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As one of the latest emerging HVAC technologies, the Variable Refrigerant Flow (VRF) system with heat recovery (HR) configurations has obtained extensive attention from both the academia and industry. Compared with the conventional VRF systems with heat pump (HP) configurations, VRF-HR is capable of recovering heat from cooling zones to heating zones and providing simultaneous cooling and heating operations. This can further lead to substantial energy saving potential and more flexible zonal control. In this paper, a novel model is developed to simulate the energy performance of VRF-HR systems. It adheres to a more physics-based development with the ability to simulate the refrigerant loop performance and consider the dynamics of more operational parameters, which is essential for representing more advanced control logics. Another key feature of the model is the introduction of component-level curves for indoor units and outdoor units instead of overall performance curves for the entire system, and thus it requires much fewer user-specified performance curves as model inputs. The validation study shows good agreements between the simulated energy use from the new VRF-HR model and the laboratory measurement data across all operational modes at sub-hourly time steps. The model has been adopted in the official release of the EnergyPlus simulation program since Version 8.6, which enables more accurate and robust assessments of VRF-HR systems to support their applications in energy retrofit of existing buildings or design of zero-net-energy buildings.

Objective: Hypothalamic signals potently stimulate energy expenditure by engaging peripheral mechanisms to restore energy homeostasis. Previous studies have identified several critical hypothalamic sites (e.g. preoptic area (POA) and ventromedial hypothalamic nucleus (VMN)) that could be part of an interconnected neurocircuit that controls tissue thermogenesis and essential for body weight control. However, the key neurocircuit that can stimulate energy expenditure has not yet been established. Methods: Here, we investigated the downstream mechanisms by which VMN neurons stimulate adipose tissue thermogenesis. We manipulated subsets of VMN neurons acutely as well as chronically and studied its effect on tissue thermogenesis and body weight control, using Sf1Cre and Adcyap1Cre mice and measured physiological parameters under both high-fat diet and standard chow diet conditions. To determine the node efferent to these VMN neurons, that is involved in modulating energy expenditure, we employed electrophysiology and optogenetics experiments combined with measurements using tissue-implantable temperature microchips. Results: Activation of the VMN neurons that express the steroidogenic factor 1 (Sf1; VMNSf1 neurons) reduced body weight, adiposity and increased energy expenditure in diet-induced obese mice. This function is likely mediated, at least in part, by the release of the pituitary adenylate cyclase-activating polypeptide (PACAP; encoded by the Adcyap1 gene) by the VMN neurons, since we previously demonstrated that PACAP, at the VMN, plays a key role in energy expenditure control. Thus, we then shifted focus to the subpopulation of VMNSf1 neurons that contain the neuropeptide PACAP (VMNPACAP neurons). Since the VMN neurons do not directly project to the peripheral tissues, we traced the location of the VMNPACAP neurons' efferents. We identified that VMNPACAP neurons project to and activate neurons in the caudal regions of the POA whereby these projections stimulate tissue thermogenesis in brown and beige adipose tissue. We demonstrated that selective activation of caudal POA projections from VMNPACAP neurons induces tissue thermogenesis, most potently in negative energy balance and activating these projections lead to some similar, but mostly unique, patterns of gene expression in brown and beige tissue. Finally, we demonstrated that the activation of the VMNPACAP neurons' efferents that lie at the caudal POA are necessary for inducing tissue thermogenesis in brown and beige adipose tissue. Conclusions: These data indicate that VMNPACAP connections with the caudal POA neurons impact adipose tissue function and are important for induction of tissue thermogenesis. Our data suggests that the VMNPACAP → caudal POA neurocircuit and its components are critical for controlling energy balance by activating energy expenditure and body weight control.

