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Chinese Physics C 2024年第4期48卷 6-13页

作者： Y.mahmoud H.Abdallah m.t.hussein S.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the CmS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 teV and an integrated luminosity of 11.6 fb−1.these data were gathered from the CmS open data.Dark matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.thus,the search was conducted in the dimuon plus large missing transverse momentum channel.One benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CmS open data.No evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CmS open data search for new physics dark fermion

Search for dark matter production in association with the Z′ boson at the LHC in pp collisions at √s=8 teV using monte Carlo simulations

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Chinese Physics C 2021年第8期45卷 1-11页

作者： S.Elgammal m.A.Louka A.Y.Ellithi m.t.hussein Centre for theoretical physics The British University in EgyptCairoEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

this analysis evaluates the possibility of the search for Dark matter(Dm)particles using events with a Zf heavy gauge boson and a large missing transverse momentum at the Large Hadron Collider(LHC).We consider the muonic decay of Z'.the analyzed monte Carlo samples were the Open simulated files produced by the Compact muon Solenoid(CmS)collaboration for proton-proton collisions,corresponding to an integrated luminosity of the LHC run-I with 19.7 fb^(-1) at √s=8 teV.two scenarios,namely a simplified benchmark scenario,called Dark Higgs,and the effective field theory(EFt)formalism,were used for interpretations.Limits were set on Z′,dark matter masses,and the cutoff scale of the EFt.

关键词： dark matter new heavy gauge boson Large Hadron Collider Compact muon Solenoid

Chiral phase structure of the sixteen meson states in the SU(3) Polyakov linear-sigma model for finite temperature and chemical potential in a strong magnetic field

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Chinese Physics C 2019年第3期43卷 56-71页

作者： Abdel Nasser tawfik Abdel magied Diab m.t.hussein Nile University Juhayna sq.of 26th-July-Corridor16453 GizaEgypt Frankfurt Institute for Advanced Studies Ruth Moufang Str.160438 FrankfurtGermany and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Egyptian Center for theoretical Physics(ECtP) MTI University11571 CairoEgypt and World Laboratory for Cosmology And Particle Physics(WLCAPP)11571 CairoEgypt Physics Department Faculty of ScienceCairo University12613 GizaEgypt

In characterizing the chiral phase-structure of pseudoscalar(J^(pc) = 0^(-+)), scalar(J^(pc) = 0^(++)), vector(J^(pc) =1^(--)) and axial-vector(J^(pc) = 1^(++)t) meson states and their dependence on temperature, chemical potential, and magnetic field,we utilize the SU(3) Polyakov linear-sigma model(PLSm) in the mean-field approximation. We first determine the chiral(non)strange quark condensates,σ_l and σ_s, and the corresponding deconfinement order parameters, φ and φ~*, in thermal and dense(finite chemical potential) medium and finite magnetic field. the temperature and the chemical potential characteristics of nonet meson states normalized to the lowest bosonic matsubara frequency are analyzed. We note that all normalized meson masses become temperature independent at different critical temperatures. We observe that the chiral and deconfinement phase transitions are shifted to lower quasicritical temperatures with increasing chemical potential and magnetic field. thus, we conclude that the magnetic field seems to have almost the same effect as the chemical potential, especially on accelerating the phase transition, i.e. inverse magnetic catalysis. We also find that increasing the chemical potential enhances the mass degeneracy of the various meson masses, while increasing the magnetic field seems to reduce the critical chemical potential, at which the chiral phase transition takes place. Our mass spectrum calculations agree well with the recent PDG compilations and PNJL, lattice QCD calculations, and QmD/UrQmD simulations.

关键词： Chiral transition magnetic fields magnetic catalysis critical temperature viscous properties of QGP

Near-zero stiffness accelerometer with buckling of tunable electrothermal microbeams

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microsystems & Nanoengineering 2024年第2期10卷 67-81页

作者： hussein hussein Chen Wang Rui Amendoeira Esteves michael Kraft Hossein Fariborzi Department of mechanical Engineering MSFEAAmerican University of BeirutBeirut11072020Lebanon King Abdullah University of Science and technology Thuwal23955-6900Saudi Arabia ESAt-mNS University of Leuven3001LeuvenBelgium

Pre-shaped microbeams,curved or inclined,are widely used in mEmS for their interesting stiffness properties.these mechanisms allow a wide range of positive and negative stiffness tuning in their direction of motion.A mechanism of pre-shaped beams with opposite curvature,connected in a parallel configuration,can be electrothermally tuned to reach a near-zero or negative stiffness behavior at the as-fabricated position.the simple structure helps incorporate the tunable spring mechanism in different designs for accelerometers,even with different transduction technologies.the sensitivity of the accelerometer can be considerably increased or tuned for different applications by electrothermally changing the stiffness of the spring mechanism.Opposite inclined beams are implemented in a capacitive micromachined accelerometer.the measurements on fabricated prototypes showed more than 55 times gain in sensitivity compared to their initial sensitivity.the experiments showed promising results in enhancing the resolution of acceleration sensing and the potential to reach unprecedent performance in micromachined accelerometers.

