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Antibacterial, antifungal and cytotoxic activity of terrestrial cyanobacterial strains from serbia

science China(Life sciences) 2008年第10期51卷 941-947页

作者： Zorica sVIRCEV Dragana CETOJEVIC-sIMIN Jelica sIMEUNOVIC Maja karaman Dejan sTOJANOVIC Department of Biology and Ecology Faculty of Sciences University of Novi Sad Trg Dositeja Obradovica 2 Novi Sad 21000 Serbia Oncology Institute of Vojvodina Institutski put 4 Sremska Kamenica 21204 Serbia

Cyanobacteria are known to be a rich source of biologically active compounds some of which can have pharmaceutical importance. In this work we present the screening results of cyanobacterial strains for their antibacterial, antifungal, and cytotoxic activity. Cyanobacterial strains were isolated from various soil types in province of Vojvodina and Central serbia, Republic of serbia. The screening included 9 strains of Anabaena and 9 strains of Nostoc. Both, extracellular products (from the culture liquid) and cellular crude lipophilic extracts were tested against 13 bacterial strains and 8 fungal strains. Cytotoxic activity was tested against three human cell lines. Methanol extracts were prepared according to ?stensvik. Antibacterial and antifungal activities were determined measuring inhibition zone, 48 h after inoculation. The cytotoxic activity was determined by sulforhodamine B (sRB) colorimetric assay. Of all cyanobacterial strains tested, 52% showed some antifungal and 41% antibacterial activity. Two out of six tested strains possessed cytotoxic activity. The cytotoxic activity of Anabaena strain s12 was found both in culture liquid and crude cell extract. It occurred specifically between the 21st and 42nd day of cultivation against HeLa and MCF7 cells, but had no activity against cell line derived from a healthy tissue. A high percentage of the active strains among the tested strains justify the effort of screening cyanobacteria that are isolated from terrestrial environments. The most promising strains for the fur- ther study are Anabaena strain s12 which showed strong cytotoxic and antibacterial activity and Ana- baena strain s20 which produces a potent antifungal compound. The future work, besides further screening and chemical identification of the active compounds, should also include the development of culture techniques that would lead to more efficient production of biologically active compounds.

关键词： antibacterial antifungal cyanobacteria cytotoxic screening

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Wetting effects and strength degradation of swelling shale evaluated from multistage triaxial test

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Underground space 2019年第2期4卷 79-97页

作者： Hayder Mohammed salim Al-Maamori M.hesham El Naggar silvana Micic Civil and Environmental Engineering Department The University of Western Ontario1151 Richmond St.LondonOntario N6A 5B9Canada Geotechnical Research Centre Civil and Environmental Engineering DepartmentThe University of Western Ontario1151 Richmond St.LondonOntario N6A 5B9Canada

The multistage triaxial compression test was mainly utilized in this research to investigate the degradation in the strength of swelling shale under different wetting *** samples were tested in four different conditions:(1)under their natural moisture content denoted as intact,and after soaking in,(2)water,(3)polymer solution,and(4)bentonite solution,*** experimental results showed that a considerable decrease in the shale’s strength was noted after soaking in water and the lubricant fluids(LFs).The polymer solution caused the least decrease in the strength compared to other *** envelopes of the tested shale were constructed for intact and soaked *** envelopes showed fair agreement between the single stage and the multistage triaxial compression test results,indicating suitability of the multistage triaxial compression test for the tested swelling shale.

关键词： Multistage Triaxial compression swelling shale strength degradation strength envelopes

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Effective damping of local low frequency oscillations in power systems integrated with bulk PV generation

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Protection and Control of Modern Power systems 2021年第1期6卷 512-524页

作者： Ahmed hesham Abd El-Kareem Mohamed Abd Elhameed Mahmoud M.Elkholy Operation Engineer at New Capital Power Plant New Capital CityEgypt Electrical Power and Machines Department Faculty of EngineeringZagazig UniversityZagazigEgypt

