203 research outputs found
Real-Time AMPC for Loss Reduction in 48 V Six-Phase Synchronous Motor Drives
No full textThis article presents an adaptive model predictive control (AMPC) algorithm for real-time management of a six-phase permanent magnet synchronous motor. The system optimizes both speed control and power dissipation, featuring an automated power derating mechanism for overload conditions. AMPC demonstrated advantages over traditional field-oriented control, including reduced losses and lower energy consumption, while maintaining robust performance and high speed control precision. Validation through hardware-in-the-loop testing on the dSPACE platform confirmed its effectiveness. The contribution focuses on enhanced stability, robustness, and integrating predictive features to further improve efficiency and adaptability in electric drive systems. © 2025 The Author(s). IET Power Electronics published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology
Management Strategies of Patients with Neuromyelitis Optica Spectrum Disorder During the COVID-19 Pandemic Era
No full textSherif M Hamdy, Maged Abdel-Naseer, Hatem S Shehata, Nevin M Shalaby, Amr Hassan, Alaa Elmazny, Ehab Shaker, Mona AF Nada, Sandra M Ahmed, Mohamed I Hegazy, Husam S Mourad, Ahmed Abdelalim, Rehab Magdy, Alshimaa S Othman, Doaa A Mekkawy, Nirmeen A Kishk Neurology Department, Faculty of Medicine, Cairo University, Cairo, EgyptCorrespondence: Alaa Elmazny 66-Manial-Street, Cairo, EgyptTel +966536012237Email [email protected]: The ongoing coronavirus (COVID-19) pandemic is a global health emergency of international concern and has affected management plans of many autoimmune disorders. Immunosuppressive and immunomodulatory therapies are pivotal in the management of neuromyelitis optica spectrum disorder (NMOSD), potentially placing patients at an increased risk of contracting infections such as COVID-19. The optimal management strategy of NMOSD during the COVID-19 era remains unclear. Here, however, we examined the evidence of NMOSD disease-modifying therapies (DMTs) use during the present period and highlighted different scenarios including treatment of relapses as well as initiation and maintenance of DMTs in order to optimize care of NMOSD patients in the COVID-19 era.Keywords: neuromyelitis optica spectrum disorder, COVID-19, pandemi
Surgical Management of Ipsilateral Fracture of the Femur and Tibia in Adults (the Floating Knee): Postoperative Clinical, Radiological, and Functional Outcomes
No full textWave Feedforward Control for Large Floating Wind Turbines
No full textFloating wind energy has attracted substantial interest since it enables the deployment of renewable wind energy in deeper waters. However, floating wind turbines are subjected to disturbances, predominantly from turbulence in the wind and waves hitting the platform. Wave disturbances cause undesired oscillations in speed and increase structural loading. This paper focuses on mitigating these disturbance effects with feedforward control using knowledge of the incoming wavefield. The control problem is formulated in an H∞ optimization framework designing two wave feedforward controllers: one to reduce rotor speed oscillations, and the other one to minimize the platform pitch motion. Mid-fidelity time-domain simulations demonstrate the improved performance of the proposed control algorithm regarding wave disturbance mitigation at the cost of higher actuator duty.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Team Jan-Willem van WingerdenShip Hydromechanics and Structure
Characteristics and predictors of progression in an Egyptian multiple sclerosis cohort: a multicenter registry study
No full textSherif M Hamdy,1 Maged Abdel-Naseer,1 Nevin M Shalaby,1 Alaa N Elmazny,1 Ahmed A Nemr,2 Amr Hassan,1 Mohamed I Hegazy,1 Husam S Mourad,1 Nirmeen A Kishk,1 Mona A Nada,1 Ahmed Abdelalim,1 Amr M Fouad,1 Hatem S Shehata1 1Neurology Department, Cairo University, 2Neurology Department, Maadi Military Hospital, Cairo, Egypt Background: Multiple sclerosis (MS) is a complex autoimmune disease with a heterogeneous presentation and diverse disease course. Recent studies indicate a rising prevalence of MS in the Middle East.Objective: To characterize the demographics and disease features of Egyptian patients attending four tertiary referral MS centers in Cairo.Materials and methods: This was a retrospective, observational study on 1,581 patients between 2001 and 2015. Medical records were reviewed and data were identified and extracted in a standardized electronic registry.Results: The mean age of disease onset was 26.6±7.8 years, with the majority being female (2.11:1). Relapsing–remitting MS was the most common type (75.1%). The main presenting symptom was motor weakness (43.9%), which was also the most frequent symptom during the disease course. Family history of MS was found in 2.28%. Higher initial Expanded Disability Status Scale score, black holes, and infratentorial lesions on initial magnetic resonance imaging were independent factors for disease progression by univariate analysis (OR 3.87 [95% CI 1.84–6.51], 4.14 [95% CI 3.08–5.58], 4.07 [95% CI 3.21–4.99], respectively); however, in multivariate analysis, only infratentorial lesions were an independent risk for disease progression (OR 6, 95% CI 2.99–12.02; P=0.0005).Conclusion: The results from this registry – the largest for MS in the Arab region to date – are comparable to other registries with slight differences. Keywords: multiple sclerosis, MS registry, epidemiology, Middle East, North Africa, Egypt 
Effects of Three Different Fibrates on Intrahepatic Cholestasis Experimentally Induced in Rats
