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Recent Techniques in Management of Lumbosacral Region Tumours: A Prospective Comparative Study

Open Journal of Modern Neurosurgery 2018年第2期8卷 239-249页

作者： Mostafa abd Elsamea Mohamed Shaaban ahmed Taha Department of Neurosurgery Al-Azhar University Hospital Damietta Egypt

Background: The lumbosacral plexus consists of the ventral rami from the L2 to S3 nerve roots, with some additions from the L1 and S4 nerve roots as well. The standard treatment for spinal cord compression is urgent surgically decompressive laminectomy over the affected level with resection as much as possible of the exposed tumor to relieve the cord compression. We aim to correlate the impact of preoperative clinical picture, duration of symptoms, and the pathological nature of the lumbo-sacral spine tumors on the outcome of comparative study different modalities of management. Patients and Methods: During the period between 2015 and 2017, thirty cases were studied and surgically managed in Al-Azhar University Hospital, Damietta. Cases were selected for surgery if they were diagnosed as having a symptomatizing lumbosacral lesion. Results: Thirty patients were included in the current study;the commonest lesion in this study was ependymoma eight patients (27%), astrocytoma six patients (20%), and meningioma five patients (17%). Nerve sheath tumor comprised five cases (17%) with the hemangioblastomas three cases (10%), epidermoid one case (3%), and ependymoma of the filum terminale two cases (6%). The mean age of the included patients was 38.96 ± 15.42. The mean duration of lesions was 13.66 ± 10.93. They were 15 male patients (50%), and 15 female patients (50%), with male: female ratio 1:1. The mean duration of symptoms ranged for 1:60 months. The most common presenting manifestations were sensory followed by motor and sphinctric disturbance. Complications occurred in 8 patients (23%), and the most common was postoperative CSF leak. 19 out of 30 cases were surgically totally resected (63%), while 11 cases (37%) were grossly totally resected. Conclusions: Ependymoma and meningioma have more favorable outcome compared to other spinal tumors. Accurate and rapid diagnosis prior to surgery also associated with good outcome.

关键词： Lambosacral Lesion Astrocytoma Ependymoma

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Effective Mass Model Reduced to Ordinary Mass Using Newton’s, Quantum and Generalized Special Relativity

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Natural Science 2021年第9期13卷 398-406页

作者： Nagwa Idriss Ali ahmed Mohamed Idriss ahmed Mubarak Dirar abd-Alla Department of Physics Faculty of Science and Art (Dariah) Qassim University Almulid KSA Department of Physics and Mathematics Hantoub Faculty of Education Gezira University Hantoub Sudan Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan

The concept of the effective mass in crystals shows that the electron mass is affected by the crystal field and was experimentally verified. A useful expression for effective mass was obtained. Unfortunately this expression showed that the effective mass vanishes in the ab-sence of the external field. This is in conflict with observations which show that it reduces to the ordinary mass. To cure this defect a new model is developed assuming the existence of vacuum force as verified experimentally as shown by Casimir effect. Using Newton’s second law and the quantum expression of momentum, useful expressions were found. The same expression was found using generalized special relativity. Strikingly the three models reduced to the conventional one in the absence of vacuum, they also reduced to the ordinary electron mass in the absence of all forces.

关键词： Effective Mass Newton’s Second Quantum Momentum Generalized Special Relativity

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Resource Exhaustion Attack Detection Scheme for WLAN Using Artificial Neural Network

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Computers, Materials & Continua 2023年第3期74卷 5607-5623页

作者： abdallah Elhigazi abdallah Mosab Hamdan Shukor abd Razak Fuad A.Ghalib Muzaffar Hamzah Suleman Khan Siddiq ahmed Babikir Ali Mutaz H.H.Khairi Sayeed Salih Faculty of Engineering Future UniversityKhartoum 10553Sudan Faculty of Computing and Informatics Universiti Malaysia SabahKota Kinabalu88400Malaysia Information Assurance and Security Research School of ComputingUniversiti Teknologi MalaysiaJohor81310Malaysia School of Psychology and Computer Science University of Central LancashirePreston PR12HEUK Deaptement of Management Information Systems College of Administrative ScienceApplied Science UniversityAl Eker623Bahrain Deaptement of Information Technology College of Computer and Information SciencesKing Saud UniversityRiyadh11461Saudi Arabia

