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Malaria infection prevalence and diagnostic performance of the Abbott Bioline Malaria Ag P.f/Pan rapid test in rural populations of Central Cameroon
Abstract In Cameroon, the management of uncomplicated malaria cases in the communities and in low-resource health facilities rely on the use of reliable rapid diagnostic tests (RDTs). This work was undertaken to determine the trend in human malaria infection in rural settings of Central Cameroon and assess the diagnostic performance of Abbott Bioline Malaria Ag P.f/Pan RDT recommended by the National Malaria Control Programme (NMCP). Cross-sectional surveys were conducted in March 2022 and May 2024. Plasmodium infection was detected using RDT and microscopy techniques, and with real-time PCR for validation of discordant results. Sensitivity (Se), specificity (Sp), positive and negative predictive values, positive and negative likelihood ratios (LR + and LR-), accuracy and agreement were calculated to assess the performance of the RDT. Plasmodium infection prevalence was 64.9% and 71.7% by microscopy and RDT, respectively, Plasmodium falciparum being the predominant species (microscopy:97.48%). With microscopy as reference, the RDT showed high sensitivity (Se:93.37%; CI:91.15%-95.77%) and low specificity (Sp: 68.50%; CI:62.40%-74.17%) for the detection of P. falciparum infection. The positive and negative predictive values were respectively 84.43% (CI:81.01%-87.46%) and 85.71% (CI:80.13%-90.22%). The RDT showed a small positive likelihood ratio (LR + = 2.96; CI:2.47-3.5734), a good negative likelihood ratio (LR-=0.09; CI:0.06–0.13) and moderate agreement (k = 0.652; CI:0.593–0.710; P < 0.001) with microscopy. The RDT showed higher sensitivity (81.48% vs. 48.14%), accuracy (0.75 and vs. 0.50), and agreement (AC1 = 0.715 vs. 0.371) than microscopy. The Abbott Bioline Malaria Ag P.f/Pan RDT demonstrated a high level of agreement with the most sensitive qPCR technique compared to microscopy. These findings further support its use as a reliable malaria diagnostic tool in the highly endemic setting of Central Cameroon.
The retina as a window into detecting subclinical cardiovascular disease in type 2 diabetes
Abstract Individuals with Type 2 Diabetes (T2D) are at high risk of subclinical cardiovascular disease (CVD), potentially detectable through retinal alterations. In this single-centre, prospective cohort study, 255 asymptomatic adults with T2D and no prior history of CVD underwent echocardiography, non-contrast coronary computed tomography and cardiovascular magnetic resonance. Retinal photographs were evaluated for diabetic retinopathy grade and microvascular geometric characteristics using deep learning (DL) tools. Associations with cardiac imaging markers of subclinical CVD were explored. Of the participants (aged 64 ± 7 years, 62% males); 200 (78%) had no diabetic retinopathy and 55 (22%) had mild background retinopathy. Groups were well-matched for age, sex, ethnicity, CV risk factors, urine microalbuminuria, and serum natriuretic peptide and high-sensitivity troponin levels. Presence of retinopathy was associated with a greater burden of coronary atherosclerosis (coronary artery calcium score ≥ 100; OR 2.63; 95% CI 1.29–5.36; P = 0.008), more concentric left ventricular remodelling (OR 3.11; 95% CI 1.50–6.45; P = 0.002), and worse global longitudinal strain (OR 2.32; 95% CI 1.18–4.59; P = 0.015), independent of key co-variables. Early diabetic retinopathy is associated with a high burden of coronary atherosclerosis and markers of early heart failure. Routine diabetic eye screening may serve as an effective alternative to currently advocated screening tests for detecting subclinical CVD in T2D, presenting opportunities for earlier detection and intervention.
