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Journal of Materials Science & Technology 2020年第22期54卷 146-152页

作者： Di Wang mahmoud ramadan Sith Kum seranee Suchada Punpruk Tingyue Gu Department of Chemical&Biomolecular Engineering Institute for Corrosion and Multiphase TechnologyOhio UniversityAthens 45701USA PTT Exploration and Production Bangkok 10900Thailand

In the oil and gas industry,microbiologically influenced corrosion(MIC) is a major threat to hydrotest,a procedure which is required to certify whether a pipeline can be *** is frequently used as a hydrotest *** this bio film prevention lab study,an oilfield biofilm consortium was grown in an enriched artificial seawater anaerobically at 37℃ for 60 *** combination of 100 ppm(w/w) 2,2-dibromo-3-nitrilopropionamide(DBNPA)+100 nM(180 ppb) Peptide A(a biofilm dispersal agent) led to extra SRB(sulfate reducing bacteria),APB(acid producing bacteria) and GHB(general heterotrophic bacteria) sessile cell count reductions of 0.9-log,0.8-log and 0.6-log,respectively,compared with the outcome obtained by using 100 ppm DBNPA *** Peptide Aenhancement also led to extra reductions of 44 % in weight loss,43 % in maximum pit depth,and 54 % in corrosion current density.

关键词： Hydrotest Microbiologically influenced corrosion Anti-biofilm peptide Biocide enhancer 2 2-dibromo-3-nitrilopropionamide(DBNPA)

Percutaneous Fixation as an Option for Traumatic Neurologically Intact Thoracolumbar Vertebral Fractures

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Open Journal of Modern Neurosurgery 2024年第4期14卷 246-255页

作者： Ahmed Hosameldin Ashraf Osman mahmoud Gomaa mahmoud ramadan Department of Neurosurgery Fayoum University Faiyum Egypt Department of Neurosurgery Beni-Suef University Beni Suef Egypt

Background: The most frequent spinal fracture is the thoracolumbar fracture. Minimally invasive percutaneous fixation of cases having thoracolumbar vertebral fractures without neurological impairments has remained controversial. The advantages of minimally invasive percutaneous fixation are decreasing muscle and soft tissue injury, decreasing blood loss and infection rate, in addition to shortening hospital stay and recovery times. In comparison to the open technique, percutaneous fixation is adequate for treating thoracolumbar (TL) fractures without causing neurological impairments & with satisfactory outcomes in terms of kyphosis decline. Elevated radiation exposure to the surgeon &the patient, lack of decompression and fusion via bone graft, & a steep learning curve are all disadvantages of percutaneous fixation of vertebral fractures. Methods: This study was retrospectively conducted on forty-eight patients, age ranging from 16 to 65 years old, with a thoracolumbar (TL) fracture without causing neurological impairments who were meeting the eligibility criteria for fixation in the period from July 2019 to January 2024. Results: We included the forty-eight patients who met the inclusion criteria (34 males and 14 females) their ages ranged from 16 to 65 years. The most common pathology was L1 fracture in 38 patients. No major complications were experienced, only wound infection in five patients which was treated efficiently with repeated dressings and broad-spectrum antibiotics. Four patients experienced misdirected screws, only in one patient the screw encroach into the spinal canal with no deficit experienced, while the other three showed minimally laterally deviated screws. Conclusion: The advantages of percutaneous pedicle screw fixation in thoracolumbar fractures through preservation of posterior musculature, are less blood loss, shorter operative time, lower infection risk, less post-operative pain, shorter rehabilitation time as well as a shorter hospital st

关键词： Thoracolumbar Fractures Fracture Stability Percutaneous Fixation

Boundary Layer Development on a Concave Surface： Flow Visualization and Hot Wire Velocity Measurements

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Journal of Energy and Power Engineering 2014年第7期8卷 1177-1182页