High penetration of renewable sources into conventional power systems results in reduction of system inertia and noticeable low-frequency oscillations (LFOs) in the rotor speed of synchronous generators. In this paper, we propose effective damping of LFOs by incorporating a supplementary damping controller with a photovoltaic (PV) generating station, where the parameters of this controller are coordinated optimally with those of a power system stabilizer (Pss). The proposed method is applied to damp local electromechanical modes by studying a system comprising a synchronous generator and a PV station connected to an infinite bus. The PV station is modeled following the instructions of the Western Electricity Coordinating Council. The problem is modeled as an optimization problem, where the damping ratio of the electromechanical modes is designed as the objective function. Constraints including upper and lower limits of decision parameters and damping ratio of other modes are considered by imposing penalties on the objective function. Different optimization algorithms are used to pursue the optimal design, such as political, improved gray wolves and equilibrium optimizers. The results validate the effectiveness of the proposed controller with Pss in damping local modes of oscillations.

关键词： Low frequency oscillations Damping controller PV WECC

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Impacts of produced water origin on bacterial community structures of activated sludge

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Journal of Environmental sciences 2015年第11期27卷 192-199页

作者： Zhenyu Wang Feng Pan Abd El-Latif hesham Yingxin Gao Yu Zhang Min Yang state Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Key Laboratory for Microorganisms and Functional Molecules College of Life Science Henan Normal University Genetics Department Faculty of Agriculture Assiut University

The purpose of this study was to reveal how activated sludge communities respond to influent quality and indigenous communities by treating two produced waters from different origins in a batch reactor in succession. The community shift and compositions were investigated using Polymerase Chain Reaction–denaturing gradient gel electrophoresis（PCR–DGGE） and further16 s ribosomal DNA（r DNA） clone library analysis. The abundance of targeted genes for polycyclic aromatic hydrocarbon（PAH） degradation, nah Ac/phn Ac and C12O/C23 O, was tracked to define the metabolic ability of the in situ microbial community by Most Probable Number（MPN） PCR. The biosystem performed almost the same for treatment of both produced waters in terms of removals of chemical oxygen demand（COD） and PAHs. sludge communities were closely associated with the respective influent bacterial communities（similarity 〉 60%）, while one sludge clone library was dominated by the Betaproteobacteria（38%） and Bacteriodetes（30%）and the other was dominated by Gammaproteobacteria（52%）. This suggested that different influent and water quality have an effect on sludge community compositions. In addition, the existence of catabolic genes in sludge was consistent with the potential for degradation of PAHs in the treatment of both produced waters.

关键词： Polycyclic aromatic hydrocarbons Indigenous community Wastewater treatment Functional gene

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Effectiveness and safety of subthreshold vibration over suprathreshold vibration in treatment of muscle fatigue in elderly people

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World Journal of Clinical Cases 2023年第15期11卷 3434-3443页

作者： Ayman A Mohamed Esra Khaled Asma hesham Ahmed Khalf Physical Therapy Nahda UniversityBeni Suef 23435Egypt Physical Therapy Beni-Suef UniversityBeni Suef 32456Egypt

Muscle fatigue is common in many populations,particularly *** increases the incidence of muscle fatigue and delays its *** is a huge debate about the current treatments for muscle fatigue,particularly in ***,it has been discovered that mechanoreceptors have an important role as a sensory system in sensing muscle fatigue which could enhance the body's response to muscle *** function of mechanoreceptors could be enhanced by applying either suprathreshold or subthreshold *** suprathreshold vibration improves muscle fatigue,it can cause desensitization of cutaneous receptors,discomfort,and paresthesia,which are barriers to clinical *** vibration has been approved as a safe and effective method of training for mechanoreceptors;however,its use and effectiveness in muscle fatigue have never been tested or *** physiological effects of subthreshold vibration in the treatment of muscle fatigue include:(1)Enhancing the function of mechanoreceptors themselves;(2)Increasing the firing rate and function of alpha motor neurons;(3)Increasing blood flow to fatigued muscles;(4)Decreasing the rate of muscle cell death in elderlies(sarcopenia);and(5)Driving motor commands and allow better performance of muscles to decrease fatigue *** conclusion,the use of subthreshold vibration could be a safe and effective treatment for muscle fatigue in *** could enhance recovery from muscle ***,subthreshold Vibration is safe and effective in treating muscle fatigue in comparison to suprathreshold vibration.

