A prática de modalidades desportivas por jovens adolescentes

Este estudo teve como objectivo verificar quais as modalidades desportivas mais praticadas pelos jovens após o término das suas actividades lectivas e verificar se existia relação entre a prática de modalidades desportivas e o sexo, classe etária e IMC (Índice de Massa Corporal). Para o efeito, foi levado a cabo um estudo transversal que teve como base a aplicação de um questionário a alunos que, no ano lectivo 2008/2009, frequentavam o 2º e 3º ciclo do ensino básico no Concelho de Bragança. Na edição e tratamento dos dados foi utilizado o SPSS 16.0 (Statistical Package for Social Sciences). Através de uma análise descritiva dos resultados fez-se a caracterização da amostra. Posteriormente, recorreu-se à análise bivariada, designadamente, ao uso do Teste do Qui-quadrado (χ2) para verificar se a prática de modalidades desportivas está ou não relacionada com o sexo, a classe etária e o IMC. Participaram neste estudo 536 jovens (301 rapazes e 235 raparigas) com idades compreendidas entre os 10 e os 18 anos. Pela análise dos resultados pode verificar-se que as modalidades desportivas mais praticadas foram o “futebol”, o “basquetebol” e o “BTT”. Constatou-se que existe uma relação entre a prática de modalidades desportivas e as variáveis género, idade e IMC. Apenas a modalidade desportiva “dança” é preferida pelas raparigas enquanto modalidades tais como o “futebol”, o “skate”, o “rappel”, a “escalada”, o “atletismo”, o “ténis de mesa” e as “artes marciais” são praticadas em maior número por rapazes. No que diz respeito à idade, constatou-se que o “basquetebol”, a “patinagem”, o “hóquei” e a “ginástica” são modalidades, normalmente, desenvolvidas pelos mais jovens (10-13 anos). Por fim, verificou-se existir uma relação entre o IMC e as modalidades desportivas, “futebol”, “BTT” e “atletismo”. Constatou-se, ainda, que os inquiridos com peso normo-ponderal são os que praticam mais estas modalidades

A prática de modalidades desportivas por jovens adolescentes

Este estudo teve como objectivo verificar quais as modalidades desportivas mais praticadas pelos jovens após o término das suas actividades lectivas e verificar se existia relação entre a prática de modalidades desportivas e o sexo, classe etária e IMC (Índice de Massa Corporal). Para o efeito, foi levado a cabo um estudo transversal que teve como base a aplicação de um questionário a alunos que, no ano lectivo 2008/2009, frequentavam o 2º e 3º ciclo do ensino básico no Concelho de Bragança. Na edição e tratamento dos dados foi utilizado o SPSS 16.0 (Statistical Package for Social Sciences). Através de uma análise descritiva dos resultados fez-se a caracterização da amostra. Posteriormente, recorreu-se à análise bivariada, designadamente, ao uso do Teste do Qui-quadrado (χ2) para verificar se a prática de modalidades desportivas está ou não relacionada com o sexo, a classe etária e o IMC. Participaram neste estudo 536 jovens (301 rapazes e 235 raparigas) com idades compreendidas entre os 10 e os 18 anos. Pela análise dos resultados pode verificar-se que as modalidades desportivas mais praticadas foram o “futebol”, o “basquetebol” e o “BTT”. Constatou-se que existe uma relação entre a prática de modalidades desportivas e as variáveis género, idade e IMC. Apenas a modalidade desportiva “dança” é preferida pelas raparigas enquanto modalidades tais como o “futebol”, o “skate”, o “rappel”, a “escalada”, o “atletismo”, o “ténis de mesa” e as “artes marciais” são praticadas em maior número por rapazes. No que diz respeito à idade, constatou-se que o “basquetebol”, a “patinagem”, o “hóquei” e a “ginástica” são modalidades, normalmente, desenvolvidas pelos mais jovens (10-13 anos). Por fim, verificou-se existir uma relação entre o IMC e as modalidades desportivas, “futebol”, “BTT” e “atletismo”. Constatou-se, ainda, que os inquiridos com peso normo-ponderal são os que praticam mais estas modalidades

Produção de adsorventes de carbono a partir de desperdícios de madeira de Teca por ativação física e sua aplicação na remoção de pesticidas