作者： Farouk Hachem mahmoud Khaled Mohamad ramadan Charbel Habchi ETF (Energy and Thermo-Fluids) Group School of Engineering L1U (Lebanese International University) Beirut 146404 Lebanon

Gortler vortices are key issues in the design of gas turbine blades. The present study deals with flow visualization over concave surface for gas turbine applications. The aim is to comprehend qualitatively the flow trends, particularly the Gortler vortices formation and development. Gortler vortices have the shape of mushroom-like vortices regularly spaced at 25 mm. These vortices grow and increase in strength more rapidly along the surface in the case of the same grid of turbulence applied to the measuring section. The curvature radius of the studied blade is 0.5 m and the stream turbulence intensity level is 2.6%. The velocity field is measured by hot wire anemometer in the streamwise direction. The velocity profile is found to be highly distorted by the momentum transfer associated with Gortler vortices. The results are compared to Blasius flow and to literature data for a blade with curvature radius equal to 2 m.

关键词： Gortler vortices concave surface flow visualization velocity profile gas turbine.

Prognostic and Clinicopathological Value of the Expression of FOXC2 &YKL-40 in Carcinoma of the Breast, an Immunohistochemical Study

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Advances in Breast Cancer Research 2018年第3期7卷 211-230页

作者： Enas M. Fouad Abla S. mahmoud Rham Z. Ahmed Basant Sh El Shafaay ramadan mahmoud Gamal Osman Mohamed Farouk Amin Loay M. Gertallah Manar A. Bessar Lecturer of Pathology Faculty of Medicine Zagazig University Zagazig Egypt Lecturer of Pathology Faculty of Medicine Beni-Suef University Cairo Egypt Lecturer of Medical Oncology Faculty of Medicine Zagazig University Zagazig Egypt Lecturer of Clinical Oncology & Nuclear Medicine Faculty of Medicine Zagazig Egypt Lecturer of General Surgery Faculty of Medicine Zagazig University Zagazig Egypt Lecturer of Radiology Faculty of Medicine Zagazig University Zagazig Egypt

Background: Breast cancer is considered the commonest and the most fatal female cancer worldwide. There is to an urgent need for discovering recent therapies to identify patient prognosis and improve treatment strategies. Fork-head Box C2 (FOXC2) is a transcription factor which is a key regulator of cancer stem cells (CSC) properties and epithelial mesenchymal transition (EMT) e.g. cancer initiation, metastatic capacity, and resistance to chemotherapy. FOXC2 roles in CSCs properties and EMT regulation in breast cancer needs detailed studies. YKL-40 is known as chitinase-3-like-1 belongs to a family of mammalian proteins that have an amino acid sequence which is similar to the 18-glycosyl hydrolase bacterial chitinases group. Recent studies have found aberrant YKL-40 elevated expression in cancer of various organs, so it may be used as a recent prognostic biomarker for patients with breast cancer. Former researchers have assessed the expression of FOXC2 & YKL-40 separately in cancer patients and relations to prognosis of patients;however, no studies assessed them together in breast cancer patients and the previous results were inconclusive. Accordingly, our study aimed at evaluation of immunohistochemical expressions of FOXC2 & YKL-40 in carcinoma of the breast in a trial to clarify the relation among their expressions, clinicopathological parameters and recurrence of the disease after successive therapy and patients’ prognosis. Methods: we have evaluated expressions of FOXC2 & YKL-40 in sections from 50 paraffin blocks of carcinoma of the breast using immunohistochemistry. We followed up our patients for 3 years for assessment of recurrence of the disease after successive therapy and survival rates. We analyzed the relationship between their combined expression clinicopathological and prognostic parameters. Results: high FOXC2 expression was associated with older age of the patient (p = 0.002), negative ER (p = 0.009), & PR (p = 0.008), positive HER2neu (p = 0.02),

