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In the last few years, offshore wind power has experienced remarkable growth attributable to the need to mitigate the impact of global warming, which leads to policies for reducing greenhouse gas emissions and fostering investment in renewable technologies. However, this endeavor raises concerns regarding economic assessment studies, where the levelized cost of energy (LCOE) is the most widely adopted index. This paper aims to propose an estimation of the LCOE under generation uncertainty induced by the intermittency of the wind and thus determine how the LCOE obtained by a deterministic approach is affected. To carry out this task, we employ two techniques based on stochastic differential equations to generate wind power scenarios. Utilizing 40 years of recorded wind speed data sourced from the MERRA-2 reanalysis, we derive the input parameters of the models from fitting to 4-parameter Dagum and Johnson SB probability distributions, which shows that accurate modeling of offshore wind speeds requires dealing with complex mathematical functions that need numerical computation. The findings show that the stochastic approach can estimate an uncertainty interval around the result obtained via the deterministic approach. In the case studies examined, the maximum and minimum values correspond to approximately ±1.6% and ±3.5% from the deterministic LCOE.
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The Guadeloupe archipelago, situated in the eastern Caribbean Sea with a population of approximately 400,000 inhabitants, faces distinctive challenges in realizing a sustainable and resilient energy transition owing to its nature being a distributed island system. These unique challenges include the absence of energy interconnections, limited domestic energy resources, substantial dependence on fossil fuels, and considerable load variance. These factors necessitate specialized attention in the study and analysis of the energy system transition. In this study, the authors initially delineate storylines tailored to the specific requirements of Guadeloupe's energy system, with a primary focus on the reliance on fossil fuel imports. Two distinct energy transition roads, aiming for self-sufficiency and independence for Guadeloupe by 2040 and 2050, are established. Leveraging an advanced open-source investment and dispatch tool, the Global Energy System Model (GENeSYS-MOD), these storylines are implemented to ascertain the least-cost, sustainable, and resilient energy transition for the Guadeloupe archipelago. The ensuing results are comprehensively analyzed to offer insights into Guadeloupe's trajectory towards a sustainable energy system, comparing the proposed energy transition roads for achieving sustainability. The findings reveal that substantial investments in wind and photovoltaic power plants, coupled with electricity storage devices, are imperative for achieving energy independence in the future. Additionally, the availability of biomass emerges as a crucial factor facilitating a seamless transition across all sectors, encompassing power, heat, and transportation.
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To the best of our knowledge, this work represents the first report in the literature on the implementation of a radio- and power-over-fiber (RPoF) system utilizing double-clad fiber (DCF) aimed at the sixth generation of mobile communications networks (6G) operating in millimeter-waves (mm-waves). The deployed FiWi (fiber/wireless) system makes use of the DCF core and first cladding for simultaneously and optically transmitting data and power using the same fiber-optics link. For the first time, we demonstrate the simultaneous transmission of a broadband 26-GHz 5G New Radio (NR) signal in conjunction with 20 W of optical power through a 250-m DCF link. Such achievement represents a 150% reach enhancement, compared to the current commercial-available femtocells from the fourth and fifth generations of mobile communications networks (4G and 5G), which use Power-over-Ethernet (PoE) interfaces that typically provide 1 Gbps throughput limited to 100 m reach. The PoF key components of the remote antenna unit (RAU), such as the photodetector and RF amplifier, are optically powered by using PoF technology. We evaluate the PoF system efficiency and stability over extended periods and compare the analog RoF (A-RoF) system performance, by means of conventionally versus optically powered. Experimental results indicate the proposed RPoF system meets the 3rd Generation Partnership Project (3GPP) requirements, in terms of the root mean square error vector magnitude (EVMRMS), with no impairments. Overall, our FiWi system demonstrator provides a throughput of 1.6 Gbps using 16-quadrature amplitude modulation (QAM) over 5-m wireless transmission in the mm-waves band. The obtained experimental data highlight the feasibility of integrating optical and wireless technologies for supporting more reliable and scalable beyond 5G (B5G) and 6G systems.
