The University as a site for transformation around sustainability

YesUniversities are increasingly being seen as key sites for transformation around sustainability. However, much of the literature in this area uses the terms transformation and transformative learning rather uncritically. Moreover, there is little extant research which has investigated the links between transformative learning theories and Education for Sustainability (EfS). This paper reports on a research project which explored academic and student perceptions of the opportunities for transformation around sustainability in two UK universities. The findings suggest that, despite shared understanding about the nature of pedagogic approaches that promote deep learning, academics are wary about promoting transformation beyond the professional sphere and students are more likely to have transformative experiences outside the formal curriculum. There are indications that although universities have significant potential as sites for transformation around sustainability, at present, this is not being achieved

Microphase separation in Pr0.67Ca0.33MnO3 by small angle neutron scattering

We have evidenced by small angle neutron scattering at low temperature the coexistence of ferromagnetism (F) and antiferromagnetism (AF) in Pr0.67Ca0.33MnO3. The results are compared to those obtained in Pr0.80Ca0.20MnO3 and Pr0.63Ca0.37MnO3, which are F and AF respectively. Quantitative analysis shows that the small angle scattering is not due to a mesoscopic mixing but to a nanoscopic electronic and magnetic ''red cabbage'' structure, in which the ferromagnetic phase exists in form of thin layers in the AF matrix (stripes or 2D ''sheets'').Comment: 4 figure

The rotation of alpha Oph investigated using polarimetry

Recently we have demonstrated that high-precision polarization observations can detect the polarization resulting from the rotational distortion of a rapidly rotating B-type star. Here we investigate the extension of this approach to an A-type star. Linear-polarization observations of $\alpha$ Oph (A5IV) have been obtained over wavelengths from 400 to 750 nm. They show the wavelength dependence expected for a rapidly-rotating star combined with a contribution from interstellar polarization. We model the observations by fitting rotating-star polarization models and adding additional constraints including a measured $v_e \sin{i}$. However, we cannot fully separate the effects of rotation rate and inclination, leaving a range of possible solutions. We determine a rotation rate $\omega = \Omega/\Omega_ c$ between 0.83 and 0.98 and an axial inclination i > 60 deg. The rotation-axis position angle is found to be 142 $\pm$ 4 deg, differing by 16 deg from a value obtained by interferometry. This might be due to precession of the rotation axis due to interaction with the binary companion. Other parameters resulting from the analysis include a polar temperature Tp = 8725 $\pm$ 175 K, polar gravity $\log{g_p} = 3.93 \pm 0.08$ (dex cgs), and polar radius $R_{\rm p} = 2.52 \pm 0.06$ Rsun. Comparison with rotating-star evolutionary models indicates that $\alpha$ Oph is in the later half of its main-sequence evolution and must have had an initial $\omega$ of 0.8 or greater. The interstellar polarization has a maximum value at a wavelength ($\lambda_{\rm max}$) of $440 \pm 110$ nm, consistent with values found for other nearby stars.Comment: 14 pages, 11 figures, 5 tables, Accepted in MNRA

Light and Motion in SDSS Stripe 82: The Catalogues

We present a new public archive of light-motion curves in Sloan Digital Sky Survey (SDSS) Stripe 82, covering 99 deg in right ascension from RA = 20.7 h to 3.3 h and spanning 2.52 deg in declination from Dec = -1.26 to 1.26 deg, for a total sky area of ~249 sq deg. Stripe 82 has been repeatedly monitored in the u, g, r, i and z bands over a seven-year baseline. Objects are cross-matched between runs, taking into account the effects of any proper motion. The resulting catalogue contains almost 4 million light-motion curves of stellar objects and galaxies. The photometry are recalibrated to correct for varying photometric zeropoints, achieving ~20 mmag and ~30 mmag root-mean-square (RMS) accuracy down to 18 mag in the g, r, i and z bands for point sources and extended sources, respectively. The astrometry are recalibrated to correct for inherent systematic errors in the SDSS astrometric solutions, achieving ~32 mas and ~35 mas RMS accuracy down to 18 mag for point sources and extended sources, respectively. For each light-motion curve, 229 photometric and astrometric quantities are derived and stored in a higher-level catalogue. On the photometric side, these include mean exponential and PSF magnitudes along with uncertainties, RMS scatter, chi^2 per degree of freedom, various magnitude distribution percentiles, object type (stellar or galaxy), and eclipse, Stetson and Vidrih variability indices. On the astrometric side, these quantities include mean positions, proper motions as well as their uncertainties and chi^2 per degree of freedom. The here presented light-motion curve catalogue is complete down to r~21.5 and is at present the deepest large-area photometric and astrometric variability catalogue available.Comment: MNRAS accepte

A study of the F-giant star θ Scorpii A: a post-merger rapid rotator?

We report high-precision observations of the linear polarization of the F1III star θ Scorpii. The polarization has a wavelength dependence of the form expected for a rapid rotator, but with an amplitude several times larger than seen in otherwise similar main-sequence stars. This confirms the expectation that lower-gravity stars should have stronger rotational-polarization signatures as a consequence of the density dependence of the ratio of scattering to absorption opacities. By modelling the polarization, together with additional observational constraints (incorporating a revised analysis of Hipparcos astrometry, which clarifies the system's binary status), we determine a set of precise stellar parameters, including a rotation rate ω (= Ω/Ωc ≥ 0.94, polar gravity log (gp)= 2.091 +0.042-0.039 (dex cgs), mass 3.10 +0.37-0.32 M⊙, and luminosity log (L/L⊙) =3.149+0.041-0.028. These values are incompatible with evolutionary models of single rotating stars, with the star rotating too rapidly for its evolutionary stage, and being undermassive for its luminosity. We conclude that θ Sco A is most probably the product of a binary merger