检索结果-南通市图书馆

Changes in Phyto-Chemical Status upon Viral Infections in Plant:A Critical Review

Phyton-International Journal of Experimental Botany 2021年第1期90卷 75-86页

作者： Tehmina Bahar Adeeba Mahboob Qureshi Fasiha Qurashi muniba abid Misbah Batool Zahra Muhammad Saleem Haider Institute of Agricultural Sciences University of the PunjabLahore54590Pakistan Department of Forestry Range and Wildlife ManagementUniversity College of Agriculture and Environmental SciencesThe Islamia University of BahawalpurBahawalpur63100Pakistan

Most damaging plant diseases have been caused by viruses in the entire *** tropical and subtropical areas,the damage caused by plant virus leads to great economic and agricultural *** stranded DNA viruses(geminiviruses)are the most perilous pathogens which are responsible for major diseases in agronomic and horticultural *** begomoviruses and mastreviruses are the biggest genus of plant infecting viruses,transmitted though Bemisia tabaci and members of Cicadellidae *** possesses some naturally existing chemicals term as phyto-chemicals which perform important functions in the *** antioxidant enzymes are used by plants for selfdefense upon foreign invasion of *** review explains the present perceptive of influence of viral infections on phyto-chemicals,oxidative enzymes and biochemical changes occurring in the *** infection mediated phytochemical changes in plants mainly includes:up and down regulation of photosynthetic pigment,increase in the concentration of phenolic compounds,elevation of starch content in the leaf and up&down regulation of anti-oxidative enzymes including(GPX)guaiacol peroxidase,(PPO)polyphenol oxidase,(APX)ascorbate peroxidase,(SOD)superoxide dismutase and(CTA)*** changes lead to initiation of hypersensitive response,by thicken of the leaf lamina,lignification under the leaf surface,blocking to stomatal openings,systematic cell death,generation of reactive oxidative species(ROS),activation of pathogen mediated resistance pathways i.e.,production of salicylic acid and jasmonic *** all the physiological changes in the plant due to viral infection supports the activation of defense mechanism of the plant to combat against viral infection by limiting virus in specific area,followed with the production of barriers for pathogen,accumulation of starch in the leaf and excess production of(ROS).These strategies used by the plant to prevent the spread of viru

关键词： Anti-oxidative enzymes defense mechanism phyto-chemicals viral infection

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

Sliding Mode and PI Controllers for Uncertain Flexible Joint Manipulator

引用

International Journal of Automation and computing 2015年第2期12卷 117-124页

作者： Lilia Zouari Hafedh abid Mohamed abid Computer and Embedded Systems Laboratory National School of Sfax EngineersUniversity of Sfax Laboratory of Sciences and Techniques of Automation (Lab-sta) National School of Sfax EngineersUniversity of Sfax

This paper is dealing with the problem of tracking control for uncertain flexible joint manipulator robots driven by brushless direct current motor(BDCM). Flexibility of joint in the manipulator constitutes one of the most important sources of uncertainties. In order to achieve high performance, all parts of the manipulator including actuator have been modeled. To cancel the tracking error, a hysteresis current controller and speed controllers have been developed. To evaluate the effectiveness of speed controllers, a comparative study between proportional integral(PI) and sliding mode controllers has been performed. Finally, simulation results carried out in the Matlab simulink environment demonstrate the high precision of sliding mode controller compared with PI controller in the presence of uncertainties of joint flexibility.

关键词： Flexible joint manipulator uncertainties proportional integral(PI) controller sliding mode brushless direct current motor.

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

Quantum spin Hall and quantum valley Hall effects in trilayer graphene and their topological structures

引用

Chinese Physics B 2017年第12期26卷 481-490页

作者： Majeed Ur Rehman A A abid ICQD Hefei National Laboratory for Physical Sciences at Microscale Department of Physics University of Science and Technology of China Hefei 230026 China Key Laboratory of Geospace Environment(Chinese Academy of Sciences) Department of Geophysics and Planetary Science University of Science and Technology of China Hefei 230026 China