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Objective: To analyze the influence of lower limb muscle strength and muscle power training on rate of force development (RFD) and peak force (PF) in elderly people with Parkinson's disease (PD), as well as the effect of these training sessions influence on the functional mobility (FM) of this population. Methods: This was a randomized controlled clinical trial and registered on the virtual platform for registration of experimental and non-experimental studies "Registro Brasileiro de Ensaios Clínicos (ReBEC)". Thirty four elderly people of both genders without and with PD were divided into four groups: strength training control (GSC, n = 8); potency training control (GPC), n = 9; subjects with PD submitted to strength training (GSPD, n = 8); subjects with PD submitted to potency training (GPPD, n = 9). GSC and GPC consisted of with no history of neurological diseases. PF and RFD in the first 50 and 200 milliseconds (ms) were determined. FM was also assessed using the following tests: gait speed test (GS), Timed Up and Go (TUG), Short Physical Performance Battery (SPPB), Unified Parkinson's Disease Rating Scale (UPDRS); parallel feet on a force platform. Next, the participants underwent lower limbs muscle strength or muscle power training for eight consecutive weeks twice a week and were then re-evaluated. Results: The repeated measures ANOVA test showed a significant difference for PF, RFD and FM regardless of training type. Conclusion: The proposed muscle strength and muscle power training protocols influenced the increase in RFD, PF and FM of all participants; however, the increase in RFD in the first 200 ms was more pronounced in the groups submitted to power training and the increase in PF was more pronounced in the groups submitted to strength training.
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Survival models with cure fractions, known as long-term survival models, are widely used in epidemiology to account for both immune and susceptible patients regarding a failure event. In such studies, it is also necessary to estimate unobservable heterogeneity caused by unmeasured prognostic factors. Moreover, the hazard function may exhibit a non-monotonic shape, specifically, an unimodal hazard function. In this article, we propose a long-term survival model based on a defective version of the Dagum distribution, incorporating a power variance function frailty term to account for unobservable heterogeneity. This model accommodates survival data with cure fractions and non-monotonic hazard functions. The distribution is reparameterized in terms of the cure fraction, with covariates linked via a logit link, allowing for direct interpretation of covariate effects on the cure fraction-an uncommon feature in defective approaches. We present maximum likelihood estimation for model parameters, assess performance through Monte Carlo simulations, and illustrate the model's applicability using two health-related datasets: severe COVID-19 in pregnant and postpartum women and patients with malignant skin neoplasms.
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Many hormones, including estrogens, modulate bone metabolism, which plays a crucial role in maintaining bone health. Estrogen depletion, as occurs in menopause, leads to increased bone resorption and decreased formation, resulting in osteopenia/osteoporosis. This study investigates the effects of flaxseed (Linum usitatissimum) and mulberry (Morus nigra L.) extracts, known for their phenolic compounds and antioxidant properties, against estrogen deficiency-induced bone loss in female Wistar rats. These extracts were administered to ovariectomized rats for 60 days. High-performance liquid chromatography analysis revealed the presence of some phenolic compounds in the extracts, including trigonelline, gallic acid, theobromine, chlorogenic acid, syringic acid and p-coumaric acid. The extracts improved bone microstructure with higher trabecular bone, bone mineral density, calcium, phosphorus and magnesium levels, and lower porosity and intertrabecular space in bone tissue. Furthermore, plasma alkaline phosphatase activity was elevated in extract-treated animals, indicating enhanced bone tissue formation. Although serum carboxy-terminal fragment levels showed no significant change, the data suggest that flaxseed and mulberry extracts may protect against trabecular bone loss and support bone formation in estrogen-deficient conditions. These results suggest that supplementing these natural extracts holds promise in preventing or alleviating the signs and symptoms associated with estrogenic deficiency.