关键词： Carcinoma of the Breast FOXC2 YKL-40 Prognosis Immunohistochemistry

Structural and Tectonic Evolution of El-Faiyum Depression,North Western Desert,Egypt Based on Analysis of Landsat ETM+,and SRTM Data

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Journal of Earth Science 2011年第1期22卷 75-100页

作者： Timothy M Kusky Talaat M ramadan mahmoud M Hassaan Safwat Gabr Three Gorges Research Center for Geo-hazard State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences The Geological Applications and Mineral Resources Division National Authority for Remote Sensing and Space Sciences (NARSS) Cairo Egypt

False color Landsat ETM＋（bands 7, 4, 2 in RGB） and SRTM images of the EI-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and N-S. Airborne magnetic data reveal some E-W subsurface faults which are not recognized on Landsat ETM＋ and SRTM images. Ratio images （5/7, 3/1, 4/3） and （5/7, 5/1, 4） were used for lithological discrimination of different rock types. The EI-Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of EI-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits （comprising fluviatile sediments and basalt sheets） and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1 ： 100 000 using Landsat ETM＋ and SRTM images coupled with extensive field work. The major structural trends are E-W, ENE, NS and NW--the same trends observed elsewhere in North Africa from NW Sudan to NE Egypt including north and central Sinai. EI-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, folds, push-up structures, and basins. Qarun Lake is located in the northern part of EI-Faiyum depression, at a right-step between two strands of the NE striking fault system. We have suggested elsewhere that EI-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The E-W structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of t

关键词： Egypt EI-Faiyum Syrian arc fold belt pull-apart basin Western Desert of Egypt.

A Novel Analytical Technique of the Fractional Bagley-Torvik Equations for Motion of a Rigid Plate in Newtonian Fluids

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 969-983页

作者： mahmoud H.Taha Mohamed A.ramadan Dumitru Baleanu Galal M.Moatimid Department of Mathematics Faculty of EducationAin Shams UniversityCairoEgypt Department of Mathematics&Computer Science Faculty of ScienceMenoufia UniversityShebin El-KomEgypt Department of Mathematics Cankaya UniversityAnkara06530Turkey Institute of Atomic Physics Magurele-Bucharest077125Romania Department of Medical Research China Medical University HospitalChina Medical UniversityTaichungTaiwan

The current paper is concerned with a modified Homotopy perturbation *** modification allows achieving an exact solution of an initial value problem of the fractional differential *** approach is powerful,effective,and promising in analyzing some classes of fractional differential equations for heat conduction problems and other dynamical *** crystallize the new approach,some illustrated examples are introduced.

关键词： Bagley-Torvik equation caputo sense Riemann-Liouville integral fractional differential equation

URBAN PLANNING:A TOOL FOR URBAN POVERTY ALLEVIATION IN SUDAN

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Chinese Geographical Science 2004年第2期14卷 110-116页

作者： Elnazir ramadan Department of Urban and Resources Sciences Nangjing University Nanjing 210093. P. R. China Department of Geography University of Juba 321/1 Khartoum Sudann the past few dacades urbanization and urban growth have been increasing rapidly in many of the developing countries. It is expected that over 50% of the world population will live in cities in 2005. The growing trend indicates that as many as one fifth of all households still remain with housing tenure problems which they try to solve through very expensive rentals insecurity socially and environmentally-hazardous squatting or unhealthy overcrowding sometimes ending up with none at all. And hence propcr planning is necessary in urban development policies to improve human settlement managements in a sustainable way. This article has tried to handle urban poverty in the Sudan to a reasonable level of detail. It dealt with selected areas with regard to promotion of sustainable human settlement. The study managed to identity some recent progress in Sudanese human settlements that is however still accompanied by numerous serious instances of decline in the urban environment especially that of the greater Khartoum. Such instances of environmental deterioration are profiled and analyzed by the study with respect to all human settlement aspects of management land-use infrastructure energy and transport. The paper's conclusion emphasized that improving all these aspects is of high priority.

