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This study was initiated in an area of school science, earth science education, which has been little explored. A sample of 493 Portuguese pupils aged 10-11 and 14-15 (at the beginning and end of secondary schooling) was involved. The study used interviews and a written questionnaire to probe the ideas about the origin and development of earth and life which were held by pupils who had not been taught those topics, the conjecture being that pupils would have developed their own beliefs. A significant number of commonly-held ideas were found which were independent of those relating to the scientific consensus. Using suggestions provided by existing teaching-learning models, guidelines are developed which should help learners to challenge their homespun views and promote their own conceptual changes.

The growing human population, together with the inefficient use of natural resources, has been dramatically increasing the production of food waste, which poses serious economic, environmental, and social problems. Being so, it is necessary to increase the efficiency of food consumption so as to reduce its waste and to convert the remaining residues into societal benefits. Since this biowaste is rich in polyphenols and vitamins, it could become the feedstock for the production of important value-added compounds for the pharmaceutical (e.g., food supplements) and cosmetic (e.g., creams and shampoos) industries. In this work, partition studies of one polyphenol (epicatechin) and two B-complex vitamins (cyanocobalamin and nicotinic acid) were performed in biodegradable Aqueous Two-Phase Systems (ATPS) based on ethyl lactate and on organic salts (disodium tartrate, tripotassium citrate, and trisodium citrate) at 298.15 K and 0.1 MPa. The largest partition coefficient (K) and extraction efficiency (E) were obtained for vitamin B12 (K=78.56, E=97.5%) for the longest tie line TLL=77.66% in the ATPS {ethyl lactate (1) + tripotassium citrate (2) + water (3)}. All the extractions were obtained with low biomolecule mass losses in quantification (<5%) and after a thorough study of pH influence in the UV–Vis absorbance spectra.

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In this paper, we report on a small-scale study designed to estimate science teachers' awareness of ndings derived from research in science education and other branches of educational research. The study was conducted among experienced science teachers in Portugal who were following advanced professional training programmes, usually leading to Masters' degrees in science education. The results indicate that science teachers' knowledge of education research ndings is generally very limited. What teachers regard as sound pedagogical knowledge is usually derived from personal experience and 'common sense' and does tend not to be questioned by them as to its compatibility with the results of research. The outcome of the study provides evidence of the existence of a serious gap between research and the practice of science education. In the light of these ndings, the authors propose that to narrow this gap should be a major task to be addressed by researchers and practitioners.