Pilot evaluation of an interactive multimedia platform to provide nutrition education to Portuguese adolescents.

BACKGROUND: Obesity prevalence has been rising worldwide and currently is one of the most serious public health problems. Nutrition literacy is important to the development of healthier habits that could help prevent and stem obesity and overweight. The aim of this study was to evaluate the impact of using a multimedia web platform to provide nutrition education to Portuguese adolescents. METHODS: The intervention consisted in a two-week period in which students (n = 1291) had access to an interactive multimedia web platform with nutritional content, and designed for a self-paced learning experience. Students completed a knowledge questionnaire at baseline and immediately after the end of the intervention. RESULTS: The results obtained revealed that 85.8% of the students increased their nutrition knowledge. No gender differences were observed post-intervention. There were significant differences in the knowledge acquisition regarding age (P < 0.001). The baseline knowledge seemed to influence the learning process. CONCLUSIONS: Overall, the intervention had a positive impact. The preliminary results observed will be important for the improvement of the intervention, though they need to be confirmed by further research. Nevertheless, it is safe to say that technology-based assets can be important tools to incorporate and complement health-related interventions in schools.

Neuromuscular and motor patterns in breaststroke technique / Padrões motores e musculares na técnica de bruços

Abstract The aim of this study was to analyze the inter-temporal neuromuscular and motor patterns in breaststroke technique. Five national level male swimmers performed 200 m breaststroke at maximal effort. Electromyography data onbiceps brachii, deltoid anterior, pectoralis major and triceps brachiiwere analysed. The relative duration of active and non-active phase and the average rectified value for the neuromuscular patterns were recorded. The swim bouts were videotaped in sagittal plane with a pair of cameras and the Theme software 5.0 was used toanalyse the detected patterns in each swimmer. The neuromuscular pattern revealed that by the average rectified value the biceps brachiiand triceps brachiiwere increased at the end of the test for swimmers 1 and 5, while biceps brachii. deltoid anteriorand pectoralis majorwere increased for swimmers 2 and 4. Different motor patterns between cycles, and between swimmers were observed.We found similarities between the swimmers, adjusting their style to the technical model. The absence of a neuromuscular pattern for all swimmers could be related to different technical models used by each swimmer, as presented in the motor patterns. These findings suggested that each swimmers adapted their own motor and neuromuscular pattern in a unique and distinct way.

Resumo O objetivo deste estudo consistiu em analisar a relação entre os padrões neuromusculares e motores na técnica do nado de peito. Cinco nadadores masculinos de nível nacional realizaram 200 mnado peito na máxima intensidade.Foram registrados dados de Electromiografia do bicepsbrachii, deltoid anterior, pectoralis major etricepsbrachii. A duração relativa da fase ativa e não ativa e o valor médio retificado dos padrões neuromusculares foram analisados. Os percursos de nado foram gravados no plano sagital e analisados para detectar os padrões motores de cadanadador através do software THÉME software 5.0. Os padrões neuromusculares indicaram, por meio do valor médio retificado que a atividade dos músculos bíceps brachii e tríceps brachii aumentam no final do teste para o nadador 1 e 5, enquanto que o bíceps brachii. deltoid anterior. pectoralis major aumentam para o nadador 2 e 4. Diferentes padrões motores entre ciclos e entre nadadores foram observados, indicando que existem semelhanças entre eles, levando a um ajuste do estilo e modelo técnico de nado. A ausência de um padrão neuromuscular para todos os nadadores poderá estar relacionada com os diferentes modelos técnicos utilizados por cada nadador, como demonstrado nos padrões motores. Esses resultados sugerem que cada nadador adapta o seu padrão motor e muscular de uma forma única e distinta.

Neoadjuvant Trabectedin plus Radiotherapy in High-Grade Sarcoma of the Leg: A Case Report.

Here, we present the case of a 78-year-old male patient with undifferentiated spindle cell sarcoma on the posteromedial surface of the right leg who experienced a long-lasting progression-free survival. Due to an underlying cardiac disease, the patient was not suitable for anthracyclines. In September 2015, he received first-line chemotherapy with trabectedin (Yondelis®) at the approved dosage and regimen - concomitant with external radiotherapy (RT). After the first 9 cycles of trabectedin plus RT given in the neoadjuvant setting, the patient underwent surgical resection. At that stage, we observed a very good pathological response with 80% of necrotic area. The patient resumed the therapy with trabectedin; however, approximately 5 months later, we observed a new nodular heterogeneous lesion with ill-defined margins in the right leg and suggestive of tumor relapse. Subsequently an above-the-knee amputation was performed, and the patient resumed his trabectedin therapy with the same dosage and regimen. In January 2018, almost 2 1/2 years after the start of trabectedin treatment and 30+ cycles of trabectedin, the patient is locoregionally and distant metastatically disease-free. Currently, the treatment with trabectedin is maintained without any significant serious toxicity. Future clinical trials are needed to gain additional insights into the role of trabectedin maintenance therapy until disease progression in the neoadjuvant setting and to identify predictive and prognostic criteria for response to trabectedin in patients with advanced sarcoma.