关键词： subthreshold Vibration Muscle Fatigue Elderly people

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Psychological impact of cancer scale:Turkish validity and reliability study

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World Journal of Psychiatry 2023年第6期13卷 351-360页

作者： Gülcan Bahçecioğlu Turan seda karaman Meyreme Aksoy Department of Nursing Faculty of Health SciencesFırat UniversityElazığ23100Turkey Faculty of Nursing Atatürk UniversityErzurum 25240Turkey Department of Nursing Faculty of Health SciencesSiirt UniversitySiirt 56500Turkey

BACKGROUND In the diagnosis and treatment of cancer,it is important to evaluate the components of psychological *** the key role of nurses in providing care to patients,it is important to evaluate patients,to determine highrisk patients and to use tools with acceptable validity and reliability to develop care *** To analyze the Turkish validity and reliability of The Psychological Impact of Cancer scale(PICs).METHODs This methodological study was conducted with 257 cancer patients admitted to the oncology-haematology clinic and outpatient clinic of a University Hospital between February and October *** the translation process of the scale,content and construct validity were *** factor analysis(EFA)and confirmatory factor analysis(CFA)was examined with construct validity,while item analyses and internal consistency analysis were conducted for *** Analyses and assessment results showed that the content validity index of the scale was *** the exploratory factor analysis of the Turkish adaptation study,total variance rate explained was found as 84.98%.Factor loads of all items were between 0.82 and *** was found that Cronbach Alpha values were between 0.860 and 0.930 and total scale Cronbach Alpha value was *** and CFA showed that Turkish form of 12-item and *** Psychological Impact of Cancer scale was confirmed with no changes to the original *** revealed good fit *** Turkish PICs is a valid and reliable measurement tool for the evaluation of individual’s psychological response to cancer diagnosis and treatment and for being used in clinical practice.

关键词： Cancer Patient Psychological impact Reliability Validity

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Can We Model Driver Perceptions?An In-situ Experiment in Real-World Conditions

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International Journal of Transportation science and Technology 2014年第2期3卷 149-165页

作者： Aly M.Tawfik hesham A.Rakha Department of Civil and Geomatics Engineering California State UniversityFresno2320 E.San Ramon Ave.Engineering East M/S 94FresnoCA 93740-8030 Charles E.Via Jr.Department of Civil and Environmental Engineering Virginia Tech Transportation Institute3500 Transportation Research PlazaBlacksburgVA 24061

It is clear that perceptions play a significant role in traveler ***,traveler perceptions are a corner stone in the feasibility of traveler information systems;for traveler information systems are only valuable if the drivers are incapable of accurately acquiring the provided information on their own,and if the provided information is relevant for the drivers’decision *** of traveler perceptions has been repeatedly researched in public transportation,and has been found to vary according to different ***,in spite of the clear significance of traveler perceptions,minimal effort has been put into modeling *** all travel behavior models are based on traveler experiences,which are assumed to reflect traveler perceptions via the addition of some random error *** works introduces an alternative approach:instead of adding an error component to represent driver perceptions,it proposes to model driver *** work is based on a real-world route choice experiment of a sample of 20 drivers who made more than 2,000 real-world route *** of the drivers’experiences,perceptions,and choices were recorded,analyzed and cross *** paper demonstrates that:i)driver experiences are different from driver perceptions,ii)driver perceptions explain driver choices better than driver experiences,iii)it is possible to model and predict driver perceptions of travel distance,time and speed.

关键词： travel Driver adding

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Optimized Tuned Deep Learning Model for Chronic Kidney Disease Classification

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Computers, Materials & Continua 2022年第2期70卷 2097-2111页

作者： R.H.Aswathy P.suresh Mohamed Yacin sikkandar s.Abdel-Khalek hesham Alhumyani Rashid A.saeed Romany F.Mansour Department of Computer science and Engineering KPR Institute of Engineering and TechnologyCoimbatore641407India Department of Medical Equipment Technology College of Applied Medical SciencesMajmaah UniversityAlMajmaah11952Saudi Arabia Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharga72511Egypt