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Extraction of bioactive compounds from vegetal matrices is a dynamic field in pharmaceutical, cosmetic and food industry. Many of these compounds have high medicinal value. Ultrasonic assisted extraction (UAE) becomes an interesting alternative to reduce both the amount of chemical solvents and the processing time. The aim of the present paper is to introduce, intuitively, the physical mechanisms involved in ultrasonic extraction for non-specialists. Two different mechanisms, cavitation and acoustic streaming, can be easily experimentally shown. The proposed experiment is the extraction of the sugar cover in sugar-coated chocolates. Extraction is analyzed using video tools to obtain a quantitative evolution of the process. Graphical results and videos are a useful tool for showing the basis of ultrasonic extraction in several levels from primary school to university students. In the event that the necessary ultrasound equipment is not available, we hope that the videos available in the supplementary material will be useful for teaching the topic.
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Fracionamento Químico , Fracionamento Químico/métodos , Ondas Ultrassônicas , Açúcares/química , Carboidratos/químicaRESUMO
BACKGROUND AND PURPOSE: Children with myopathies often experience muscle weakness in their lower limbs. However, the upper limbs are also affected and, at the same time, play a key role in daily living activities as well as in transfers and assisted mobility using auxiliary devices. The objective was to assess the performance of the elbow flexor and extensor muscles through static and dynamic contractions in children with myopathies and in their typical peers. METHODS: This was a case-control study. Seven children with different myopathies participated and were matched with typical children by sex and age (1:2). The muscle performance of elbow flexors (EFL) and elbow extensors (EEX) was assessed using an isokinetic dynamometer using isometric and isokinetic contractions at a speed of 120°s-1. The analyzed variables were peak torque (PT), total work (W), power (P), time to peak torque (TPT), acceleration time (AT), and deceleration time (DT). The raw variables were compared between groups using linear regression with mixed effects. A significance level of p < 0.05 was adopted. RESULTS AND DISCUSSION: Children with myopathies showed significantly lower values of PT, W, and P for both elbow muscle groups (p < 0.05) compared to typically developing children; TPT showed no difference between groups; and AT and DT were higher in children with myopathies than in typical ones (p < 0.05). Children with myopathies exhibited deficits in muscle performance, suggesting that the elbow muscles adopt atypical motor strategies, indicating impaired neuromuscular control. The isokinetic dynamometer is a device that can provide relevant information about muscle performance in this group of diseases.
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Força Muscular , Músculo Esquelético , Humanos , Estudos de Casos e Controles , Criança , Masculino , Feminino , Músculo Esquelético/fisiopatologia , Músculo Esquelético/fisiologia , Força Muscular/fisiologia , Doenças Musculares/fisiopatologia , Torque , Dinamômetro de Força Muscular , Cotovelo/fisiopatologia , Adolescente , Articulação do Cotovelo/fisiopatologia , Articulação do Cotovelo/fisiologia , Contração Isométrica/fisiologia , Contração Muscular/fisiologiaRESUMO
The archipelago of Puerto Rico has faced multiple natural disasters, including hurricanes and earthquakes, disrupting the mental health and daily lives of its residents. These disasters, combined with socio-political abandonment, have led to the deterioration of the electrical grid, exacerbating health disparities. This study aimed to explore the linkages between natural and structural disasters, mental health, and energy independence in Puerto Rico. In this setting, the community organization Casa Pueblo has installed solar panels in the homes of people with chronic health conditions. Through ethnographic fieldwork in the town of Adjuntas and qualitative interviews with 45 individuals with different levels of access to solar power, we explore the implications of ongoing natural and structural disasters on the mental health of individuals and how access to solar energy could help mitigate their effects. Results indicate that participants with direct and indirect access to solar panels held positive and hopeful narratives regarding their mental well-being and quality of life. This innovative model of communal energy security through solar power for climate adaptation holds promises for enhancing mental health in the town of Adjuntas and potentially in other regions.