The 3D CFD study of gliding swimmer on passive hydrodynamics drag

The aim of this study was to analyze the effect of depth on the hydrodynamic drag coefficient during the passive underwater gliding after the starts and turns. The swimmer hydrodynamics performance was studied by the application of computational fluid dynamics (CFD) method. The steady-state CFD simulations were performed by the application of k - omega turbulent model and volume of fluid method to obtain two-phase flow around a three-dimensional swimmer model when gliding near water surface and at different depths from the water surface. The simulations were conducted for four different swimming pool size, each with different depth, i.e., 1.0, 1.5, 2.0 and 3.0 m for three different velocities, i.e., 1.5, 2.0 and 2.5 m/s, with swimmer gliding at different depths with intervals of 0.25 m, each starting from the water surface, respectively. The numerical results of pressure drag and total coefficients at individual average race velocities were obtained. The results showed that the drag coefficient decreased as depth increased, with a trend toward reduced fluctuation after 0.5m depth from the water surface. The selection of the appropriate depth during the gliding phase should be a main concern of swimmers and coaches.

Relationship between origin of shot and occurrence of goals in competitive men's water polo matches / Relacao entre a origem do arremesso e a ocorrencia do gol em competicao no polo aquatico masculino

Although some similar studies exist in water polo, there are no reports showing a possible association between the occurrence of goals and the origin of shots. The objective of this study was to correlate the origin of shot and the occurrence of goals in an official men's water polo match. Nine teams that competed in seven final matches of the Third National Men's Water Polo League were evaluated. The games were recorded using a camera installed along the length of the pool. Pearson's chi-square test was used to correlate the categorical variables studied. The effect size was calculated by the ratio between the chance of occurrence of a center goal and the chance of occurrence of a goal scored from the lateral position. An α value < 0.05 was adopted in all cases. There was a significant association between the occurrence of goals and origin of shot, with X2 (2) = 14.89 and p = 0.001, i.e., the proportion of goals scored from the center position was higher than that of goals scored from the lateral position. A center shot was 2.70 times more likely to be converted to a goal by the attacker. It can be concluded that a center shot presented a higher chance to be converted to a goal. This finding might be explained by the inability of the technical-tactical defense to organize, permitting closer proximity of the attackers. The same situation does not seem to apply to high-level technical-tactical matches.

Apesar da realização de algumas pesquisas desta natureza no polo aquático, não foram encontrados estudos que mostrem a possível associação entre a ocorrência do gol com a origem da realização do arremesso. Este estudo objetivou relacionar a origem do arremesso e a ocorrência do gol em uma competição oficial de polo aquático masculino. Foram avaliadas nove equipes que disputaram os sete jogos da fase final da III Liga Nacional de Polo Aquático Masculino. Os jogos foram gravados, utilizando-se uma filmadora localizada no sentido do comprimento do campo de jogo. Utilizou-se o Teste Qui-quadrado de Pearson com o objetivo de correlacionar as variáveis categóricas observadas. O tamanho do efeito foi calculado por meio da razão entre a chance do gol ocorrer pela região central, pela chance do gol ocorrer pelas laterais. Em todos os casos, considerou-se α < 0,05. Houve uma associação significativa entre a origem do arremesso e a ocorrência do gol, com X2 (2) = 14,89, (p = 0,001). Ou seja, a proporção de gols realizados pela região central da área de jogo foi maior do que aquela realizada pelas laterais. Um arremesso realizado pela região central teve 2,70 mais chances de ser convertido em gol a favor do atacante. Conclui-se que o arremesso realizado pela região central teve maior chance de ser convertido em gol. Isso pode dever-se a uma incapacidade técnico-tática da defesa se organizar e permitir maior proximidade dos atacantes. Este mesmo cenário parece não se repetir em jogos de maior qualidade técnico-tática.

Performance progression in Brazilian middle-distance runners from early training to peak performance: a pilot study / Evolução da performance de meio-fundistas Brasileiros da formação ao pico de rendimento: um estudo piloto

The aim of this study was to evaluate performance progression in Brazilian middle-distance runners based on the progression of their sports results from early training to peak performance. The sample consisted of the 10 best performance times (800 m and 1500 m) achieved by male runners aged 15 to 19 years in national rankings between 2001 and 2010. The 800-m performance times estimated with the models were 119.14±1.79 s at 15 years of age; 114.36±1.07 s at 16 years; 113.25±1.81 s at 17 years; 110.71±1.60 s at 18 years, and 109.73±1.17 s at 19 years. The prediction of 1500-m performance was 253.89±4.84 s at 15 years of age; 243.40±1.67 s at 16 years; 238.53±1.55 s at 17 years; 232.49±1.59 s at 18 years, and 230.48±2.28 s at 19 years. It is concluded that Brazilian male middle-distance runners achieve their best performance at 22.69±0.42 years of age in the 800-m event and at 22.29±0.34 years in the 1500-m event. These values are within the lower limit described in the literature as optimal age.