In recent times,Internet of Things(IoT)and Cloud Computing(CC)paradigms are commonly employed in different healthcare *** gadgets generate huge volumes of patient data in healthcare domain,which can be examined on cloud over the available storage and computation resources in mobile *** Kidney Disease(CKD)is one of the deadliest diseases that has high mortality rate across the *** current research work presents a novel IoT and cloud-based CKD diagnosis model called Flower Pollination Algorithm(FPA)-based Deep Neural Network(DNN)model abbreviated as *** steps involved in the presented FPA-DNN model are data collection,preprocessing,Feature selection(Fs),and ***,the IoT gadgets are utilized in the collection of a patient’s health *** proposed FPA-DNN model deploys Oppositional Crow search(OCs)algorithm for Fs,which selects the optimal subset of features from the preprocessed *** application of FPA helps in tuning the DNN parameters for better classification *** simulation analysis of the proposed FPA-DNN model was performed against the benchmark CKD *** results were examined under different *** simulation outcomes established the superior performance of FPA-DNN technique by achieving the highest sensitivity of 98.80%,specificity of 98.66%,accuracy of 98.75%,F-score of 99%,and kappa of 97.33%.

关键词： Deep learning chronic kidney disease IoT cloud computing feature selection classification

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Improving electrical,optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites

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Journal of Rare Earths 2023年第12期41卷 2002-2009,I0007页

作者： shams A.M.Issa D.E.Abulyazied Albandari W.Alrowaily H.A.saudi E.s.Ali A.M.A.Henaish hesham M.H.Zakaly Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Faculty of science Al-Azhar UniversityAssiut BranchAssiut71524Egypt Polymer Lab Department of PetrochemicalEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Physics Department Faculty of ScienceTanta UniversityTanta31527Egypt Istinye University Faculty of Engineering and Natural SciencesComputer Engineering DepartmentIstanbul34396Turkey

This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding *** yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(sEM).The samples were investigated using absorption edge,transmittance spectra and dielectric *** transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te mperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the temperature *** correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)*** linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were *** to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.

关键词： Yttriumoxide/PVA Electrical properties Optical properties Gamma shielding Rare earths

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spatial distribution of air temperature and relative humidity in the greenhouse as affected by external shading in arid climates

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Journal of Integrative Agriculture 2019年第12期18卷 2869-2882页

作者： hesham AAhmed TONG Yu-xin YANG Qi-chang Abdulellah AAl-Faraj Ahmed MAbdel-Ghany Institute of Environment and sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory of Energy Conservation and Waste Management of Agricultural structures Beijing 100081P.R.China Department of Agricultural Engineering College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Agricultural Engineering Faculty of AgricultureSana'a UniversitySana'a 2124Yemen

The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, saudi Arabia. Two identical, evaporatively-cooled, single-span greenhouses were used in the experiment. One greenhouse was externally shaded(Gs) using a movable black plastic net(30% transmissivity), and the other greenhouse was kept without shading(Gc). strawberry plants were cultivated in both greenhouses. The results showed that the spatial distribution of the Tin and RHin was significantly affected by the outside solar radiation and evaporative cooling operation. The regression analysis showed that when the outside solar radiation intensity increased from 200 to 800 W m–2, the Tin increased by 4.5℃ in the Gc and 2℃in the Gs, while the RHin decreased by 15% in the Gc and 5% in the Gs, respectively. Compared with those in the Gc, more uniformity in the spatial distribution of the Tin and RHin was observed in the Gs. The difference between the maximum and minimum Tin of 6.4℃ and the RHin of 10% was lower in the Gs than those in the Gc during the early morning. Around 2℃ difference in the Tin was shown between the area closed to the exhausted fans and the area closed to the cooling pad with the external shading. In an evaporatively-cooled greenhouse in arid regions, the variation of the Tin and RHin in the vertical direction and along the sidewalls was much higher than that in the horizontal direction. The average variation of the Tin and RHin in the vertical direction was 5.2℃ and 10% in the Gc and 5.5℃ and 13% in the Gs, respectively. The external shading improved the spatial distribution of the Tin and RHin and improved the cooling efficiency of the evaporative cooling system by 12%, since the transmitted solar radiation and accumulated thermal energy in the greenhouse were significantly reduced.

关键词： greenhouse temperature humidity distribution uniformity evaporative cooling shading arid climate

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