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Effect of helicobacter pylori infection on gastric epithelial cell proliferation

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World Journal of Gastroenterology 2000年第3期6卷 442-444页

作者： Gao h Wang JY Shen XZ Liu JJ Shanghai Med Univ Zhongshan Hosp Dept Internal Med Shanghai 200032 Peoples R China

INTRODUCTION helicobacter pylori(***)infection is one ofthe main pathogens of chronic gastritis and duodenalulcer(DU),and it may be considered as a riskfactor in the incidence of gastric *** infection may lead to the anomaly of gastricepithelial cell proliferation which is closely relatedto the development of gastric ***(VacA)is an important virulence andvacA subtype determines the toxic *** to its signal sequence,it can be groupedinto type sla,slb,slc and *** harboringvacAsla are more closely related with digestivediseases and may be the strains with high *** effect of *** infection on

关键词： helicobacter pylori cell proliferation vacAsla strain gastric epithelial cell

Meteorological impacts on evapotranspiration in different climatic zones of pakistan

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Journal of Arid Land 2017年第6期9卷 938-952页

作者： Shahzada ADNAN Kalim ULLAh Azmat h KhAN GAO Shouting Department of Meteorology COMSATS Institute of Information Technology Islamabad 44000 Pakistan pakistan Meteorological Department Islamabad 44000 Pakistan State key Laboratory of Cloud-precipitation physics and SevereStorms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Arid regions are highly vulnerable and sensitive to drought. The crops cultivated in arid zones are at high risk due to the high evapotranspiration and water demands. This study analyzed the changes in seasonal and annual evapotranspiration（ET） during 1951–2016 at 50 meteorological stations located in the extremely arid, arid, and semi-arid zones of pakistan using the penman Monteith（pM） method. The results show that ET is highly sensitive and positively correlated to temperature, solar radiation, and wind speed whereas vapor pressure is negatively correlated to ET. The study also identifies the relationship of ET with the meteorological parameters in different climatic zones of pakistan. The significant trend analysis of precipitation and temperature（maximum and minimum） are conducted at 95% confidence level to determine the behaviors of these parameters in the extremely arid, arid, and semi-arid zones. The mean annual precipitation and annual mean maximum temperature significantly increased by 0.828 mm/a and 0.014℃/a in the arid and extremely arid zones, respectively. The annual mean minimum temperature increased by 0.017℃/a in the extremely arid zone and 0.019℃/a in the arid zone, whereas a significant decrease of 0.007℃/a was observed in the semi-arid zone. This study provides probabilistic future scenarios that would be helpful for policy-makers, agriculturists to plan effective irrigation measures towards the sustainable development in pakistan.

关键词： evapotranspiration meteorological parameters climatic zone penman Monteith method pakistan

Attuned design of demand response program and M-FACTS for relieving congestion in a restructured market environment

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Frontiers in Energy 2015年第3期9卷 282-296页

作者： Y. hAShEMI h. ShAYEGhI B. hAShEMI Technical Engineering Department University of Mohaghegh Ardabili Ardabil *** Iran Network Studies Group Bakhtar Regional Electric Company Arak *** Iran

This paper addresses the attuned use of multi- converter flexible alternative current transmission systems （M-FACTS） devices and demand response （DR） to perform congestion management （CM） in the deregulated environment. The strong control capability of the M- FACTS offers a great potential in solving many of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare （SW） and congestion as network constraint is paid by using concurrently the DR and M-FACTS. A multi-objective problem （MOp） based on the sum of the payments received by the generators for changing their output, the total payment received by DR participants to reduce their load and M-FACTS cost is systematized. For the solution of this problem a nonlinear time-varying evolution （NTVE） based multi-objective particle swarm optimization （MOpSO） style is formed. Fuzzy decision-making （FDM） and technique for order preference by similarity to ideal solution （TOpSIS） approaches are employed for finding the best compromise solution from the set of pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-varying evolution （MOpSO-NTVE）. In a real power system, Azarbaijan regional power system of Iran, comparative analysis of the results obtained from the application of the DR ＆ unified power flow controller （UpFC） and the DR ＆ M-FACTS are presented.

