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Impact of transjugular intrahepatic porto-systemic shunt on post liver transplantation outcomes: Study based on the United Network for Organ Sharing database

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World Journal of Hepatology 2017年第2期9卷 99-105页

作者： Khalid mumtaz sherif metwally Rohan m modi Nishi Patel Dmitry Tumin Anthony J michaels James Hanje Ashraf el-Hinnawi Don Hayes Jr Sylvester m Black Wexner medical Center Gastroenterology Hepatology and Nutrition Division the Ohio State University Department of Internal medicine the Ohio State University Department of Pediatrics the Ohio State University Department of Surgery the Ohio State University Section of Pulmonary medicine the Ohio State University

AImTo determine the impact of transjugular intrahepatic porto-systemic shunt (TIPS) on post liver transplantation (LT) outcomes. mETHODSUtilizing the United Network for Organ Sharing (UNOS) database, we compared patients who underwent LT from 2002 to 2013 who had underwent TIPS to those without TIPS for the management of ascites while on the LT waitlist. The impact of TIPS on 30-d mortality, length of stay (LOS), and need for re-LT were studied. For evaluation of mean differences between baseline characteristics for patients with and without TIPS, we used unpaired t-tests for continuous measures and χ2 tests for categorical measures. We estimated the impact of TIPS on each of the outcome measures. multivariate analyses were conducted on the study population to explore the effect of TIPS on 30-d mortality post-LT, need for re-LT and LOS. All covariates were included in logistic regression analysis. RESULTSWe included adult patients (age ≥ 18 years) who underwent LT from may 2002 to September 2013. Only those undergoing TIPS after listing and before liver transplant were included in the TIPS group. We excluded patients with variceal bleeding within two weeks of listing for LT and those listed for acute liver failure or hepatocellular carcinoma. Of 114770 LT in the UNOS database, 32783 (28.5%) met inclusion criteria. Of these 1366 (4.2%) had TIPS between the time of listing and LT. We found that TIPS increased the days on waitlist (408 ± 553 d) as compared to those without TIPS (183 ± 330 d), P P P = 0.001) by TIPS to LOS. CONCLUSIONTIPS did increase time on waitlist for LT. more importantly, TIPS was not associated with 30-d mortality and re-LT, but it did lengthen hospital LOS after transplantation.

关键词： Transjugular intrahepatic porto-systemic shunt Shunt Liver Transplantation Ascites model for end-stage liver disease mortality Transjugular

Influence of Nanocrystalline ZrO<sub>2</sub>Additives on the Fracture Toughness and Hardness of Spark Plasma Activated Sintered WC/ZrO<sub>2</sub>Nanocomposites Obtained by mechanical mixing method

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Open Journal of Composite materials 2012年第1期2卷 1-7页

作者： m. sherif el-Eskandarany Hesham m. A. Soliman m. Omoric 不详

The present study reports the formation of ultrafine hard particles of nanocomposite WC with different additions of ZrO2 powders (0.5 - 20 vol.%). The initial mixed powders of WC with the desired ZrO2 concentrations were mechanically mixed for 360 ks (end-product) under argon gas atmosphere at room temperature, using high energy ball mill. The end-product consists of average grain size of about 17 nm in diameter. The obtained nanocomposite powders were consolidated into fully dense compact, using spark plasma sintering (SPS) technique in vacuum. The experimental results revealed that the consolidation step, which was conducted at 1673 K with uniaxial pressure ranging from 19.6 to 38.2 mPa for short time (0.18 ks), does not lead to dramatic grain growth in the powders so that the consolidated nanocomposite bulk objects maintain their nanocrystalline behavior, being fine grains with an average size of 63 nm in diameter. The relative densities of consolidated nanocomposite WC/ZrO2 materials increase from 99.1% for WC-0.5% ZrO2 to 99.93% for WC-20% ZrO2. The indentation fracture toughness of the composites can be tailored between 7.31 and 19.46 mPa/m1/2 by controlling the volume fraction of ZrO2 matrix from 0.5% to 20%. The results show that the Poisson’s ratio increased monotonically with increasing the ZrO2 concentrations to get a maximum value of 0.268 for WC-20% ZrO2. In the whole range of ZrO2 concentrations (0.5 - 20 vol.%), high hardness values (20.73 to 22.83 GPa) were achieved. The Young’s modulus tends to decrease with increasing the volume fraction of the ZrO2 matrix to reach a minimum value of 583.2 GPa for WC-20% ZrO2. These hard and tough WC/ZrO2 nanocomposites are proposed to be employed as higher abrasive-wear resistant materials.

