Development of new imaging techniques for the study and interpretation of late Rembrandt paintings

Recent macro-XRF scanning of Rembrandt’s Selfportrait from 1669 in the Mauritshuis – as part of the ReVisRembrandt project – has revealed significant new information about the pigments and build-up of the painting. The elemental distribution maps make clear that the umber-rich ground plays a very important role in the final appearance of this painting, information that is highly relevant for the study of this self-portrait, as well as many other late Rembrandt paintings. It was also possible to image the presence of organic lakes (by means of the potassium map) and bone black (by means of the calcium and phosphorus maps) in the upper paint layers. In addition to conventional investigative techniques, such as x-radiography and infrared imaging, it is anticipated macro-XRF scanning will become an important diagnostic tool for conservators and art historians alike

Investigation of a 15th century silverpoint drawing via µ-XRF

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Adolescents' Commitment to Developing Talent: The Role of Peers in Continuing Motivation for Sports and the Arts

The role of peer relationships in supporting or hindering adolescents' talent development has received little research attention, despite the importance of peers in adolescents' lives. We conducted semi-structured in-depth interviews with 41 adolescents talented in sports or the arts, and their parents, to investigate (a) the role of peer relationships in adolescents' continued involvement in their talent activities, (b) possible differences in this role by activity domain, and (c) possible gender differences. Thematic analysis indicated that peers typically played a positive function in supporting the continued involvement of talented adolescents in their talent activities. There were differences in opportunities for peer relationships and social satisfaction between in-school and out-of school activities, but not between activity domains. Both males and females mentioned equally social benefits of such involvement. However, females mentioned receiving negative peer attention more frequently than males, and more often cited social dissatisfaction as a significant contributor to decreased involvement or quitting.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45286/1/10964_2004_Article_411240.pd

Splines and Wavelets on Geophysically Relevant Manifolds

Analysis on the unit sphere $\mathbb{S}^{2}$ found many applications in seismology, weather prediction, astrophysics, signal analysis, crystallography, computer vision, computerized tomography, neuroscience, and statistics. In the last two decades, the importance of these and other applications triggered the development of various tools such as splines and wavelet bases suitable for the unit spheres $\mathbb{S}^{2}$, $\>\>\mathbb{S}^{3}$ and the rotation group $SO(3)$. Present paper is a summary of some of results of the author and his collaborators on generalized (average) variational splines and localized frames (wavelets) on compact Riemannian manifolds. The results are illustrated by applications to Radon-type transforms on $\mathbb{S}^{d}$ and $SO(3)$.Comment: The final publication is available at http://www.springerlink.co

Non-destructive characterisation and classification of ceramic artefacts using pEDXRF and statistical pattern recognition

Background: Portable energy dispersive X-ray fluorescence (pEDXRF) spectrometry analysis was applied for the characterisation of archaeological ceramic findings from three Neolithic sites in Serbia. Two dimension reduction techniques, principal component analysis (PCA) and scattering matrices-based dimension reduction were used to examine the possible classification of those findings, and to extract the most discriminant features. Results: A decision-making procedure is proposed, whose goal is to classify unknown ceramic findings based on their elemental compositions derived by pEDXRF spectrometry. As a major part of decision-making procedure, the possibilities of two dimension reduction methods were tested. Scattering matrices-based dimension reduction was found to be the more efficient method for the purpose. Linear classifiers designed based on the desired output allowed for 7 of 8 unknown samples from the test set to be correctly classified. Conclusions: Based on the results, the conclusion is that despite the constraints typical of the applied analytical technique, the elemental composition can be considered as viable information in provenience studies. With a fully-developed procedure, ceramic artefacts can be classified based on their elemental composition and well-known provenance

Sex Differences in Self-Concept and Symptoms of Depression During the Transition to College

In an investigation of sex differences in adaptation to college, real and ideal self-concept and symptoms of depression were studied longitudinally in a sample of 287 students. Survey data were collected at a summer orientation and one semester into freshman year. No sex differences in self-concept were found before college, but males' real self-concept became more positive over the transition. Females were more depressed than males at both times, although depressive symptom scores increased in both sexes. Real self-concept scores were negatively correlated with depressive symptoms in both sexes at both times, while the discrepancy between real and ideal self-concepts was positively correlated with depressive symptoms among females before college and in both sexes midway through freshman year. A one-year follow-up revealed that females' real self-concept scores increased to match those of males by mid-sophomore year. These sex differences are discussed in relation to psychological development during adolescence.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45284/1/10964_2004_Article_411446.pd