448 research outputs found
Hybridisation at work
This paper presents the encoding of the hybridisation method into the HETS platform.FC
A dye-fibre system from food waste: Dyeing casein fibres with anthocyanins
Regenerated protein fibres manufactured from food side-streams offer significant potential as circular and sustainable fibres, but greater knowledge of their dyeing properties is required. In this research, coloration of casein fibres with dyes also extracted from blackcurrant skins left over from juice pressing is explored. Casein fibre was dyed with blackcurrant extract, rich in anthocyanins, from pH 2 to pH 6 and from 40 to 80°C, with and without alum. Casein fibres could be dyed with blackcurrant extract across all conditions tested, and under optimal conditions, dyeing is achieved with medium depths of colour with good wash fastness. Highest sorption of anthocyanins onto casein is observed at pH 4, where anthocyanins are a mixture of 60% neutral purple quinonoidal base form and 40% flavylium cation form; under these conditions dye–fibre interaction is optimal. At pH 2, casein fibre has a highly positively charged surface and anthocyanin is in the flavylium cation form, leading to some dye–fibre repulsion. At pH 6, the slightly negatively charged casein fibre demonstrates lower sorption of the mixture of 40% purple quinonoidal base form and 60% the anionic quinonoidal base form, again leading to some dye–fibre repulsion. Presence of alum in the dyebath enhances sorption of anthocyanins onto fibre at pH 4 due to formation of Al–anthocyanin complexes. Wash fastness of the dyeings is better as pH increases and as temperature increases
Constrained optimised flexible power control for grid-connected converters under unbalanced faults
This paper presents a constrained multi-objective optimisation scheme for a grid-connected voltage source converter operating under unbalanced voltage conditions in a three-phase three-wire system. The scheme is aimed at evaluating the converter reference currents required to supply all the power generated by the connected source to the grid, whilst simultaneously suppressing oscillations of both real and reactive powers. The trade-off between these two conflicting requirements is achieved by setting a single cost function with variable weightings. Two constraints are set to restrict the converter instantaneous phase current and maintain low DC-bus voltage percentage ripple. A genetic algorithm is applied to search for the optimal solution. Simulation results are presented and confirm the effectiveness of the proposed method
Kinks in the Presence of Rapidly Varying Perturbations
Dynamics of sine-Gordon kinks in the presence of rapidly varying periodic
perturbations of different physical origins is described analytically and
numerically. The analytical approach is based on asymptotic expansions, and it
allows to derive, in a rigorous way, an effective nonlinear equation for the
slowly varying field component in any order of the asymptotic procedure as
expansions in the small parameter , being the frequency
of the rapidly varying ac driving force. Three physically important examples of
such a dynamics, {\em i.e.}, kinks driven by a direct or parametric ac force,
and kinks on rotating and oscillating background, are analysed in detail. It is
shown that in the main order of the asymptotic procedure the effective equation
for the slowly varying field component is {\em a renormalized sine-Gordon
equation} in the case of the direct driving force or rotating (but phase-locked
to an external ac force) background, and it is {\em the double sine-Gordon
equation} for the parametric driving force. The properties of the kinks
described by the renormalized nonlinear equations are analysed, and it is
demonstrated analytically and numerically which kinds of physical phenomena may
be expected in dealing with the renormalized, rather than the unrenormalized,
nonlinear dynamics. In particular, we predict several qualitatively new effects
which include, {\em e.g.}, the perturbation-inducedComment: New copy of the paper of the above title to replace the previous one,
lost in the midst of the bulletin board. RevTeX 3.
Ruthenium(II) dichloro or dithiocyanato complexes with 4,4′:2′,2″:4″,4‴-quaterpyridinium ligands:Towards photosensitisers with enhanced low-energy absorption properties
Fourteen new complexes of the form cis-\[RuIIX2(R2qpy2+)2]4+ (R2qpy2+ = a 4,4′:2′,2″:4″,4‴-quaterpyridinium ligand, X = Cl− or NCS−) have been prepared and isolated as their PF6− salts. Characterisation involved various techniques including 1H NMR spectroscopy and +electrospray or MALDI mass spectrometry. The UV–Vis spectra display intense intraligand π → π∗ absorptions, and also metal-to-ligand charge-transfer (MLCT) bands with two resolved maxima in the visible region. Red-shifts in the MLCT bands occur as the electron-withdrawing strength of the pyridinium groups increases, while replacing Cl− with NCS− causes blue-shifts. Cyclic voltammograms show quasi-reversible or reversible RuIII/II oxidation waves, and several ligand-based reductions that are irreversible. The variations in the redox potentials correlate with changes in the MLCT energies. A single-crystal X-ray structure has been obtained for a protonated form of a proligand salt, \[(4-(CO2H)Ph)2qpyH3+]\[HSO4]3·3H2O. Time-dependent density functional theory calculations give adequate correlations with the experimental UV–Vis spectra for the two carboxylic acid-functionalised complexes in DMSO. Despite their attractive electronic absorption spectra, these dyes are relatively inefficient photosensitisers on electrodes coated with TiO2 or ZnO. These observations are attributed primarily to weak electronic coupling with the surfaces, since the DFT-derived LUMOs include no electron density near the carboxylic acid anchors
Unification of multi-species vertebrate anatomy ontologies for comparative biology in Uberon.
