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WSV 2019: The First Committee Meeting of the World Society for Virology

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Virologica Sinica 2020年第2期35卷 248-252页

作者： ahmed S.abdel-moneim Matthew D.Moore Mahmoud M.Naguib Jesus L.Romalde Maria Soderlund-Venermo Department of Microbiology College of MedicineTaif UniversityAl-Taif 21944Saudi Arabia Department of Virology.Faculty of Veterinary Medicine Beni-Suef UniversityBeni-Suef 62511Egypt Department of Food Science University of MassachusettsAmherstMA 01003USA National Laboratory for Veterinary Quality Control on Poultry Production Animal Health Research InstituteGiza 12618Egypt Department of Medical Biochemistry and Microbiology Zoonosis Science CenterUppsala UniversityUppsala 75237Sweden Department of Microbiology and Parasitology CIBUSFaculty of BiologyUniversidade de Santiago de CompostelaSantiago de Compostela 15782.Spain Department of Virology University of HelsinkiHelsinki 00014Finland

The World Society for Virology(WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct research of viruses that affect humans, other animals, plants, and other organisms. One of the objectives of WSV is to connect virologists worldwide and support collaboration. Fulfilling this objective, virologists from fourteen countries in North America,Europe, Africa, Asia, and the Middle East met on 25–27 th August 2019 in Stockholm, Sweden at the Karolinska University Hospital for the first Committee Meeting of WSV. This meeting included compelling keynote and honorary speeches and a series of 18 scientific talks were given encompassing a diverse array of subjects within virology. Followed by the scientific session, a business session was held where multiple aspects and next steps of the society were discussed and charted out.

关键词： World steps session

Encoderless Five-phase PMa-SynRM Drive System Based on Robust Torque-speed Estimator with Super-twisting Sliding Mode Control

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 54-62页

作者： Ghada A.abdel aziz Rehan Ali Khan Power Electronics and Energy Conversion Department Electronics Research InstituteCairo11843Egypt Department of Electrical Engineering University of Science&TechnologyBannu28100Pakistan IEEE

In this paper,a robust torque speed estimator(RTSE)for linear parameter changing(LPC)system is proposed and designed for an encoderless five-phase permanent magnet assisted synchronous reluctance motor(5-phase PMa-SynRM).This estimator is utilized for estimating the rotor speed and the load torque as well as can solve the speed sensor fault problem,as the feedback speed information is obtained directly from the virtual *** addition,this technique is able to enhance the 5-phase PMa-SynRM performance by estimating the load torque for the real time *** stability analysis of the proposed estimator is performed via Schur complement along with Lyapunov ***,for improving the 5-phase PMa-SynRM performance,five super-twisting sliding mode controllers(ST-SMCs)are employed with providing a robust response without the impacts of high chattering problem.A super-twisting sliding mode speed controller(ST-SMSC)is employed for controlling the PMa-SynRM rotor speed,and four super-twisting sliding mode current controllers(ST-SMCCs)are employed for controlling the 5-phase PMa-SynRM *** stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed RTSE and the ST-SMSC with ST-SMCCs approach for a 750-W 5-phase PMa-SynRM under load disturbance,parameters variations,single open-phase fault,and adjacent two-phase open circuit fault conditions.

关键词： Five-phase permanent magnet assisted synchronous reluctance motor Encoderless control Supertwisting sliding mode control Torque-speed estimator

Investigation on the mechanical properties of sintered porous copper compacts

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China Particuology 2007年第6期5卷 391-394页

作者： Yasser M.Z. ahmed Mohamed I. Riad ahmed I. Zaky Mohammed abdel-aziz Mohamed M.H. Shalabi Central Metallurgical Research and Development Institute CMRDI El-Felzat Street El-Tabbin P.O. Box 87 Helwan Cairo Egypt

In line with recent attention on porous metals having low and medium porosities in the range of 20-50%, this paper studies the effect of porosity on the mechanical properties of sintered copper compacts. Experiments were designed to investigate the effect of porosity, applied stress and sliding velocity on the wear rate of copper compacts, leading to the finding that the effects of both porosity and applied stress of the wear test on the wear rate are approximately similar and higher than that of sliding velocity. The investigation concerning the effect of porosity on compressive strength indicated that the stress-strain curve of high-porosity compact exhibited identifiable ultimate strength points, though low-porosity compact showed distinct stages of elastic plastic behavior.

关键词： Porous copper Wear rate Compressive strength Experimental design technique

Adaptive Gain Tuning Rule for Nonlinear Sliding-mode Speed Control of Encoderless Three-phase Permanent Magnet Assisted Synchronous Motor

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中国电工技术学会电机与系统学报(英文) 2023年第3期7卷 301-310页

作者： Ghada A.abdel aziz Rehan Ali Khan IEEE Power Electronics and Energy Conversion Department Electronics Research InstituteCairo 11843Egypt Department of Electrical Engineering University of Science&TechnologyBannuPakistan.

