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Certain phenomena with uncertain properties that take the shape of intricate mathematical modeling are known to have fuzzy system integro-differential equations (FSIDEs). The methods used to roughly solve FSIDEs seek to provide open-form solutions that are regarded as solutions for polynomial series. However, for many FSIDEs, the polynomial series solutions are not easily derived, especially in nonlinear forms. Meanwhile, some existing approximate techniques cannot guarantee convergence of the series solution. Nevertheless, to solve second-kind fuzzy Fredholm integro-differential equations (FFSIDEs), there exist perturbation techniques based on the standard Homotopy Analysis Method (HAM) that have the ability to control and rate solution convergence. Therefore, this study focused on modifying new approximate techniques, fuzzy Fredholm HAM (HAMFF), for solving second-kind FFSIDEs subject to initial and boundary value problems. In the theoretical framework modification, the establishment of the series solution convergence was done based on combining some fuzzy sets theory concepts and convergence-control parameters from standard HAM. The HAMFF was not only able to solve linear systems but also difficult nonlinear systems with proper accuracy. The demonstration of the modified technique's performance was shown in comparison to other methods, where HAMFF was individually superior in terms of accuracy for solving linear and nonlinear test problems of FFSIDEs. more...

Background Judging the stability/activity of vitiligo is of therapeutic and prognostic significance. Clinical and biochemical activity indicators are available, but none is currently universally accepted. Objective To compare the accuracy of patient-derived vitiligo disease activity score (VIDA) and dermoscopy, versus sequential planimetry in determining vitiligo stability/activity. Patients and methods A total of 120 nonsegmental otherwise healthy vitiligo patients were included, who reported disease stability for the last 6 months. Global assessment and photography were followed by choosing a stable non-repigmenting lesion for longitudinal evaluation of planimetric changes, and dermoscopy. Patients received the standard protocol of narrow band ultraviolet B for 3 months, and patient recall for global and lesional progression was recorded. Accuracy of patient-derived VIDA and dermoscopic signs, versus planimetric changes as the reference were compared for judging vitiligo stability/activity. Results Patient-derived VIDA showed 58.33% accuracy in determining disease stability while Dermoscopy showed 97.50% overall accuracy. The absence of a pigment network and the absence of signs of activity (collective absence of ill-defined border, satellite lesions, and microkoebnerization) showed 100% accuracy in establishing disease stability. On the other hand, the presence of any microkoebnerization, starburst sign, or satellite/tapioca sago sign was 100% indicative of activity. Border definition gave a 91.67% overall accuracy for judging stability, while Perifollicular pigmentation showed an accuracy of 49.17%. Conclusion Patient-derived VIDA is generally unreliable, whereas longitudinal follow-up for planimetric changes, and dermoscopic assessment are of better reliability. The absence of pigment network, and collective absence of ill-defined border, microkoebnerization, and satellite lesions are 100% accurate in predicting stable vitiligo. more...

Abstract This article reports an Ultra wideband nano scale metamaterial absorber with ultrathin and flexible feature for visible spectrum applications. The absorber investigated for dispersion and Fano resonance characteristics to achieve metamaterial properties as well as independent of asymmetry of structure. Maximum visible spectrum wave interaction with the cascaded split nano square meta atom also ensured to achieve the absorption at highest percentage in numerical evaluation. The Finite Difference Time Domain (FDTD) method incorporated with CST microwave studio computational tool used for the entire analysis. Numerical analysis revealed that, on average 86.66% absorption achieved for 560 THz bandwidth peak absorption for the unit cell was 99.88% and the array shows 99.79%. Dispersion gap optimized based on mode 4 to incorporate all photons for phase and group velocity inside the nano metamaterial absorber. Furthermore, the Fano resonance wave to identify the high-quality factor at visible spectrum on nanostructure meta atom and direct-indirect visible wave trapped in the structure. The dispersion gap optimization and Fano resonance make the proposed cascaded split nano square meta atom a significant candidate for visible spectrum applications like solar energy harvesting, biochemical sensing, optical range application etc. more...