IEEE 802.11 Wi-Fi networks are prone to many denial of service(DoS)attacks due to vulnerabilities at the media access control(MAC)layer of the 802.11 *** to the data transmission nature of the wireless local area network(WLAN)through radio waves,its communication is exposed to the possibility of being attacked by illegitimate ***,the security design of the wireless structure is vulnerable to versatile *** example,the attacker can imitate genuine features,rendering classificationbased methods inaccurate in differentiating between real and false *** security standards have been proposed over the last decades to overcome many wireless network attacks,effectively detecting such attacks is crucial in today’s real-world *** paper presents a novel resource exhaustion attack detection scheme(READS)to detect resource exhaustion attacks *** proposed scheme can differentiate between the genuine and fake management frames in the early stages of the attack such that access points can effectively mitigate the consequences of the *** scheme is built through learning from clustered samples using artificial neural networks to identify the genuine and rogue resource exhaustion management frames effectively and efficiently in *** proposed scheme consists of four modules whichmake it capable to alleviates the attack impact more effectively than the related *** experimental results show the effectiveness of the proposed technique by gaining an 89.11%improvement compared to the existing works in terms of detection.

关键词： 802.11 media access control(MAC) wireless local area network(WLAN) artificial neural network denial-of-service(DoS)

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Nuclear Matrix Protein-22 and Telomerase Reverse Transcriptase Are Diagnostic Markers for Bladder Carcinoma in Egypt

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Journal of Cancer Therapy 2011年第5期2卷 646-653页

作者： Amel abd Allah Hashim Mahmoud Youns ahmed abd Al-rahman Soltan Sahar abd El-mohsen Ali 不详

Bladder carcinoma is the foremost oncologic problem among males in Egypt. Here, we evaluated the possible diagnostic value of the urinary Nuclear Matrix Protein-22 “NMP-22” and Telomerase Reverse Transcriptase “hTERT” among histological subtypes of bladder cancer. 120 males with non-muscle invasive bladder cancer, 21 non malignant bladder conditions and 21 healthy volunteers were included in this study. Estimation of hTERT and NMP-22 was done by PCR-ELISA and ELISA, respectively, from voided urine and results were compared to those of urine cytology. Results showed that urinary hTERT and NMP-22 were significantly higher in all cancer patients compared to control group. NMP-22 was able to discriminate between transitional cell bladder carcinoma “TCC” patients and squamous cell bladder carcinoma “SqCC” ones. Both markers succeded to discriminate between some transitional cell bladder carcinoma grades. Additionally, hTERT discriminated between some Tumor stages in both TCC and SqCC. Our results demonstrated that urinary hTERT and NMP-22 could be efficient urinary markers for the differential diagnosis of bladder cancer.

关键词： Bladder Cancer Urinary Markers NMP-22 hTERT

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New Approach for the Synthesis of Pyrano[2,3-d]- thiazoles

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材料科学与工程（中英文A版） 2011年第5X期1卷 705-710页

作者： Mohamed Sayed abd-Elaal Elgay Shaban Ibrahim Mohamed Hassan ahmed Eyada Tarek ahmed abd-El-Aziz Gameel ahmed Mohamed El-hag All Department of Chemistry Faculty of Science Al-Azhar University in Assiut Assiut 71524 Egypt Technology Engineering Institute Tamoh Giza Egypt Department of Chemistry Faculty of Science Al-Azhar University Nasr City Cairo Egypt

The structure of 2-carboxamidomethylene-4-thiazolidinone 1 has two active methylene groups: one is endocyclic and close the carbonyl group, where the other is branched at position 2 and close to endocyclic amino group. Thus, the reactivity of compound 1 towards arylidenemalononitrile and ethyl α-cyanocinnamates as electrophiles was studied. Consequently, a new route to the synthesis of pyrano[2,3-d]thiazoles 4a-d and 7a-d has been developed through heterocyclization of carboxamidomethylene -4-thiazolidinone 1 with some α-cyanocinnmonitriles derivatives.