关键词： properties. mechanism. stiffness

Does local vaginal estrogen after tension-free transobturator vaginal tape reduce overactive bladder symptoms in postmenopausal women? A prospective randomized, controlled study

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Asian Journal of Urology 2024年第1期11卷 86-92页

作者： Samer mahmoud morsy Dalia Farouk Sara Hassan Ahmed Yehia Abdelaziz hussein Aly hussein Urology Department Kasr Al Ainy HospitalCairo UniversityCairoEgypt Obstetrics and Gynecology Department Kasr Al Ainy HospitalCairo UniversityCairoEgypt

Objective:We aimed to evaluate the efficacy of topical estrogen after transvaginal tension-free vaginal tape-obturator(tVt-O)in the treatment of de novo overactive bladder symptoms that appear after surgery.methods:this is a prospective randomized controlled study performed in the Urology and Gynecology Departments,Kasr Al Ainy Hospital,Cairo University,Cairo,Egypt.two hundred and ten postmenopausal females presenting during the period between January 2017 and November 2020 with stress urinary incontinence were included in the study.Patients were divided into two groups,105 patients in Group A(treatment group)and 105 patients in Group B(control group).Patients in Group A underwent transvaginal tVt-O followed by local vaginal estrogen treatment for 6 months,while patients in Group B underwent transvaginal tVt-O only.the study included any postmenopausal female with urodynamic stress urinary incontinence.All patients had to fulfill a 3-day bladder diary,overactive bladder symptoms score,urine analysis,urodynamic study,and post-voiding residual urine measurement by abdominal ultrasound preoperatively and at 3-month and 6-month follow-ups.Results:At 6-month follow-up,daytime frequency was reduced to 8%in Group A(increased to 21%in Group B)with a statistically significant difference between both groups(p=0.009).At 6-month follow-up,nocturia was 8%in Group A(11%in Group B)with no statistically significant difference between both groups(p=0.469).there was a statistically significant difference between both groups as regards to urinary urgency at 6-month follow-up(p=0.024).there was a statistically significant difference in postoperative wound healing events as regards to cure,hyperemia,gapping,and wound infection 1 week after intervention between both groups(p=0.008).No local or systemic side-effects were reported from local estrogen use.Conclusion:Local vaginal estrogen treatment given to postmenopausal patients after midurethral sling procedures can reduce the symptoms of daytime frequency and urinary urgency.Long-ter

关键词： Stressurinary incontinence Estrogen midurethral sling Overactive bladder symptom

Cellular preconditioning and mesenchymal stem cell ferroptosis

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World Journal of Stem Cells 2024年第2期16卷 64-69页

作者： Doaa hussein Zineldeen mazhar mushtaq Khawaja Husnain Haider Basic Sciences Sulaiman AlRajhi UniversityAlbukairiyah 52736AlQaseemSaudi Arabia Department of medical Biochemistry and molecular Biology Faculty of MedicineTanta UniversityTanta 6632110Egypt

In this editorial,we comment on the article published in the recent issue of the World Journal of Stem Cells.they focus on stem cell preconditioning to prevent ferroptosis by modulating the cystathionineγ-lyase/hydrogen sulfide(H_(2)S)pathway as a novel approach to treat vascular disorders,particularly pulmonary hypertension.Preconditioned stem cells are gaining popularity in regenerative medicine due to their unique ability to survive by resisting the harsh,unfavorable microenvironment of the injured tissue.they also secrete various paracrine factors against apoptosis,necrosis,and ferroptosis to enhance cell survival.Ferroptosis,a regulated form of cell death characterized by iron accumulation and oxidative stress,has been implicated in various pathologies encompassing dege-nerative disorders to cancer.the lipid peroxidation cascade initiates and sustains ferroptosis,generating many reactive oxygen species that attack and damage multiple cellular structures.Understanding these intertwined mechanisms provi-des significant insights into developing therapeutic modalities for ferroptosis-related diseases.this editorial primarily discusses stem cell preconditioning in modulating ferroptosis,focusing on the cystathionase gamma/H_(2)S ferroptosis pathway.Ferroptosis presents a significant challenge in mesenchymal stem cell(mSC)-based therapies;hence,the emerging role of H_(2)S/cystathionase gamma/H_(2) S signaling in abrogating ferroptosis provides a novel option for therapeutic intervention.Further research into understanding the precise mechanisms of H_(2)S-mediated cytoprotection against ferroptosis is warranted to enhance the thera-peutic potential of mSCs in clinical settings,particularly vascular disorders.