The need for guardrails with large language models in pharmacovigilance and other medical safety critical settings
Efficacy of Stb resistance genes and pathotype diversity in Zymoseptoria tritici from Ethiopia
Abstract Zymoseptoria tritici, the causal agent of Septoria tritici blotch (STB) in bread wheat (Triticum aestivum), leads to significant global yield losses. Resistance breeding is vital for managing STB, but there is limited information on Z. tritici infection behaviour in Ethiopia. This study examined the virulence variability of Z. tritici isolates from Ethiopia’s Central Highlands and evaluated the effectiveness of known wheat STB-resistance genes. Eight wheat lines were tested against six Z. tritici isolates, showing significant differences (p < 0.0001) in necrotic leaf area (%NLA) and pycnidia coverage (%PC) among the tested Z. tritici isolates, wheat lines and their interactions. Wheat genotype TE9111 exhibited specific resistance to 50% of the isolates, while Taichung 29 showed no resistance. Isolate ZSE158 was the most aggressive, causing 61.4% PC and 54% NLA. The Ethiopian isolates displayed broad virulence against resistance genes, including Stb2 – Stb7. TE9111, carrying Stb11, showed resistance to 50% of isolates, making it a valuable source for resistance breeding against STB. This study identified highly virulent pathogen isolates useful for wheat germplasm screening for STB resistance and also key resistance source materials for use in wheat resistance breeding in Ethiopia.
Towards more effective nature-based climate solutions in global forests
A pilot study on the hemodynamic effects of negative pressure ventilation in patients after cardiac surgery focussing on right ventricular function
Reliability enhancement of EM-based tuning of microwave components using regularized operating band scanning
Abstract Numerical optimization is ubiquitous in contemporary microwave passive component design. Reliable quantification of electromagnetic (EM) cross-coupling, substrate losses, or environmental effects (e.g., connectors, housing) is impossible using analytical or equivalent network models. Consequently, the designs rendered using such tools must be further tuned at the EM simulation level. Although local algorithms are predominantly employed for this purpose, they are likely to fail if the starting point is of insufficient quality. On the other hand, global search techniques are associated with tremendous computational expenses. This study suggests an innovative technique for immunizing local algorithms against poor starting points, enabling their quasi-global search capability. The presented methodology reformulates the underlying optimization task by evaluating the circuit performance concerning the target operating bands scanned within the predefined ranges and by adding penalty factors proportional to the distance between the original and the scanned targets. The penalized objective is computed as the minimum of the above combination over the entire scanning range. As a result, the design specifications become attainable through local optimization over considerably broader frequency spectra at the expense of only a slight increase in the algorithm running costs. The presented approach is comprehensively verified using several microstrip components and the sensitivity-based routine as the search algorithm. The results unanimously showcase the ability of the procedure to allocate the optimum even under troublesome scenarios (poor initial points), which are unmanageable by conventional algorithms.
Genetic diversity and structure of Asian cowpea germplasm
Abstract Cowpea (Vigna unguiculata L. Walp., 2n = 2x = 22) is a vital dryland legume crop, renowned for its affordable dietary protein and essential nutrients for humans and animals. Cowpea originated in Africa and spread to various parts of the world through human migration, eventually reaching Asia. However, genetic diversity and structure in Asia cowpea remain poorly understood. This study utilized 6334 SilicoDArT and 14,482 single nucleotide polymorphism (SNP) markers to assess the genetic diversity and population structure of 405 cowpea accessions from 17 different countries, sourced from the National Agriculture and Food Research Organization (NARO) genebank in Japan. We used population structure, principal component analysis, discriminant analysis of principal components, and phylogenetic tree analysis to group the accessions into two main genetic populations. The accessions were further classified into six subgroups of African and Asian populations, corresponding to the geographical origins of the accessions. South Asian accessions showed the highest differentiation, with Nepalese accessions forming a distinct group along with Japanese accessions, highlighting that the rich genetic resources preserved within these regions may harbor valuable traits for breeding. In contrast, Southeast Asian and West African accessions exhibited low to moderate differentiation, suggesting recently shared genetic ancestry. AMOVA demonstrated that most genetic variation existed within accessions, while variation between populations was minimal. These findings highlight the rich genetic potential within the Asian cowpea germplasm, particularly in Nepalese and Japanese accessions. This study provides critical insights into breeding strategies aimed at enhancing the adaptability and productivity of cowpea in diverse environments.
