Evaluating the use of paracetamol to prevent fasting headache during the first week of Ramadan: A randomized, open-label, clinical trial.

BACKGROUND: Fasting headaches frequently occur during the first few days of Ramadan, and treatment is challenging because of fasting. OBJECTIVE: This study aimed to evaluate the effect of extended-release paracetamol on preventing fasting headaches. METHODS: A randomized, open-label clinical trial investigated the efficacy of extended-release paracetamol at a daily dose of 1330 mg in preventing fasting headache. Adults aged 18 years and older were recruited through the Clinical Trial Unit at the King Saud University Medical City. The eligible participants in the study fasted 13.5 h daily during the first week of Ramadan. Participants in the treatment and control arms were followed up to investigate the occurrence, severity, and timing of headache symptoms via self-reporting using a standardized headache diary scale with a daily online link or phone call. The primary outcome was the frequency of headache episodes while fasting during the first week of Ramadan. RESULTS: A total of 238 participants were enrolled and randomized. Of these, 173 followed the protocol (80 treated, 93 control) for at least the first day and were included in the analysis. Most participants were young and healthy, with a mean age of 32.2 ± 10.2 years. More men were included in the study (102/173; 59.0%), a small proportion of participants were smokers (31/173; 17.9%), and almost all participants reported being coffee drinkers (165/173; 95.4%); nonetheless, these characteristics were evenly distributed between the two groups in the study. The overall incidence of headache episodes was 33.0% (57/173) on day 1 and decreased to 11.3% (18/159) on day 7. On average over the 7 days, no significant effect was observed for the treatment on the incidence of headache, as the findings from the generalized estimating equation model indicated (ß = -0.398, p = 0.084; odds ratio = 0.67, 95% confidence interval [CI] 0.42-1.06). Moreover, there was initially no significant difference in the incidence of headache episodes between the treatment and control groups. However, the treatment group had significantly fewer headache episodes during fasting than the control group on day 3 (4/72 [5.6%] vs. 15/91 [16.5%], p = 0.031; relative risk [RR] = 0.34, 95% CI 0.12-0.97) and day 6 (5/69 [7.2%] vs. 20/90 [22.2%], p = 0.010; RR = 0.33, 95% CI 0.13-0.82). No adverse effects were observed during the study period. CONCLUSION: No significant differences were observed in the occurrence of fasting headaches between the two groups on most days during the study period. Additional studies are required to address fasting headaches during the first week of Ramadan.

Characterization of giant endocrine cells in the fundic stomach of African catfish (Clarias gariepinus) demonstrated by histochemical, immunohistochemical and ultrastructure microscopy methods suggesting their role in immunity.

Endocrine cells in the fundic stomach of Clarias gariepinus were characterized in this work using transmission electron microscopy, immunohistochemistry, and histochemistry. Performic acid mixed with alcian blue pH2.5 and silver stain were among the histochemical stains used for endocrine cells. Endocrine cells can be found in the epithelium, lamina propria, submucosa, muscular layer, serosa, and the area between the stomach glands. Endocrine cells with one or more nuclei were found. Endocrine cells were studied using CD3, CD21, and CD68 in an immunohistochemistry analysis. The expression of the lymphocyte marker CD3 by endocrine cells is remarkable. In addition, they had a strong immunological response to CD21 and CD68, which are characteristics of phagocytic cells. Granules of varied sizes and electron densities are packed densely into the cytoplasm of the cells, as seen by transmission electron microscopy. We propose that endocrine cells play a crucial role in immune defense. The role of endocrine cells in the gut's immune system is an area that needs further investigation.

The Prevalence of Transfusion-Transmitted Infections and Nucleic Acid Testing Among Blood Donors in Makkah, Saudi Arabia.

