2,231 research outputs found
The lived experience of juvenile idiopathic arthritis in young people receiving etanercept
BACKGROUND: This study explores young people's daily experiences of living with Juvenile Idiopathic Arthritis (JIA) and their thoughts, beliefs and feelings related to the biological drug Etanercept, prescribed as part of their treatment. METHODS: An Interpretive Phenomenological approach was used to allow in-depth examinations of the young people's personal accounts of their lived experiences. Data were obtained from 6 young people between the ages of 10-13 years, from one tertiary institution's Paediatric Rheumatology department using audio-taped open-ended interviews. RESULTS: The transcripts yielded seven thousand words of data and two hundred significant statements, which were reduced to five themes; 1) Who understands me, 2) Medicines and injections, 3) Challenges of schooling and friendships, 4) Being different, and 5) Exclusion from sports. There were marked similarities between the young people's statements; however, there were also some striking differences. The theme 'Who understands me' yielded the biggest section of data, but also produced the biggest disparity between the young people. Two patients were very clear that they thought everyone 'understands', whilst two other patients held the belief that 'no one understood'. This paper explores these statements in further detail. CONCLUSIONS: The findings from this study can give healthcare professionals novel insight into the likely reactions to treatment for JIA and, through this, enable them to offer improved support, education and early intervention before these issues become a concern. This study also provides insight into the emotional resilience of young people with JIA
HST followup observations of two bright z ~ 8 candidate galaxies from the BoRG pure-parallel survey
We present followup imaging of two bright (L > L*) galaxy candidates at z > 8
from the Brightest of Reionizing Galaxies (BoRG) survey with the F098M filter
on HST/WFC3. The F098M filter provides an additional constraint on the flux
blueward of the spectral break, and the observations are designed to
discriminate between low- and high-z photometric redshift solutions for these
galaxies. Our results confirm one galaxy, BoRG 0116+1425 747, as a highly
probable z ~ 8 source, but reveal that BoRG 0116+1425 630 - previously the
brightest known z > 8 candidate (mAB = 24.5) - is likely to be a z ~ 2
interloper. As this source was substantially brighter than any other z > 8
candidate, removing it from the sample has a significant impact on the derived
UV luminosity function in this epoch. We show that while previous BoRG results
favored a shallow power-law decline in the bright end of the luminosity
function prior to reionization, there is now no evidence for departure from a
Schechter function form and therefore no evidence for a difference in galaxy
formation processes before and after reionization.Comment: Accepted by ApJL, 7 pages, 4 figure
Kinematic dynamo action in a sphere: Effects of periodic time-dependent flows on solutions with axial dipole symmetry
Choosing a simple class of flows, with characteristics that may be present in
the Earth's core, we study the ability to generate a magnetic field when the
flow is permitted to oscillate periodically in time. The flow characteristics
are parameterised by D, representing a differential rotation, M, a meridional
circulation, and C, a component characterising convective rolls. Dynamo action
is sensitive to these flow parameters and fails spectacularly for much of the
parameter space where magnetic flux is concentrated into small regions.
Oscillations of the flow are introduced by varying the flow parameters in
time, defining a closed orbit in the space (D,M). Time-dependence appears to
smooth out flux concentrations, often enhancing dynamo action. Dynamo action
can be impaired, however, when flux concentrations of opposite signs occur
close together as smoothing destroys the flux by cancellation.
It is possible to produce geomagnetic-type reversals by making the orbit
stray into a region where the steady flows generate oscillatory fields. In this
case, however, dynamo action was not found to be enhanced by the
time-dependence.
A novel approach is taken to solving the time-dependent eigenvalue problem,
where by combining Floquet theory with a matrix-free Krylov-subspace method we
avoid large memory requirements for storing the matrix required by the standard
approach.Comment: 22 pages, 12 figures. Geophys. Astrophys. Fluid Dynam., as accepted
(2004
New insights into the regulatory pathways associated with the activation of the stringent response in bacterial resistance to the PBP2-targeted antibiotics, mecillinam and OP0595/RG6080
Objectives: The diazabicyclooctane β-lactamase inhibitor OP0595 (RG6080) also acts as an antibiotic, targeting PBP2 in Enterobacteriaceae, but this activity is vulnerable to mutational resistance. We used WGS to investigate the basis of this resistance. Methods: Twenty OP0595-selected mutants, comprising four derived from each of five different Escherichia coli strains, were sequenced on Illumina HiSeq. Reads from each mutant were mapped to the assembled genome of the corresponding parent. A variant-calling file generated with Samtools was parsed to determine genetic alterations. Results: Besides OP0595, the mutants consistently showed decreased susceptibility to mecillinam, which likewise targets PBP2, and grew as stable round forms in the presence of subinhibitory concentrations of OP0595. Among the 20 mutants, 18 had alterations in genes encoding tRNA synthase and modification functions liable to induce expression of the RpoS sigma factor through activation of the stringent response or had mutations suppressing inactivators of RpoS or the stringent response signal-degrading enzyme, SpoT. TolB was inactivated in one mutant: this activates RcsBC regulation and was previously associated with mecillinam resistance. The mechanism of resistance remained unidentified in one mutant. Both the RpoS and RcsBC systems regulate genes of cell division, including ftsAQZ that can compensate for loss or inhibition of PBP2, allowing survival of the challenged bacteria as stable round forms, as seen. Conclusions: WGS identified the global stringent response signal, entailing induction of RpoS, as the main mediator of mutational resistance to OP0595 in E. coli
Star Formation at z=2.481 in the Lensed Galaxy SDSS J1110+6459: Star Formation down to 30 parsec scales
We present measurements of the surface density of star formation, the
