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The Glenn Shunt Revisited, A Single Center Registry in ain shams university Cardiology Department

Congenital Heart Disease 2022年第1期17卷 71-85页

作者： Mina Tewfik Maiy El-Sayed Alaa Roushdy Soha Romeih Dina Ezzeldin Hebatalla Attia Cardiology Department Ain Shams UniversityCairoEgypt Prof.Magdy Yacoub Aswan Heart Centre AswanEgypt Cardiology Department Tanta UniversityTantaEgypt

Background:Bidirectional Glenn shunts have long been available as palliative procedures for patients with single ventricle physiology that is,patients unsuitable for biventricular *** our country they are performed at an older age than that recommended by the ***,we aim to assess post bidirectional Glenn shunt patients to detect the presence of any complications and to evaluate their functional ***:This was a descriptive study that included all patients who underwent a bidirectional Glenn shunt and were referred for follow up in ain shams university *** taking including NYHA class and physical activity,clinical examination,six-minutes-walk test,laboratory investigations,full echocardiographic assessment were done for all *** patients needed invasive cardiac ***:Our registry included 178 patients who underwent bidirectional Glenn procedure referred for follow up in ain shams university hospital from January 2019 till July *** mean age of the registry was 18.7±8.26 years(range between 5 and 37 years),85 males(48%)and 93 females(52%).Regarding the basic anatomy,double outlet right ventricle with hypoplastic left ventricle was the ***,our descriptive study confirmed many characteristic similarities between our patients and patients in developing *** patients underwent bidirectional Glenn shunt at a median age of 6 years which is considered a relatively old age but similar to other studies that have been made in developing countries like Pakistan,India and *** is a significant delay in the operation in Egyptian patients due to lack of patients’awareness,few numbers of primary health care facilities and high economic ***:Although the presence of slight systemic desaturation,our study demonstrated a satisfactory functional capacity among our patients;thus,bidirectional Glenn can be considered an acceptable definite univentricular repair in patients

关键词： Bidirectional Glenn shunt single ventricle univentricular repair

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Effect of Zn,Cu,Cr and Pb Chlorides on the Formation of Tricalcium Aluminate Trisulfate Hydrate

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Journal of Materials Science & Technology 2008年第6期24卷 867-872页

作者： Wafaa S.Hegazi Eisa E.Hekal Essam A.Kishar Maha R.Mohammed Faculty of Girls ain shams university CairoEgypt Faculty of Science ain shams university CairoEgypt

The effect of addition of Zn, Cu, Pb and Cr chlorides as admixtures on the hydration reaction of the system 3CaO·Al2O3-gypsum with molar ratio 1：3 was studied. Different ratios of each salt were used, namely 0.5%, 2% and 4% by weight of the solid mixture. Hydration reaction was carried out at 35℃ for various time intervals from 0.5 h to up to 7 d. Hydration rate of the system 3CaO·Al2O3-CaSO4·2H2O in absence and presence of different salts was studied via the determination of the combined water contents. X-ray diffraction analysis showed that the ettringite was the only hydration product formed in the different mixes. The hydration products were investigated by scanning electron microscopy （SEM） and thermal gravimetric analysis. The results indicated that the rate of formation of ettringite and its microstructure depend on the admixture and its dosage.

关键词： Tricalcium aluminate Hydration Ettringite formation Heavy metal

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Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： M.H.Abd-El Salam S.El-Gamal M.Mohsen D.M.Abd El-Maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDMS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDMS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDMS loaded with different contents of filler has been studied. Mullins ratio （RM） was found to be dependent on the filler type and content. It was found that, RM increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. Moreover, the hysteresis in PDMS-CB composites was more pronounced than in PDMS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDMS composites containing different fillers. A negative correlation was observed between Vf and RM.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

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Production of dimethylether(DME) as a clean fuel using sonochemically prepared CuO and /or ZnO- modified γ- alumina catalysts

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燃料化学学报 2014年第3期42卷 350-356页

作者： Sameh M.K.Aboul-Fotouh ain shams university Faculty of EducationChemistry Department