关键词： multi-converter flexible alternative currenttransmission systems (M-FACTS) demand response,

Inverse Analysis of Origin-Destination Matrix for Microscopic Traffic Simulator

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Computer Modeling in Engineering & Sciences 2017年第1期113卷 71-87页

作者： K.Abe h.Fujii S.Yoshimura The University of Tokyo BunkyoTokyoJapan

Microscopic traffic simulations are useful for solving various trafficrelated problems,*** jams and accidents,local and global environmental and energy problems,maintaining mobility in aging societies,and evacuation planning for natural as well as man-made *** origin-destination(OD)matrix is often used as the input to represent traffic demands into traffic *** this study,we propose an indirect method for estimating the OD matrix using a traffic simulator as an internal *** proposed method is designed to output results that are consistent with the input of the *** method consists of the following steps:(1)calculating link traffic volume from the OD matrix,and(2)updating the *** estimated matrix is updated iteratively until it converges to a predefined tolerance *** experiments are then conducted using the proposed method on a grid network and on a representation of an actual road ***,we discuss the characteristics of the proposed method and the non-negative constraint for the traffic volume.

关键词： OD estimation inverse problem traffic simulation Levenberg-Marquardt method iterative method

Analysis of a hand-foot-mouth disease model

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International Journal of Biomathematics 2017年第2期10卷 1-47页

作者： Swarnali Sharma G. p. Samanta Department of MathematicsIndian Institute of Engineering Science and Technology Shibpur Howrah 711103 India

In this paper, we have introduced a six-compartmental epidemic model with hand, foot and mouth disease （hFMD） infection. The total population is divided into six subclasses, namely susceptible, exposed, infective in asymptomatic phase, infective in symptomatic phase, quarantined and recovered class. Some basic properties such as boundedness and non-negativity of solutions are discussed. The basic reproduction number （R0） of the system is obtained using next generation matrix method. Then the deterministic dynamical behaviors of the system are studied. Our study includes the existence and stability analysis of equilibrium points of the system. The sensitivity analysis of our system helps us to find out the parameters of greater interest. Next, we deal with the epidemic model with three controls （two treatment controls with quarantine control）. We show that there exists an optimal control, which is effective in controlling the disease outbreak in a cost effective way. Numerical simulation is presented with the help of MATLAB, which shows tile reliability of our model from the practical point of view.

关键词： hand, foot and mouth disease (hFMD) infection basic reproduction number equilibrium points local and global stability optimal control.

Spread and control of COVID-19:A mathematical model

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第3期13卷 121-148页

作者： O.p.Misra Omprakash Singh Sisodiya School of Mathematics and Allied Sciences Jiwaji University Gwalior 474011Madhya PradeshIndia

A mathematical model is proposed in this paper to study the transmission and control of *** mathematical model is formulated using system of nonlinear ordinary differential *** model includes disease-related parameters such as contact rate,disease-induced death rates,immigration rate and transition rates along with parameters for control measures such as implementation of social distancing practices,isolation and quarantine *** the stability analysis of the model,it is shown that if the social distancing is practiced by the large number of susceptible population,then the disease will not spread,and it may eventually die ***,it is derived from the analysis of the model that if most of the infected populations are isolated or quarantined,then the spread of the disease can be eventually ***,from the analysis of the model,it is observed that if there is constant immigration of asymptomatic infected persons,then the disease will continue to spread and will remain *** controlling the disease,two more parameters,that is,vaccination and testing rates,are introduced in the original mathematical model and from the numerical analysis of this model,it has been shown that the control strategy involving vaccination and testing in combination can have synergistic effect for minimizing the COVID-19 infected cases.

关键词： COVID-19 social distancing isolation quarantine immigration mathematical model

Dynamic Time and Location Information in Ciphertext-policy Attribute-Based Encryption with Multi-Authorization

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Intelligent Automation & Soft Computing 2023年第3期35卷 3801-3813页

作者： p.prathap Nayudu Krovi Raja Sekhar Department of Computer Science and Engineering Koneru Lakshmaiah Education FoundationVaddeswaramAP522502India

