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Different headspace profiles in wild crucifer species in response to Plutella xylostella herbivory and exogenous jasmonic acid application

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Insect Science 2010年第1期17卷 29-37页

作者： peng-jun Zhang Jin-Ping Shu Marcel Dicke Shu-sheng Liu Institute of Insect Sciences Zhejiang University Hangzhou China Laboratory of Entomology Wageningen University Wageningen The Netherlands

Although exogenous treatment of plants withjasmonic acid （JA） may result in induced responses similar to plant defences induced by herbivory, few studies have compared the details of insect herbivory and JA-mimicked responses. We compared volatiles of two crucifer species, Cardamine impatiens and Lepidium virginicum, in response to Plutella xylostella larval feeding and exogenous application of JA, over the entire period of time when induced changes were detectable. Significant differences in the composition and timing of volatiles occurred between herbivory and JA treatments in both plants. The quantity ofnitrile and isothiocyanate released in response to herbivory was significantly larger than that upon JA treatment. In each of the two plant species, most volatile components were emitted immediately upon larval feeding and their quantity dropped rapidly once feeding ceased. In contrast, the emission of volatiles in response to JA treatment lasted for a longer period of time, and the maximum emission rate was recorded 2 and 3 days after JA treatment in L. virginicum and C. impatiens respectively. These findings are discussed in the context of signal-transduction pathways and mechanisms involved in induced emissions of plant volatiles, as well as induced defences mediated by plant volatiles.

关键词： Brassicaceae herbivory induced response jasmonic acid Plutella xylostella volatile emission

Structural and electrical properties of HCl–polyaniline–Ag composites synthesized by polymerization using Ag-coated (NH_4)_2S_2O_8 powder

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1329-1334页

作者： You Zhou Yu-he Zhang jun-sheng Ma Ming-peng Yu Hong Qiu School of Mathematics and Physics University of Science and Technology Beijing

Ag nanoparticles were sputter-deposited on ammonium persulfate((NH_4)_2S_2O_8) powder to obtain(NH_4)_2S_2O_8-Ag powder, which was used to synthesize the HCl-doped polyaniline-Ag(HCl-PANI-Ag) composite via a polymerization procedure. The Ag nanoparticles were dispersed in the HCl-PANI matrix, and their sizes mainly ranged from 3 to 6 nm. The Ag nanoparticles did not affect the structure of emeraldine salt in the composite, and they increased the ordered crystalline regions in the HCl-PANI matrix. The HCl-PANI-Ag composite had a conductivity of(6.8 ± 0.1) S/cm, which is about four times larger than that of the HCl-PANI. The charge transport mechanism in the composite is explained by the three-dimensional Mott variable-range hopping(3D-Mott-VRH).

关键词： hydrochloric-acid-doped polyaniline silver nanoparticles composite structure conductivity

胃癌患者肝转移和腹膜扩散的相关因素及其预后分析

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中华胃肠外科杂志 2006年第4期9卷 287-290页

作者：王昭詹文华何裕隆蔡世荣彭俊生陈创奇马晋平郑章清中山大学附属第一医院胃肠胰外科中山大学胃癌诊治中心广州510080

目的探讨胃癌患者肝转移和腹膜扩散的相关临床病理因素和近远期预后以及姑息性手术对预后的影响。方法回顾性分析1994年8月至2005年7月间胃癌数据库资料中792例患者的临床病理资料和随访结果。结果本组患者肿瘤穿透浆膜、淋巴结转移、... 详细信息

目的探讨胃癌患者肝转移和腹膜扩散的相关临床病理因素和近远期预后以及姑息性手术对预后的影响。方法回顾性分析1994年8月至2005年7月间胃癌数据库资料中792例患者的临床病理资料和随访结果。结果本组患者肿瘤穿透浆膜、淋巴结转移、肝转移、全胃癌、未分化癌、BorrmannⅣ型、女性患者因素与腹膜扩散相关,而BorrmannⅣ型、淋巴结转移、腹膜扩散与胃癌肝转移相关(P＜0．05)。肝转移患者1年生存率低于腹膜扩散患者(P＜0．05)；而3、5年生存率两者差异无统计学意义(P＞0．05)。腹膜扩散组中姑息性切除术患者1年生存率高于旁路手术/喂食性造口术和剖腹探查患者(P＜0．05)；而肝转移患者3种手术者1、3、5年生存率比较,差异无统计学意义(P＞0．05)。结论有肝转移的胃癌患者近期预后比腹膜扩散患者差；姑息性切除术可改善腹膜扩散胃癌患者的近期生存率,而对肝转移患者影响不明显。

