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BIOCELL 2021年第5期45卷 1263-1271页

作者： MOHAMMAD EL-METWALLY MAMDOUH abdel-MOGIB MANAL ELFEDAWY GAAD SOHSAH AHMED REZK MAHMOUD moustafa MOHAMED SHAABAN Botany and Microbiology Department Faculty of ScienceDamanhour UniversityDamanhour22511Egypt Chemistry Department Faculty of ScienceMansoura UniversityEl-Mansoura35516Egypt Bioprocess Development Department Genetic Engineering and Biotechnology Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab CityAlexandria21934Egypt Biology Department College of ScienceKing Khalid UniversityAbha9004Saudi Arabia Chemistry of Natural Compounds Department Division of Pharmaceutical IndustriesNational Research CentreDokki-Cairo12622Egypt Organic and Bioorganic Chemistry Department of ChemistryBielefeld UniversityBielefeld33615Germany

Microorganisms are a huge mine of bioactive metabolites,and actinomycetes are one of the very active groups in this *** this article,we are concerned about the full taxonomical characterization of Streptomyces lividans AM,isolated from Egyptian *** isolate produced three new bioactive metabolites,namely:1-Nona-decanoyl,4-oleyl disuccinate(1),filoboletic acid;(9Z,11E)-8,13-dihydroxy octadeca-9,11-dienoic acid(2),and sitosteryl-3β-D-glucoside(3).Extensive 1D and 2D NMR and HR-mass spectrometry were used to elucidate the structures of the three ***,ten known compounds were also *** antimicrobial activity of the producing organism and newly reported compounds(1–3)was investigated against a selected group of pathogenic microorganisms.A full taxonomical characterization of the strain was described as well.

关键词： Bioactive metabolites Streptomyces sp. Taxonomy Biological activity

Wafer-level vapor cells filled with laser-actuated hermetic seals for integrated atomic devices

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Microsystems & Nanoengineering 2022年第6期8卷 225-235页

作者： Vincent Maurice Clément Carlé Shervin Keshavarzi Ravinder Chutani Samuel Queste Ludovic Gauthier-Manuel Jean-Marc Cote Rémy Vicarini moustafa abdel Hafiz Rodolphe Boudot Nicolas Passilly IEMN-Institut d’Electronique de Microélectronique et de Nanotechnologie UMR8520 CNRSUniversitéLilleCentrale LilleF-59000 LilleFrance FEMTO-ST Institute UMR6174 CNRSUniversitéBourgogne Franche-ComtéF-25030 BesançonFrance

Atomic devices such as atomic clocks and optically-pumped magnetometers rely on the interrogation of atoms contained in a cell whose inner content has to meet high standards of purity and ***-blowing techniques and craftsmanship have evolved over many decades to achieve such standards in macroscopic vapor *** the emergence of chip-scale atomic devices,the need for miniaturization and mass fabrication has led to the adoption of microfabrication techniques to make millimeter-scale vapor ***,many shortcomings remain and no process has been able to match the quality and versatility of glass-blown ***,we introduce a novel approach to structure,fill and seal microfabricated vapor cells inspired from the century-old approach of glass-blowing,through opening and closing single-use zero-leak microfabricated *** valves are actuated exclusively by laser,and operate in the same way as the“make-seals”and“break-seals”found in the filling apparatus of traditional *** structures are employed to fill cesium vapor cells at the *** make-seal structure consists of a glass membrane that can be locally heated and deflected to seal a *** break-seal is obtained by breaching a silicon wall between *** new approach allows adapting processes previously restricted to glass-blown *** can also be extended to vacuum microelectronics and vacuum-packaging of micro-electro-mechanical systems(MEMS)devices.

关键词： filled vacuum heated

Fabrication and Characterization of Tungsten Heavy Alloys Using Chemical Reduction and Mechanical Alloying Methods

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Open Journal of Applied Sciences 2013年第1期3卷 15-27页

作者： Zeinab abdel Hamid Sayed Farag moustafa Walid Mohamed Daoush Fatema abdel Mouez Mona Hassan Corrosion Control and Surface Protection Department Central Metallurgical R&D Institute Helwan Cairo Egypt Powder Technology Department Central Metallurgical R&D Institute Helwan Cairo Egypt

