *** magnetic parameters of magnetic flux density,coercivity,and remanence were obtained and compared with magnetic flux density as the primary *** showed that machining,cold forming,and hot forming all led to lower magnetic flux density,larger coercivity,and smaller *** flux density showed a sharp decrease at the start of plastic deformation,but as the strain increased,the decreasing trend gradually reached a constant *** decrease was much larger for cold forming than for hot *** example,at 500 A/m,the degradation of magnetic flux density with a reduction percentage of 5%at room temperature was about 50%,while that of hot forming at 1200°C was about 10%.Results of this research may provide a reference for the future process design of hot-forged claw poles.

关键词： low-carbon steel magnetic properties hot forming cold forming surface roughness

Two-Stage Lesion Detection Approach Based on Dimension-Decomposition and 3D Context

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2022年第1期27卷 103-113页

作者： Jiacheng jiao Haiwei Pan Chunling Chen tao Jin Yang Dong Jingyi Chen the College of Computer Science and Technology Harbin Engineering UniversityHarbin 150001China the School of Software Tsinghua UniversityBeijng 100084China

Lesion detection in Computed Tomography(CT) images is a challenging task in the field of computer-aided *** important issue is to locate the area of lesion *** a branch of Convolutional Neural Networks(CNNs),3D Context-Enhanced(3DCE) frameworks are designed to detect lesions on CT *** False Positives(FPs) detected in 3DCE frameworks are usually caused by inaccurate region proposals,which slow down the inference *** solve the above problems,a new method is proposed,a dimension-decomposition region proposal network is integrated into 3DCE framework to improve the location accuracy in lesion *** the restriction of "anchors" on ratios and scales,anchors are decomposed to independent "anchor strings".Anchor segments are dynamically combined in accordance with probability,and anchor strings with different lengths dynamically compose bounding *** show that the accurate region proposals generated by our model promote the sensitivity of FPs and spend less inference time compared with the current methods.

关键词： lesion detection Computed Tomography(CT) dimension-decomposition 3D context computer-aided diagnosis

Solving Time Dependent Fokker-Planck Equations via Temporal Normalizing Flow

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2022年第7期32卷 401-423页

作者： Xiaodong Feng Li zeng tao Zhou LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAMSSChinese Academy of SciencesBeijingChina

In this work,we propose an adaptive learning approach based on temporal normalizing flows for solving time-dependent Fokker-Planck(TFP)*** is well known that solutions of such equations are probability density functions,and thus our approach relies on modelling the target solutions with the temporal normalizing *** temporal normalizing flow is then trained based on the TFP loss function,without requiring any labeled *** a machine learning scheme,the proposed approach is mesh-free and can be easily applied to high dimensional *** present a variety of test problems to show the effectiveness of the learning approach.

关键词： Temporal normalizing flow Fokker-Planck equations adaptive density approximation

Shape and Size Optimization of Truss Structures under Frequency Constraints Based on Hybrid Sine Cosine Firefly Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2023年第1期134卷 405-428页

作者： Ran tao Xiaomeng Yang Huanlin Zhou zeng Meng School of Civil Engineering Hefei University of TechnologyHefei230009China

Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local ***,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element *** full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence ***,the population is classified,and different populations are updated by modified FA and SCA ***,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population *** selection technique is applied to save the promising solutions and further improve the convergence ***,the adaptive penalty function is employed to deal with the ***,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency *** results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints.