关键词： Nanocomposite Tungsten Carbide Zirconia Spark Plasma Sintering Powder metallurgy mechanical Alloying microstructure SEm HRTEm

Fault Diagnosis in Robot manipulators Using SVm and KNN

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Intelligent Automation & Soft Computing 2023年第2期35卷 1957-1969页

作者： D.maincer Y.Benmahamed m.mansour mosleh Alharthi sherif S.m.Ghonein Laboratoire de Robotiques Parallélisme et Systèmes Embarquer Département Automatique et ControlUniversitédes Sciences et Technologie Houari BoumedieneAlgiersAlgeria Laboratoire de Recherche en electrotechnique Ecole Nationale PolytechniqueB.P 182El-Harrach16200AlgiersAlgeria electrical Engineering Department College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

In this paper,Support Vector machine(SVm)and K-Nearest Neighbor(KNN)based methods are to be applied on fault diagnosis in a robot manipulator.A comparative study between the two classiﬁers in terms of successfully detecting and isolating the seven classes of sensor faults is considered in this *** both classiﬁers,the torque,the position and the speed of the manipulator have been employed as the input ***,it is to mention that a large database is needed and used for the training and testing *** SVm method used in this paper is based on the Gaussian kernel with the parametersγand the penalty margin parameter“C”,which were adjusted via the PSO algorithm to achieve a maximum accuracy *** were carried out on the model of a Selective Compliance Assembly Robot Arm(SCARA)robot manipulator,and the results showed that the Particle Swarm Optimization(PSO)increased the per-formance of the SVm algorithm with the 96.95%accuracy while the KNN algo-rithm achieved a correlation up to 94.62%.These results showed that the SVm algorithm with PSO was more precise than the KNN algorithm when was used in fault diagnosis on a robot manipulator.

关键词： Support Vector machine(SVm) Particle Swarm Optimization(PSO) K-Nearest Neighbor(KNN) fault diagnosis manipulator robot(SCARA)

Beta-endorphin in serum and seminal plasma in infertile men

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Asian Journal of Andrology 2006年第6期8卷 709-712页

作者： Shawky el-Haggar Salah el-Ashmawy Ahmed Attia Taymour mostafa m.m.Farid Roaiah Ashraf Fayez sherif Ghazi Wael Zohdy Nagwa Roshdy Andrology Department Clinical Pathology Department medical Biochemistry Department Faculty of MedicineCairo UniversityCairo 12311Egypt

Aim： To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups. methods： Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay （elISA） method in 80 infertile men equally divided into four groups： non-obstructive azoospermia （NOA）, obstructive azoospermia （OA）, congenital bilateral absent vas deferens （CBVAD） and asthenozoospermia. The results were compared to those of 20 normozoospermic proven fertile men. Results： There was a decrease in the mean levels of betaendorphin in the seminal plasma of all successive infertile groups （mean ± SD： NOA 51.30 ± 27.37, OA 51.88 ± 9.47, CBAVD 20.36 ± 13.39, asthenozoospermia 49.26 ± 12.49 pg/mL, respectively） compared to the normozoospermic fertile control （87.23 ± 29.55 pg/mL）. This relation was not present in mean serum level of beta-endorphin between four infertile groups （51.09 ± 14.71, 49.76 ± 12.4, 33.96 ± 7.2, 69.1 ± 16.57 pg/mL, respectively） and the fertile control group （49.26 ± 31.32 pg/mL）. The CBVAD group showed the lowest seminal plasma mean level of beta-endorphin. Testicular contribution of seminal beta-endorphin was estimated to be approximately 40%. Seminal beta-endorphin showed significant correlation with the sperm concentration （r = 0.699, P = 0.0188） and nonsignificant correlation with its serum level （r = 0.375, P = 0.185） or with the sperm motility percentage （r = 0.470, P = 0.899）. Conclusion： The estimation of beta-endorphin alone is not conclusive to evaluate male reproduction as there are many other opiates acting at the hypothalamic pituitary gonadal axis.