BACKGROUND: Despite saving a vast number of lives through blood transfusions, transfusion-transmitted infections (TTIs) still threaten the lives of people needing blood transfusion. Hence, screening blood donors and reviewing the prevalence of TTIs amongst blood donors might show the impact of these infections among our people. The aim of this study was to evaluate the prevalence rates of transfusion-transmitted infections among blood donors in Makkah as foundation for providing harmless blood transfusion in Makkah, Saudi Arabia. METHODS: A retrospective study was carried out at the Central Blood Bank in Makkah city, Saudi Arabia, from January 1, 2023, to December 31, 2023. A total of 13,706 samples were collected and screened for hepatitis B surface antigen (HBsAg), hepatitis B surface antibodies (HBsAbs), hepatitis B core antibodies (HBcAbs), antibodies to hepatitis C virus (anti-HCV), antibodies to HIV 1 and 2 (HIV I/II Ab), antibodies to HTLV 1 and 2 (HTLV I/II Ab), Malarial antibodies, and antibodies to VDRL. RESULTS: A total of 13,706 blood units were received and tested. Out of the total, 52% were non-Saudi donors and 47.9% were Saudi donors; 28.4% were aged 18 - 28 years, 42.8% were aged 29 - 39 years, 24.4% were aged 40 - 50 years, and 4.4% were aged 51 - 60 years. The majority was O+ blood group (42.7%), followed by A+ (26.2%), B+ (18.7%), AB+ (4.6%), O- (3.8%), A- (2.1%), B- (1.5%), and AB- (0.4%). While 42.6% of the blood units donated were from voluntary donors, 57.4% were donated by replacement donors. Sixty-one samples (0.4%) tested positive for HBsAg, 824 samples (6%) for HBcAb, 43 samples (0.3%) for HCV antibodies, 754 samples (5.5%) for HBsAb, and 44 samples (0.3%) for HIV I/II Ag/Ab combinations. Further, 44 samples (0.3%) were positive for HTLV I/II antibodies, 83 samples (0.6%) for VDRL antibodies, and only 3 samples (nearly 0%) for malaria antibodies. Forty-three samples (0.3%) were positive for NAT-HBV, 7 samples (0.1%) were positive for NAT-HCV, and 6 samples (0.1%) were positive for NAT-HIV. The analysis revealed a statistically significant and strong correlation between HBsAgs and NAT-HBV (r = 0.819, p < 0.0001). In contrast, while there was a statistically significant association between HBsAgs and HBcAbs, the correlation was weak (r = 0.191, p < 0.0001). Additionally, there was an association between HBsAbs and HBsAgs, but the Spearman correlation indicated a very weak relationship (r = 0.042, p < 0.0001). CONCLUSIONS: Prevalence rates of transfusion-transmitted infections showed a steady decline in 2023, and these rates were much lower in Makkah than in other parts of the country or in neighboring countries. The importance of using NAT in the screening of blood donors was indicated in this study. These findings could contribute to improving the understanding of TTIs epidemiology and supporting health authorities in controlling blood-borne pathologies.

Advancing Brain Tumor Classification through Fine-Tuned Vision Transformers: A Comparative Study of Pre-Trained Models.

This paper presents a comprehensive study on the classification of brain tumor images using five pre-trained vision transformer (ViT) models, namely R50-ViT-l16, ViT-l16, ViT-l32, ViT-b16, and ViT-b32, employing a fine-tuning approach. The objective of this study is to advance the state-of-the-art in brain tumor classification by harnessing the power of these advanced models. The dataset utilized for experimentation consists of a total of 4855 images in the training set and 857 images in the testing set, encompassing four distinct tumor classes. The performance evaluation of each model is conducted through an extensive analysis encompassing precision, recall, F1-score, accuracy, and confusion matrix metrics. Among the models assessed, ViT-b32 demonstrates exceptional performance, achieving a high accuracy of 98.24% in accurately classifying brain tumor images. Notably, the obtained results outperform existing methodologies, showcasing the efficacy of the proposed approach. The contributions of this research extend beyond conventional methods, as it not only employs cutting-edge ViT models but also surpasses the performance of existing approaches for brain tumor image classification. This study not only demonstrates the potential of ViT models in medical image analysis but also provides a benchmark for future research in the field of brain tumor classification.

The prevalence of long-term rehabilitation following motor-vehicle crashes in Saudi Arabia: a multicenter study.

