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Noemi Orazi Fulvio Mercuri Ugo Zammit Stefano Paoloni Massimo Marinelli Augusto Giuffredi 《文物保护研究》2016,61(4):236-244
In this work we investigate various aspects of the finishing process in ancient bronze sculptures by means of active infrared thermography (IRT). Active IRT provides information on surface and sub-surface features of the investigated artefact, by analysing the heat diffusion process induced within the sample by appropriate thermal stimulations usually produced by absorption of light emitted by different sources. The aim of this research is, in particular, to investigate the processing of bronze surfaces, revealing repairs like plugs, fillings, local castings and concealed marks. 相似文献
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This paper contributes to the literature on the observed research funding and scientific productivity gender gap in science. On the basis of very detailed information for a sample of 276 academics at the University of Turin over a ten year period, we develop a robust new model that takes into account the three main stages of the funding-productivity nexus: applying for a grant, successful fund raising and conducting the research, to investigate at which stage the gender gap emerges. In the model, we control for differences – not previously examined together - in the time allocated to teaching, administration and child care, which might moderate the gender effect. Using a Two-Stage Least Square (2SLS) model we control, for selection into funding, endogeneity of career progress and endogeneity of funding success, and find, first, that researchers who apply for grants are active in teaching and administration and show persistent funding application behaviour, but find no evidence of a significant gender bias; second, when we control for application selection, the negative gender correlation with funding acquisition becomes stronger, while teaching is negatively correlated to the amount of funding raised; and, third, controlling for selection and reverse causality, we find that funding is not associated to higher research productivity. At all stages of the funding-productivity nexus we find negative, albeit insignificant, secondary gender effects associated with administrative tasks, but less so with teaching. In the research impact-quality estimations we provide evidence of a ‘motherhood penalty’ for female academics with young children who did not apply for funding (including evidence of a causal effect). In line with the literature, we find that, after controlling for children, female researchers are less productive in terms of publications, but not in terms of research quality or impact. 相似文献
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Energy is a central topic in physics and a key concept for understanding the physical, biological and technological worlds. It is a complex topic with multiple connections with different areas of science and with social, environmental and philosophical issues. In this paper we discuss some aspects of the teaching and learning of the energy concept, and report results of research on this issue. To immerse science teaching into the context of scientific culture and of the students’ cultural world, we propose to select specific driving issues that promote motivation for the construction of science concepts and models. We describe the design and evaluation of a teaching learning path developed around the issue of greenhouse effect and global warming. The experimentation with high school students has shown that the approach based on driving issues promotes students’ engagement toward a deeper understanding of the topic and favours further insight. The evolution of students’ answers indicates a progressively more correct and appropriate use of the concepts of heat, radiation, temperature, internal energy, a distinction between thermal equilibrium and stationary non equilibrium conditions, and a better understanding of greenhouse effect. Based on the results of the experimentation and in collaboration with the teachers involved, new materials for the students have been prepared and a new cycle of implementation, evaluation and refinement has been activated with a larger group of teachers and students. This type of systematic and long term collaboration with teachers can help to fill the gap between the science education research and the actual school practice. 相似文献
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Ugo Besson 《Science & Education》2013,22(5):1001-1042
This paper presents a history of research and theories on sliding friction between solids. This history is divided into four phases: from Leonardo da Vinci to Coulomb and the establishment of classical laws of friction; the theories of lubrication and the Tomlinson’s theory of friction (1850–1930); the theories of wear, the Bowden and Tabor’s synthesis and the birth of Tribology (1930–1980); nanotribology, friction at the atomic scale, and new fields of research (after 1980). Attention is given to recent research, so giving the sense of a topic that is still alive and currently an object of interest, with interpretative controversies. The development of explanatory and visual models is especially stressed, in connection with students’ common ideas and with didactic purposes. The history shows that many models proposed in the past have been modified but not abandoned, so that here the scientific evolution has worked more by adding than by eliminating. The last sections discuss problems and proposals on teaching friction and the possible uses in teaching of models, images and theories found in history. Concerning the role of the history in science teaching, the case of friction has particular features, because some recent developments are unknown to most teachers and many results, also not very recent, contrast with the laws usually proposed in textbooks. Here history can supply a number of models, examples and experiments which can constitute useful resources to improve student understanding, joining together objectives of cultural value and of better scientific knowledge. 相似文献
