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Ore Controls and Metallogenesis of Au-Ag Deposits at Atalla Mine,Central Eastern Desert of Egypt

Acta Geologica Sinica(English Edition) 2020年第5期94卷 1451-1470页

作者： Mohamed abd el MONSEF Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geological Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the Atalla area occur as hydrothermal quartz veins in NE–SW pre-existing fractures within the Atalla granitic *** orientation of such quartz veins has been attributed to extensional behavior related to the Atalla Shear Zone(ASZ).The Atalla area is covered by a variety of lithologies that are(from oldest to youngest):metasedimentary rocks,metavolcanic rocks,ophiolite assemblage(serpentinites/talc-carbonates),Atalla granite and Dokhan volcanic ***,Atalla granite ranges in composition from granodiorite to *** geochemistry constrains the calc-alkaine affinity of the Atalla granite that was intruded within an orogenic(syncollision)tectonic *** ore minerals are represented by gold/silver(electrum),pyrite(Py1&Py2),arsenopyrite,pyrrhotite,sphalerite,chalcopyrite,galena,covellite and *** temperature of ore formation ranges from 240 to 285℃and the estimated fluid pressure is in the range of 20–100 *** on the geological setting,ore textures and fluid characteristics;the Atalla Au-Ag deposits are considered to be orogenic in nature,formed from a continental collision(~653-590 Ma),synchronous with the emplacement of calc-alkaline magmatism during the evolutionary history of the Arabian Nubian Shield(ANS).The initial ore-forming fluid was primarily derived from a metamorphic source related to ophiolitic-serpentinite rocks under deep regional conditions of greenschist-amphibolite facies,where the Atalla granitic eruption provided the required temperature conditions for the metamorphic process to take *** such conditions,the transportation of ore metals as bisulfide complexes is *** deposition of ore minerals was triggered by fluidwallrock interaction through fracture pathways in conjunction with a temperature-pressure drop that is likely to have been related to uplift into the crustal levels.

关键词： Gold-silver arsenopyrite geothermometry fluid inclusions orogenic deposits Atalla Shear Zone(ASZ)

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Effect of Cyclic Stress Reduction on the Creep Characteristics of AZ91 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1065-1073页

作者： Alaa Farag abd el-Rehim Physics Department Faculty of Science King Khalid University Physics Department Faculty of Education Ain Shams University

The creep deformation behavior of aged AZ91 magnesium alloy under the cyclic stress reduction has been investigated in the temperature range 353–383 K. The microstructural evolution of the AZ91 magnesium alloy at different heat treatment conditions has been studied using optical microscopy and scanning electron microscopy. The minimum strain rate, e_min, was found to be higher under cyclic stress reduction condition than that under static creep condition for the same maximum stress. Cyclic creep acceleration is interpreted using the interaction of moving dislocations with the existing b-phase（Mg17Al12） precipitates. The mean value of the activation energy of secondary creep stage was found to be equal to that quoted for lattice self-diffusion of magnesium mechanism.

关键词： Magnesium alloys Microstructure Cyclic stress Dislocations

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Physical Studies of Some Hydrazinobenzoic Acid Complexes

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Journal of Materials Science & Technology 2005年第1期21卷 140-144页

作者： M.G.abd el Wahed S.abd el Wanees M.el Gamel S.abd el Haleem Faculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig EgyptFaculty of Science Zagazig University Zagazig Egypt

The stability constants of complexes of 2-hydrazinobenzoic acid and 4-hydrazinobenzoic acid with Ni (Ⅱ), Cu (Ⅱ), Zn (Ⅱ), Cd (Ⅱ), and Hg (Ⅱ) were determined potentiometricaIly at different temperatures. The thermodynamic parameters, △G0, △H0, and △S0 were calculated and proved that the complexation process is spontaneous and endothermic. The thermodynamic functions were analyzed in terms of electrostatic and non-electrostatic components and the results reveal that ionic bonds are formed between the studied ligands and metal ions. Conductometric titration was shown that the stoichiometry of the formed complexes are M:L and M:2L. The structure of the prepared solid complexes was characterized using IR, 1H NMR, 13C NMR spectroscopies as well as X-ray diffraction technique. Finally electrical conductivity of the ligands and their copper complexes was measured and shown that the ligands have a semiconductor behaviour.

