Validation of a self-perceived media competence instrument for pre-service teachers / Validación de un instrumento de autopercepción de competencia mediática para docentes en formación

Abstract

Key to guaranteeing the fundamental human rights of freedom of expression and information is the development of media competence, particularly in schools. Training teachers in the area of media competence is particularly important for developing these skills in the broader citizenry. In order to provide educators and educational policymakers with a useful diagnostic tool, we have designed a self-perception questionnaire. The questionnaire was applied to a sample of Peruvian education students (N = 501). On the one hand, the results confirm the construct’s coherence, validity and instrumental reliability. On the other hand, they allow us to propose a theoretically based update to the way in which this construct is interpreted and applied, confirming the multidimensionality of media competence. Finally, we use this empirical evidence to discuss the integral, transversal and ecological status of media competence.     

Physiological responses in different intensities of resistance exercise – Critical load and the effects of aging process

Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO₂) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La^?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.     

Jump higher,run faster: effects of diversified sport participation on talent identification and selection in youth basketball

ABSTRACT

The aims of this study were to examine the medium-term effects of previous experiences during early stages of sport development on physical capacities of under-13 (U-13) talented basketball players and, to identify variables that discriminated under-14 (U-14) national team training camp selection. Anthropometrical and physical measurements were collected during a basketball training camp. Previous sport experiences (6–10 years), maturity offset, power outputs for jumping and sprinting were determined. A cluster analysis was used to allocate the subjects according to their different levels of sport experiences (more specialized vs. less specialized) to allow creating a dummy variable for the subsequent analysis of the physical variables. A stepwise discriminant analysis was computed to identify the construct that best classifies selected and non-selected players for U-14 national team training camp. The less specialized group outscored more specialized in all physical parameters, irrespectively of gender. The Abalakov Jump Peak Power and Predicted Adult Height (PAH) could successfully discriminate selected from non-selected players for U-14 national team training camp in boys and PAHin girls. The diversified and non-specific sport stimulus during early ages seem to be determinant to the acquisition and development of fundamental movement skills of talented basketball players.     

On the value of project safeguards: Embedding real options in complex products and systems

This study defines a project safeguard as the design and physical development work needed to ensure, or enhance, the embedding of a real option in complex products and systems (CoPS). Safeguards operationalize optionlike strategic thinking at implementation. I examine safeguarding investments through an in-depth multiple-case study of 12 options embedded across 5 projects encompassed by an airport expansion programme. This includes options to phase out delivery (stage-option), grow capacity (growth-option), and switch operational regime (switch-option). Passive safeguards only involve design work, whereas active safeguards involve both design and physical execution. The analysis shows how the confluence between the uncertainty of option exercising and the modularity of the relevant functional elements in relation to the CoPS architecture affects the attractiveness of safeguarding. High uncertainty makes safeguarding less attractive as it can lead to sunk costs that may not pay off over the CoPS operating life. Conversely, high modularity increases the attractiveness of safeguarding because (1) safeguards can be limited to marginal investments at the interfaces between the functional elements with other CoPS subsystems, and (2) the stability of modular design rules increases the likelihood that safeguards remain valid over time. Safeguards build options into integrative CoPS. This flexibility and redundancy makes them resilient to change stemming from option exercising if uncertainties resolve favourably in the future.     

Competition and diversity in higher education: an empirical approach to specialization patterns of Portuguese institutions

The expansion of higher education systems has often been associated with the need for increasing diversification, namely at the program level, based on the pressures to adapt more general programmes to a more diverse student population and multiple regional, social, and economic needs. This paper explores empirically the question of programme diversity by drawing on the Portuguese higher education’ experience, which presented massive expansion during the last decades and significant institutional competition in recent years. The study provides a longitudinal approach and analyzes in detail the evolution of diversification and specialization of the public and private sectors, as well as the university and polytechnic subsectors. The analysis aims at helping to illustrate the relevance of analysing diversity from an empirical point of view and its contribution to our understanding of the complex relationships between competition and diversity in contemporary higher education.     

Three-dimensional kinematics of competitive and recreational cyclists across different workloads during cycling

Although the link between sagittal plane motion and exercise intensity has been highlighted, no study assessed if different workloads lead to changes in three-dimensional cycling kinematics. This study compared three-dimensional joint and segment kinematics between competitive and recreational road cyclists across different workloads. Twenty-four road male cyclists (12 competitive and 12 recreational) underwent an incremental workload test to determine aerobic peak power output. In a following session, cyclists performed four trials at sub-maximal workloads (65, 75, 85 and 95% of their aerobic peak power output) at 90?rpm of pedalling cadence. Mean hip adduction, thigh rotation, shank rotation, pelvis inclination (latero-lateral and anterior–posterior), spine inclination and rotation were computed at the power section of the crank cycle (12 o'clock to 6 o'clock crank positions) using three-dimensional kinematics. Greater lateral spine inclination (p?p?p?相似文献   

Marine Aerosol Weathering of Mediterranean Calcarenite Stone: Durability of Ethyl Silicate,Nano Ca(OH)2, Nano SiO2, and Nanostructured Consolidating Products

ABSTRACT

Calcarenite stone samples from a historic building (Bizerte, Tunisia) were collected and treated under different environmental conditions with several consolidating products: alkoxysilane (ethyl silicate), a surfactant-templated novel sol–gel, Ca(OH)₂, and SiO₂ nanoparticles. These were subjected to marine aerosol accelerated aging cycles and studied by several non-destructive tests and techniques to assess the stability of the products. Results show that weathering caused by salt crystallization is not inhibited but it is slowed down due to the enhancement of superficial mechanical properties (surface cohesion and micro-hardness) achieved after one month of treatments application. A high or low relative humidity of the consolidation environment significantly affects the final mechanical and aesthetical physical properties and therefore conditions the durability of the treated substrates, even producing higher damage than observed in the blank specimens, depending on the product.