The catalytic conversion of methanol to dimethylether(DME)was studied over CuO/Al2O3,ZnO/Al2O3and ZnOCuO/Al2O3nanocatalysts prepared in presence or absence of ultrasonic *** catalysts were characterized by X-ray diffraction(XRD),surface characterization method(BET),scanning electron microscope(SEM),H2-temperature programmed reduction(H2-TPR)and temperature programmed desorption of ammonia(NH3-TPD).The experimental results show that during catalytic dehydration of methanol to dimethylether,the activities of the CuO/Al2O3,ZnO/Al2O3and ZnO-CuO/Al2O3catalysts prepared using ultrasonic treatment are much higher than those prepared in absence of *** shows that the use of ultrasonication results in much smaller *** and XRD show that the ultrasonication increases the surface area and pore volume of the catalysts.H2-TPR profiles indicated that reducibility of the sonicated nanocatalysts is carried out at lower ***3-TPD shows that ultrasound irradiation has enhanced the acidity of the nanocatalyst and hence enhanced catalytic performance for DME formation.

关键词： DME 燃料化学氧化铜氧化锌

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Energy and spatial momentum of charged rotating frames in tetrad gravity

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Chinese Physics B 2011年第11期20卷 90-101页

作者： Gamal G.L.Nashed Mathematics Department Faculty of ScienceAin Shams University

We compute the total energy and the spatial momentum of four charged rotating （Kerr-Newman） frames by using the gravitational energy-momentum 3-form within the framework of the tetrad formulation of the general relativity theory. We show how the effect of the inertial always makes the total energy divergent. We use a natural regularization method, which yields the physical value for the total energy of the system. We show how the regularization method works on a number of different rotating frames that are related to each other by the local Lorentz transformation. We also show that the inertial has no effect on the spatial momentum components.

关键词： teleparallel gravity energy-momentum Weitzenbock connection regularization teleparallelism

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Immobilization of Co(Ⅱ) Ions in Cement Pastes and Their Effects on the Hydration Characteristics

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Journal of Materials Science & Technology 2011年第1期27卷 74-80页

作者： Eisa Hekal Essam Kishar Wafaa Hegazi Maha Mohamed Chemistry Department Faculty of ScienceAin Shams University Chemistry Department Women s College for ArtsScience and EducationAin Shams University

The immobilization of Co（Ⅱ） in various cement matrices was investigated by using the solidification/stabilization（S/S） *** different cement pastes used in this study were ordinary Portland cement in absence and presence of water reducing-and water repelling-admixtures as well as blended cement with *** ratios of Co（Ⅱ） were used（0.5% and 1.0% by weight of the solid binder）.The hydration characteristics of the used cement pastes were tested via the determination of the combined water content,phase composition and compressive strength at different time intervals up to 180 *** degree of immobilization of the added heavy metal ions was evaluated by determining the leached ion concentration after time intervals extended up to 180 *** leachability experiments were carried out by using two modes：the static and the semi-dynamic leaching *** was noticed that the concentration of the leached Co2＋ ions in the static mode of leachability was lower than the solubility of its hydroxide in all the investigated cement pastes.

关键词： Hydration characteristic of cement Admixtures Immobilization Heavy metals

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Energy and momentum of rotating frames in tetrad gravity

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Chinese Physics B 2011年第10期20卷 101-111页

作者： Gamal G L Nashed Mathematics Department Faculty of Science Ain Shams University

Within the framework of the tetrad formulation of general relativity theory, we compute the total energy and momentum of four rotating frames using the gravitational energy-momentum 3-form. We show how the effect of inertia always makes the total energy divergent. We use a natural regularization method to obtain physical values for the total energy of the system and show how it works on a number of explicit examples. We also show by calculation that inertia has no effect on the momentum components.