In the past few dacades, urbanization and urban growth have been increasing rapidly in many of the developing countries. It is expected that over 50% of the world population will live in cities in 2005. The growing trend indicates that as many as one fifth of all households still remain with housing tenure problems, which they try to solve through very expensive rentals, insecurity, socially and environmentally-hazardous squatting or unhealthy overcrowding, sometimes ending up with none at all. And hence, proper planning is necessary in urban development policies to improve human settlement managements in a sustainable way. This article has tried to handle urban poverty in the Sudan to a reasonable level of detail. It dealt with selected areas with regard to promotion of sustainable human settlement. The study managed to identity some recent progress in Sudanese human settlements, that is, however, still accompanied by numerous serious instances of decline in the urban environment, especially that of the greater *** instances of environmental deterioration are profiled and analyzed by the study with respect to all human settlement aspects of management, land-use, infrastructure, energy and transport. The paper's conclusion emphasized that improving all these aspects is of high priority.

关键词：城市规划贫困经济发展苏丹

Inelastic displacement ratio of low-to mid-rise BRBFs designed under variable levels of seismicity

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 763-775页

作者： Hamdy Abou-Elfath Mostafa ramadan Faculty of Engineering Alexandria UniversityAlexandria 21544Egypt

Buckling-restrained braces(BRBs)have shown their capability to provide building structures with stiffness,strength,and *** the seismic drifts of buckling-restrained braced frames(BRBFs)is an important design step to control structural and non-structural *** current practice of seismic design,the estimation of seismic drifts of BRBFs is performed by using empirical calculations that are independent upon either the type of the structural system or the design level of *** these empirical calculations,the seismic drifts are estimated by amplifying the reduced elastic drifts obtained under design lateral loading with a displacement amplification factor(DAF).The value of DAF is considered equal to the product of the response modification factor R and the inelastic displacement ratioρ.The goal of the current research is to assess the value ofρfor low-to mid-rise BRBFs designed under low and high levels of *** goal has been achieved by conducting a series of elastic and inelastic time-history analyses pertaining to an ensemble of earthquake records on 3-,6-and 9-story *** results indicate that theρ-ratio increases with an increase in design seismic intensity and an increase in experienced *** range ofρfor low seismicity designs ranges from 0.63 to 0.9,while for high seismicity designs this range stretches from 0.83 to *** has been found that the consideration of a generalρ-ratio of 1.0 is a reasonable estimation for the design of the BRBFs considered in this study.

关键词： displacement amplification factor inelastic displacement ratio seismicity buckling-restrained brace seismic drift seismic design

Friction and wear of sand-contaminated lubricated sliding

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Friction 2018年第4期6卷 457-463页

作者： Mohamed Ahmed ramadan Faculty of Engineering at Helwan Helwan University

This paper reports a test investigation of friction and wear responses from sand contaminated lubricated sliding. The influence of sand contaminants on wear and friction is characterized. Analyses are completed utilizing segments of piston ring sliding against the cylinder liner. Paraffin oil, with and without sand contaminants, is utilized. The effects of the concentration and particle size of sand are examined. Based on the observations in the present work, we found that friction and wear increase with sand concentration in the lube. Solid proposals ought to be considered, in order to enlighten the general population on the importance of changing a car engine's oil filter regularly.

关键词： sand contamination lubrication oil abrasive wear lubricated sliding

Hyoscine N-butylbromide inhalation:they know,how about you?

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World Journal of Emergency Medicine 2023年第1期14卷 81-82页

作者： Hayri ramadan Department of Emergency Medicine Ankara Training and Research HospitalUniversity of Health SciencesAnkara 06230Turkey

Dear editor,Hyoscine N-butylbromide(HNB)is a quaternary ammonium compound with an anticholinergic effect and is commonly used as an antispasmodic drug.[1,2]HNB decreases motility in the gastrointestinal and genitourin... 详细信息

关键词： editor quaternary ammonium