911 research outputs found
Developing and maintaining collaborative communities of practice in Art, Design & Media: The North West Network experience
This paper describes and explores the methodologies underpinning the development of the North West Network of the Higher Education Academy's Art, Design & Media Subject Centre(ADM-HEA). Founded in 2006 the network's members are drawn from a range of institutions across the North West(NW) including pre and post '92 Universities and Further Education (FEC) Colleges with Higher Education (HE) provision. To date it has completed and disseminated two major collaborative research projects looking at research informed teaching and aspects of the student experience. The network provides opportunities for staff working at different levels, in different areas of the sector, to work together, to share good practice and to feed these experiences into teaching. It provides a model of co-operation which circumvents the problems posed by increasing competition between institutions, the difficulties presented by limited funding, and time constraints. Here, in order to promote debate about the hierarchies and perceived barriers to collaboration, are outlined the means by which the group has been sustained; the network's research has been achieved; and the ethos of the group developed. The projects outlined here demonstrate that it is possible to provide opportunities for staff working at different levels, in different areas of the sector, to work together to undertake research and to share good practice
The Cepheid Phase Lag Revisited
We compute the phase lags between the radial velocity curves and the light
curves for classical Cepheid model
sequences both in the linear and the nonlinear regimes. The nonlinear phase
lags generally fall below the linear ones except for high period models where
they lie above, and of course for low pulsation amplitudes where the two merge.
The calculated phase lags show good agreement with the available observational
data of normal amplitude Galactic Cepheids. The metallicity has but a moderate
effect on the phase lag, while the mass-luminosity relation and the parameters
of the turbulent convective model (time-dependent mixing length) mainly
influence the modal selection and the period, which is then reflected in the
period -- diagram. We discuss the potential application of this
observable as a discriminant for pulsation modes and as a test for ultra-low
amplitudes (ULA) pulsation.Comment: 11 pages, 8 figures, accepted for publication in ApJ, minor revisions
in the text and figures, (black and white version available from 2nd author's
website
Intra- and extra-cellular excretion of carboxylates
Carboxylates, such as malate and citrate, are widely acknowledged to have a central role in plant metabolism. They are involved in the production of energy and its storage as well as contributing to the cellular osmolyte pool and participating in the regulation of cellular pH. As we discuss here, recent research has demonstrated the functional importance of carboxylate excretion into the soil, apoplast and vacuole, particular with respect to the regulation of stomatal and root function
Interventions to Promote More Effective Balance-Recovery Reactions in Industrial Settings: New Perspectives on Footwear and Handrails
āChange-in-supportā balance-recovery reactions that involve rapid stepping or reaching movements play a critical role in preventing falls. Recent geriatrics studies have led to new interventions to improve ability to execute these reactions effectively. Some of these interventions have the potential to reduce fall risk for younger persons working in industrial settings. In this paper, we review research pertaining to two such interventions: 1) balance-enhancing footwear insoles designed to improve stepping reactions, and 2) proximity-triggered handrail cueing systems designed to improve reach-to-grasp reactions. The insole has a raised ridge around the perimeter that is intended to improve balance control by providing increased stimulation of sensory receptors on the footsole in situations where loss of balance may be imminent. The cueing system uses flashing lights and/or verbal prompts to attract attention to the handrail and ensure that the brain registers its location, thereby facilitating more rapid and accurate grasping of the rail if and when sudden loss of balance occurs. Results to date support the efficacy of both interventions in geriatric populations. There is also some evidence that these interventions may improve balance control in younger persons; however, further research is needed to confirm their efficacy in preventing falls in industrial settings
Polaris B, an optical companion of Polaris (alpha UMi) system: atmospheric parameters, chemical composition, distance and mass
We present an analysis of high-resolution spectroscopic observations of
Polaris B, the optical companion of the Polaris Ab system. The star has a
radial velocity V_r of -16.6km/s to -18.9km/s, and a projected rotational
velocity vsini=110 km/s. The derived atmospheric parameters are: Teff=6900K;
logg=4.3; V_t=2.5km/s. Polaris B has elemental abundances generally similar to
those of the Cepheid Polaris A (Usenko et al. 2005a), although carbon, sodium
and magnesium are close to the solar values. At a spectral type of F3V Polaris
B has a luminosity of 3.868L_sun, an absolute magnitude of +3.30mag, and a
distance of 109.5pc. The mass of the star is estimated to be 1.39M_sun, close
to a mass of 1.38+/-0.61M_sun for the recently-resolved orbital periods
companion Polaris Ab observed by Evans et al. (2007).Comment: 6 pages, 3 figures, 1 tabl
Analysis of subcellular metabolite levels of potato tubers (Solanum tuberosum) displaying alterations in cellular or extracellular sucrose metabolism
