检索结果-南通市图书馆

How does the host-specialized aphid deal with food deficiency？

Insect Science 2014年第3期21卷 334-341页

作者： ting-ting Xu ting-ting ma Xiang-Dong Liu Department of Entomology Nanjing Agricultural University Nanjing China

Aphis gossypii Glover shows obvious host specialization, with cucurbit- and cotton-specialized biotypes or host races in many regions. Because its annual natal hostcrops senesce earlier the cucurbit-specialized biotype may suffer food deficiency. The method this biotype uses to overcome this challenge is still poorly understood. In orderto understand the potential of the cucurbit-specialized biotype aphids in host shift and usage, the performance of this biotype on cotton （Gossypium hirsutum）, a common butpoor quality host plant, was explored in this study. The cucurbit-specialized aphids could establish populations on cotton only when these plants had at least nine leaves, and subsequent populations developed rather slowly. The presence of whitefly populations on cotton improved the success rate of cucurbit-specialized aphids. The cucurbit-specialized aphidswere mainly distributed on the older leaves of cotton, with only a few settling on the upper leaves. The cucurbit-specialized aphids reared on cotton for 40, 54 and 61 days stillmaintained strong preference for their natal host plant, cucumber （Cucumis sativus）, rather than cotton, and their net reproductive rates and intrinsic rates of natural increase weredramatically lower when they were transferred onto new six-leaf cotton plants or detached leaves. Therefore, we concluded that the cucurbit-specialized aphids have the potentialto utilize mature or whitefly-stressed cotton plants, but that this feeding experience on cotton did not alter their specialization for cucurbits. Some cotton plants could act as atemporary host for the cucurbit-specialized aphids to overcome food deficiency arising from senescing cucurbits.

关键词： Aphidgossypii cotton-melon aphid host shift host specialization temporary host whitefly-stressed cotton

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Limiting Behaviors for Longest Consecutive Switches in anⅡD Bernoulli Sequence

引用

Acta mathematica Sinica,English Series 2023年第6期39卷 1138-1146页

作者： Chen Xu HAO ting ma College of mathematics Sichuan UniversityChengdu 610065P.R.China

In this paper we mainly discuss lower and upper bounds for the length of longest consecutive switches inⅡD Bernoulli *** work is an extension of results for longest consecutive switches in unbiased coin-tossing,and m... 详细信息

关键词： Longest consecutive switches lower and upper bounds Borel-Cantelli lemma

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Convergence Rate for Galerkin Approximation of the Stochastic Allen–Cahn Equations on 2D Torus

引用

Acta mathematica Sinica,English Series 2021年第3期37卷 471-490页

作者： ting ma Rong Chan ZHU College of mathematics Sichuan UniversityChengdu 610065P.R.China Department of mathematics Beijing Institute of TechnologyBeijing 100081P.R.China Department of mathematics University of BielefeldD-33615 BielefeldGermany

In this paper we discuss the convergence rate for Galerkin approximation of the stochastic Allen–Cahn equations driven by space-time white noise on T^(2). First we prove that the convergence rate for stochastic 2D heat equation is of order α-δ in Besov space C^(-α) for α∈(0, 1) and δ > 0 arbitrarily small. Then we obtain the convergence rate for Galerkin approximation of the stochastic Allen–Cahn equations of order α-δ in C^(-α) for α∈(0, 2/9) and δ > 0 arbitrarily small.

关键词： Stochastic Allen–Cahn equations convergence rate Galerkin projection Besov space white noise

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Variable Selection in Joint Location, Scale and Skewness Models of the Skew-Normal Distribution

引用

Journal of Systems Science & Complexity 2017年第3期30卷 694-709页

作者： LI Huiqiong WU Liucang ma ting Department of Statistics Yunnan University Faculty of Science Kunming University of Science and Technology

Variable selection is an important research topic in modern statistics, traditional variable selection methods can only select the mean model and(or) the variance model, and cannot be used to select the joint mean, variance and skewness models. In this paper, the authors propose the joint location, scale and skewness models when the data set under consideration involves asymmetric outcomes,and consider the problem of variable selection for our proposed models. Based on an efficient unified penalized likelihood method, the consistency and the oracle property of the penalized estimators are established. The authors develop the variable selection procedure for the proposed joint models, which can efficiently simultaneously estimate and select important variables in location model, scale model and skewness model. Simulation studies and body mass index data analysis are presented to illustrate the proposed methods.

