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Two Bioinspired Mobile Manipulators with Rolling Locomotion

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Journal of Bionic Engineering 2016年第1期13卷 48-58页

作者： Saber Mahboubi Heydarabad Mir Masoud Seyyed Fakhrabadi Steve Davis samia Nefti-Meziani School of Computing Science & Engineering University of Salford Manchester The Crescent M5 4WT UK School of Mechanical Engineering College of Engineering University of Tehran Tehran Iran

This paper deals with two novel structures for mobile robots. The original inspiration of the robots comes from a sala- mander and a specific kind of spiders. Our robots have some especial moving capabilities causing to increase the robot ma- neuverability. Indeed, the capability of rolling motion is added to ordinary quadruped robots. This capability causes increment in maneuvering of the robots. Manipulators can be embedded into the robots to add the ability of transferring materials into the shell and conducting some tasks such as repairing. In this paper, after analysis of motion principles of the rolling robots, their dynanlic equations are derived. Different simulations of two bioinspired mobile robots are presented in order to scrutinize various capabilities of the proposed designs. Walking capabilities of the robots and their advantages are discussed in detail. The comprehensive simulation results of the robots in various motion modes are presented. Finally the first prototype is introduced to verify the motion mechanisms.

关键词： bionics rolling robot quadruped robot Lagrange equations

Electro-catalyzed multicomponent transformation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one to 1,4-dihydropyrano[2,3-c]pyrazole derivatives in green medium

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Chinese Chemical Letters 2015年第8期26卷 973-976页

作者： Zahra Vafajoo Nourallah Hazeri Malek taher Maghsoodlou Hojat Veisi Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan Department of Chemistry Payame Noor University

An efficient and convenient synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives is described,using the electrogenerated anion of ethanol as the base in the presence of sodium bromide as an supporting electrolyte in a one-pot, three component condensation of malononitrile, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5（4H）-one. The reaction is carried out in an undivided cell containing an iron electrode as the cathode and a graphite electrode as the anode, at a constant current at room temperature.

关键词： pyrazole catalyzed aldehydes aromatic condensation convenient electrolyte graphite cathode anode

Complex role of autophagy in regulation of hepatic lipid andlipoprotein metabolism

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The Journal of Biomedical Research 2017年第5期31卷 377-385页

作者： Mostafa Zamani Jennifer taher Khosrow Adeli Molecular Structure and Function Research Institute The Hospital for Sick Children Toronto ON M5G 1X8 Canada Department of Laboratory Medicine and Pathobiology University of Toronto ON M5G OA4 Canada Department of Biochemistry University of Toronto ON M5G OA4 Canada.

Discovering new therapeutic interventions to treat lipid and lipoprotein disorders is of great interest and the discovery of autophagy as a regulator of lipid metabolism has opened up new avenues for targeting modulators of this pathway. Autophagy is a degradative process that targets cellular components to the lysosome and recent studies have indicated a role for autophagy in regulating hepatic lipid metabolism(known as lipophagy) as well as lipoprotein assembly. Autophagy directly targets apolipoprotein B-100(apoB100), the structural protein component of very lowdensity lipoproteins(VLDLs), and further targets lipid droplets(LDs), the cellular storage for neutral *** thus plays a complex and dual role in VLDL particle assembly by regulating apoB 100 degradation as well as aiding the maturation of VLDL particles by hydrolyzing lipid from LDs. The purpose of this article is to review our current understanding of molecular and cellular mechanisms mediating authophagic control of hepatic lipid biogenesis and VLDL production as well as dysregulation in insulin resistance and dyslipidemia.

关键词： autophagy lipophagy lipid droplets apolipoprotein B-100 VLDL dyslipidemia hepatic steatosis

Numerical Investigation of Rotating Stall in Centrifugal Compressor with Vaned and Vaneless Diffuser

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Journal of Thermal Science 2015年第4期24卷 323-333页

作者： taher Halawa Mohamed Alqaradawi Mohamed S.Gadala Ibrahim Shahin Osama Badr Mechanical Engineering Department UBC-University of British ColumbiaVancouverB.C.Canada Mechanical Engineering Department Cairo University Mechanical & Industrial Engineering Department Qatar University Mechanical Engineering Department Abu Dhabi University Mechanical and Industrial Engineering Department Qatar UniversityDohaQatar Mechanical Engineering Department Benha University Mechanical Engineering Department British University