关键词： azoospermia beta-endorphin male infertility opioid peptides semen seminal plasma

Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications

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Defence Technology（防务技术） 2023年第12期30卷 55-69页

作者： Ahmed Fahd Alex Baranovsky Charles Dubois Jamal Chaouki sherif elbasuney Shady Shokry Chemical Engineering Department Ecole Polytechnique de MontrealMontrealH3C 3A7Canada Energetic materials and Nanotechnology Research Center Technical Research CenterCairo11765Egypt mechanical and mechatronics Engineering Department University of WaterlooOntarioN2L 3G1Canada Head of Nanotechnology Research Center Military Technical CollegeCairo11767Egypt Laser and Optoelectronics Research Center Technical Research CenterCairo11765Egypt

Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNms) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNm content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TmD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TmD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.

关键词： Nanothermites Graphene oxide Reduced graphene oxide Carbon nano material Oxygenated salts Laser ignition Computational fluid dynamics

Classification of electroencephalogram Signals Using LSTm and SVm Based on Fast Walsh-Hadamard Transform

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Computers, materials & Continua 2023年第6期75卷 5271-5286页

作者： Saeed mohsen sherif S.m.Ghoneim mohammed S.Alzaidi Abdullah Alzahrani Ashraf mohamed Ali Hassan electronics and Communications Engineering Department Al-Madinah Higher Institute for Engineering and TechnologyGiza12947Egypt Department of Artificial Intelligence Engineering Faculty of Computer Science and EngineeringKing Salman International University(KSIU)South Sinai46511Egypt Department of electrical Engineering College of EngineeringTaif UniversityTaif21944Saudi Arabia Department of electronics and Communications Engineering October High Institute for Engineering and Technology6th of October CityGiza12596Egypt

Classification of electroencephalogram(EEG)signals for humans can be achieved via artificial intelligence(AI)***,the EEG signals associated with seizure epilepsy can be detected to distinguish between epileptic and non-epileptic *** this perspective,an automated AI technique with a digital processing method can be used to improve these *** paper proposes two classifiers:long short-term memory(LSTm)and support vector machine(SVm)for the classification of seizure and non-seizure EEG *** classifiers are applied to a public dataset,namely the University of Bonn,which consists of 2 classes–seizure and *** addition,a fast Walsh-Hadamard Transform(FWHT)technique is implemented to analyze the EEG signals within the recurrence space of the ***,Hadamard coefficients of the EEG signals are obtained via the ***,the FWHT is contributed to generate an efficient derivation of seizure EEG recordings from non-seizure EEG ***,a k-fold cross-validation technique is applied to validate the performance of the proposed *** LSTm classifier provides the best performance,with a testing accuracy of 99.00%.The training and testing loss rates for the LSTm are 0.0029 and 0.0602,respectively,while the weighted average precision,recall,and F1-score for the LSTm are 99.00%.The results of the SVm classifier in terms of accuracy,sensitivity,and specificity reached 91%,93.52%,and 91.3%,*** computational time consumed for the training of the LSTm and SVm is 2000 and 2500 s,*** results show that the LSTm classifier provides better performance than SVm in the classification of EEG ***,the proposed classifiers provide high classification accuracy compared to previously published classifiers.

