RESUMEN

Background & Objectives: Genotypic identification of the etiologic agents of vaginal candidiasis (VC) is of significance in epidemiologic studies and in the establishment of adequate treatment protocol. The aim of this study was to determine the antifungal susceptibility and gene diversity of C. albicans isolated from a group of Jordanian women with VC. Methods: A total of 312 isolates of candida species, recovered from women with vaginal candidiasis who attended gynecology clinics affiliated to three major private hospitals in Amman over a period of five months (July 2020 to December 2020) were included in this study. The isolated Candida were characterized by phenotypic and genotypic means. Genotypic studies were performed using specific PCR primers of the rDNA and RPS genes. Susceptibility testing of all C. albicans isolates was conducted following the National Committee for Clinical Laboratory Standards and E-test strips. Results: Candida albicans was the most dominant Candida spp. that caused VC among the studied population. C. albicans isolates were found to be of three different subtypes at the 25S rDNA gene. All isolates belonged to genotypes A, B and C while genotypes D and E were not detected. The diversity of C. albicans was higher on the basis of RPS region where the use of two markers (P-I and P-II) resulted in the identification of nine distinct C. albicans subtypes. The sensitivity testing revealed variations in the susceptibility of various genotypes to different antifungal drugs. Genotype A isolates were more susceptible to fluconazole, flucytosine and ketoconazole than genotypes B and C. Conclusion: Candida albicans incriminated as etiologic agents of vaginitis among Jordanian women exhibited relationship between various genotypes and antifungal drugs.

RESUMEN

A variety of parameters, including liquefaction and semen viscosity, affect the sperm's ability to travel and reach the egg for fertilization and conception. Given that the details behind the viscosity of the semen in male camels have not yet been fully clarified, the purpose of this study was to ascertain how the addition of papain affected the viscosity of fresh diluted camel semen. The study examined semen samples derived from camels that had distinct viscosities. Sperm motility, viability, abnormal sperm percentage, concentration, viscosity, morphometry, acrosome integrity and liquefaction were among the evaluations following 0, 5, 10, 20 or 30 min of incubation at 37°C with papain (0.004 mg/mL, 0.04 mg/mL or 0.4 mg/mL; a semen sample without papain was used as a control). A statistically significant interaction between the effects of papain concentrations and incubation time was found (F = 41.68, p = .0001). Papain concentrations (p = .0001) and incubation times (p = .0001) both had a statistically significant impact on viscosity, according to a simple main effects analysis. A lower viscosity was found (p < .05) at 0.04 mg/mL (0.1 ± 0.0) after 10 min of incubation. A simple main effects analysis showed that papain concentrations and incubation time have a statistically significant effect on sperm motility (p = .0001). At 0.04 mg/mL papain, the sperm motility % was higher (p < .05) after 10 min (64.4 ± 4.8), 20 min (68.4 ± 6.2), and 30 min incubation (72.2 ± 6.6) compared to 0, 5 min (38.3 ± 4.1 and 51.6 ± 5.0, respectively). In conclusion, the fresh diluted camel semen had the lowest viscosity properties after 10 min of incubation with 0.04 mg/mL papain, without compromising sperm motility, viability, acrosome integrity and sperm morphology.

Asunto(s)

RESUMEN

This study examines the effects of magnetic-field-dependent (MFD) viscosity on the boundary layer flow of a non-Newtonian sodium alginate-based Fe3O4 nanofluid over an impermeable stretching surface. The non-Newtonian Casson and homogeneous nanofluid models are utilized to derive the governing flow and heat transfer equations. Applying Lie group transformations to dimensional partial differential equations yields nondimensional ordinary differential equations, which are then numerically solved using the spectral quasi-linearization technique. The analysis primarily focuses on the impacts of the MFD viscosity parameter, nanoparticle volume fraction of Fe3O4, and magnetic parameters on the flow and heat transfer characteristics. The local skin friction and heat transfer rate behaviors influenced by viscosity changes due to the magnetic field are discussed. It is found that MFD viscosity significantly impacts flow and thermal energies, enhancing skin friction coefficients and reducing Nusselt numbers in the boundary layer region.