BACKGROUND: Elucidating disease and developmental dysfunction requires understanding variation in phenotype. Single-species model organism anatomy ontologies (ssAOs) have been established to represent this variation. Multi-species anatomy ontologies (msAOs; vertebrate skeletal, vertebrate homologous, teleost, amphibian AOs) have been developed to represent 'natural' phenotypic variation across species. Our aim has been to integrate ssAOs and msAOs for various purposes, including establishing links between phenotypic variation and candidate genes.
RESULTS: Previously, msAOs contained a mixture of unique and overlapping content. This hampered integration and coordination due to the need to maintain cross-references or inter-ontology equivalence axioms to the ssAOs, or to perform large-scale obsolescence and modular import. Here we present the unification of anatomy ontologies into Uberon, a single ontology resource that enables interoperability among disparate data and research groups. As a consequence, independent development of TAO, VSAO, AAO, and vHOG has been discontinued.
CONCLUSIONS: The newly broadened Uberon ontology is a unified cross-taxon resource for metazoans (animals) that has been substantially expanded to include a broad diversity of vertebrate anatomical structures, permitting reasoning across anatomical variation in extinct and extant taxa. Uberon is a core resource that supports single- and cross-species queries for candidate genes using annotations for phenotypes from the systematics, biodiversity, medical, and model organism communities, while also providing entities for logical definitions in the Cell and Gene Ontologies. THE ONTOLOGY RELEASE FILES ASSOCIATED WITH THE ONTOLOGY MERGE DESCRIBED IN THIS MANUSCRIPT ARE AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases/2013-02-21/ CURRENT ONTOLOGY RELEASE FILES ARE AVAILABLE ALWAYS AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases
Building Community in the HIV Online Intervention Space: Lessons From the HealthMPowerment Intervention
Background: Mobile health platforms can facilitate social support and address HIV (human immunodeficiency virus) stigma but pose challenges for intervention design and participant engagement. Giddens’s structuration theory, that individuals are shaped by—and shape—their communities through rules and resources that give them power to operate within these environments, provides a useful analytic framework for exploring these dynamic intervention spaces. Method: Data were drawn from an online randomized controlled trial intervention (HealthMpowerment) for young Black men who have sex with men to reduce condomless anal intercourse. We applied a conversational analysis informed by structuration theory to 65 user-generated conversations that included stigma content. We aimed to understand how the interdependent relationship between the intervention space and participants’ contributions might contribute to behavior change. Results: Thirty five intervention participants contributed to the analyzed conversations. Our analysis identified three types of conversational processes that may underlie behavior change: (1) Through intervention engagement, participants established norms and expectations that shaped their discussions; (2) participants used anecdotes and anonymity to reinforce norms; and (3) intervention staff members sought to improve engagement and build knowledge by initiating discussions and correcting misinformation, thus playing an integral role in the online community. Conclusions: The lens of structuration theory usefully reveals potential behavior change mechanisms within the social interactions of an online intervention. Future design of these interventions to address HIV stigma should explicitly characterize the context in which individuals (study staff and participants) engage with one another in order to assess whether these processes are associated with improved intervention outcomes
Multi- Configurations
Using resonant x-ray scattering to perform diffraction experiments at the U
M edge novel reflections of the generic form have been observed
in UAs$_{0.8}$Se$_{0.2}$ where $\vec{k} = $, with $k = {1/2}$ reciprocal
lattice units, is the wave vector of the primary (magnetic) order parameter.
The reflections, with of the magnetic intensities,
cannot be explained on the basis of the primary order parameter within standard
scattering theory. A full experimental characterisation of these reflections is
presented including their energy, azimuthal and temperature dependencies. On
this basis we establish that the reflections most likely arise from the
electric dipole operator involving transitions between the core 3d and
partially filled $5f$ states. The temperature dependence couples the
peak to the triple- region of the phase diagram: Below K,
where previous studies have suggested a transition to a double- state,
the intensity of the is dramatically reduced. Whilst we are unable to
give a definite explanation of how these novel reflections appear, this paper
concludes with a discussion of possible ideas for these reflections in terms of
the coherent superposition of the 3 primary (magnetic) order parameters
Detector Description and Performance for the First Coincidence Observations between LIGO and GEO
For 17 days in August and September 2002, the LIGO and GEO interferometer
gravitational wave detectors were operated in coincidence to produce their
first data for scientific analysis. Although the detectors were still far from
their design sensitivity levels, the data can be used to place better upper
limits on the flux of gravitational waves incident on the earth than previous
direct measurements. This paper describes the instruments and the data in some
detail, as a companion to analysis papers based on the first data.Comment: 41 pages, 9 figures 17 Sept 03: author list amended, minor editorial
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