ABSTRACT
PURPOSE: Use a conference challenge format to compare machine learning-based gamma-aminobutyric acid (GABA)-edited magnetic resonance spectroscopy (MRS) reconstruction models using one-quarter of the transients typically acquired during a complete scan. METHODS: There were three tracks: Track 1: simulated data, Track 2: identical acquisition parameters with in vivo data, and Track 3: different acquisition parameters with in vivo data. The mean squared error, signal-to-noise ratio, linewidth, and a proposed shape score metric were used to quantify model performance. Challenge organizers provided open access to a baseline model, simulated noise-free data, guides for adding synthetic noise, and in vivo data. RESULTS: Three submissions were compared. A covariance matrix convolutional neural network model was most successful for Track 1. A vision transformer model operating on a spectrogram data representation was most successful for Tracks 2 and 3. Deep learning (DL) reconstructions with 80 transients achieved equivalent or better SNR, linewidth and fit error compared to conventional 320 transient reconstructions. However, some DL models optimized linewidth and SNR without actually improving overall spectral quality, indicating a need for more robust metrics. CONCLUSION: DL-based reconstruction pipelines have the promise to reduce the number of transients required for GABA-edited MRS.
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Introduction: Creativity is a recognized quality in various areas, including sports. Within the training processes, various modifications to objectives, game configurations, rules, among other factors, can be considered to favor creative solutions to the tactical problems inherent to soccer. This systematic review aimed to identify the impact of the number of players on the emergence of creative movements in small-sided soccer games, emphasizing deliberate practice. Methods: A systematic review of Scopus, PubMed, Scielo, PsycInfo, SportDiscus and Lilacs databases was performed according to PRISMA guidelines. Eligibility criteria were defined based on the elements of population, context and concept. Only full articles published in scientific journals written in English were included. No period restriction was applied. Results: Five papers were included and the results of studies indicate greater number of actions, variability, and creativity in small-sided games compared to formal soccer matches. When comparing different small-sided game formats, 5 v 5 showed higher values in terms of total number of actions compared to 7 v 7, and the absolute number of original and creative actions tended to decrease as the game format increased. Imbalanced small-sided games format can promote increased exploratory behavior. Structural manipulation in goal positioning in 5 v 5 games may also influence the originality of tactical behaviors, while the use of different ball types in 4 v 4 games appears to decrease fluency values. In 6 v 6 games, fluency and versatility are negatively impacted. Conclusion: Reduced game formats with fewer players and in smaller field dimensions provide more suggestive environment for exploratory behavior, variability and original and creative actions. The protocol was registered on the Open Science Framework (OSF) on 2 December 2022 (DOI: 10.17605/OSF.IO/VN6YZ). Systematic review registration: [https://osf.io/jmf4k/].
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Abstract Aim: This study verified the combined effects of game result and match location on centrality measures based on the interactions of Brazilian handball players. Methods: The sample consisted of 3435 interactions performed by 15 players during 7 official Brazilian Regional Championship matches. Social network analysis was applied to investigate the following network properties: degree of centrality, closeness centrality, degree of prestige, proximity prestige, and network density. Results: Results revealed that playing at home increases closeness centrality (η2 = 0.99; p = 0.01), and network density (η2 = 1.00; p = 0.01). When the handball team lost the game, an increment in the network density in relation to the draw and win scenario was observed (η2 = 1.00; p = 0.01). It was observed that closeness centrality and network density increased when the team had lost and played at home, while when the team was playing away from home and losing, closeness centrality decreased (η2 = 0.99; p = 0.01). Conclusions: In conclusion, contextual variables impact the way that handball players interact during a match.
ABSTRACT
Abstract The study aimed to analyze the core tactical offensive principles and technical efficiency of primary school futsal players. Thirty-three students from a school in Paraná participated in the study. The System of Tactical Assessment in Soccer (FUT-SAT) and the System of Notational Analysis in Small-sided Soccer Games were used for tactical-technical analysis. It was found that the tactical principle "offensive coverage" was most frequently executed by the primary school futsal players (p = 0.01), followed by "width and length" without ball (p < 0.01). Moderate and strong significant correlations were identified between the execution frequency of the core tactical principles "penetration", "offensive coverage", "width and length without ball", "offensive unity" and efficiency in technical skills (from r = 0.43 to r = 0.82, p < 0.05). It is concluded that there is a model of playing near the game center in the presented age group, and that the efficiency of executing technical skills is associated with tactical behavior in game situation.
Resumo O estudo objetivou analisar os princípios táticos fundamentais ofensivos e a eficácia técnica de escolares praticantes de futsal. Participaram do estudo 33 alunos de uma escola no Paraná. Utilizou-se o Sistema de Avaliação Tática no Futebol (FUT-SAT) e o Sistema de Análise Notacional em Jogos Reduzidos de Futebol para análise tático-técnica. Constatou-se que o princípio tático "cobertura ofensiva" foi executado com mais frequência pelos escolares praticantes de futsal (p = 0,01) seguido pelo princípio "espaço sem bola" (p < 0,01). Correlações significativas moderadas e fortes foram identificadas entre a frequência de execução dos princípios táticos fundamentais "penetração", "cobertura ofensiva", "espaço com bola", "unidade ofensiva" e a eficiência em habilidades técnicas (de r = 0,43 a r = 0,82, p < 0,05). Conclui-se que no grupo etário avaliado, existe um modelo de jogar próximo ao centro de jogo e que a eficiência de execução técnica está associada com o comportamento tático em situação de jogo.