Application: Micro- and nano-cavitation technology is a new way to solve some environmental issues, such as climate change, manufacturing cost and energy reduction, therapeutic and diagnostic procedure optimization, and other problems. Even though the manufacture and use of microcavitation is a relatively new topic, there are a lot of publications and research about their properties and their potential applications in numerous sectors. Novel classes of heat transfer fluids based on nanotechnology, known as nanofluids, are created by dispersing and steadily suspending nanoparticles, typically between 1 and 50 nm long in conventional heat transfer fluids. Over the last ten years, incredible discoveries have been made by trailblazing scientists and engineers that a minimal amount of guest nanoparticles can dramatically enhance the thermal properties of the host fluids. Novelty: Motivated by these advances, this work is devoted to studying the microcavitation bubbles’ evolution process in ternary-hybrid nanofluids (namely, tri-hybrid nanofluids) near an elastic wall by using the analytical investigation. The proposed model of microcavitation dynamics is formulated based on the Keller-Miksis model, which describes cavitation bubbles near the elastic rigid body with shell thickness for two nanofluids. Methodology: The model of modified Keller-Miksis is solved analytically via the modified Plesset-Zwick method in mono, hybrid, and ternary-hybrid nanofluids with consideration of the variety of surface tension. Different types of thermophysical configurations of nano, hybrid, and ternary-hybrid nanofluids are described and developed to study the cavitation behaviour for various values of volume concentration of nanoparticles. Findings: The main goal of this analysis is a theoretical explanation and mathematical modeling of microcavitation dynamics in ternary-hybrid nanofluids with a variety of surface tension. The microcavitation process in multi-walled carbon nanotube (MWCNT)-Au-Ag/blood for ternary-hybrid nanofluid is lower than that in the cases of MWCNT-Ag/blood for hybrid nanofluid and MWCNT/blood for nanofluid and pure blood fluids. The effect of volume concentration of the used nanoparticles reduces the behaviour of cavitation dynamics near the elastic rigid body with shell thickness in ternary-hybrid nanofluids. The obtained results are schematically and graphically presented by using Mathematica symbolic software to investigate the impact of the thermophysical properties of the ternary-hybrid nanoparticles on the radius of the vapor bubble and compare with the previous related works. more...

The digitalization of educational systems and the corresponding impact on the learners’ improvement require modern pedagogical approaches to increase motivation among learners in distance learning. According to the literature, authentic e-learning and real-world themes create a dynamic learning setting and enhance learners’ engagement; however, the impact of adopting authentic learning has not been investigated for deaf learners in a sign language e-learning setting. Therefore, this study aims to examine the effect of adopting authentic learning for the design of e-learning for deaf learners. The study employed a mixed-methods approach by conducting a one-group pre-test–post-test with 11 deaf learners and measuring design principles of authentic learning via semi-structured interviews. The statistical portion analyzed the T-test and Cohen’s d-effect size, and the result showed that e-learning through authentic themes was significantly effective. The interview results revealed a positive attitude toward using e-learning based on an authentic learning approach, which increased deaf learners’ motivation. It was found that e-learning based on an authentic sign language e-learning setting and technology enhances deaf learners’ satisfaction and motivation with their first e-learning experience. more...

Resting state networks (RSNs) of the brain are characterized as correlated spontaneous time-varying fluctuations in the absence of goal-directed tasks. These networks can be local or large-scale spanning the brain. The study of the spatiotemporal properties of such networks has helped understand the brain’s fundamental functional organization under healthy and diseased states. As we age, these spatiotemporal properties change. Moreover, RSNs exhibit neural plasticity to compensate for the loss of cognitive functions. This narrative review aims to summarize current knowledge from functional magnetic resonance imaging (fMRI) studies on age-related alterations in RSNs. Underlying mechanisms influencing such changes are discussed. Methodological challenges and future directions are also addressed. By providing an overview of the current state of knowledge in this field, this review aims to guide future research endeavors aimed at promoting healthy brain aging and developing effective interventions for age-related cognitive impairment and neurodegenerative diseases. more...

To govern the complex rheological dynamics of fluid simulations, numerous mathematical approaches are being developed. The examination of such mathematical frameworks employs theoretical, iterative, empirical, and analytical methodologies. This work analyzes and evaluates the Laplace transforms to estimate the time-dependent mixed convective flow of hybrid nanofluid in a porous material. A hybrid nanofluid is produced through dispersing molybdenum disulfide (MoS2) and silicone dioxide (SiO2) nanoparticles in carboxymethyl cellulose (CMC −water). The objective of this study is to examine the heat transfer properties of a hybrid nanofluid (MoS2−SiO2)/(CMC −water) flowing over a vertical sheet while being subjected to a thermal radiation and heat source and sink. The Laplace transform approach has been used in closed form to solve the resulting partial differential equations governing the flow. This study examines how hybrid nanofluids influence time-dependent flow and heat transmission in the presence of porous medium, heat radiation, and rate of heat generation. The computer program MATHEMATICA is used to emphasize the impact of each flow parameter. Graphs are used to analyze the results of radiation, heat source, magnetic, and nanoparticle volume fraction obtained using the Laplace transform technique for engineering variables like fraction and rate of heat, as well as velocity and thermal distribution. The velocity distribution is an increasing function of mixed convective parameter. Larger values of porosity variable and mixed convection variable result in accelerating the velocity of the fluid. Additionally, we conducted research with various ratios of nanoparticles and discovered several intriguing outcomes that can be used to solve various technical issues, particularly in the cooling process. [ABSTRACT FROM AUTHOR] more...