RESUMEN

The advancement of non-Newtonian nanofluid innovation is a crucial area of research for physicists, mathematicians, manufacturers, and materials scientists. In engineering and industries, the fluid velocity caused by rotating device and nanofluid has a lot of applications such as refrigerators, chips, heat ex-changers, hybrid mechanical motors, food development, and so on. Due to the tremendous usage of the non-Newtonian nanofluid, the originality of the current study is to explore the influence of nanoparticle radii and inter-particle spacing effects on the flow characteristics of Casson methanol-based aluminium alloy (AA7072) nanofluid through a rotating disc with Joule heating and magnetic dipole. The present problem is modeled in the form of partial differential equations (PDEs), and these PDEs are converted into ordinary differential equations with the help of suitable similarity transformations. The analytical solution to the current modeled problem has been obtained by using the homotopy analysis method (HAM) and numerical solutions are obtained by employing Runge-Kutta-Fehlberg method along with shooting technique. The main purpose of the present research work is to analyze the behavior of the velocity and temperature of the nanofluid for small and large radius of the aluminium alloy (AA7072) nanoparticles and inter-particle spacing. The radial and tangential velocities are enhanced due to rising ferro-hydrodynamic interaction parameter and the skin friction force for radial and tangential directions are enhanced 10.51% and 2.16% whenh= 0.5. Also, the heat transfer rate is reduced 18.71% and 16.70% whenh= 0.5% andRp= 1.5. In fact, the present results are compared with the published results and they met good agreement.

RESUMEN

Heat and mass transfer rate by using nanofluids is a fundamental aspect of numerous industrial processes. Its importance extends to energy efficiency, product quality, safety, and environmental responsibility, making it a key consideration for industries seeking to improve their operations, reduce costs, and meet regulatory requirements. So, the principal objective of this research is to analyze the heat and mass transfer rate for three-dimensional magneto hydrodynamic nanoliquid movement with thermal radiation and chemical reaction over the dual stretchable surface in the existence of an inclined magnetization, and viscous dissipation. The flow is rotating with constant angular speed [Formula: see text] about the axis of rotation because such flows occur in the chemical processing industry and the governing equations of motion, energy, and concentration are changed to ODEs by transformation. The complex and highly nonlinear nature of these equations makes them impractical to solve analytically so tackled numerically at MATLAB. The obtained numerical results are validated with literature and presented through graphs and tables. Increasing the Eckert number from [Formula: see text] a higher Nusselt and Sherwood number was noted for the hybrid nanofluid. By changing the angle of inclination [Formula: see text], the [Formula: see text] performance is noted at 8% for nanofluid and 33% for hybrid nanofluid. At the same time, [Formula: see text] performance of 0.5% and 2.0% are observed respectively. Additionally, as the angle of inclination increases the skin friction decreases and the chemical reaction rate increases the mass transmission rate.

RESUMEN

Symptomatic and asymptomatic individuals play a significant role in the transmission dynamics of novel Coronaviruses. By considering the dynamical behaviour of symptomatic and asymptomatic individuals, this study examines the temporal dynamics and optimal control of Coronavirus disease propagation using an epidemiological model. Biologically and mathematically, the well-posed epidemic problem is examined, as well as the threshold quantity with parameter sensitivity. Model parameters are quantified and their relative impact on the disease is evaluated. Additionally, the steady states are investigated to determine the model's stability and bifurcation. Using the dynamics and parameters sensitivity, we then introduce optimal control strategies for the elimination of the disease. Using real disease data, numerical simulations and model validation are performed to support theoretical findings and show the effects of control strategies.

