Publications by authors named "Abdulrahman Amer"

This research presents an innovative polarization-insensitive metasurface (MS) harvester designed for energy harvesting applications at 5 GHz, capable of operating efficiently over wide reception angles. The proposed MS features a novel wheel-shaped resonator array whose symmetrical structure ensures insensitivity to the polarization of incident electromagnetic (EM) waves, enabling efficient energy absorption and minimizing reflections. Unlike conventional designs, the metasurface achieves near-unity harvesting efficiency, exceeds 94% under normal incidence, and maintains superior performance across various incident angles for TE and TM polarizations.

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Article Synopsis
  • To improve the performance of porcelain insulators, applying anti-pollution flashover coatings is essential, especially given their limited hydrophobic properties.
  • The study presents a classification system for evaluating contamination levels on 22 kV porcelain insulators, using criteria developed from simulations and experiments.
  • Six criteria—including flashover voltage and insulation resistance—were tested under different conditions (uncoated, partially coated, fully coated) and various humidity levels, enabling the use of machine learning models to assess insulator condition for improved power system stability.
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This study introduces a metasurface (MS) based electrically small resonator for ambient electromagnetic (EM) energy harvesting. It is an array of novel resonators comprising double-elliptical cylinders. The harvester's input impedance is designed to match free space, allowing incident EM power to be efficiently absorbed and then maximally channelled to a single load through optimally positioned vias.

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A dual-band metasurface (MS) with a wide reception angle operating at Wi-Fi bands (2.4 GHz and 5.4 GHz) is presented for electromagnetic (EM) energy harvesting applications.

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In the present study, we further analyzed the data obtained in our previous study, where we investigated the cell-free DNA (cfDNA) of 34 progressive prostate cancer patients via targeted sequencing. Here, we studied the occurrence and prognostic impact of sequence variants according to their clinical pathological significance (CPS) or their functional impact (FI) in 23 DNA damage repair (DDR) genes with a focus on the ATM serine/threonine kinase gene (ATM). All patients had at least one DDR gene with a CPS or FI variant.

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Enterobiasis is a highly infectious parasitic disease spreading worldwide including Yemen. Therefore, this study aimed to investigate the prevalence and risk factors of enterobiasis among Yemeni children in Dhamar governorate. A total of 402 children (aged 1-12 years) participated in this cross-sectional survey carried out at Thamar University Al-Wahdah Teaching Hospital (TUWTH), between 2018 and 2019.

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Prostate cancer (PCa) is the second most common malignant cancer and is a major cause of morbidity and mortality among men worldwide. There is still an urgent need for biomarkers applicable for diagnosis, prognosis, therapy prediction, or therapy monitoring in PCa. Liquid biopsies, including cell-free DNA (cfDNA) and circulating tumor cells (CTCs), are a valuable source for studying such biomarkers and are minimally invasive.

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Prostate cancer (PCa) is the second most common cancer, causing morbidity and mortality among men world-wide. The expression of the androgen receptor (AR) and its splice variants is a crucial factor of prostate cancer biology that has not been comprehensively studied in PCa tumors. The aim of this study was to characterize the protein expression of the AR and its splice variant, AR-V7, and their subcellular distributions in PCa by immunohistochemistry and to correlate the results to the clinicopathological data and prognosis.

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Prostate cancer, the second most common cancer, is still a major cause of morbidity and mortality among men worldwide. The expression of the survival and proliferation factor progranulin (GP88) has not yet been comprehensively studied in PCa tumors. The aim of this study was to characterize GP88 protein expression in PCa by immunohistochemistry and to correlate the findings to the clinico-pathological data and prognosis.

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Many previous studies have noticed obvious alterations in different white matter tracts among patients with major depressive disorder (MDD). Growing evidence also strongly suggest a role of leptin in the pathogenesis of MDD, but with conflicting results of leptin levels. However, no previous studies have examined the relationship between leptin and white matter integrity of patients with MDD.

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Background: Artificial intelligence methods for the classification of melanoma have been studied extensively. However, few studies compare these methods under the same standards.

Objective: To seek the best artificial intelligence method for diagnosis of melanoma.

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Roflumilast is approved as an add-on therapy for chronic obstructive pulmonary disease. The inflammation in chronic obstructive pulmonary disease is mainly neutrophilic, while in asthma it is mainly eosinophilic, studies addressing role of roflumilast in eosinophilic inflammation are recommended. Also in severe asthma, the dominant inflammatory cells are neutrophils.

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Vitiligo is one of the most important skin disorders that does not cause much physical impairment, but due to its disfiguring appearance, patients have disturbances in mental health and quality of life (QoL). The dermatology life quality index (DLQI), as one of the most specific QoL instruments, is now used widely for patients with vitiligo. The main objective of this review is to collect and present detailed information about issues and disturbances related to the QoL of patients with vitiligo by reviewing the DLQI studies worldwide in the past 20 years.

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This study aims to assess the impact of childhood vitiligo on the psychological status and quality of life of their parents, and to determine how this varies according to their children's disease condition. The study included 50 families of children with vitiligo (a total of 75 participants) and 50 families of normal children (a total of 79 participants). The psychosocial impact of the disease on parents was measured using the Self-rated Health Measurement Scale (SRHMS) and the Dermatitis Family Impact Questionnaire (DFI).

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