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A Model for a Dual Universe

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Journal of high Energy Physics, Gravitation and Cosmology 2024年第1期10卷 52-66页

作者： Tharwat mahmoud El-Sherbini Physics Department Faculty of Science Cairo University Cairo Egypt

A model for a dual universe is proposed, based on the assumption that simultaneously with our universe an anti-matter counterpart was initiated immediately following the Big Bang. At the heart of the model is a primordial anti-particle that differentiates itself from its counterpart, a previously hypothesized S-particle responsible for the formation of our own universe, through its course of rotation. The angular rotation of the anti-particle, in accordance with space-time rotation, together with the counter rotation of the S-particle, resulted in a time difference in the formation processes of both universes and consequently led to a large distance between the spatial locations occupied by our universe and its dual counterpart in the same space-time continuum. The existence of this anti-matter universe might solve the present mystery of matter anti-matter asymmetry and thus explain why hardly any free anti-matter can be observed in our universe. Moreover, the model implicates the possibility of the presence of a repulsive gravitational force exerted by the clusters of anti-particles in the anti-matter universe upon our universe. The repulsive gravitational force from the clusters of antiparticles in the dual universe as a whole upon our universe is completely different from the electrostatic repulsive force between similarly charged particles. It is also different from that due to possible gravitational or anti-gravitational interaction between individual matter and antimatter or particle and its antiparticle that might violate the CPT invariance, the theory of general relativity or the law of energy conservation. It is rather, a kind of negative gravity that affects our universe as a whole, due to the opposite course of rotation of the dual anti-universe relative to ours. The effect of this opposite rotation of the dual universe can cause anti-gravitational waves that penetrate our universe interacting with the space-time mesh around the galaxies in our universe a

关键词： Cosmology Antimatter high Energy Astrophysics Particle Physics

Insulin therapy in type 2 diabetes: Insights into clinical efficacy, patient-reported outcomes, and adherence challenges

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World Journal of Diabetes 2024年第5期15卷 828-852页

作者： mahmoud Emad-Eldin Gehan F Balata Eman A Elshorbagy Mona S hamed Mohamed S Attia Department of Pharmacy Practice Faculty of PharmacyZagazig UniversityZagazig HFQM+872Al-Sharqia GovernorateEgypt Department of Pharmacy Practice Faculty of PharmacyHeliopolis UniversityCairo 44519Egypt Department of Pharmaceutics Faculty of PharmacyZagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt Department of Internal Medicine Faculty of MedicineZagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt Department of Community at Faculty of Medicine Zagazig UniversityZagazig 44519Al-Sharqia GovernorateEgypt

Insulin therapy plays a crucial role in the management of type 2 diabetes as the disease *** the past century,insulin formulations have undergone significant modifications and bioengineering,resulting in a diverse range of available insulin *** products show distinct pharmacokinetic and pharmacodynamic ***,various insulin regimens have em-erged for the management of type 2 diabetes,including premixed formulations and combinations of basal and bolus *** utilization of different insulin regimens yields disparate clinical outcomes,adverse events,and,notably,patient-reported outcomes(PROs).PROs provide valuable insights from the patient’s perspective,serving as a valuable mine of information for enhancing healthcare and informing clinical *** to insulin therapy,a critical patient-reported outcome,significantly affects clinical outcomes and is influenced by multiple *** review provides insights into the clinical effectiveness of various insulin preparations,PROs,and factors impacting insulin therapy adherence,with the aim of enhancing healthcare practices and informing clinical decisions for individuals with type 2 diabetes.

关键词： Adherence Diabetes Insulin Patient-reported outcomes Pharmacokinetic Pharmacodynamic

Effects of friction stir processing and nano-hydroxyapatite on the microstructure,hardness,degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications

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Journal of Magnesium and Alloys 2024年第1期12卷 209-224页

作者： Bo Wu Farazila Yusof Fuguo Li huan Miao A.R.Bushroa Mohd Ridha Bin Muhamad Irfan Anjum Badruddin mahmoud Z.Ibrahim Department of Mechanical Engineering Faculty of EngineeringUniversiti MalayaKuala Lumpur 50603Malaysia Centre of Advanced Manufacturing and Material Processing(AMMP Centre) Universiti MalayaKuala Lumpur 50603Malaysia Center of Foundation studies in Science Universiti MalayaKuala Lumpur 50603Malaysia State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Mechanical Engineering Department College of EngineeringKing Khalid UniversityAbha 61421Saudi Arabia Design and Production Engineering Faculty of EngineeringAin Shams UniversityCairo 11517Egypt

Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural ***,the rapid degradation of magnesium alloys in biological media hinders successful *** of microstructure,as well as reinforcement particles can significantly improve the degradation *** this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n hA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were *** subsequent FSP passes of WE43 alloy and WE43/n hA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three *** resulted in increasing the microhardness by 120%(90.86 hV0.1)and 135%(105.59 hV0.1)for the WE43 and WE43-n hA,*** is found that increasing FSP passes improved the uniform distribution of n hA particles within the composite matrix which led to improved corrosion resistance and less degradation *** corrosion rate of the FSPed WE43/n hA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n ***,the growing Ca-P and Mg(Oh)2layer formed on the surface represented a protective layer that reduced the degradation *** wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base ***,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n hA composite after three *** results raise that the grain refinement by FSP and introduction of n hA partic

关键词： Friction stir processing Magnesium-based composite Nano-hydroxyapatite Corrosion behavior In-vitro bioactivity

Performance Comparison of hyper-V and KVM for Cryptographic Tasks in Cloud Computing

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Computers, Materials & Continua 2024年第2期78卷 2023-2045页

作者： Nader Abdel Karim Osama A.Khashan Waleed K.Abdulraheem Moutaz Alazab hasan Kanaker mahmoud E.Farfoura Mohammad Alshinwan Department of Intelligent Systems Faculty of Artificial IntelligenceAl-Balqa Applied UniversityAl-Salt1705Jordan Research and Innovation Centers Rabdan AcademyP.O.Box 114646Abu DhabiUnited Arab Emirates Department of Information Systems and Networks TheWorld Islamic Sciences and Education UniversityAmman11947Jordan Department of Cyber Security Isra UniversityAmman1162Jordan Faculty of Science and Information Technology Al-Zaytoonah University of JordanAmman11733Jordan Middle East University Research Unit Middle East UniversityAmman11831Jordan

As the extensive use of cloud computing raises questions about the security of any personal data stored there,cryptography is being used more frequently as a security tool to protect data confidentiality and privacy in the cloud environment.A hypervisor is a virtualization software used in cloud hosting to divide and allocate resources on various pieces of *** choice of hypervisor can significantly impact the performance of cryptographic operations in the cloud *** important issue that must be carefully examined is that no hypervisor is completely superior in terms of performance;Each hypervisor should be examined to meet specific *** main objective of this study is to provide accurate results to compare the performance of hyper-V and Kernel-based Virtual Machine(KVM)while implementing different cryptographic algorithms to guide cloud service providers and end users in choosing the most suitable hypervisor for their cryptographic *** study evaluated the efficiency of two hypervisors,hyper-V and KVM,in implementing six cryptographic algorithms:Rivest,Shamir,Adleman(RSA),Advanced Encryption Standard(AES),Triple Data Encryption Standard(TripleDES),Carlisle Adams and Stafford Tavares(CAST-128),BLOWFISh,and *** study’s findings show that KVM outperforms hyper-V,with 12.2%less Central Processing Unit(CPU)use and 12.95%less time overall for encryption and decryption operations with various file *** study’s findings emphasize how crucial it is to pick a hypervisor that is appropriate for cryptographic needs in a cloud environment,which could assist both cloud service providers and end *** research may focus more on how various hypervisors perform while handling cryptographic workloads.

关键词： Cloud computing performance virtualization hypervisors hyper-V KVM cryptographic algorithm

Role of high-density brines in reservoir development stages:A review

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Energy Geoscience

Energy Geoscience 2024年第3期5卷 13-23页

作者： Arshad Raza Mohamed mahmoud Saad Alafnan Muhammad Arif Farzain Ud Din Kirmani Muhammad Shahzad Kamal Mobeen Murtaza Azeem Rana College of Petroleum Engineering and Geosciences(CPG) Petroleum Engineering DepartmentKing Fahd University of Petroleum&Minerals(KFUPM)DhahranSaudi Arabia Petroleum Engineering Department Khalifa UniversityAbu Dhabi127788United Arab Emirates Department of Petroleum and Gas Engineering N.F.C.Institute of Engineering&TechnologyMultanPakistan Center for Integrative Petroleum Research King Fahd University of Petroleum&Minerals31261DhahranSaudi Arabia Department of Chemistry University of Management and TechnologyLahorePakistan

high-density brines have been recognized beneficial for oilfield applications,with various key areas such as drilling,completion and formation ***-density brines can play a critical role in the development and production of oil and gas reservoirs during the primary,secondary,and tertiary recovery ***-density brines can enhance the mobility and recovery of the oil in the reservoir by controlling the density and ***,a less attention has been given to the application of high-density brine in the area of reservoir *** review is shedding light on a concise overview of reservoir development stages in association with the recovery *** addition,most possible applications of high-density fluids have also been reviewed in the field of the reservoir *** summary,this review state that high-density brines can be used to stimulate reservoirs by hydraulic fracturing during the primary recovery ***,the risk of increased interfacial tension,which relies on the density difference of two fluids,can trap more residual oil relative to conventional water *** addition,high-density brines are effective in decreasing the mobility ratio and facilitating favorable displacement during polymer ***,they can be least effective in alkaline flooding due to the high IFT related to large density ***,it is suggested to consider the utilization of sustainable high-density brines by taking into account effective factors in petroleum engineering aspects such as stimulation,secondary recovery and polymer flooding.