Asunto(s)

RESUMEN

Introduction Thyroid cancer, one of the most frequently diagnosed endocrine malignancies, has witnessed a discernible global surge, predominantly among young adults. The etiological spectrum of thyroid cancer ranges from genetic mutations to environmental triggers. The early and precise detection of thyroid nodules (TNs) is crucial, given their latent potential for malignancy. Thyroid Imaging Reporting and Data System (TI-RADS) is an evidence-based stratification tool designed to standardize the assessment of TNs. Within this system, nodules categorized as TI-RADS 3 present an intermediate risk of malignancy, thereby necessitating meticulous evaluation. The objective of this study is to investigate the rates of cancer within thyroid nodules classified as TI-RADS 3, to determine the accuracy and effectiveness of the TI-RADS classification system in predicting malignancy at this intermediate-risk level, and to improve the diagnostic process and management strategies for these nodules. Methods A retrospective study was carried out on patients diagnosed with TI-RADS-3 thyroid nodules at King Fahad Hospital, Al-Hufof, between January 2019 and May 2023. Data were extracted from electronic medical records and encompassed patient demographics, and clinical and pathological details. Statistical analyses were performed using SPSS software version 27.0.1 (IBM Corp., Armonk, NY) examining the relationship between clinical characteristics and biopsy outcomes. Results The study involved 162 participants, mostly females (82.1%), with a median age of 43 years. Thyroid nodule analysis revealed 92.0% benign and 8.0% malignant cases, with the most common nodule size ranging from 2 to 2.4 cm. No significant correlation was found between clinical characteristics and biopsy results, indicating neither age nor gender significantly predicts malignancy in thyroid nodules within this cohort. Conclusion The majority of TI-RADS 3 nodules at King Fahad Hospital were benign. Yet, relying solely on TI-RADS for clinical decisions is not advised. An integrated approach, encompassing TI-RADS gradings and other nodule features, is essential for balanced patient management between intervention and observation.

RESUMEN

Repurposing existing drugs appears to be a potential solution for addressing the challenges in the treatment of non-small cell lung cancer (NSCLC). ß-adrenoceptor antagonist drugs (ß-blockers) have tumor-inhibiting effects, making them promising candidates for potential NSCLC treatment. This study investigates the anticancer potential of a subset of ß-blockers in NSCLC cell lines; A549 and H1299. Additionally, it investigates the underlying mechanism behind ß-blockers' anticancer effect by influencing a potential novel target named aldehyde dehydrogenase (ALDH). The MTT assay assessed ß-blockers' cytotoxicity on both cell lines, while Western blot and NADH fluorescence assays evaluated their influence on ALDH protein expression and activity. Carvedilol (CAR) was the most effective blocker in reducing cell survival of A549 and H1299 with IC50 of 18 µM and 13.7 µM, respectively. Significantly, CAR led to a 50% reduction in ALDH expression and 80% decrease in ALDH activity in A549 cells, especially when combined with ß-agonists, in comparison to the control. This effect might be attributed to ß-agonist blockade or an alternative pathway. This novel finding adds to our understanding of CAR's multifaceted anticancer properties, implying that combining CAR with ß-agonists could be a useful strategy for lung cancer treatment.

RESUMEN

Coronavirus disease 2019 (COVID-19) is a highly contagious respiratory disease that leads to variable degrees of illness, and which may be fatal. We evaluated the diagnostic performance of each chest computed tomography (CT) reporting category recommended by the Expert Consensus of the Radiological Society of North America (RSNA) in comparison with that of reverse transcription polymerase chain reaction (RT-PCR). We aimed to add an analysis of this form of reporting in the Middle East, as few studies have been performed there. Between July 2021 and February 2022, 184 patients with a mean age of 55.56 ± 16.71 years and probable COVID-19 infections were included in this retrospective study. Approximately 64.67% (119 patients) were male, while 35.33% (65 patients) were female. Within 7 days, all patients underwent CT and RT-PCR examinations. According to a statement by the RSNA, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of each CT reporting category were calculated, and the RT-PCR results were used as a standard reference. The RT-PCR results confirmed a final diagnosis of COVID-19 infection in 60.33% of the patients. For COVID-19 diagnoses, the typical category (n = 88) had a sensitivity, specificity, PPV, and accuracy of 74.8%, 93.2%, 94.3%, and 92.5%, respectively. For non-COVID-19 diagnoses, the PPVs for the atypical (n = 22) and negative (n = 46) categories were 81.8% and 89.1%, respectively. The PPV for the indeterminate (n = 28) category was 67.9%, with a low sensitivity of 17.1%. However, the RSNA's four chest CT reporting categories provide a strong diagnostic foundation and are highly correlated with the RT-PCR results for the typical, atypical, and negative categories, but they are weaker for the indeterminate category.