A utilização de pesticidas na área agrícola está bastante disseminada, com particular relevo na proteção das culturas. Associadas às inúmeras vantagens existe um número elevado de desvantagens, com destaque para a produção de resíduos que são gerados inevitavelmente aquando da sua aplicação e que perduram, por vezes, por longos períodos de tempo nos ecossistemas, afetando todas as outras espécies animais e vegetais que nele coabitam, com particular incidência para o homem

Valorisation of Teak Sawdust by the Production of Activated Carbon

The valorisation of wood wastes by the production of added value materials is one of the possible strategies to expand the income sources and increase the economic activity. This approach is very important in particular for the developing countries like East Timor

Adsorption of MCPA, 2,4-D and diuron onto activated carbons from wood

Activated carbon adsorbents were produced from particleboard and medium-density fiberboard, industry originated wastes, without value added applications. These materials were characterized, showing a well-developed microporous structure reaching 0.58 cm3/g, and afterwards, their potential application for the removal of phenoxy acetic acids and substituted urea herbicide was evaluated. Studies in liquid phase were conducted in 2,4-dichlorophenoxy acetic acid (2,4-D), 4-chloro-2-methylphenoxy acetic acid (MCPA) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron), being the obtained data linearized using the Langmuir and Freundlich equations. Results indicated high removal capabilities for the adsorptives in study, reaching 0.97, 1.37 and 1.87 mmol/g for diuron, 2,4-D, and MCPA respectively, allowing the conclusion that these materials should be studied further, having in mind real life applications. © 2017 Portuguese Society of Materials (SPM). Published by Elsevier España, S.L.U.. All rights reserved. Keywords: Activated carbon; adsorption; pesticides; monolith wood

Designing Activated Carbons from Natural and Synthetic Raw Materials for Pollutants Adsorption

Over the last decades the literature has shown the possibility of producing activated carbons (AC) from a wide variety of raw materials, and to use them as one of the most environment-friendly solutions for waste disposal [1]. Simultaneously, it has been shown that the adsorption of pollutants from different sources by activated carbons is one of the most efficient techniques for remediating or solving this kind of problem [2]. In this context, phenolic compounds represent one of the most important classes of pollutant present in the environment [3]. In this perspective, we present a study involving the production of AC from cork (Quercus suber L.), PEEK (polyetheretherketone) wastes or granulated recycled PET (polyethyleneterephthalate) and their applicability for the adsorption of phenolic compounds from the liquid phase. All samples were characterised in relation to their structural properties and chemical composition, by different techniques, including nitrogen adsorption at 77 K, elemental analysis (C, H, N, O and S) and point of zero charge (PZC). The activated carbons produced demonstrated high adsorption capacities both in the gas and liquid phase as exemplified by N2 and phenolic compounds adsorption experiments. Based on the structural and chemical properties, and on the kinetic and equilibrium studies of liquid phase adsorption, it is possible to conclude that it is the porous volume of the ACs that predominantly controls the process of phenolic compounds adsorption

Economic development and changes in human resource management in a sustainable agricultural sector: recent evidence from Brazilian sugar–alcohol companies

This research received no external funding.Economic development causes significant changes in the innovative processes of resource management. The purpose of this article is to discuss the sustainability of resource management in sugar–alcohol companies operating in the most productive areas of Brazil and to analyze the profile of the companies in the sector in terms of innovation and adherence to practices of human resource management. The methodological procedures were based on qualitative research. Data collection was directed toward the population of companies in the sector of cane brandy production, having as the main criteria representativeness of human resource management and to be active. The results indicate that human management tends to be traditional in spite of several current economic challenges. The conclusions also highlight that the most highly mechanized companies are those that have adhered to strategic policies and practices, and that the traditional model of human management prevails in more than 70% of companies.(undefined