关键词： Potentiometric titration Stability constants Thermodynamic parameters Structure of metal complexes

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Serologic, endoscopic and pathologic findings in pediatric celiac disease: A single center experience in a low/middle income country

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World Journal of Clinical Pediatrics 2022年第3期11卷 295-306页

作者： Hala H Mansour Nabil A Mohsen Mortada HF el-Shabrawi Somia M Awad Dalia abd el-Kareem Department of Pediatrics Faculty of Medicine Kasr Al AinyCairo UniversityCairo 12411Egypt Department of Pathology Cairo UniversityCairo 11562Egypt

BACKGROUND Studies in Africa,Asia,and Latin America are needed to provide a comprehensive picture of the global incidence of celiac disease(CD).AIM To describe the serology,endoscopic and histological findings in typical and atypical presentations of pediatric CD at a tertiary referral hospital in an African low/middle income country(LMIC).METHODS This observational study was conducted on 199 patients with CD from 2010 to *** patients were divided into typical and atypical groups according to the presenting symptoms including 120 and 79 patients ***,upper gastrointestinal endoscopy with duodenal biopsy were performed for patients who had symptoms suggestive of *** severity of the intestinal damage was graded according to the histo-pathologic Marsh-Oberhuber *** Chronic diarrhea was the main intestinal presentation in the typical *** was the most common extraintestinal symptom in both the typical and atypical ***-Oberhuber type 3b and 3c was significantly higher in the seropositive patients with a P value of 0.007.A significant correlation was observed between the histological grade of the biopsied duodenal mucosa and the clinical presentation(P<0.001).Age was significantly higher in the atypical group(P value<0.001).CONCLUSION Although typical CD was observed in 120 patients in this study,the clinical variability of the condition was frequently *** only was a significant predictor for the appearance of atypical ***,CD presentations in LMIC are not different from industrialized countries.

关键词： Typical Atypical celiac disease Celiac serology Marsh-Oberhuber histopathology

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Deep CNN Model for Multimodal Medical Image Denoising

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Computers, Materials & Continua 2022年第11期73卷 3795-3814页

作者： Walid el-Shafai Amira A.Mahmoud Anas M.Ali el-Sayed M.el-Rabaie Taha E.Taha Osama F.Zahran Adel S.el-Fishawy Naglaa F.Soliman Amel A.Alhussan Fathi E.abd el-Samie Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia Alexandria Higher Institute of Engineering&Technology(AIET) AlexandriaEgypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia

In the literature,numerous techniques have been employed to decrease noise in medical image modalities,including X-Ray(XR),Ultrasonic(Us),Computed Tomography(CT),Magnetic Resonance Imaging(MRI),and Positron Emission Tomography(PET).These techniques are organized into two main classes:the Multiple Image(MI)and the Single Image(SI)*** the MI techniques,images usually obtained for the same area scanned from different points of view are used.A single image is used in the entire procedure in the SI *** denoising techniques can be carried out both in a transform or spatial *** paper is concerned with single-image noise reduction techniques because we deal with single medical *** most well-known spatial domain noise reduction techniques,including Gaussian filter,Kuan filter,Frost filter,Lee filter,Gabor filter,Median filter,Homomorphic filter,Speckle reducing anisotropic diffusion(SRAD),Nonlocal-Means(NL-Means),and Total Variation(TV),are ***,the transform domain noise reduction techniques,including wavelet-based and Curvelet-based techniques,and some hybridization techniques are ***,a deep(Convolutional Neural Network)CNN-based denoising model is proposed to eliminate Gaussian and Speckle noises in different medical image *** model utilizes the Batch Normalization(BN)and the RelU as a basic *** a result,it attained a considerable improvement over the traditional *** previously mentioned techniques are evaluated and compared by calculating qualitative visual inspection and quantitative parameters like Peak Signal-to-Noise Ratio(PSNR),Correlation Coefficient(Cr),and system complexity to determine the optimum denoising algorithm to be applied *** on the quality metrics,it is demonstrated that the proposed deep CNN-based denoising model is efficient and has superior denoising performance over the traditionaldenoising techniques.