关键词： Joint location scale and skewness models penalized maximum likelihood estimation skew-normal distribution variable selection.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Targeting epigenetic regulators to overcome drug resistance in cancers

引用

Signal Transduction and Targeted Therapy 2023年第3期8卷 1070-1093页

作者： Nan Wang ting ma Bin Yu Institute of Drug Discovery&Development School of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001China

Drug resistance is mainly responsible for cancer recurrence and poor *** regulation is a heritable change in gene expressions independent of nucleotide sequence *** the common epigenetic regulation mechanisms,DNA methylation,histone modification,and non-coding RNA regulation have been well *** evidence has shown that aberrant epigenetic regulations contribute to tumor ***,targeting epigenetic regulators represents an effective strategy to reverse drug *** this review,we mainly summarize the roles of epigenetic regulation in tumor *** addition,as the essential factors for epigenetic modifications,histone demethylases mediate the histone or genomic DNA ***,we comprehensively describe the functions of the histone demethylase family including the lysine-specific demethylase family,the Jumonji C-domain-containing demethylase family,and the histone arginine demethylase family,and fully discuss their regulatory mechanisms related to cancer drug *** addition,therapeutic strategies,including small-molecule inhibitors and small interfering RNA targeting histone demethylases to overcome drug resistance,are also described.

关键词： epigenetic drug overcome

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effect of heat treatments on Charpy impact properties of 15Cr12MoVWN ferritic/martensitic steel

引用

Journal of Iron and Steel Research International 2022年第3期29卷 512-518页

作者： ting-wei ma Xian-chao Hao Ping Wang Key Laboratory of Electromagnetic Processing of materials Ministry of EducationNortheastern UniversityShenyang110819LiaoningChina Yingkou Institute of Technology Yingkou115014LiaoningChina CAS Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina

The Charpy impact properties of 15Cr12MoVWN ferritic/martensitic steel for sodium-cooled reactors with variation in heat treatment factors and parameters are *** results show that the ductile-to-brittle transition temperature(DBTT)increased and the upper shelf energy(USE)decreased with increase in normalizing ***,the variation tendency of DBTT and USE was the opposite with increase in tempering *** tempering temperature showed a greater influence on USE than the normalizing temperature,and normalizing and tempering temperatures had the equally significant effects on DBTT,but the cooling method was not a significant factor for DBTT and *** prior austenite grain and M_(23)C_(6) size were the main influences on DBTT,and the dislocation density was the main factor affecting the variation of *** heat-treatment regime recommended for 15Cr12MoVWN steel was composed of normalizing at 1000-1050℃ for 0.5 h followed by water quenching or air cooling and tempering at 760℃ for 1.5 h.

关键词： 15Cr12MoVWN steel Ductile-to-brittle transition temperature Prior austenite grain size M23C6-MX

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A large-scale clustering and 3D trajectory optimization approach for UAV swarms

引用

Science China(Information Sciences) 2021年第4期64卷 84-99页

作者： ting ma Haibo ZHOU Bo QIAN Aiyong FU School of Electronic Science and Engineering Nanjing University

With the significant development of unmanned aerial vehicles(UAVs) technologies, a rapid increase on the use of UAV swarms in a wide range of civilian and emergency applications has been ***, how to efficiently network the large-scale UAVs and implement the swarms applications without infrastructure support in remote areas is challenging. In this paper, we investigate a hierarchal large-scale infrastructure-less UAV swarm scenario, where numerous UAVs surveil and collect data from the ground and a ferry UAV(Ferry UAV) is designated to carry back all their collected data. We can divide UAV swarms into different areas based on their geographic locations due to the wide range of surveillance. To improve data collection efficiency of Ferry UAV, we introduce a single super cluster head(Super-CH) UAV in each area which can be selected by the proposed modified k-means clustering algorithm with low latency. Then,we design an iterative approach to optimize the 3-dimensional(3D) trajectory of Ferry UAV such that its data collection mission completion time is minimized. Numerical results show the efficiency and low-latency of the proposed clustering algorithm, and the proposed 3D optimal trajectory design for large-scale UAV swarms data collection admits better performance than that with fixed altitude.

关键词： large-scale UAV swarms clustering super-CH selection 3D trajectory design

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Prediction of Equivalent Thermal Conduction Resistance of Printed Circuit Heat Exchangers

引用

Journal of Thermal Science 2022年第6期31卷 2281-2292页

作者： SHI Haoning CHANG Hongliang ma ting WANG Qiuwang Key Laboratory of Thermo-Fluid Science and Engineering MOEXi’an Jiaotong UniversityXi'an 710049China