This study presents a numerical simulation of the stall and surge in a centrifugal compressor and presents a description of the stall development in two different *** first case is for a compressor with vaneless diffuser and the second is for a compressor with vaned diffuser of the vane island *** main aim of this study is to compare the flow characteristics and behavior for the two compressors near the surge operating condition and provide further understanding of the diffuser role when back flow occurs at *** showed that for a location near the diffuser entrance,the amplitude of the static pressure fluctuations for the vaneless diffuser case is higher than that for the vaned diffuser case near surge *** pressure fluctuations in the case of the vaneless diffuser appear with a gradual decrease of the mean pressure value as a part of the surge *** for the case of the vaned diffuser,the pressure drop during surge occurs faster than the case of the vaneless ***,results indicated that during surge in the case of vaneless diffuser,there is a region with low velocity and back flow that appears as a layer connecting all impeller passages near shroud surface and this layer develops in size with *** the other hand,for the case of vaned diffuser during surge,the low velocity regions appear in random locations in some passages and these regions expand with time towards the shroud *** showed that during stall,the impeller passages are exposed to identical impact from stall cells in the case of vaneless diffuser while the stall effect varies from passage to another in the case of the vaned diffuser.

关键词： centrifugal compressors rotating stall surge vaneless diffuser vaned diffuser

Decreased apoptosis in advanced-stage/high-grade hepatocellular carcinoma complicating chronic hepatitis C is mediated through the downregulation of p21 ras

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Chinese Journal of Cancer Research 2013年第3期25卷 281-288页

作者： Nahed Baddour Ebtehal Farrag Ahmed Zeid Essam Bedewy Yousry taher Departments of Pathology Alexandria Egypt Departments of Hepatobiliary Unit Internal MedicineAlexandria Egypt Departments of Tropical Medicine of the Alexandria Faculty of Medicine Alexandria Egypt

Objective and background： Although p21 ras has been reported to be upregulated in hepatocellular carcinoma complicating chronic hepatitis C type I, p21 ras has a different role in advanced stages, as it has been found to be downregulated. The goal of this study was to investigate the status of p21 ras in early-stage/low-grade and late-stage/high-grade hepatocellular carcinoma and its possible link to apoptosis. Material and methods： Thirty-five cases each of chronic HCV hepatitis type 4 （group I） and cirrhosis with hepatocellular carcinoma （HCC） complicating chronic HCV hepatitis （groups Ⅱ and Ⅲ） were immunohistochemically evaluated using a p21 ras polyclonal antibody. The apoptotic index was determined in histologic sections using the terminal deoxynncleotidyl transferase-mediated d-UTP biotin nick end labeling （TUNEL） assay. Results： Significant differences （P=0.001） were detected in p21 ras protein expression between the three groups. A near 2-fold increase in p21 ras staining was observed in the cirrhotic cases compared to the hepatitis cases, and p21 ras expression was decreased in the HCC group, p21 ras expression correlated with stage （r=0.64, P--0.001） and grade （r=-0.65, P=0.001） in the HCC group and grade in the HCV group （r=0.44, P=0.008）. Both p21 ras expression and TUNEL-LI were significantly lower in large HCCs compared to small HCCs （P=0.01 each）. The TUNEL values were negatively correlated with stage in the HCC group （r=-0.85, P=0.001）. The TUNEL values were also negatively correlated with grade in both the HCV and HCC groups （r=0.89, P=0.001 and r=0.53, P=0.001, respectively）. The p21 ras scores were significantly correlated with the TUNEL-LI values in the HCC group （r=0.63, P=0.001） and HCV group （r=0.88, P=0.001）. Conclusions： p21 ras acts as an initiator in HCC complicating type 4 chronic HCV and is downregulated with HCC progression, which most likely promotes tumor cell survival because it facilitates the downregulation of apoptosis with tumor

关键词： p21 ras terminal deoxynucleotidyl transferase-mediated d-UTP biotin nick end labeling (TUNEL) apoptosis HCV type 4 hepatocellular carcinoma

Improvement in corrosion resistance of magnesium coating with cerium treatment

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Rare Metals 2009年第3期28卷 277-283页

作者： samia Ben Hassen Latifa Bousselmi Patrice Berot El Mustafa Rezrazi Ezzeddine Triki Unité de Recherche Corrosion & Protection des Métalliques ENITBP 37Tunis-BelvédèreTunisia Institut UTINAM CNRS UMR 6213Université de Franche-Comté16 route de Gray 25030 Besanon CedexFrance Laboratoire Traitement et Recyclage des Eaux CERTEBorj CedriaTunisia

Corrosion protection afforded by a magnesium coating treated in cerium salt solution on steel substrate was investigated using open circuit potential, polarization curves, and electrochemical impedance spectroscopy （EIS） in 0.005 M sodium chloride solution （NaCl）. The morphology of the surface was characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, and X-ray diffraction （XRD）. The cerium treated coating was obtained by immersion in CeCl3 solution. The results showed that the corrosion resistance of the treated magnesium coating was improved. The corrosion potential of the treated coating was found to be nobler than that of the untreated magnesium coating and the corrosion current decreased significantly. Impedance results showed that the cerium treatment increased corrosion protection. The improvement of anti-corrosion properties was attributed to the formation of cerium oxides and hydroxides that gave rise to a physical barrier effect.