关键词：噻唑啉酮吡喃酮合成氨基酸化合物衍生物羰基环和

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Assessment and Distribution of Heavy Metals Pollutants in Manzala Lake, Egypt

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Journal of Geoscience and Environment Protection 2015年第6期3卷 107-122页

作者： Mahmoud abd El-Kawy Zahran Yasser ahmed El-Amier abdelhamid ahmed Elnaggar Hoda abd El-Azim Mohamed Muhammad abd El-Hady El-Alfy Botany Department Faculty of Science Mansoura University Mansoura Egypt Soils Department Faculty of Agriculture Mansoura University Mansoura Egypt Marine Pollution Department National Institute of Oceanography and Fisheries Suez Egypt

Contamination with heavy metals is one of the most serious problems in the aquatic environments. In Egypt, Manzala Lake is suffering from this problem. The objective of this work was to assess heavy metals pollutants and their spatial distribution in Manzala Lake using GIS technique. Georeferenced water and sediment samples were randomly collected from the lake. The detected heavy metals were: Fe, Pb, Cu, Cd, Cr, Zn and Co. The obtained results indicated that the highest concentrations of heavy metals were observed in the northeastern and the southern parts of the lake nearby drains. This could be attributed to industrial, agricultural and municipal wastes coming through the drains especially Bahr El-Baqar drain and the industrial wastes coming from Port Said drains. From the geo-accumulation index, it was noticed that the lake is more polluted with cadmium and lead in the hydrosoils samples. All metals in water are within the EPA standard limit except for cadmium. Geostatistics provides effective methods to quantify the contaminated waters and sediments which support decision-making about redevelopment scenarios or remediation techniques.

关键词： Manzala Lake Heavy Metals Indices Pollution GIS

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Characterization and Impact of Cattle Manure Particle Size on Physical Properties of Sandy Soils

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Journal of Geoscience and Environment Protection 2019年第8期7卷 180-194页

作者： Doaa ahmed El-Nagar Ramadan abd Alaaty Mohamed Soil Improvement Department Soil Water and Environment Institute (Agricultural Research Center) Egypt Vegetable Crops Department Horticulture Research Institute (Agricultural Research Center) Egypt

Sandy soils have poor physical properties, which cause them to drain quickly and not hold water well;however, with the addition of cattle manure, sandy soil can be improved. Therefore, experiments were conducted to investigate the characterization and impact of different particle sizes of cattle manure (CMS) on improving some physical properties of sandy soil and thus the yield of lettuce. Cattle manure was ground to powder and was sieved with three different Particle sizes 4.76-2 (CMS1), 2-0.8 (CMS2), 0.8-0.4 (CMS3) mm. Some physical properties were measured for different Particle sizes of manure. A batch of sorption experiments was carried out to study the role of different Particle sizes of manure on adsorption of N, P and K from aqueous solution. Two experiments were carried out on sandy soil (pots and field) to study the impact of adding CMS (5 ton/fed) to enhance some physical properties of sandy soil. The results indicated that the physical properties of cattle manure changed based on particle size fractionation, where Bulk density and saturated water holding capacity increased as particle size decreased, while porosity reduced as particle size decreased. The results of the sorption parameters of N, P and K on different particle sizes of manure indicated that maximum sorption occurred on CMS 3 for both P and K according to Langmuir and Freundlich sorption models. Two experiments showed that CMS had affected significantly the total porosity (TP), bulk density (Bd), slowly drainable pores (SDP), water holding pores and (WHP) available water (AW) in comparison to control. The CMS had a slight effect on Quickly-drainable pores (QDP) and fine capillary pores (FCP) as compared to the control in both experiments. Fresh weight, dry weight and number of leaf lettuce increased significantly with decreasing particle sizes of cattle manure as compared to control.

关键词： Cattle Manure Size Soil Properties Langmuir and Freundlich Sorption Models

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The Influence of Welding Parameters on Brittle Fracture of Liquefied Natural Gas Storage Tank Welded Joint

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Materials Sciences and Applications 2013年第3期4卷 198-204页

作者： abd El Fattah Mustafa Khourshid Mohamed ahmed Ghanem Production Engineering and Mechanical Design Department Faculty of Engineering Tanta University Tanta Egypt.

