Striving against invalidity in qualitative research: Discussing a reflective framework

The aim of this paper is to discuss a reflective validation framework related with the study of teaching approaches, teaching styles or teaching orientations of university academics. In the recent years, and particularly since the eighties, there have been a growing number of investigations linking teaching conceptions with teaching practices. The majority of investigations dealing with university teachers’ conceptions and practices draw their conclusions based on indirect observation, since data gathering involves mainly semi-structured interviews or the application of questionnaires and inventories. Therefore ‘only-half-the-story’ has been reported. The presented validation framework has a five-part three-stage structure and was built upon earlier work (Selvaruby, O’Sullivan, & Watts, 2007). In this model validity is conceptualized as an ‘iterative-interactive-process’, therefore integrating a set of specific strategies envisaging the maximization of scientific quality. The application of the model is illustrated by using it for the discussion of a longitudinal study involving the investigation of the relationship between questioning practices and Trigwell and co-workers’ concept of preferential teaching approaches (Trigwell, Prosser & Taylor, 1994). Field work of this naturalistic-interpretative research was conducted during two academic years (2009/2010 and 2010/2011) and implied close collaboration with a group of four university teachers lecturing biology to undergraduates.This work was financed by Fundação para a Ciência e a Tecnologia (SFRH/BD/44611/2008) and by Fundos FEDER através do Programa Operacional Fatores de Competitividade – COMPETE e por Fundos Nacionais através da FCT (PTDC/CPE-CED/117516/2010)

How does geographic distance affect credit market access in Niger ?

Distances involved in accessing basic services can constitute a major barrier to development. This paper analyzes the relationship between the distance separating households from microfinance institutions'offices in Niger, and the low levels of development and performance of the microfinance sector in the country. To cope with the effects of geographical distance, microfinance institutions adapt their policies through more restrictive loan conditions, higher interest rates, and more intensive screening. The authors to discuss the tension between access and sustainability in the context of financial services for the poor.

Preparation of zinc-oxide and zinc-sulfide powders by controlled precipitation from aqueous-solution

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Morphology of galaxies with quiescent recent assembly history in a Lambda-CDM universe

The standard disc formation scenario postulates that disc forms as the gas cools and flows into the centre of the dark matter halo, conserving the specific angular momentum. Major mergers have been shown to be able to destroy or highly perturb the disc components. More recently, the alignment of the material that is accreted to form the galaxy has been pointed out as a key ingredient to determine galaxy morphology. However, in a hierarchical scenario galaxy formation is a complex process that combines these processes and others in a non-linear way so that the origin of galaxy morphology remains to be fully understood. We aim at exploring the differences in the formation histories of galaxies with a variety of morphology, but quite recent merger histories, to identify which mechanisms are playing a major role. We analyse when minor mergers can be considered relevant to determine galaxy morphology. We also study the specific angular momentum content of the disc and central spheroidal components separately. We used cosmological hydrodynamical simulations that include an effective, physically motivated supernova feedback that is able to regulate the star formation in haloes of different masses. We analysed the morphology and formation history of a sample of 15 galaxies of a cosmological simulation. We performed a spheroid-disc decomposition of the selected galaxies and their progenitor systems. The angular momentum orientation of the merging systems as well as their relative masses were estimated to analyse the role played by orientation and by minor mergers in the determination of the morphology. We found the discs to be formed by conserving the specific angular momentum in accordance with the classical disc formation model. The specific angular momentum of the stellar central spheroid correlates with the dark matter halo angular momentum and determines a power law. AbridgedComment: 10 pages, 9 figures, A&A in pres

Transient features of quantum open maps

We study families of open chaotic maps that classically share the same asymptotic properties -- forward and backwards trapped sets, repeller dimensions, escape rate -- but differ in their short time behavior. When these maps are quantized we find that the fine details of the distribution of resonances and the corresponding eigenfunctions are sensitive to the initial shape and size of the openings. We study phase space localization of the resonances with respect to the repeller and find strong delocalization effects when the area of the openings is smaller than $\hbar$.Comment: 7 pages, 7 figure