关键词： magnesium coating cerium corrosion protection impedance spectroscopy

Governance interactions of spatial data infrastructures: an agent-based modelling approach

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International Journal of Digital Earth 2021年第6期14卷 696-713页

作者： Jaap-Willem Sjoukema Jalal samia Arnold K.Bregt Joep Crompvoets Laboratory of Geo-Information Science and Remote Sensing Wageningen University&ResearchWageningenThe Netherlands KU Leuven Public Governance Institute LeuvenBelgium Department of Geography and Urban Planning University of MazandaranBabolsarIran

In order to facilitate and coordinate spatial data sharing and exchange,many organisations have developed spatial data infrastructures(SDIs).SDI governance plays a pivotal role in the development and evolution of an SDI,but as SDIs are complex adaptive systems,governing is a *** research therefore proposes a complexity perspective to SDI governance by exploring the use of agent-based modelling to simulate and examine SDI governance *** this agent-based simulation,we examine interactions between SDI stakeholders,data availability and the effects of different governance styles(hierarchical,network and laissez-faire governance)and budget *** simulation shows that it is possible to mimic SDI governance dynamics through agent-based *** running different scenarios,it appears that a network approach is more successful compared to a hierarchical or laissez-faire *** validation shows that overall the results of the simulation are credible and insightful,although improvements can be made to make the model more *** agent-based modelling,SDI governance becomes more tangible and visible,which facilitates discussion and ***-based modelling therefore appears to be a helpful new approach in a better understanding of the complexities and dynamics of SDI governance.

关键词： Governance spatial data infrastructure(SDI) agentbased modelling funding models complex adaptive systems

Electrocatalytic determination of L-cysteine using a modified carbon nanotube paste electrode:Application to the analysis of some real samples

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Chinese Chemical Letters 2012年第8期23卷 981-984页

作者： Malihe Ahmadipour Mohammad Ali taher Hadi Beitollahi Rahman Hosseinzadeh Department of Chemistry Shahid Bahonar University of KermanP.O.Box 76175-133KermanIran Young Researchers Society Shahid Bahonar University of KermanP.O.Box 76175-133KermanIran Environment Department Research Institute of Environmental SciencesInternational Center for ScienceHigh Technology&Environmental SciencesKermanIran Department of Organic Chemistry Faculty of ChemistryUniversity of MazandaranBabolsarIran

The electrooxidation of L-cysteine（L-Cys） was studied using a benzoylferrocene（BF） modified multi-wall carbon nanotube paste electrode（BFCNPE） using cyclic voltammetry（CV）,square wave voltammetry（SWV） and chronoamperometry（CHA）.Under optimum pH in CV the oxidation of L-Cys occurs at a potential about 215 mV less positive than that at the surface of unmodified carbon paste *** catalytic oxidation peak currents were dependent on the L-Cys concentration and a linear calibration curve was obtained in the range 0.7-350.0 mmol/L of L-Cys with SWV *** detection limit（3s） was determined as 0.1 mmol/*** method was also used for the determination of L-Cys in some real samples.

关键词： L-Cysteine Carbon paste electrode Carbon nanotubes Voltammetry

XPS characterization and corrosion resistance of cerium-treated magnesium coatings

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Rare Metals 2011年第4期30卷 368-373页

作者： samia Ben Hassen Latifa Bousselmi Patrice Berot El Mustafa Rezrazi Ezzeddine Triki Unité de Recherche Corrosion & Protection des Métalliques ENITBP 37Tunis-BelvédèreTunisie Institut UTINAM CNRS UMR 6213Université de Franche-Comté16 route de Gray 25030 Besanon CedexFrance Laboratoire Traitement et Recyclage des Eaux CERTEBorj CedriaTunisie

Cerium conversion treatment was applied on magnesium coatings in a solution containing CeC13. The composition ot the cenum conversion layer on magnesium was investigated using X-ray photoelectron spectroscopy （XPS）, It was revealed that the composition predominately consisted of a three-valent state cerium compound with a relative abundance around 90%. Some of Ce^3＋ was oxidized to Ce^4＋. Electrochemical impedance spectroscopy results revealed that the total impedance of cerium-treated samples increased for a short immersion time in NaC1 solution before coating deteriorating. This deterioration was due to the coating porosity increasing and the breakdown of the conversion layer

关键词： cerium compounds magnesium coatings X-ray photoelectron spectroscopy corrosion resistance