Changes of food habits in school-aged children and adolescents

O objetivo desta investigação foi conhecer as diferenças no padrão alimentar de estudantes que frequentam diferentes ciclos de estudo do ensino básico (2.º e 3.º ciclos do ensino básico). A amostra foi constituída por 529 adolescentes com13,32 (±1,59) anos, de numa escola pública portuguesa. A obesidade foi calculada através do IMC. Para recolher informação do padrão alimentar aplicou-se um questionário. O teste do Qui-Quadrado utilizou-se na comparação entre grupos. A prevalência de excesso de peso/obesidade foi de 22,8%. Verificou-se uma maior prevalência de excesso de peso/obesidade no 2.º ciclo (27,9% versus 18,9%, p=.015). Os estudantes mais velhos saltam mais refeições (primeiro-almoço p=.000, almoço p=.009, jantar p=.015), bebem mais refrigerantes (p=.046) e bebidas alcoólicas (p=.001). Quanto ao consumo de doces, fruta, vegetais e leite, não se observam diferenças estatisticamente significativas, entre os ciclos. Concluindo, verifica-se uma degradação do padrão alimentar na passagem do 2.º para o 3.º ciclo do ensino básico.The aim of this study is to compare the food pattern of students who attend different school grades. The sample consisted of 529 adolescents with 13.32(±1.59) years, from a Portuguese public school. Obesity was calculated using BMI. A questionnaire was applied to collect information on the food pattern. The chi-square test was used to compare the two groups. The overall prevalence of overweight + obesity was 22.8%. The group that attended 5th and 6th grades present a higher prevalence of overweight +obesity in (27.9% versus 18.9%, p=.015). Older students skip more meals (breakfast p=.000, lunch p=.009, dinner p=.015), drink more soft drinks (p=.046) and alcoholic drinks (p=.001). Regarding the consumption of sweets, fruit, vegetables and milk, there are no statistically significant differences between the grades. In conclusion, there is a trend of an unhealthy food pattern from the 5th and 6th grades to the 7th, 8th and 9th grades.info:eu-repo/semantics/publishedVersio

Evaluation of invasive Acacia species compost as alternative horticultural organic substrates

The physical and chemical characteristics of composts of invasive Acacia longifolia and Acacia melanoxylon shrubs were evaluated to identify compost limitations as a substrate component. The bulk density was 85% of the total volume. Air capacity, the easily available water and buffering capacity were also within acceptable recommended values for horticultural substrates. With increased composting time the physical characteristics of the composts improved, but the same was not true for chemical characteristics. It is recommended to use these acacia composts in mixtures with peat which increases the content of organic matter and the C/N ratio, and decreases the pH and the electrical conductivity, of the final substrates

Textural Development of Activated Carbon Prepared from Recycled PET With Different Chemical Activation Agents

In this work a series of microporous activated carbons, with different burn offs, was prepared from recycled PET provided by Selenis (Portalegre-Portugal). These AC were prepared by chemical activation with KOH, NaOH and H3PO4, and carbonised under a N2 flow of 85cm3min-1 between 873 and 1273K. The carbonised samples were then cooled and successively washed until the washable solutions achieved a pH around 7.0, afterwards these were dried at 110ºC. All adsorbents were characterised by the adsorption of N2 at 77K and the pHpcz and the elemental analyse were determined. First, with all activation agents when the carbonization temperature increased up to 723K, the carbonization yield increased. With NaOH, the carbonization yield varied from 8 to 31% and the optimal ratio of NaOH/PET was less than with KOH. The pore size was in all cases larger (between 1.15 and 2.4 nm) when compared with the AC obtained with the other activating agents. On the other hand, the AC prepared with H3PO4 present the narrowest pore size (between 0.76 and 0.83 nm) and the highest micropore volume (0.34 cm3 g-1) was obtained with a ratio of H3PO4/PET =0.75. All samples prepared with H3PO4 present an acidic point of zero charge, between 2.3 and 4.2. AC prepared by chemical activation with KOH, when the carbonisation temperature increased from 873 to 1173 K the yield decreased from 33.5 % to 23%. While at 1273K, the carbonization was too extensive, so this temperature was considered too high, as we only obtained ash. Fig.1 presents the N2 adsorption isotherms on some of the AC activated with KOH at different temperatures, with a ratio of KOH/PET=2. All isotherms are type I typical of microporous carbons. At lower temperatures, the initial steep increase in adsorption is followed by an almost horizontal plateau. However at 1173K the extent of the opening of the knee shows an obvious variation, which generally increases with the pore enlargement