In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous reluctance motor(PMa-Syn RM) with considering the parameter uncertainties. A nonlinear sliding surface whose parameters are altering with time is designed at first. The proposed NSMSC can minimize the settling time without any overshoot via utilizing a low damping ratio at starting along with a high damping ratio as the output approaches the target set-point. In addition, it eliminates the problem of the singularity with the upper bound of an uncertain term that is hard to be measured practically as well as ensures a rapid convergence in finite time, through employing a simple adaptation law. Moreover, for enhancing the system efficiency throughout the constant torque region, the control system utilizes the maximum torque per ampere technique. The nonlinear sliding surface stability is assured via employing Lyapunov stability theory. Furthermore, a simple sliding mode estimator is employed for estimating the system uncertainties. The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed speed estimation and the NSMSC approach for a 1.1-k W PMa-Syn RM under different speed references, electrical and mechanical parameters disparities, and load disturbance conditions.

关键词： Permanent magnet assisted synchronous reluctance motor Nonlinear sliding mode speed control Speed estimation Parameter uncertainties Sliding mode estimator

Green-synthetized selenium nanoparticles using berberine as a promising anticancer agent

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Journal of Integrative Medicine 2022年第1期20卷 65-72页

作者： Mohamed S.Othman Sofian T.Obeidat Amal H.Al-Bagawi Mohamed A.Fareid Alaa Fehaid ahmed E.abdel moneim Basic Sciences Department Deanship of Preparatory YearUniversity ofHa'ilHail 2240Saudi Arabia Faculty of Biotechnology October University for Modem Science and ArtsGiza 12451Egypt Chemistry Department Faculty of ScienceUniversity of Ha%Hail 2240Saudi Arabia Department of Botany and Microbiology Faculty of ScienceAl-Azhar UniversityCairo 35527Egypt Forensic Medicine and Toxicology Department Faculty of Veterinary MedicineMansoura UniversityDakahlia 35516Egypt Zoology and Entomology Department Faculty of ScienceHelwan UniversityCairo 11795Egypt

Objective: The chemo-preventative and therapeutic properties of selenium nanoparticles(Se NPs) have been documented over recent decades and suggest the potential uses of Se NPs in medicine. Biogenic Se NPs have higher biocompatibility and stability than chemically synthesized nanoparticles, which enhances their medical applications, especially in the field of cancer therapy. This study evaluated the potential of green-synthetized Se NPs by using berberine(Ber) as an antitumor agent and elucidated the mechanism by which these molecules combat Ehrlich solid tumors(ESTs).Methods: Se NPs containing Ber(Se NPs-Ber) were synthesized using Ber and Na2 Se O3 and characterized with Fourier transform infrared spectroscopy. Sixty male Swiss albino mice were then acclimatized for one week, injected with Ehrlich ascites tumor cells, and divided into four groups: EST, EST + cisplatin(5 mg/kg), EST + Ber(20 mg/kg), and EST + Se NPs-Ber(0.5 mg/kg). At the end of a 16-day observation period, 12 mice from each group were euthanized to analyze differences in the body weight, tumor size,gene expression, and oxidative stress markers in the four groups. Three mice from each group were kept alive to compare the survival ***: Treatment with Se NPs-Ber significantly improved the survival rate and decreased the body weight and tumor size, compared to the EST group. Se NPs-Ber reduced oxidative stress in tumor tissue,as indicated by a decrease in the lipid peroxidation and nitric oxide levels and an increase in the glutathione levels. Moreover, Se NPs-Ber activated an apoptotic cascade in the tumor cells by downregulating the B-cell lymphoma 2(Bcl-2) expression rate and upregulating the Bcl-2-associated X protein and caspase-3 expression rates. Se NPs-Ber also considerably improved the histopathological alterations in the developed tumor tissue, compared to the EST ***: Our study provides a new insight into the potential role of green-synthesized Se NPs by using Ber as

关键词： Selenium nanoparticles Berberine Ehrlich solid tumor Oxidative stress Apoptosis

The use of carbon nanomaterials in membrane distillation membranes:a review

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Frontiers of Chemical Science and Engineering 2021年第4期15卷 755-774页

作者： Sebastian Leaper ahmed abdel-Karim Patricia Gorgojo Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterManchesterM139PLUK Water Pollution Research Department National Research CentreGiza 12622Egypt

