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A Wearable Dual-Band Dielectric Patch Antenna for LTE and WLAN

Journal of Electromagnetic Analysis and Applications 2012年第7期4卷 305-309页

作者： mohamed Ali Soliman Taha ElsayedTaha wael Elsayed Swelam Ali mohamedGomaa Faculty of Electronic Engineering Menoufia University Menouf Egypt National Telecom Regulatory Authority Cairo Egypt RF/Microwave and Photonics Group Dep. of ECE University of WaterlooWaterloo Ontario Canada Shobraa Faculty of Engineering Benha University Cairo Egypt

In this paper, a dual-band microstrip patch array antenna for both the Multiple Input Multiple Output (MIMO) 4G Long-Term Evolution (LTE) and the Wireless Local Area Network (WLAN) systems is developed. Design simulation and optimization processes are carried out with the aid of the Advanced Design System (ADS) electromagnetic simula-tor that uses the full–wave Method of Moment (MoM) numerical technique [1]. Rectangular microstrip patch antenna constructed from Multi-Walled Carbon Nanotubes (MWCNT) ink with electrical conductivity of 2.2 × 104 S/m and relative permittivity of 5-j1 is used as the conductor patch [2]. The patch is deposited on Rogers substrate RT-Durid 5880 single substrate with (εr = 2.2) and thickness of 62 mil. U-shape slot is used to provide the dual-band. The pro-posed antenna operates at 3.5 GHz for LTE and 5 GHz for WLAN. The proposed antenna parameters are compared with published result of copper patch [3,4] for the same application. Great enhancement in antenna size, matching, and frequency band width are achieved for the proposed antenna at the expense of gain and antenna efficiency compared with copper one. The proposed MWCNT dielectric antenna size is 18.4 mm × 27 mm compared with size of 27 mm × 37 mm for copper one respectively. The gain is better than 7dBi with antenna efficiency of 87.29% at 3.5GHz for cop-per patch antenna and is better than 1.692 dBi with antenna efficiency of 27.05% at 3.5GHz for MWCNT respectively.

关键词： U-Slotted Patch Antenna MWCNT Dielectric Antenna and ADS

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Recurrence of Cortical Venous Haemangioma in the Tibia: Interest of Sclerotherapy

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International Journal of Clinical Medicine 2015年第9期6卷 661-666页

作者： mohamed Bouabdellah Madiha Mahfoudhi Imen Gorsane Hatem Rajhi wael Chabbi Ramzi Bouzidi Orthopedy Department Charles Nicolle Hospital Tunis Tunisia Internal Medicine A Department Charles Nicolle Hospital Tunis Tunisia Radiology Department Charles Nicolle Hospital Tunis Tunisia

We report on a rare case of an intra-osseous haemangioma involving the medial portion of tibia in a 29-year-old man. The aim is to emphasize on diagnosis difficulties, possible recurrence and interest of sclerotherapy. In radiographs, the lesion was a well-defined osteolytic lesion having 3 mm of diameter with perimeter’s sclerosis. The computed tomography images demonstrated an intra-medullar gap’s image of the tibia with cortical participation. An osteoid osteoma was evocated but eliminated by the histhological examination. The osseous scintigraphy didn’t find any anomaly. The outcome was marked by the recurrence of pain. T1-weighted Magnetic resonance imaging showed a hypointense lesion, while T2-weighted images revealed hyperintense areas, with internal, hypointense septa. Gadolinium-enhanced T1-weighted images showed lattice-like enhancement of the lesion. These images signed a recurrence of the intra-osseous venous haemangioma. The sclerotherapy improved the pain in three days and prevented another recurrence.

