Dr Mohammed Mahmoud Youssif

Abstract Oxide interfaces have enormous potential for future electronics with many applications, such as large spin Hall conductance, phase transitions, topological states, and superconductivity. However, previous investigations have predominantly focused on gigahertz frequencies; whilst the possibilities to fabricate devices operational at terahertz frequencies are demonstrated. A model solution is proposed employing 5d rare-earth, strontium iridate (SrIrO3) heterostructure with cobalt (Co) ultrathin layers. Femtosecond lasers are used to photoexcite the spins in Co, which super diffuse into the SrIrO3 layer to produce an ultrafast inverse spin Hall effect in sub-picosecond timescales. The devices exploit the external magnetic field and laser fluence to control the spin polarization from the Co layer and demonstrate a tailored spin Hall effect. These results thus pave paths for next-generation ultrafast oxide electronics offering possibilities for room temperature-based devices.

In the pursuit of sustainable energy solutions, the integration of renewable energy sources into power systems has received substantial attention. The enhancement of power quality metrics by utilizing sustainable solutions reducing environmental impact and carbon emissions is a current challenge in literature with ongoing research perspectives. This article proposes a unique holistic approach that integrates fuel cells, Photo Voltaic (PV) panels, Battery Energy Storage Systems (BESS), water electrolyzers, and green hydrogen storage to improve the performance of Unified Power Quality Conditioner-Distributed Generation (UPQC-DG) systems. The regulation of the DC link capacitor voltage of the UPQC-DG is also addressed in this article. In addition to, a novel power management strategy is proposed to ensure the optimal scheduling and operation of renewable energy sources. The proposed strategy addresses the intermittent nature of the renewable resources ensuring grid stability and power quality enhancement. The proposed framework aims to achieve a fully sustainable UPQC-DG holistic setup ensuring efficient utilization of renewable energy resources. It also includes a proposed enhanced wild horse optimizer technique which is applied to the formulated multi-objective function with the purpose of reducing numerous power quality indices. This guarantees a decrease in carbon emissions and lessens reliance on traditional backup sources that utilize fossil fuels. Green hydrogen storage, coupled with an electrolyzer, functions as a long-term energy buffer, capturing surplus power generated from the PV array and dispatching it to the fuel cell during periods of low generation or high demand through a power-to‑hydrogen-to-power conversion. The proposed power management strategy ensures optimal coordination between the PV panels, fuel cells, BESS, and green hydrogen storage, enabling efficient power conversion and hydrogen storage for re-electrification. Fuel cells are utilized to convert the stored hydrogen into electrical power which is utilized into regulating the common DC-link capacitor voltage, further enhancing the overall system's performance. Extensive simulations validate the effectiveness of the proposed framework in enhancing power quality. The total harmonic distortion of the supply current is consistently maintained below 1 % across various non-linear load profiles. This demonstrates the system's capability to improve power quality, ensure efficient utilization of energy resources, and provide a stable and resilient power supply. The findings suggest that the proposed fully renewable UPQC-DG system, combined with the proposed power management strategy, can significantly contribute to the transition towards a green and sustainable energy future.

Phytohormones are crucial signaling mediators that, in trace amounts, modify growth and development-related genes in plants, enhancing their resilience to stress. In the present study, temporally expressed genes of the hormone synthesis pathways for salicylic acid (SA), abscisic acid (ABA), ethylene (ET), and jasmonic acid (JA) were studied in tomato super strain B under drought stress. This cultivar is widely cultivated in Saudi Arabia, so it is a suitable model for studying this stress. Their expressions were analyzed every 2-h interval over a 48-h period. Our findings revealed that the expression pattern of ABA-related genes was more responsive to drought stress than those of ET, SA, and JA. The stomatal-related genes were sensitive to drought stress, whereas probable protein phosphatase 2C_24 and protein phosphatase 2C_53 genes were downregulated during light exposure. In contrast, the serine/threonine-protein kinase gene was upregulated during high light intensity, demonstrating how they influence stomatal reflexes to preserve water. In addition, the guard cell S-type anion channel SLAC1 gene was found to have significantly fluctuated in monitoring the ion channel responsible for drought-induced stomatal closure. The study further revealed a distinct circadian gene expression pattern of the late elongated hypocotyl (LHY) transcription factor family that was upregulated from midnight to midday and then suppressed in the afternoon and the evening, demonstrating how stress reactions and circadian cycles interact to control hormonal pathways. In conclusion, the temporal gene expression dynamics of key hormones under drought stress provide insights into developing drought-resistant tomato varieties and improving stress management strategies.

