检索结果-南通市图书馆

In vitro regeneration of Populus tomentosa from petioles

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2017年第3期28卷 465-471页

作者： fang Wei fang-fang Zhao Bao-ming Tian School of life Sciences Zhengzhou University

A reliable in vitro regeneration procedure for Populus tomentosa is a prerequisite for its trait improvement through genetic transformation. We established a systematic protocol for indirect regeneration of P. tomentosa using in vitro petioles of Chinese poplar cultivar ＇fasta-3＇. A high frequency of callus induction （〉97 %） was obtained from isolated petioles cultured on the modified 1/2MS basal medium supplemented with 0.5 mg/l ZT and 1.0 mg/l NAA, and the tested calli were subsequently plated on 1/2MS basal medium supplemented with 0.25 mg/l BA, 0.25 mg/l ZT, 0.25 mg/l NAA, 0.01 mg/l TDZ, and 0.5 mg/l KT for efficient regeneration of shoots after being cultured for 6 weeks. The regenerated shoots were vigorously rooted on the tested media supplemented with 1.0 mg/ l IBA and 0.5 mg/l NAA. These results can facilitate genetic transformation of P. tomentosa for trait improvements in future.

关键词： Callus induction Genetic transformation In vitro regeneration Petiole Populus tomentosa

Effect of friction stir processing on microstructure and damping capacity of AZ31 alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2017年第5期24卷 1034-1039页

作者： ZANG Qian-hao CHEN Hong-mei lAN fang-yuan ZHANG jing jin Yun-xue Provincial Key lab of Advanced Welding Technology Jiangsu University of Science and TechnologyZhenjiang 212003China Key laboratory for liquid-Solid Structural Evolution&Processing of Materials of Ministry of Education Shandong UniversityJinan 250061China National Demonstration Center for Experimental Materials Science and Engineering Education(Jiangsu University of Science and Technology) Zhenjiang 212003China

AZ31 alloy sheet fabricated by rolling was processed by friction stir processing(FSP) with different passes. The effect of FSP on the microstructure and damping capacity of AZ31 alloy sheet was discussed. The fine and equiaxed grains were obtained in the stirred zone(SZ) for FSPed samples from 1 pass to 3 passes with the average grain size of 10.6, 10.4 and 13.6 μm, respectively. The damping peak P_1 was presented on the curves of temperature-dependent damping capacity for FSPed samples. The damping peak P_2 was restrained after FSP and the damping peak P_1 was a relaxation process. The FSPed samples(2-pass FSP and 3-pass FSP) obtained high damping capacity. The best damping valuesQ_0^(-1)(ε=10_(-4)) and damping values Q_H^(-1)(ε=10^(-3)) of the sample subjected to 3-pass FSP(0.0131 and 0.0496) increased by 33.7% and 157.0%, respectively.

关键词： Mg-Al-Zn alloy (AZ31) friction stir processing (FSP) damping peak G-l model

Effect of Cyclic Annealing on Microstructure and Mechanical Properties of Medium Carbon 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 2016年第2期23卷 145-150页

作者： Zhi-qing lÜ Hui-fang ZHANG Qing MENG Zhen-hua WANG Wan-tang FU College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina State Key laboratory of Metastable Material Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

The microstructure and mechanical properties of medium carbon steel after cyclic heat treatment were in- vestigated. The effects of cyclic numbers and long time annealing on the microstructure and mechanical properties of the experimental steel were compared. A short duration （5 min） holding at 1023 K （above A1 temperature） and a short-duration （3 min） holding at 893 K are adopted in each cyclic heat treatment. The spheroidization is accelerated during cyclic heat treatment, and the spheroidizing ratio grows with cyclic numbers. After 12-cycle heat treatments, there are few incompletely spheroidized regions in the specimens, and cementite lamellae mostly change into cement- ite particles. The morphological character of cementite for 12 cycles is similar to that undergoing annealing for 10 h at 973 K. The strength of the experimental steel after 5-cycle heat treatment is the lowest in the following cyclic heat treatment, but it is still higher than that of specimens with subcritical annealing over a long period （10 h）. After 12- cycle heat treatment, the strength of the experimental steel is close to that of the normalized steel, and the plasticity is the best in all heat treated specimens.

