Publications by authors named "Amal Abdelkarim"

Archaeological coins are considered essential sources of historical documentation. Over time, they are subjected to corrosion processes that gradually alter their appearance, shape, and composition. This study aims to evaluate the effects of the patina and/or protective coating on the corrosion process.

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This study aims to prepare Ag-CuO nanoparticles and assess their efficiency in protecting the copper substrate. The prepared Ag-CuO nanoparticle was characterized using, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope/energy-dispersive X-ray (SEM/EDX), and transmission electron microscope (TEM). The anticorrosion performance of the epoxy coatings containing various weight percentages of Ag-CuO nanoparticles was evaluated in 3.

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Polyaniline/nanocarbon (PANI/NC) nanocomposites have been prepared by in situ polymerization of aniline monomer in the presence of a stable colloidal solution of nanocarbon NC using ammonium persulfate as an initiator and silver ions (Ag) as oxidizing agents to produce PANI/NC and PANI/NC/AgO nanocomposites, respectively. The morphological studies of the formed nanocomposites have been elucidated via transmission and scanning electron microscopes (TEM and SEM). Further characterization of the prepared nanocomposites has been done via infrared spectroscopy (IR), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), particle size distribution analysis (PSD), fluorescence microscope (FM), UV-VIS spectroscopy, and finally surface analysis.

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In the current work, rice straw nanofibers (RSNF) with the width of elementary fibrils (~ 4-5 nm) were isolated from rice straw. The isolated nanofibers were used with zinc oxide nanoparticles (ZnONPs) to prepare flexible nanopaper films. Tensile strength and electrical properties of the prepared RSNF/ZnONPs nanopaper were investigated.

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Background: Chronic sleep fragmentation (SF) without sleep curtailment induces increased adiposity. However, it remains unclear whether mobilization, proliferation, and differentiation of adipocyte progenitors (APs) occurs in visceral white adipose tissue (VWAT), and whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2) activity plays a role.

Methods: Changes in VWAT depot cell size and AP proliferation were assessed in wild-type and Nox2 null male mice exposed to SF and control sleep (SC).

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Obstructive sleep apnea (OSA) is a prevalent condition and strongly associated with metabolic disorders. Sleep fragmentation (SF) is a major consequence of OSA, but its contribution to OSA-related morbidities is not known. We hypothesized that SF causes specific perturbations in transcriptional networks of visceral fat cells, leading to systemic metabolic disturbances.

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Obstructive sleep apnea (OSA) is a prevalent disorder characterized by intermittent hypoxia (IH) during sleep. OSA is strongly associated with obesity and dysregulation of metabolism-yet the molecular pathways linking the effects of IH on adipocyte biology remain unknown. We hypothesized that exposure to IH would activate distinct, time-dependent transcriptional programs in visceral adipose tissue of mice.

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