Artificial intelligence to explain the variables that favor the cyanobacteria steady-state in tropical ecosystems: A Bayeasian network approach.

The steady-state is a situation of little variability of species dominance and total biomass over time. Maintenance of cyanobacteria are often observed in tropical and eutrophic ecosystems and can cause imbalances in aquatic ecosystem. Bayeasian networks allow the construction of simpls models that summarizes a large amount of variables and can predict the probability of occurrence of a given event. Studies considering Bayeasian networks built from environmental data to predict the occurrence of steady-state in aquatic ecosystems are scarce. This study aims to propose a Bayeasian network model to assess the occurrence, composition and duration of cyanobacteria steady-state in a tropical and eutrophic ecosystem. It was hypothesized long lasting steady-state events, composed by filamentous cyanobacteria species and directly influenced by eutrophication and drought. Our model showed steady-state lasting between 3 and 17 weeks with the monodominance or co-dominance of filamentous species, mainly Raphidiopsis raciborskii and Planktothrix agardhii. These evens occurred frequently under drought and high turbidity, however higher nutrients concentrations did not increase the probability steady-state occurrence or longer duration. The proposed model appears as a tool to assess the effects of future warming on steady-state occurrence and it can be a useful to more traditional process-based models for reservoirs.

Genetic divergence for adaptability and stability in sugarcane: Proposal for a more accurate evaluation.

The best agro-industrial performance presented by a crop genotype in one environment may not be reproduced in another owing to complex edaphoclimatic variations. Therefore, breeding programs are constantly attempting to obtain, through artificial hybridization, novel genotypes with high adaptability and stability potential. The objective of this study was to analyze genetic divergence in sugarcane based on the genotypic values of adaptability and stability. A total of 11 sugarcane genotypes were analyzed for eight agro-industrial traits. The genotypic values of the traits were determined using mixed model methodology, and the genetic divergence based on phenotypic and genotypic values was measured using the Mahalanobis distance. The distance matrices were correlated using the Mantel test, and the genotypes were grouped using the Tocher method. Genetic divergence is more accurate when based on genotypic values free of genotype-environment interactions and will differ from genetic divergence based on phenotypic data, changing the genotype allocations in the groups. The above methodology can be applied to assess genetic divergence to obtain novel sugarcane genotypes with higher productivity that are adapted to intensive agricultural systems using diverse technologies. This methodology can also be tested in other crops to increase accuracy in selecting the parents to be crossed.

Efeito de uma sessão de treinamento de força sobre a qualidade do sono de adolescentes / Effect of a session of strength training on the quality adolescents sleeping / Efecto de una sesión de entrenamiento de fuerza en la calidad del sueño de los adolescentes

INTRODUÇÃO: o sono é uma função biológica fundamental para a conservação da energia e a restauração do metabolismo energético. OBJETIVO: analisar o efeito de uma sessão do treinamento de força realizada em diferentes horários sobre a qualidade do sono de adolescentes e examinar se a relação entre a melhoria da qualidade do sono e o horário da sessão de treino se altera após o ajuste para idade. MÉTODOS: participaram do estudo seis estudantes do sexo masculino moradores internos do IFPE - Campus Vitória de Santo Antão, PE, Brasil. Foram realizadas três sessões de treinamento de força em diferentes horários manhã, tarde e noite, durante 12 semanas. A escala OMINI-RES foi utilizada para percepção do esforço. A qualidade do sono foi avaliada pelo Índice de Qualidade do Sono de Pittsburgh PSQI. Ainda foram avaliadas variáveis antropométricas massa corporal, estatura, IMC e a composição corporal % gordura, massa gorda e massa magra. RESULTADOS: foram observadas diferenças entre as sessões de treino realizadas em diferentes horários e a diagnose de qualidade do sono manhã: P < 0,001; tarde: P = 0,001; noite: P = 0,047. Houve correlação entre a sessão de treino realizada pela manhã r = 0,95 e à tarde r = 0,92 e a diagnose de qualidade do sono. Utilizando o modelo de regressão linear, as sessões de treinamento de força realizadas pela manhã R2 = 0,91 e tarde R2 = 0,75 explicaram de forma significativa a melhora da qualidade do sono em adolescentes, mesmo após o controle pela idade. CONCLUSÃO: as sessões de treinamento de força realizadas pela manhã e tarde apresentaram melhor resposta de qualidade do sono de adolescentes. .

INTRODUCTION: sleep is a fundamental biological function for energy conservation and restoration of the energy metabolism. OBJECTIVE: To analyze the effect of a session of strength training performed at different times on the quality of sleep of adolescents and to examine the relationship between improving the quality of sleep and the time of the training session changes after adjusting for age. METHODS: participated in this investigation six male students internal residents of IFPE - Vitória de Santo Antão, PE, Brazil. Three strength training sessions were performed at different times morning, afternoon and evening for 12 weeks. The OMNI-RES scale was used to perceived exertion. Sleep quality was assessed using the Pittsburgh Sleep Quality Index PSQI. Anthropometric variables body weight, height, BMI and body composition %fat, fat mass and lean mass were evaluated. RESULTS: differences were observed between training sessions at different times and the diagnosis of sleep quality morning: P<0.001; afternoon: P=0.001; evening: P=0.047. There was a correlation between the training session held in the morning r=0.95 and in the afternoon r=0.92 and the diagnosis of sleep quality. Using the linear regression model, the strength training sessions held in the morning R2=0.91 and afternoon R2=0.75 explained the significantly improved quality of sleep in adolescents, even after adjusting for age. CONCLUSION: the strength training sessions in the morning and afternoon showed better response in the quality of sleep of adolescents. .

INTRODUCCIÓN: el sueño es una función biológica básica en la conservación de la energía y la restauración del metabolismo energético. OBJETIVO: analizar el efecto de una sesión de entrenamiento de fuerza realizada en diferentes momentos en la calidad del sueño de los adolescentes y examinar si la relación entre la mejora de la calidad del sueño y el horario de la sesión de entrenamiento cambia después del ajuste para la edad. MÉTODOS: participaron del estudio seis estudiantes varones residentes internos de IFPE - Campus Vitória de Santo Antão, PE, Brasil. Tres sesiones de entrenamiento de fuerza se llevaron a cabo en diferentes momentos mañana, tarde y noche durante 12 semanas. La escala OMNI-RES se utilizó para el esfuerzo percibido. La calidad del sueño se evaluó mediante el Índice de Calidad del Sueño de Pittsburgh PSQI. Las variables antropométricas también fueron evaluadas peso, talla, índice de masa corporal y la composición corporal % de grasa, la masa grasa y la masa magra. RESULTADOS: se observaron diferencias entre las sesiones de entrenamiento realizadas en diferentes momentos y el diagnóstico de la calidad del sueño mañana: P < 0,001; tarde: P = 0,001; noche: P = 0,047. Hubo una correlación entre la sesión de entrenamiento realizada en la mañana r = 0,95 y la tarde r = 0,92 y el diagnóstico de la calidad del sueño. Usando el modelo de la regresión lineal las sesiones del entrenamiento de fuerza llevadas a cabo en la mañana R2 = 0,91 y R2 = 0,75 explicaron de modo significativo la mejora de la calidad del sueño en los adolescentes, incluso después del ajuste por edad. CONCLUSIÓN: las sesiones de entrenamiento de fuerza en la mañana y por la tarde tenían mejor respuesta de la calidad del sueño de adolescentes. .