"Evil cats" and "jelly floods": young children’s collective constructions of digital art-making in the early years classroom

Digital technologies have the potential to offer new opportunities for children’s expressive arts practices. While adult expectations surround and shape children’s visual art-making on paper in the early years classroom, such expectations are not so established in relation to digital art-making. So how do children make sense of digital art-making when it is newly introduced into the classroom and adult input is minimal? Drawing on a social semiotic ethnographic perspective, this paper explores this question by examining instances of 4-5 year olds’ spoken dialogue around the computer during a week in which digital art-making was first introduced into the classroom. Analysis focused on interactions where children proposed, reinforced or challenged conceptions of digital art-making. These interactions demonstrated that children’s digital art-making was negotiated and constructed through particular processes. Three such processes are presented here: the use of collective motifs and metaphors; attributing ‘expert’ status; and polarizing conflicts. Understanding these processes offers a starting point for thinking about how a new activity like digital art-making can be integrated into the early years classroom and supported by practitioners

Narrative in young children’s digital art-making

Digital technologies have material and social properties that have the potential to create new opportunities for children’s expressive arts practices. The presence and development of oral narratives in young children’s visual art-making on paper has been noted in previous research, but little is known about the narratives children create when they engage in digital art-making. How do young children construct narratives during digital art-making? How do the features of these narratives relate to the social and material properties of the digital resources they are using? How can looking at these narratives inform and enrich our understanding of children’s art-making in general? Drawing on a social semiotic perspective, these questions are explored through an in-depth analysis of narrative in three examples of 4-5 year olds’ digital art-making. On the basis of the analysis, features of oral narrative in young children’s digital art-making are suggested and these are linked to potentially influential properties of the digital resources. Being aware of these features and properties offers a starting point for thinking about what digital resources can offer in the context of young children’s art-making. The findings also prompt us to be aware of the diverse potentials that exist in children’s art-making practices regardless of the resources being used

Imitative or Iconoclastic? How young children use ready-made images in digital art

Digital art-making tends to foreground the inclusion of ready-made images in children’s art. While some lament children’s use of such images, suggesting that they constrain creativity and expression (McLennan, 2007; Szyba, 1999), others have argued that ready-made digital materials offer children the opportunity to create innovative and potentially iconoclastic artefacts through processes of ‘remix’ (Lankshear & Knobel, 2006) and ‘mash-up’ (Lamb, 2007). In order to further this debate, observations are needed to explore the different ways that children use ready-made images in their digital art and the various purposes that these images can serve. Adopting a social semiotic perspective, this paper offers an in-depth examination of five episodes of 4-5 year olds’ digital art-making that collectively demonstrate the diversity of approaches that young children take towards the inclusion of ready-made images in their digital art-making. The paper discusses these findings in relation to suggestions for what adults can do to support children to adopt a playful and critically aware approach to the use of ready-made images in digital art-making

Physical interpretation of the near-infrared colours of low-redshift galaxies

We use empirical techniques to interpret the near-infrared (near-IR) colours of a sample of 5800 galaxies drawn from Sloan Digital Sky Survey (SDSS) main spectroscopic sample with YJHK photometry from the United Kingdom Infrared Deep Sky Survey (UKIDSS) data release 1. Our study focuses on the inner 3 arcsec regions of the galaxies sampled by the SDSS fibre spectra. We study correlations between near-IR colours measured within this aperture and physical parameters derived from the spectra. These parameters include specific star formation rate (SFR), stellar age, metallicity and dust attenuation. All correlations are analysed for samples of galaxies that are closely matched in redshift, in stellar mass and in concentration index. Whereas more strongly star-forming galaxies have bluer optical colours, the opposite is true at near-IR wavelengths ¿ galaxies with higher specific SFR have redder near-IR colours. This result agrees qualitatively with the predictions of models in which thermally pulsing asymptotic giant branch (TP-AGB) stars dominate the H- and K-band light of a galaxy following a burst of star formation. We also find a surprisingly strong correlation between the near-IR colours of star-forming galaxies and their dust attenuation as measured from the Balmer decrement. Unlike optical colours, however, near-IR colours exhibit very little dependence on galaxy inclination. This suggests that the correlation of near-IR colours with dust attenuation arises because TP-AGB stars are the main source of dust in the galaxy. Finally, we compare the near-IR colours of the galaxies in our sample to the predictions of three different stellar population models: the Bruzual & Charlot model, a preliminary version of a new model under development which includes a new prescription for AGB star evolution, and the Maraston model

The longitudinal thickness of air-shower fronts

Linsely (1983) has proposed a technique for the detection and analysis of air showers at large distances from the shower axis based on a measurement of the shower front thickness and the assumption that this thickness is closely related to the core distance. Some of the problems involved with realizing such a technique were investigated, and some related observations are reported. The practical problems of how consistent the measurements of the shower front would be, how one would use the measurement, and how the rate of triggered events would depend on the minimum pulse width required are studied

Intervening Metal Systems in GRB and QSO sight-lines: The Mgii and Civ Question

Prochter et al. 2006 recently found that the number density of strong intervening 0.5<z<2 MgII absorbers detected in gamma-ray burst (GRB) afterglow spectra is nearly 4 times larger than in QSO spectra. We have conducted a similar study using CIV absorbers. Our CIV sample, consisting of a total of 20 systems, is drawn from 3 high resolution and high to moderate S/N VLT/UVES spectra of 3 long-duration GRB afterglows, covering the redshift interval 1.6< z<3.1. The column density distribution and number density of this sample do not show any statistical difference with the same quantities measured in QSO spectra. We discuss several possibilities for the discrepancy between CIV and MgII absorbers and conclude that a higher dust extinction in the MgII QSO samples studied up to now would give the most straightforward solution. However, this effect is only important for the strong MgII absorbers. Regardless of the reasons for this discrepancy, this result confirms once more that GRBs can be used to detect a side of the universe that was unknown before, not necessarily connected with GRBs themselves, providing an alternative and fundamental investigative tool of the cosmic evolution of the universe.Comment: 21 pages, 4 figures, ApJ accepted, Revised after Referee Repor

An Investigation of the Cycle Extraction Properties of Several Bandpass Filters Used to Identify Business Cycles

The purpose of this article is to investigate the ability of bandpass filters commonly used in economics to extract a known periodicity. The specific bandpass filters investigated include a Discrete Fourier Transform (DFT) filter, together with those proposed by Hodrick and Prescott (1997) and Baxter and King (1999). Our focus on the cycle extraction properties of these filters reflects the lack of attention that has been given to this issue in the literature, when compared, for example, to studies of the trend removal properties of some of these filters. The artificial data series we use are designed so that one periodicity deliberately falls within the passband while another falls outside. The objective of a filter is to admit the ‘bandpass’ periodicity while excluding the periodicity that falls outside the passband range. We find that the DFT filter has the best extraction properties. The filtered data series produced by both the Hodrick-Prescott and Baxter-King filters are found to admit low frequency components that should have been excluded

A micro-photonic stationary optical delay line for fibre optic time domain OCT

We present results for the characterisation of a micro-photonic stationary optical delay line. The delay line is intended to generate true time delays for a fibre optic based optical coherence tomography system