RESUMEN

Klein-Gordon equation characterizes spin-particles through neutral charge field within quantum particle. In this context, fractionalized Klein-Gordon equation is investigated for the comparative analysis of the newly presented fractional differential techniques with non-singularity among kernels. The non-singular and non-local kernels of fractional differentiations have been employed on Klein-Gordon equation for the development of governing equation. The analytical solutions of Klein-Gordon equation have been traced out by fractional techniques by means of Laplace transforms and expressed in terms of series form and gamma function. The data analysis of fractionalized Klein-Gordon equation is observed for Pearson's correlation coefficient, probable error and regression analysis. For the sake of comparative analysis of fractional techniques, 2D sketch, 3D pie chart, contour surface with projection and 3D bar sketch have been depicted on the basis of embedded parameters. Our results suggest that varying frequency has reversal trends for quantum wave and de Broglie wave.

RESUMEN

The non-linear mixed convective heat and mass transfer features of a non-Newtonian Casson liquid flow over a stretching surface are investigated numerically. The stretching surface is embedded in a Darcian porous medium with heat generation/absorption impacts. The fluid flow is assumed to be driven by both buoyancy and Arrhenius kinetics. The governing equations are modelled with the help of Boussinesq and Rosseland approximations. The similarity solutions of the non-dimensional equations are obtained using two numerical approaches, namely fourth fifth Runge - Kutta Fehlberg method and the shooting approach. The velocity, temperature and concentration profiles are discussed for important physical parameters through various graphical illustrations. The skin friction, the non-dimensional wall temperature, and the concentration expressions were derived and analysed. The results indicate that the increasing values of linear and nonlinear convection due to temperature, nonlinear convection due to concentration, and heat of reaction increase the dimensionless wall temperature. The dimensionless wall concentration rises with the increasing values of heat of reaction, linear and nonlinear convection due to temperature, and nonlinear convection due to concentration parameters.

RESUMEN

A steady, incompressible, two-dimensional Sisko-nanofluid flow towards the horizontal direction with no movement in the vertical direction is considered on a stretching/shrinking surface. The power law component (Sisko model) is incorporated under the regime of the porous medium. A magnetic impact is included coming from the MHD in the surface normal direction. In addition, thermal radiation, Brownian diffusion, and thermophoresis are involved in the governing system of equations obtained from the Navier-Stokes model in two-dimensional flow systems. The PDEs are converted into the one-dimensional system using suitable transformations and solved by Galerkin weighted residual method validated with the spectral collocation method. The optimization analysis is performed on heat transfer and skin-friction factors using response surface methodology. The impact of the parameters involved in the model has been testified and is provided in graphical forms. The outcomes indicate that for the values of the porosity factor fluctuating between [0, 2.5], the velocity profile and corresponding boundary layer thickness are lesser towards the maximum value of the parameter, and the results are opposite as the parameter approaches zero. The optimization and sensitivity analysis shows that the transport of heat sensitivity towards thermal radiation, Brownian diffusion, and thermophoresis declined whenever the Nt and Nb increased from low to high and at the medium level of thermal radiation. An increment in the Forchheimer parameter increases the sensitivity of the rate of friction factor, whereas increasing the Sisk-fluid parameter has the reverse effect. Elongation processes like those of pseudopods and bubbles make use of such models. The idea is also widely used in other sectors, such as the textile industry, glass fiber production, cooling baths, paper manufacture, and many more.