O objetivo deste estudo foi analisar a evolução da performance dos corredores de Meio-Fundo Brasileiros com base na progressão dos resultados desportivos obtidos no processo de formação e no pico de rendimento. A amostra constituiu-se dos dez melhores tempos dos rankings nacionais de 2001 a 2010, alcançados pelos corredores nas provas de MF, na faixa etária de 15 a 19 anos, do sexo masculino. Os resultados expressos pelo modelo matemático encontrado apresentam para os 800m aos 15 anos: 119,14±1,79s; 16 anos: 114,36±1,07s; 17 anos: 113,25±1,81s; 18 anos: 110,71±1,60s; 19 anos: 109,73±1,17s. Para os 1.500m constatou-se uma predição da performance aos 15 anos em: 253,89±4,84s; 16 anos: 243,40±1,67s; 17 anos: 238,53±1,55s; 18 anos: 232,49±1,59s; 19 anos: 230,48±2,28s. Conclui-se que a idade ótima de obtenção dos melhores resultados desportivos para os corredores de MF do sexo masculino, no Brasil, em provas de 800m, apresenta-se aos 22.69±0.42 anos e nas provas de 1.500m aos 22.29±0.34 anos. Estes valores situam-se no limite inferior do referido na literatura.

Revisão da produção científica internacional sobre crenças, atitudes, opiniões e comportamentos docentes na inclusão em educação física / Revision of international scientific production about beliefs, attitudes, opinions and behaviors of teachers in the inclusion in physical education

A presente investigação buscou analisar criticamente estudos indexados em inglês na base de dados ISI Web of Science que tenham como objetivo principal ou secundário verificar as crenças, atitudes, opiniões e comportamentos docentes associados à inclusão de pessoas com deficiência na Educação Física regular na literatura internacional. Realizaram-se buscas na base de dados ISI Web of Science entre os períodos de 1994 a 2010. Oito artigos fizeram parte das análises envolvendo esta temática. Pode-se concluir que a produção científica Internacional nas bases de dados adotadas evidenciou que os professores de Educação Física julgam que suas escolas estão mal preparadas e que há necessidade de experiências práticas, informações e formação para o ensino de pessoas com deficiência, pois os docentes que mantiveram atitudes menos favoráveis são os mesmos que relataram ter pouca ou nenhuma formação na área da Educação Física adaptada, ocasionando assim, um sentimento de despreparo profissional...

This research aimed to critically analyze studies indexed in English in the database ISI Web of Science that have as a main or secondary objective verify beliefs, attitudes, opinions and behaviors of teachers associated to inclusion of people with disabilities in regular physical education in the international literature. Searches were made in the database ISI Web of Science between the periods 1994 to 2010. Eight articles were part of the analysis involving this issue. It can be concluded that international scientific production in the databases adopted showed that physical education teachers believe that their schools are not well prepared and need practical experience, information and training to teach people with disabilities, because teachers who remained less favorable attitudes are the same who reported having little or no training in adapted Physical Education, thus causing a feeling of lack of professional training...

Effect of wearing a swimsuit on hydrodynamic drag of swimmer

The purpose of this study was to analyse the effect of wearing a swimsuit on swimmer's passive drag. A computational fluid dynamics analysis was carried out to determine the hydrodynamic drag of a female swimmer's model (i) wearing a standard swimsuit; (ii) wearing a last generation swimsuit and; (iii) with no swimsuit, wearing light underwear. The three-dimensional surface geometry of a female swimmer's model with different swimsuit/underwear was acquired through standard commercial laser scanner. Passive drag force and drag coefficient were computed with the swimmer in a prone position. Higher hydrodynamic drag values were determined when the swimmer was with no swimsuit in comparison with the situation when the swimmer was wearing a swimsuit. The last generation swimsuit presented lower hydrodynamic drag values, although very similar to standard swimsuit. In conclusion, wearing a swimsuit could positively influence the swimmer's hydrodynamics, especially reducing the pressure drag component.

Physical activity and determinants of sedentary behavior in Brazilian adolescents from an underdeveloped region.

The purpose of the study was to analyze the physical activity and the determinants of sedentary behavior in 1,268 Brazilian adolescents (638 girls, 630 boys) between the ages of 15 and 18 years, randomly selected from a relatively underdeveloped region. Data were collected from a community-based survey in the city of João Pessoa, Paraiba, Brazil. Information related to physical activity was derived on the short version of the International Physical Activity Questionnaire. The prevalence of sedentary behavior was 28.2% for girls and 19.1% for boys, whilst 28.9% of the girls and 36.7% of the boys showed high physical activity. The sedentary behavior varied by sociodemographic and environmental determinants studied. Parents' education, socioeconomic status, school's characteristics, transport to school, paid work, smoking, alcohol use, and BMI scores were significantly related to sedentary behavior for boys and girls.

