MSA Repository "MSAR"

MSAR University's Digital Repository is a documentation and digitization of all university outcomes that are of effective value in the scientific and academic community and reflects the university's image, work, and effective contribution to society Through MSAR Digital Repository, the university managed to collect, store, archive and publish digital content - including documents, audio files, images and data sets - all in a safe place. MSAR is one of the strongest University Digital Repositories in Egypt and documented in the DSPACE community with its latest versions.

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    A novel technique for automatic hybrid modulation classification in UWA communications using 3D constellation diagrams
    (Nature Research, 2026-08-14) Mohamed A.Abdel-Moneim; Khalil F. Ramadan; El-Sayed M. El-Rabaie; Fathi E. Abd El-Samie; Nariman Abdel-Salam
    Underwater acoustic (UWA) communication systems operate in severe channel impairments, including strong multipath propagation, long delay spreads, frequency selectivity, Doppler effects, and high ambient noise. These challenges significantly complicate automatic modulation classification (AMC), especially in dense underwater networks where interference further degrades performance. In this paper, we investigate AMC for frequency-indexed three-dimensional hybrid modulation schemes, namely frequency-phase keying (FPK) and frequency quadrature amplitude modulation (FQAM), in UWA environments. While AMC has been extensively studied for conventional modulation formats, its application to frequency-indexed hybrid modulation schemes in UWA communication systems has received comparatively limited attention in the existing literature. The proposed approach depends on a three-dimensional (3D) constellation representation for robust feature extraction and modulation discrimination. The resulting 3D signal representations are converted into image-based inputs and processed with deep convolutional neural network (CNN) models, including AlexNet, VGG-19, and ResNet50, to automatically extract discriminative features and enable reliable classification. The proposed framework is evaluated under both single-carrier (SC) and orthogonal frequency-division multiplexing (OFDM) transmission schemes to comprehensively assess its robustness and adaptability. Simulation results demonstrate accurate modulation recognition under severe UWA conditions and low signal-to-noise ratio (SNR), confirming the effectiveness of combining hybrid modulation with deep-learning-based AMC for next-generation UWA communication systems.
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    Glycoconjugate strategy for GLUTdriven curcumin delivery and anticancer activity in breast cancer cells
    (Nature Research, 2026-08-14) Safaa S. Hassan; Fatma B. Rashidi; Ramy G. Seddik; Areej W. El-Sayed; Habiba A. Mohamed; Hager W. Mohamed; Menna M. Kenawy; Nouran B. Hussein; Nourhan A.Afify; Noura M. Megahed; Reem M. Zeinhom; Ziad A.Abdultawab; Ayatallah Elgohary; Nashwa Hamido; Ahmed I. Elwakil; Hadeel A.Alzoghaly; Martina O. Nabil; Ehab A.Ahmed; Khaled M. Ismail
    Selective targeting of cancer cells is a critical strategy in anticancer therapy, and the overexpression of glucose transporters (GLUTs) in malignant cells provides an attractive avenue for achieving this selectivity. In this study, we report the synthesis and biological evaluation of glycoconjugate vanadyl complexes as GLUT-directed anticancer agents against breast cancer. A Schiff base ligand (CG) was synthesized through the condensation of curcumin (C) and glucosamine (G), followed by complexation with vanadyl to form [VO(CG)₂]·5H₂O. The synthesized compounds were comprehensively characterized by elemental analysis, MS, NMR, FT-IR, TGA, molar conductance, and magnetic susceptibility measurements. Spectroscopic and computational studies confirmed that the ligand coordinates in a bidentate chelating mode via the azomethine nitrogen and the enolic oxygen. Biological evaluation in MCF-7 breast cancer cells included cytotoxicity assays, molecular docking, DNA-binding studies, and quantitative gene expression analysis. Both compounds exhibited cytotoxic activity, with the CG ligand showing the highest potency (IC₅₀ = 7.51 ± 0.12 μg/mL or 14.2 μM). Notably, co-treatment with the GLUT inhibitor quercetin significantly increased the IC₅₀ value, suggesting the involvement of GLUT-mediated cellular uptake. Molecular docking studies indicated favorable binding affinity toward GLUT, while DNA-binding experiments demonstrated interaction with DNA. Treatment of MCF-7 cells with the glycoconjugate ligand induced DNA damage, modulated the expression of cell cycle- and apoptosis-related genes, and promoted apoptosis. Flow cytometric analysis demonstrated that the glycoconjugate significantly arrested MCF-7 cells in the S-phase (49.40% vs 22.22% in control). This finding is consistent with impaired cell cycle progression and may be associated with the observed DNA interaction. Quantitative real-time PCR analysis of the CG compound revealed significant upregulation of BAX and CDKN1A (p21) (p ≤ 0.05) and pronounced upregulation of STK11 (LKB1) (p ≤ 0.001), suggesting activation of the AMPK signaling pathway and a metabolic stress response. Overall, the glycoconjugate ligand induces apoptosis and cell cycle arrest through oxidative and metabolic stress mediated by AMPK–STK11 signaling, highlighting its potential as a GLUT-targeted chemotherapeutic agent for breast cancer treatment.
