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UNRAVELING THE INTERMOLECULAR ELECTRON TRANSFER OF POROUS CARBON NANOFIBERS DERIVED FROM COTTON WASTES VIA INTERFACIAL HETEROATOMS DEFECTS FOR GREEN HYDROGEN PRODUCTION
No full textRational design of efficient electrocatalysts for hydrogen evolution reaction (HER) has sparked the global attention to decrease the cost of green hydrogen production, however it remains challenged. In this thesis, we unravel the simple, green, and one-pot method for the scalable design of ultra-long (1-3 mm) carbon fiber (p-CFs) from cotton fiber biomass wastes atomically functionalized with heteroatoms (HAs) at the atomic level (HAs/p-CFs) (HAs= O, B, P, N, and F) by immersion and carbonization method at relatively low temperature. The interaction between electronegative HAs and CFs led to an optimal intermolecular charge transfer process giving rise to efficient electrocatalyst with rich active sites; however O/p-CFs was the optimum. The HER activity followed the trend of O/p-CFs >B/h-CNF > P/p-CFs >N/p-CFs >F/h-CNF>p-CFs. The HER current density reached 325 mA/cm2 on O/p-CFs with a low overpotential at 10 mAcm2 (ƞ10) of -0.3 V, and H2 production rate of 109 mol· gmetal-1·h-1. The HER activity of O/p-CFs was close to Pt/C, and it was among highest reported carbon-based electrocatalysts besides ease of preparation method. This is due to unique structural merits and atomic distribution of O-atom that generate rich interfacial structural defects within CFs framework, and endowing the intermolecular electron transfer at O/p-CFs interfaces results in efficient HER. These findings may pave the way for engineering of biomass wastes with other HAs for green HER
Surgical repair techniques in hypospadias with unfavorable urethral plate: A systematic review and network meta-analysis
No full textIntroductionHypospadias is one of the most common urogenital malformations in male newborns. Numerous techniques exist for repairing hypospadias, including urethral advancement, tubularized incised plate (TIP), flaps, and graft-tubularized incised plate (GTIP). However, it remains unclear which approach is optimal in cases with an unfavourable urethral plate. ObjectiveThis systematic review and network meta-analysis compares efficacy, complication rates, and patient outcomes of the various surgical procedures used to repair hypospadias with an unfavorable urethral plate. Study designPreferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) guidelines were used to conduct a search of PubMed, Cochrane Library, Embase, and Science Direct databases up to May 4, 2024. Studies were rigorously screened and evaluated using Cochrane Risk of Bias 2.0. A random-effects meta-analysis was conducted using R-Studio to combine effect estimates. Included were peer-reviewed publications of randomized controlled trials, prospective cohort studies, and retrospective studies involving male patients diagnosed with hypospadias and “unfavorable urethral plate”. Results and discussionA total of 20 studies representing n = 1483 patients were included, screened, and displayed low risk of bias. Four studies were included in the network meta-analysis. Narrow meatus were found to be more prevalent in TIP urethroplasty, while glans dehiscence was less common with flaps. Additionally, TIPs and GTIP displayed lower incidence of diverticulum compared to flaps. The network meta-analysis indicated no significant differences between the three procedures in terms of fistula complication (Flap [OR 0.41; 95 % CI 0.11–1.50] and GTIP [OR 0.52; 95 % CI 0.17–1.57]). GTIP procedures were associated with fewer overall complications (OR 0.37; 95 % CI [0.19–0.75]). ConclusionFlap and GTIP techniques may display lower complication rates than TIP in cases of unfavorable urethral plate, with modest superiority of the GTIP approach. Flap and GTIP techniques may therefore be optimal for repairing hypospadias in cases of unfavorable urethral plate, although high-quality comparative studies are needed to confirm this finding
AACSB Reaccreditation Awarded to Accounting Program
No full textThe Accounting program at the College of Business and Economics, Qatar University, has successfully maintained its specialized AACSB accreditation
Methodological Landmarks and Aspects of Renewal in Sheikh Yūsuf al-Qaraḍāwī's Stance on Western Civilization and Islamic Revival
No full textأهداف البحث: الشيخ القرضاوي رحمه الله شغلته قضيتا الموقف من الحضارة الغربية، ومنهجية إعادة البعث الحضاري عند المسلمين، وهذه الدراسة جاءت بهدف بيان المعالم المنهجية الكبرى، ومواطن التجديد الحضاري المرتبطة بموضوع العلاقة بين الإسلام والغرب في فكر الشيخ رحمه الله.
منهج الدراسة: انتهجت هذه الدراسة منهجا تحليليًا وصفيًا.