RESUMEN

BACKGROUND: Apitherapy is an emerging field in cancer research, particularly in developing communities. The potency of Melittin (MEL), a major constituent in bee venom is accounted for the cytotoxic capacity against cancer cells. It is postulated that the genotype of bees and the time of venom collection influences its specific activity against certain types of cancer. METHOD: Hereby, Jordanian crude bee venom (JCBV) was collected during different seasons of the year, specifically spring, summer and autumn and investigated for in vitro antitumour effects. Venom collected during springtime comprised the highest quantity of MEL in comparison to venom collected some other time. Springtime-collected JCBV extract and MEL were tested on an immortal myelogenous leukaemia cell line, namely K562 leukemic cells. Treated cells were examined for cell modality via flow cytometry analysis and cell death mediating gene expressions. RESULTS: Springtime-collected JCBV extract and MEL showed an IC50 of 3.7 ± 0.37 µg/ml and 1.84 ± 0.75 µg/ml, respectively. In comparison to JCBV and positive control, MEL-treated cells exhibited late apoptotic death with a moderate cellular arrest at G0/G1 and an increase of cell number at G2/M phase. Expression of NF-κB/MAPK14 axis was inhibited in MEL and JCBV-treated cells, as well as expression of c-MYC and CDK4. Moreover, marked upregulation in ABL1, JUN and TNF was observed. In conclusion, springtime-collected JCBV showed the highest content of MEL while both JCBV and pure MEL showed apoptotic, necrotic, and cell cycle arrest efficiency against K562 leukemic cells. CONCLUSION: Integration of bee venom in chemotherapy needs more investigation and should be carefully translated into clinical use. During such translation, the correlation of bee genotype, collection time and concentration of MEL in CBV should be profiled.

Asunto(s)

RESUMEN

Urinary tract infections (UTIs) are one of the most common long-term complications of diabetes mellitus (DM). Additionally, various factors, such as socio-demographics, type of DM, fasting blood glucose, regular diabetes monitoring, comorbid chronic diseases, HbA1c, body mass index (BMI), and duration of DM, are also thought to predispose individuals to developing UTIs more frequently when they have DM. This research aims to evaluate the risk factors for UTIs and their prevalence among people with DM in Saudi Arabia (KSA). This cross-sectional study was conducted among 440 adults with type 1, type 2, and gestational DM. The participants had to be at least 18 years old, of both genders, and had been suffering from DM for any period of time. A self-administered questionnaire was utilized to collect data on demographic characteristics, such as sex, age, height, weight, material state, education level, income, and clinical profiles of DM and UTI. The crude (COR) and adjusted odds ratios (AOR) were calculated using logistic regression in the IBM SPSS software. The incidence of types 1 and 2 DM and gestational diabetes reached 34.1, 60.9, and 5%, respectively. Most of the participants had first-degree relatives with DM (65.9%). UTI was common in 39.3% of participants. A chi-squared statistical analysis revealed that the frequency of UTI varied depending (χ2 = 5.176, P = 0.023) on the type of DM. Burning urination and abdominal pain were the most common symptoms. The CORs for sex, marital status, hypertension, and BMI were significant (P < 0.05) and had values of 2.68 (95% CI = 1.78-4.02), 0.57 (95% CI = 0.36-0.92), 1.97 (95% CI = 1.14-3.43), and 2.83 (95% CI = 1.19-2.99), respectively. According to the adjusted model, only sex influenced the occurrence of UTIs. The AOR for sex was 3.45 (95% CI = 2.08-5.69). Based on this study, the authorities related to the health of DM patients can use its findings to guide awareness programs and clinical preparedness.