Due to the mobility of users in an organization,inclusion of dynamic attributes such as time and location becomes the major challenge in Ciphertext-policy Attribute-Based Encryption(Cp-ABE).By considering this challenge;we focus to present dynamic time and location information in Cp-ABE with ***ﬁrst,along with the set of attributes of the users,their corre-sponding location is also *** is used to encode the latitude and longitude of the user’s ***,decrypt time period and access time period of users are deﬁned using the new time tree(NTT)*** NTT sets the encrypted duration of the encrypted data and the valid access time of the private key on the data user’s private ***,single authorization of attribute authority(AA)is extended as multi authorization for enhancing the effectiveness of key *** results depict that the proposed Cp-ABE achieves better encryption time,decryption time,security level and memory ***,encryption time and decryption time of the proposed Cp-ABE are reduced to 19%and 16%than that of existing Cp-ABE scheme.

关键词： Cp-ABE geohash new time tree(NTT) multi authorization dynamic attribute

Effect of seaweed coating on quality characteristics and shelf life of tomato (Lycopersicon esculentum mill)

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Food Science and human Wellness 2020年第2期9卷 176-183页

作者： Thahira Banu A Sri Ramani p Aswini Murugan School of Sciences Department of Home ScienceThe Gandhigram Rural Institute–(Deemed to be University)Gandhigram624302DindigulTamil NaduIndia

Seaweeds are the natural marine algae which have several properties to act as natural preservatives to extend the shelf life of perishable foods without affecting their quality and causing side *** available and cheap fruits such as tomato are perishable very easily due to its high water *** gel coating is a good choice,easily available and cheap natural preservative abundantly available in the Indian *** present study was undertaken to extend the shelf life of the tomatoes using seaweed gel coating at different *** seaweeds namely Kappaphycus alvarezii(red algae)and Sargassum tenerrimum(brown algae)was selected due to their high gelling *** seaweeds were collected in dry form from Aqua Agri processing Limited,Mana Madurai(SIpCOT)Tamil Nadu,*** seaweed extracts were tested for phytonutrients,antibacterial and anti-fungal activity using standard *** shelf life of seaweed coated tomatoes using different concentrations of the seaweed extract(gel)was *** the results,it is understood that the phytonutrients namely flavonoids,steroids,saponins and tannins are present in both the selected *** and antifungal activity of Kappaphycus alvarezii showed higher inhibition zone than *** against common *** characteristics and shelf life evaluation was based on water loss,texture,ascorbic acid content,juice content,total soluble solids(TSS),total acidity and TSS/total acidity ratio,*** results pointed out that *** was the most effective in maintaining the quality characteristics of tomato fruits and it also supports the fruit quality during storage period than ***,from the results of the study it is concluded that the better quality characteristics and shelf life of tomatoes can be increased by coating seaweed gel and it can be used as a bio preservative in fruit and vegetable preservation.

关键词： Seaweeds preservatives Antibacterial Antifungal phytonutrients Inhibition

Effect of plastic Deformation on Magnetic properties of Fe-40%Ni-2%Mn Austenitic Alloy

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Journal of Iron and Steel Research International 2007年第4期14卷 56-60页

作者： Selva Büyükakka■ h Aktas S Akturk physics Department Nigde UniversityNigde 51100NigdeTurkey physics Department Kirikkale UniversityYahsihan 71450KirikkaleTurkey

The effects of plastic deformation on the magnetic properties of austenite structure in an Fe-40% Ni-2 % Mn alloy is investigated by using Mossbauer spectroscopy and Differential Scanning Calorimetry （DSC） techniques The morphology of the alloy has been obtained by using Scanning Electron Microscopy （SEM）. The magnetic behaviour of austenite state is ferromagnetic. After plastic deformation, a mixed magnetic structure including both paramagnet- ic and ferromagnetic states has been obtained at the room temperature. The volume fraction changes, the effective hyperfine fields of the ferromagnetic austenite phase and isomery shift values have also been determined by Mossbauer spectroscopy. The Curie point （Tc） and the Neel temperature （TN） have been investigated by means of DSC system for non-deformed and deformed Fe-Ni-Mn alloy. The plastic deformation of the alloy reduces the TN and enhances the paramagnetic character of austenitic Fe-Ni-Mn alloy.

关键词： Mossbauer spectroscopy differential scanning calorimetry (DSC) scanning electron microscopy (SEM) plastic deformation magnetically ordered material ferromagnetic austenite