أصالة البحث: تظهر من خلال تمام الانسجام بين فكر الشيخ القرضاوي ومشروعه الحضاري، وبين متطلبات المرحلة القادمة للعالم الإسلامي، فيما يرتبط بالحضارة الغربية والنهضة الإسلامية المستقبلية المأمولة.
نتائج الدراسة: خلصت الدراسة إلى أن موقف الشيخ من الحضارة الغربية ليس مرادا لذاته، بل هو وليد اهتمامه بقضية البعث الحضاري الإسلامي الجديد، وأنه يتميز بالإنصاف والواقعية والإيجابية، من خلال الحوار والانفتاح المنضبط والمعاصرة والاقتباس والانتقاء المستبصر، وأن مشروع الشيخ الإصلاحي هو نسخة مطورة ناضجة من تيار الإصلاح يعتمد التجديد والاجتهاد والواقعية والمعاصرة، وينبذ الماضوية والجمود والتقليد.Objectives: Sheikh al-Qaraḍāwī profoundly engaged with two key issues: the approach to Western civilisation and the pursuit of a civilisational revival among Muslims. This study seeks to identify the methodological principles and elements of renewal within al-Qaraḍāwī’s perspective on these topics.
Methodology: The study follows a descriptive and analytical approach.
Results: The study concludes that Sheikh al-Qaraḍāwī’s stance on Western civilisation is not an end in itself but reflects his commitment to the new Islamic civilisational revival. His approach is marked by fairness, realism, and positivity, embracing dialogue, disciplined openness, modern relevance, thoughtful borrowing, and discerning selection. His reformist vision represents a mature, evolved approach to reform, one that values innovation, diligent inquiry, realism, and contemporaneity while rejecting traditionalism, stagnation, and blind imitation.
Originality: This study's uniqueness lies in the alignment between Sheikh al-Qaraḍāwī’s thought and civilisational vision and the evolving needs of the Islamic world in relation to Western civilisation and the anticipated future Islamic renaissance
Extreme outage prediction in power systems using a new deep generative Informer model
No full textExtreme weather events have made growing concerns over electric power grid infrastructure as well as the residents living in disaster areas. Moreover, the potential damages due to the extreme events can make serious challenges for supply reliability and security, leading to widespread power outages in power systems. This paper proposes a deep learning-based framework for power data rebalancing and outage prediction in power systems to cope with the extreme events. To this end, we propose an Adaptive Wasserstein Conditional Generative Adversarial Network for data generation. Also, we propose a new Wasserstein Bidirectional Generative Adversarial Network with the Informer model, embedded in both the Generator and Discriminator Networks, plus an Encoder Network for the outage prediction in power systems. Two-step classification approach has been used in the proposed outage prediction model: classifying the power grid components into impacted and non-impacted categories and classifying the impacted category into in-service and out-of-service categories. In addition, a new classification-specific loss function is proposed for the minimax objective function of the Vanilla Generative Adversarial Network to improve the prediction performance in the latent space. Evaluation results of the proposed model and 15 comparative models in three groups using six evaluation metrics on a real-world test case demonstrate the superiority of the proposed model compared to all comparative models. These results confirm that the proposed outage prediction model can be effectively employed for accurately predicting extreme outages in power systems.This research was made possible by the 1st Cycle of ARG Grant No. ARG01-0504-230073, from the Qatar Research, Development and Innovation (QRDI) Council, Qatar. The findings herein reflect the work, and are solely the responsibility, of the authors. The authors also gratefully acknowledge support from Qatar University. Open Access funding provided by the Qatar National Library
Complex Coacervation of Plant-Based Proteins and Polysaccharides: Sustainable Encapsulation Techniques for Bioactive Compounds
No full textComplex coacervation is a phase separation phenomenon between two oppositely charged colloids, such as proteins and polysaccharides, when mixed in a solution. The attractive forces between the oppositely charged particles lead to the formation of a coacervate phase, which is a liquid, dense, and polymer-rich phase. Animal-based proteins and polysaccharides are commonly used to prepare high-quality bioactive compounds and are widely used to produce complex coacervations with desirable physicochemical properties. During complex coacervation, utilizing animal-based proteins, such as casein, offers several advantages. However, challenges and concerns are associated with their production, including high costs, environmental impact, the spread of animal diseases, and the emergence of drug-resistant pathogens. As an alternative to animal-based proteins, plant-based proteins are gaining traction in complex coacervation, addressing several challenges associated with animal-based protein production. Plant-based proteins provide a range of benefits