O objetivo deste estudo de caso foi analisar as percepções de alunos(as) de um curso de Ciências do Esporte no Brasil quanto à importância atribuída e o domínio percebido sobre os conhecimentos e competências do(a) treinador(a) esportivo(a). Utilizamos o questionário de Quinaud et al. (2018), com 192 alunos(as) do primeiro ao quinto ano do curso. Fizemos o uso da estatística descritiva e, após constatarmos a distribuição não normal, recorremos ao teste Kruskal-Wallis para a comparação da importância atribuída e do domínio percebido dentro dos grupos. Nos casos com diferenças significativas utilizamos o teste U de Mann-Whitney, correção de Dun-Bonferroni (p≤0,05) e tamanho de efeito pelo Eta² parcial (Cohen, 1973). Não constatamos diferenças significativas acerca da importância atribuída aos conhecimentos e observamos diferenças em duas competências. Sobre o domínio percebido, constatamos diferenças significativas acerca de todos os conhecimentos e competências, principalmente entre alunos(as) dos primeiros anos comparados aos de 3º, 4º e 5º. Diferentes vivências ao longo do curso parecem auxiliar no desenvolvimento do domínio de conhecimentos e competências dos(as) alunos(as). Considerando que no Brasil há a obrigatoriedade do diploma de graduação para atuar como treinador(a), torna-se importante que os cursos de Educação Física e Esporte prezem pelo desenvolvimento de conhecimentos e competências específicos desta profissão.

Resumo A variabilidade e beleza das ações técnicas individuais do basquetebol são decorrentes das necessidades táticas impostas aos jogadores durante o jogo e fazem parte importante do espetáculo, impactando positivamente os espectadores e mídia. Entre várias formas de fintas, arremessos, passes e bandejas, destacam-se as enterradas, enquanto momento de grande notoriedade no jogo, bem como tema de eventos específicos dedicados a ela no basquetebol masculino. Visando a realização do 1º Torneio de Enterradas no Jogo das Estrelas LBF 2018, o objetivo do estudo foi qual altura do aro necessária para que as jogadoras brasileiras pudessem realizar enterradas. Foi utilizada a altura alcançada no teste de impulsão vertical em progressão de 91 jogadoras participantes das nove equipes na temporada 2018. Verificamos que 25 % dos jogadores masculinos brasileiros de elite enterram em jogos oficiais. Assim, o critério para definir a altura do aro foi que a mesma porcentagem de jogadoras femininas pudessem enterrar, considerando a altura alcançada no teste e a necessidade de passar a bola sobre o aro. Foi determinada a altura de 2.75 m do aro em relação ao solo. Oito jogadoras participaram do evento, sendo quatro brasileiras e quatro argentinas, sendo que cinco delas conseguiram realizar enterradas. Deve-se ressaltar que a altura do aro não foi alterada para os jogos da temporada, e considerar que essa mudança pode não implicar no surgimento de enterradas em partidas oficiais, dado que a dinâmica do jogo é diferente da dinâmica no Torneio de Enterradas e que as jogadoras necessitam de um tempo de adaptação. Palavras-chave: Aro; rendimiento; impulsão; Capacidade Física. Abstract The variability and beauty of basketball's individual technical actions arise from the tactical needs imposed on players during the game, as an important part of the spectacle that positively impacts spectators and media. Among the many feints, throws, passes and layups, are the slam dunks, a notorious moment in the game, and also theme of specific events in men's basketball. In view of the realization of the 1st Slam Dunk Tournament during the 2018 LBF All Stars Games, the aim of the study was to determine the ideal hoop height for Brazilian female players to be able to slam dunk. We analyzed the height achieved in the progressive vertical jump test of 91 female players participating in the nine teams in the 2018 season. Findings suggest that 25% of the elite Brazilian male players slam dunk in official games. Thus, the criteria for defining the hoop height was that the same percentage of female players could slam dunk, considering the height reached on the test and the need to take the ball over the hoop. This resulted in 2.75 m as the height of the rim from the ground. Eight players participated in the event, four Brazilian and four Argentinian, and five of them managed to dunk. It should benoted that the height of the rim has not changed for the regular games of the season, and that this change may not imply the emergence of dunks in official matches, as the game dynamics are different from the dynamics in the Dunk Tournament and that the players need some time to adapt. Keywords: Aro; Performance; Impulsion; Physical Ability. Resumen La variabilidad y hermosura de las acciones técnicas individuales del baloncesto se derivan de las necesidades tácticas impuestas a los jugadores durante el juego y son una parte importante del espectáculo, que impacta positivamente a los espectadores y a la prensa. Entre las muchas maneras de fintas, tiros, pases y entradas, están los mates, como un momento de gran notoriedad en el juego en el baloncesto masculino. Con el objetivo de celebrar el primer “Torneo de mates LBF 2018”, el objetivo del estudio fue determinar la altura del aro necesario para que las jugadoras brasileñas pudieran concretizar los mates. Utilizamos la altura alcanzada en la prueba de salto vertical progresivo de 91 jugadoras de los nueve equipos de la temporada 2018. Encontramos que el 25% de los jugadores masculinos brasileños de élite son capaces de hacer mates en los juegos oficiales. Por lo tanto, el criterio para definir la altura del aro fue que el mismo porcentaje de jugadoras femeninas pudiera concluye mates, considerando la altura alcanzada en la prueba de salto y la necesidad de pasar la pelota sobre el aro. Así, llegamos a la altura del aro desde 2,75 m del suelo. Ocho jugadoras participaron en el evento, cuatro brasileñas y cuatro argentinas, cinco de ellas lograron actuar mates. Cabe señalar que la altura del aro no fue cambiada para los partidos de la temporada, con lo cual esta altura puede no implicar la aparición de mates en esta condición, ya que la dinámica del juego es diferente de la dinámica en el Torneo de mates. Palabras clave: Aro; rendimiento; empuje; Capacidad Física.