关键词： teleparallel gravity, energy-momentum WeitzenbSck connection, regularization telepar-allelism

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Five-dimensional teleparallel theory equivalent to general relativity,the axially symmetric solution,energy and spatial momentum

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Chinese Physics B 2011年第11期20卷 102-109页

作者： Gamal G.L.Nashed Mathematics Department Faculty of ScienceAin Shams University

A theory of （4＋1）-dimensional gravity is developed on the basis of the teleparallel theory equivalent to general relativity. The fundamental gravitational field variables are the five-dimensional vector fields （pentad）, defined globally on a manifold M, and gravity is attributed to the torsion. The Lagrangian density is quadratic in the torsion tensor. We then give the exact five-dimensional solution. The solution is a generalization of the familiar Schwarzschild and Kerr solutions of the four-dimensional teleparallel equivalent of general relativity. We also use the definition of the gravitational energy to calculate the energy and the spatial momentum.

关键词： five-dimensional teleparallel equivalent of general relativity five-dimensional solution energy and spatial momentum

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Lymphocytic colitis: A clue to bacterial etiology

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World Journal of Gastroenterology 2005年第46期11卷 7266-7271页

作者： Thanaa EA Helal Naglaa S Ahmed Osama Abo El Fotoh Department of PathologyFaculty of Medicine Ain Shams UniversityEgypt Department of Internal MedicineFaculty of Medicine Ain Shams UniversityEgypt

AIM： To find out the role of bacteria as a possible etiological factor in lymphocytic colitis. METHODS： Twenty patients with histopathological diagnosis of lymphocytic colitis and 10 normal controls were included in this study. Colonoscopic biopsies were obtained from three sites （hepatic and splenic flexures and rectosigmoid region）. Each biopsy was divided into two parts. A fresh part was incubated on special cultures for bacterial growth. The other part was used for the preparation of histologic tissue sections that were examined for the presence of bacteria with the help of Giemsa stain. RESULTS： Culture of tissue biopsies revealed bacterial growth in 18 out of 20 patients with lymphocytic colitis mostly Escherichia coil （14/18）, which was found in all rectosigmoid specimens （14/14）, but only in 8/14 and 6/14 of splenic and hepatic flexure specimens respectively. In two of these cases, E coli was associated with proteus. Proteus was found only in one case, Klebsiella in two cases, and Staphylococcus aureus in one case. In the control group, only 2 out of 10 controls showed the growth of E coli in their biopsy cultures. Histopathology showed rod-shaped bacilli in the tissue sections of 12 out of 14 cases with positive E coli in their specimen＇s culture. None of the controls showed these bacteria in histopathological sections. CONCLUSION： This preliminary study reports an association between E coli and lymphocytic colitis, based on histological and culture observations. Serotyping and molecular studies are in process to assess the role of E coli in the pathogenesis of lymphocytic colitis.

关键词： Lymphocytic colitis E coli Histopathology Culture

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Assessment of clay stiffness and strength parameters using index properties

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 579-593页

作者： Sayed M.Ahmed Structural Engineering Department Ain Shams University

A new approach is developed to determine the shear wave velocity in saturated soft to firm clays using measurements of the liquid limit, plastic limit, and natural water content with depth. The shear wave velocity is assessed using the site-specific variation of the natural water content with the effective mean stress. Subsequently, an iterative process is envisaged to obtain the clay stiffness and strength *** at-rest earth pressure coefficient, as well as bearing capacity factor and rigidity index related to the cone penetration test, is also acquired from the analyses. Comparisons are presented between the measured clay parameters and the results of corresponding analyses in five different case studies. It is demonstrated that the presented approach can provide acceptable estimates of saturated clay stiffness and strength parameters. One of the main privileges of the presented methodology is the site-specific procedure developed based on the relationships between clay strength and stiffness parameters, rather than adopting direct correlations. Despite of the utilized iterative processes, the presented approach can be easily implemented using a simple spreadsheet, benefiting both geotechnical researchers and practitioners.

关键词： Soft to firm clays Atterberg limits Shear wave velocity Small-strain shear modulus Constrained modulus Undrained shear strength Effective friction angle Cone penetration test

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