The digitalization of educational systems and the corresponding impact on the learners' improvement require modern pedagogical approaches to increase motivation among learners in distance learning. According to the literature, authentic e-learning and real-world themes create a dynamic learning setting and enhance learners' engagement; however, the impact of adopting authentic learning has not been investigated for deaf learners in a sign language e-learning setting. Therefore, this study aims to examine the effect of adopting authentic learning for the design of e-learning for deaf learners. The study employed a mixed-methods approach by conducting a one-group pre-test–post-test with 11 deaf learners and measuring design principles of authentic learning via semi-structured interviews. The statistical portion analyzed the T-test and Cohen's d-effect size, and the result showed that e-learning through authentic themes was significantly effective. The interview results revealed a positive attitude toward using e-learning based on an authentic learning approach, which increased deaf learners' motivation. It was found that e-learning based on an authentic sign language e-learning setting and technology enhances deaf learners' satisfaction and motivation with their first e-learning experience. [ABSTRACT FROM AUTHOR] more...

Background and Aim: Depression is thought to affect up to half of Parkinson's patients at some point during their illness, while anxiety is reported by about 40% of PD patients. The study aimed to assess the prevalence of depression and anxiety among patients with Parkinson's disease (PD) in Saudi Arabia. Methods: The study involved Saudi Arabian citizens and residents aged 40 or older with PD, who completed internet-survey (including online and email-based data collection) or telephone-survey by trained interviewers. We used the Parkinson's Disease Questionnaire for quality-of-Life assessment questionnaire (PDQ-39), Patient Health Questionnaire-9 for depression (PHQ-9), and General Anxiety Disorder-7 anxiety questionnaire (GAD-7). Results: The study included 46 participants, of whom 37% were aged 60– 69 years, 67% were male, 46% had completed a university education, and 87% were married. Depression symptoms were present in 84.8% of participants, while 73.9% experienced anxiety. PD patients lacking social support were 8 times more likely to develop major depression [OR = 8.27, 95% CI (1.47– 46.31), p = 0.016] and 5 times more likely to experience anxiety symptoms [OR = 5.36, 95% CI (1.14– 25.26), p = 0.034]. Those unable to perform daily living activities or who faced stigma had a 16.5 times higher likelihood of anxiety symptoms [OR = 16.5, 95% CI (1.62– 168.48), p = 0.018]. Furthermore, cognitive impairment increased the likelihood of anxiety by 11 times [OR = 11.43, 95% CI (1.83– 71.42), p = 0.009]. Conclusion: The study reveals a high prevalence of depression and anxiety among Parkinson's disease patients, linked to physical impairments and social isolation. Many patients report no mental health improvement despite treatment, highlighting the need for routine mental health assessments, social support, and tailored interventions to enhance their quality of life. The small sample size may limit the statistical power, precision, and generalizability of the study's findings. [ABSTRACT FROM AUTHOR] more...

Conjugate Gradient (CG) methods are widely used for solving large-scale nonlinear systems of equations arising in various real-life applications due to their efficiency in employing vector operations. However, the global convergence analysis of CG methods remains a significant challenge. In response, this study proposes scaled versions of CG parameters based on the renowned Barzilai-Borwein approach for solving convex-constrained monotone nonlinear equations. The proposed algorithms enforce a sufficient descent property independent of the accuracy of the line search procedure and ensure global convergence under appropriate assumptions. Numerical experiments demonstrate the efficiency of the proposed methods in solving large-scale nonlinear systems, including their applicability to accurately solving the inverse kinematic problem of a 3DOF robotic manipulator, where the objective is to minimize the error in achieving a desired trajectory configuration. [ABSTRACT FROM AUTHOR] more...