关键词： Cell survival Cell therapy Hydrogen sulfide Ferroptosis Preconditioning Stem cells Umbilical cord

Hepatic recompensation according to Baveno VII criteria via transjugular intrahepatic portosystemic shunt

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World Journal of Gastroenterology 2024年第12期30卷 1777-1779页

作者： Hossam Eldin Shaaban Abeer Abdellatef hussein Hassan Okasha Department of Internal medicine and Gastroenterology NHTMRICairo 11796Egypt Department of Internal medicine Division of Gastroenterology and HepatologyKasr Al-Aini School of MedicineCairo UniversityCairo 11562Egypt

transjugular intrahepatic portosystemic shunt is a therapeutic modality done through interventional radiology.It is aimed to decrease portal pressure in special situations for patients with decompensated liver disease with portal hypertension.It represents a potential addition to the therapeutic modalities that could achieve hepatic recompensation in those patients based on Baveno VII criteria.

关键词： Decompensated liver cirrhosis Hepatic recompensation Baveno VII Portal hypertension

A reinforcement learning approach for thermostat setpoint preference learning

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Building Simulation 2024年第1期17卷 131-146页

作者： hussein Elehwany mohamed Ouf Burak Gunay Nunzio Cotrufo Jean-Simon Venne Department of Environmental Engineering Carleton UniversityOttawaCanada Departmentof Building Civiland Environmental EngineeringConcordia UniversityMontrealCanada BrainBox Al Inc. MontrealCanada

Occupant-centric controls(OcC)is an indoor climate control approach whereby occupant feedback is used in the sequence of operation of building energy systems.While OcC has been used in a wide range of building applications,an OcC category that has received considerable research interest is learning occupants'thermal preferences through their thermostat interactions and adapting temperature setpoints accordingly.many recent studies used reinforcement learning(RL)as an agent for OcC to optimize energy use and occupant comfort.these studies depended on predicted mean vote(PmV)models or constant comfort ranges to represent comfort,while only few of them used thermostat interactions.this paper addresses this gap by introducing a new off-policy reinforcement learning(RL)algorithm that imitates the occupant behaviour by utilizing unsolicited occupant thermostat overrides.the algorithm is tested with a number of synthetically generated occupant behaviour models implemented via the Python APl of EnergyPlus.the simulation results indicate that the RL algorithm could rapidly learn preferences for all tested occupant behaviour scenarios with minimal exploration events.While substantial energy savings were observed with most occupant scenarios,the impact on the energy savings varied depending on occupants'preferences and thermostat use behaviour stochasticity.

关键词： reinforcement learning preference learning occupant-centric controls smart thermostats off-policy learning

Novel design of a compact tunable dual band wireless power transfer(tDB-WPt)system for multiple WPt applications

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Frontiers of Information technology & Electronic Engineering 2024年第4期25卷 616-628页

作者： Hany A.AtALLAH Rasha hussein AHmED Adel B.ABDEL-RAHmAN Department of Communications and Electronics Faculty of EngineeringSouth Valley UniversityQena 83523Egypt Egypt-Japan University of Science and technology Alexandria 21934Egypt

In this study we present the design and realization of a tunable dual band wireless power transfer(tDB-WPt)coupled resonator system.the frequency response of the tunable band can be controlled using a surface-mounted varactor.the transmitter(tx)and the receiver(Rx)circuits are symmetric.the top layer contains a feed line with an impedance of 50Ω.two identical half rings defected ground structures(HR-DGSs)are loaded on the bottom using a varactor diode.We propose a solution for restricted WPt systems working at a single band application according to the operating frequency.the effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were studied.to validate the simulation results,the proposed tDB-WPt system was fabricated and tested.the system occupied a space of 40 mm×40 mm.It can deliver power to the receiver with an average coupling efficiency of 98%at the tuned band from 817 to 1018 mHz and an efficiency of 95%at a fixed band of 1.6 GHz at a significant transmission distance of 22 mm.the results of the measurements accorded well with those of an equivalent model and the simulation.

关键词： Defected ground structure(DGS) Surface-mounted tunable dual band wireless power transfer(tDB-WPt) Varactor

tuning the optoelectronic properties for small organic compounds as organic solar cell applications

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Optoelectronics Letters 2024年第7期20卷 412-417页

作者： hussein K.mejbel Lafy F.Al-Badry Department of Physics College of Education for Pure Science University of Thi-Qar Department of Physics College of Science University of Thi-Qar

Recently, organic solar cells have attracted the attention of many researchers owing to flexibility, low cost, light weight and large-area applications, and significant improvement in the power conversion efficiency（PCE）. In this work, we designed chains from organic compounds as donors and replaced the core unit in each series with a variety of acceptors in order to enhance their optical and electronic characterization and performance for power conversion efficiencies in organic solar cells. We utilized density functional theory（DFt） and time-dependent density functional theory（tD-DFt） to investigate the geometry optimization by using the Gaussian 09 program. Both electronic and optical properties were determined, which involve the lowest unoccupied molecular orbital（LUmO） and the highest occupied molecular orbital（HOmO） levels, the band gap energy, maximum absorption wavelength(λmax), open circuit voltage(Voc), and light harvesting efficiency（LHE）. Our evaluation denotes that the small compounds suggested are predicted to exhibit the best performance compared to the first series（SC1）, like a lower band gap energy, a lower HOmO energy level, a greater absorption range, and a larger PCE.

关键词： A