关键词： Intra-Osseous Haemangioma Computed Tomography Magnetic Resonance Imaging Tibia Sclerotherapy

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Recovery of oil and free fatty acids from spent bleaching earth using sub-critical water technology supported with kinetic and thermodynamic study

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Advances in Bioscience and Biotechnology 2014年第3期5卷 261-272页

作者： Rehab Abdel Fattah N. A. Mostafa mohamed S. Mahmoud wael Abdelmoez Chemical Engineering Ddepartment Minia University Minia Egypt Faculty of Aapplied Mmedical Sscience Taif Uni-versity Taif KSA

This work represents the extraction of oil with high free fatty acid content from spent bleaching earth using sub-critical water technology as a greener production pathway. The extraction efficiencies under different conditions were investigated. The studied parameters include temperatures in the range of 180 to 270°C, the feed to solventfeed-to-solvent (in this case water) ratio (1:1, 1:2, 1:3, 1:4 and 1:5) and extraction times in the range of 5-60 minutes. The results showed that the optimum temperature, feed to solventfeed-to-solvent ratio, and extraction time were 270°C, 1:3, and 20 minutes, respectively. In another experiment, the extracted free fatty acids were converted into mono-, di-, and triglycerides through esterification with glycerol to increase the value added of the extracted products. The kinetics of the extraction process was found to be corresponding to an irreversible consecutive unimolecular-type first order reaction, consisting of the extraction step followed by the decomposition reaction step. Both reaction rates of extraction and decomposition were estimated using the reaction rate equations utilizing the nonlinear regression method. The apparent activation energy was calculated to be 46.1 kJ·mol-1. This result indicates a diffusion controlled reaction. For more exploration and deep understanding of the extraction mechanism, other thermodynamic parameters were also calculated and analyzed including,ΔH#, ΔS#, and ΔG# of the extraction step.

关键词： Spent Bleaching Earth Sub-Critical Water Technology Kinetics of Extraction Thermodynamic Parameters

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Endometrial Scratch-Suction and Implantation Failure

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Open Journal of Obstetrics and Gynecology 2014年第5期4卷 217-227页

作者： wael S. Nossair Manal M. El Behery mohamed Al S. Farag Department of Obsteterics and Gynaecology Faculty of Medicine Zagazig University Zagazig Egypt

Objective: The aim of this trial was to determine whether endometrial scratch-suction caused by insertion tube of (IUCD) with suction improved the probability of pregnancy in the subsequent IVF cycle in patients who had previous failed IVF outcome by removing small polyps and any hazardous materials. Design: Observational prospective cohort experimental study. Setting: Zagazig University Hospital, Obstetrics and Gynecology department. From period between September 2011 till September 2012. Population: 30 patients with previous failed IVF despite transfer of goodquality embryos were allocated to endometrial scratch-suction in the same the cycle of embryo transfer. Methods: From day 5 to day 7 of same ICSI cycle, the patients in study underwent endometrial scratch-suction technique. After preparation of insertion tube of (IUCD) and infant feeding tube 8 F, moving the insertion tube of IUCD from below upwards with scratching anterior uterine wall, then posterior, then left lateral uterine wall, then right lateral uterine wall, then fundus, all these steps are associated with suction by attaching proximal end of infant feeding tube 8 F to suction apparatus. Main Outcome Measures: Implantation and clinical pregnancy rates. Results: The implantation occurred in 24/30 (80%). The clinical pregnancy occurred in 20/30 patients (66.66%). 12/30 patients (40%) during scratch-suction technique had small fleshy masses obstructing suction tube which were small endometrial polyps. Conclusions: Endometrial scratch-suction improves clinical pregnancy and implantation rates in the same IVF-ET cycle in patients with previous unsuccessful IVF cycles.

关键词： Endometrial Scratch-Suction IVF/ICSI Endometrial Polyps Chemical Pregnancy Clinical Pregnancy

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Free-space optical channel characterization in a coastal environment

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Journal of Communications and Information Networks 2017年第4期2卷 100-106页

作者： wael G.Alheadary Ki-Hong Park Boon S.Ooi mohamed-Slim Alouini Computer Electricaland Mathematical Sciences and Engineering(CEMSE)DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal23955-6900Saudi Arabia

Recently,FSO(Free-Space Optical Communication)has received a lot of attention thanks to its high data-rate transmission via unbounded unlicensed ***,some weather conditions lead to significant degradation of the FSO link *** on this context and in order to have a better understanding of the capabilities of FSO communication in a coastal environment,the effects of temperature and humidity on an FSO system are investigated in this *** experiment is conducted using an open source FSO system that achieves a transmission rate of 1 Gbit/s at a distance of 70 *** new mathematical models are proposed to represent the effects of temperature and humidity on our developed FSO system operating at a wavelength of 1550 *** first model links the FSO attenuation coefficient to the air temperature in coastal regions,while the second model links the FSO attenuation coefficient to the humidity and the dew-point *** key finding of this study is that FSO links can achieve maximum availability in a coastal city with normal variations in temperature and humidity.