INTRODUCTION: In Saudi Arabia, motor-vehicle crashes (MVC) are the leading cause of disability-adjusted life years (DALYs). There is limited information locally on the magnitude and need for rehabilitation following MVC. This study examined the prevalence of MVC patients requiring long-term rehabilitation and the epidemiology of associated injuries. METHODS: A retrospective study was conducted at four hospitals of the National Guard Hospitals Affairs from January 2016 to March 2019. The study used data from an institutional trauma registry of all MVC admissions. Chi-square tests, bivariate and multivariate analyses were conducted to compare patients requiring long-term and short-term rehabilitation. RESULTS: The study included 506 patients. The study population was relatively young, with an average age was 32.8 ± 15.5 years, and the majority were males. Over two-thirds (71.3%) of patients required long-term rehabilitation. Half the patients sustained multiple fractures, and 17.0% sustained traumatic brain injuries. Overall, 53.1 and 61.8% of patients required occupational and physiotherapy, respectively. Those admitted to the intensive care unit were four times more likely to need long-term rehabilitation. CONCLUSIONS: We found a significant burden of long-term rehabilitation following MVC. Patients were relatively young, thus posing a significant burden on future healthcare utilization. Policymakers should use these findings to guide primary, secondary, and tertiary prevention to improve health outcomes.

Differences in Transporters Rather than Drug Targets Are the Principal Determinants of the Different Innate Sensitivities of Trypanosoma congolense and Trypanozoon Subgenus Trypanosomes to Diamidines and Melaminophenyl Arsenicals.

The animal trypanosomiases are infections in a wide range of (domesticated) animals with any species of African trypanosome, such as Trypanosoma brucei, T. evansi, T. congolense, T. equiperdum and T. vivax. Symptoms differ between host and infective species and stage of infection and are treated with a small set of decades-old trypanocides. A complication is that not all trypanosome species are equally sensitive to all drugs and the reasons are at best partially understood. Here, we investigate whether drug transporters, mostly identified in T. b. brucei, determine the different drug sensitivities. We report that homologues of the aminopurine transporter TbAT1 and the aquaporin TbAQP2 are absent in T. congolense, while their introduction greatly sensitises this species to diamidine (pentamidine, diminazene) and melaminophenyl (melarsomine) drugs. Accumulation of these drugs in the transgenic lines was much more rapid. T. congolense is also inherently less sensitive to suramin than T. brucei, despite accumulating it faster. Expression of a proposed suramin transporter, located in T. brucei lysosomes, in T. congolense, did not alter its suramin sensitivity. We conclude that for several of the most important classes of trypanocides the presence of specific transporters, rather than drug targets, is the determining factor of drug efficacy.

Evaluation of Hematological, Biochemical Profiles and Molecular Detection of Envelope Gene (gp-41) in Human Immunodeficiency Virus (HIV) among Newly Diagnosed Patients.

The Human Immunodeficiency Virus (HIV) is a highly morphic, retrovirus that rapidly evolves through mutation as well as recombination. Because of the immunocompromised status in HIV patients, there is often a higher chance of acquiring different secondary infections followed by liver cirrhosis, hepatitis B & C, and HIV-associated nephropathy. The current study was conducted to see the prevalence of secondary infections, hematological and biochemical markers for liver and renal associated diseases, and to detect the envelope gene (GP41) in newly diagnosed HIV patients. A total of 37 samples were collected from HIV-positive patients registered in different hospital settings under the National AIDS control program. The collected samples were processed for hepatitis B, hepatitis C, hematological analysis, and biochemical analysis. To identify the envelope gene in newly diagnosed HIV patients, polymerase chain reaction (PCR) was performed using four gene-specific primers. The HIV infections were seen more in male as compared to females. A significant decrease in complete blood count was observed in HIV patients when compared to healthy individuals. There was a significant increase in aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine observed in HIV patients. No significant difference was observed in alkaline phosphatase (ALP), total bilirubin, and albumin levels when compared to healthy control. Anemia was observed in 59.4% of HIV patients. A total of three (8.1%) patients were found to be co-infected with hepatitis B and one (2.7 %) was co-infected with hepatitis C. Out of these 37 tested samples, a total of four showed the successful amplification of the envelope gene. This study provides platform for the health care facilitators to regularly monitor the signs, symptoms and clinical biomarkers of HIV-associated infections to prevent toxicity at an early stage to improve the quality of life (QoL) and minimize the mortality rate in HIV patients. Envelope gene mutating frequently results in drug resistance, and thus future research on polymorphism analysis will reveal points of substitutions to improve drug designing.