The present study pertains to the trilayer graphene in the presence of spin orbit coupling to probe the quantum spin/valley Hall effect. The spin Chern-number Cs for energy-bands of trilayer graphene having the essence of intrinsic spin-orbit coupling is analytically calculated. We find that for each valley and spin, Cs is three times larger in trilayer graphene as compared to single layer graphene. Since the spin Chern-number corresponds to the number of edge states, consequently the trilayer graphene has edge states, three times more in comparison to single layer graphene. We also study the trilayer graphene in the presence of both electric-field and intrinsic spin-orbit coupling and investigate that the trilayer graphene goes through a phase transition from a quantum spin Hall state to a quantum valley Hall state when the strength of the electric field exceeds the intrinsic spin coupling strength. The robustness of the associated topological bulk-state of the trilayer graphene is evaluated by adding various perturbations such as Rashba spin-orbit （RSO） interaction αR, and exchange-magnetization M. In addition, we consider a theoretical model, where only one of the outer layers in trilayer graphene has the essence of intrinsic spin-orbit coupling, while the other two layers have zero intrinsic spin-orbit coupling. Although the first Chern number is non-zero for individual valleys of trilayer graphene in this model, however, we find that the system cannot be regarded as a topological insulator because the system as a whole is not gaped.

关键词： trilayer graphene quantum spin Hall effect topological insulator quantum phase transition

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

Liver parasites:A global endemic and journey from infestation to intervention

引用

World Journal of Gastroenterology 2025年第1期31卷 8-15页

作者： Yumna Shahid Bushra Emman Shahab abid Department of Medicine Section of GastroenterologyAga Khan University HospitalKarachi 75500SindhPakistan Aga Khan Medical College Aga Khan University HospitalKarachi 75500SindhPakistan

Parasites have coexisted with humans throughout history,forming either symbiotic relationships or causing significant morbidity and *** liver is particularly vulnerable to parasitic infections,which can reside in,pass through,or be transported to the liver,leading to severe *** editorial explores various parasites that infect the liver,their clinical implications,and diagnostic considerations,as discussed in the article“Parasites of the liver:A global problem?”.Parasites reach the liver primarily through oral ingestion,mucosal penetration,or the bloodstream,with some larvae even penetrating the *** parasites such as cestodes(Echinococcus),trematodes(Clonorchis,Opisthorchis),nematodes(Ascaris),and protozoa(Entamoeba histolytica)can also cause systemic infections like visceral leishmaniasis,malaria,cryptosporidiosis,and *** infections like clonorchiasis and opisthorchiasis are linked to persistent hepatobiliary inflammation,potentially progressing to cholangiocarcinoma,a fatal bile duct cancer,particularly prevalent in Southeast *** global nature of liver parasite infestations is alarming,with hundreds of millions affected ***,control over treatment quality remains *** the significant public health threat posed by these parasites,international medical organizations must prioritize improved diagnosis,treatment,and preventive *** educational efforts and enhancing healthcare provider training are critical steps toward mitigating the global impact of parasitic liver diseases.

关键词： Liver flukes Nematodes Cestodes Trematodes Protozoa Parasites

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

Selective catalytic reduction of NO by NH3 on cerium modified faujasite zeolite prepared from aluminum scraps and industrial metasilicate

引用

Journal of Rare Earths 2020年第3期38卷 250-256页

作者： Rahma abid Gerard Delahay Hassib Tounsi Laboratory of Advanced Materials National School of Engineers of SfaxUniversity of SfaxTunisia Institut Charles Gerhardt ENSCM"Advanced Materials for Health and Catalysis"240 Av Professor Emile Jeanbrau34296 MontpellierFrance

This work was devoted to the study of the selective catalytic reduction of NO by NH3 on calcined and hydrothermal treated cerium loaded zeolite *** parent faujasite zeolite Na-F(Si/Al=1.32 and SBET=749 m^2/g) used as support for the preparation of the catalysts was obtained from industrial sodium metasilicate and aluminum *** expected,the NO conversion increases with increasing the percentage of cerium in the structure of the faujasite *** NO conversion into N2 is reached at 400℃at a space velocity of 250 000 h^-*** high conversion is due to the redox shift between Ce^3+/Ce^4+and the strong acid sites related to the rare earth present in the framework that is the key in SCR of NO ***,the highest loaded cerium catalyst retains almost its activity after hydrothermal treatment at 850℃.This higher loading is desirable for both activity and stability provided that two stages of preparation are used to put the Ce ions in the sodalite cages.