RESUMEN

BACKGROUND: Blunt abdominal trauma is a prevailing cause of pediatric morbidity and mortality. It constitutes the most frequent type of pediatric injuries. Contrast-enhanced sonography (CEUS) and contrast-enhanced computed tomography (CECT) are considered pivotal diagnostic modalities in hemodynamically stable patients. AIM: To report the experience in management of pediatric split liver and spleen injuries using CEUS and CECT. PATIENTS AND METHODS: This study included 246 children who sustained blunt abdominal trauma, and admitted and treated at three tertiary hospitals in the period of 5 years. Primary resuscitation was offered to all children based on the advanced trauma and life support (ATLS) protocol. A special algorithm for decision-making was followed. It incorporated the FAST, baseline ultrasound (US), CEUS, and CECT. Patients were treated according to the imaging findings and hemodynamic stability. RESULTS: All 246 children who sustained a blunt abdominal were studied. Patients' age was 10.5 ± 2.1. Road traffic accidents were the most common cause of trauma; 155 patients (63%). CECT showed the extent of injury in 153 patients' spleen (62%) and 78 patients' liver (32%), while the remaining 15 (6%) patients had both injuries. CEUS detected 142 (57.7%) spleen injury, and 67 (27.2%) liver injury. CONCLUSIONS: CEUS may be a useful diagnostic tool among hemodynamically stable children who sustained low-to-moderate energy isolated blunt abdominal trauma. It may be also helpful for further evaluation of uncertain CECT findings and follow-up of conservatively managed traumatic injuries.

Asunto(s)

RESUMEN

A novel analysis of the electromagnetohydrodynamic (EMHD) non-Newtonian nanofluid blood flow incorporating CuO and Al2O3 nanoparticles through a permeable walled diseased artery having irregular stenosis and an aneurysm is analyzed in this paper. The non-Newtonian behavior of blood flow is addressed by the Casson fluid model. The effective viscosity and thermal conductivity of nanofluids are calculated using the Koo-Kleinstreuer-Li model, which takes into account the Brownian motion of nanoparticles. The mild stenosis approximation is employed to reduce the bi-directional flow of blood to uni-directional. The blood flow is influenced by an electric field along with a magnetic field perpendicular to the blood flow. The governing mathematical equations are solved using Crank-Nicolson finite difference approach. The model has been developed and validated by comparing the current results to previously published benchmarks that are peculiar to this study. The results are utilized to investigate the impact of physical factors on momentum diffusion and heat transfer. The Nusselt number escalates with increasing CuO nanoparticle diameter and diminishing the diameter of Al2O3 nanoparticles. The relative % variation in Nusselt number enhances with Magnetic number, whereas a declining trend is obtained for the electric field parameter. The present study's findings may be helpful in the diagnosis of hemodynamic abnormalities and the fields of nano-hemodynamics, nano-pharmacology, drug delivery, tissue regeneration, wound healing, and blood purification systems.

RESUMEN

This research examined machine learning (ML) techniques for predicting the compressive strength (CS) of self-compacting concrete (SCC). Multilayer perceptron (MLP), bagging regressor (BR), and support vector machine (SVM) were utilized for analysis. A total of 169 data points were retrieved from the various published articles. The data set was based on 11 input parameters, such as cement, limestone, fly ash, ground granulated blast-furnace slag, silica fume, rice husk ash, coarse aggregate, fine aggregate, superplasticizers, water, viscosity modifying admixtures, and one output with compressive strength of SCC. In terms of properly predicting the CS of SCC, the BR technique outperformed both the SVM and MLP models, as determined by the research results. In contrast to SVM and MLP, the coefficient of determination (R2) for the BR model was 0.95, whereas for SVM and MLP, the R2 was 0.90 and 0.86, respectively. In addition, a k-fold cross-validation approach was adopted to check the accuracy of the employed models. The statistical measures mean absolute percent error, mean absolute error, and root mean square error ensure the validity of the model. Using sensitivity analysis, the influence of input factors on the intended CS of SCC was also explored. This analysis reveals that the highest contributing parameter towards the CS of SCC was cement with 16.2%, while rice husk ash contributed the least with 4.25% among all the input variables.