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Saúde Mental , Humanos , Feminino , Masculino , Porto Rico , Pessoa de Meia-Idade , Energia Solar , Desastres , Qualidade de Vida , Idoso , Adulto , Pesquisa Qualitativa , Entrevistas como Assunto , Antropologia CulturalRESUMO
In this article, we aim to evaluate the effects of photobiomodulation on mitochondria quantity, biogenesis, and mitophagy-associated genes in breast cancer (BC) cells. Both models were irradiated with a low-power infrared laser (880 nm, 150 mW) and amber LED (617 nm, 1500 mW), alone or simultaneously. We evaluated the mRNA expression of PINK1 and PGC-1α genes, and the mitochondrial number was assessed based on the ratio of mitochondrial DNA/genomic DNA (mtDNA/gDNA). No significant difference was observed in the mtDNA/gDNA ratio comparing the low-power infrared laser (LPIL) and LED-irradiated groups to their control counterparts. Similarly, no difference was observed in the mRNA levels of PINK1 and PGC-1α of the irradiated group with an LPIL and LED alone or in combination. In conclusion, PBM with LPIL and LED did not alter the mtDNA/gDNA ratio nor modulate the mRNA levels of the genes related to mitophagy and biogenesis in BC cells.
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Neoplasias da Mama , DNA Mitocondrial , Terapia com Luz de Baixa Intensidade , Mitocôndrias , Mitofagia , Humanos , Mitofagia/efeitos da radiação , Mitofagia/genética , Neoplasias da Mama/radioterapia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Terapia com Luz de Baixa Intensidade/métodos , Feminino , Mitocôndrias/efeitos da radiação , Mitocôndrias/genética , Mitocôndrias/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/efeitos da radiação , Linhagem Celular Tumoral , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismoRESUMO
BACKGROUND: Photobiomodulation therapy (PBMT) has recently been indicated as a potential therapeutic strategy in diverse health and sports contexts. However, its efficacy on muscle performance in female futsal players remains unknown. The purpose of this study was to investigate the dose-response effect of PBMT on muscle performance in female futsal players. METHODS: In a crossover design, fifteen female futsal athletes (age: 18-30 years) were randomized to receive 1 of 4 PBMT conditions (placebo, 300, 900, and 1260 J [J]) on four occasions, separated by a 2-wk washout period. PBMT treatments were applied on the quadriceps muscle of both legs using a device containing 200 light-emitting diodes (LEDs), immediately before the following tests: countermovement jump (CMJ) (i.e., flight time as indicator of muscle power), maximum voluntary isometric contraction (MVIC) for the leg extension exercise (i.e., muscle strength), and 3 sets of repetitions-to-failure (i.e., local muscular endurance) for the 45° leg press exercise, with recording of rating of perceived exertion (RPE) after each set. The fatigue index was determined by the number of repetitions between sets 1 and 3. RESULTS: No significant differences were found between the PBMT conditions for the maximum number of repetitions (p = 0.899), RPE (time p < 0.0001; interaction p = 0.653), fatigue index (p = 0.835), muscle power (p = 0.789), and isometric peak and mean torque (p = 0.776 and 0.537, respectively). CONCLUSION: Different doses of acute PBMT with LEDs do not improve muscle performance (endurance, power, and strength) and RPE in female futsal players.