In this study, the focus was on investigating the coefficient of friction (COF), wear, and corrosion characteristics of an AA5083 aluminum matrix composite reinforced with multi-walled carbon nanotubes/graphene nanoparticles (MWCNs/GNs). The composite was fabricated using the stir-rheo-squeeze casting technique. Several key factors were explored, including the volume fraction of MWCNs/GNs, sliding speed, applied load, and wear mechanism. The research highlighted the improved tribological performance of the MWCN/GN-reinforced nanocomposite compared to the AA5083 matrix without any reinforcement. Throughout the investigation, raising the weight fraction of MWCNs/GNs guided to a gradual decline COF, wear mass loss, and corrosion rate. The optimal improvement was achieved at a volume fraction of 2 wt% of MWCNs/GNs. On the other hand, both the applied load and sliding speed were found to have an adverse effect, resulting in increased coefficient of friction, wear mass loss, and corrosion rate. The wear behavior exhibited a linear relationship across all ranges of applied loads, indicating consistent wear characteristics. To gain insights into the microstructure changes, (SEM) and (EDX) were utilized before and after the wear tests. The reinforcement of MWCNs/GNs acted as a solid lubricant, effectively reducing friction between the aluminum matrix and counterpart material. This enhancement substantially increased the wear resistance of the AA5083 matrix composite as the COF and corrosion rate reached the optimal value of 0.31 and 430 mm/year, respectively.

n/a

Nanotechnology has revolutionized the development of innovative medical and biological tools. Among these, tungsten disulfide (WS2) nanomaterials, part of the transition metal dichalcogenides (TMDCs) family, have garnered significant attention in cancer theranostics. This review synthesizes cutting-edge advances in WS₂-based systems, spotlighting their unparalleled photothermal conversion efficiency (the temperature reaches >50°C in <5 min under NIR), pH-responsive drug-loading capacity (reaches ~ 95% efficiency), and bioimaging capabilities This study pioneers the development of WS₂ nanocomposites for dual-modal cancer theranostics, achieving ~ 85% tumor reduction in vivo through synergistic photothermal therapy (PTT) and pH-responsive drug delivery. Unlike conventional transition metal dichalcogenides, WS₂ nanosheets exhibit exceptional biocompatibility (>90% cell viability) and deep-tumor penetration, enabling combinatorial photothermal-chemotherapy with 80% tumor suppression in vivo. We critically dissect innovative designs—from Au-lipid hybrids to dendrimer-functionalized nanocomposites—that overcome multidrug resistance and systemic toxicity. Further, we unveil WS₂’s catalytic enzyme activity, scavenging ROS with 90% efficiency, and its role in real-time imaging via X-ray attenuation. By addressing scalability challenges and charting a roadmap for clinical translation, this work positions WS₂ as a next-generation theranostic tool poised to redefine precision oncology.

The sluggish kinetics of the oxygen evolution reaction (OER) represents a challenge to the efficient production of hydrogen via alkaline water electrolysis (AWE). The tunable electronic properties of heterostructured materials lead to increased susceptible active sites and synergetic interactions over their constituents. Such materials offer a promising approach for enhanced OER performance. Herein, this work demonstrates a simple and controlled electrodeposition approach to fabricate a highly active and cost-effective heterostructured binary hydroxide/metallic CoNi interface over Fe3O4 electrodeposited at in-situ functionalized graphite felt (denoted as ((CoNi/Fe)Ox@GF) electrocatalyst for the OER. This approach utilizes a simple two-step electrodeposition method with electrochemical activation after each step, involving the in-situ functionalization of graphite felt (GF). The unmodified and modified GF are subjected to various characterization techniques, including XRD, Raman spectroscopy, contact angle, XPS, SEM, EDX mapping, and TEM. The fabricated (CoNi/Fe)Ox@GF electrode with optimized composition exhibits a superb electrocatalytic performance for OER in an alkaline medium (1 M KOH), which requires a marked ultra-low overpotential of 234 mV to afford a current density at 10 mA cm–2, coupled with a low Tafel slope of 34 mV dec–1. It also maintains outstanding stability at 100 mA cm–2, exceeding 24 h in 1 M KOH of continuous operation.

Background: Primary intraosseous carcinoma is a rare neoplasm of odontogenic origin. The World Health Organization defines it as a squamous cell carcinoma (SCC), usually arises inside the jaw bones and having no connection with the oral mucosa. This lesion is documented with low incidence and unfavourable prognosis. PIOC occurred mainly in older age group with potent preference to males. In this study we presented this case to add that unusual clinical presentation of this lesion to the current literature. This case showed this malignant tumour commonly known for its unfavourable behaviour and aggressiveness documented with in unusual radiographic presentation that mimics periapical cyst.Case Presentation: An old-aged heavy smoker male patient was admitted to Cairo University dental hospital with a complaint of painful swelling in his right posterior area of the mandible, started 4 months ago. Intra-oral examination revealed a swelling in the lower right posterior area in relation to the non-vital lower molars. A panoramic x-ray showed a well-defined radiolucent lesion apically to roots of lower right posterior teeth. An incisional biopsy was performed and the microscopic examination was done. The final diagnosis was confirmed to be primary intraosseous carcinoma.Conclusion: Reporting this case could add to the existing literature about adding primary intraosseous carcinoma in list of D.D of any intrabony lesion regardless its size, extension and radiographic margins. This would help clinicians to early detection and improve survival rate of such affected patients.