that align with environmental sustainability, cost-effectiveness, and reduced concerns about animal diseases. Some key advantages of employing plant-based proteins in complex coacervation include sustainability, biocompatibility, reduced ecological impact, disease resistance, diversity of sources, consumer demand, and allergen considerations. Various physical, chemical, and biological processes are employed to enhance the characteristics of plant-based protein-polysaccharide coacervates. This comprehensive review elucidates recent advancements in the microencapsulation of bioactive compounds through complex coacervation utilizing plant-based protein-polysaccharide systems. This review serves as a valuable resource for summarizing the current state of research, identifying limitations and gaps in knowledge, and discussing challenges within the field
An Insight Into Unveiling Nano Luminescence for Industrial Dye Detection
No full textDye, a major contaminant from the textile, paper, and pulp industries, is a serious environmental and human health hazard. Because of their low cost, environmental friendliness, and sustainability, semiconductor nanoparticles are among the most effective photocatalysts for detecting dyes in wastewater. Quantum dots (QDs), particularly Carbon quantum dots (CQDs), have received a lot of attention due to their unique optical and electrical properties, making them excellent for applications such as sensing and detection. This paper describes a unique microwave-assisted method for synthesising CQDs in ambient reaction conditions, providing a fast, scalable, and passivation-free alternative to traditional methods. The CQDs were characterised using SEM, XRD, FTIR, UV–Vis spectrophotometry, and photoluminescence, which confirmed their uniform size distribution and outstanding optical characteristics. The CQDs had detection limits of 0.413 ppm for cresol red and 0.847 ppm for cresol purple, indicating great sensitivity and selectivity over a wide pH range. These findings propose a new, sustainable, and cost-effective alternative for tackling water pollution and its detrimental effects on aquatic ecosystems, hence increasing the use of Carbon QDs in environmental restoration.Open Access funding provided by the Qatar National Library. Qatar National Research Fund supported this work under grant no. MME03-1226–210042. The statements made herein are solely the responsibility of the authors
AI-POWERED DIGITAL BEAMFORMING FOR 6G COMMUNICATIONS: TOWARDS GENERALIZED ADAPTIVE BEAM SELECTION
No full textThe evolution of wireless communication networks toward sixth-generation (6G) systems presents significant challenges in achieving efficient and adaptive beamforming, particularly in millimeter-wave (mmWave) and sub-terahertz (THz) frequency bands. Traditional beamforming techniques rely on exhaustive search-based methods and predefined codebooks, which suffer from high computational complexity, latency, and limited adaptability in dynamic environments. Machine learning (ML) offers a promising alternative by leveraging multimodal data-driven approaches to improve beam selection accuracy, generalization, and real-time adaptability. This thesis explores the integration of ML-based techniques for beamforming, proposing two novel approaches: a deep learning-based beamforming model and a federated transfer learning (FTL) framework. The first approach employs convolutional neural networks (CNNs) and gated recurrent units (GRUs) to process multimodal sensory data, including radar, LiDAR, and GPS signals, for enhanced beam selection in dynamic environments. The second approach introduces a Maturing Federated Transfer Learning (MFTL) framework, which enables privacy-preserving and distributed learning while addressing data heterogeneity across network nodes. The proposed framework significantly improves beam selection performance without requiring centralized data collection by incorporating edge-based training and adaptive aggregation techniques. Extensive experiments were conducted using real-world and simulated datasets, including DeepSense6G and 5G MIMO, to evaluate the proposed models against stateof- the-art (SOTA) methods. Performance metrics such as Top-1, Top-3, and Top-5 accuracy, along with Distance-Based Accuracy (DBA) scores, validate the effectiveness of the proposed ML-based beamforming strategies. Results demonstrate substantial improvements in beam selection accuracy, computational efficiency, and adaptability to dynamic and heterogeneous wireless environments. The findings of this research contribute to the advancement of ML-driven beamforming methodologies, paving the way for more intelligent, scalable, and energyefficient beam selection mechanisms in 6G networks. Future work will explore reinforcement learning-based beam optimization, as the dynamic nature of the problem makes it well-suited for RL. Additionally, the federated learning framework requires further enhancements to effectively address the system's data heterogeneity. A metalearning approach is also a promising option to improve model adaptability and achieve better generalization across diverse scenarios
