1,379 research outputs found

    Which space? Whose space? An experience in involving students and teachers in space design

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    To date, learning spaces in higher education have been designed with little engagement on the part of their most important users: students and teachers. In this paper, we present the results of research carried out in a UK university. The research aimed to understand how students and teachers conceptualise learning spaces when they are given the opportunity to do so in a workshop environment. Over a number of workshops, participants were encouraged to critique a space prototype and to re-design it according to their own views and vision of learning spaces to optimise pedagogical encounters. The findings suggest that the active involvement of students and teachers in space design endows participants with the power of reflection on the pedagogical process, which can be harnessed for the actual creation and innovation of learning spaces

    First in-situ sensing of volcanic gas plume composition at Boiling Lake (Dominica, West Indies)

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    Dominica, a small Caribbean island between Martinique (to the South) and Guadeloupe (to the North), is, because of the high number of potentially active volcanic centres,one of the most susceptible sites to volcanic risk in the Lesser Antilles arc. Seven major volcanic centres, active during the last 10ka, are considered likely to erupt again, and one of these is the Valley of Desolation volcanic complex. This is an area of 0.5 km2, located in on SW Dominica, where a number of small explosion craters, hot springs,bubbling pools and fumaroles testify for vigorous and persistent hydrothermal activity. Two main phreatic explosions have been documented in historical time (1880 and 1997), and the most likely centre of future activity is the Boiling Lake, a nearby high-T volcanic crater lake produced by an undated phreatic/phreatomagmatic explosion. Hot (80 to 90\ub0C) and acidic (4-6) waters normally characterize the steady-state activity of the lake, whereby which vigorous gas upwelling in the lake\u2019s centre feeds a persistent steaming plume. Stability of the Boiling Lake has occasionally been interrupted in the past (since 1876) by crises, the most recent in 2004, involving rapid draining of the lake and changes in water temperature and pH, likely as a result of drastic decrease of hydrothermal fluid input into the lake. While the chemical and isotopic composition of the lake waters is well characterised, there are no compositional data available for the gas plume leaving the lake, due to inherent difficulties in direct gas sampling. Here, we present the results of the first direct measurements of the Boiling Lake\u2019s plume, performed by using the MultiGAS technique in February 2012. We acquired 0.5 Hz time-series of H2O, CO2, H2S and SO2 plume concentrations,which were seen to peak (with maximum background-corrected concentrations of 3680, 101 and 25 ppm for respectively H2O, CO2 and H2S) during phases of visible increase in lake outgassing. SO2 was virtually absent in the plume. From the concentration data, the characteristic CO2/H2S (5.2\ub10.4) and H2O/CO2 (31.4\ub16) volatile ratios in the Boiling lake\u2019s atmospheric plume were derived. This reveals similar C to S signature for Boiling lake and Valley of Desolation (for which we also obtained data using the same technique), likely indicative of common source reservoir. The Boiling lake\u2019s plume is far more H2O-rich than the Valley of Desolation gas, suggesting that a significant fraction of in-plume H2O in the former originates from re-evaporation of the lake water itself. Our data here provide a first compositional baseline for quiescent volcanic gas emissions at Boiling Lake, and may form the basis to stimulate emerging geochemical monitoring programs in the area

    Chiral Rings of Deconstructive [SU(n_c)]^N Quivers

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    Dimensional deconstruction of 5D SQCD with general n_c, n_f and k_CS gives rise to 4D N=1 gauge theories with large quivers of SU(n_c) gauge factors. We construct the chiral rings of such [SU(n_c)]^N theories, off-shell and on-shell. Our results are broadly similar to the chiral rings of single U(n_c) theories with both adjoint and fundamental matter, but there are also some noteworthy differences such as nonlocal meson-like operators where the quark and antiquark fields belong to different nodes of the quiver. And because our gauge groups are SU(n_c) rather than U(n_c), our chiral rings also contain a whole zoo of baryonic and antibaryonic operators.Comment: 93 pages, LaTeX, PSTricks macros; 1 reference added in v

    Fractional differentiability for solutions of nonlinear elliptic equations

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    We study nonlinear elliptic equations in divergence form divA(x,Du)=divG.{\operatorname{div}}{\mathcal A}(x,Du)={\operatorname{div}}G. When A{\mathcal A} has linear growth in DuDu, and assuming that xA(x,ξ)x\mapsto{\mathcal A}(x,\xi) enjoys Bnα,qαB^\alpha_{\frac{n}\alpha, q} smoothness, local well-posedness is found in Bp,qαB^\alpha_{p,q} for certain values of p[2,nα)p\in[2,\frac{n}{\alpha}) and q[1,]q\in[1,\infty]. In the particular case A(x,ξ)=A(x)ξ{\mathcal A}(x,\xi)=A(x)\xi, G=0G=0 and ABnα,qαA\in B^\alpha_{\frac{n}\alpha,q}, 1q1\leq q\leq\infty, we obtain DuBp,qαDu\in B^\alpha_{p,q} for each p<nαp<\frac{n}\alpha. Our main tool in the proof is a more general result, that holds also if A{\mathcal A} has growth s1s-1 in DuDu, 2sn2\leq s\leq n, and asserts local well-posedness in LqL^q for each q>sq>s, provided that xA(x,ξ)x\mapsto{\mathcal A}(x,\xi) satisfies a locally uniform VMOVMO condition

    Comparison of cheeses from goats fed 7 forages based on a new health index.

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    This study proposed the General Health Index of Cheese (GHIC) as an indicator for the presence of health-promoting compounds in cheese and compared the antioxidant capacity and phenolic and fatty acid contents of cheeses from goats consuming 7 forage species. Ninety-one homogeneous Red Syrian goats were randomly assigned to 1 of 7 feeding treatments (Festuca arundinacea, Hordeum vulgare, Triticosecale, Pisum sativum, Trifolium alexandrinum, Vicia sativa, and Vicia faba minor). The housed goat groups received the scheduled forage ad libitum. Forage species affected the antioxidant capacity, the phenolic and fatty acid contents, the Health Promoting Index, and the GHIC. Trifolium alexandrinum, Triticosecale, and Hordeum vulgare showed a clear advantage in terms of beneficial fatty acids content in goat cheese. Cheese from the Triticosecale group also showed a high antioxidant capacity value even if its polyphenol content was intermediate compared with others. Trifolium alexandrinum and Triticosecale had the highest value of the new index GHIC. This comparison suggests that there are important differences in fatty acid profile and polyphenol content among cheeses from goats fed grasses and legumes commonly used in the Mediterranean area. In this first approach, GHIC index, which combines the positive components found in cheese, seems to be a useful tool to provide an indication concerning the general health value of the product
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