Os jogos de ataque por conceitos (JAC) visam estimular jogadores a compreenderem o jogo, solucionarem problemas e criarem vantagens sobre o adversário. O objetivo foi aplicar os JAC para o ensino da fase ofensiva do basquetebol no esporte de participação brasileiro, descrevendo as opiniões dos atletas e seu treinador. Participaram oito atletas do sexo masculino (média de 16,8 ± 1,0 anos), com tempo médio de experiência com o basquetebol de 3,0 ± 1,4 anos, com métodos tradicionais de ensino, e um treinador de 32 anos com oito anos de experiência profissional. Elaboramos os JAC a partir dos conceitos: dividir e passar, passar e cortar, e jogo ao poste. Aplicamos oito sessões de treino, com duração de 90 minutos cada. Realizamos entrevista semiestruturada com o treinador e grupos focais com os atletas, analisadas por análise temática. Nos resultados estabelecemos as categorias opiniões positivas (temas: compreensão da lógica do jogo; aspectos pessoais; e aspectos interpessoais), e negativas (temas: confronto com o novo e tempo de implementação do método). Os JAC foram compreendidos como prazerosos e facilitaram a compreensão da lógica do jogo. Concluimos que os JAC podem ser utilizados para ensino do basquetebol no contexto de participação, com vantagens sobre abordagens pedagógicas tradicionais.

Basketball performance analysis using technical indicators dissociated from the moment they occurred in the game seems to no longer respond to emerging issues of the game as it does not identify the periods when a team’s offensive efficiency has increased or decreased. The aim was to characterize and compare the technical indicators in the positive and negative periods and in the whole game of winning and losing teams in men’s professional basketball. Fourteen games of professional men’s teams of the “Novo Basquete Brasil” Championship in the regular 2011/2012 season were filmed and analyzed. The Kolmogorov-Smirnov test was used to verify data normality. The independent T test was used for variables with normal distribution and the Mann-Whitney test for variables that did not present normal distribution, in order to compare teams’ performance. Analysis in the whole game showed that winning teams had significantly higher averages in successful 3-point field goals but in the positive periods, they showed higher averages for successful free throws, successful layups, defensive rebounds and defensive fouls, and in negative periods, losing teams made more defensive and offensive fouls. The teams’ performance in the whole game may not elucidate the determinant indicators for building the difference in the scoreboard. It is suggested that coaches should identify the periods of best and worst teams’ performance in the game and the indicators involved, preparing teams to overcome the negative periods and obtain more positive periods in the game.