Membrane distillation(MD)is a thermal-based separation technique with the potential to treat a wide range of water types for various applications and *** challenges remain however,which prevent it from becoming commercially widespread including moderate permeate flux,decline in separation performance over time due to pore wetting and high thermal energy ***,its attractive characteristics such as high rejection(ca.100%)of nonvolatile species,its ability to treat highly saline solutions under low operating pressures(typically atmospheric)as well as its ability to operate at low temperatures,enabling waste-heat integration,continue to drive research interests *** particular interest is the class of carbon-based nanomaterials which includes graphene and carbon nanotubes,whose wide range of properties have been exploited in an attempt to overcome the technical challenges that MD *** low dimensional materials exhibit properties such as high specific surface area,high strength,tuneable hydrophobicity,enhanced vapour transport,high thermal and electrical conductivity and *** use in MD has resulted in improved membrane performance characteristics like increased permeability and reduced fouling *** have also enabled novel membrane capabilities such as in-situ fouling detection and localised heat *** this review we provide a brief introduction to MD and describe key membrane characteristics and fabrication *** then give an account of the various uses of carbon nanomaterials for MD applications,focussing on polymeric membrane *** research directions based on the findings are also suggested.

关键词： carbon nanomaterials graphene membrane distillation desalination carbon nanotubes

A toughness based deformation limit for X- and K-joints under brace axial tension

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 345-362页

作者： Bo GU Xudong QIAN aziz ahmed Department of Civil and Environmental Engineering National University of Singapore 1 Engineering Drive 2 Singapore 117576 Singapore

This study reports a deformation limit for the initiation of ductile fracture failure in fatigue-cracked circular hollow section （CHS） X- and K-joints subjected to brace axial tension. The proposed approach sets the deformation limit as the numerically computed crack driving force in a fatigue crack at the hot-spot location in the tubular joint reaches the material fracture toughness measured from standard fracture specimens. The calibration of the numerical procedure predicates on reported numerical computations on the crack driving force and previously published verification study against large-scale CHS X-joints with fatigue generated surface cracks. The development of the deformation limit includes a normalization procedure, which covers a wide range of the geometric parameters and material toughness levels. The lower-bound deformation limits thus developed follow a linear relationship with respect to the crack-depth ratio for both X- and K-joints. Comparison of the predicated deformation limit against experimental on cracked tubular X- and K- joints demonstrates the conservative nature of the proposed deformation limit. The proposed deformation limit, when extrapolated to a zero crack depth, provides an estimate on the deformation limits for intact X- and K-joints under brace axial loads.

关键词： circular hollow section (CHS) tubular joint fracture failure deformation limit J-integral

Stem cells:Sources, and regenerative therapies in dental research and practice

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World Journal of Stem Cells 2015年第7期7卷 1047-1053页

作者： Lobna abdel aziz Aly Oral and Maxillofacial Surgery Faculty of DentistryFuture University

Stem cells are considered to be among the principle scientific breakthroughs of the twentieth century for the future of medicine, and considered to be an important weapon to fight against diseases, particularly those that have resisted the efforts of science for a long time. Human dental tissues have limited potentials to regenerate but the discovery of dental stem cells have developed new and surprising scenario in regenerative dentistry. Stem cell treatments are one example of thepossibility using adult cells sourced from patients' own bodies' means that it can be expected that in the near future such treatments may become routine at dental practices. The hope is that it will become possible to regenerate bone and dental tissues including the periodontal ligament, dental pulp and enamel, and that the creation of new teeth may also become feasible. In view of this possibility of achieving restoration with regenerative medicine, it can be considered that a new era of dentistry is beginning. Thus the aim of this review is to give dental professionals a brief overview of different stem cells sources and the latest findings and their implications for improving oral health and treating certain conditions of the human mouth and face.

关键词： Stem cells Regeneration Dental research

Intestinal protozoa and intestinal helminthic infections among schoolchildren in Central Sudan

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Asian Pacific Journal of Tropical Medicine 2010年第4期3卷 292-293页

作者： abdel-aziz M.ahmed Azam A.Afifi Elfatih M.Malik Ishag Adam University of Khartoum Sudan Preventive Medicine Federal Ministry of HealthSudan

Objective:To determine the prevalence of intestinal parasitic infections and soil-transmitted helminths(STHs) among primary schoolchildren in El dhayga,Central ***:In this cross-sectional study,three fresh faecal samples were collected from each child,which were examined by direct wet mount,brine flotation,formalin-ether and Kato-Katz *** intensity of each STH infection was expressed as the mean of eggs per gram counts of the three ***:In total,142(90.4%) of 157 children harboured at least one type of intestinal *** lumbricoides,Hymenolepis nana,Entamoeba histolytica and Giardia lamblia were the most common parasites found,with prevalence rates of 32.5%,30.6%,33.1%and 19.7%,*** of these 157 children,29(18.5%) harboured more than two intestinal parasitic *** cases of Schistosoma mansoni or Enterobius vermicularis were identified. Conclusions:The study demonstrates significant burden of intestinal protozoa and STH infections in this part of Sudan and highlights the need for preventive and intervention measures.

关键词： Schoolchildern Helminthes Intestinal Protozoa Sudan