关键词：胃肿瘤肝转移腹膜扩散生存率

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小型仿人足球机器人控制系统

兵工自动化 2010年第2期29卷 77-80页

作者：金晓飞彭胜军张瑞永马宏绪国防科学技术大学机电工程与自动化学院湖南长沙410073

针对当前小型仿人足球机器人在足球比赛中的复杂任务背景,设计了可实时在线路径规划的小型仿人足球机器人控制系统。基于Robotis公司的Dynamixel系列AX-12型舵机和标准连接件设计了具有20个自由度的仿人足球机器人本体结构;基于运算速... 详细信息

针对当前小型仿人足球机器人在足球比赛中的复杂任务背景,设计了可实时在线路径规划的小型仿人足球机器人控制系统。基于Robotis公司的Dynamixel系列AX-12型舵机和标准连接件设计了具有20个自由度的仿人足球机器人本体结构;基于运算速度较高的DSP芯片TMS320F2812设计了主控制器;应用CMUcam3视觉传感子系统进行图像采集和处理,将获得的目标位置反馈给主控制器,完成基于视觉伺服控制的实时路径规划任务。目前,该仿人足球机器人可以在实验室环境中完成稳定直走、转弯和准确踢球等运动规划任务。下一步将重点研究最小损伤下的跌倒控制、爬起和不同动作单元的动态切换等复杂任务和多个仿人足球机器人的协调控制。

关键词：仿人足球机器人 DynamixelAX-12舵机数字信号处理器 TMS320F2812 CMUcam3

A comparative study of the self-propelled jumping capabilities of coalesced droplets on RTV surfaces and superhydrophobic surfaces

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Chinese Physics B 2021年第4期30卷 409-416页

作者： sheng-Wu Wang Lu peng jun-Wu Chen Lee Li School of Electrical and Electronic Engineering Huazhong University of Science&TechnologyWuhan 430074China

Understanding the mechanism of coalescence-induced self-propelled jumping behavior provides distinct insights in designing and optimizing functional coatings with self-cleaning and anti-icing ***,to date self-propelled jumping phenomenon has only been observed and studied on superhydrophobic surfaces,other than those hydrophobic surfaces with weaker but fairish water-repellency,for instance,vulcanized silicon rubber(RTV) *** this work,from the perspective of thermodynamic-based energy balance aspect,the reason that self-propelled jumping phenomenon does not happen on RTV coatings is *** apparent contact angles of droplets on RTV coatings can be less than the theoretical critical values therefore cannot promise energy surplus for the coalesced droplets ***,on RTV and superhydrophobic surfaces,the droplet-size dependent variation characteristics of the energy leftover from the coalescence process are *** the droplets coalescing on RTV coatings,the magnitudes of energy dissipations are more sensitive to the increase in droplet size,compared to that of released surface *** for superhydrophobic coatings,the energy generated during the coalescence process can be more sensitive than the dissipations to the change in droplet size.

关键词： self-propelled jumping vulcanized silicon rubber(RTV) superhydrophobicity self-cleaning

siRNA电转化幽门螺杆菌抑制空泡毒素基因mRNA表达

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中国病理生理杂志 2007年第11期23卷 2244-2247页

作者：赵刚严燕国马晋平彭俊生董文广蔡世荣何裕隆詹文华中山大学第一附属医院胃肠胰外科中山大学胃癌诊治中心广东省人民医院

目的:利用RNA干扰(RNAi)技术原理,优化小分子干扰RNA(siRNA)电转化幽门螺杆菌(Hp)的条件,并观察电转化后空泡毒素基因(VacA)的mRNA表达是否受到抑制。方法:合成5对特异siRNA为实验组:S1、S2、S3、S4、S5,1对非特异siRNA为对照组:S6。设... 详细信息