关键词： Aluminum scraps Ce-Y NH3-SCR Hydrothermal stability

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

Complex Network Formation and Analysis of Online Social Media Systems

引用

Computer Modeling in Engineering & Sciences 2022年第3期130卷 1737-1750页

作者： Hafiz abid Mahmood Malik Faculty of Computer Studies Arab Open UniversityA’aliKingdom of Bahrain

To discover and identify the influential nodes in any complex network has been an important *** is a significant factor in order to control over the *** control on a network,any information can be spread and stopped in a short span of *** targets can be achieved,since network of information can be extended and as well ***,information spread and community formation have become one of the most crucial issues in the world of SNA(Social Network Analysis).In this work,the complex network of twitter social network has been formalized and results are *** this purpose,different network metrics have been *** of the network is provided in its original form and then filter out(different percentages)from the network to eliminate the less impacting nodes and edges for better *** network is analyzed according to different centrality measures,like edge-betweenness,betweenness centrality,closeness centrality and eigenvector *** nodes are detected and their impact is observed on the *** communities are analyzed in terms of network coverage considering theMinimum Spanning Tree,shortest path distribution and network *** is found that these are the very effective ways to find influential and central nodes from such big social networks like Facebook,Instagram,Twitter,LinkedIn,etc.

关键词： Complex network data extraction nodes and edges network visualization social media network main hubs centrality measures

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

Electrogastrography: Poor correlation with antro-duodenal manometry and doubtful clinical usefulness in adults

引用

World Journal of Gastroenterology 2007年第38期13卷 5101-5107页

作者： Shahab abid Greger Lindberg Karolinska Institutet Department of Medicine Division of Gastroenterology and Hepatology Karolinska University Hospital Huddinge Stockholm 14186 Sweden

AIM: To investigate if there is a correlation between electrical activity measured by electrogastrography (EGG) and contractile activity of the stomach as measured by antroduodenal manometry (ADM). We also studied whether the underlying motility disorder could be predicted from EGG parameters. METHODS: We compared 21 parameters measured from EGG with 8 parameters measured from ADM. The ability of EGG to identify the underlying diagnosis was tested by comparing EGG parameters for each diagnosis group against other patients. The study comprised recordings from 148 patients and 125 females. Their median age was 45 (range 17-76) years. RESULTS: We found few and weak correlations between EGG and ADM. Specifically the correlation between parameters reflecting the response to meal was poor (r = -0.07, P = 0.39). The discriminatory power of EGG for underlying motility disorder was also low. Patients with slow transit constipation (STC) showed a lower postprandial power in normogastric (3.7 ± 0.5 vs 4.0 ± 0.5) and tachygastric (3.5 ± 0.4 vs 3.7 ± 0.4) regions, a lower percentage of time with normogastria [87.2 (56.5-100)% vs 95.7 (0-100)%], and a higher percentage of time with tachygastria [9.3 (0-33)% vs 3.5 (0-100)%] and bradygastria [1.8 (0-20)% vs 0 (0-17.1)%]. Patients with irritable bowel syndrome had a higher percentage of time with normogastria [96.5 (62.5-100)% vs 93.3 (0-100)%] and a less unstable dominant frequency as measured by the instability coefficient [15 (3-77) vs 24 (2-72)]. CONCLUSION: EGG and ADM seem to measure different aspects of gastric motor activity but cannot show a spatial correlation. The diagnostic value of EGG is poor, but EGG may have some value for the identification of patients with STC.

关键词： Antroduodenal manometry Correlation Diagnostic use Electrogastrography Functional bowel disorders Physiopathology

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 New Algorithm for a Condenser Design for Large-Scale Nuclear Power Plants in Tropical Region

引用

Journal of Thermal Science 2020年第5期29卷 1370-1389页

作者： KHAN abid Hossain ISLAM Md.Shafiqul Department of Industrial and Production Engineering Jashore University of Science and TechnologyJashore 7408Bangladesh Department of Nuclear Engineering University of DhakaDhaka 1000Bangladesh