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Ugo Besson Lidia Borghi Anna De Ambrosis Paolo Mascheretti 《International Journal of Science Education》2013,35(10):1289-1313
We have developed a teaching‐learning sequence (TLS) on friction based on a preliminary study involving three dimensions: an analysis of didactic research on the topic, an overview of usual approaches, and a critical analysis of the subject, considered also in its historical development. We found that mostly the usual presentations do not take into account the complexity of friction as it emerges from scientific research, may reinforce some inaccurate students’ conceptions, and favour a limited vision of friction phenomena. The TLS we propose begins by considering a wide range of friction phenomena to favour an initial motivation and a broader view of the topic and then develops a path of interrelated observations, experiments, and theoretical aspects. It proposes the use of structural models, involving visual representations and stimulating intuition, aimed at helping students build mental models of friction mechanisms. To facilitate the reproducibility in school contexts, the sequence is designed as an open source structure, with a core of contents, conceptual correlations and methodological choices, and a cloud of elements that can be re‐designed by teachers. The sequence has been tested in teacher education and in upper secondary school, and has shown positive results in overcoming student difficulties and stimulating richer reasoning based on the structural models we suggested. The proposed path has modified the teachers’ view of the topic, producing a motivation to change their traditional presentations. The open structure of the sequence has facilitated its implementation by teachers in school in coherence with the rationale of the proposal. 相似文献
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Ugo Besson 《International Journal of Science Education》2013,35(14):1683-1714
This article describes a research study concerning students' conceptions and reasonings about fluids and pressure in static situations. After a preliminary survey involving interviews and observations in class, some written questions were answered by various groups, totalling 428 Italian and French pupils in upper secondary school, 458 first‐year university students in Belgium and 58 teachers‐in‐training. After briefly illustrating some results from previous research on this topic, the article introduces the guidelines and objectives of the current research, describes and discusses its results, highlighting some categories of the more diffuse conceptions and tendencies of reasoning, and supplies a few suggestions for teaching. It is shown, among other things, that the notion of hydrostatic pressure is strongly connected to the idea of weight and associated with all the ambiguities that usually go with the latter. Moreover, a critical point appears to be the difficulty in connecting local actions and global effects, the need for systemic reasonings that are capable of producing the mechanism with which to establish a situation of equilibrium. 相似文献
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Ugo Finardi 《Journal of Informetrics》2013,7(2):357-370
Since its introduction, the Journal Impact Factor has probably been the most extensively adopted bibliometric indicator. Notwithstanding its well-known strengths and limits, it is still widely misused as a tool for evaluation, well beyond the purposes it was intended for. In order to shed further light on its nature, the present work studies how the correlation between the Journal Impact Factor and the (time-weighed) article Mean Received Citations (intended as a measure of journal performance) has evolved through time. It focuses on a sample of hard sciences and social sciences journals from the 1999 to 2010 time period. Correlation coefficients (Pearson's Coefficients as well as Spearman's Coefficients and Kendall's τα) are calculated and then tested against several null hypotheses. The results show that in most cases Journal Impact Factors and their yearly variations do not display a strong correlation with citedness. Differences also exist among scientific areas. 相似文献
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Valentina Lo Cascio Giovanni Guzzo Francesco Pace Ugo Pace 《International Journal for Educational and Vocational Guidance》2013,13(2):135-149
In this study, we explored the unique and common contributions of anxiety, self-esteem, and family communication on indecisiveness among adolescents. Three hundred and fifty pupils from 13 to 16 years of age completed self-report measures on indecisiveness, quality of family communication, trait anxiety, and self-esteem. The findings in this study showed that students’ indecisiveness is predicted by family communication mediated by anxiety and self-esteem. These results have important implications for practice as it stresses the importance of anxiety and self-esteem. Nevertheless, the counselors could also focus on enhancing relationship-building skills by introducing the adolescents’ career formation as an adolescent–parent joint project. 相似文献
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