A novel reduction technique has been developed to synthesize nano-sized tungsten heavy alloys powders and compared with the same powders processed by mechanical alloying technique. In the first method, nano-sized tungsten heavy alloys powders have been obtained by reduction of precursors obtained by spray drying of several appropriate aqueous solutions, which were made from salts containing tungsten, cobalt, and nickel. By adjusting the stoichiometry of the component of the solutions, it is possible to obtain the desired chemical composition of the tungsten heavy alloys powders. In the second method, highly pure elemental powders of tungsten heavy alloys have been mechanically alloyed in a tumbler ball mill for different milling time. The investigated tungsten heavy alloy powders with the composition (95%W-3.5%Ni-1.5%Fe), (93%W-4.5%Ni-1.0%Fe-1.5%Co), and (90%W-6%Ni-4%Cu) have been prepared using both methods. The prepared powders have been compacted at 70 bar (200 MPa) and sintered in vacuum furnace at 1400℃. Vacuum sintering was carried out to achieve full densification of the produced tungsten heavy alloys. The investigated materials were going to be evaluated the physical and mechanical properties of the sintered parts such as density;electrical conductivity, hardness, and transverse rupture strength. The results reveal that, the grain size of alloys fabricated by chemical reduction technique (53.1 - 63.8 nm) is smaller than that fabricated by mechanical alloying technique (56.4 - 71.4 nm).

关键词： Tungsten Heavy Alloys Mechanical Alloying Chemical Reduction Powder Metallurgy Hardness Transverse Rupture Strength Conductivity

Impact of the aqueous extract of dandelion, probiotic and their synbiotic on male lamb’s testicular histopathology relative to semen characteristics

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Open Journal of Animal Sciences 2014年第1期4卷 23-30页

作者： moustafa Zeitoun Mohamed Farahna Khaled Al-Sobayil Ahmed abdel-Salam College of Applied Medical Sciences Qassim University Qassim KSA Department of Animal Production and Breeding Qassim University Buriedah KSA Department of Food Sciences and Human Nutrition College of Agriculture and Veterinary Medicine Qassim University Buriedah KSA

This study aimed at investigating effects of dandelion/probiotic on the testis histology and semen characteristics of male lambs. Twelve prepuberal Noemi male lambs (2 ± 0.4-month-old and 20 ± 3.5 kg B.W) were randomly allocated into four groups. Animals in group 1 were controlled, orally given normal saline as the same schedule of treated animals. In group 2 animals were given daily oral 50 ml of an aqueous extract of dandelion leaves. In group 3 animals were given a daily 50 ml of cow’s milk probiotics, and in group 4 animals were given 50 ml of a 1:1 mixture (dandelion extract: probiotic). Animals were treated for 8 consecutive weeks. At puberty, semen ejaculates were collected weekly for further 10 weeks. Thereafter, animals were sacrificed and testicles were obtained, weighed and a histopathological study was performed on the testis. Results revealed that oral administration of the dandelion aqueous extract to prepuberal lambs exhibited disturbances in the histological architecture of the testicular semeniferous tubules. Additionally, dandelion resulted in edematic interstitial tissues with evident vaculations. These deteriorations were reflected in less spermatogenesis (i.e. less sperm concentration and ejaculate volume by 10% and 20%, respectively than controlled group). Also, the percentage of sperm progressive motility was lower (P < 0.05) and dead sperm was higher (P < 0.05) in rams given dandelion than control. Administration of probiotic hasn’t revealed a change in the seminiferous tubules architecture, however, very little vaculation with rare edema was observed. Administration of the synbiotic mixture revealed intermediate histopathological appearances. The highest sperm concentration, testosterone concentration and advanced motility were obtained when probiotic was administered. In conclusion, although dandelion cures some hepatic malfunctions in human, caution must be taken into consideration of the frequent ingestion of dandelion for its harmful eff

关键词： Dandelion Histopathology Probiotic Ram Semen Testis

Fabrication and characterization copper/diamond composites for heat sink application using powder metallurgy

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Natural Science 2011年第11期3卷 936-947页

作者： Zeinab abdel Hamid Sayed F. moustafa Fatma A. Morsy Nevien abdel Atty khalifa Fatma abdel Mouez 不详