关键词： electroencephalogram LSTm SVm fast Walsh-Hadamard transform seizure accuracy sensitivity specificity

Outcomes of liver transplantation in patients with hepatorenal syndrome

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World Journal of Hepatology 2016年第24期8卷 999-1011页

作者： Rohan m modi Nishi Patel sherif N metwally Khalid mumtaz Department of Internal medicine the Ohio State University Wexner Medical Center Department of Internal medicine Division of Gastroenterology Hepatology and Nutrition the Ohio State University Medical Center

Hepatorenal syndrome(HRS) plays an important role in patients with liver cirrhosis on the wait list for liver transplantation(LT). The 1 and 5-year probability of developing HRS in cirrhotic with ascites is 20% and 40%, respectively. In this article, we reviewed current concepts in HRS pathophysiology, guidelines for HRS diagnosis, effective treatment options presently available, and controversies surrounding liver alone vs simultaneous liver kidney transplant(SLKT) in transplant candidates. many treatment options including albumin, vasoconstrictors, renal replacement therapy, and eventual LT have remained a mainstay in the treatment of HRS. Unfortunately, even after aggressive measures such as terlipressin use, the rate of recovery is less than 50% of patients. moreover, current SLKT guidelines include:(1) estimation of glomerular filtration rate of 30 m L/min or less for 4-8 wk;(2) proteinuria > 2 g/d; or(3) biopsy proven interstitial fibrosis or glomerulosclerosis. Even with these updated criteria there is a lack of consistency regarding longterm benefits for SLKT vs LT alone. Finally, in regards to kidney dysfunction in the post-transplant setting, an estimation of glomerular filtration rate mL /min per 1.73 m2 may be associated with an increased risk of patients having long-term end stage renal disease. HRS is common in patients with cirrhosis and those on liver transplant waitlist. Prompt identification and therapy initiation in transplant candidates with HRS may improve post-transplantation outcomes. Future studies identifying optimal vasoconstrictor regimens, alternative therapies, and factors predictive of response to therapy are needed. The appropriate use of SLKT in patients with HRS remains controversial and requires further evidence by the transplant community.

关键词： Liver transplantation Simultaneous liver kidney transplantation Vasopressors Dialysis Posttransplant outcomes Hepatorenal syndrome

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

Postoperative Radiotherapy in Bladder Cancer Patients: 5-Year Institutional Experience of National Cancer Institute, Cairo University

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Journal of Cancer Therapy 2015年第7期6卷 579-593页

作者： Azza m. Nasr magda el mongi mamdouh Hagag manar m. moneer Hisham el Hossieny Azza Taher sherif magdy Radiation Oncology Department National Cancer Institute Cairo University Giza Egypt Clinical Oncology Department Faculty of Medicine Cairo University Giza Egypt Cancer Epidemiology and Biostatistics Department National Cancer Institute Cairo University Giza Egypt

Purpose: Adjuvant radiation therapy could reduce loco regional failure, but currently has no defined role because of previously reported morbidity. NCI-Cairo routine work is to give adjuvant PORT for locally advanced bladder carcinoma patients. The aim of this work is to re-evaluate this protocol regarding its effect on prognosis and complications. Patients and method: A retrospective study included 208 patients with pathologically proven bladder cancer who presented to the NCI, Cairo University from 2007-2011. All of them underwent RC with bilateral PLND followed by conventional post-operative radiotherapy in 2 - 6 weeks after surgery for 5000 cGy in 25 fractions, over 5 weeks using 2D technique. Analysis of data from their files was done for the treatment results, prognostic factors and complications. Results: Three years overall survival (OS) and disease free survival (DFS) for the whole group was ~60%, and 54% respectively in favour of the female gender, non-smokers, Squamous cell carcinoma patients, low grade tumours (grade 1 and 2) negative margins, N0, pT2b and early stage group showed the best prognoses. The 3 years metastases free survival (mFS) was ~71%. Only four factors showed a significant relation with the mFS which were the grade, LN status, T-stage and group staging. The local recurrence rate (LRC) at 2 years for the whole group was ~95% and 94% at 3 years. Only surgical margin status and extent of LN dissection had a significant impact on the LRC. Conclusions: Adjuvant radiotherapy shows sustained improvement in the loco regional control, and should be recommended for patients with locally advanced disease especially those with less than 10 dissected lymph nodes and those with positive margins.

关键词： Bladder Cancer Radiotherapy Pelvic Irradiation