关键词： Image enhancement medical imaging speckle noise Gaussian noise denoising filters CNN denoising

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Gauss Gradient and SURF Features for Landmine Detection from GPR Images

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Computers, Materials & Continua 2022年第6期71卷 4457-4486页

作者： Fatma M.el-Ghamry Walid el-Shafai Mahmouad I.abdalla Ghada M.el-Banby Abeer D.Algarni Moawad I.Dessouky Adel S.elfishawy Fathi E.abd el-Samie Naglaa F.Soliman Department of electronics and Communications Engineering Faculty of EngineeringZagazig UniversityZagazigSharqia44519Egypt Department of electronics and electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenoufia32952Egypt Department of Industrial electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Recently,ground-penetrating radar(GPR)has been extended as a well-known area to investigate the subsurface ***,its output has a low resolution,and it needs more processing for more *** paper presents two algorithms for landmine detection from GPR *** first algorithm depends on a multi-scale technique.A Gaussian kernel with a particular scale is convolved with the image,and after that,two gradients are estimated;horizontal and vertical ***,histogram and cumulative histogram are estimated for the overall gradient *** bin values on the cumulative histogram are used for discrimination between images with and without ***,a neural classifier is used to classify images with cumulative histograms as feature *** second algorithm is based on scale-space analysis with the number of speeded-up robust feature(SURF)points as the key parameter for *** addition,this paper presents a framework for size reduction of GPR images based on decimation for efficient *** further classification steps can be performed on images after *** sensitivity of classification accuracy to the interpolation process is studied in detail.

关键词： GPR images cumulative histogram gradient image neural classifier SURF

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Congruence Pairs of Decomposable MS-Algebras

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Chinese Annals of Mathematics,Series B 2021年第4期42卷 561-574页

作者： Sanaa el-ASSAR abd el-Mohsen BADAWY Department of Mathematics Faculty of ScienceTanta UniversityTantaEgypt

In this paper,the authors first introduce the concept of congruence pairs on the class of decomposable MS-algebras generalizing that for principal MS-algebras(see[13]).They show that every congruence relationθon a decomposable MS-algebra L can be uniquely determined by a congruence pair(θ_(1),θ_(2)),whereθ_(1)is a congruence on the de Morgan subalgebra L^(∞)of L andθ_(2)is a lattice congruence on the sublattice D(L)of *** obtain certain congruence pairs of a decomposable MS-algebra L via central elements of ***,they characterize the permutability of congruences and the strong extensions of decomposable MS-algebras in terms of congruence pairs.

关键词： MS-Algebras Decomposable MS-algebras Congruence pairs Strong extension Permutability Congruence lattices

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Genetic Analysis of Familial Mediterranean Fever among Egyptian Patients

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Open Journal of Immunology 2022年第4期12卷 137-147页

作者： Marwa A. Besar Adel abd el Salam asmaa F. Enein Samar Tharwat Radwan Fatma Hamdy Fouad Abeer Saad Ali el Zekred Nehed abdallah Hassan Internal Medicine (Rheumatology & Immunology) Mansoura School of Medicine Mansoura University Al Mansoura Egypt Department of Biochemistry Specialized Medical Hospital Specialised Medical Hospital Mansoura Egypt Specialised Medical Hospital Mansoura Egypt