关键词： FSO optical systems relative humidity temperature channel characterization attenuation coefficient

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Anterolateral Approach for Unstable Lumbar Burst Fracture with Anterior Compression

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Open Journal of Modern Neurosurgery 2018年第2期8卷 201-214页

作者： wael A. Hammad mohamed A. Barania Islam M. Alaghory Ahmed M. El Sherif Department of Neurosurgery Al-Azhar University Hospitals Cairo Egypt

Background: Lumbar burst fractures are common spinal injuries that cause severe instability with kyphotic deformities and neurological complications requiring surgical decompression and reconstruction with spinal instrumentation for unstable burst fracture, but there is controversy about the optimal surgical approach anterior, posterior or combined approach. Objectives: To assess the efficacy & safety of anterolateral approach in decompression and reconstruction with spinal instrumentation for lumbar burst fractures. Subjects & Methods: A retrospective study including 16 patients, 10 males and 6 females with lumbar burst fractures and anterior compression treated operatively by anterolateral approach for corpectomy and single level fusion by using expandable cage or mesh cage loaded with bone graft and plat with screws. The clinical and radiological follow up after discharge from the hospital ranged from 12 to 24 months. Results: All patients improved regarding the Frankel score more than one grade after surgery, except 2 cases of grade A didn’t improve. Mean preoperative visual analogue scale was 7.4 improving to 0.9 postoperatively. The mean Local kyphosis improved from 8.8° before surgery to -1° after surgery. Conclusions: Anterolateral approach is feasible, effective, and safe approach for unstable lumbar burst fractures. Angular deformity is successfully corrected when the anterior approach is used.

关键词： Burst Fracture

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Urinary neutrophil gelatinase-associated lipocalin(NGAL)and serum cystatin C measurements for early diagnosis of acute kidney injury in children admitted to PICU

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World Journal of Pediatrics 2018年第2期14卷 134-142页

作者： Jameela Abdulaziz Kari mohamed Ahmed Shalaby Kholoud Sofyani Ahmad Saleh Sanad Albaraa Fuad Ossra Rayan Smeer Halabi Maha Hassan Aljuhani wael Mohammad Toffaha Feras Aymen Moria Samar Sabry Hanan AbdelAziz Ahmed Khalid Abdulaziz Alhasan Sara Sharief Osama Safdar Pediatric Nephrology Center of Excellence and Department of Pediatrics King Abdulaziz University80215Jeddah 21589Kingdom of Saudi Arabia Pediatric Intensive Care Unit Department of PediatricsKing Abdulaziz UniversityJeddahKingdom of Saudi Arabia Pediatric Department Cairo UniversityGizaEgypt Department of Pediatrics College of MedicineKing Khalid University HospitalKing Saud UniversityRiyadhKingdom of Saudi Arabia

Background Acute kidney injury(AKI)is common in critically ill children with significant mortality and *** creatinine is an insensitive and late biomarker compared to newly proposed AKI *** Prospective study in pediatric intensive care unit(PICU)over three months to compare between serum cystatin-C(s-Cys-C)and urinary neutrophil gelatinase-associated lipocalin(uNGAL)as AKI biomarkers at multiple time points with pediatric risk,injury,failure,loss,end-stage renal disease(pRIFLE)classification in diagnosing *** Forty children were *** these 40 children,22 developed AKI according to pRIFLE *** was no significant difference between AKI and non-AKI in age(P=0.29).Post cardiac surgery,renal insult was the main cause of AKI(27.3%).There was a twofold increased risk of incident AKI in those patients with high baseline uNGAL at PICU admission and almost a fourfold increased risk in patients with high baseline s-Cys-C at PICU *** levels were highly predictive of AKI during the follow-up period[area under the curve(AUC)=0.76,95%confidence interval(CI)0.61-0.92].The cutoff point with the highest correctly classified proportion was 223 ng/mL(≥12 centiles)which correctly predict 80.0%patients with AKI,with a corresponding sensitivity of 72.7%and a specificity of 89.9%.AUC for s-Cys-C was 0.86(95%CI 0.75-0.97),and the highest correctly classified proportion was 1009μg/L(≥13 centiles);75%of patients with AKI,with a corresponding sensitivity of 63.6%and a specificity of 88.9%.Conclusion uNGAL and s-Cys-C predicts AKI early in critically ill children.