关键词： Firefly algorithm sine cosine algorithm frequency constraints structural optimization

Rifampicin inhibits apoptosis in rotenone-induced differentiated PC12 cells by ameliorating mitochondrial oxidative stress

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2010年第4期5卷 251-256页

作者： Shiwen Chen Yuanlin Sun Zhifeng zeng Enxiang tao Department of Neurology Second Affiliated Hospital Sun Yat-Sen University Guangzhou 510120 Guangdong Province China

BACKGROUND： Previous studies have shown that rifampicin exhibits neuroprotective effects, but the precise mechanisms remain unclear. Rifampicin is thought to exert the neuroprotective effect as a hydroxyl free radical scavenger. OBJECTIVE： To investigate the protective effects of rifampicin pretreatment on rotenone-induced mitochondrial oxidative stress in differentiated PC12 ***, TIME AND SETrlNG： A repeated measure, cell-based study was performed at the Department of Neurology, Second Affiliated Hospital, Sun Yat-sen University, China between December 2007 and November 2008. MATERIALS： PC12 cells were a kind gift from the Physiology Laboratory of Zhongshan Medical School, Sun Yat-sen University, China. Rotenone and rifampicin were purchased from Sigma, USA. METHODS： PC12 cells were differentiated by culturing with 100 ng/mL 7S nerve growth factor for 9 days in Dulbecco＇s modified Eagle＇s medium/Nutrient Mix F12 （DMEM/F12） supplemented with 10% fetal bovine serum. The cells were assigned to six groups according to various treatment conditions： control, cultured with normal media; rifampicin group, treated with 300 pmol/L rotenone for 26 hours; rotenone group, treated with 2.5 pmol/L rotenone for 24 hours; rifampicin pretreatment groups, pretreated with 100, 200, and 300 pmol/L rifampicin for 2 hours, respectively, followed by 2.5 μmol/L rotenone for 24 *** OUTCOME MEASURES： Mitochondrial membrane potential was measured by fluorescence microscopy and flow cytometry, respectively, using rhodamine123 staining. Intracellular reactive oxygen species formation was analyzed by flow cytometry using 2＇, 7＇-dichlorofluorescin-diacetate staining, and intracellular reduced glutathione was measured with a microplate reader. Cell viability was determined by 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide assay. Cell apoptosis was detected by Hoechst 33342 staining and flow cytometry. RESULTS： Increased apoptosis in rotenone-induced, differentiated,

关键词： rifampicin rotenone PC12 cells mitochondrial dysfunction oxidative stress apoptosis neural regeneration

Effect of Precipitation on Intergranular Corrosion Resistance of 430 Ferritic Stainless Steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2015年第11期22卷 1062-1068页

作者： Xun-zeng HUANG Dan WANG Yi-tao YANG School of Materials Science and Engineering Shanghai University

With Nb-Ti-stabilized 430 ferritic stainless steel（NTS430FSS） and SUS 430 ferritic stainless steel（SUS430FSS） as experimental materials, the influence of precipitation on intergranular corrosion resistance was investigated. A series of aging treatment were carried out. The free-exposure corrosion test and double loop electrochemical potentiokinetic reactivation（DL-EPR） test with a scan rate of 1.67 m V/s at 26 °C were applied to evaluate the intergranular corrosion（IGC） resistance. Metallographic observation, scanning electron microscope（SEM）, transmission electron microscope（TEM） with energy dispersive spectroscopy（EDS） and X-ray diffraction（XRD） analysis were conducted. The results show that IGC occurred in SUS430 FSS aged above 700 °C, while it occurred in NTS430 FSS as the temperature was improved to 1 050 °C. The critical degree of sensitization Ir/Ia reaches 0.305 in SUS430 FSS, which is higher than that of NTS430 FSS, i.e. 0.010, aged at 950 °C for 2 h. The TEM, EDS and XRD results show that a large amount of Cr23C6 precipitates with size of 60 nm×22 nm are located at the SUS430 FSS grain boundaries as chains. With the addition of Nb and Ti and reduction of C, the amount of precipitates reduces significantly in NTS430 FSS. A majority of Cr23C6 were replaced by Ti C and Nb C. Only a small amount of spherical Ti C（R=186 nm） and square Ti N（312 nm×192 nm） with Nb and Cr adsorbed are left along grain boundaries. Due to the dual stabilization of Nb and Ti, the precipitation of Cr23C6 is restrained, the chromium depleted region is avoided and accordingly the resistance to the intergranular corrosion is improved.

