Estudos sobre a nutrição mineral do arroz: X. marcha de absorção de micronutrientes pela variedade IAC-25

The uptake of micronutrients (B, Cu, Fe, Mn and Zn) by the variety IAC-25 in various phases of its development was studied, the plants being grown in nutrient solution, Main conclusions were the following: (a) only two variables, namely dry matter production an Fe accumulation, showed a tendency to level off as the plants complete their life cycle; (b) indication of internal redistribution was observed in the case of Fe and Mn; (c) maximum rate of uptake, was well as of dry matter production took place in the period which goes from tillering to grain filling.Em condições controladas estudaram-se: acumulação de micronutrientes e produção de materia seca pela variedade de arroz IAC-25. A curva que descreve a produção de matéria seca total em função do tempo apresentou a tendência a sigmóide. Com respeito a acumulação global de micronutrientes, entretanto, o mesmo foi observado somente no caso do ferro

The training of coaching skills: An implementation study

Contains fulltext : 28715.pdf (publisher's version ) (Open Access)In this study, the implementation effects of a programme for the training of coaching skills with Dutch school counsellors are described. These school counsellors are expected to provide help and support to primary school teachers. Coaching is a form of in-class support intended to provide teachers with feedback on their own functioning and thereby stimulate self-reflection and self-analysis in order to improve instructional effectiveness. To assist school counsellors in their attempts to coach teachers, a training programme was designed: 'The school counsellor as coach'. A quasi-experimental, treatment-control group investigation was then set up to test the effects of this programme. Based on the pre- and post-training ratings of coaching conferences, a significant treatment effect was found for the coaching skills concerned with the development of autonomy (empowerment), feedback, and purposefulness. The pre- and posttraining ratings from coached teachers showed no significant treatment effects. This was because the teachers were not accustomed to in-class assistance and thus rated the coaching skills of the school counsellors quite favourably even at pre-test

Estudos sobre a nutrição mineral do arroz: VIII. marcha de absorção de macronutrientes na variedade IAC-25

Rice plants, IAC 25 variety, were grown in nutrient solution; samples were taken for analysis at different intervals, namely 21, 50, 79, 91 and 112 days after germination. Main conclusions were the following: (1) both dry matter production and accumulation of macronutrients as a function of time were described by typical sigmoide curves; (2) in the period between the second and third sampling the rate for both processes reached maximum values; (3) dilution effects were observed in the content of all the elements except Ca; (4) Ca also was the only macronutrien which does not seem to be translocated from leaves for grainfiling.Foram estudadas, em condições controladas, a acumulação de matéria seca e a acumulação de macronutrientes pela variedade de arroz IAC 25. Como regra verificou-se que a acumulação de matéria seca e de macronutrientes obedeceu a sigmoides típicas, ambos os processos ocorendo com maior velocidade no período aproximado de 5O-9O dias após a germinação