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Estudos Cross-Over , Terapia com Luz de Baixa Intensidade , Força Muscular , Músculo Quadríceps , Humanos , Feminino , Terapia com Luz de Baixa Intensidade/métodos , Adulto Jovem , Adulto , Força Muscular/fisiologia , Método Duplo-Cego , Adolescente , Músculo Quadríceps/fisiologia , Contração Isométrica/fisiologia , Futebol/fisiologia , Fadiga Muscular/fisiologiaRESUMO
BACKGROUND: Physical fitness has been considered an important health indicator. Several factors can impact the increase in physical fitness in children and adolescents, including chronological age, sex and BMI, in addition to training variables such as weekly frequency, session and intervention duration, and types of exercises performed. To know the importance of variables that can impact physical fitness, it is important for health professionals to identify the most efficient way of prescribing physical exercises for children and adolescents. The aim is review and meta-analyses of the effects of supervised and structured physical exercise on the physical fitness trainability of children and adolescents. METHODS: Relevant articles were searched in the PubMed, Cochrane Library, Embase and Scopus platform databases and selected based on the following criteria: children and adolescents aged between 7 and 17 years who performed any type of structured physical exercise compared to a control group without exercise and evaluating physical fitness (strength or muscular power, cardiorespiratory fitness (CRF) or speed. The results are reported in accordance with PRISMA 2020. RESULTS: Eighty studies were included with a total of 5769 participants. Strength exercises (ES: 1.073; 95% CI, 0.612-1.533; P < 0.001; I2: 74%), concurrent (ES: 1.054; 95% CI, 0.255-1.853; P < 0.010; I2: 72%) and sports (ES: 0.573; 95% CI, 0.015 to 1.132; P < 0.044; I2: 34%) seem to be the most effective in increasing muscular strength. Aerobic activities (ES: 0.400; 95% CI, 0.258-0.542; P < 0.001; I2: 74%), sports (ES: 0.271; 95% IC, 0.148-0.394; P < 0.001; I2: 15), or HIIT (ES: 0.668; 95% IC, 0.333-1.003; P < 0.001; I2: 29%) resulted in increased CRF (ES: 0.514; 95% IC, 0.220-1.808; P < 0.001; I2: 66%). The practice of physical exercise increased muscular power (ES: 0.241; 95% CI, 0.053-0.429; P = 0.012; I2: 0%). The practice of HIIT impacts MAS gains (ES: 0.048; 95% CI, 0.050 - 0.026; P = 0.029; I2: 44%). CONCLUSION: Supervised and structured physical exercise can improve muscular strength (15-35%), CRF (5.4-8.5%), muscular power (5.6-11.8%), and MAS (5.4%) trainability in children and adolescents. Sex, BMI of the subjects and type of exercise performed (aerobic activities, exclusive to strength, HIIT or sports) should be considered when prescribing the exercise.
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Aptidão Física , Humanos , Adolescente , Criança , Força Muscular , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologiaRESUMO
Musculoskeletal pain (MSP) remains one of the leading causes of disability worldwide. Recent approaches to treating this condition have prompted the development of several systematic reviews investigating the efficacy of high-intensity laser therapy (HILT), whose analgesic mechanisms are based on photobiomodulation neural inhibition, endorphin and serotonin release and anti-inflammatory effects. To assess the methodological quality, reliability, and validity of the systematic reviews (SRs) on HILT in MSP. This study is an overview of SRs (umbrella review) with an observational, retrospective, and secondary design. The search considered PubMed, Scopus, Web of Science, CINAHL, Embase, Cochrane Library, ScienceDirect, and Google Scholar databases (updated October 23, 2024). The primary focus was on the methodological quality of the reviews and their reporting of pain intensity results. The HILT effects on pain intensity were reported using mean differences (MD) or standardized mean differences (SMD). The quality assessment was conducted using the A Measurement Instrument to Assess Systematic Reviews 2 checklist (AMSTAR-2), and the findings were synthesized narratively. The MD and SMD obtained from all reviews were presented using forest plots. The Shapiro-Wilk normality test assessed MD and SMD distributions for pain intensity across meta-analyses. The average MD and SMD, along with their respective confidence intervals (CI), were estimated and presented based on the aggregate study outcomes. Twenty SRs were included, fourteen of which conducted meta-analyses covering diverse musculoskeletal disorders such as knee osteoarthritis, epicondylalgia, myofascial pain, frozen