Background: Familial Mediterranean fever (FMF) is an autoinflammatory genetic disorder that associated with different genetic mutations. Frequency of clinical manifestation differs according to age group, geographic region and ethnic population. Objectives: To study the clinical manifestation of FMF in relation to genotype (M680I, M694V, M694I and V726A). Result: The main presentation of studied group was abdominal pain 65.9% (203), followed by fever 60.4% (186) patients. (Mutation M694V) was the commonest 47.6% (297), followed by (Mutation V726A) in 32.8% (169%), then (Mutation M6802) in 23.4% (121) lastly (Mutation M6941) was in 22.1% (114) patients. Fever was highly associated with mutation (V729A) and it was statistically significant (*p value 0.047). Conclusion: abdominal pain and fever were the most common manifestation of FMF patients. (Mutation M694V), (Mutation V726A) were the most detected mutation. Third age group;fever was associated with genetic mutation (V726A), abdominal pain with (M6941).

关键词： Familial Mediterranean Fever (FMF) MEFV Gene Mutation (M680I M694V M694I and V726A) Fever abdominal Pain Autoinflammatory

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COVID-19 and hepatic injury: cellular and molecular mechanisms in diverse liver cells

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World Journal of Gastroenterology 2023年第3期29卷 425-449页

作者： Fares E M Ali Mostafa K abd el-Aziz Mahmoud M Ali Osama M Ghogar Adel G Bakr Department of Pharmacology and Toxicology Faculty of PharmacyAl-Azhar UniversityAssiut 71524Egypt Department of Pharmacology Al-Azhar UniversityAssiut 71524Egypt Department of Biochemistry Faculty of Pharmacy Badr University in AssiutEgypt

The coronavirus disease 2019(COVID-19)represents a global health and economic *** injuries have been approved to be associated with severe acute respiratory syndrome coronavirus(SARS-CoV-2)*** viral tropism pattern of SARS-CoV-2 can induce hepatic injuries either by itself or by worsening the conditions of patients with hepatic ***,other factors have been reported to play a crucial role in the pathological forms of hepatic injuries induced by SARS-CoV-2,including cytokine storm,hypoxia,endothelial cells,and even some treatments for *** the other hand,several groups of people could be at risk of hepatic COVID-19 complications,such as pregnant women and *** present review outlines and discusses the interplay between SARS-CoV-2 infection and hepatic injury,hepatic illness comorbidity,and risk ***,it is focused on the vaccination process and the role of developed vac-cines in preventing hepatic injuries due to SARS-CoV-2 infection.

关键词： COVID-19 Hepatic injury Viral tropism COVID-19 comorbidity Vaccination

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Coronavirus Infection during Pregnancy: A 1-Year Experience among Pregnant Egyptian Women

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Open Journal of Obstetrics and Gynecology 2022年第5期12卷 361-374页

作者： Eman Aly abd el Fattah Faculty of Medicine Alexandria University Alexandria Egypt Department of Obstetrics and Gynecology Shatby Maternity Hospital Alexandria Egypt

Objectives: This study aimed to investigate the effect of COVID-19 on fetal well-being and perinatal outcomes. Methods: Pregnant women with documented COVID-19 infection who visited the antenatal care clinic of el Shatby Maternity Hospital, Alexandria, Egypt, from May 2020 to May 2021 were selected and classified into three groups according to the illness severity: mild, moderate, and severe. Fetal well-being was examined using the umbilical and cerebral Doppler and nonstress test (NST). The estimated fetal weight and amniotic fluid volume were also evaluated. After delivery, the neonates were evaluated through Apgar scoring at 1 and 5 min, cord blood samples, and neonatal nasopharyngeal swabs. Results: Abnormal umbilical and cerebral Doppler findings, abnormal NST results, higher incidence of cesarean section (CS) and emergency CS, and poor perinatal outcomes were observed in severe cases. Moderate and mild maternal infections had neither an adverse perinatal outcome nor an effect on the mode of delivery. Conclusion: Severe COVID-19 infection can affect the perinatal outcome.

关键词： Pregnancy COVID-19 Fetus Neonatal Infection

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