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As turbinas hidráulicas são uma das principais componentes na geração da energia hidrelétrica, porém, o alto valor de aquisição e manutenção desses dispositivos constitui a maior limitação para uso nos países em via de desenvolvimento. É neste contexto que se realizou uma pesquisa experimental com objetivo de construir uma turbina hidráulica do tipo Francis, utilizando materiais alternativos, capaz de gerar energia elétrica para uso residencial. A turbina foi testada no laboratório de Física da Universidade Rovuma – Nampula e instalada num trecho do rio Muatala, na cidade de Nampula, gerando a potência hídrica de 147W e potência do eixo da turbina de 132W, que conectado a um gerador elétrico, registou-se uma tensão de 133V e corrente elétrica de 34mA. Os parâmetros elétricos obtidos podem ser usados no acionamento de eletrodomésticos de baixa potência. Conclui-se que a turbina hidráulica do tipo Francis construída a partir de materiais alternativos apresenta sustentabilidade social, ambiental e econômica para geração de eletricidade para uso residencial.

Background/Objectives : This study presents a novel approach, based on a combination of radiomic feature extraction, data resampling techniques, and machine learning algorithms, for the detection of degraded bone structures in Dual X-ray Absorptiometry (DXA) images. This comprehensive approach, which addresses the critical aspects of the problem, distinguishes this work from previous studies, improving the performance achieved by the most similar studies. The primary aim is to provide clinicians with an accessible tool for quality bone assessment, which is currently limited. Methods : A dataset of 1531 spine DXA images was automatically segmented and labelled based on Trabecular Bone Score (TBS) values. Radiomic features were extracted using Pyradiomics, and various resampling techniques were employed to address class imbalance. Three machine learning classifiers (Logistic Regression, Support Vector Machine (SVM), and XGBoost) were trained and evaluated using standard performance metrics. Results : The SVM classifier outperformed the other classifiers. The highest F-score of 97.5% was achieved using the Grey Level Dependence Matrix and Grey Level Run Length Matrix feature combination with SMOTEENN resampling, which proved to be the most effective resampling technique, while the undersampling method yielded the lowest performance. Conclusions : This research demonstrates the potential of radiomic texture features, resampling techniques, and machine learning methods for classifying DXA images into healthy or degraded bone structures, which potentially leads to improved clinical diagnosis and treatment.

Data on long-term treatment regimens for preventing bone mineral density (BMD) loss that occurs after denosumab (Dmab) withdrawal are scarce. Our aim was to evaluate the long-term changes (12-36 months) in BMD and bone turnover markers in a group of postmenopausal women who had been treated with Dmab and received subsequent treatment with bisphosphonates. Secondary objectives were to evaluate factors associated with BMD loss, to compare the BMD change in patients who received oral vs intravenous bisphosphonates, and to assess the frequency of fragility fractures after Dmab discontinuation. The clinical data of 54 patients, 26 of whom had clinical and DXA assessments at 36 months, were analyzed. After 12 months, the mean LS BMD had decreased by 2.8% (±5.0), FN BMD by 1.9% (±5.8), and TH BMD by 1.9% (±3.7). After 36 months, LS BMD had decreased by 3.7% (±6.7), FN BMD by 2.5% (±7.1), and TH BMD by 3.6% (±5.2). C-terminal cross-linked telopeptide of type I collagen significantly increased during the first 12 months after Dmab withdrawal but then decreased at 36 months. BMD loss at 12 months was higher in patients with more than 30 months of Dmab treatment, but this difference was only statistically significant at FN (-3.3% vs -0.3%, P  = .252 at LS, -3.3% vs 0.3%, P  = .033 at FN, and -2.1% vs 0.9, P  = .091 at TH). There were no statistically significant differences regarding the change in BMD at 12 and 36 months between oral and intravenous treatment. Seven patients suffered incidental vertebral fractures (clinical vertebral fractures: n  = 6, morphometric fractures: n  = 1) three of which were multiple. None of these patients were treated following international or institutional guidelines or recommendations. In summary, our study suggests that bisphosphonates can help maintain BMD for 36 months after Dmab discontinuation., Competing Interests: M.B.Z. had received speaker honoraria from Amgen. The other authors declare no potential conflicts of interest regarding this work., (© The Author(s) 2024. Published by Oxford University Press on behalf of the American Society for Bone and Mineral Research.)

Objectives: Sarcopenia is the loss of skeletal muscle mass and function that occurs with aging that can lead to greater morbidity and mortality. Chronic kidney disease and hemodialysis (HD) favors the development of sarcopenia. We studied the prevalence of sarcopenia and its components using European Working Group on Sarcopenia in Elderly People 2 proposed criteria and risk factors for its development in HD patients., Methods: In 100 adult HD patients, we evaluated: hand grip strength (HGS), muscle mass by dual energy X-ray absorptiometry and physical performance (gait-speed and sit-stand test)., Results: Sixty patients were male and 40 were female; mean age 55.6 years. Prevalence of sarcopenia was 16% (11.1% in males and 25% in females; P = 0.05); 7% had severe sarcopenia. Prevalence of low HGS was 33% in males and 28% in females; low muscle mass was 30% in males but 70% in females and low physical performance 23% in males and 45% in females. Falls were reported by 23 patients. Patients with lower HGS had a higher prevalence of falls in the last year (40% two or more falls; P = 0.03). Only females with sarcopenia had lower bone mineral content. Neither age, body mass index, time on dialysis, or prevalence of diabetes predicted sarcopenia., Conclusions: A significant proportion of dialysis patients had sarcopenia, more frequent in females. Low HGS was associated with a higher prevalence of falls. Only females with sarcopenia had lower bone mineral content., Competing Interests: The authors declare no competing interests., (© 2021 The Korean Society of Osteoporosis. Publishing services by Elsevier B.V.)

The traditional ethnobotanic and pharmacologic use of Spondias mombin L. samples includes a wide range of applications. In the present study, new antiangiogenic and antitumor effects of two types of extracts from Spondias mombin L. leaves have been demonstrated by using a number of in vitro assays in both endothelial and human cancer and non cancer cells., (Copyright © 2020 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: Magnetic resonance imaging is considered a preferable imaging examination in the diagnosis of inflammatory maxillary sinus disease and can provide precise sinonasal characterization. Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient are complementary magnetic resonance imaging tools that can be applied to the differentiation of sinus diseases. In this report, 3 cases of inflammatory maxillary sinus diseases imaging findings considering diffusion-weighted magnetic resonance imaging features were described. Additionally, a literature review considering the use of diffusion-weighted magnetic resonance imaging in inflammatory lesions is provided., Methods: The cases reported were: presence of air-fluid levels, mucosal thickening and a mucous retention cyst. Conventional magnetic resonance imaging and apparent diffusion coefficient (ADC) maps, with ADC values were demonstrated. In the literature review, the studies considering inflammatory lesions were detailed, as well as ADC values established by investigators., Results: ADC values for presence of air-fluid levels, mucosal thickening and mucous retention cyst were respectively: 1.99 x 10 -3 mm 2 /s; 1.83 x 10 -3 mm 2 /s; 2.05 x 10 -3 mm 2 /s., Conclusions: It was observed that apparent diffusion coefficient values from the inflammatory lesions described in this report were different and apparent diffusion coefficient may be useful in the differentiation of these maxillary sinus alterations. Further larger sample investigations considering apparent diffusion coefficient values focusing in inflammatory lesions are recommended. The lack of studies considering the use of diffusion-weighted magnetic resonance imaging on inflammatory diseases diagnostic was the major limitation to the literature review.