3 resultados para training of young teachers

em Repositório Científico da Universidade de Évora - Portugal


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SHORT-TERM EFFECTS OF SALINITY ON SOME PHYSIOLOGICAL PARAMETERS OF YOUNG OLIVE TREES OF ARBEQUINA, COBRANÇOSA AND GALEGA VARIETIES Ana Elisa Rato1,4, Renato Coelho1, Margarida Vaz1, Teresa Carola2, Dália Barbosa2, Nádia Silva1, José dos Santos2, Lourenço Machado2, João Godinho2, Luzia Ruas2, Margarida Barradas2, Hernani Pereira2, Sara Porfírio4 1 ICAAM, Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal 2 Master students, Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal 3 Ph.D. student, Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal 4 aerato@uevora.pt Due to the desertification in some regions, the interest in plant’s tolerance to salinity has been increasing, as this response is determining for plant survival in stress conditions. This work reports the investigation of tolerance to salt in two year-old olive trees (Olea europaea L.) of three varieties, Arbequina, Cobrançosa and Galega vulgar. Plants were grown in 10 L plastic pots containing approximately 9 Kg of a sandy granitic soil, on a greenhouse. For 3 months (from the beginning of February to the end of April 2012), they were subjected to three levels of salinity in the irrigation water, 0 mM, 80 mM and 200 mM NaCl (6 plants per salinity level in a total of 18 plants of each variety),. Stomatal conductance (gs) and relative leaf chlorophyll content were assessed on each plant in February, March and April. Mid-day leaf water potential () and soil salinity were measured at the end of the experiment (April). On average, concerning all treatments and dates of determination, stomatal conductance of Arbequina and Galega vulgar was quite similar, around 40 mmol m-2 s-1, but Cobrançosa had a value of gs 36% higher, almost 50% higher (61 mmol m-2 s-1) when compared with the controls (0 mM salt) of the other two varieties. In percentage of controls, there was little difference in gs between varieties and between salinities during February and March. In contrast, in April, after about 90 days of exposure to salt, there was a clear decrease in gs with salt irrigation, proportional to salt concentration. Compared with controls, plants irrigated with 200 mM salt showed around 80% (Arbequina) or 85% (Cobrançosa and Galega vulgar) decrease in gs. Chlorophyll content of leaves showed less than 5% difference between varieties on the average of all treatments and dates of determination. During the course of this experiment, the salinity levels used did not show any relevant effect on chlorophyll content. Overall, at the end of the experimental period (April), leaf water potential () at midday was significantly higher in Cobrançosa (-1,4 MPa) than in Galega vulgar (-1,7 MPa) or Arbequina (-1,8 MPa), and salt decreased  of control plants (-1,25 MPa) by an average 30% (with 80 mM) and 65% (with 200 mM). At the end of the experiment, salinity in the soil irrigated with 0 mM, 80 mM or 200 mM NaCl was, on average of all varieties, 0,2 mS, 1,0 mS or 2,0 mS, respectively. Soil salinity was quite similar in Arbequina and Galega vulgar but about 35% lower in the pots of Cobrançosa, on average of all salt-irrigation levels. Plants of Cobrançosa had higher stomatal conductance, however they showed higher water potential and lower salinity in the soil. These apparently contradictory results seem to suggest that Cobrançosa responds to salt differently from the other two varieties. This issue needs further investigation.

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The aim of this study was to compute a swimming performance confirmatory model based on biomechanical parameters. The sample included 100 young swimmers (overall: 12.3 ± 0.74 years; 49 boys: 12.5 ± 0.76 years; 51 girls: 12.2 ± 0.71 years; both genders in Tanner stages 1–2 by self-report) participating on a regular basis in regional and national-level events. The 100 m freestyle event was chosen as the performance indicator. Anthropometric (arm span), strength (throwing velocity), power output (power to overcome drag), kinematic (swimming velocity) and efficiency (propelling efficiency) parameters were measured and included in the model. The path-flow analysis procedure was used to design and compute the model. The anthropometric parameter (arm span) was excluded in the final model, increasing its goodness-of-fit. The final model included the throw velocity, power output, swimming velocity and propelling efficiency. All links were significant between the parameters included, but the throw velocity–power output. The final model was explained by 69% presenting a reasonable adjustment (model’s goodness-of-fit; x2/df = 3.89). This model shows that strength and power output parameters do play a mediator and meaningful role in the young swimmers’ performance.

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Aims: To compare the physical activity, sedentary activity and health-related quality of life (HRQoL) in institutionalized vs. non-institutionalized elderly, and to establish a pattern of relationship and prediction of physical and sedentary activity with physical and mental components of HRQoL. Methods: The sample consisted of 383 elderly with ≥ 75 years old (n=187 institutionalized and n=196 non-institutionalized). Were administered the International Physical Activity Questionnaire (IPAQ) and Short Form 36 Health Survey (SF-36) for evaluated the physical and sedentary activity and HRQoL. Also was used the Mini Mental State Examination (MMSE) as exclusion criteria for cognitive problems in the elderly. Results: Differences between institutionalized and non-institutionalized elderly were found in moderate-intensity activities and walking, a favour of non-institutionalized. The institutionalized elderly remain more minutes in sedentary activity. Also, were observed differences between both groups in physical component of HRQoL, a favour of non-institutionalized elderly. The mental component remained unchanged. The multivariate regression analyses showed that physical activity predicted the physical (8 to 12%) and mental (5 to 8%) components of HRQoL for institutionalized and non-institutionalized elderly. Conclusions: Non-institutionalized elderly were more physically active, spent less time in sedentary activity and showed better perception physical component of HRQoL that institutionalized elderly. An important and encouraging result of this study was that physical activity is a predictor of improved physical and mental component of HRQoL for institutionalized and non-institutionalized elderly.