Copper composites reinforced with diamond particles were fabricated by the powder metallurgical technique. Copper matrix and diamond powders were mixed mechanically, cold com- pacted at 100 bar then sintered at 900?C. The prepared powders and sintered copper/diamond composites were investigated using X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray analysis (SEM/EDS). The effect of diamond contents in the Cu/diamond composite on the different properties of the composite was studied. On fracture surfaces of the Cu/uncoated diamond composites, it was found that there is a very weak bonding between diamonds and pure copper matrix. In order to improve the bonding strength between copper and the reinforcement, diamond particles were electroless coated with NiWB alloy. The results show that coated diamond particles distribute uniformly in copper composite and the interface between diamond particles and Cu matrix is clear and well bonded due to the formation of a thin layer from WB2, Ni3B, and BC2 between Cu and diamond interfaces. The properties of the composites materials using coated powder, such as hardness, transverse rupture strength, thermal conductivity, and coefficient of thermal expansion (CTE) were exhibit greater values than that of the composites using uncoated diamond powder. Additionally, the results reveals that the maximum diamond incorporation was attained at 20 Vf%. Actually, Cu/20 Vf% coated diamond com- posite yields a high thermal conductivity of 430 W/mK along with a low coefficient of thermal expansion (CTE) 6 × 10–6/K.

关键词： Powder Metallurgy Ceramic-Matrix Composites (CMCs) Ceramics Coating Electroless

A Standard Framework for Effective Progress Reports in the State of Kuwait

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American Journal of Operations Research 2018年第1期8卷 42-49页

作者： moustafa Kotb Mohamed Ibrahim abdel Razik Yousef S. Alolayan Structural Department Faculty of Engineering Al-Azhar University Cairo Egypt Reinforcement Concrete Department Al-Azhar University Cairo Egypt Faculty of Engineering Al-Azhar University Cairo Egypt

The construction industry in the State of Kuwait has recently witnessed a rapid growth as the volume of construction projects increased significantly over the past decade. Because of the progress and growth of the industry and the size of the projects, the volume of disputes between the parties to the various contracts has increased accordingly. As projects become larger and more complex, their management and control become more difficult, especially in the absence of effective standard systems to for managing project progress and determining the delay, if any. Even the simple issues, as well as the large ones, if neglected and unaddressed in a timely manner, can cause huge problems that concerns to all project parties. Irrespective of addressing and managing construction delays legally, the resulting legal disputes always have other negative effects on the contracting parties. If the parties to the contract have an insight that enables them to forecast and identify the issues that may cause a conflict before it occurs, that eliminates a myriad of problems before they occur, and greatly reduces the chances of further conflict between contracting parties. This paper presents a framework for a novel progress reporting system that can help minimize contract disputes in the state of Kuwait.

关键词： Construction Progress Reports Contract Disputes Contractor Selection Project Control

Fédération Internationale Des Ingénieurs Conseils (FIDIC) Variation Order Clause

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American Journal of Operations Research 2017年第6期7卷 372-375页

作者： moustafa Kotb Mohamed Ibrahim abdel Razik Reda Abbass Sabry Structural Department Faculty of Engineering Al-Azhar University Cairo Egypt Reinforcement Concrete Department Al-Azhar University Cairo Egypt M.Sc. DBA Al-Azhar University Cairo Egypt

To paraphrase the Greek philosopher Heraclitus, change is the only constant in construction projects. Changes in scope occur as projects progress from design through practical completion. FIDIC General Conditions Clause 13 [1] is one of the most important terms and implementing. It is also major factor for project success. Once all project parties understand and fairly use this clause, the impact will be minimising the expected disputes by 50% at least. Thus, this paper is considering illustrated variation order clause by flow chart technique to ensure that all the engineers are handling easily those subclasses.

关键词： Variation Order FIDIC VO Change Order Clause 13

Relationship between peripheral arterial disease, carotid intima-media thickness and C-reactive protein in elderly diabetic patients

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Advances in Aging Research 2013年第4期2卷 115-120页

作者： Moatassem Salah Amer Samia Ahmed Abdul-Rahman Wafaa Mostafa Abd-El Gawad Ibrahim Ahmad abdel Aal Ahmad abdel Khalek abdel Razek Mohamed Wessam El-Huseiny moustafa abdel Wahab Clinical Pathology Department Faculty of Medicine Mansoura University Mansoura Egypt Geriatrics and Gerontology Department Faculty of Medicine Ain Shams University Cairo Egypt Geriatrics and Gerontology Department Faculty of Medicine Mansoura University Mansoura Egypt Radiodiagnosis Department Faculty of Medicine Mansoura University Mansoura Egypt

