573 research outputs found
Self-care Barriers Reported by Emergency Department Patients With Acute Heart Failure: A Sociotechnical Systems-based Approach
Study objective
We pilot tested a sociotechnical systems-based instrument that assesses the prevalence and nature of self-care barriers among patients presenting to the emergency department (ED) with acute heart failure.
Methods
A semistructured instrument for measuring self-reported self-care barriers was developed and administered by ED clinicians and nonclinician researchers to 31 ED patients receiving a diagnosis of acute heart failure. Responses were analyzed with descriptive statistics and qualitative content analysis. Feasibility was assessed by examining participant cooperation rates, instrument completion times, item nonresponse, and data yield.
Results
Of 47 distinct self-care barriers assessed, a median of 15 per patient were indicated as “sometimes” or “often” present. Thirty-four specific barriers were reported by more than 25% of patients and 9 were reported by more than 50%. The sources of barriers included the person, self-care tasks, tools and technologies, and organizational, social, and physical contexts. Seven of the top 10 most prevalent barriers were related to patient characteristics; the next 3, to the organizational context (eg, life disruptions). A preliminary feasibility assessment found few item nonresponses or comprehension difficulties, good cooperation, and high data yield from both closed- and open-ended items, but also found opportunities to reduce median administration time and variability.
Conclusion
An instrument assessing self-care barriers from multiple system sources can be feasibly implemented in the ED. Further research is required to modify the instrument for widespread use and evaluate its implementation across institutions and cultural contexts. Self-care barriers measurement can be one component of broader inquiry into the distributed health-related “work” activity of patients, caregivers, and clinicians
Papermaking at Hayle Mill
65 pages, 1 unnumbered leaf of plates : illustrations, samples, 1 folded map. Includes a book, Papermaking at Hayle Mill, 1808-1987 by Maureen Green; a map, The Loose Valley, 1856 with the mills on Loose Stream; Mill photographs; Sample papers; and 12 proof sheets for the book; all issued in a box. Printed in black, red, and blue. Contents printed inside the box: Hayle Mill book -- Loose Valley map -- Mill photographs -- Sample papers. Printed on Finale, the last paper made at Hayle Mill. ... The portrait of Samuel Green was prepared and printed on Epson Archival paper by Ellen Dorn Levitt who also scanned the watermarks and maps preparing them, with Claire Van Vliet, for platemaking. Much of the letterpress printing used polymer plates from Boxcar Press ... and was printed by Andrew Miller-Brown. ... the photographs were scanned by Ellen Dorn Levitt from old prints in the Hayle Mill Archive and cleaned up in Photoshop. They were printed by Emily Corrow on a Xerox Docucolor 240 copier in Hammermill 100lb archival cover copy paper --Colophon of book. Exposed stitch binding. Two color fabric covering on clamshell box, title printed on paper, mounted on box spine. Gift of the Museum on behalf of the original donor, Ruth Fine. Curated title for Fleet Library Special Collections exhibition By Hand: Women & Books Exhibit fall, 2021.https://digitalcommons.risd.edu/specialcollections_books_printmaking/1003/thumbnail.jp
Evolution of the Early-Type Galaxy Fraction in Clusters since z = 0.8
We study the morphological content of a large sample of high-redshift
clusters to determine its dependence on cluster mass and redshift. Quantitative
morphologies are based on bulge+disk decompositions of cluster and field
galaxies on deep VLT/FORS2 images of 18 optically-selected clusters at 0.45 < z
< 0.80 from the ESO Distant Cluster Survey (EDisCS). Morphological content is
given by the early-type galaxy fraction f_et, and early-type galaxies are
selected based on their bulge fraction and image smoothness. A set of 158 SDSS
clusters is analyzed exactly as the EDisCS sample to provide a robust local
comparison. Our main results are: (1) f_et values for the SDSS and EDisCS
clusters exhibit no clear trend as a function of sigma. (2) Mid-z EDisCS
clusters around sigma = 500 km/s have f_et ~= 0.5 whereas high-z EDisCS
clusters have f_et ~= 0.4 (~25% increase over 2 Gyrs). (3) There is a marked
difference in the morphological content of EDisCS and SDSS clusters. None of
the EDisCS clusters have f_et greater than 0.6 whereas half of the SDSS
clusters lie above this value. This difference is seen in clusters of all
velocity dispersions. (4) There is a strong correlation between morphology and
star formation in SDSS and EDisCS clusters. This correlation holds independent
of sigma and z even though the fraction of [OII] emitters decreases from z~0.8
to z~0.06 in all environments. Our results pose an interesting challenge to
structural transformation and star formation quenching processes that strongly
depend on the global cluster environment and suggest that cluster membership
may be of lesser importance than other variables in determining galaxy
properties. (ABRIDGED)Comment: 22 pages, 10 figures, accepted for publication in A&
LoCuSS: The mid-infrared Butcher-Oemler effect
We study the mid-infrared (MIR) properties of galaxies in 30 massive galaxy
clusters at 0.02<z<0.40, using panoramic Spitzer/MIPS 24micron and NIR data.