RESUMEN

Estimating concrete properties using soft computing techniques has been shown to be a time and cost-efficient method in the construction industry. Thus, for the prediction of steel fiber-reinforced concrete (SFRC) strength under compressive and flexural loads, the current research employed advanced and effective soft computing techniques. In the current study, a single machine learning method known as multiple-layer perceptron neural network (MLPNN) and ensembled machine learning models known as MLPNN-adaptive boosting and MLPNN-bagging are used for this purpose. Water; cement; fine aggregate (FA); coarse aggregate (CA); super-plasticizer (SP); silica fume; and steel fiber volume percent (Vf SF), length (mm), and diameter were the factors considered (mm). This study also employed statistical analysis such as determination coefficient (R2), root mean square error (RMSE), and mean absolute error (MAE) to assess the performance of the algorithms. It was determined that the MLPNN-AdaBoost method is suitable for forecasting SFRC compressive and flexural strengths. The MLPNN technique's higher R2, i.e., 0.94 and 0.95 for flexural and compressive strength, respectively, and lower error values result in more precision than other methods with lower R2 values. SHAP analysis demonstrated that the volume of cement and steel fibers have the greatest feature values for SFRC's compressive and flexural strengths, respectively.

RESUMEN

The present investigation aims to analyze higher-order endothermic/exothermic chemical reactions with activation energy by considering thermophoresis and Brownian motion effects on MHD mixed convective flow across a vertical stretching surface. The influence of velocity slip, thermal slip, and concentration slip along with an inclined external magnetic field is also considered. The governing coupled non-linear partial differential equations are transformed into ordinary differential equations using similarity transformation. The resulting system of non-linear ODEs is solved by the Newton Raphson shooting technique using the RK-4 algorithm. The impact of various physical parameters discovered in the problem viz. endothermic/exothermic reaction variable, thermophoresis parameter, activation energy parameter, Brownian motion parameter, chemical reaction parameter have been analyzed on velocity profile, temperature profile, and concentration profile. The effects of these parameters on skin-friction coefficient, Nusselt number, and Sherwood number are displayed in tabular form as well as surface plots. The impact of various physical parameters that appeared in the entropy generation is shown using surface and contour plots. The numerical findings are in good agreement with the previously published results. It is observed that an increment in thermophoresis and Brownian motion parameters results in a declination of entropy profiles, whereas an increment in Bejan number profiles is observed. A small region near the surface exhibits an inclination in concentration profiles with an increase in the order of the chemical reaction. In contrast, the opposite effect is analyzed near the boundary layer. Also, the contour and surface plots are displayed to portray real-world applications in industrial and technical processes and the physical depiction of flow characteristics that arise in the current study.

RESUMEN

INTRODUCTION: Nanofluids are considered a better alternative to conventional fluids in many industrial situations and unfolding new opportunities for various applications owing to the optical and thermal properties of additive nanosized materials. OBJECTIVES: In this study, the thermal and hydraulic characteristics of a Casson-based (sodium alginate) multiwall carbon nanotube (MWCNT) nanofluid were computationally investigated inside a wavy square enclosure containing a circular-shaped obstacle. The square enclosure comprised two cooled vertical walls and a wavy adiabatic top wall. The central part of the bottom wall comprised a heated wavy structure, and the remaining parts exhibited a flat and adiabatic structure. METHODS: The Navier-Stokes (N-S) equations and boundary conditions were established using the non-Newtonian Casson fluid model and Rosseland thermal radiation. The present problem was numerically simulated using the Galerkin finite element method for three types of obstacles, namely, adiabatic, hot, and cold. The impacts of Casson parameter (0.001 ≤ ß ≤ 0.1), Rayleigh number (103 ≤ Ra ≤ 106), nanoparticle volume fraction (0.01 ≤ φ ≤ 0.1) and radiation parameter (1 ≤ Rd ≤ 4) are analysed. A numerical code validation was performed using the available benchmark results. RESULTS: The characteristics of the convective radiation heat transport were clearly analyzed through the stream function and isotherm plots. For all types of obstacles, the mean Nusselt number along the heated wavy wall increased with the Casson parameter, MWCNT volume fraction, Rayleigh number, and radiation parameter. CONCLUSION: The heat and flow characteristics of a Casson-based MWCNT nanofluid inside a wavy square enclosure were investigated. The mean Nusselt number was higher (lower) in the presence of cold (hot) obstacles.

Asunto(s)