Background: Dexmedetomidine (DEX) is a highly favored sedative agent in critically ill patients owing to its anxiolytic and analgesic properties, lower risk of delirium, and minimal respiratory depression. Additionally, DEX exhibits anti-inflammatory properties, which have prompted its use in managing COVID-19 patients to mitigate cytokine storm and multi-organ dysfunction. Thus, this study aims to evaluate the safety and effectiveness of DEX use in critically ill patients with COVID-19. Method: This multicenter, retrospective cohort study included adult patients with confirmed COVID-19 who were admitted to the ICUs and did not require invasive mechanical ventilation (MV). Patients were categorized into two groups based on receiving DEX use within 72 h of ICU admission. The primary outcome was respiratory failure requiring invasive MV; other outcomes were considered secondary. Results: A total of 155 patients were included in the study after propensity matching. DEX did not reduce respiratory failure requiring invasive MV (HR 0.66; 95% CI (0.28, 1.53), P =.33). However, the time for invasive MV was statistically significantly shorter in the DEX group compared with the control group (beta coefficient (95%CI): - 1.05 (−2.03, −0.07), P =.03). In contrast, ICU and hospital Length of stay (LOS) were not statistically significant compared to the control group (beta coefficient 0.04 (95% CI −0.29, 0.38), P =.80, and beta coefficient - 0.03 (95% CI −0.33, 0.26), P =.81, respectively). In addition, the 30-day and in-hospital mortality rates were similar between the two groups (HR 1.1; 95% CI 0.97, 1.20, P =.14, and HR 1.01; 95% CI 0.95, 1.06, P =.90, respectively). Conclusion: Dexmedetomidine did not appear to lower the risk of respiratory failure necessitating invasive mechanical ventilation in critically ill patients. However, the mean time for invasive mechanical ventilation was shorter in the DEX group. Future interventional studies are required to confirm our findings. [ABSTRACT FROM AUTHOR] more...

Background: Judging the stability/activity of vitiligo is of therapeutic and prognostic significance. Clinical and biochemical activity indicators are available, but none is currently universally accepted. Objective: To compare the accuracy of patient-derived vitiligo disease activity score (VIDA) and dermoscopy, versus sequential planimetry in determining vitiligo stability/activity. Patients and methods: A total of 120 nonsegmental otherwise healthy vitiligo patients were included, who reported disease stability for the last 6 months. Global assessment and photography were followed by choosing a stable non-repigmenting lesion for longitudinal evaluation of planimetric changes, and dermoscopy. Patients received the standard protocol of narrow band ultraviolet B for 3 months, and patient recall for global and lesional progression was recorded. Accuracy of patient-derived VIDA and dermoscopic signs, versus planimetric changes as the reference were compared for judging vitiligo stability/activity. Results: Patient-derived VIDA showed 58.33% accuracy in determining disease stability while Dermoscopy showed 97.50% overall accuracy. The absence of a pigment network and the absence of signs of activity (collective absence of ill-defined border, satellite lesions, and microkoebnerization) showed 100% accuracy in establishing disease stability. On the other hand, the presence of any microkoebnerization, starburst sign, or satellite/tapioca sago sign was 100% indicative of activity. Border definition gave a 91.67% overall accuracy for judging stability, while Perifollicular pigmentation showed an accuracy of 49.17%. Conclusion: Patient-derived VIDA is generally unreliable, whereas longitudinal follow-up for planimetric changes, and dermoscopic assessment are of better reliability. The absence of pigment network, and collective absence of ill-defined border, microkoebnerization, and satellite lesions are 100% accurate in predicting stable vitiligo. [ABSTRACT FROM AUTHOR] more...

This article reports an Ultra wideband nano scale metamaterial absorber with ultrathin and flexible feature for visible spectrum applications. The absorber investigated for dispersion and Fano resonance characteristics to achieve metamaterial properties as well as independent of asymmetry of structure. Maximum visible spectrum wave interaction with the cascaded split nano square meta atom also ensured to achieve the absorption at highest percentage in numerical evaluation. The Finite Difference Time Domain (FDTD) method incorporated with CST microwave studio computational tool used for the entire analysis. Numerical analysis revealed that, on average 86.66% absorption achieved for 560 THz bandwidth peak absorption for the unit cell was 99.88% and the array shows 99.79%. Dispersion gap optimized based on mode 4 to incorporate all photons for phase and group velocity inside the nano metamaterial absorber. Furthermore, the Fano resonance wave to identify the high-quality factor at visible spectrum on nanostructure meta atom and direct-indirect visible wave trapped in the structure. The dispersion gap optimization and Fano resonance make the proposed cascaded split nano square meta atom a significant candidate for visible spectrum applications like solar energy harvesting, biochemical sensing, optical range application etc. [ABSTRACT FROM AUTHOR] more...

Resting state networks (RSNs) of the brain are characterized as correlated spontaneous time-varying fluctuations in the absence of goal-directed tasks. These networks can be local or large-scale spanning the brain. The study of the spatiotemporal properties of such networks has helped understand the brain's fundamental functional organization under healthy and diseased states. As we age, these spatiotemporal properties change. Moreover, RSNs exhibit neural plasticity to compensate for the loss of cognitive functions. This narrative review aims to summarize current knowledge from functional magnetic resonance imaging (fMRI) studies on age-related alterations in RSNs. Underlying mechanisms influencing such changes are discussed. Methodological challenges and future directions are also addressed. By providing an overview of the current state of knowledge in this field, this review aims to guide future research endeavors aimed at promoting healthy brain aging and developing effective interventions for age-related cognitive impairment and neurodegenerative diseases. [ABSTRACT FROM AUTHOR] more...