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燃料化学学报 2013年第2期41卷 214-222页

作者： hussein abou-yousef El Barbary Hassan Philip Steele Department of Forest Products Mississippi State University Cellulose & Paper Department National Research CenterDokkiCairoEgypt

Direct conversion of cellulose into 5-hydroxymethylfurfural(HMF) was performed by using single or combined metal chloride catalysts in 1-ethyl-3-methylimidazolium chloride(Cl) ionic *** study demonstrated formation of 2-furyl hydroxymethyl ketone(FHMK),and furfural(FF) simultaneously with the formation of *** reaction parameters were addressed to optimize yields of furan derivatives produced from cellulose by varying reaction temperature,time,and the type of metal chloride *** reaction by using FeCl3 resulted in 59.9% total yield of furan derivatives(HMF,FHMK,and FF) from ***3 was the most effective catalyst for selective conversion of cellulose into HMF(35.6%) with less concentrations of FHMK,and *** the yields of furans produced from cellulose could be achieved via reactions catalyzed by different combinations of two metal *** optimization was carried out to produce total furans yield 75.9% by using FeCl3/CuCl2 ***3/CuCl2 was the most selective combination to convert cellulose into HMF(39.9%) with total yield(63.8%) of furans produced from the *** temperature and time of the catalytic reaction played an important role in cellulose conversion,and the yields of *** the reaction temperature could enhance the cellulose conversion and HMF yield for short reaction time intervals(5~20 min).

关键词：化学动力学燃料化学理论 EMIM HMF

Preparation and Characterization of Eco-friendly Carboxymethyl Cellulose Antimicrobial Nanocomposite Hydrogels

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Journal of Renewable Materials 2018年第5期6卷 536-547页

作者： Sawsan Dacrory hussein abou-yousef Ragab E.abou-Zeid Samir Kamel Mohamed S.Abdel-Aziz Mohamed Elbadry Cellulose and Paper Department National Research Centre33 El Buhouth St.DokkiGiza 12622Egypt Microbial Chemistry Department National Research Centre33 El Buhouth St.DokkiGiza 12622Egypt Department of Chemistry Faculty of ScienceAin Shams UniversityAbbassiaCairo 11566Egypt

Carboxymethyl cellulose hydrogels were developed through crosslinking process using eco-friendly crosslinkers such as maleic,succinic,and citric *** cellulose was prepared from the cellulosic fraction of olive industry residues.A series of hydrogels with varying crosslinker acid concentrations,reaction times,and reaction temperatures was produced to study the swelling capacities and gel fraction of the obtained *** study pertains to the preparation of antimicrobial nanocomposite hydrogels through in-situ incorporation of the silver nanoparticles during the crosslinking *** nanoparticles were prepared by reduction of AgNO3 with leaves of Ricinus *** particle size of prepared silver nanoparticles was detected by transmission electron microscopy(TEM).Chemical structure and morphological characterizations of the prepared hydrogels were performed using Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and energy-dispersive X-ray spectroscopy(EDX).Finally,the antimicrobial activity of the loaded silver hydrogels against Gram negative(G-ve),Gram positive(G+ve),and Candida albicans yeast was demonstrated.

关键词： Hydrogel crosslinked carboxymethyl cellulose silver nanoparticles antibacterial activity

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 *** 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 *** simple structure helps incorporate the tunable spring mechanism in different designs for accelerometers,even with different transduction *** sensitivity of the accelerometer can be considerably increased or tuned for different applications by electrothermally changing the stiffness of the spring *** inclined beams are implemented in a capacitive micromachined *** measurements on fabricated prototypes showed more than 55 times gain in sensitivity compared to their initial *** 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

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 *** 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 *** recent studies used reinforcement learning(RL)as an agent for OcC to optimize energy use and occupant *** studies depended on predicted mean vote(PMV)models or constant comfort ranges to represent comfort,while only few of them used thermostat *** paper addresses this gap by introducing a new off-policy reinforcement learning(RL)algorithm that imitates the occupant behaviour by utilizing unsolicited occupant thermostat *** algorithm is tested with a number of synthetically generated occupant behaviour models implemented via the Python APl of *** simulation results indicate that the RL algorithm could rapidly learn preferences for all tested occupant behaviour scenarios with minimal exploration *** 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 *** frequency response of the tunable band can be controlled using a surface-mounted *** transmitter(Tx)and the receiver(Rx)circuits are *** 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 *** propose a solution for restricted WPT systems working at a single band application according to the operating *** effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were *** validate the simulation results,the proposed TDB-WPT system was fabricated and *** system occupied a space of 40 mm×40 *** 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 *** 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

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 ***:This is a prospective randomized controlled study performed in the Urology and Gynecology Departments,Kasr Al Ainy Hospital,Cairo University,Cairo,*** hundred and ten postmenopausal females presenting during the period between January 2017 and November 2020 with stress urinary incontinence were included in the *** 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 *** study included any postmenopausal female with urodynamic stress urinary *** 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 ***: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 ***:Local vaginal estrogen treatment given to postmenopausal patients after midurethral sling procedures can reduce the symptoms o

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 *** 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 *** stem cells are gaining popularity in regenerative medicine due to their unique ability to survive by resisting the harsh,unfavorable microenvironment of the injured *** also secrete various paracrine factors against apoptosis,necrosis,and ferroptosis to enhance cell ***,a regulated form of cell death characterized by iron accumulation and oxidative stress,has been implicated in various pathologies encompassing dege-nerative disorders to *** lipid peroxidation cascade initiates and sustains ferroptosis,generating many reactive oxygen species that attack and damage multiple cellular *** these intertwined mechanisms provi-des significant insights into developing therapeutic modalities for ferroptosis-related *** editorial primarily discusses stem cell preconditioning in modulating ferroptosis,focusing on the cystathionase gamma/H_(2)S 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 *** 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

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(λ;max;), open circuit voltage(V;oc;), 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

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 *** is aimed to decrease portal pressure in special situations for patients with decompensated liver disease with portal *** 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

Search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using CMS open data

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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−*** data were gathered from the CMS open *** 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 *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CMS open *** 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