3,285 research outputs found
Imagining and producing the 'good' migrant: the role of recruitment agencies in shaping bodily goodness
This paper focuses on representations of labour migrants and interrogates how such imaginaries shape migrant recruitment and employment regimes. The recruitment and employment of labour migrants inevitably involves a range of knowledge practices which affect who is recruited, from where and for what purposes. In particular this paper seeks to advance understandings of how images of âbodily goodnessâ are represented graphically and how perceptions of migrant workers influence the recruitment of workers from Latvia. The analysis results in a schema of the âfilteringâ processes that are enacted to âproduceâ the âidealâ migrant worker
Spectroscopic imaging of single atoms within a bulk solid
The ability to localize, identify and measure the electronic environment of
individual atoms will provide fundamental insights into many issues in
materials science, physics and nanotechnology. We demonstrate, using an
aberration-corrected scanning transmission microscope, the spectroscopic
imaging of single La atoms inside CaTiO3. Dynamical simulations confirm that
the spectroscopic information is spatially confined around the scattering atom.
Furthermore we show how the depth of the atom within the crystal may be
estimated.Comment: 4 pages and 3 figures. Accepted in Phys.Rev.Let
Metastable phases and "metastable" phase diagrams
The work discusses specifics of phase transitions for metastable states of
substances. The objects of condensed media physics are primarily equilibrium
states of substances with metastable phases viewed as an exception, while the
overwhelming majority of organic substances investigated in chemistry are
metastable. It turns out that at normal pressure many of simple molecular
compounds based on light elements (these include: most hydrocarbons; nitrogen
oxides, hydrates, and carbides; carbon oxide (CO); alcohols, glycerin etc) are
metastable substances too, i.e. they do not match the Gibbs' free energy
minimum for a given chemical composition. At moderate temperatures and
pressures, the phase transitions for given metastable phases throughout the
entire experimentally accessible time range are reversible with the equilibrium
thermodynamics laws obeyed. At sufficiently high pressures (1-10 GPa), most of
molecular phases irreversibly transform to more energy efficient polymerized
phases, both stable and metastable. These transformations are not consistent
with the equality of the Gibbs' free energies between the phases before and
after the transition, i.e. they are not phase transitions in "classical"
meaning. The resulting polymeric phases at normal pressure can exist at
temperatures above the melting one for the initial metastable molecular phase.
Striking examples of such polymers are polyethylene and a polymerized
modification of CO. Many of energy-intermediate polymeric phases can apparently
be synthesized by the "classical" chemistry techniques at normal pressure.Comment: 5 pages, 4 figure
Identification, surveillance and management of Aedes vexans in a flooded river valley in Nottinghamshire, United Kingdom
Posttranslational processing of concanavalin A precursors in jackbean cotyledons
Metabolic labeling of immature jackbean cotyledons with 14C-amino acids was used to determine the processing steps involved in the assembly of concanavalin A. Pulse-chase experiments and analyses of immunoprecipitated lectin forms indicated a complex series of events involving seven distinct species. The structural relatedness of all of the intermediate species was confirmed by two-dimensional mapping of 125I-tryptic peptides. An initial glycosylated precursor was deglycosylated and cleaved into smaller polypeptides, which subsequently reannealed over a period of 10-27 h. NH2-terminal sequencing of the abundant precursors confirmed that the intact subunit of concanavalin A was formed by the reannealing of two fragments, since the alignment of residues 1-118 and 119-237 was reversed in the final form of the lectin identified in the chase and the precursor first labeled. When the tissue was pulse-chased in the presence of monensin, processing of the glycosylated precursor was inhibited. The weak bases NH4Cl and chloroquine were without effect. Immunocytochemical studies showed that monensin treatment caused the accumulation of immunoreactive material at the cell surface and indicated that the ionophore had induced the secretion of a component normally destined for deposition within the protein bodies. Consideration of the tertiary structure of the glycosylated precursor and mature lectin showed that the entire series of processing events could occur without significant refolding of the initial translational product. Proteolytic events included removal of a peptide from the surface of the precursor molecule that connected the NH2- and COOH-termini of the mature protein. This processing activated the carbohydrate-binding activity of the lectin. The chase data suggest the occurrence of a simultaneous cleavage and formation of a peptide bond, raising the possibility that annealment of the fragments to give rise to the mature subunit involves a transpeptidation event rather than cleavage and subsequent religation
Shine 2014 Final Report: Social Prescribing: integrating GP and Community Assets for Health
Commissioned by City and Hackney Clinical Commissioning Group, in partnership with the University of East London and Queen Mary University of London
Three-Dimensional FDTD Simulation of Biomaterial Exposure to Electromagnetic Nanopulses
Ultra-wideband (UWB) electromagnetic pulses of nanosecond duration, or
nanopulses, have been recently approved by the Federal Communications
Commission for a number of various applications. They are also being explored
for applications in biotechnology and medicine. The simulation of the
propagation of a nanopulse through biological matter, previously performed
using a two-dimensional finite difference-time domain method (FDTD), has been
extended here into a full three-dimensional computation. To account for the UWB
frequency range, a geometrical resolution of the exposed sample was ,
and the dielectric properties of biological matter were accurately described in
terms of the Debye model. The results obtained from three-dimensional
computation support the previously obtained results: the electromagnetic field
inside a biological tissue depends on the incident pulse rise time and width,
with increased importance of the rise time as the conductivity increases; no
thermal effects are possible for the low pulse repetition rates, supported by
recent experiments. New results show that the dielectric sample exposed to
nanopulses behaves as a dielectric resonator. For a sample in a cuvette, we
obtained the dominant resonant frequency and the -factor of the resonator.Comment: 15 pages, 8 figure
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