2,697 research outputs found
An unrealistic image of science
Many UK secondary schools (ages 11-18) host Open Days for pupils in their final
year of primary school education (age 10). At these events science teachers try,
through the judicious use of a select number of practical tasks, to portray science as
being a fun, exciting and essentially a „hands on‟ activity. Whilst this approach
generates short-term situational interest amongst pupils it is ultimately an unrealistic,
and arguably unsustainable, image of science
On nonlinear viscoelastic deformations - a reappraisal of Fung's quasilinear viscoelastic model
This article offers a reappraisal of Fung's method for quasilinear
viscoelasticity. It is shown that a number of negative features exhibited in
other works, commonly attributed to the Fung approach, are merely a consequence
of the way it has been applied. The approach outlined herein is shown to yield
improved behaviour, and offers a straightforward scheme for solving a wide
range of models. Results from the new model are contrasted with those in the
literature for the case of uniaxial elongation of a bar: for an imposed stretch
of an incompressible bar, and for an imposed load. In the last case, a
numerical solution to a Volterra integral equation is required to obtain the
results. This is achieved by a high order discretisation scheme. Finally, the
stretch of a compressible viscoelastic bar is determined for two distinct
materials: Horgan-Murphy and Gent
Non-exponential relaxation and hierarchically constrained dynamics in a protein
A scaling analysis within a model of hierarchically constrained dynamics is
shown to reproduce the main features of non-exponential relaxation observed in
kinetic studies of carbonmonoxymyoglobin.Comment: 4 pages, 3 figures in text. Reference errors have been correcte
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Determinants of the application of personalised nutrition and associated technologies in dietetic practice - A mixed methods study of key stakeholders in personalised nutrition
Background: Tech-enabled personalised nutrition is an emerging area that has promise to improve health outcomes, widen access to nutrition expertise and reduce healthcare expenditure, yet uptake by registered dietitians remains low. This research programme aimed to identify levers and barriers that contribute to adoption of personalised nutrition in order to guide practice and policy for registered dietitians, educators and consumers.
Methods: A mixed methods study with a sequential exploratory design was adopted to determine what the barriers to adoption of technologies are, and secondly, what needs to be in place to make tech-enabled personalised nutrition a reality. The research programme was conducted online using qualitative (focus groups and interviews) and quantitative measures (survey and secondary analysis). Thematic analysis, statistical and secondary analyses of data were performed respectively.
Results: Using diffusion of innovation and entrepreneurial theories, findings indicate that barriers to integration of personalised nutrition technologies include intrinsic and extrinsic factors which relate to a low self-efficacy, high perception of risk, low perceived importance and usefulness of technologies to dietetic practice as well as a lack of an entrepreneurial mindset and regulatory environment.
Conclusion: Uptake of tech-enabled personalised nutrition by registered dietitians will require a multi-stakeholder approach. Educational, professional, regulatory and health policies will need to be in place and strategies that open discussion between Registered Dietitians (RD’s) at all levels are needed
Near IR luminescent rare earth 3,4,5,6-tetrafluoro-2-nitrophenoxide complexes: Synthesis, X-ray crystallography and spectroscopy
NOTICE: this is the author’s version of a work that was accepted for publication in Near IR luminescent rare earth 3,4,5,6-tetrafluoro-2-nitrophenoxide complexes: Synthesis, X-ray crystallography and spectroscopy. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Near IR luminescent rare earth 3,4,5,6-tetrafluoro-2-nitrophenoxide complexes: Synthesis, X-ray crystallography and spectroscopy, [VOL27, ISSUE5, (2008)] DOI: 10.1016/j.poly.2008.01.02
Determining phase transitions of layered oxides via electrochemical and crystallographic analysis
The chemical diffusion coefficient in LiNi1/3Mn1/3Co1/3O2 was determined via the galvanostatic intermittent titration technique in the voltage range 3 to 4.2Â V. Calculated diffusion coefficients in these layered oxide cathodes during charging and discharging reach a minimum at the open-circuit voltage of 3.8Â V and 3.7Â V vs. Li/Li+, respectively. The observed minima of the chemical diffusion coefficients indicate a phase transition in this voltage range. The unit cell parameters of LiNi1/3Mn1/3Co1/3O2 cathodes were determined at different lithiation states using ex situ crystallographic analysis. It was shown that the unit cell parameter variation correlates well with the observed values for chemical diffusion in NMC cathodes; with a notable change in absolute values in the same voltage range. We relate the observed variation in unit cell parameters to the nickel conversion into the trivalent state, which is Jahn-Teller active, and to the re-arrangement of lithium ions and vacancies
On the asymptotic properties of a canonical diffraction integral.
We introduce and study a new canonical integral, denoted I + - ε , depending on two complex parameters α 1 and α 2. It arises from the problem of wave diffraction by a quarter-plane and is heuristically constructed to capture the complex field near the tip and edges. We establish some region of analyticity of this integral in C 2 , and derive its rich asymptotic behaviour as |α 1 | and |α 2 | tend to infinity. We also study the decay properties of the function obtained from applying a specific double Cauchy integral operator to this integral. These results allow us to show that this integral shares all of the asymptotic properties expected from the key unknown function G +- arising when the quarter-plane diffraction problem is studied via a two-complex-variables Wiener-Hopf technique (see Assier & Abrahams, SIAM J. Appl. Math., in press). As a result, the integral I + - ε can be used to mimic the unknown function G +- and to build an efficient 'educated' approximation to the quarter-plane problem
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