A new band selection approach integrated with physical reflectance autoencoders and albedo recovery for hyperspectral image classification
Abstract Hyperspectral imaging has emerged as a powerful tool for remote sensing applications, offering rich spectral information across a broad electromagnetic spectrum. However, the high dimensionality of hyperspectral data poses significant challenges in analysis and interpretation. In this study, we propose a novel approach for hyperspectral image processing, focusing on dimensionality reduction, albedo recovery, and subsequent classification. Our method begins with a grouping strategy based on the electromagnetic spectrum that considers the images’ physical properties, facilitating the segmentation of hyperspectral data into meaningful spectral bands. This grouping reduces the dimensionality of the data and preserves crucial spectral information. Subsequently, we integrate autoencoders to incorporate non-linear transformations in the feature extraction phase, thereby improving the model’s capacity to learn intricate patterns within the data. A key goal of our methodology is to effectively embed spatial information into the representation. Albedo recovery is employed aimed at improving spatial resolution while retaining spectral fidelity. By leveraging the reduced-dimensional representation obtained through grouping and autoencoders, we reconstruct the hyperspectral image with enhanced spatial details, thereby facilitating more accurate interpretation and analysis. To assess the performance of the proposed approach, we perform experiments using three standard hyperspectral datasets: Indian Pines, University of Pavia, and Salinas.
Harnessing the power of S/N-doped NiO nanoparticles through bandgap tuning to achieve enhanced photocatalytic and antibacterial performances
Land use shapes riverine nutrient and sediment concentrations on Moorea, French Polynesia
Abstract Human activities drive changes in freshwater ecosystems by altering biogeochemical cycles. Freshwater networks provide important ecosystem services to human societies by purifying water and serving as an intermediary between terrestrial and marine systems. On high volcanic tropical islands, human activities are compartmentalized by steep terrain that delineates watershed boundaries. Patterns of land use affect adjacent stream ecosystems through runoff of sediment and nutrients, which fluctuates in the tropics as a result of seasonal rainfall. Here, we sought to reveal human impacts on nutrient and sediment regimes of tropical rivers by tracking patterns of river chemistry across a series of watersheds on Moorea, French Polynesia, between 2018 and 2019. Repeated sampling of rivers across a gradient of human activities revealed that water chemistry varied seasonally and with respect to rainfall and land use. In particular, dissolved inorganic nitrogen was more concentrated in rivers of watersheds with higher amounts of land clearing during the rainy season, and total suspended solids and phosphate were higher when recent rainfall was high. Importantly, the water quality of the rivers on Moorea repeatedly exceeded safe water quality standards established for similar high tropical islands in the Pacific. Our results show that differential land use across the landscape can have a substantial impact on the amounts of nutrients and sediment that tropical rivers transport, which on tropical islands could facilitate movement of materials from land to sea as precipitation increases with intensifying climate change.
Quantum correlations of spontaneous two-photon emission from a quantum dot
Allosteric modulation and biased signalling at free fatty acid receptor 2
Overburden failure characteristics and fracture evolution rule under repeated mining with multiple key strata control
A successive framework for brain tumor interpretation using Yolo variants
Abstract Accurate identification and segmentation of brain tumors in Magnetic Resonance Imaging (MRI) images are critical for timely diagnosis and treatment. MRI is frequently used to diagnose these disorders; however medical professionals find it challenging to manually evaluate MRI pictures because of time restrictions and unpredictability. Computerized methods such as R-CNN, attention models and earlier YOLO variants face limitations due to high computational demands and suboptimal segmentation performance. To overcome these limitations, this study proposes a successive framework that evaluates YOLOv9, YOLOv10, and YOLOv11 for tumor detection and segmentation using the Figshare Brain Tumor dataset (2100 images) and BraTS2020 dataset (3170 MRI slices). Preprocessing involves log transformation for intensity normalization, histogram equalization for contrast enhancement, and edge-based ROI extraction. The models were trained on 80% of the combined dataset and evaluated on the remaining 20%. YOLOv11 demonstrated superior performance, achieving 96.22% classification accuracy on BraTS2020 and 96.41% on Figshare, with an F1-score of 0.990, recall of 0.984, mAP@0.5 of 0.993, and mAP@ [0.5:0.95] of 0.801 during testing. With a fast inference time of 5.3 ms and a balanced precision–recall profile, YOLOv11 proves to be a robust, real-time solution for brain tumor detection in clinical applications.