Use of the Instantaneous Wave-free Ratio or Fractional Flow Reserve in PCI.

BACKGROUND: Coronary revascularization guided by fractional flow reserve (FFR) is associated with better patient outcomes after the procedure than revascularization guided by angiography alone. It is unknown whether the instantaneous wave-free ratio (iFR), an alternative measure that does not require the administration of adenosine, will offer benefits similar to those of FFR. METHODS: We randomly assigned 2492 patients with coronary artery disease, in a 1:1 ratio, to undergo either iFR-guided or FFR-guided coronary revascularization. The primary end point was the 1-year risk of major adverse cardiac events, which were a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization. The trial was designed to show the noninferiority of iFR to FFR, with a margin of 3.4 percentage points for the difference in risk. RESULTS: At 1 year, the primary end point had occurred in 78 of 1148 patients (6.8%) in the iFR group and in 83 of 1182 patients (7.0%) in the FFR group (difference in risk, -0.2 percentage points; 95% confidence interval [CI], -2.3 to 1.8; P<0.001 for noninferiority; hazard ratio, 0.95; 95% CI, 0.68 to 1.33; P=0.78). The risk of each component of the primary end point and of death from cardiovascular or noncardiovascular causes did not differ significantly between the groups. The number of patients who had adverse procedural symptoms and clinical signs was significantly lower in the iFR group than in the FFR group (39 patients [3.1%] vs. 385 patients [30.8%], P<0.001), and the median procedural time was significantly shorter (40.5 minutes vs. 45.0 minutes, P=0.001). CONCLUSIONS: Coronary revascularization guided by iFR was noninferior to revascularization guided by FFR with respect to the risk of major adverse cardiac events at 1 year. The rate of adverse procedural signs and symptoms was lower and the procedural time was shorter with iFR than with FFR. (Funded by Philips Volcano; DEFINE-FLAIR ClinicalTrials.gov number, NCT02053038 .).

Mycobacterium tuberculosis DNA in living donor transplanted livers and donor-related tuberculosis in recipients: A retrospective longitudinal cohort study.

OBJECTIVES: Mycobacterium tuberculosis DNA has been detected in multiple organs in people without active tuberculosis or a history of tuberculosis. Molecular testing for metabolic activity has suggested that M tuberculosis DNA represents viable bacilli. Whether transplanted organs with M tuberculosis DNA can result in tuberculosis in recipients has not been assessed. METHODS: Biopsies obtained at the time of living donor liver transplantation were tested for the presence of M tuberculosis DNA using in situ PCR. The cohort of recipients was longitudinally followed for the development of tuberculosis. RESULTS: Living donor liver transplantation was performed for 270 patients. Mean age was 33 years (median: 41 years, range: 1-80 years). Recipients were followed for a mean of 68 months (median: 72 months, range: 1-138 months) after transplantation. Mycobacterium tuberculosis DNA was detected in 25 of 155 donated livers (16%) with liver biopsies available for testing. None of the recipients of these livers received tuberculosis chemoprophylaxis and only one (4%) developed tuberculosis 15 months after transplantation. Among the entire cohort of 270 patients, post-transplant tuberculosis was diagnosed in four patients (1.48%) at an incidence rate of 2.61 cases per 1000 transplant-years. No factors associated with developing tuberculosis were identified, including positive M tuberculosis DNA in transplanted livers. CONCLUSIONS: Mycobacterium tuberculosis DNA in living donor transplanted livers did not result in tuberculosis despite post-transplant immunosuppression.

Clinical predictors of progression and clearance of low-level CMV DNAemia in solid organ transplant recipients.