Printed circuit heat exchangers(PCHEs) have great potential to be employed in the advanced nuclear reactor systems. In this work, the equivalent thermal conduction resistance of PCHE is studied. The influences of thermal convection resistance are analyzed. The results indicate that the equivalent thermal conduction resistance of PCHEs with unequal numbers of hot plates and cold plates are sensitive to the thermal convection resistance of hot side and cold side. Specifically, for case C which has unequal number of hot and cold channels, the maximum value of equivalent thermal conduction resistance can be 1.7-2.4 times the minimum value. The equivalent thermal conduction resistance is underestimated under the isothermal boundary. In addition, the non-uniformity of the lengths of all the heat flux lines determines the influence degree of thermal convection resistance on the equivalent thermal conduction resistance. For further investigation, Latin hypercube sampling method is adopted to generate a large number of design points for each PCHE configuration. Based on the sample data, mathematical correlations and artificial neural network(ANN) for prediction of equivalent thermal conduction resistance for each case are developed. The proposed correlations of equivalent thermal conduction resistance for each case have acceptable accuracy of prediction with a wide range covering general engineering applications. The ANN model can achieve much better prediction accuracy than the proposed correlations thus it is recommended in the cases that the prediction accuracy is considered as the priority need.

关键词： equivalent thermal conduction resistance printed circuit heat exchanger numerical calculation correlations artificial neural network

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Physiological and Antioxidant Responses of Germinating Mung Bean Seedlings to Phthalate Esters in Soil

引用

Pedosphere 2014年第1期24卷 107-115页

作者： ma ting-ting P.CHRISTIE LUO Yong-Ming TENG Ying Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences University of Chinese Academy of Sciences Agri-Environment Branch Agri-Food and Biosciences Institute Yantai Institute of Costal Zone Research Chinese Academy of Sciences

Single phytotoxicity of two representative phthalate esters(PAEs),di-n-butyl phthalate(DnBP)and bis(2-ethylhexyl)phthalate(DEHP),was tested in mung bean(Vigna radiata)seedlings germinated for 72 h in soils spiked with varying concentrations(0-500 mg kg^(-1)soil)of DnBP or *** added at up to 500 mg kg^(-1)soil exerted no significant effect on germination but both pollutants significantly inhibited root elongation(Pmass on a fresh weight basis(Pmalondialdehyde(MDA)contents tended to be stimulated by DnBP but inhibited by ***,increases in superoxide dismutase,peroxidase,ascorbate peroxidase and polyphenol oxidase activities,as well as glutathione(GSH)content,were induced at higher concentrations(e.g.,20 mg kg^(-1))of both *** of proline in both roots and shoots and the storage compounds,such as free amino acids and total soluble sugars,in whole plant was induced under the stress exerted by both *** general responses of mung bean seedlings indicated higher toxicity of DnBP than DEHP on primary growth,during which root elongation was a more responsive *** and GSH were more sensitive parameters in the roots than in the shoots and they might be recommended as physiologically sensitive parameters to assess the toxicity of PAE compounds in soils in future long-term studies.

关键词： glutathione malondialdehyde phytotoxicity root elongation storage compounds

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multi-Field Analysis and Experimental Verification on Piezoelectric Valve-Less Pumps Actuated by Centrifugal Force

引用

Chinese Journal of Mechanical Engineering 2017年第4期30卷 1032-1043页

作者： Yu-ting ma Zhi-Guo Pei Zhong-Xiang Chen CAS Key Lab of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163China

A piezoelectric centrifugal pump was developed previously to overcome the low frequency responses of piezoelectric pumps with check valves and liquid reflux of conventional valveless piezoelectric pumps. However, the electro-mechanical-fluidic analysis on this pump has not been done. Therefore, multi-field analysis and experimen- tal verification on piezoelectrically actuated centrifugal valveless pumps are conducted for liquid transport appli- cations. The valveless pump consists of two piezoelectric sheets and a metal tube with piezoelectric elements pushing the metal tube to swing at the first bending resonant fre- quency. The centrifugal force generated by the swinging motion will force the liquid out of the metal tube. The governing equations for the solid and fluid domains are established, and the coupling relations of the mechanical, electrical and fluid fields are described. The bending res- onant frequency and bending mode in solid domain are discussed, and the liquid flow rate, velocity profile, and gauge pressure are investigated in fluid domain. The working frequency and flow rate concerning different components sizes are analyzed and verified through experiments to guide the pump design. A fabricated pro- totype with an outer diameter of 2.2 mm and a length of 80 mm produced the largest flow rate of 13.8 mL/min at backpressure of 0.8 kPa with driving voltage of 80 Vpp. Bysolving the electro-mechanical-fluidic coupling problem, the model developed can provide theoretical guidance on the optimization of centrifugal valveless pump characters.

关键词： Valveless pump Centrifugal force Piezoelectric pump Multi-field analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：