Análise dos parâmetros cinemáticos determinantes do desempenho na prova de 200 m nado livre / Analysis of the determinant kinematical parameters for performance in the 200-m freestyle swimming event

Os objetivos deste estudo foram: i) caracterizar o nado submáximo e máximo do ponto de vista cinemático; ii) verificar a influência das variáveis cinemáticas na prova máxima de 200 metros crawl. Nove nadadores de elite nacionais realizaram dois testes: um submáximo, descontínuo de intensidade progressiva; outro máximo, que consistiu em uma simulação de uma prova de 200 m crawl. Foram estudados os parâmetros cinemáticos gerais da mecânica da braçada, a duração de cada fase do ciclo gestual, a velocidade do centro de massa e a variação intracíclica da velocidade horizontal. Verificaram-se diferenças cinemáticas significativas da frequência gestual, velocidade de deslocamento do centro de massa, duração total do ciclo gestual, duração da ação subaquática propulsora e da velocidade do centro de massa na fase de recuperação entre os testes. Identificou-se associações significativas entre o teste máximo e algumas variáveis cinemáticas como a velocidade do centro de massa e índice de nado.

The main aims of this study were i) to perform a kinematic characterization of sub and maximal swimming speed; ii) to investigate the associations between the kinematic profiles and the 200 m front crawl style. Nine national level male swimmers performed two speed tests: a submaximal discontinuous speed trial of progressive speed intensity, and a maximal one, simulating a 200 m front crawl style. The stroke general kinematic parameters, the phases duration of the stroke cycle, the velocity of the centre of mass and the intra cyclic variation of the horizontal velocity were herein studied. Significant kinematic differences in relation to stroke rate, horizontal velocity of the centre of mass, total cycle duration, absolute and relative duration of the propulsive sub aquatic action and the velocity of the centre of mass during the arms recovery were compared between the speed tests. Significant correlations between the performance in the maximal speed and some kinematic variables were observed.

Non-genomic vasorelaxant effects of 17ß-estradiol and progesterone in rat aorta are mediated by L-type Ca2+ current inhibition.

AIM: The sex hormones 17ß-estradiol (ßES) and progesterone (PRG) induce rapid non-genomic vasodilator effects which could be protective for the cardiovascular system. The purpose of this study was to analyze the mechanisms underlying their vasodilator effect in rat aortic smooth muscle preparations. METHODS: Endothelium-denuded aorta artery rings were prepared from male Wistar rats and incubated in an organ bath. The contractions of the preparation were recorded through isometric transducers. The effects of the hormones on K(+) current and L-type Ca(2+) current (LTCC) were analyzed by using the whole cell voltage-clamp technique in A7r5 cells. RESULTS: Both ßES and PRG (1-100 µmol/L) concentration-dependently relaxed the endothelium-denuded aortic rings contracted by (-)-Bay K8644 (0.1 µmol/L) or by KCl (60 mmol/L). The IC(50) values of the two hormones were not statistically different. The K(V) channel blocker 4-aminopyridine (2 mmol/L), BK(Ca) channel blocker tetraethylammonium (1 mmol/L) and K(ATP) channel blocker glibenclamide (10 µmol/L) did not significantly modify the relaxant effect of the hormones. On the other hand, the blockage of the intracellular ßES and PRG receptors with estradiol receptor antagonists ICI 182,780 (1 µmol/L) and PRG receptor antagonist mifepristone (30 µmol/L), respectively, did not significantly modify the relaxant action of the hormones. In A7r5 cells, both the hormones (1-100 µmol/L) rapidly and reversibly inhibited the basal and BAY-stimulated LTCC. However, these hormones had no effect on the basal K(+) current. CONCLUSION: The vasorelaxant effects of ßES and PRG are due to the inhibition of LTCC. The K(+) channels are not involved in the effects.

Aptidão física relacionada à saúde de escolares: programa fitnessgram / Health-related physical fitness of schoolchildren: the fitnessgram program

O estudo identificou a proporção de crianças e adolescentes da população escolar de Montes Claros, Minas Gerais, Brasil, que atendem aos critérios referenciados para a saúde a partir de escores equivalentes aos componentes de aptidão física. A amostra foi constituída por 2.849 sujeitos (1.457 moças e 1.392 rapazes), com idades entre seis e 18 anos. Os componentes da aptidão física foram avaliados mediante bateria de testes composta por cinco itens: "sentar-e-alcançar" alternado, abdominal modificado, elevação do tronco, puxada em suspensão na barra modificado e caminhada/corrida de "vai-e-vem", adotando-se pontos de corte para gênero e idade sugeridos pelo Fitnessgram. Mediante análise dos resultados foi possível observar que a proporção de escolares que atenderam às exigências motoras mínimas estabelecidas que possam satisfazer aos critérios referenciados para a saúde não foi maior que 8%, e a quantidade de jovens que alcançaram os critérios foi menor a partir dos 10 anos de idade em ambos os sexos. Os dados mostram, ainda, que grande parte dos jovens estudados demonstrou componentes de aptidão física que podem comprometer melhor estado de saúde, apontando para urgente necessidade de implementar programas de intervenção direcionados ao incremento da prática de exercício físico na população escolar.