shoulder, plantar fasciitis, neck, and low back pain. The primary databases used were PubMed, Web of Science, and the Cochrane Library. The AMSTAR-2 average score was 12.9 points (± 1.8), indicating varying methodological quality with one or two criteria resulting in low or critically low. HILT's best analgesic effects are observed in frozen shoulder disorder (MD = -2.23 cm; 95% CI:-3.3,-1.2; p < 0.01), knee osteoarthritis (MD = -1.9 cm; 95% CI:-2.0,-1.8;p < 0.01), low back pain (MD = -1.9 cm; 95% CI = -2.9,-1.0; p < 0.01), and myofascial pain (MD = -1.9 cm; 95% CI:-2.6,-1.2; p < 0.01). Largest effect sizes are for neck pain (SMD = 2.1; 95% CI = 1.2,3.0, p < 0.05) and low back pain (SMD = 1.1 (95% CI = 1.4,0.8; p < 0.01). This review underscores the generally low to critically low methodological quality of SRs on HILT, as assessed by AMSTAR-2. Key areas for improvement for future SRs of RCTs include addressing publication bias, disclosing funding sources, and enhancing search strategies and discussions on heterogeneity. The scarcity of RCTs for conditions such as temporomandibular disorders, carpal tunnel syndrome, and myofascial pain highlights the need for further research. SRs on spinal disorders, frozen shoulder, and neck pain demonstrated the most favorable analgesic effects, providing valuable insights for clinical practice and future RCTs.
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Terapia a Laser , Dor Musculoesquelética , Manejo da Dor , Revisões Sistemáticas como Assunto , Humanos , Terapia a Laser/métodos , Dor Musculoesquelética/radioterapia , Manejo da Dor/métodos , Revisões Sistemáticas como Assunto/normasRESUMO
Instabilities in energy supply caused by equipment failures, particularly in power transformers, can significantly impact efficiency and lead to shutdowns, which can affect the population. To address this, researchers have developed fault diagnosis strategies for oil-immersed power transformers using dissolved gas analysis (DGA) to enhance reliability and environmental responsibility. However, the fault diagnosis of oil-immersed power transformers has not been exhaustively investigated. There are gaps related to real scenarios with imbalanced datasets, such as the reliability and robustness of fault diagnosis modules. Strategies with more robust models increase the overall performance of the entire system. To address this issue, we propose a novel approach based on Kolmogorov-Arnold Network (KAN) for the fault diagnosis of power transformers. Our work is the first to employ a dedicated KAN in an imbalanced data real-world scenario, named KANDiag, while also applying the synthetic minority based on probabilistic distribution (SyMProD) technique for balancing the data in the fault diagnosis. Our findings reveal that this pioneering employment of KANDiag achieved the minimal value of Hamming loss-0.0323-which minimized the classification error, guaranteeing enhanced reliability for the whole system. This ground-breaking implementation of KANDiag achieved the highest value of weighted average F1-Score-96.8455%-ensuring the solidity of the approach in the real imbalanced data scenario. In addition, KANDiag gave the highest value for accuracy-96.7728%-demonstrating the robustness of the entire system. Some key outcomes revealed gains of 68.61 percentage points for KANDiag in the fault diagnosis. These advancements emphasize the efficiency and robustness of the proposed system.
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Dual-chamber microbial fuel cells (DC-MFC) are devices that can be used to generate electricity through the degradation of substrates. In this study, the performance of DC-MFC with novel electrode materials is evaluated under different external resistance using a hydrochloric acid solution as catholyte. Hydrophilic-treated graphene was used as the electrode material, DuPontTM Nafion 117 was used as the proton exchange membrane and domestic wastewater served as the substrate. The maximum power density achieved was 32.05 m W â m - 2 , obtained by degrading 69.8% of organic matter when an external resistance of 100 Ω was used as electrical load. This power density was 32 times higher than the power density obtained in the control (1.01 m W â m - 2 ). This result obtained was similar to those reported in the literature for small-scale DC-MFC systems. And, contrary to the reported trend that as the scale of MFCs increase, the efficiency decreases. It can be stipulated with these results that is possible to scale up DC-MFC to medium-scale systems without loss performance quality by selecting the appropriate external resistance, catholyte and electrode materials.
