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Large Language Model Enhanced Particle Swarm Optimization for Hyperparameter Tuning for Deep Learning Models
No full textDetermining the ideal architecture for deep learning models, such as the number of layers and neurons, is a difficult and resource-intensive process that frequently relies on human tuning or computationally costly optimization approaches. While Particle Swarm Optimization (PSO) and Large Language Models (LLMs) have been individually applied in optimization and deep learning, their combined use for enhancing convergence in numerical optimization tasks remains underexplored. Our work addresses this gap by integrating LLMs into PSO to reduce model evaluations and improve convergence for deep learning hyperparameter tuning. The proposed LLM-enhanced PSO method addresses the difficulties of efficiency and convergence by using LLMs (particularly ChatGPT-3.5 and Llama3) to improve PSO performance, allowing for faster achievement of target objectives. Our method speeds up search space exploration by substituting underperforming particle placements with best suggestions offered by LLMs. Comprehensive experiments across three scenarios-(1) optimizing the Rastrigin function, (2) using Long Short-Term Memory (LSTM) networks for time series regression, and (3) using Convolutional Neural Networks (CNNs) for material classification-show that the method significantly improves convergence rates and lowers computational costs. Depending on the application, computational complexity is lowered by 20% to 60% compared to traditional PSO methods. Llama3 achieved a 20% to 40% reduction in model calls for regression tasks, whereas ChatGPT-3.5 reduced model calls by 60% for both regression and classification tasks, all while preserving accuracy and error rates. This groundbreaking methodology offers a very efficient and effective solution for optimizing deep learning models, leading to substantial computational performance improvements across a wide range of applications.Scopu
Electrochemical Degradation Study of 4-Chlorophenol Using Magnesium Ferrite Catalysts Prepared by Solution Combustion
No full textElectrochemical degradation of 4-chlorophenol (4-CP) was investigated using a rotating disk electrode (RDE) over magnesium ferrite (MgFe2O4), iron-oxide and magnesium-oxide in presence of 4-CP in varying concentrations of 25, 50, and 75 mg/L. The objective of this study is to evaluate the effectiveness of these catalysts in achieving high current densities during the degradation process, and to understand their relation with the structural properties of the catalysts obtained from standard characterization techniques. Our results indicate that the MgO catalyst shows a poor current density for electrocatalytic degradation of 4-CP. However, when MgO is used in presence of iron oxide, as in MgFe2O4, a high current density for 4-CP degradation is observed, indicating the synergistic role of Mg-Fe system in improving catalytic activity. On the other hand, iron oxide alone showed the highest current density, however, most of which is expected to be associated with water splitting as opposed to 4-CP degradation. Our findings highlight the potential of magnesium ferrite based mixed oxide catalysts in environmental applications, and also provide insights into the role of Mg in modulating catalytic performance. Additionally, this work also emphasizes the role of implementing RDE technique in identifying suitable catalysts for studying 4-CP degradation in wastewater.This work was supported by the NPRP grant (NPRP13S-0109-200029) from the Qatar National Research Fund, a member of Qatar Foundation. Open Access funding provided by the Qatar National Library
Primary care physicians' perceptions of hypertension management in Qatar: A qualitative study using the theoretical domains framework
No full textAntihypertensive medications are known to reduce the incidence of hypertension complications. While the benefits of these medications are recognized, the factors influencing the prescribing practices of primary care physicians in Qatar have not been assessed. This study investigated Qatar primary care physicians' experiences, practices, and perceptions regarding hypertension management. The study further evaluated the factors that influence their prescribing behaviors and identified strategies for improving hypertension management in primary healthcare settings. A qualitative case study was conducted through one-to-one semi-structured interviews with physicians practicing at the 31 Primary Health Care Corporation (PHCC) centers in Qatar. Due to the small population size, there was no need for sample size calculation and whole population sampling was used (N=179). Physician leads at each PHCC center helped identify eligible participants. Study information were shared via email and interested candidates were contacted to arrange for interviews at their convenience. The interview guide questions were designed based on the 14 domains of the Theoretical Domains Framework (TDF) of behavior change. Interviews were conducted virtually and transcribed verbatim. Thematic analysis was undertaken using inductive and deductive approaches. Twelve themes emerged, including physicians' knowledge, skills, goals and role in hypertension management, confidence about prescribing decisions, optimism that prescriptions yield positive results, methods to ensure the appropriateness of prescriptions, emotions, and experiences when prescribing antihypertensives, perceived barriers, and facilitators when prescribing and social influences. Strategies for improving hypertension management were also suggested. In conclusion, multiple factors were identified that affect participants' antihypertensive prescribing. Further research is needed to evaluate the suggested strategies' effectiveness and to explore other improvements.Scopu