This work presents a new velocity search algorithm for designing a condenser of a 1200 MWe large-scale nuclear power plant situated in tropical *** this,the condenser pressure was considered in the range of 7.5-15 kPa while its tube inner diameter was taken as 28 mm with 1 mm tube wall *** longitudinal and transverse condensers with multiple shell tanks and varied shell tank lengths from 8-14 m have been considered in this *** different tertiary coolant temperature rises were chosen as 4°C,8°C and 12°C by considering tropical region average reservoir water temperature range of 28°C to 32°C during *** of tertiary coolant was kept within 0.75-1.5 m/s to ensure sufficient turbulence to avoid erosion-corrosion of the *** simulation has been employed to obtain tube-side pressure drop and convection heat transfer coefficient directly from tertiary coolant inlet velocity using κ-ω turbulent flow model.A new iterative“Velocity-search algorithm”has been developed that focuses on finding the correct tertiary coolant velocity instead of overall heat transfer *** revealed that velocity-search algorithm yielded very close to the important physical and thermal parameters of condenser compared to the existing design data in large scale nuclear power ***-search algorithm has given less number of condenser design physical parameters that meets the velocity acceptance criteria for longitudinal condenser compared to the transverse ***,velocity-search algorithm is found to be more reliable,robust,and consistent for condenser design compared to the conventional design algorithm used in Log-Mean Temperature Difference method.

关键词： nuclear power plant vacuum condenser velocity-search algorithm tropical region

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

Film Flow of Nano-Micropolar Fluid with Dissipation Effect

引用

Computer Modeling in Engineering & Sciences 2024年第9期140卷 2487-2512页

作者： Abuzar abid Siddiqui Mustafa Turkyilmazoglu Department of Basic Sciences&Humanities Faculty of Engineering&TechnologyBahauddin Zakariya UniversityMultanPakistan Department of Mathematics Hacettepe UniversityAnkaraTürkiye Department of Medical Research China Medical University HospitalChina Medical UniversityTaichungTaiwanChina

The physical problem of the thin film flow of a micropolar fluid over a dynamic and inclined substrate under the influence of gravitational and thermal forces in the presence of nanoparticles is *** different types of nanoparticle samples are accounted for in this current study,namely gold Au,silver Ag,molybdenum disulfide MoS_(2),aluminum oxide Al_(2)O_(3),and silicon dioxide SiO_(2).Blood,a micropolar fluid,serves as the common base *** exact closed-form solution for this problem is derived for the first time in the *** results are particularly validated against those for the Newtonian fluid and show excellent *** was found that increasing values of the spin boundary condition and micropolarity lead to a reduction in both the thermal and momentum boundary layers.A quantitative decay in the Nusselt number for a micropolar fluid,as compared to a Newtonian one for all the tested nanoparticles,is *** and silver nanoparticles(i)intensify in the flow parameter as the concentration of nanoparticles increases(ii)yield a higher thermal transfer rate,whereas molybdenum disulfide,aluminum oxide,and silicon dioxide exhibit a converse attitude for both Newtonian and micropolar *** reduction in film thickness for fluid comprising gold particles,as compared to the rest of the nanoparticles,is remarkable.

关键词： Thin film flow micropolar fluid nanoparticles molybdenum disulfide inclined substrate

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 different catalysts and growth temperature on the photoluminescence properties of zinc silicate nanostructures grown via vapor-liquid-solid method

引用

Chinese Physics B 2022年第5期31卷 657-665页

作者： Ghfoor Muhammad Imran Murtaza Rehan abid Naeem Ahmad Department of Physics International Islamic UniversityIslamabad 44000Pakistan

We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts significantly influence the growth rate which in turn has an impact on the structure and hence the photoluminescence of the prepared zinc silicate ***_(2)SiO_(4) has a wide bandgap of about 5.5 eV and in its pure form,it does not emit in visible region due to its inner shell electronic transitions between the 3 d5 energy ***,the incorporation of different catalysts(Sn,Ag and Mn)at different growth temperatures into the Zn_(2)SiO_(4) crystal growth kinetics provides wide visible spectral range of photoluminescence(PL)*** analysis shows broad multi-band spectrum in the visible region and distinct colors(red,yellow,green,blue,cyan and violet)are obtained depending on the crystalline structure of the prepared *** allowed transitions due to the effect of different catalysts on zinc silicate lattice offer a huge cross-section of absorption that generates strong *** correlation between the structural and optical properties of the synthesized nanostructures is discussed in *** synthesized photoluminescent nanostructures have potential applications in solidstate lighting and display devices.

关键词： nanostructures vapor-liquid-solid growth mode photoluminescence spectra fluorescence microscopy

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：