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This study investigates the computational analysis of steady, incompressible, natural convection airflow in a 2D equilateral triangular cavity featuring two stationary cold circular cylinders. The convective phenomena within the cavity have been observed under the variation of uniform porosity. The convective flow has been modeled using the Darcy-Brinkman formulations for porous medium incorporated with the Boussinesq approximation. The governing equations have been simulated using the finite element method with non-uniform triangular meshing. The investigation was conducted with a fixed Prandtl number, Pr = 0.71, and different porosity by varying Darcy number, Da = 10–5 to 10–2. The convective strength has been varied with the Rayleigh number, Ra = 103 to 106, and the length of the heated and cold segment, ε = 0.1 to 0.9. Results regarding the fluid flow and temperature distribution are visualized through streamlines and isotherms. The quantity and the quality of heat transfer (HT) have been investigated, respectively, by the Nusselt number (Nu) and the entropy generation (Egen). The results reveal that an increase in the length of the hot wall (ε) significantly reduces HT. Also, Egen increases with the length of active segments (ε), while the Bejan number (Be) consistently rises when the Darcy-Rayleigh (Da-Ra) number increases, i.e., Da-Ra≥102. The maximum HT rate was obtained within the range of Da = 10–5 to 10–3 for a constant value of ε. Furthermore, the maximum HT was obtained for the smallest value ε for any value of Da or Ra.

The application of remote sensing, which is non-destructive and cost-efficient, has been widely used in crop monitoring and management. This study used a built-in multispectral imager on a small unmanned aerial vehicle (UAV) to capture multispectral images in five different spectral bands (blue, green, red, red edge, and near-infrared), instead of satellite-captured data, to monitor soybean growth in a field. The field experiment was conducted in a soybean field at the Mississippi State University Experiment Station near Pontotoc, MS, USA. The experiment consisted of five cover crops (Cereal Rye, Vetch, Wheat, Mustard plus Cereal Rye, and native vegetation) planted in the winter and three fertilizer treatments (Fertilizer, Poultry Liter, and None) applied before planting the soybean. During the soybean growing season in 2022, eight UAV imaging flyovers were conducted, spread across the growth season. UAV image-derived vegetation indices (VIs) coupled with machine learning (ML) models were computed for characterizing soybean growth at different stages across the season. The aim of this study focuses on monitoring soybean growth to predict yield, using 14 VIs including CC (Canopy Cover), NDVI (Normalized Difference Vegetation Index), GNDVI (Green Normalized Difference Vegetation Index), EVI2 (Enhanced Vegetation Index 2), and others. Different machine learning algorithms including Linear Regression (LR), Support Vector Machine (SVM), and Random Forest (RF) are used for this purpose. The stage of the initial pod development was shown as having the best predictability for earliest soybean yield prediction. CC, NDVI, and NAVI (Normalized area vegetation index) were shown as the best VIs for yield prediction. The RMSE was found to be about 134.5 to 511.11 kg ha−1 in the different yield models, whereas it was 605.26 to 685.96 kg ha−1 in the cross-validated models. Due to the limited number of training and testing samples in the K-fold cross-validation, the models’ results changed to some extent. Nevertheless, the results of this study will be useful for the application of UAV remote sensing to provide information for soybean production and management. This study demonstrates that VIs coupled with ML models can be used in multistage soybean yield prediction at a farm scale, even with a limited number of training samples.

This study investigates the computational analysis of steady, incompressible, natural convection airflow in a 2D equilateral triangular cavity featuring two stationary cold circular cylinders. The convective phenomena within the cavity have been observed under the variation of uniform porosity. The convective flow has been modeled using the Darcy-Brinkman formulations for porous medium incorporated with the Boussinesq approximation. The governing equations have been simulated using the finite element method with non-uniform triangular meshing. The investigation was conducted with a fixed Prandtl number, Pr = 0.71, and different porosity by varying Darcy number, Da = 10-5 to 10-2. The convective strength has been varied with the Rayleigh number, Ra= 10³ to 106, and the length of the heated and cold segment, ε = 0.1 to 0.9. Results regarding the fluid flow and temperature distribution are visualized through streamlines and isotherms. The quantity and the quality of heat transfer (HT) have been investigated, respectively, by the Nusselt number (Nu) and the entropy generation (Egen). The results reveal that an increase in the length of the hot wall (ε) significantly reduces HT. Also, Egen increases with the length of active segments (ε), while the Bejan number (Be) consistently rises when the Darcy-Rayleigh (Da-Ra) number increases, i.e., Da-Ra ≥ 10². The maximum HT rate was obtained within the range of Da = 10-5 to 10-3 for a constant value of ε. Furthermore, the maximum HT was obtained for the smallest value ε for any value of Da or Ra. [ABSTRACT FROM AUTHOR]