Purpose: To study the association between carotid intima media thickness (CIMT) and high sensitivity CRP (hs-CRP) level as markers for PAD in elderly patients with DM. Subjects: A case-control study on 90 participants aged 60 years and older divided into 60 cases (30 patients with DM alone and 30 patients with DM and comorbidities) and 30 healthy controls. All were assessed by measuring CIMT, ankle brachial index (AB), and markers for cardiovascular disease such as high-sensitivity CRP (hs-CRP), total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), and low density lipoprotein (LDL). Results: hs-CRP levels showed statistically significant difference being highest among patients with DM and comorbidities and lowest among controls (P < 0.001). Also, symptoms of PAD were significantly higher among cases than controls. ABI was able to detect PAD in many asymptomatic patients. Color changes were present in only 43.30% (n = 26) of positive PAD cases while delayed wound healing, claudication pain, rest pain, cold extremities, and trophic changes were present in 23.30% (n = 14), 16.71% (n = 10), 16.71% (n = 10), 45.00% (n = 27), and 21.7% (n = 13). Using logistic regression analysis revealed that DM, CIMT, and hs-CRP were independent predictors for PAD (OR = 4.194, 7.236, 1.003;P value = 0.044, 0.25, 0.031) after adjustment of other coronary risk factors such as sex, smoking, hypertension, TC, and TG. Conclusion: Diabetic elderly have higher prevalence of asymptomatic PAD thannon-diabetics using solely ABI. DM, CIMT, and hs-CRP are independent predictors for the occurrence of PAD. Hs-CRP levels are highest among diabetics with comorbidities.

关键词： Peripheral Arterial Disease Carotid Intima-Media Thickness Ankle Brachial Index C-Reactive Protein Elderly

Numerical Investigation of the Geometric Phase and Entropy Squeezing for a Two-Level System in the Presence of Decoherence Terms

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Journal of Electromagnetic Analysis and Applications 2013年第9期5卷 359-365页

作者： moustafa M. Salama Ahmed O. Elnubi Sayed abdel-Khalek Mohamed A. El-Sayed 1Mathematics Department Faculty of Science Taif University Taif Saudi Araba 2Informatics Research Institute City of Scientific Research and Technology Applications Alexandria Egypt 1Mathematics Department Faculty of Science Taif University Taif Saudi Araba 2Facluty of Pure and Applied Science International University of Africa Khartoum Sudan. Mathematics Department Faculty of Science Taif University Taif Saudi Araba

In this paper, we have presented the numerical investigation of the geometric phase and field entropy squeezing for a two-level system interacting with coherent field under decoherence effect during the time evolution. The effects of the initial state setting and atomic dissipation damping parameter on the evolution of the geometric phase and entropy squeezing have been examined. We have reported some new results related to the periodicity and regularity of geometric phase and entropy squeezing.

关键词： Geometric Phase Field Entropy Squeezing Atomic Dissipation

Facile Preparation of Silver Halide Nanoparticles for Biological Application and Waste Water Treatment

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Advances in Nanoparticles 2023年第3期12卷 123-138页

作者： Islam M. I. moustafa Dina N. abdel Razek Zeinab A. Omran Naglaa M. Mohamed Chemistry Department Faculty of Science Benha University Benha Egypt

Highly efficient silver halide nanoparticles (AgX, X = Cl, Br NP’s) were successfully synthesized by facile and template-free direct-precipitation method using potassium chloride, potassium bromide and silver nitrate as reactive sources. The as-prepared AgX NP’s were characterized by FTIR, thermogravimetric analysis, XRD, EDX and HRTEM. The antimicrobial susceptibilities against two Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus) and four Gram-negative bacteria (Salmonella typhi, Escherichia coli, P. aeruginosa and Klebsiella pneumoniae) in addition to five fungi (Aspergillus flavus, A. carbonarus, Penicillium verrucosum, Fusarium verticelloides and A. niger) were tested by the disk diffusion technique. The antibacterial and antifungal results suggest that the prepared AgX NP’s show high activity against the tested organisms compared to tetracycline and Nystatin taken as standard drugs. As an application, the use of the prepared AgX NP’s as photo catalyst for the decontamination of malathion as VX chemical warfare agent (CWA) stimulant from water sample was extensively studied.

关键词： AgX Nanomaterials Antibacterial and Anti Fungal Activity Photo Catalytic Decontamination of Malathion