BACKGROUND: Low-level CMV DNAemia is common and in the absence of treatment may either progress to higher viral loads that require therapy, or may spontaneously resolve. The clinical predictors of progression and spontaneous viral clearance are not well defined. METHODS: We performed a retrospective cohort study of organ transplant recipients who had untreated low-level CMV DNAemia (<1000 IU/mL). Outcomes were evaluated for 8 weeks after initial viral detection, and progression to CMV high viral load was defined as CMV viral load ≥1000 IU/mL. CMV DNAemia doubling time was calculated for a subset of patients with sufficient viral load timepoints. RESULTS: Of the 297 patients analyzed, 118/297 (39.7%) patients progressed to a high viral load and the remaining cleared DNAemia spontaneously (46.8%) or remained at low level (13.4%). In multivariate analysis, progression was significantly more likely in lung transplant recipients (odds ratio 3.09) and less likely in those with an episode of previously treated CMV infection (odds ratio 0.081). In a subset of 27 patients with progression, the doubling time for CMV DNAemia was a median of 6.1 days (range 2.4-21.8). CONCLUSION: We found that previous CMV infection significantly decreased the likelihood of low-level DNAemia progression suggesting that CMV immunity plays a role in progression vs spontaneous clearance.

Clinical and economic burden of infections in hospitalized solid organ transplant recipients compared with the general population in Canada - a retrospective cohort study.

Infections continue to be a major cause of post-transplant morbidity and mortality, requiring increased health services utilization. Estimates on the magnitude of this impact are relatively unknown. Using national administrative databases, we compared mortality, acute care health services utilization, and costs in solid organ transplant (SOT) recipients to nontransplant patients using a retrospective cohort of hospitalizations in Canada (excluding Manitoba/Quebec) between April-2009 and March-2014, with a diagnosis of pneumonia, urinary tract infection (UTI), or sepsis. Costs were analyzed using multivariable linear regression. We examined 816 324 admissions in total: 408 352 pneumonia; 328 066 UTI's; and 128 275 sepsis. Unadjusted mean costs were greater in SOT compared to non-SOT patients with pneumonia [(C$14 923 ± C$29 147) vs. (C$11 274 ± C$18 284)] and sepsis [(C$23 434 ± C$39 685) vs. (C$20 849 ± C$36 257)]. Mortality (7.6% vs. 12.5%; P < 0.001), long-term care transfer (5.3% vs. 16.5%; P < 0.001), and mean length of stay (11.0 ± 17.7 days vs. 13.1 ± 24.9 days; P < 0.001) were lower in SOT. More SOT patients could be discharged home (63.2% vs. 44.3%; P < 0.001), but required more specialized care (23.5% vs. 16.1%; P < 0.001). Adjusting for age and comorbidities, hospitalization costs for SOT patients were 10% (95% CI: 8-12%) lower compared to non-SOT patients. Increased absolute hospitalization costs for these infections are tempered by lower adjusted costs and favorable clinical outcomes.

Liquid Metal Antennas: Materials, Fabrication and Applications.

This work reviews design aspects of liquid metal antennas and their corresponding applications. In the age of modern wireless communication technologies, adaptability and versatility have become highly attractive features of any communication device. Compared to traditional conductors like copper, the flow property and lack of elasticity limit of conductive fluids, makes them an ideal alternative for applications demanding mechanically flexible antennas. These fluidic properties also allow innovative antenna fabrication techniques like 3D printing, injecting, or spraying the conductive fluid on rigid/flexible substrates. Such fluids can also be easily manipulated to implement reconfigurability in liquid antennas using methods like micro pumping or electrochemically controlled capillary action as compared to traditional approaches like high-frequency switching. In this work, we discuss attributes of widely used conductive fluids, their novel patterning/fabrication techniques, and their corresponding state-of-the-art applications.

Use of Viral Load as a Surrogate Marker in Clinical Studies of Cytomegalovirus in Solid Organ Transplantation: A Systematic Review and Meta-analysis.

