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The aim of this study was to comprehensively describe and compare the effects of different practice tasks, specifically 4 × 4, 3 × 3, 2 × 2 with goalkeepers (GK) in a 40 × 20 m field court. Forty-two male U17 players (age = 15.62 ± 0.58 years) from three futsal teams participated in the study. The tactical-technical offensive and defensive actions were measured using Videobserver® software. To measure external load (EL) and internal load (IL) during futsal tasks, the WIMU PROTM Ultra-Wideband (UWB) tracking system was used. To compare the tasks, the ANOVA for repeated measures was used. Results revealed that the reduction on the number of players contributed to increase the number of passing and shooting actions, while a generalised increase in physical and physiological responses were observed. In general, the major differences were observed between GK + 2 × 2 + GK and GK + 3 × 3 + GK in relation to GK + 4 × 4 + GK while some differences in physical and tactical-technical actions were also observed between GK + 2 × 2 + GK and GK + 3 × 3 + GK. Thus, the reduction on the number of players in large games can be considered a pedagogical strategy to promote an increase in the tactical-technical actions, such as passing and shooting actions, increasing the physical intensity of players. [ABSTRACT FROM AUTHOR]

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Logistics activities involve significant risk factors for the development of work-related musculoskeletal disorders (WMSD), particularly low back pain. Exoskeletons have emerged as potential solutions to mitigate these risks. This study assesses the short-term effects of dual passive back-support exoskeletons (Auxivo and Htrius) on WMSD risk factors in logistics operations. Two workstations were evaluated using self-report ratings, postural assessment, and surface electromyography (EMG). The results indicate that both exoskeletons provided relief and support during tasks, with Htrius showing a slight advantage. Exoskeletons reduced perceived exertion, especially during trunk flexion tasks, and improved posture, particularly in tasks involving manual lifting loads at lower height levels. While variations in muscular activity were observed, the Htrius exoskeleton showed a trend of reducing lumbar muscle activity. Overall, Htrius demonstrated promise in improving workers' comfort, safety, and efficiency, potentially reducing WMSD risk and muscular fatigue. However, individual preferences and workplace-specific characteristics should be considered when selecting exoskeleton models. Future research should explore the effects on different loads, genders, and EMG of different muscles to further enhance the understanding and application of exoskeletons in occupational contexts. [ABSTRACT FROM AUTHOR]

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Introduction: The aim of this study was to analyze the effects of space and number of players manipulation on the external and internal load demands of youth futsal athletes. Methods: Forty-two male U17 players (age = 15.62 ± 0.58 years) from three futsal teams participated in the study. In this cross-sectional study that lasted 8-week, the player's sample practiced six futsal tasks (T1-T6) and a futsal game played under the official rules (T7). From T1-T6, two task constraints were manipulated: (i) the number of players and, (ii) the space of play. The WIMU PROTM Ultra-Wideband (UWB) tracking system was used to measure the external and internal load during the futsal tasks. External load was quantified using kinematic and mechanical variables extracted from positional data and, the internal load was quantified using Heart rate (HR) and rating of perceived exertion (RPE). Repeated measures ANOVA was used for comparison purposes. Results: In general, the results showed high external (total distance, distance 18.1-21, above 21 Km/h, and high intensity acceleration and deceleration, p < 0.001) and internal load (heart rate average and rating of perceived exertion, p < 0.001) in the tasks with low number of players and high area. In relation to the match, the tasks with small relative area per player (GK + 2 vs. 2 + GK and GK + 3 vs. 3 + GK in 20 × 20 m) promoted low external load. Conclusion: It was concluded that increasing the relative area by reducing the number of players involved in the tasks in the form of small-sided games (GK + 2 vs. 2 + GK and GK + 3 vs. 3 + GK), in relation to the futsal game (GK + 4 vs. 4 + GK), can be considered a pedagogical strategy to increase the external and internal load demands of young futsal players. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to construct econometric models to identify and analyze the variables that define and explain the deforestation cycle in the Amazon. Theoretical framework: The forest is one of the main sources of carbon sequestration and storage on Earth. Thus, deforestation and forest burning contribute to increasing the impact of the greenhouse effect on climate change, due to CO2 emissions. The protection of the Amazon forest is prioritized for its contribution to mitigating the effects of climate change. Results and conclusion: The annual increase in deforested forest area in the Amazon follows a polynomial behavior explained by the exchange relationships between the prices of deforested and occupied areas with crops and pastures and the prices of lands with native forest. It is this exchange relationship that deserves the attention of policymakers for forest preservation through deforestation control. Research implications: This exchange relationship can cause a turnaround in the deforestation cycle based on the knowledge of the value of standing forests, a fact that would reverse the exchange relationship and require the adoption of sustainable practices in agricultural, livestock, mineral, and forestry production systems. Originality/value: This research shows that there is an increase in deforested area in the Amazon forest, with only the rate of this deforestation varying, which can be increasing or decreasing. Objetivo: Construir modelos econométricos para identificar e analisar as variáveis que definem e explicam o ciclo do desmatamento na Amazônia. Referencial teórico: A floresta é uma das principais fontes de sequestro e armazenamento de carbono da Terra. Logo o desmatamento e queima de florestas contribuem para aumentar o impacto do efeito estufa nas mudanças climáticas, em função das emissões de CO2. Resultados e conclusão: O incremento anual da área de floresta desmatada na Amazônia segue um comportamento polinomial explicado pelas relações de troca entre os preços das áreas desmatadas e ocupadas com lavouras e com pastagens e os preços das terras com floresta nativa. É essa relação de troca que merece a atenção dos formuladores de política para a preservação da floresta via controle do desmatamento. Implicações da pesquisa: Essa relação de troca pode causar uma reviravolta no ciclo do desmatamento a partir do conhecimento do valor da floresta em pé, fato que reverteria a relação de troca e exigiria a adoção de boas práticas sustentáveis nos sistemas de produção agrícola, pecuário, mineral e florestal. Originalidade/valor: A causa de maior impacto sobre o desmatamento é o desconhecimento do valor dos ativos naturais e do fluxo de serviços que ofertam à economia e aos seres humanos. Sem este conhecimento, o custo de oportunidade do estoque de terras com florestas na Amazônia, que supera o preço sombra das terras com lavouras, pastagens e manejo florestal, fixado por agentes econômicos em nível próximo a zero, equivalente a um fator de produção público em abundância. [ABSTRACT FROM AUTHOR]