关键词： Acute kidney injury Neutrophil gelatinase-associated lipocalin Serum cystatin C

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Twist Drill Evacuation of Chronic Subdural Hematoma in Comorbid Patients

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Open Journal of Modern Neurosurgery 2019年第4期9卷 379-392页

作者： Salma R. Abdel-Hamid Radwan Nouby wael M. A. Al-Ghani mohamed A. Ragaee Neurosurgery Department Assuit University Hospital Assuit Egypt

Chronic Subdural Hematoma (CSDH) is one of the most common types of intracranial hemorrhage, and the prognosis is good if treated properly. The standard treatment for CSDH is surgical evacuation. Various surgical procedures are used such as burr holes evacuation, twist-drill craniostomy, and craniotomy. Our aim is to evaluate the feasibility and safety of twist dill as a first-choice treatment in evacuation of CSDH in comorbid patients. Methods: This study is a prospective analysis of CSDH evacuation using two twist drill craniostomy holes and irrigation conducted on 21 patients with different comorbidities in Assuit University Hospital between May 2017 and May 2018. Results: The overall postoperative clinical improvement was 95.2%. The operative time was less than 10 minutes in 71.4% of the patients. 4 patients showed residual collection in the post-operative CT (19%). Pneumocephaly was detected in 2 patients (9.5%). Postoperative seizures occurred in 2 patients (9.5%), and subarachnoid hemorrhage was detected in one patient (4.7%). Conclusion: This approach is a new modification of twist drill craniostomy which can decrease the postoperative residual and recurrence rates and also still a minimally invasive and lifesaving technique in patients with different comorbidities.

关键词： Chronic Subdural Hematoma Twist Drill Craniostomy Minimally Invasive Neurosurgery

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Powder Metallurgical Fabrication and Microstructural Investigations of Aluminum/Steel Functionally Graded Material

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Materials Sciences and Applications 2011年第12期2卷 1708-1718页

作者： Mahmoud M. Nemat-Alla Moataz H. Ata mohamed R. Bayoumi wael Khair-Eldeen 不详

Aluminum/steel electric transition joints (ETJs) are used in aluminum reduction cell for the purpose of welding aluminum rod and steel bracket components. Solid state welding process used for joining aluminum and steel at the electric transition joints have the drawbacks of cracking and separation at the interface surfaces. Cracking and separation at the electric transition joints are caused by the stress singularities that developed due to the mismatch in thermal and mechanical properties of each material. To overcome the drawback of electric transition joints, aluminum/steel functionally graded may be used as electric transition joints or proposed. Therefore manufacturing and investigation of aluminum/steel functionally graded materials fabricated by powder metallurgy process were carried out through the current work. Different samples with different layers of aluminum/steel functionally graded materials were compacted using steel die and punch at the same compacted pressure and sintered temperature. After investigating the different samples of aluminum/steel functionally graded materials under different fabrication conditions, the suitable fabrication regime was determined with the aid of microscopic observations.

关键词： Powder Metallurgy Functionally Graded Materials Aluminum/Steel Electric Transition Joint Microstructural Investigations

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A New Thioamide Derivative for Separation and Preconcentration of Multi Elements in Aquatic Environment by Cloud Point Extraction

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American Journal of Analytical Chemistry 2011年第6期2卷 697-709页

作者： mohamed M. Hassanien Ali M. Hassan wael I. Mortada Ahmed A. El-Asmy 不详

2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results.

关键词： Heavy Metals Preconcentration Cloud Point Extraction 2-(Pyridine-2-Yl)-N-P-Chlorohydrazinecarbothioamide

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