ELECTROCAOGULATION - FORWARD OSMOSIS PROCESS AS AN EFFICIENT METHOD FOR THE TREATMENT OF PRODUCED WATER FOR POSSIBLE RECYCLING AND REUSE
No full textProduced water (PW) is considered to be the largest source of industrial wastewater associated with oil and gas extraction operations leading to major impacts on the environment. Existing treatment technologies involve partially treating PW through removing the suspended solids, such as heavy metals, without removing organic components and re-injecting the water underground using water disposal injection wells. No alternate advanced treatment options on a commercial scale are available at present due to the limitations of existing PW treatment technologies, associated with their maintainability, sustainability, cost, and level of quality improvement. This thesis includes detailed literature review that discusses the latest advanced technologies for PW treatment aimed at reusing the full stream capacity of PW and eliminating the need for wastewater disposal via injection. It is concluded that researchers should focus on hybrid treatment technologies in order to remove the pollutants from PW, effectively allowing for its reuse. Moreover, produced water treatment on Lab scale using Forward osmosis system (FO) as a polisher phase is examined to determine the efficiency of pollutant removals and optimum range of parameters. The application of FO process with the use of Sodium Chloride (NaCl) as Draw solute (DS) has been investigated to treat the real produce water and to determine the efficiency of pollutant removals. The FO treatment experiment work carried out using partially treated PW after completing the initial treatment phase with Electrocoagulation (EC) process. The result showed the efficiency of PW pollutants removal by analyzing a number of parameters of pollutants including ions, metal and BEXT, Chemical Oxygen Demand (COD), Total Organic Carbon (TOC) and Oil and Greases (O&G) were tested for all conducted experiments as well. Electro-coagulation combined with an osmotic system for PW treatment appears to be an attractive system when comparing its results and performance with those of other technologies such as AOPs and bioelectrochemical and biological approaches, or even a single treatment in the tertiary phase. However, several limitations need to be addressed to de-bottleneck the existing challenges and improve the overall system to make it suitable for commercial use
Expanding access to NCD services via community retail pharmacies in LMICs: a systematic review of the literature
No full textBackground: Non-communicable diseases (NCDs) pose a significant global health challenge. In LMICs, NCDs are an incresing driver of premature deaths and have substantial economic impacts, particularly on working-age adults. The World Health Organization has identified four priority NCDs–cardiovascular diseases, diabetes, asthma/chronic obstructive pulmonary disease, and cancer–which are included in its Package of Essential Non-Communicable Disease Interventions for low-resource primary care settings. However, a shortage of healthcare professionals further compounds the problem. Pharmacists, who could play a pivotal role in NCD care, remain underutilised. Methods: We conducted a systematic literature review to identify studies on the role of community pharmacies and pharmacists in delivering NCD services in low- and middle-income settings and assessed their risk of bias. Searches were performed in PubMed, MEDLINE via Ovid, and CINAHL from 1990 to 2022, including English, French, or Spanish publications. Results: Out of 1,284 articles, 23 met inclusion criteria, predominantly focusing on diabetes (65%), followed by cardiovascular diseases (22%), cancer (9%), and asthma (4%). Most studies were conducted in Asia (52%), followed by South America (22%) and Africa (13%). Significant improvements were observed in glycaemic control and medication adherence for diabetes, and in blood pressure management and adherence for hypertension. Positive outcomes were also seen in health behaviours for breast cancer, asthma, and cardiovascular disease risk management. Interventions were cost-effective for managing diabetes and hypertension in elderly patients. However, accessibility challenges were noted in vaccination programmes, and concerns about bias were identified, particularly in observational studies. Conclusions: Expanding NCD services through community pharmacies in low and middle-income countries can significantly improve health outcomes. Pharmacists can enhance education, screening, and management for NCDs, leading to better disease control and patient satisfaction. Addressing resource constraints, legal barriers, and disease focus disparities is essential. Adequate training, financial incentives, and collaboration among stakeholders are crucial for integrating pharmacists into NCD care frameworks.This work was supported by World Bank Group. Open Access funding provided by the Qatar National Library