关键词： 430 ferritic stainless steel intergranular corrosion double-loop electrochemical potentiokinetic reactivation carbonitride extraction precipitation

Effect of three insect-resistant maizes expressing Cry1le,Cry1Ab/Cry2Aj and Cry1Ab on the growth and development of armyworm Mythimna separata(Walker)

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2020年第7期19卷 1842-1849页

作者： SU Hong-hua JIANG tao SUN Yu GU Hui-jie WU jiao-jiao YANG Yi-zhong School of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009P.R.China

Three transgenic maize events(IE09S034,Shuangkang 12--5 and C0030.3.5)produced Cry1le,Cry1Ab/Cry2Aj and G10-EPSPS,Cry1Ab and EPSPS,respectively,all of which target the Asian corn *** oriental armyworm Mythimna separata(Walker)is the secondary *** this study,the effects of the three Bt maizes on the development and survival of armyworm were *** results showed that IE09S034 had insecticidal activity against 1st instar larvae,and the survival rate of armyworm fed with Bt maize for 10 days was 462%,significantly lower than that of the *** larvae at 3rd--6th instar were more tolerant of the Bt toxin than the early instar ***,Shuangkang 12-5 had good insecticidal activity against 1st-5th instar *** mortality was nearly 100%when the larvae were fed with Shuangkang 12-5 before 3rd instar,and the toxin had quick acting *** event significantly ihibited the development of armyworm;that is,the larval duration of the 3rd and 4th instar larvae fed with Shuangkang 12-5 was prolonged by 4.5 and 3.0 days,*** pupal weight and egg number were also significantly lower than those of the *** C0030.3.5,it could control 1st--5th instar larvae *** mortality rates were all over 50%if 1st-3rd larvae were fed with this *** pupal weight of 4th-6th instar larvae fed with Bt maize were only 53.9,56.8 and 54.6%,respectively,compared to that of the *** number of eggs laid was significantly less than the *** results indicate that all three transgenic maize events exhibit the potential to provide effective control of early instar larvae of *** can be commercialized in future to control lepidoptera pests such as Asian corn borer and armyworm.

关键词： transgenic maize armyworm development survival

Diagnosing phenotypes of single-sample individuals by edge biomarkers

在线全文

学校读者我要写书评

暂无评论

Journal of Molecular Cell Biology 2015年第3期7卷 231-241页

作者： Wanwei Zhang tao zeng Xiaoping Liu Luonan Chen Key Laboratory of Systems Biology Innovation Center for Cell Signaling NetworkInstitute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

Network or edge biomarkers area reliable form to characterize phenotypes or ***,obtaining edges orcorrelations between molecules for an individual requires measurement ofmultiple samples of that individual,which are generally unavailable in clinical ***,it is strongly demanded to diagnose a disease by edge or network biomarkers in one-sample-for-one-individual ***,we developed a new computational framework,EdgeBiomarker,to integrate edge and node biomarkers to diagnose phenotype of each single test *** applying the method to datasets of lung and breast cancer,it reveals new marker genes/gene-pairs and related sub-networks for distinguishing earlier and advanced cancer *** method shows advantages over traditional methods:(i)edge biomarkers extracted from non-differentially expressed genes achieve better cross-validation accuracy of diagnosis than molecule or node biomarkers from differentially expressed genes,suggesting that certain pathogenic information is only present at the level of network and under-estimated by traditional methods;(ii)edge biomarkers categorize patients into low/high survival rate in a more reliablemanner;(iii)edge biomarkers are significantly enriched in relevant biological functions or pathways,implying that the association changes ina network,rather than expression changes in individual molecules,tendtobe causally related to cancer *** new frameworkof edgebiomarkers paves theway for diagnosing diseases and analyzing the irmolecular mechanisms by edges or networks in one-sample-for-one-individual *** also provides a powerful tool for precision medicine or big-data medicine.

关键词： edge biomarker edge feature progressive stages disease diagnosis big biological data