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    Mechanistic insights into microwave-assisted ethyl acetate extraction of natural astaxanthin from Paracoccus sp. for functional products and cost estimation
    (Elsevier Ltd, 2026-08-13) Cassamo U. Mussagy; Angie V. Caicedo-Paz; Cristobál N. Alvarado-Holtheuer; M. Shaaban Sadek; Ahmad Mustafa; Diakaridia Sangaré
    This study investigates a microwave-assisted extraction (MAE) process for the recovery of astaxanthin-rich extract (ARE) from Paracoccus carotinifaciens using ethyl acetate as a recyclable green solvent, integrating mechanistic modeling and techno-economic evaluation. Experimental data combined with computational fluid dynamics (CFD) revealed that microwave-induced thermal gradients and diffusion-driven mass transfer govern pigment release and recovery. Operating conditions (350–400 W; solid–liquid ratio ∼1:30) yielded approximately 40 mg AXT eq./g within 40 min, while preventing thermal degradation. The kinetic model showed strong agreement with experimental data (R² = 0.98). The recovered ARE was successfully incorporated into a lip balm formulation, exhibiting uniform reddish–orange coloration and good stability. A preliminary techno-economic assessment indicated strong economic potential, with a return on investment (ROI) of 168% and a net present value (NPV) of $648.8 million, supporting the potential industrial scalability and economic feasibility of the proposed process. Overall, this work provides a framework combining process optimization, mechanistic understanding, and application potential for the sustainable recovery of microbial carotenoids.
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    Students’ intention to use artificial intelligence in business courses: an extended TAM approach in a developing economy
    (Frontiers Media SA, 2026-07-08) Rehab EmadEldeen; Ahmed F. Elbayuomi; Marwa Farghaly; Mohamed Samy El-Deeb; Mohamed A. K. Basuony
    Introduction: This study examines students' adoption of Artificial Intelligence (AI) in business education through an extended Technology Acceptance Model (TAM), positioning AI as an intelligent and adaptive socio-technical system rather than a conventional digital tool. Methods: Drawing on data from 521 undergraduate business students in private universities in Cairo, Egypt, the study employs structural equation modelling to investigate the psychological, contextual, and cognitive factors of AI usage. Results: Findings reveal that perceived usefulness and perceived ease of use remain central drivers of students' attitudes toward AI; however, AI-specific factors (including job relevance, self-efficacy, and perceived resource availability) significantly shape these perceptions. Notably, the results highlight the importance of contextual constraints in developing economies, where institutional support and access to technological resources play a critical role in facilitating AI adoption. Discussion: By extending TAM to the context of AI-enabled learning, this study contributes to the literature by emphasizing the dual role of AI as both a technological tool and a cognitive partner in the learning process. The findings offer implications for the design of digitally enhanced curricula, particularly in emerging markets, and provide insights into how higher education institutions can better align with the demands of an AI-driven workforce.
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    A mechanically robust and moisture-retentive hydrocolloid dressing for chronic wound management
    (Nature Research, 2026-08-12) Laila Waled; Nour. H. S. Habib; Alaa Farid; Roaa Ibrahim; Noha Elnagar; Soha M. Kandil; Gehan Safwat; Mohamed Taha
    Due to their prolonged healing times and susceptibility to infection, chronic wounds pose a significant clinical challenge. In order to improve the treatment of chronic wounds, a silver-curcumin (Ag-Cur) hydrocolloid dressing was developed in this work. integrates nanotechnology with polymer-based wound dressings by using Ag-Curcumin nanoparticles (Ag-Cur NPs) as a nano filler, which were prepared and characterized using various techniques to confirm successful formation of stable silver nanoparticles with the acceptable properties, including surface Plasmon resonance (SPR), zeta potential (ZP), dynamic light scattering (DLS), Poly dispersive index (PDI), and HR-TEM. The results demonstrated the formation of Ag-Cur nanoparticles with a hydrodynamic size of 197.3 ± 0.709 nm and a zeta potential of -27.5 ± 0.603 mV. Morphological analyses via SEM and EDX revealed a porous structure with uniform nanoparticle distribution, while mechanical testing demonstrated superior tensile strength and a swelling ratio of 428.76%, surpassing commercial dressings. The hydrocolloid dressings shown high batch-to-batch reproducibility, and the Ag–Cur nanoparticles demonstrated acceptable long-term stability. Biological evaluations showed significant antimicrobial activity against pathogens such as Staphylococcus aureus, Escherichia coli, and Candida albicans, alongside potent anti-inflammatory effects (82.43% albumin denaturation inhibition at 1000 µg/mL) and substantial antibacterial, bactericidal, and anti-biofilm activity against MRSA, highlighting its promise as a multifunctional wound dressing for infection management and reducing biofilm-related healing delay. The sustained release profile, reaching 80% after 100 h, ensures prolonged therapeutic effects. Finally, with a CC50 of 470.06 ± 23.09 µg/mL, the Ag-Cur hydrocolloid demonstrated moderate cytocompatibility with HSF-1 cells. Additionally, Ag-Cur-HCD succeeds over both Blank-HCD and Ag-HCD in suppressing LPS-induced inflammation and oxidative stress in HSF-1 cells, as seen by the IL-1β, TNF-α, and NO levels. As a result, Ag-Cur-HCD considerably modulates important inflammatory and antioxidant pathways. These results suggest that the Ag-Cur hydrocolloid shows potential for future wound dressing applications. Future studies will focus on evaluating the formulation in models of infected and chronic wounds, as well as long-term safety and comparative efficacy assessments.