Effects of a warm-up program on jump-landing pattern and lumbopelvic function in female basketball players with dynamic knee valgus
Abstract Dynamic knee valgus (DKV), commonly observed during functional movements, is recognized as a key biomechanical factor contributing to the risk of anterior cruciate ligament (ACL) injury. Given its importance in injury prevention, this study aimed to investigate the effects of a warm-up program on jump-landing pattern and lumbopelvic function in female basketball players exhibiting dynamic knee valgus. The present study employed a quasi-experimental design. Thirty female basketball players with DKV were screened using the single-leg landing (SLL) test and subsequently randomized into control (n = 15) and experimental (n = 15) groups. The jump-landing test was utilized to assess the jump-landing pattern, whereas the forward step-down (FSD) test was implemented to evaluate lumbopelvic function. The experimental group participated in the STOP-X warm-up program over 8 weeks, whereas the control group continued with their traditional warm-up routine. Data were analyzed using a 2 × 2 repeated measures ANOVA, followed by Bonferroni post hoc tests, with statistical significance set at P < 0.05. All analyses were conducted using SPSS version 26. The results revealed significant differences in maximum flexion (F = 20.73; P = 0.001; effect size (ES) = 0.42, percentage change (PC) = ↑4.48%), initial valgus (F = 90.12; P = 0.001; ES = 0.76, PC = ↓32.56%), maximum valgus (F = 151.6; P = 0.001; ES = 0.84, PC = ↓52.86%), and FSD (F = 22.82; P = 0.001; ES = 0.44, PC = ↓51.45%) in the experimental group compared to the control group after following the STOP-X warm-up program. However, no significant impact was observed for the initial flexion (P = 0.49, ES = 0.01) variable. Implementing the warm-up injury prevention program significantly improves jump-landing pattern and optimizes lumbopelvic function. Therefore, it is recommended that coaches incorporate this program in place of traditional basketball warm-up routines. Such an approach may enhance athletic performance while reducing the risk of knee injuries associated with improper landing techniques. Trial registration No: IRCT20231230060574N1, (date of registration on 04/01/2024) registered in the Iranian Registry of Clinical Trials.
Effect of doped wax on the rheological properties and chemical structure of ultraviolet aged bitumen
Development of porous COP–ceramic composites for application as low-relative-permittivity, low-dielectric-loss substrates in next-generation communication systems
3D-printed setup for ocular drug delivery evaluation on ex vivo porcine whole eye
Abstract Reaching the back of the eye without invasive intraocular injections is still nowadays challenging. Luckily, the nanotechnology can help in improving the effectiveness and the patient compliance and, ultimately, the therapeutic success rate. The development and characterization of ophthalmic (nano)formulations benefit from the implementation of ex vivo models, that allow to disclose the formulation behaviour once in contact with biological tissues and consequently its optimization. Ex vivo ocular models help to minimize the number of promising formulations deserving to be investigated in in vivo animal models, in compliance with the 3Rs principle, and therefore their availability is of paramount importance. In this research work, we present a 3D-printed reusable device designed to be used in a whole porcine eye bulbs setup comparing it with the Franz-cell. The device, produced by a Masked Stereolithography Apparatus, consists of two components, the Ocudonor, acting as a donor chamber for the formulation, and the Ocutainer, which simultaneously contains up to three ocular bulbs. The porcine eye setup was validated using a dexamethasone-loaded nanostructured lipid carriers for periocular administration and intended for the treatment of the posterior segment of the eye. The porcine whole eye model proved capable of preserving eye structure integrity for at least 18 hours and, unlike the Franz-cell, enabled the evaluation of the drug’s lateral diffusion along the eye bulb.