Aim: Malnutrition and infectious diseases, such as helminthic infections, are widespread among primary school children, especially in low‐ and middle‐income countries. However, there are limited studies on school health in Bangladesh, particularly in rural settings. This study aimed to explore the nutritional status and prevalence of helminthic infections in relation to associated health behavior, awareness, and knowledge regarding malnutrition and helminthic infections which were evaluated by school nurses among primary school children in Bangladesh. Methods: This was a descriptive, cross‐sectional survey study with a total duration of 1 month, from September to October, 2021. This study formed part of a school nurse project as a cluster non‐randomized clinical trial in Bangladesh. Selected variables from that clinical trial were analyzed and reported in the results section. The study participants were primary school children from four schools in rural Bangladesh. Results: In total, 604 children participated in the baseline survey and health checkups. Among them, 163 (27.0%) children were classified as malnourished according to the World Health Organization growth reference standard 2007. The prevalence of helminthic infections was 53 (8.8%). Approximately >50% of the children responded that they never/rarely practiced hygiene‐related behaviors and had no awareness and knowledge regarding malnutrition and helminthic infections. However, differences between the variables were not statistically significant. Conclusion: Children's nutritional status and prevalence of helminthic infections with related deprived health behaviors, and minimal awareness and knowledge, reinforce the importance of implementing educational interventions in the future. [ABSTRACT FROM AUTHOR]

Primary antiphospholipid syndrome (PAPS) is a systemic autoimmune disorder, characterised by consistently high levels of antiphospholipid antibodies, thrombosis, and/or pregnancy morbidity. Due to various suspected causes, deficient or insufficient levels of vitamin D in the serum have been reported in patients with PAPS; however, the reports have been sporadic and inconclusive. This systematic review and meta-analysis aimed to comprehensively evaluate the serum vitamin D levels in patients with PAPS compared to controls. A protocol was registered in PROSPERO (Registration No. CRD42019132128) and a systematic literature search was conducted through Google Scholar, PubMed, Web of Science, Scopus, and ScienceDirect databases without restricting language and year. Pooled prevalence, mean difference (MD), and odds ratio (OR) along with 95% confidence intervals (CI) were determined by using a random effects model. Study quality was assessed by the Joana Brigg’s Institute (JBI) protocol and publication bias was evaluated by a trim and fill funnel plot, Begg’s, and Egger’s tests. The pooled prevalence of vitamin D deficiency and insufficiency was found to be 32.2% [95% CI: 16.3–48.2] and 61.5% [95% CI: 40.2–82.8], respectively. Serum levels of vitamin D were considerably lower in the PAPS patients compared to controls (MD: −5.75, 95% CI: −9.73 to −1.77; p = 0.005). Multiple sensitivity analyses showed that the results remained statistically significant, demonstrating the robustness of this meta-analysis. No significant publication bias was detected in determining the MD of serum vitamin D levels in PAPS and controls. In conclusion, PAPS patients had greater rates of vitamin D deficiency or insufficiency, higher frequency of thrombosis, and lower serum vitamin D levels than healthy individuals.

Zika virus (ZIKV) and chikungunya virus (CHIKV) are arthropod-borne viruses with significant pathogenicity, posing a substantial health and economic burden on a global scale. Moreover, ZIKV-CHIKV coinfection imposes additional therapeutic challenges as there is no specific treatment for ZIKV or CHIKV infection. While a growing number of studies have documented the ZIKV-CHIKV coinfection, there is currently a lack of conclusive reports on this coinfection. Therefore, we performed a systematic review and meta-analysis to determine the true statistics of ZIKV-CHIKV coinfection in the global human population. Relevant studies were searched for in PubMed, Scopus, and Google Scholar without limitation in terms of language or publication date. A total of 33 studies containing 41,460 participants were included in this meta-analysis. The study protocol was registered with PROSPERO under the registration number CRD42020176409. The pooled prevalence and confidence intervals of ZIKV-CHIKV coinfection were computed using a random-effects model. The study estimated a combined global prevalence rate of 1.0% [95% CI: 0.7–1.2] for the occurrence of ZIKV-CHIKV coinfection. The region of North America (Mexico, Haiti, and Nicaragua) and the country of Haiti demonstrated maximum prevalence rates of 2.8% [95% CI: 1.5–4.1] and 3.5% [95% CI: 0.2–6.8], respectively. Moreover, the prevalence of coinfection was found to be higher in the paediatric group (2.1% [95% CI: 0.0–4.2]) in comparison with the adult group (0.7% [95% CI: 0.2–1.1]). These findings suggest that the occurrence of ZIKV-CHIKV coinfection varies geographically and by age group. The results of this meta-analysis will guide future investigations seeking to understand the underlying reasons for these variations and the causes of coinfection and to develop targeted prevention and control strategies.