Orientare gli atteggiamenti dei futuri docenti verso interventi efficaci: ristrutturare misconcezioni e punti di vista didattici ingenui

Orienting the attitudes of future teachers towards effective interventions: Restructuring misconceptions and naïve didactic points of view. The research on the teaching effectiveness and on the behaviour of expert teachers from an evidence based perspective allows today to envisage articulated training models that can accompany students-aspirants or teachers themselves from a preliminary theoretical moment of first familiarization with effective models, to their operational use and up to an evaluation of the improvement obtained on their pupils. A delicate point concerns the gap between the preconceptions on teaching with respect to those of who can be considered «expert teachers». This work takes up previous studies related to the use of a questionnaire, created to evaluate this gap, in order to reduce it by means of feedbacks, before starting the trainee to practical applications to be conducted in the laboratory or in the class. By proposing an iterative version of this tool within university teaching courses, the work also focuses the concordances common to the various applications carried out over the years, that highlight a network of clichés and stereotypes rooted in the school culture, which represents a restraining factor for the adoption of attitudes of greater efficacy

Viable Singularity-Free f(R) Gravity Without a Cosmological Constant

Several authors have argued that self-consistent $f(R)$ gravity models distinct from $\Lambda$CDM are almost ruled out. Confronting such claims, we present a particular two-parameter $f(R)$ model that: (a) is cosmologically viable and distinguishable from $\Lambda$CDM; (b) is compatible with the existence of relativistic stars; (c) is free of singularities of the Ricci scalar during the cosmological evolution and (d) allows the addition of high curvature corrections that could be relevant for inflation.Comment: 4 pages, 3 figures, accepted for publication in Phys. Rev. Let

Cruzando los mallkus. Las migraciones bolivianas pendulares durante las grandes crisis salitreras (1914 - 1933)

Este artículo analiza el proceso migratorio pendular de la población boliviana (especialmente indígena) hacia las salitreras de Tarapacá; destacándose la “gran crisis” de 1930 y años siguientes, analizando el desarraigo del retorno a Bolivia. Se sostiene que a partir del término de la Primera Guerra Mundial se inicia la decadencia del ciclo de expansión del salitre, generando procesos migratorios de atracción y expulsión de mano de obra, donde el drama social producto de la cesantía fue el factor común. En otras palabras, se plantea que la crisis del salitre no surgió en la década de los años treinta, como suele reconocerse en la literatura especializada sobre la industria salitrera, sino a partir de la primera guerra mundial se inicia el proceso de decadencia del mercado mundial del nitrato, siendo la década de los años veinte cuando se define el futuro de esta industria. Se estudia, especialmente a través de la prensa y archivos oficiales, los sistemas de enganche, los flujos de ida y venida de trabajadores bolivianos con sus familias, especialmente durante los años de crisis entre 1914 y 1933, donde el drama de la cesantía afectó a miles de bolivianos que debieron regresar a sus comunidades de origen. Este artículo se enmarca dentro de un análisis histórico que rescata la importancia de la sociedad civil en las relaciones entre países fronterizos, como Bolivia y Chile, fenómeno que la disciplina de las relaciones internacionales denomina acertadamente “paradiplomacia”

Mappe concettuali dinamiche per supportare i processi di e-learning e di valutazione

When technologies enter the learning processes, it is always advisable to analyse the changes they trigger carefully. This is because their effects are difficult to predict and generalize. There are several factors related to the times, ways, status, culture, even digital, of the subjects involved and therefore any statement should derive from careful observations and cautious analysis.This article moves along the line of research traced by a laboratory of the University of Salerno, the laboratory RIMEDI@, using for a further academic year, a technology within a learning environment, the e-Lena platform. In fact, this use derives from a first phase of experimentation from which the results have emerged identified possible future developments. After that, a series of corrective measures have been implemented to proceed now with this second experiment, which is either to confirm or refute the results already obtained and to verify the effectiveness of the changes made. The access to the environment is provided in addition to the classroom teaching, so it assumes a form of support and not a substitute form of in presence teaching. We tried to verify if our enriched online learning environment could stimulate remediation processes between digital and analogic artefacts in students and represent a mean to support automatic evaluation processes. In other words, we would answer the question related about if it favours the development of meaningful learning. The use of this technology was therefore observed and the data collected analysed to be able to synthesize conclusions and outline new objectives in order to move the next steps in research. The results confirm once again that the environment built in e-Lena offers an effective support to students. It takes a significant role both in activating remediation experiences and in automating evaluation processes, so it could encourage the development and the consolidation of learning.Quando le tecnologie “entrano” nei processi di apprendimento, è opportuno analizzare con attenzione i cambiamenti che attivano. Questo perché gli effetti che producono sono difficili da prevedere e da generalizzare. Sono diversi i fattori che interagiscono (tempi, modi, cultura anche digitale dei soggetti coinvolti) e ogni affermazione dovrebbe derivare da osservazioni accurate eanalisi prudenti. Questo articolo si muove lungo una direttrice di ricerca del laboratorio RIMEDI@dell’Università di Salerno nel quale, nell’ultimo triennio, è stato sperimentato ed implementato un ambiente virtuale di apprendimento all’interno della piattaforma e-Lena. L’accesso all’ambiente viene fornito in aggiunta all’insegnamento in aula, quindi assume una forma di supportoe non una forma sostitutiva di insegnamento in presenza. Obiettivo dell’indagine è stato quello di verificare se, e in qual misura, l’ambiente di apprendimento online potesse stimolare negli studenti processi di rimediazione tra artefatti digitali e analogici e rappresentare un mezzo per supportare processi automatici di valutazione. I risultati confermano che l’ambiente costruito in e-Lena offre un supporto efficace agli studenti. Esso assume un ruolo significativo sia nell’attivazione delle esperienze di rimediazione che nell’automazione dei processi di valutazione, in modo da incoraggiare lo sviluppo e il consolidamento degli apprendimenti

Five Songs of Northeastern Brazilian Folklore by Ernani Braga, Harmonized for Voice and Piano: A Performance Guide

This paper provides a performance analysis of one of Ernani Braga\u27s most well-regarded compositions, Cinco Cancoes Nordestinas do Folclore Brasileiro (Five Songs of Northeastern Brazilian Folklore). I include a biography of the composer, a complete catalogue of his songs, and an analysis of the music construction and technical performance challenges of his folk song cycle. By doing so, I also hope to draw attention to Braga\u27s compositional output for voice and piano, and to raise awareness of his importance as great Brazilian musician and accomplished composer

Geometrical constraints on dark energy models

This contribution intends to give a pedagogical introduction to the topic of dark energy (the mysterious agent supposed to drive the observed late time acceleration of the Universe) and to various observational tests which require only assumptions on the geometry of the Universe. Those tests are the supernovae luminosity, the CMB shift, the direct Hubble data, and the baryon acoustic oscillations test. An historical overview of Cosmology is followed by some generalities on FRW spacetimes (the best large-scale description of the Universe), and then the test themselves are discussed. A convenient section on statistical inference is included as well.Comment: 28 pages, 15 pages, lecture notes prepared for the ``Advanced Summer School in Physics 2007" organized by Cinvestav (Mexico DF