The expression of a heterologous invertase in potato tubers (Solanum tuberosum) in either the cytosol or apoplast leads to a decrease in total sucrose content and to an increase in glucose. Depending on the targeting of the enzyme different changes in phenotype and metabolism of the tubers occur: the cytosolic invertase expressing tubers show an increase in the glycolytic flux, accumulation of amino acids and organic acids, and the appearance of novel disaccharides; however, these changes are not observed when the enzyme is expressed in the apoplast [Roessner etĀ al. (2001). Plant Cell, 13, 11-29]. The analysis of these lines raised several questions concerning the regulation of compartmentation of metabolites in potato tubers. In the current study we addressed these questions by performing comparative subcellular metabolite profiling. We demonstrate that: (i) hexoses accumulate in the vacuole independently of their site of production, but that the cytosolic invertase expression led to a strong increase in the cytosolic glucose concentration and decrease in cytosolic sucrose, whereas these effects were more moderate in the apoplastic expressors; (ii) three out of four of the novel compounds found in the cytosolic overexpressors accumulate in the same compartment; (iii) despite changes in absolute cellular content the subcellular distribution of amino acids was invariant in the invertase overexpressing tubers. These results are discussed in the context of current models of the compartmentation of primary metabolism in heterotrophic plant tissues
Reddenings of FGK supergiants and classical Cepheids from spectroscopic data
Accurate and homogeneous atmospheric parameters (Teff, log (g), Vt, [Fe/H])
are derived for 74 FGK non-variable supergiants from high-resolution, high
signal-to-noise ratio, echelle spectra. Extremely high precision for the
inferred effective temperatures (10-40 K) is achieved by using the line-depth
ratio method. The new data are combined with atmospheric values for 164
classical Cepheids, observed at 675 different pulsation phases, taken from our
previously published studies. The derived values are correlated with unreddened
B-V colours compiled from the literature for the investigated stars in order to
obtain an empirical relationship of the form: (B-V)o = 57.984 - 10.3587(log
Teff)^2 + 1.67572(log Teff)^3 - 3.356(log (g)) + 0.0321(Vt) + 0.2615[Fe/H] +
0.8833((log (g))(log Teff)). The expression is used to estimate colour excesses
E(B-V) for individual supergiants and classical Cepheids, with a precision of
+-0.05 mag. for supergiants and Cepheids with n=1-2 spectra, reaching +-0.025
mag. for Cepheids with n>2 spectra, matching uncertainties for the most
sophisticated photometric techniques. The reddening scale is also a close match
to the system of space reddenings for Cepheids. The application range is for
spectral types F0--K0 and luminosity classes I and II.Comment: accepted for publication (MNRAS
Supporting the Professional Development of Early Childhood Teachers in Head Start: A Case of Acquiring Technology Proficiency
The main purpose of this paper is to describe an exemplary professional development approach in technology learning and its outcomes for early childhood teachers in Head Start in the context of a technology project. The study utilized a collage of qualitative methods including case study, ethnography, and grounded theory. Research participants were selected using purposive sampling methods, and they include 23 people who participated in the technology project. Data collection techniques included multiple, face-to-face, telephone and focus group interviews, observations, and collection of documents and artifacts related to the technology project from the participants. NVIVO qualitative data management software was used for the analysis, and the coding procedures were applied that grounded theory offered. Findings suggest that the communities of learner model of professional development supported early childhood teachersā technology learning in Head Start. The learning curve experienced by the teachers in emotional, cognitive and behavioral dimensions indicates the importance of nature of learners and supportive learning contexts in technology learning
E-grocery challenges and remedies: Global market leaders perspective
The purpose of the study is to identify logistic elements germane to e-grocery businesses, and to reveal the challenges collateral with each logistic element. Further, it strives to create a better understanding of specific remedies that have been employed by top e-grocery retailers to overcome existing challenges while aligning identified challenges with Turbanās framework. Extensive semi-structured interviews were conducted with management staff in three of the top ten global online grocery retailers and another that was a market leader in a European country. The qualitative data collected was transcribed and coded using a non-hierarchical axial coding to identify emerging themes in content analysis. The results expose a range of challenges that could be compartmentalised into three broad categories, in harmony with the different stages of the order fulfilment process. Interestingly, the study found that most challenges were operational rather than tactical or strategic in nature. While the study expands existing knowledge, its revelation that most challenges lie in the management of roles and responsibilities domain is instructive. This makes it imperative for practitioners to focus on this specific area if meaningful improvement in e-grocery retailing performance is to be realised. This research offers a systematic understanding of supply and distribution challenges, including remedies utilised to ameliorate the effect of the challenges from the perspectives of the top companies in the industry. These remedies can be invaluable for existing and emerging e-grocers
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