TARGETING ENDOTHELIAL-TO-MESENCHYMAL TRANSITION IN DOXORUBICIN-INDUCED CARDIOVASCULAR TOXICITY: THE ROLE OF CYP EPOXYGENASES AND SOLUBLE EPOXIDE HYDROLASE/CYCLOOXYGENASE-2 INHIBITION
No full textBackground: Doxorubicin (DOX) is an anthracycline widely used against many neoplastic diseases. However, the clinical use of DOX is limited due to its dose-dependent cardiovascular toxicity. Recent studies suggest that Endothelial-to-Mesenchymal transition (EndMT) and endothelial toxicity may contribute to the pathogenesis of DOX-induced cardiovascular toxicity. Given that Arachidonic Acid (AA) and associated Cytochrome P450 (CYP) epoxygenase, soluble epoxide hydrolase (sEH) and cyclooxygenase-2 (COX-2) have been involved in vascular endothelial and cardiovascular function, we aimed to examine the effect of suppressing CYP epoxygenases using MSPPOH on DOX-induced EndMT and cardiotoxicity. We also aimed to investigate the effect of PTUPB, a dual sEH/COX-2 inhibitor, on DOX-induced EndMT, vascular and cardiac toxicity. Methods: Human endothelial cells were treated with DOX, with/without CYP epoxygenase inhibitor, MSPPOH. We also investigated the effect of MSPPOH on the cardiovascular system in zebrafish. Additionally, we tested the potential beneficial impact of PTUPB on DOX-induced cardiovascular toxicity in zebrafish and DOX-induced EndMT in human endothelial cells. Results: Inhibiting CYP epoxygenase using MSPPOH exacerbated DOX-induced EndMT, inflammation, oxidative stress and apoptosis in our endothelial cells. Furthermore, MSPPOH increased cardiac edema, lowered blood flow velocity, and worsened the expression of EndMT and cardiac injury markers in a zebrafish model of DOX-induced cardiovascular toxicity. Conversely, inhibition of sEH and COX-2 using PTUPB reduces DOX-induced EndMT and vascular toxicity. Also, PTUPB improves cardiac function and morphology in zebrafish incubated with DOX. Importantly, our results demonstrate that PTUPB downregulates inflammation and oxidative stress markers to contribute to the improvement observed in DOX-induced cardiovascular toxicity. Conclusion: Our data indicates that a selective CYP epoxygenase inhibitor, MSPPOH, worsens DOX-induced EndMT vascular and cardiac toxicity. On the other hand, suppressing sEH/COX-2 using PTUPB reduces DOX-induced EndMT, vascular, and cardiac toxicity
GENETIC ANALYSIS OF CHARCOT-MARIE-TOOTH DISEASE IN THE POPULATION OF QATAR.
No full textBackground: Charcot-Marie-Tooth (CMT) disease represents a group of inherited neurological disorders characterized by chronic motor and sensory neuropathy that causes several symptoms such as, progressive muscle weakness, foot deformities, and peripheral neuropathy. CMT has a worldwide prevalence of approximately 1 in 2,500 individuals. Aim: This study aims to investigate the genetic basis of CMT disease in the population of Qatar, evaluate the diagnostic yield of various genetic testing methods utilized in Qatar, and explore the genotype-phenotype correlations among patients diagnosed with CMT. Methodology: A retrospective chart review was conducted on 25 adult patients diagnosed with CMT who were seen at the Medical Genetics Department at Hamad Medical Corporation (HMC), Qatar, between January 2015 and May 2024. All included patients underwent genetic testing, including chromosomal microarray analysis (CMA), multi-gene panel testing, or whole exome sequencing (WES). Results: The overall diagnostic yield of genetic testing for CMT in this cohort was 68%. Among the individual testing methods, WES had the highest diagnostic yield at 60%, followed by CMA at 42%, and CMT panel testing at 33%. A total of 17 cases were classified as genetically confirmed CMT. A total of 17 cases were classified as positive cases with a genetic diagnosis of CMT. Three cases were found to have variants of uncertain significance (VUSs). The re-evaluation of these VUSs resulted in the consideration of one variant as being pathogenic and contributing to the phenotype seen in patient, therefore, the case was re-categorized as positive. We also identified the two most common genes associated with CMT in Qatar as being the SORD gene, followed by the PMP22 gene. The most common clinical feature among genetically confirmed CMT patients was progressive lower limb weakness, seen in 16 out of 17 individuals, followed by neuropathy in 11 patients and foot drop in 7. Less frequent features included pes cavus, hammer toes, hearing loss, tremors, balance issues, burning sensations, and hand clawing, each observed in only a few patients Conclusion: This study represents the first genetic analysis of CMT in Qatar and highlights SORD as a potential first-tier target for genetic testing in Qatari families. Our findings also support the use of WES as a follow-up test after negative initial genetic testing, given its high diagnostic yield. This approach may improve diagnostic efficiency while minimizing unnecessary costs and use of resources