A test of arm-induced star formation in spiral galaxies from near-IR and Hα\alpha imaging

We have imaged a sample of 20 spiral galaxies in H$\alpha$ and in the near-infrared K band (2.2 um), in order to determine the location and strength of star formation in these objects with respect to perturbations in the old stellar population. We have found that star formation rates are significantly enhanced in the vicinity of K band arms. We have also found that this enhancement in star formation rate in arm regions correlates well with a quantity that measures the relative strengths of shocks in arms. Assuming that the K band light is dominated by emission from the old stellar population, this shows that density waves trigger star formation in the vicinity of spiral arms.Comment: 6 pages, 1 figure, accpeted for publication in MNRA

Sublattice asymmetry of impurity doping in graphene: A review

In this review we highlight recent theoretical and experimental work on sublattice asymmetric doping of impurities in graphene, with a focus on substitutional Nitrogen dopants. It is well known that one current limitation of graphene in regards to its use in electronics is that in its ordinary state it exhibits no band gap. By doping one of its two sublattices preferentially it is possible to not only open such a gap, which can furthermore be tuned through control of the dopant concentration, but in theory produce quasi-ballistic transport of electrons in the undoped sublattice, both important qualities for any graphene device to be used competetively in future technology. We outline current experimental techniques for synthesis of such graphene monolayers and detail theoretical efforts to explain the mechanisms responsible for the effect, before suggesting future research directions in this nascent field.Comment: 20 pages, 4 figures. Accepted for publication in Beilstein Journal of Nanotechnolog

Learning In the Visual Arts and the Worldviews of Young Children

This paper reports a research study into the effects of rich,sustained visual arts instruction on 103inner city 9-year-olds in two major US cities. We use the lenses of social learning theory, theories of motivation and self-efficacy, and recentresearch on artistic thinking to investigate the programs' effects on children's self-beliefs and creative thinking. The study enlisted a pre -- post measure,treatment-comparison group design along with structured observations of participant andcomparison group classrooms. The arts students made significant comparative gains on a selfefficacy scale and on an 'originality' subscale of a standard creativity test. These effects are attributed to children's engagement in art and to the social organization of instruction includingreinforcing peer and student -- adult relationships. Relationships between self-efficacy beliefs andtendencies to think originally are explored

ecp: An R Package for Nonparametric Multiple Change Point Analysis of Multivariate Data

There are many different ways in which change point analysis can be performed, from purely parametric methods to those that are distribution free. The ecp package is designed to perform multiple change point analysis while making as few assumptions as possible. While many other change point methods are applicable only for univariate data, this R package is suitable for both univariate and multivariate observations. Estimation can be based upon either a hierarchical divisive or agglomerative algorithm. Divisive estimation sequentially identifies change points via a bisection algorithm. The agglomerative algorithm estimates change point locations by determining an optimal segmentation. Both approaches are able to detect any type of distributional change within the data. This provides an advantage over many existing change point algorithms which are only able to detect changes within the marginal distributions