Online condition monitoring and fault diagnosis in wind turbines: A comprehensive review on structure, failures, health monitoring techniques, and signal processing methods
No full textWind energy systems have been flourishing on a rapid scale as a reliable renewable energy source in several countries. However, as the demand for these systems continues to grow, it becomes crucial to have a reliable and cost-effective condition monitoring system to enhance their availability. Condition monitoring plays a crucial role in achieving economic and reliable wind turbine operation. Recently, online monitoring and fault detection have been gaining greater interest in protecting these systems. Innovative and novel methods are developed to achieve real-time and remote monitoring of wind turbines. Online monitoring can offer real-time data to indicate the health condition of these systems while in service. This reduces (1) loss of production and downtime, and (2) maintenance and operational costs incurred due to system failures. This proposed work presents a comprehensive review of wind turbine online condition monitoring methods and techniques presented in the literature. Moreover, the (1) structure, (2) failures, and (3) signal processing methods of wind turbine systems were presented. Furthermore, a brief comparison was presented of (1) online monitoring techniques, and (2) signal processing methods utilized for wind turbine systems. A detailed list of published work to date has been gathered to portray a complete picture of addressed developments in this area
Psychometric properties of a questionnaire assessing the extent of integration in a problem-based learning curriculum
No full textBackground : Integrated curricula reinforce student learning and retention of relevant knowledge. At Qatar University and Arabian Gulf University medical colleges, Problem-Based Learning (PBL) is the principal teaching and learning strategy to implement integrated multidisciplinary system-based curriculum. In addition, other initiatives include integrated assessment, logical organization of teaching and learning methods, as well as combined faculty effort in curriculum planning and delivery. This multicenter study aims to develop and validate a questionnaire for measuring the extent of medical curriculum integration in PBL programs. Methods Following an extensive literature review, the content validity of a questionnaire was tested through focus group discussion with subject matter experts (n = 20), followed by pilot testing with medical students (n = 20). The content-validated questionnaire (31 items) was distributed to students in the two colleges. To examine the construct validity and construct reliability of the questionnaire, exploratory factor analysis (EFA) was conducted with 330 students followed by confirmatory factor analysis (CFA) on 579 students. Results EFA supported a four-factor structure of the questionnaire which explained 62% of the variance; however, four items were deleted because of low factor loading (< 0.5) or cross-loading on multiple factors. Further CFA also supported the four-factor structure. Another three items were removed due to high modification indices. The most parsimonious model consisted of 24 items with good fitness indices (X2= 512.23, df = 236, X2/df = 2.17, CFI = 0.97, TLI = 0.97, RMSEA = 0.04, SRMR = 0.031, and AIC = 688.22). The four factors were: Planned Curriculum (3 items), Delivered Curriculum (10 items), Assessed Curriculum (4 items) and Learned Curriculum (7 items). The factor loadings of the items ranged from 0.61 to 0.84 with strong correlations between the four latent factors (constructs). The construct reliability of the total questionnaire was 0.97 and the four factors were between 0.94 and 0.97. In addition, there were strong significant correlations between curriculum integration scores and student satisfaction with the curriculum. Conclusions The developed questionnaire exhibits good evidence of construct validity and reliability. Further studies required to test the validity of this questionnaire in other settings.Funding text 1: Open Access funding provided by the Qatar National Library.; Funding text 2: This study was funded by collaborative grant (QUCG-CMED-22/23\u2013470) from Qatar University.Scopu
Simulation and optimization of lead-free CH3NH3SnI3 perovskite solar cells using SCAPS-1D