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Proper monitoring of rotating machines is responsible for the efficiency in detecting, diagnosing, or even prognosing failures. Effective monitoring can lead to increased economic viability of any equipment, as it may reduce costly repairs, decrease downtime, and increase safety. Knowing the behaviour of a machine promotes better monitoring of its operation and maintenance. Data-driven algorithms have been widely used to identify failures and predict the behaviour of machines and systems. The difficulty in obtaining reliable data to test strategies or methods for this purpose is well known. Our contribution is a set of electrical current data (time series data) from a rotating machine that generates electrical energy, generically called a power generator, in a laboratory. In this machine we have the possibility of, besides monitoring its healthy behaviour, causing internal defects that can reduce its efficiency and remaining useful life. We highlight three key lines of study with the data available here: it is possible to apply data processing tools to make discoveries not evidenced in studies; test and compare new data-driven algorithms using public and reliable data; engineering lectures can use the dataset regarding the study of electrical machines and data driving methods. The dataset contains information mainly about the voltage and current of generators when they are subject to internal faults. These faults include short circuits between turns of winding, short circuits between windings of the same phase, and short circuits between different phases. This dataset has a wide variety of bench configurations. The dataset comes from real generators and allows the study of phenomena that are difficult to reproduce through analytical or computational models. The time series of electrical currents are raw, no preprocessing has been done. In fact, the signals contain natural noise from an industrial environment. In this context, the main contribution of this work is to provide a public and reliable database, which helps to speed up the development of more efficient techniques for monitoring, diagnosis, and prognostics of the behaviour of rotating electrical machines.
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OBJECTIVE: The purpose of this investigation was to evaluate the acute effects of a systemic acupuncture protocol on strength and power performance of male handball players. INTRODUCTION: Regarding sports performance, different strategies have been used displaying different outcomes. In a more holistic approach, the use of manual therapies such as acupuncture has gained increased attention. METHODS: A convenience sample of 27 handball players divided into three distinct groups was used for analysis (Sham = 22.3 ± 3.77; Acupuncture = 23.6 ± 5.27; Control = 25.25 ± 5.50 years old). Participants were assessed for lower limb power (countermovement jump), handgrip strength, and maximal isometric voluntary contraction (MIVC) "pre" and "post" an acupuncture, control or Sham protocol. RESULTS: There were no statistically significant differences between groups regarding vertical jump performance. A significant reduction on MIVC was observed for the "Sham" group in the intraprotocol analysis for both dominant and non-dominant limbs (0.047). It was also found a significant reduction on handgrip strength in the intraprotocol comparison of both "Sham" (p = 0.028) and "acupuncture" (p = 0.015) groups. CONCLUSIONS: The use of an acute systemic acupuncture protocol provided a minor negative impact on handgrip strength performance in a sample composed of male handball players.
