Scientific literacy and informal science teaching

Two stages in research on scientific literary are identified: a composite saturation stage in which definitions covered all objects of science education and a stage where researchers focused on small manageable portions of scientific literary. Initial and continuous scientific literacy research in which the focus is on cognitive preference for science and informal science teaching is described. Underlying cognitive preference is a value preference for science. Three interdependent but clearly distinguishable forms of science teaching, formal, nonformal and informal, are described. Informal science teaching is identified as a condition for and an outcome of scientific literacy.     

The relationship between peak height velocity and physical performance in youth soccer players

Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time.     

The electron mechanics of induction acceleration

The radial and axial motions of electrons in the betatron are described by means of a potential function of forces. Previously reported conditions of equilibrium, stability and damping of oscillations are derived for the region of parabolic variation of the potential. Extension of the analysis to, non-parabolic regions gives an account of the injection in conventional instruments in better agreement with experiment, particularly in regard to higher voltages of injection.Space charge limitations are discussed with the help of the Laplacian of the potential of forces.By means of an additional radial electric field electrons can be introduced as in the magnetron, without any asymmetry inherent in the conventional betatron circumferential injector. The analysis of the conditions of equilibrium and stability, greatly facilitated in this case by the notion of potential, shows that no substantial improvement in space charge limitations can be expected and that the required variations between the flux linking the electron orbits and the magnetic and electric fields at the orbits are difficult to realize on account of their complexity and narrow tolerances. The X-ray output of a small experimental double yoke instrument was measured by a phototube multiplier viewing an irradiated fluorescent screen and gave evidence of multiple group electron capture.     

Juggling competing activities: academic staff as doctoral candidates

ABSTRACT

This article explores the experiences of a group of established academic staff in New Zealand and the UK, as they undertake a doctorate in their home institutions. Our interest is in how individuals negotiate this dual status from a cultural-historical activity theory (CHAT) stance that explores how rules, tools, community and divisions of labour, and interacting activity systems, shape doctoral experiences. The focus in this article, having analysed their detailed narrative accounts, is on how academics experience three interdependent activity systems: those surrounding the thesis, the institutional context, and the home-life spheres. Issues related to time, workload and supervision issues, variability in collegial support and impact on personal priorities and time emerged. There is a range of particularities – from easy access to resources/supervisors to inflexible institutional regulations – applicable to this group of doctoral candidates. Negotiating life as an academic with concurrent doctoral candidature provides positive outcomes in terms of teaching, research confidence and general personal and professional development. However, a range of difficulties can also be encountered, particularly in relation to personal and professional relationships, and workload management.