Principal component analysis of colour measurements of patinas and coating systems for outdoor bronze monuments

Principal Component Analysis (PCA) was applied on colour measurements performed on outdoor bronze patinas and protective coating systems on bronze coupons in order to monitor natural weathering and cleaning effects. PCA chemometric technique is shown to be a powerful tool to analyse the large measurement data set which is needed to characterise these kinds of system. The results are compared with previous work where the CIELAB L*a*b space was used, in order to spot the advantages and disadvantages of both techniques and how they can complete each other in order to set up a workflow when dealing with large datasets of colour measurements. As previously stated, quicker colour variations in the early stage of natural weathering of bronze coupons are characterised, which is mainly due to lightness reduction. PCA analysis helps to visualise the different behaviour upon cleaning procedure of different monument patinas and colour difference reduction due to cleaning. It gives the advantage in a first screening phase to possibly highlight the presence of outliers, check the level of noise in the spectra, and select the variables which carry more information. Its integration in a workflow for colour measurement can help in speeding up the process of later analysing data with the well-established CIELAB system.     

Sparks in the dark: the attraction of electricity in the eighteenth century

Electricity was the craze of the eighteenth century. Thrilling experiments became forms of polite entertainment for ladies and gentlemen who enjoyed feeling sparks, shocks and attractions on their bodies. Popular lecturers designed demonstrations that were performed in darkened salons to increase the spectacle of the so-called electric fire. Not only did the action, the machinery and the ambience of such displays match the culture of the libertine century, it also provided new material for erotic literature.     

Familiarity and relatedness: Effects on social learning about foods by Norway rats and Mongolian gerbils

In recent experiments in which the social influences on feeding in Mongolian gerbils were investigated, observer gerbils acquired food preferences from conspecific demonstrators only if the demonstrators and observers were either related or familiar. Even then, the effects of demonstrator gerbils on observers’ food choices lasted less than 24 h. In similar experiments with Norway rats, the familiarity/relatedness of demonstrators and observers had little effect on social learning, and the demonstrators’ influence on observers’ food choices lasted many days. We examined the causes of these differences and found that, after observer gerbils interacted with either unfamiliar or familiar conspecific demonstrators that had been fed using procedures typically used to feed demonstrator rats, they showed long-lasting social learning about foods, whereas observer rats interacting with conspecific demonstrators that had been fed as demonstrator gerbils normally are fed showed effects of familiarity/relatedness to demonstrators on their social learning about foods. Procedural differences, rather than species differences, seem to be responsible for reported inconsistencies in social learning about foods by rats and gerbils.     

Adapting Reform Ideas in Different Mathematics Classrooms: Beliefs Beyond Mathematics

The goals of this study are to understandelementary school teachers' beliefs andpractices and to unveil factors that influencethe way teachers adapt mathematics reformrhetoric when trying to adopt it. In theresearch, I searched for beliefs beyondmathematics that influence teachers' decisionsand choices for teaching mathematics. Workingwith children from different socioeconomicbackgrounds, teachers interpret reform indifferent ways. Based on their concept of students' needs, teachers select which partsof the reform documents are appropriate fortheir students. While children from uppersocioeconomic backgrounds experience problemsolving, those from lower socioeconomicbackgrounds undergo rote learning. Because notall children have the opportunity to learn thesame quality mathematics, the emerging concernof this study is the issue of equity inmathematics teaching.     

Design of Learner-centered Tools for Continuous Training in SMEs

Multimedia and networked educational tools may provide an effective answer to the training needs of small-medium enterprises (SMEs). In accordance with this idea, we are developing a project called Qualification 2000 supported by the E.C.'s Adapt initiative. The project focuses on the use of educational technology for continuous training in informatics and its applications in office automation. The target is women employed in small-medium enterprises. The attitude of the target towards innovation makes the design of effective tools a particularly delicate problem; thus, careful design of the interface is particularly important to make these kinds of tools productive. With these ideas in mind, we carried out a series of interviews with employees, aimed at deriving a core of common needs and difficulties. The results of the interviews have been used to build a learner-centred interface based on experimental pedagogical assumptions. © IFIP, published by K luwer Academic Publishers     

Teachers’ guidance,family participation and track choice: the educational disadvantage of immigrant students in Italy

In Italy, as in other European countries, students of foreign origin are over-represented in the vocational school tracks, with relevant consequences on their limited chances of attaining a university degree. While research has long underlined the weight that a family’s social, cultural and economic capital has on a child’s school performance, educational expectations and choices, the role that school and teachers themselves play in the transition from lower to upper secondary school has been rarely explored in Italian sociological research. The present study aims to bridge this gap in the literature, showing how teachers’ orienting practices, interacting with highly differentiated patterns of family participation in the school guidance process, can play a relevant role in reproducing foreign-origin students’ segregation into the lower tracks of the school system.     

Social marking of cognitive operations. The effect of different social rules

The present study is concerned with assessing whether social marking (i.e. the correspondence between the correct solution of a task and some known social rule) is a mechanism of cognitive progress which depends on specific forms of rule represented in the task material. Results of an experiment on a spatial transformation task (N=sixty-four non-conserving 5–6-year-olds) showed no significantly different levels of cognitive progress for subjects who transformed the spatial arrangement of a classroom or of a theatre. Significant difference emerged only when a deviation from the normally regulated arrangement were represented. In the condition where the deviation concerned the theatre subjects showed the lower level of progress. It was concluded that the beneficial effect of social marking may depend on the form of rule represented. Results were discussed with respect to children’s knowledge of the relative alterability of different types of rules.     

Brain Processes in Mothers and Nulliparous Women in Response to Cry in Different Situational Contexts: A Default Mode Network Study

SYNOPSIS

Objective: In everyday life, parents must respond to and interact with children while in different situational contexts. How situational contexts influence parents’ responses has not been systematically studied. Here we investigated mothers’ versus nonmothers’ neural responses to infant vocalizations in different situations with different task demands. Design: Using fMRI in 21 women (10 mothers), we explored the effects of being distracted by self-oriented (self-referential decisions about personality adjectives) versus goal-oriented (syllabic counting of personality adjectives) tasks while listening to infant cry in comparison with other emotional sounds (infant laughing, adult crying) on the activity of two medial nodes of the Default Mode Network (DMN): the medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC). Results: In the self-oriented task while listening to infant cry, both mothers and nulliparas showed (weak) activation of the DMN; this response likely reflects a shift of attention from the task to the cry. In the goal-oriented task, mothers, not nulliparas, showed (weak) activation of the DMN; this result is compatible with interference of emotional sounds while attending to a goal-oriented task, an activity that deactivates the DMN. Conclusions: Mothers are prone to process infant cry and emotional sounds and are less distracted from doing so by situational contexts, demonstrating their greater sensitivity to emotional sounds such as cry. By contrast, situational context influenced brain responses to infant sounds in nulliparas.     

Self-Cognition and Parental Brain

SYNOPSIS

A key feature of parenting is that it is observable starting from behaviors that are performed daily by adult caregivers during repeated interactions with the child. Functional magnetic resonance imaging (fMRI) research on parental brain should integrate settings that resemble ecologies of situations in which parents typically care for children. However, as our commentators point out, ecological settings in fMRI research are challenging and require a multiperspective approach that systematically considers psychological and behavioral complexities of “mommy brain” to better understand how contingent mental states of mothers articulate with specific multi-tasking situations.