目的:利用RNA干扰(RNAi)技术原理,优化小分子干扰RNA(siRNA)电转化幽门螺杆菌(Hp)的条件,并观察电转化后空泡毒素基因(VacA)的mRNA表达是否受到抑制。方法:合成5对特异siRNA为实验组:S1、S2、S3、S4、S5,1对非特异siRNA为对照组:S6。设定不同的电场强度及脉冲时间,探索电转化Hp的最佳条件,并观察转化效率和电转化后Hp存活率。在最佳电转化条件下将上述6对siRNA转化Hp,在不同时点通过RT-PCR方法检测VacA mRNA的抑制率。结果:电场强度和脉冲时间是影响电转化效率的2个关键因素,在25kV/cm电场强度下脉冲6ms时,电转化效率最高达91%,S2、S4组在转化后VacA mRNA抑制率分别为65%和77%。结论:适当的场强和脉冲时间的组合可使转化效率达到最大值。靶向siRNA可以抑制HpVacA的mRNA表达。

关键词：电转化螺杆菌幽门 RNA干扰基因 VacA

A Unified Thermodynamic Model of Flow-induced Crystallization of Polymer

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Chinese Journal of Polymer Science 2021年第11期39卷 1489-1495页

作者： Cui Nie Fan peng Ting-Yu Xu jun-Fang sheng Wei Chen Liang-Bin Li National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Science and Technology of ChinaHefei 230026China

We propose a unified thermodynamic model of flow-induced crystallization of polymer(uFIC),which incorporates not only the conformational entropy reduction but also the contributions of flow-induced chain orientation,the interaction of ordered segments,and the free energy of crystal nucleus and crystal ***,it clarifies the determining parameters of the critical crystal nucleus size,and is able to account for the acceleration of nucleation,the emergence of precursor,different crystal morphologies and structures induced by *** on the nucleation barrier under flow,we analyze at which condition precursor may occur and how flow affects the competition among different crystal forms such as orthorhombic and hexagonal phases of *** to the uFIC model,the different crystal morphologies and structures in the flow-temperature space have been clarified,which give a good agreement with experiments of FIC.

关键词： Flow-induced crystallization Unified thermodynamic model Flow-induced chain orientation

L^(p)Solution of Reflected BSDEs with One Continuous Barrier and Quasi-linear Growth Generators

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 943-953页

作者： sheng-jun FAN School of Mathematics China University of Mining and TechnologyXuzhou 221116China

This paper is devoted to solving a reflected backward stochastic differential equation(BSDE in short)with one continuous barrier and a quasi-linear growth generator g,which has a linear growth in(y,z),except the upper direction in case of y1)solutions for the reflected *** also prove that the minimal Lpsolution can be approximated by a sequence of Lpsolutions of certain reflected BSDEs with Lipschitz generators.

关键词： Reflected BSDEs Quasi-linear growth L^(p)solution Existence Comparison theorem

New Members of High-Energy-Density Compounds: YN5 and YN8

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Chinese Physics Letters 2021年第6期38卷 49-53页

作者： jun-Yi Miao Zhan-sheng Lu Feng peng Cheng Lu School of Physics Henan Normal UniversityXinxiang 453007China College of Physics and Electronic Information Luoyang Normal UniversityLuoyang 471022China School of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China

Polymeric nitrogen is a promising candidate for a high-energy-density material. Synthesis of energetic compounds with high chemical stability under ambient conditions is still a challenging problem. Here we report a theoretical study on yttrium nitrides by first principles calculations combined with an effective crystal structure search method. It is found that many yttrium nitrides with high nitrogen content can be formed under relatively moderate pressures. The results indicate that the nitrogen-rich YN_(5) and YN_(8) compounds are recoverable as metastable high-energy materials under ambient conditions, and can release enormous energies(2.51 kJ·g^(-1) and 3.18 kJ·g^(-1)) while decomposing to molecular nitrogen and YN. Our findings enrich the family of transition metal nitrides, and open avenues for design and synthesis of novel high-energy-density materials.

关键词： material ambient yttrium