关键词： Reservoir development Brine high density Environment Sustainability

A hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa F.Soliman Fatma E.Fadl-Allah Walid El-Shafai mahmoud I.Aly Maali Alabdulhafith Fathi E.Abd El-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier Frequency Division Multiple Access(SC-FDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-FDMA systemas an adopted communication *** introduces a robust image communication framework over SC-FDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-FDMA *** linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-FDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Gas diffusion in catalyst layer of flow cell for CO_(2) electroreduction toward C_(2+) products

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Nano Research 2024年第3期17卷 1101-1106页

作者： Xiqing Wang Qin Chen Yajiao Zhou Yao Tan Ye Wang hongmei Li Yu Chen mahmoud Sayed Ramadan A.Geioushy Nageh K.Allam Junwei Fu Yifei Sun Min Liu hunan Joint International Research Center for Carbon Dioxide Resource Utilization School of Physics and ElectronicsCentral South UniversityChangsha 410083China School of Energy and Power Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China Central Metallurgical Research and Development Institute(CMRDI) P.O.Box 87Helwan 11421CairoEgypt Energy Materials Laboratory School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt Research Center for Advanced Energy and Carbon Neutrality Beihang UniversityBeijing 100191China

The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))*** this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)*** gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/h_(2)O supply for high C_(2+)*** a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/h_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.

关键词： gas diffusion electrode CO_(2)reduction Cu mass transfer C_(2)product

Childhood asthma biomarkers including zinc: An exploratory crosssectional study

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World Journal of Clinical Pediatrics 2024年第1期13卷 31-40页

作者： hoda Atef Abdelsattar Ibrahim Mona Mohsen Boles Salep Aziz hanna Dina mahmoud Khaled Mohamed Abdelhamid El-Khashab Pediatric Clinical Nutrition Unit Faculty of MedicineCairo UniversityCairo 12613Egypt Department of Pediatrics Faculty of MedicineCairo UniversityCairo 12613Egypt Department of Clinical Pathology Faculty of MedicineCairo UniversityCairo 12613Egypt

BACKGROUND Childhood bronchial asthma(BA)is a chronic inflammatory respiratory *** conditions,including zinc deficiency,can affect such allergic *** To outline the difference in serum zinc levels between asthmatic children and healthy *** A cross-sectional study was carried out at Children’s hospital,Cairo University,investigating serum zinc levels in children with BA(n=40)and healthy children(n=21).Other markers included serum ferritin,iron,hemoglobin(hb),and immunoglobulin E(IgE)*** t-tests and Mann-Whinny tests were used for *** Kruskal-Wallis test was applied to compare serum ferritin and IgE levels with regard to asthma ***'s rank correlation was performed to explore the relationship between serum ferritin levels and both iron and hb levels in asthmatic *** Children with BA had higher levels of zinc,yet the difference was not significant(P=0.115).Serum ferritin and IgE levels were significantly higher in asthmatic children(P=0.006 and 0.001,respectively),yet their levels did not differ significantly by severity(P=0.623 and 0.126,respectively).There was a nonsignificant weak correlation between serum ferritin levels and both serum iron and hb *** Serum zinc levels do not seem to differ between asthmatic children and healthy *** ferritin levels may be a marker of asthma *** IgE levels are not markers of asthma severity.

关键词： Children Asthma Zinc Ferritin

Obstructive sleep apnea-hypopnea syndrome immunological relationship

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World Journal of Clinical Cases 2024年第27期12卷 6011-6014页

作者： mahmoud Ali Alaa Ramadan Salim Surani Department of Medicine Al-Azhar UniversityDamietta 11651Egypt Department of Medicine South Valley UniversityQena 83523Egypt Department of Medicine and Pharmacology Texas A&M UniversityCollege StationTX 77843United States Department of Anesthesiology Mayo ClinicRochesterMN 55905United States

Obstructive sleep apnea-hypopnea syndrome(OSAhS)is a complex disorder cha-racterized by symptoms resulting from intermittent hypoxia and hypopnea,with research indicating a crucial role of immune system dysregulation and genetic variations in its pathogenesis.A recent Zhao et al study utilizes Mendelian ran-domization analysis to explore the causal relationship between immune cell characteristics and *** study identifies specific lymphocyte subsets as-sociated with OSAhS,providing valuable insights into the disease's pathophy-siology and potential targets for therapeutic *** findings underscore the significance of genetic and immunological factors in sleep disorders,offering a fresh perspective on OSAhS's *** to existing literature,Zhao et al's study stands out for its focus on genetic markers and specific immune responses associated with OSAhS,expanding upon previous research primarily centered on systemic *** conclusion,the study represents a signi-ficant advancement in the field,shedding light on the causal role of immune cells in OSAhS and paving the way for future research and targeted treatments.

关键词： Obstructive sleep apnea Mendelian randomization Lymphocyte charac-teristics Immunology Obstructive sleep apnea-hypopnea syndrome