The study identified the proportion of children and adolescents of the school population from Montes Claros, Minas Gerais, Brazil, who meet the health-related criteria determined by physical fitness components. The sample was composed of 2,849 subjects (1,457 girls and 1,392 boys), with age range between 6 and 18 years. The physical fitness components were assessed by a test battery of five items: back-saver sit-and-reach; curl-up; trunk-lift; push-up and endurance run (PACER), following cut off-points for gender and age suggested by the Fitnessgram. It was possible to observe with the obtained results that the proportion of schoolchildren that reached the minimum motor requirements established was not higher than 8%, and the global amount able to meet the health-related criteria was lower from 10 years of age in both genders. The data also show that great part of the studied youngsters demonstrate physical fitness components that could compromise a better health status, indicating the urgent need of implementing intervention programs addressed to the improvement of the practice of physical exercise in the school population.

Cyclic nucleotide-dependent relaxation pathways in vascular smooth muscle.

Vascular smooth muscle tone is controlled by a balance between the cellular signaling pathways that mediate the generation of force (vasoconstriction) and release of force (vasodilation). The initiation of force is associated with increases in intracellular calcium concentrations, activation of myosin light-chain kinase, increases in the phosphorylation of the regulatory myosin light chains, and actin-myosin crossbridge cycling. There are, however, several signaling pathways modulating Ca(2+) mobilization and Ca(2+) sensitivity of the contractile machinery that secondarily regulate the contractile response of vascular smooth muscle to receptor agonists. Among these regulatory mechanisms involved in the physiological regulation of vascular tone are the cyclic nucleotides (cAMP and cGMP), which are considered the main messengers that mediate vasodilation under physiological conditions. At least four distinct mechanisms are currently thought to be involved in the vasodilator effect of cyclic nucleotides and their dependent protein kinases: (1) the decrease in cytosolic calcium concentration ([Ca(2+)]c), (2) the hyperpolarization of the smooth muscle cell membrane potential, (3) the reduction in the sensitivity of the contractile machinery by decreasing the [Ca(2+)]c sensitivity of myosin light-chain phosphorylation, and (4) the reduction in the sensitivity of the contractile machinery by uncoupling contraction from myosin light-chain phosphorylation. This review focuses on each of these mechanisms involved in cyclic nucleotide-dependent relaxation of vascular smooth muscle under physiological conditions.

Perfil de força isocinética dos rotadores dos ombros em jovens nadadores / Shoulder rotator isokinetic strength profile in young swimmers

Considerando que alguns estudos sugerem que desequilíbrios musculares dos rotadores dos ombros estão relacionados com dores e lesões na articulação e que não existem dados normativos para jovens nadadores, o objetivo deste estudo foi: i) caracterizar o equilíbrio e fadiga musculares bem como o perfil de força isocinética dos rotadores dos ombros em nadadores jovens; ii) comparar os resultados entre nadadores com jovens não praticantes; iii) contribuir para a criação de dados normativos de rácios unilaterais dos rotadores do ombro. Foi avaliada a força isocinética com ações concêntricas dos rotadores e respectivos rácios unilaterais (quociente entre torque dos rotadores externos e internos) em 60 nadadores (idade: 14,55 ± 0,5 anos; massa corporal: 61,16 ± 7,08 kg) e 60 não praticantes (idade: 14,62 ± 0,49 anos; massa corporal: 60,22 ± 10,01 kg). Com um dinamômetro isocinético (Biodex System 3), avaliou-se na posição de sentado (90º de abdução e de flexão do cotovelo), às velocidades angulares de 60º.s-1 e 180º.s-1. Os resultados dos índices de fadiga não revelaram diferenças entre grupos. Os nadadores apresentaram rácios unilaterais entre os 73,39±17,26% no membro dominante (MD) e 77,89±15,23% no membro não dominante (MND), para avaliações efetuadas a 60º.s-1; a 180º.s-1, obtivemos resultados entre 74,77±13,99% para MD e 70,11±14,57% para MND. Os nadadores apresentaram um maior desequilíbrio muscular, sendo a capacidade de produção de força dos rotadores internos (significativamente superior nos nadadores) o que os distingue do grupo de não praticantes.

