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Análise do movimento do saque no tênis de campo por meio de processamento de imagem - diagnóstico visando à melhoria de desempenho
(Universidade Federal de São Carlos, 2021-07-24) Valim, Bruno; Montagnoli, Arlindo Neto; https://lattes.cnpq.br/2903750902988624; https://lattes.cnpq.br/0599043251342979
The present work consists in evaluating the movement of the serve in tennis, through video image processing using the Cinemetria software to render an 3D avatar. The software in C++ programming with specific algorithms for biomechanical analysis of movement, and it proposes to process the data automatically and correlate the kinematics with a specific protocol to measure and quantify key joint points in the human body, perform image acquisition without specific markers in the game scenario itself in such a way that the player can move without interference from special equipment. In addition to image processing, the goal is to identify the mechanical failure and diagnose the movement of the serve with the ball in real game time. The computer visualization structuring the motor gesture through the display of an Avatar rendered in 3D, allows the coach or player to obtain the information and provide a precise diagnosis of the service movement, in addition to analytical feedback for the service training, facilitating correction of the motor gesture, preventing players from training wrongly, and without making an excessive repetitive effort that could impair the service movement, preventing pain and joint injuries. Through the digital signal processing of the serve images, it is possible to obtain specific information by structural temporal modeling of the biomechanics of the serve in tennis, determined through kinematics the technical standards for the variables of the open movement of the serve and to analyze the motor gesture in all segments of levers, planes and anatomical axes of the player.
Aspectos fisiológicos e nutricionais em mudas de citros infectadas por HLB e submetidas a diferentes disponibilidades hídricas
(Universidade Federal de São Carlos, 2021-07-24) Lavorenti, Jéssica Aparecida Lara; Mattos Júnior, Dirceu de; https://lattes.cnpq.br/8599356494482170; Soares, Marcio Roberto; https://lattes.cnpq.br/6337462438517339; https://lattes.cnpq.br/8444643970090631
Citriculture contributes with the largest volume of Brazilian fruit production, obtained from the high productivity of the orchards, as a result of the adoption of technologies such as planting densification, soil fertilization, and irrigation. However, the increase in the incidence of phytosanitary problems, especially huanglongbing (HLB), puts pressure on production costs and leads to a reduction in the sustainability of the sector. The causal agent of HLB is a phloem-restricted bacterium (Candidatus Liberibacter) that impairs the absorption of water and nutrients. Despite the existence of recommendations aimed at reducing plant susceptibility to HLB with better irrigation and soil fertilization management, little is known about the relationship between water availability and physiological and nutritional responses in citrus plants infected with HLB. This study aims to understand the physiological, nutritional and biochemical changes observed in early stages of HLB infection in 'Valência' orange (C. sinensis) plants grafted onto 'Citrumelo Swingle' [Citrus paradisi X Poncirus trifoliata (L.)], subjected to different water supply conditions. The experiment was carried out in pots in a greenhouse and the experimental design used was completely randomized (DIC), in a split-plot scheme, with two infection conditions (HLB+ and HLB-) and two water supply conditions [full irrigation (FI) and deficit irrigation (DI)]. At 75 days after transplanting, the following parameters were evaluated: net photosynthetic rate, transpiration, stomatal conductance, intrinsic efficiency in water use, leaf area and mass, bacterial title in leaves and roots, starch and soluble sugar contents, contents of nutrients and dry mass of leaves, branches, and roots. The results were analyzed by Student's t test at 5% probability. Plants infected with HLB and subjected to irrigation deficit showed lower starch accumulation, higher content of soluble sugars in leaves, higher water use efficiency and higher nutrient content in the shoot. These responses in plants under water deficit were associated with a decrease in bacterial population in previously infected plant parts, as well as a deceleration of disease progress to new canopy parts that developed after infection. The decrease in the bacterial population under more restricted conditions of water supply is important information for future management practices with species that may be tolerant to HLB, given the series of physiological, biochemical and nutritional responses under irrigation deficit.