Ethyl Silicate for Unbaked Earth Tablets Conservation: Evaluation of the Physico-mechanical Aspects

ABSTRACT

Preservation of cuneiform tablets made with clay minerals is an ongoing conservation issue. A treatment based on TEOS consolidation has been used since 1996 at the Louvre museum. The characterization of the tablets pointed out kaolinite, illite, and smectite as the three main clay minerals constituting the objects. In this research, the physico-mechanical aspects of the treatment are investigated. The penetration depth of the TEOS solution and the gradient induced are quantified using laboratory samples. TEOS treatment preserves the macroscopic swelling and the vapour transfer properties, but modifies the clay’s affinity to moisture. Elastic properties are gradually improved for all clays, but only kaolinite’s strength increases significantly. The impact of TEOS treatment on the natural behaviour related to the respective structure of the clays is considered, and the amount of kaolinite required to create adequate reactions appears to be of interest for conservation treatments.     

A Developmental Study of the Self-Prioritization Effect in Children Between 6 and 10 Years of Age

Self-biases are well described in adults but remain poorly understood in children. Here, we investigated in 6–10 year-old children (N = 132) the self-prioritization effect (SPE), a self-bias which reflects, in adults, the perceptual advantage for stimuli arbitrarily associated with the self as compared to those associated with other persons. We designed a child-friendly adaptation of a paradigm originally introduced in adults by Sui, He, and Humphreys (2012) in order to test whether the SPE also occurs in children and if so, to determine its evolution with age. A robust SPE was obtained from the age of 6, and this effect was similar-sized in our four age groups. These findings are discussed with reference to the development of the self during childhood.     

Le Logiciel ‘Derive’ comme revelateur de phenomenes didactiques lies a l'utilisation d'environnements informatiques pour l'apprentissage

In this article, we address the issue of integration of computer environments in the mathematics secondary curriculum, by referring to the results of a research project carried out with the software DERIVE. Firstly, we present the research project and its theoretical framework, secondly, we evidence some didactical phenomenas linked to the DERIVE transposition of mathematical knowledge and learning processes in this environment which, in our opinion, play a crucial role in integration issues.This revised version was published online in September 2005 with corrections to the Cover Date.     

The breadth of peer relationships among preschoolers: an application of the Q-connectivity method to externalizing behavior

Preschoolers' (M(age) = 48.7 months) social breadth (the number of peer children interact with and the frequency of these interactions) and the relations between breadth and externalizing behaviors were examined using the Q-connectivity method. After considering age, sex, and classroom effects on social breadth, children's externalizing behaviors were studied in relation to levels of social breadth across variations in frequency of exposure to peers and to patterns of decline in social breadth. Externalizing preschoolers occasionally interacted with most of their classmates. However, their individual peer networks moderately to rapidly became selective, and they engaged in repeated interactions with a relatively small number of peers. Although there were no sex effects, significant age and classroom effects were obtained.     

Correction to: Learning About Archaeology and Prehistoric Life

Science & Education - The original article unfortunately contains incorrect figures 6 to 13.     

A Contribution of the Computer to Biology Education at the University

Summaries

English

At the O.P.E. Laboratory, computer‐based biology dialogues result in a new pedagogical situation which could not be achieved by any other method.

This paper describes part of O.P.E. embryology dialogues, designed for undergraduate medical and biology students, and concerning interactions between inductive and competent tissues during embryonic development. Each student using these dialogues is in a position to proceed, in an active manner, through three principal stages in the knowledge of the competence concept: determination of experimental criteria of a state of competence; analysis of evolution of competence in course of time; detection of modifications of competence of a tissue towards sequential inductors.

In the course of the dialogue, each student has to interpret various experimental results, verify hypotheses and conduct in his own way a series of simulated experiments (students have no other chance of carrying out this kind of embryology experiment). The validity of the student's reasoning and his experimental methodology are constantly controlled.

These computer‐based biology dialogues are not intended to supersede other pedagogical activities. They are designed to be a new and specific contribution to comprehension, mastery, and even modelling, of biological concepts and mechanisms, and appear to meet actual requirements of biology education.