Considering that some studies suggest that shoulder rotators muscle imbalances are related to joint pain and injury, and that there are no normative data for young swimmers, the aim of this study was: i) to describe the muscle balance, fatigue and isokinetic strength profile of the shoulder rotators in young swimmers; ii) to compare the results between swimmers and a group of young non-practitioners; iii) to contribute to the acquisition of normative data of unilateral ratios of shoulder rotators. We evaluated the shoulder rotators concentric strength and unilateral ratios (ratio between torque of external and internal rotators) of 60 swimmers (age: 14.55 ± 0.5 years old; body mass: 61.16 ± 7.08 kg) and 60 non-practitioners (age: 14.62 ± 0.49 years old; body mass: 60.22 ± 10.01 kg). The evaluation was performed in the sitting position (90º abduction and elbow flexion) at 60º.s-1 and 180º.s-1 angular speeds using an isokinetic dynamometer (Biodex System 3). The results of the fatigue ratios revealed no differences between the groups. Swimmers showed unilateral ratios of 73.39 ± 17.26% in the dominant limb (DL) and 77.89 ± 15,23% in the non-dominant limb (NDL) for assessments at 60º.s-¹. At 180º.s-1, ratios were 74.77± 13.99% for DL and 70.11 ± 14.57% for NDL. Swimmers presented greater muscle imbalance, and differed from non-practitioners in the ability to produce power with the internal rotators, which was significantly higher in the former group.

Validação de equações preditivas da área de secção transversa do tronco / Validation of predictive equations of the cross-sectional area of the human trunk

O objectivo do estudo foi desenvolver e validar equações preditivas da área de secção transversa do tronco humano, Os modelos foram desenvolvidos para o sexo masculino e de acordo com o nível competitivo, A amostra foi composta por 152 sujeitos, todos praticantes de Natação Pura desportiva, com idades entre os 10 e os 32 anos de idade, Para o desenvolvimento dos modelos foi utilizado um grupo de sujeitos para estimar a equação e um outro para validar. Foram avaliadas as seguintes características antropométricas: (i) massa corporal; (ii) estatura; (iii) diâmetro bi-acromial; (iv) diâmetro tóraco-sagital; (v) perímetro peitoral e (vi) área de secção transversal do tronco. Os modelos preditivos foram desenvolvidos através de análise de regressão linear múltipla passo-a-passo e num dos casos, com recurso ao nível competitivo enquanto variável dummy. Todos os modelos desenvolvidos incluíram como variáveis independentes o diâmetro tóraco-sagital e o perímetro peitoral (0,32 ≤ R² ≤ 0,48; P < 0,01). No processo de validação entre as áreas de secção transversal do tronco medida e estimada, não se verificaram diferenças significativas entre valores médios (P > 0,05), as regressões lineares simples foram moderadas (0,23 ≤ R² ≤ 0,39; 0,01 ≤ P ≤ 0,001) e o critério de Bland Altman foi em todos os casos cumprido. Pode concluir-se que os modelos desenvolvidos para nadadores masculinos, e de acordo com o nível competitivo, predizem com validade a área de secção transversa do tronco de nadadores.

The objective of this study was to develop and validate predictive equations of the cross-sectional area of the human trunk. The models were developed for males according to their level of expertise. The sample comprised 152 male subjects, all of them with a background in competitive or recreational swimming. Their ages ranged between 10 and 32 years. Two different groups of subjects were used to estimate and validate the equation. The following anthropometric characteristics were assessed: (i) body weight, (ii) height, (iii) biacromial diameter, (iv) sagittal thoracic diameter, (v) chest circumference, and (vi) cross-sectional area of the trunk. Predictive models were developed using stepwise multiple linear regression analysis. One of the models used level of expertise as a dummy variable. All models included sagittal thoracic diameter and chest circumference as independent variables (0.32 ≤ R² ≤ 0.48; P < 0.01). The validation process of the measured and estimated cross-sectional area of the trunk did not reveal any significant differences between the mean values (P > 0.05). The simple linear regressions were moderate (0.23 ≤ R² ≤ 0.55; 0.01 ≤ P ≤ 0.001), and the Bland-Altman criterion was met in all cases. Therefore, our findings suggest that the models developed for male swimmers according to their level of expertise are able to provide a valid prediction of the cross-sectional area of the trunk.

Effects of social and environmental determinants on overweight and obesity among Brazilian schoolchildren from a developing region / Efectos de los determinantes sociales y ambientales sobre la obesidad y el sobrepeso en escolares de una región en desarrollo del Brasil