关键词： rapid spheroidizing mechanical property cyclic annealing cementite medium carbon steel

Practical automatic background substitution for live video

在线全文

学校读者我要写书评

暂无评论

Computational Visual Media 2017年第3期3卷 273-284页

作者： Haozhi Huang Xiaonan fang Yufei Ye Songhai Zhang Paul l.Rosin Department of Computer Science Tsinghua University School of Computer Science and Informatics Cardiff University

In this paper we present a novel automatic background substitution approach for live video. The objective of background substitution is to extract the foreground from the input video and then combine it with a new background. In this paper, we use a color line model to improve the Gaussian mixture model in the background cut method to obtain a binary foreground segmentation result that is less sensitive to brightness differences. Based on the high quality binary segmentation results, we can automatically create a reliable trimap for alpha matting to refine the segmentation boundary. To make the composition result more realistic, an automatic foreground color adjustment step is added to make the foreground look consistent with the new background. Compared to previous approaches, our method can produce higher quality binary segmentation results, and to the best of our knowledge, this is the first time such an automatic and integrated background substitution system has been proposed which can run in real time, which makes it practical for everyday applications.

关键词： background substitution background replacement background subtraction alpha matting

Roles of tensor and isoscalar pairing interactions in β-decay calculations for possible r-process waiting point nuclei with N~82 and 126

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2022年第11期46卷 221-230页

作者： C.l.Bai D.l.fang H.Q.Zhang School of physics science and technology Sichuan UniversityChengdu 610065China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science University of Chinese Academy of SciencesBeijing 100049China China Institute of Atomic Energy Beijing 10400China

In this study,we adopt the self-consistent Hartree-Fock-Bogoliubov(HFB) theory with the proton-neutron quasi-particle random phase approximation(pnQRPA) based on the Skyrme force for calculation of the β^(-) -decay half-lives for nuclei with N~82 and 126 on possible r-process *** the calculations,the Skyrme interaction(e.g.,SKO’) is adopted,and the tensor interaction is added self-consistently in both HFB and QRPA *** systematically study how the half-life is changed by varying the strength of the triplet-even(TE) and triplet-odd(TO) components as well as the IS *** find that a variation in strength of the IS pairing of approximately 20% does not produce a substantial effect on β-decay rates with or without the tensor force,while a strength variation of the TO tensor force considerably affects the change in the β-decay half-lives for the very neutron rich N~82 and 126 isotonic *** addition,with the inclusion of the tensor force,the GT decay becomes dominant for very neutron-rich nuclei.

关键词： nuclear structure weak decay density functional theory

Analyzing the inconsistency in driving patterns between manual and autonomous modes under complex driving scenarios with a VR-enabled simulation platform

在线全文

学校读者我要写书评

暂无评论

Journal of Intelligent and Connected Vehicles 2022年第3期5卷 215-234页

作者： Zheng Xu Yihai fang Nan Zheng Hai l.Vu Department of Civil Engineering Monash UniversityClaytonAustralia

Purpose–With the aid of naturalistic simulations,this paper aims to investigate human behavior during manual and autonomous driving modes in complex ***/methodology/approach–The simulation environment is established by integrating virtual reality interface with a micro-simulation *** the simulation,the vehicle autonomy is developed by a framework that integrates artificial neural networks and genetic ***subject experiments are carried,and participants are asked to virtually sit in the developed autonomous vehicle(AV)that allows for both human driving and autopilot functions within a mixed traffic ***–Not surprisingly,the inconsistency is identified between two driving modes,in which the AV’s driving maneuver causes the cognitive bias and makes participants feel *** though only a shallow portion of the cases that the AV ended up with an accident during the testing stage,participants still frequently intervened during the AV *** a similar note,even though the statistical results reflect that the AV drives under perceived high-risk conditions,rarely an actual crash can *** suggests that the classic safety surrogate measurement,***-tocollision,may require adjustment for the mixed traffic *** limitations/implications–Understanding the behavior of AVs and the behavioral difference between AVs and human drivers are important,where the developed platform is only the first effort to identify the critical scenarios where the AVs might fail to *** implications–This paper attempts to fill the existing research gap in preparing close-to-reality tools for AV experience and further understanding human behavior during high-level autonomous *** implications–This work aims to systematically analyze the inconsistency in driving patterns between manual and autopilot modes in various driving scenarios(*** scenes and various traffic conditions)to facilitate user accep

关键词： Autonomous vehicle Naturalistic simulation Virtual reality Cognitive bias Intervention behavior

Survey of E-Commerce Modeling and Optimization Strategies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2005年第z1期10卷 761-771页