Many applications operate at sufficiently low temperature conditions where most structural steels become very brittle and, therefore, unsuitable for use in safety-critical structures. So the materials used in the vessels or storage tanks which keep the natural gas at liquefaction temperatures need to remain ductile and crack resistant with a high level of safety. The material also needs to have high strength in order to reduce the wall thickness of the container and it must permit welding without any risk of brittle fracture. 9% Ni steel plates are one of most common used materials in the LNG storage tank application. However, the welding procedure for 9% Ni steel plates requires high level of skills of welding that is strictly controlled welding parameter for balancing avoidance of cold and hot cracking and maintenance of high strength. Mechanical properties are important characteristics of the weldment that must confirm to the application feasibility as well as functional requirements of the welded joint. The only way to enhanced the mechanical properties of welded joint by controlling the parameters of using welding process. From the main variables of the arc welding process are the heat input and interpass temperature where the two variables control the thermal cycle of welding process. The experiment show that for thin test specimen with thickness ≤ 14 mm, the heat input range from 1.4 to 2 KJ/mm and controlling interpass temperature within 80°C give high tensile strength with improving the toughness properties of welded joint and reduce the probability of brittle fracture happened by increase the ductility and reduce the yield strength and increased the transition temperature.

关键词： 9% Ni Steel Plate LNG Tank Heat Input Mechanical Properties Welding Process and Brittle Fracture

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Assessment of Remotely Sensed Digital Elevation Models (DEMs) Compared with DGPS Elevation Data and Its Influence on Topographic Attributes

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Advances in Remote Sensing 2018年第2期7卷 144-162页

作者： Moawad Badawy Moawad ahmed Omar abd El Aziz Department of Geography Faculty of Arts Ain Shams University Cairo Egypt Parsons Corporations Riyadh Saudi Arabia

Accuracy and quality of DEM are of a great interest for a wide range of applications. In this study, quality of ASTER GDEM and SRTM DEMs were assessed in comparison with DGPS measurements. Impact of DEM resolution upon the accuracy of terrain representation and topographic attributes was also discussed. The study deduced that vertical error has a strong effect on error propagation and this highly obvious in higher elevations as the absolute standard error (SE) ranges between is ±0 - 2.5 and ±0 - 2.4 m for ASTER GDEM and SRTM respectively. This is reflected on slope and aspect as the vertical errors increase and uncertainty is relatively high in flat and low areas. Error propagation in low lands influenced drainage extraction and resulted in isolated and truncated water courses.

关键词： SRTM ASTER GDEM RTK System Error Assessment Topographic Attributes

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Using of <i>In-Situ</i>Mercury Film Sensor Hyphenated with Affinity Voltammetry for High Throughput Drug-Protein Binding Studies

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American Journal of Analytical Chemistry 2013年第4期4卷 159-165页

作者： ahmed K. Youssef Deia abd El-Hady Chemistry Department Faculty of Science Assiut University Assiut Egypt

A new simple and reliable in-situ mercury film sensor coupled with affinity differential pulse stripping voltammetry (ADSPV) or affinity cyclic voltammetry (ACV) was investigated. The interaction of fenoprofen with bovine serum albumin (BSA) onto the proposed electrochemical sensor was studied. The nature of the electrochemical process of fenoprofen by cyclic voltammetry was depicted. Reproducibility of the proposed method was checked giving a precision of 0.073 standard deviation. The limit of detection and limit of quantification were 7.0 and 22.0 nmol/L, respectively. Fenoprofen was interacted with BSA by 1:1 stoichiometry to form electroinactive supramolecular complex. The binding constant was precisely estimated by non-linear regression analysis based on the shifting of analyte peak potentials. The proposed experiments and data analysis could be used to investigate the drug-protein binding constant within a short analysis time compared to other chromatographic techniques.

关键词： Sensor Affinity Voltammetry Fenoprofen Bovine Serum Albumin Binding Constant

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