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Terapia por Acupuntura , Desempenho Atlético , Força da Mão , Contração Isométrica , Humanos , Masculino , Terapia por Acupuntura/métodos , Adulto Jovem , Adulto , Força da Mão/fisiologia , Desempenho Atlético/fisiologia , Método Duplo-Cego , Contração Isométrica/fisiologia , Força Muscular/fisiologia , Esportes/fisiologiaRESUMO
This paper presents a methodology for integrating Deep Reinforcement Learning (DRL) using a Deep-Q-Network (DQN) agent into real-time experiments to achieve the Global Maximum Power Point (GMPP) of Photovoltaic (PV) systems under various environmental conditions. Conventional methods, such as the Perturb and Observe (P&O) algorithm, often become stuck at the Local Maximum Power Point (LMPP) and fail to reach the GMPP under Partial Shading Conditions (PSC). The main contribution of this work is the experimental validation of the DQN agent's implementation in a synchronous DC-DC Buck converter (step-down converter) un-der both uniform and PSC conditions. Additionally, we establish a testing pipeline for DRL models. The DQN agent's performance is evaluated alongside the P&O algorithm. Results consistently indicate the DQN agent's superiority over the P&O algorithm in all simulated scenarios. Although this trend does not entirely replicate in real-world test setups, significant results are observed. Specifically, in PSC sce-narios where the P&O algorithm becomes trapped at an LMPP, the DQN algorithm extracts up to 63.5 % more power than the P&O algorithm. An open repository is available, containing PCB schematic designs and layouts, along with the code used for model training and deployment.
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The Republic of Ecuador is developing a comprehensive plan to meet the increasing residential, industrial, and commercial energy demands. With a population of 17.08 million in 2018, the country is experiencing an annual average energy growth of approximately 7.13% until 2027. This research aims to model the incorporation of new and proposed power plants strategically planned to cater to the expanding demand needs. Ensuring that our existing energy infrastructure can adequately meet the current and growing needs of the residential, commercial, and industrial sectors should be made possible. In this paper, we present several hypotheses that need to be made to identify the potential demands for residential, industrial, and commercial requirements, making it more accessible to build new facilities that use renewable energy. Traditional and unconventional renewable energy sources, such as hydro-power, wind, and solar power, are being explored to generate electricity. The research employs quantitative methodology, beginning with gathering information and a detailed data analysis. Subsequently, a scenario-based model will examine the impact on energy demand and supply from 2020 to 2035. The results show that the Santiago hydroelectric project is becoming essential for the country's energy development and that the current national power system will only be able to supply the electricity demand when the industrial city of Posorja is being developed. We suggest that to maintain Ecuador's electricity trade balance as an electricity exporter, we continue with the energy investment plans currently issued by the Ministry of Energy and Mines. This study is relevant for establishing global financing arrangements involving the public and private sectors. In doing so, we can meet our hypothetical scenarios, ensuring that all energy needs are met by 2035. This will involve developing a robust national grid system with sufficient reserve capacity, meeting residential and projected commercial and industrial demand.
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Centrais Elétricas , Equador , Carbono , Eletricidade , Energia RenovávelRESUMO
Cancer cells have the ability to undergo an unlimited number of cell divisions, which gives them immortality. Thus, the cancer cell can extend the length of its telomeres, allowing these cells to divide unlimitedly and avoid entering the state of senescence or cellular apoptosis. One of the main effects of photobiomodulation (PBM) is the increase in the production of adenosine triphosphate (ATP) and free radicals, mainly reactive oxygen species (ROS). Existent data indicates that high levels of ROS can cause shortening and dysfunctional telomeres. Therefore, a better understanding of the effects induced by PBM on cancer cell telomere maintenance is needed. This work aimed to evaluate the effects of low-power red laser (658 nm) and blue LED (470 nm) on the TRF1 and TRF2 mRNA levels and telomere length in human breast cancer cells. MCF-7 and MDA-MB-231 cells were irradiated with a low-power red laser (69 J cm-2, 0.77 W/cm-2) and blue LED (482 J cm-2, 5.35 W/cm-2), alone or in combination, and the relative mRNA levels of the genes and telomere length were assessed by quantitative reverse transcription polymerase chain reaction. The results suggested that exposure to certain red laser and blue LED fluences decreased the TRF1 and TRF2 mRNA levels in both human breast cancer cells. Telomere length was increased in MCF-7 cells after exposure to red laser and blue LED. However, telomere length in MDA-MB-231 was shortened after exposure to red laser and blue LED at fluences evaluated. Our research suggests that photobiomodulation induced by red laser and low-power blue LED could alter telomere maintenance and length.