Symptomatic cytomegalovirus (CMV) disease has been the standard endpoint for clinical trials in organ transplant recipients. Viral load may be a more relevant endpoint due to low frequency of disease. We performed a meta-analysis and systematic review of the literature. We found several lines of evidence to support the validity of viral load as an appropriate surrogate end-point, including the following: (1) viral loads in CMV disease are significantly greater than in asymptomatic viremia (odds ratio, 9.3 95% confidence interval, 4.6-19.3); (2) kinetics of viral replication are strongly associated with progression to disease; (3) pooled incidence of CMV viremia and disease is significantly lower during prophylaxis compared with the full patient follow-up period (viremia incidence: 3.2% vs 34.3%; P < .001) (disease incidence: 1.1% vs 13.0%; P < .001); (4) treatment of viremia prevented disease; and (5) viral load decline correlated with symptom resolution. Based on the analysis, we conclude that CMV load is an appropriate surrogate endpoint for CMV trials in organ transplant recipients.

What Saudi teachers know about epilepsy: A cross-sectional study of Tabuk City.

PURPOSE: This study was conducted to evaluate awareness, knowledge, and attitudes of teachers toward the disease in Tabuk City in north Saudi Arabia and identify areas in which training and education are required. METHOD: Data were collected from 349 school teachers using a structured 28-item questionnaire. Data were collected between December 2017 and May 2018 in Tabuk City. RESULTS: In general, the study shows a negative trend in knowledge and attitude toward epilepsy. The majority of the participants (84%) have read or heard about epilepsy, and more than half (67%) had witnessed a seizure. Epilepsy was considered contagious and psychological by 1.7% and 56%, respectively. Regarding attitude, 68% would not approve a son/daughter marriage to a person with epilepsy. This attitude correlates to the level of education as the percentage is higher for those who hold a Bachelor's or Master's degree, p < 0.05. Even though 84% of the participants reported knowing how to help a patient during a seizure, the majority of the participants had incorrect procedures, holding the legs and arms and believing that smelling onions is helpful to end the seizure. Moreover, almost half of the participants (46%) believed that a person with epilepsy cannot be successful in high-ranking professions. This belief was found to be more common in females than their counterparts, p < 0.05. CONCLUSION: School teachers' knowledge about epilepsy needs improvement. A focus on educational interventions about epilepsy are needed to develop a well-informed and tolerant community.

Biological markers with potential clinical value in endometrial cancer - review of the literature.

Endometrial carcinoma (EC) is the most common malignancy of the female genital tract encountered in western countries, making it the fourth most common cancer in women. The incidence of uterine cancer is on the rise throughout the developed world where diagnosis is increasingly observed among younger patients. With regard to this, attention has been focused on conducting more studies to achieve a better understanding of the molecular genetics related to endometrial carcinogenesis. Over the years, EC has been classified into two broad histopathological subtypes based on the mechanism of development, and we can therefore observe specific biomarkers related to the respective subtype. Based on this idea, more research has been carried out in the last decade, using biotechnological methods, with the aim to identify new potential tumor markers. By translating these findings into clinical use one may facilitate accurate diagnosis and prognostic prediction, and contribute to individualized treatment. Without a doubt, there is a demanding need to identify biomarkers that can be adopted in clinical practice in order to reduce the time needed to obtain diagnosis. Such markers may be of great value in improving patient outcome. However, a number of problems remain to be solved before this becomes a reality. This paper briefly reviews the current status of rising biomarkers in EC.

Fluence-to-effective dose conversion coefficients from a Saudi population based phantom for monoenergetic photon beams from 10 keV to 20 MeV.

Fluence-to-dose conversion coefficients are important quantities for radiation protection, derived from Monte Carlo simulations of the radiation particles through a stylised phantom or voxel based phantoms. The voxel phantoms have been developed for many ethnic groups for their accurate reflection of the anatomy. In this study, we used the Monte Carlo code MCNPX to calculate the photon fluence-to-effective dose conversion coefficients with a voxel phantom based on the Saudi Arabian male population. Six irradiation geometries, anterior-posterior (AP), posterior-anterior (PA), left lateral (LLAT), right lateral (RLAT), rotational (ROT) and isotropic (ISO) were simulated for monoenergetic photon beams from 10 keV to 20 MeV. We compared the coefficients with the reference values in ICRP Publication 116. The coefficients in the AP and PA geometries match the reference values to 9% and 12% on average as measured by root mean square while those in the LLAT, RLAT ROT and ISO geometries differ, mostly below, from the reference by 23, 22, 15 and 16%, respectively. The torso of the Saudi phantom is wider than the ICRP reference male phantom and likely to cause more attenuation to the lateral beam. The ICRP reference coefficients serve well for the Saudi male population as conservative estimations for the purpose of radiation protection.