OBJECTIVE: To identify the social and environmental determinants most strongly associated with overweight and obesity in Brazilian schoolchildren from a developing region. METHODS: Data were collected from a community-based survey of schoolchildren from the Valley of Jequitinhonha, Minas Gerais, Brazil. The sample was composed of 5 100 school children aged 6-18 years. Overweight and obesity were defined by body mass index based on the current method recommended by the World Health Organization in 2007. Social and environmental determinants were collected by using a structured questionnaire. RESULTS: The prevalence of overweight and obesity was 11.1 percent and 2.7 percent in girls and 8.2 percent and 1.5 percent in boys, respectively. The chance of overweight was higher in schoolchildren who engaged in remunerated work (odds ratio [OR] = 2.19, 95 percent confidence interval [CI] 1.30- 3.26), whose parents had higher education levels (OR = 1.52, 95 percent CI 1.12-2.07), who had two or fewer siblings (OR = 1.74, 95 percent CI 1.21-2.49), and who were in a high economic class (OR = 1.93, 95 percent CI 1.32-2.85). Schoolchildren who traveled by car to school (OR = 1.50, 95 percent CI 1.14-1.91), lived < 5 km from school (OR = 1.64, 95 percent CI 1.06-2.39), and consumed foods sold in the school cafeteria (OR = 1.56, 95 percent CI 1.19-2.16) presented high odds of being overweight. CONCLUSIONS: The background from a particular region of a country should be considered when implementing preventive measures regarding overweight and obesity, especially for very poor, developing regions like the Valley of Jequitinhonha. Measures taken should consider a multilevel intervention that includes the family, school, and physical environment.

OBJETIVO: Identificar los determinantes sociales y ambientales más firmemente asociados con el sobrepeso y la obesidad en niños que asisten a la escuela en una región en desarrollo del Brasil. MÉTODOS: Se recopilaron los datos de una encuesta comunitaria llevada a cabo en niños inscritos en escuelas del valle de Jequitinhonha, Minas Gerais (Brasil). La muestra estuvo integrada por 5 100 escolares de 6 a 18 años de edad. El sobrepeso y la obesidad se definieron según el índice de masa corporal, con base en el método actualmente recomendado por la Organización Mundial de la Salud (2007). Los determinantes sociales y ambientales se recopilaron mediante un cuestionario estructurado. RESULTADOS: La prevalencia del sobrepeso y de la obesidad fue de 11,1 por ciento y 2,7 por ciento en niñas y de 8,2 por ciento y 1,5 por ciento en niños, respectivamente. Las probabilidades de tener sobrepeso fueron mayores en los escolares que desempeñaban un trabajo remunerado (razón de probabilidades [RP] = 2,19; intervalo de confianza [IC] de 95 por ciento, 1,30-3,26); en aquellos cuyos padres tenían niveles superiores de educación (RP = 1,52; IC de 95 por ciento, 1,12-2,07); en quienes tenían dos o menos hermanos (RP = 1,74; IC de 95 por ciento, 1,21-2,49); y en los de clase económica alta (RP = 1,93; IC de 95 por ciento, 1,32-2,85). Presentaron altas probabilidades de tener sobrepeso los niños que viajaban en automóvil a la escuela (RP = 1,50; IC de 95 por ciento, 1,14-1,91), los que vivían a < 5 km de la escuela (RP = 1,64; IC de 95 por ciento, 1,06-2,39) y los que consumían los alimentos que se venden en la cafetería de la escuela (RP = 1,56; IC de 95 por ciento, 1,19-2,16). CONCLUSIONES: Deben tenerse en cuenta las características de cada región particular de un país cuando se ejecutan medidas preventivas del sobrepeso y la obesidad, especialmente en las regiones muy pobres y en desarrollo, como el valle de Jequitinhonha en Brasil. Las medidas que se adopten deben considerar una intervención en varios niveles que incluya a la familia, la escuela y el entorno físico.

Ab initio calculations of structural evolution and conductance of benzene-1,4-dithiol on gold leads.

By performing ab initio density functional theory (DFT) calculations and electronic transport simulations based on the DFT nonequilibrium Green's functions method we investigate how the conformational changes of a benzene-1,4-dithiol molecule bonded to gold affect the molecular transport as the electrodes are separated from each other. In particular we consider the full evolution of the stretching process until the junction breaking point and compare results obtained with a standard semilocal exchange and correlation functional to those computed with a self-interaction corrected method. We conclude that the inclusion of self-interaction corrections is fundamental for describing both the molecule conductance and its stability against conformational fluctuations.

Impacto de fatores sociodemográficos e comportamentais na prevalência de sobrepeso e obesidade de escolares / Impact of sociodemographic and behavioral factors on the prevalence of overweight and obesity in schoolchildren

O estudo analisou o impacto de fatores sociodemográficos e comportamentais na prevalência de sobrepeso e obesidade em amostra representativa de escolares de Montes Claros, Minas Gerais, Brasil. A amostra foi constituída por 2849 sujeitos (1457 moças e 1392 rapazes), com idades entre 6 e 18 anos. Sobrepeso e obesidade foram definidos mediante o índice de massa corporal, adotando-se pontos-de-corte para gênero e idade sugeridos pela International Obesity Task Force (IOFT). As prevalências nos diferentes estratos associados aos fatores sociodemográficos e comportamentais foram comparadas por intermédio do cálculo de regressão logística, utilizando-se odds ratios ajustadas. Entre as moças, as prevalências de sobrepeso e obesidade encontradas foram de 19,7% e 4,8%, respectivamente, enquanto entre os rapazes, 14,7% e 2,8%. Os resultados encontrados mostram que, emboraas prevalências do sobrepeso e da obesidade sejam comparáveis com estimativas observadas em outras regiões brasileiras e menores que as encontradas em regiões mais industrializadas, a proporção de escolares que apresentaram sobrepeso e são obesos é particularmente preocupante. Os principais fatores sociodemográficos e comportamentais identificados na ocorrência do sobrepeso e da obesidade foram classe econômica, escolaridade dos pais, número de irmãos, tipo de alimentação na escola, distância e meio de transporte entre a casa e a escola, realização de trabalho remunerado e tipo de atividade no lazer e no tempolivre. Os dados mostram que existe urgente necessidade de implementar programas de intervenção educacional direcionados à promoção da prática de atividade física e de hábitos dietéticos adequados.