No full textBackground. Activation of PPARα modulates cholesterol metabolism and suppresses bile acid synthesis. This study aims to evaluate the effect of PPARα agonists, fenofibrate, bezafibrate, and gemfibrozil, on acute cholestasis induced by ethinylestradiol (EE) plus chlorpromazine (CPZ) in rats. Method. 100 male albino rats (150–200 gm) were divided randomly into 10 equal groups. Control group received 1% methylcellulose vehicle; disease group received CPZ plus EE for 5 consecutive days; four groups received either ursodeoxycholic acid, fenofibrate, bezafibrate, or gemfibrozil for 7 days; 2 days before EE + CPZ, three other groups received one of the three fibrates after GW6471, a selective PPARα antagonist in addition to EE + CPZ. The final group received GW6471 alone. Results. The three fibrates showed marked reduction () in serum levels of ALP, GGT, ALT, AST, total bile acids, bilirubin, TNFα, and IL-1β and in hepatic malondialdehyde level as well as a significant increase in bile flow rate () in addition to improvements in histopathological parameters compared to diseased group. In groups which received GW6471, these effects were completely abolished with fenofibrate and partially blocked with bezafibrate and gemfibrozil. Conclusion. Short-term administration of fibrates to EE/CPZ-induced intrahepatic cholestatic rats exerted beneficial effects on hepatocellular damage and apoptosis. Fenofibrate anticholestatic effect was solely PPARα dependent while other mechanisms played part in bezafibrate and gemfibrozil actions
A BLACK WIDOW OPTIMIZATION ALGORITHM FOR SOLVING KENKEN PROBLEM
No full textAbstract:
Kenken is the most famous kind of arithmetic and grid puzzle. Kenken is a grid puzzle like Sudoku. In Kenken, the main objective is to fill cells from 1 to n×n grid on the condition that the mathematical operation on every cage is achieved, so that the main constraint in the kenken problem is to produce a certain “target” number when combined using a specified mathematical operation {+, -, ×, ÷}, under this condition, every number appears once on every column and row. The grids range in size from 3×3 to 9×9. KenKen is a new puzzle phenomenon that’s sweeping the world educational, and fun, KenKen is a great way to exercise your brain and sharpen your mathematical tools at the same time. In this paper, the proposed research used python programming to solve the kenken puzzle by using a heuristic search and a black widow optimization algorithm. The proposed algorithm depends on a heuristic search that used logic rules. A lot of puzzle cases cannot be solved, then the black widow optimization algorithm will be run. Obtained results show the efficiency that the proposed algorithm in grids ranges in size 5×5, 7×7, and 9×9 are more efficient than the old ones
Evaluation of ERG-11 gene expression in azole resistant Candida isolates from various clinical specimens in ICUs
No full textBackground: Candida infection is considered one of the most dangerous infections in intensive care unit patients (ICU). Resistance to azoles is a major challenging condition in treating candida infections. Mutations or overexpression of the ERG 11 gene may contribute to azoles resistance. Methods: This prospective study evaluated 300 clinical samples including sputum, blood, urine, wound swabs, and pus obtained from different ICU patients. Different candida species were identified phenotypically by conventional methods and biochemical analysis by API 20 C kit (api® Candida) and confirmed by VITEK 2 compact system using identification yeast ID-YST cards. Antifungal susceptibility testing was performed using the VITEK 2 compact system followed by detection of ERG11-2 gene overexpression by RT-PCR in azoles resistant candida species. Results: A total of 165 candida species were detected from 300 clinical samples. C. albicans was identified in 59.4%. Most of C. albicans and non albicans were isolated from sputum samples. Only 17% of the overall isolated Candida species were resistant to fluconazole while 5% were resistant to voriconazole. Overexpression of the ERG11 gene was detected only in 10 isolates. Conclusion: Increased ERG11 gene expression may be one of the leading causes of azoles resistance among candida species in ICU patients.Background:Candida infection is considered one of the most dangerous infections in intensive care unit patients (ICU). Resistance to azoles is a major challenging condition in treating candida infections. Mutations or overexpression of the ERG11 gene may contribute to azoles resistance. Methods: This prospective study evaluated 300 clinical samples including sputum, blood, urine, wound swabs, and pus obtained from different ICU patients. Different candida species were identified phenotypically by conventional methods and biochemical analysis by API 20 C kit (api® Candida) and confirmed by VITEK 2 compact system using identification yeast ID-YST cards. Antifungal susceptibility testing was performed using the VITEK 2 compact system followed by detection of ERG11-2 gene overexpression by RT-PCR in azoles resistant candida species.Results: A total of 165 candida species were detected from 300 clinical samples. Candida albicans (C. albicans) was identified in 59.4%. Most of C. albicans and non albicans were isolated from sputum samples. Only 17% of the overall isolated Candida species were resistant to fluconazole while 5% were resistant to voriconazole. Overexpression of the ERG11 gene was detected only in 10 isolates. Conclusion: Increased ERG11 gene expression may be one of the leading causes of azoles resistance among candida species in ICU patients
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