Get PDFRecent advances in photovoltaic technology have made perovskite solar cells attractive prospects for future energy solutions. However, the presence of lead (Pb) in many perovskite materials causes environmental and health problems, limiting their practical utility. This work investigates the possibility of lead-free perovskite solar cells (PSCs) with CH3NH3SnI3 as the absorber layer. CH3NH3SnI3 is chosen for its advantageous qualities such as non-toxicity, good visible light absorption, and smaller band gap. The SCAPS-1D modeling tool was used to model these cells performance in the AM 1.5 G solar spectrum. The study looks at how varying absorber layer thicknesses, doping levels, defect densities, operating temperatures, back contact materials,series and shunt resistance affect the performance of the solar cell. The simulated device structure is FTO/TiO2/IDL/CH3NH3SnI3/Carbon, with TiO2 as the electron transport layer (ETL) and CH3NH3SnI3 as the absorber layer. At 300 K, the device exhibits an open-circuit voltage (Voc) = 0.886 V, a fill factor (FF) = 81.58 %, a short-circuit current density (Jsc) = 30.68 mA/cm2, and a power conversion efficiency (PCE) = 22.23 %.This publication was supported by QUCG grant # QUCG-YSC-23/24-217. The authors are entirely responsible for the findings presented. We are grateful to Prof. Marc Burgelman from the University of Gent in Belgium for giving access to the SCAPS software. Open access funding is provided by the Qatar National Library (QNL)
PEGylated Liposomes of Disulfiram and Paclitaxel: A Promising Chemotherapeutic Combination Against Chemoresistant Breast Cancer
Get PDFBackground: Steric stabilization of liposomes using PEGylation has been used widely in pharmaceutical research to overcome the limitations of conventional liposomes and to extend circulation time. PEGylation tended to improve the physicochemical stability and reverse the chemoresistance in multidrug-resistant (MDR) breast cancer cell lines. In this study, PEGylated formulations of disulfiram (DS) and paclitaxel (PAC) were developed using the ethanol-based proliposome technology. Methods: PEGylated liposomal formulations of disulfiram (DS) and paclitaxel (PAC) were developed using the ethanol-based proliposome approach combined with high-pressure homogenization (HPH). The liposomes were characterized for particle size, polydispersity index (PDI), zeta potential, drug loading efficiency (DLE%), and drug entrapment efficiency (DEE%). Cytotoxicity studies were performed on sensitive (MCF7, MDA-MB-231) and chemoresistant (MDA-MB-231PAC10) breast cancer cell lines using the MTT assay to assess the anti-ancer potential of the formulations. Synergistic cytotoxic effects of DS and PAC co-delivery were also evaluated. Results: There was no significant difference in drug loading (DLE%) and drug entrapment efficiency (EE%) between conventional liposomes and the developed PEGylated vesicles. DS demonstrated higher loading in liposomes than PAC, and a greater cytotoxic effect on both sensitive (MCF7 and MDA-MB-231) and chemoresistant (MDA-MB-231PAC10) human breast cancer cell lines. For both DS- and PAC-loaded liposomes, PEGylation did not compromise the cytotoxic effect on both sensitive and chemoresistant cells. Interestingly, the combination of DS- and PAC-loaded PEGylated liposomes had significantly higher cytotoxic effect and lower IC50 than that of each drug alone. Conclusions: Overall, PEGylated liposomal formulation of DS and PAC acted synergistically to reverse the multidrug resistance in breast cancer cells and could serve as a promising system for delivery of PAC and DS simultaneously in one formulation using an alcohol-based proliposome formulation.Scopu
A methodology to estimate the benefits and costs of stakeholder engagement in a transport decision-making process
Get PDFPurpose – The objective of this paper is to propose a methodology to estimate the benefits and costs of
stakeholder engagement (SE). Indeed, in the transport sector, it is consolidated that a good decision-making
process foresees the involvement of the main stakeholders, but what are the benefits and costs of the SE? How
to quantify these impacts and explicitly take them into account in a cost-benefit analysis? In this paper, an
attempt to answer these questions is provided.
Design/methodology/approach – In this paper, a methodology is proposed to estimate the benefits and
costs of SE. Moreover, the proposed methodology is applied to a case study with an attempt to identify direct
and indirect cost and benefit drivers within the context.
Findings – A range of examples of the monetary costs and benefits of SE is provided through the case study of
the high-speed rail corridor connecting Bari and Naples in Italy.
Research limitations/implications – Limits in quantifying all the aspects of engagement.
Practical implications – To be adopted by public administrations when deciding whether carrying out a
project.
Social implications – Social inclusion is a must in any decision-making process concerning big projects
affecting the community.
Originality/value –The original value of this paper is to provide a contribution to the current literature on the
quantitative representation of the impacts of SE. Indeed, a methodology to quantify and monetize the costs and
benefits of SE is proposed.Scopu