作者： WANG Dingwei NUTTlE Henry l.W. fang Shu-Cherng School of Information Science and Engineering Northeastern University Shenyang 110004 China Department of Industrial Engineering North Carolina State University Raleigh NC 27695 USA Department of Industrial Engineering North Carolina State University Raleigh NC 27695 USA

Electronic commerce is impacting almost all commercial activities. The resulting emerging commercial activities bring with them many new modeling and optimization problems. This survey reviews pioneering works in this new area, covering topics in advertising strategy, web page design, automatic pricing, auction methods, brokerage strategy, and customer behavior analysis. Mathematical models for problems in these areas and their solution algorithms are discussed. In addition to presenting and commenting on these works, we also discuss possible extensions and related problems. The objective of this survey is to encourage more researchers to pay attention to this emerging area.

关键词： electronic commerce modeling and optimization advertising web link pricing auction brokerage customer behavior

Mitochondrion-anchoring AIEgen with large Stokes Shift for Imaging-guided Photodynamic Therapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2021年第1期37卷 137-142页

作者： fang fang GAO Yuting lUO liang National Engineering Research Center for Nanomedicine College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan430074P.R.China Hubei Key laboratory of Bioinorganic Chemistry and Materia Medica School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074P.R.China

Photosensitizers that can target and accumulate in mitochondria are expected to achieve good therapeutic effects in photodynamic therapy,as mitochondria are the energy generation factory in ***,we designed and synthesized a novel mitochondrion-targeting photosensitizer TPC-Py with aggregation-induced emission characteristics for image-guided photodynamic ***-Py possessed an efficient production of 1O2,with a quantum yield of 11.65%,upon mild white light irradiation(6 mW/cm^(2)).TPC-Py exhibited good biocompatibility under dark condition,but showed remarkable cytotoxicity towards human cervical carcinoma(Hela)cells with a half maximal inhibitory concentration(IC50)of 3.2µmol/l when exposed to white light irradiation(14.4 J/cm^(2)).In addition,the Stokes shift of TPC-Py was as high as 150 nm,so that it could prevent self-absorption and increase the signal-to-noise ratio of fluorescence *** excellent performance of TPC-Py makes it a promising candidate in imaging-guided clinical PDT for cancer in the near future.

关键词： Photodynamic therapy Photosensitizer Aggregation-induced emission Mitochondria Imaging-guided

Maternal sleep deprivation disrupts glutamate metabolism in offspring rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第6期45卷 1221-1231页

作者： Wen-Ting He Dong-Xu li jin-Hua Fan Zheng-Yu Yao Yu-Peng Cun Zhi-fang Dong Growth Developmentand Mental Health of Children and Adolescence CenterPediatric Research InstituteMinistry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChongqing Key Laboratory of Child Neurodevelopment and Cognitive DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China

Maternal sleep deprivation(MSD)has emerged as a significant public health concern,yet its effects on offspring metabolism remain poorly *** study investigated the metabolomic implications of MSD on offspring cognitive development,with a particular focus on alterations in glutamate *** rats were subjected to sleep deprivation during late *** and brain samples from their offspring were collected at different postnatal days(P1,P7,P14,and P56)and analyzed using untargeted metabolomics with liquid chromatography-mass *** analysis revealed significant differences in various amino acids,including l-glutamate,l-phenylalanine,l-tyrosine,and l-tryptophan,which are crucial for cognitive *** differential analysis and partial least squares discriminant analysis(sPlS-DA)demonstrated a gradual reduction in these metabolic differences in the brain as the offspring underwent growth and *** pathway analysis revealed differential regulation of several pathways,including alanine,aspartate,and glutamate metabolism,glutathione metabolism,arginine biosynthesis,aminoacyl-tRNA biosynthesis,histidine metabolism,and taurine and hypotaurine metabolism,at different developmental *** and Spearman analyses indicated that the observed changes in metabolites in MSD progeny may be related to various gut microbes,Ruminococcus_1,Ruminococcaceae_UCG-005,and Eubacterium_coprostanoligenes_*** assays further demonstrated developmental changes in the l-glutamate metabolic ***,these findings suggest that MSD not only affects maternal wellbeing but also has enduring metabolic consequences for offspring,particularly impacting pathways linked to cognitive *** highlights the importance of addressing maternal sleep health to mitigate potential long-term consequences for offspring.

关键词： Maternal sleep deprivation Glutamate metabolism Metabolomics Cognitive development Offspring