Assessing Medical Student Perceptions of Open-Book Exams for Self-Directed Learning.

Introduction  The landscape of medical education is constantly evolving, with innovative assessment methods being integrated to better align with the requirements of modern healthcare education. Among these, open-book exams (OBEs) represent a significant shift from traditional closed-book exams (CBEs), promising to enhance learning outcomes and better evaluate students' understanding of medical concepts. This study aims to explore the multifaceted impact of OBEs on medical students, including their perceptions, study behaviors, stress levels, and the cultivation of critical thinking and self-directed learning skills. Methodology  This is a cross-sectional study, which utilized a mixed-methods approach, conducted at Al Baha University's College of Medicine, to explore the impact of OBEs on self-directed learning among 129 medical students over a 15-day period in October 2023. The research combined quantitative data from online questionnaires, assessing students' experiences, stress, understanding, and study strategies, with qualitative insights from in-depth interviews and open-ended survey questions. Participants were final-year medical students with prior experience in OBEs, selected to minimize bias. Data analysis was performed using Statistical Product and Service Solutions (SPSS, version 25; IBM SPSS Statistics for Windows, Armonk), focusing on descriptive and inferential statistics, while qualitative data underwent thematic analysis to identify patterns in students' perceptions of self-directed learning opportunities. The study was ethically approved, ensuring participant confidentiality and informed consent. Result  Regarding the medical student perspectives on OBEs, the study revealed that the majority of medical students strongly perceive OBEs as less stressful (77, 59.69%) and easier to prepare for (79, 61.24%) compared to traditional exams. A significant proportion also believe OBEs accurately assess their comprehension (106, 82.17%) and prefer them as a mode of assessment (106, 82.17%). Furthermore, most students (87, 67.44%) reported performing better on OBEs compared to CBEs. Regarding the assessment of self-directed learning using the OBE method, students predominantly utilized highlighting important points (70, 54.26%) as a preparation method for OBEs. A large majority (85, 65.89%) considered OBEs as a fair assessment of self-directed learning and believed that they encourage self-directed learning (114, 88.37%). Conclusion  OBEs represent a promising direction for medical education, offering a way to better prepare students for the complexities of real-world medical practice. Future strategies should include not only the refinement of OBE methodologies but also the integration of practice opportunities that enable students to hone their skills in applying knowledge effectively.

Boosting cuckoo optimization algorithm via Gaussian mixture model for optimal power flow problem in a hybrid power system with solar and wind renewable energies.

This paper presents a novel approach, the Gaussian Mixture Method-enhanced Cuckoo Optimization Algorithm (GMMCOA), designed to optimize power flow decision parameters, with a specific focus on minimizing fuel cost, emissions, network loss, and voltage deviation. GMMCOA integrates the strengths of COA and GMM while mitigating their individual limitations. While COA offers robust search capabilities, it suffers from initial parameter dependency and the risk of getting trapped in local optima. Conversely, GMM delivers high-speed performance but requires guidance to identify the best solution. By combining these methods, GMMCOA achieves an intelligent approach characterized by reduced parameter dependence and enhanced convergence speed. The effectiveness of GMMCOA is demonstrated through extensive testing on both the IEEE 30-bus and the large-scale 118-bus test systems. Notably, for the 118-bus test system, GMMCOA achieved a minimum cost of $129,534.7529 per hour and $103,382.9225 per hour in cases with and without the consideration of renewable energies, respectively, surpassing outcomes produced by alternative algorithms. Furthermore, the proposed method is benchmarked against the CEC 2017 test functions. Comparative analysis with state-of-the-art algorithms, under consistent conditions, highlights the superior performance of GMMCOA across various optimization functions. Remarkably, GMMCOA consistently outperforms its competitors, as evidenced by simulation results and Friedman examination outcomes. With its remarkable performance across diverse functions, GMMCOA emerges as the preferred choice for solving optimization problems, emphasizing its potential for real-world applications.