This study analyzed the impact of sociodemographic and behavioral factors on the prevalence of overweight and obesity in a representative sample of schoolchildren from Montes Claros, Minas Gerais, Brazil. The sample consisted of 2849 children and adolescents (1457girls and 1392 boys), ranging in age from 6 to 18 years. Overweight and obesity were defined based on body mass index according to the cut-off values for gender and age suggested by the International Obesity Task Force (IOTF). The prevalence rates in the different strata associated with sociodemographic and behavioral factors were compared by logistic regression using adjusted odds ratios. The prevalence of overweight and obesity was 19.7% and 4.8%, respectively, among girls, and 14.7% and 2.8% among boys. The results show that, although the prevalenceof overweight and obesity is similar to estimates observed in other Brazilian regions and smaller than those found in more industrialized areas, the proportion of schoolchildren who presented overweight and obesity is a matter of concern. The main sociodemographic and behavioralfactors associated with the occurrence of overweight were economic status, educational level of the parents, number of siblings, school menu, distance and means of transportation between home and school, paid work, and leisure-time activity. The data show an urgent need for theimplementation of educational intervention programs designed to promote physical activity and adequate dietary habits.

Design of a three-dimensional hand/forearm model to apply computational fluid dynamics

The purpose of this study was to develop a three-dimensional digital model of a human hand and forearm to apply Computational Fluid Dynamics to propulsion analysis in swimming. Computer tomography scans of the hand and forearm of an Olympic swimmer were applied. The data were converted, using image processing techniques, into relevant coordinate input, which could be used in Computational Fluid Dynamics software. From that analysis, it was possible to verify an almost perfect agreement between the true human segment and the digital model. This technique could be used as a means to overcome the difficulties in developing a true three-dimensional model of a specific segment of the human body. Additionally, it could be used to improve the use of Computational Fluid Dynamics generally in sports and specifically in swimming studies, decreasing the gap between the experimental and the computational data.

O objetivo do presente estudo foi desenvolver um modelo digital tridimensional de uma mão e um antebraço humano para aplicar a Dinâmica Computacional de Fluidos ao estudo da propulsão em natação. Foram aplicados procedimentos computorizados de tomografia axial na mão e antebraço de um nadador Olímpico. Através de técnicas de processamento de imagem, os dados foram convertidos em coordenadas tridimensionais, que podem ser utilizadas em programas de simulação computacional. Através dos resultados encontrados, foi possível verificar uma semelhança quase perfeita entre o segmento humano e o modelo digital. Esta técnica pode ser utilizada como uma forma de ultrapassar as dificuldades em desenvolver um modelo digital tridimensional de um segmento específico do corpo humano. Complementarmente, pode ser bastante útil na melhoria da utilização da Dinâmica Computacional de Fluidos no Desporto, de uma forma geral, e, mais especificamente, nos estudos em natação, diminuindo a diferença entre a investigação experimental e a investigação computacional.

Regulation of human umbilical artery contractility by different serotonin and histamine receptors.

We studied the role of several serotonin (5-HT) and histamine receptors in the regulation of human umbilical artery (HUA) contractility. Among the 5-HT agonists used, only the 5-HT( 2A) and 5HT(1B/D) agonists contracts HUA. The 5-HT-induced contractions were fully inhibited by ketanserin (5-HT(2A) antagonist). The 5-HT( 7)-activation also relaxes and increases intracellular cyclic adenosine monophosphate (cAMP). Among the histamine receptor agonists, only betahistine (H(1) agonist) induced significant contractile effect. Histamine-induced contraction was partially relaxed by pyrilamine (H(1) antagonist). Betahistine-induced contraction was partially blocked by dimaprit (H( 2) agonist) and by the H(3) agonist when a low concentration of forskolin is present. Both, H(2) and H(3) agonists increased the cAMP intracellular levels in HUA smooth muscle. These findings show that in HUA, 5-HT(2A)- and 5-HT(1B/1D)-activation lead to vasoconstriction and 5-HT(7)-activation induces vasorelaxation. Concerning histamine receptors, H(1)-activation induces contraction and H(2)- and H(3)-activation lead to vasorelaxation.