star-forming clump luminosity function, and the clump size distribution
function, for the lensed galaxy SGAS J111020.0+645950.8 at a redshift of
z=2.481. The physical size scales that we probe, radii r=30--50 pc, are
considerably smaller scales than have yet been studied at these redshifts. The
star formation surface density we find within these small clumps is consistent
with surface densities measured previously for other lensed galaxies at similar
redshift. Twenty-two percent of the rest-frame ultraviolet light in this lensed
galaxy arises from small clumps, with r<100 pc. Within the range of overlap,
the clump luminosity function measured for this lensed galaxy is remarkably
similar to those of z~0 galaxies. In this galaxy, star-forming regions smaller
than 100 pc---physical scales not usually resolved at these redshifts by
current telescopes---are important locations of star formation in the distant
universe. If this galaxy is representative, this may contradict the theoretical
picture in which the critical size scale for star formation in the distant
universe is of order 1 kiloparsec. Instead, our results suggest that current
telescopes have not yet resolved the critical size scales of star-forming
activity in galaxies over most of cosmic time
Full sphere hydrodynamic and dynamo benchmarks
Convection in planetary cores can generate fluid flow and magnetic fields, and a number of sophisticated codes exist to simulate the dynamic behaviour of such systems. We report on the first community activity to compare numerical results of computer codes designed to calculate fluid flow within a whole sphere. The flows are incompressible and rapidly rotating and the forcing of the flow is either due to thermal convection or due to moving boundaries. All problems defined have solutions that allow easy comparison, since they are either steady, slowly drifting or perfectly periodic. The first two benchmarks are defined based on uniform internal heating within the sphere under the Boussinesq approximation with boundary conditions that are uniform in temperature and stress-free for the flow. Benchmark 1 is purely hydrodynamic, and has a drifting solution. Benchmark 2 is a magnetohydrodynamic benchmark that can generate oscillatory, purely periodic, flows and magnetic fields. In contrast, Benchmark 3 is a hydrodynamic rotating bubble benchmark using no slip boundary conditions that has a stationary solution. Results from a variety of types of code are reported, including codes that are fully spectral (based on spherical harmonic expansions in angular coordinates and polynomial expansions in radius), mixed spectral and finite difference, finite volume, finite element and also a mixed Fourier–finite element code. There is good agreement between codes. It is found that in Benchmarks 1 and 2, the approximation of a whole sphere problem by a domain that is a spherical shell (a sphere possessing an inner core) does not represent an adequate approximation to the system, since the results differ from whole sphere results
The bright-end galaxy candidates at z ~ 9 from 79 independent HST fields
We present a full data analysis of the pure-parallel Hubble Space Telescope
(HST) imaging observations in the Brightest of Reionizing Galaxies Survey
(BoRG[z9]) in Cycle 22. The medium-deep exposures with five HST/WFC3IR+UVIS
filter bands from 79 independent sightlines (~370 arcmin^2) provide the least
biased determination of number density for z>9 bright galaxies against cosmic
variance. After a strict two-step selection for candidate galaxies, including
dropout color and photometric redshift analyses, and revision of previous BoRG
candidates, we identify one source at z~10 and two sources at z~9. The z~10
candidate shows evidence of line-of-sight lens magnification (mu~1.5), yet it
appears surprisingly luminous (MUV ~ -22.6\pm0.3 mag), making it one of the
brightest candidates at z > 8 known (~ 0.3 mag brighter than the z = 8.68
galaxy EGSY8p7, spectroscopically confirmed by Zitrin and collaborators). For z
~ 9 candidates, we include previous data points at fainter magnitudes and find
that the data are well fitted by a Schechter luminosity function with alpha ~
-2.1, MUV ~ -21.5 mag, and log phi ~ -4.5 Mpc^-3mag^-1, for the first time
without fixing any parameters. The inferred cosmic star formation rate density
is consistent with unaccelerated evolution from lower redshift.Comment: 18pages, 7figures, 6tables. accepted to the Astrophysical Journa
Direct Measurement of the Destruction of Charge Quantization in a Single Electron Box
We report here direct measurements of the destruction of charge quantization
in a single electron box, the first over the full range of box-to-lead
conductance values from G ~ 0 to the conductance quantum G_q = 2e^2/h, using a
sensitive single-electron transistor (SET) electrometer. The sensitivity of the
electrometer is measured to be dq ~ 6 x 10^-5 e/sqrt{Hz} and its superiority to
conductance measurements of charge fluctuations is clearly demonstrated. As the
rate of quantum mechanical tunneling from the box to its lead is increased, the
quantization of charge is destroyed, disappearing entirely at G = G_q in
agreement with theory.Comment: 9 pages, 4 figures, to be published in Applied Physics Letter
A randomised controlled trial of PEGASUS, a psychoeducational programme for young people with high-functioning autism spectrum disorder.
Psychoeducation is an essential component of postdiagnostic care for people with ASD (autism spectrum disorder), but there is currently no evidence base for clinical practice. We designed, manualised and evaluated PEGASUS (psychoeducation group for autism spectrum understanding and support), a group psychoeducational programme aiming to enhance the self-awareness of young people with ASD by teaching them about their diagnosis
Superposition of photon- and phonon- assisted tunneling in coupled quantum dots
We report on electron transport through an artificial molecule formed by two
tunnel coupled quantum dots, which are laterally confined in a two-dimensional
electron system of an AlGaAs/GaAs heterostructure. Coherent
molecular states in the coupled dots are probed by photon-assisted tunneling
(PAT). Above 10 GHz, we observe clear PAT as a result of the resonance between
the microwave photons and the molecular states. Below 8 GHz, a pronounced
superposition of phonon- and photon-assisted tunneling is observed. Coherent
superposition of molecular states persists under excitation of acoustic
phonons.Comment: 5 pages, 4 figure
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