NMR-based Metabolomics approach assessed phytochemical profile in seed and husk of three cardamom species: Elettaria cardamomum (green), Amomum subulatum (black), and Aframomum corrorima (white). NMR Spectroscopy identified 20 metabolites belonging to sugars, amino-, organic-, fatty acids, terpenes, and phenolics. Multivariate data analyses revealed distinct metabolic profiles among the 3 species, and further in seed versus husk. A. subulatum seed showed the highest sugar and amino acid levels, while E. cardamomum seed was richer in ω-3 fatty acids. Husk, especially from A. subulatum and E. cardamomum, contained high levels of phenolic acids. Compared to other cardamom taxa, A. corrorima exhibited lower levels of most chemicals. This study highlights the potential value of cardamom husk, particularly from A. subulatum and E. cardamomum species enriched in phenolic acids and terpenes known for their antioxidant and antimicrobial properties, for use as a food preservative. The antimicrobial and antioxidant activities were assessed through in vitro assays, revealing their potential for value-added applications in food preservation and therapeutic uses.

NMR-based Metabolomics approach assessed phytochemical profile in seed and husk of three cardamom species: Elettaria cardamomum (green), Amomum subulatum (black), and Aframomum corrorima (white). NMR Spectroscopy identified 20 metabolites belonging to sugars, amino-, organic-, fatty acids, terpenes, and phenolics. Multivariate data analyses revealed distinct metabolic profiles among the 3 species, and further in seed versus husk. A. subulatum seed showed the highest sugar and amino acid levels, while E. cardamomum seed was richer in ω-3 fatty acids. Husk, especially from A. subulatum and E. cardamomum, contained high levels of phenolic acids. Compared to other cardamom taxa, A. corrorima exhibited lower levels of most chemicals. This study highlights the potential value of cardamom husk, particularly from A. subulatum and E. cardamomum species enriched in phenolic acids and terpenes known for their antioxidant and antimicrobial properties, for use as a food preservative. The antimicrobial and antioxidant activities were assessed through in vitro assays, revealing their potential for value-added applications in food preservation and therapeutic uses.

Early biomarkers of acute kidney injury (AKI) in children may help predict outcomes beyond traditional measures. We evaluated the prognostic value of urinary TIMP-2 and IGFBP7 in hospitalized children with AKI who were not critically ill.

A simple, precise, environmentally friendly, and selective high-performance thin-layer chromatography (HPTLC) method has been developed and validated for the simultaneous quantification of axitinib, pazopanib hydrochloride, crizotinib, ruxolitinib, and ibrutinib in bulk and pharmaceutical dosage forms. These five anticancer drugs are commonly utilized in the treatment of various malignancies and have demonstrated superior efficacy when used in combination therapies compared with monotherapy. This allows for dosage reduction and, consequently, a decrease in toxicity. The drugs were effectively separated on silica gel HPTLC plates (G60 F254) using a mobile phase comprising methanol–0.1% formic acid (65:35, V/V), with ultraviolet (UV) detection at 268 nm under ambient conditions. Experimental parameters were optimized, yielding linearity ranges of 5–50 µg per band for axitinib and pazopanib; 10–60 µg per band for ruxolitinib and ibrutinib; and 10–50 µg per band for crizotinib, demonstrating high sensitivity and low limits of detection: 0.052, 0.066, 0.111, 0.093, and 0.038 µg per band for axitinib, pazopanib, ruxolitinib, ibrutinib, and crizotinib, respectively. The method was successfully applied to the separation of these drugs in both bulk and dosage forms, yielding high recovery rates, which confirm the efficiency of the approach. Additionally, the greenness of the method was evaluated using the Eco-Scale Assessment (ESA), Green Analytical Procedure Index (GAPI), and Analytical Greenness Metric (AGREE) metrics, all of which confirmed its environmentally sustainable profile.

Disabled children often feel excluded and marginalized. Despite all the inclusive efforts of parents, teachers, and activists, disabilities are sometimes insurmountable hurdles that prevent children from having a normal life and from interacting with their peers. Hence, a corpus of literary works dealing with the disabled or disabilities has increased in the last two decades seeking to expose stereotyping of disability so as to offer an all-inclusive call that alerts all members of the society, especially young children, to the importance of accepting differences, thus people with disabilities. In this paper, three works for children featuring children with mobility disabilities are selected: the American play Christabel and the Amazing Pedal Power Challenge (2011), the Egyptian short story The Challenge (2015), and the Argentinian animated film Ian (2018). The three different works from different genres and cultures delve into the world of the physically disabled children around the world who often see themselves as estranged from society, exposing their emotional dilemma, pain, and struggle. These works reflect the core tenets of critical disability studies as they revisit disability, critique the social causes of disability, and offer a model for inclusion. By drawing upon critical disability studies, the paper will examine the three works focusing on the portrayal of disabled children as struggling against negative social attitudes of exclusion and stereotyping in order to finally achieve inclusion and attain a just position in their communities and societies.