Una introducción a la dinámica no lineal en enseñanza Secundaria

An interesting study on an approach to Physics teaching of an introduction to non-linear dynamics, at a basic level, is presented here. This study, framed on the constructivist theory of learning has led to the actual possibility of explaining in secondary clasrooms the elementary foundations of this outstanding area in modern physics. An initial exploration of the prior beliefs of pupils about mechanics and predictibility constituted the base of this attempt

Enseñanza por cambio conceptual : de la física clásica a la relatividad

In this article the possibility of learning through conceptual change and the best way to achieve this aim, are discussed. This teaching needs to have certain specific features and ensure that the debate in the classroom is focused on the explicit ideas of the students, whose conceptual difficulties must be taken into account with considerable care. To obtain those results, we are to give critical importance to the explanation and justification of ideas, debates must be metacognitive and professors should share discussion in an active and diversified role. One example of this way of teaching is introduced in this article concerning the conceptual change required to pass from classical to relativistic physics

Una nueva propuesta didáctica para la enseñanza de la relatividad en el Bachillerato

The great importance that has been given to teaching the theory of Relativity in intermediate levels by the new plans of secondary education, is often discouraged by the erroneous treatment of all these topics in the usual didactic formulations. So, in this work we dare to suggest a new point of view which is more accurately attached to the real and original spirit of the genuine Relativity. Our proposal lies on recovering in teaching the ideas of space-time and geometric representations introduced by Minkowski

OARSI year in review 2023:Rehabilitation and outcomes

Objective: We systematically reviewed the literature to identify comparative studies of core treatments (exercise, education, or weight management), adjunct treatments (e.g. electrotherapeutical modalities, bracing), or multimodal treatments (core plus other treatments), for treating osteoarthritis (OA) complaints, published between 1 March 2022 and 1 March 2023. Design: We searched three electronic databases for peer-reviewed comparative studies evaluating core treatments, adjunct treatments, or multimodal treatments for OA affecting any joint, in comparison to other OA treatments. Two authors independently screened records. Methodological quality was assessed using the Physiotherapy Evidence Database (PEDro) scale. A narrative synthesis focusing on pain and function outcomes was performed in studies with a mean sample size of at least 46 participants per treatment arm. Results: 33 publications (28 studies), 82% with PEDro ratings of good or excellent, were eligible for narrative synthesis: 23 studies evaluated knee OA; one knee OA or chronic low back pain; two knee or hip OA; one hip OA only; and one thumb OA. No studies identified a dose, duration or type of exercise that resulted in better pain or function outcomes. Core treatments generally showed modest benefits compared to no or minimal intervention controls. Conclusions: Rehabilitation research continues to be focused on the knee. Most studies are not adequately powered to assess pain efficacy. Further work is needed to better account for contextual effects, identify treatment responder characteristics, understand treatment mechanisms, and implement guideline care.</p

Influence of pulse crops on arbuscular mycorrhizal fungi in a durum-based cropping system

Non-Peer ReviewedPulses are an important component in crop rotations in southern Saskatchewan. Besides their capability to fix nitrogen, pulse crops establish a symbiotic relationship with arbuscular mycorrhizal fungi, which have been shown to increase nutrient and water uptake through hyphal extensions in the soil. This 2 year study is designed to evaluate the impact of pulses in crop rotations on the biodiversity of AMF communities and their dynamics. Plant N and P uptake and the available soil N and P pools under a durum crop are also measured to assess if there is any correlation with AMF communities. The sampling and analysis is completed on the durum phase of the rotation with preceding crops of pea, lentil, chickpea, canola and durum. The final results will be explained by: (1) the size, nature, and physiological state of the soil microbial community and (2) the nature of the preceding crop residues. Preliminary results from the 2004 season indicate that higher plant P uptake is related to AMF colonization, while no significant change was detected in the soil N and P pools

The effect of long-term application of P fertilizer on soil grown forage plants

Non-Peer ReviewedPhosphorus (P) fertilization does not always increase crop yields but the repeated use of P may modify the biological properties of soils. The objective of the present study, therefore, was to investigate the effect of long term applications of P fertilizer on soil biological properties. We used an experimental site located in Swift Current in which different amounts of P (0, 20 and 40 kg P2O5 ha-1) were applied annually for the past 8 years on alfalfa and alfalfa-Russian wild rye hay crops. Our hypothesis was that repeated application of P influences soil microbial biomass and various soil enzymes. Microbial biomass C in the 0-7.5 cm soil layer was determined by fumigation-extraction at each of three harvest dates, and dehydrogenase, acid phosphatase and urease activities were assayed. Application of P to soil increased soil available P, dissolved organic C and available NO3-N, but did not significantly affect crop yields or soil microbial biomass C. Arbuscular mycorrhizal colonization of crop roots, and dehydrogenase and urease activities were decreased, suggesting that P reduced soil microbial activity. Acid phosphatase activity remained unchanged with P fertilization, suggesting that P availability was not limiting in these systems. While 8 years of application of P had little effect on hay yields, it generally reduced the activity of the soil microbial biomass

An evaluation of the vacuum/pressure moisturization technique of seed grains and oilseeds

Non-Peer Reviewe