This is the largest sample of clusters to date with MIR data covering not only
the cluster cores, but extending into the infall regions. We revisit the
Butcher-Oemler effect, measuring the fraction of massive infrared-luminous
galaxies (K5x10^10L_sun) within r_200, finding a steady increase
in the fraction with redshift from ~3% at z=0.02 to ~10% by z=0.30, and an rms
cluster-to-cluster scatter about this trend of 0.03. The best-fit redshift
evolution model is of the form f_SF ~ (1+z)^5.7, which is stronger redshift
evolution than that of L*_IR in both clusters and the field. We find that,
statistically, this excess is associated with galaxies found at large
cluster-centric radii, implying that the MIR Butcher-Oemler effect can be
explained by a combination of both the global decline in star-formation in the
universe since z~1 and enhanced star formation in the infall regions of
clusters at intermediate redshifts. This picture is supported by a simple
infall model based on the Millennium Simulation semi-analytic galaxy catalogs,
whereby star-formation in infalling galaxies is instantaneously quenched upon
their first passage through the cluster, in that the observed radial trends of
f_SF trace those inferred from the simulations. We also find that f_SF does not
depend on simple indicators of the dynamical state of clusters, including the
offset between the brightest cluster galaxy and the peak of the X-ray emission.
This is consistent with the picture described above in that most new
star-formation in clusters occurs in the infall regions, and is thus not
sensitive to the details of cluster-cluster mergers in the core regions.Comment: 11 pages, 7 figures, accepted for publication in Ap
Thermal Impact on Spiking Properties in Hodgkin-Huxley Neuron with Synaptic Stimulus
The effect of environmental temperature on neuronal spiking behaviors is
investigated by numerically simulating the temperature dependence of spiking
threshold of the Hodgkin-Huxley neuron subject to synaptic stimulus. We find
that the spiking threshold exhibits a global minimum in a "comfortable
temperature" range where spike initiation needs weakest synaptic strength,
indicating the occurrence of optimal use of synaptic transmission in neural
system. We further explore the biophysical origin of this phenomenon in ion
channel gating kinetics and also discuss its possible biological relevance in
information processing in neural systems.Comment: 10 pages, 4 figure
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A stronger role for long-term moisture change than for CO<sub>2</sub> in determining tropical woody vegetation change
Anthropogenically elevated CO2 (eCO2) concentrations have been suggested to increase woody cover within tropical ecosystems through fertilization. The effect of eCO2 is built into Earth system models, although testing the relationship over long periods remains challenging. Here, we explore the relative importance of six drivers of vegetation change in western Africa over the past ~500,000 years (moisture availability, fire activity, mammalian herbivore density, temperature, temperature seasonality, CO2) by coupling past environmental change data from Lake Bosumtwi (Ghana) with global data. We found that moisture availability and fire activity were the most important factors in determining woody cover, whereas the effect of CO2 was small. Our findings suggest that the role of eCO2 effects on tropical vegetation in predictive models must be reconsidered
LoCuSS: Luminous infrared galaxies in the merging cluster Abell 1758 at z=0.28
We present the first galaxy evolution results from the Local Cluster
Substructure Survey (LoCuSS), a multi-wavelength survey of 100 X-ray selected
galaxy clusters at 0.15<z<0.30. LoCuSS combines far-UV through far-IR
observations of cluster galaxies with gravitational lensing analysis and X-ray
data to investigate the interplay between the hierarchical assembly of clusters
and the evolution of cluster galaxies. Here we present new panoramic
Spitzer/MIPS 24micron observations of the merging cluster Abell 1758 at z=0.279
spanning 6.5x6.5Mpc and reaching a 90% completeness limit of 400uJy. We
estimate a global cluster SFR of 910\pm320 M_sun/yr within 3 Mpc of the cluster
centre, originating from 42 galaxies with L_IR > 5x10^10 L_sun. The obscured
activity in A1758 is therefore comparable with that in Cl 0024+1654, the most
active cluster previously studied at 24um. The obscured galaxies faithfully
trace the cluster potential as revealed by the weak-lensing mass map of the
cluster, including numerous mass peaks at R~2-3Mpc that are likely associated
with infalling galaxy groups and filamentary structures. However the core
(R<500kpc) of A1758N is 2x more active in the IR than that of A1758S, likely
reflecting differences in the recent dynamical history of the two clusters. The
24micron results from A1758 therefore suggest that dust-obscured cluster
galaxies are common in merging clusters and suggests that obscured activity in
clusters is triggered by both the details of cluster-cluster mergers and
processes that operate at larger radii including those within in-falling
groups. Our ongoing far-UV through far-IR observations of a large sample of
clusters should allow us to disentangle the different physical processes
responsible for triggering obscured star formation in clusters.Comment: 13 pages, 9 figures. Accepted for publication in MNRA
Photo-antagonism of the GABAA receptor
Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor β and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation
The XMM Cluster Survey: Forecasting cosmological and cluster scaling-relation parameter constraints
We forecast the constraints on the values of sigma_8, Omega_m, and cluster
scaling relation parameters which we expect to obtain from the XMM Cluster
Survey (XCS). We assume a flat Lambda-CDM Universe and perform a Monte Carlo
Markov Chain analysis of the evolution of the number density of galaxy clusters
that takes into account a detailed simulated selection function. Comparing our
current observed number of clusters shows good agreement with predictions. We
determine the expected degradation of the constraints as a result of
self-calibrating the luminosity-temperature relation (with scatter), including
temperature measurement errors, and relying on photometric methods for the
estimation of galaxy cluster redshifts. We examine the effects of systematic
errors in scaling relation and measurement error assumptions. Using only (T,z)
self-calibration, we expect to measure Omega_m to +-0.03 (and Omega_Lambda to
the same accuracy assuming flatness), and sigma_8 to +-0.05, also constraining
the normalization and slope of the luminosity-temperature relation to +-6 and
+-13 per cent (at 1sigma) respectively in the process. Self-calibration fails
to jointly constrain the scatter and redshift evolution of the
luminosity-temperature relation significantly. Additional archival and/or
follow-up data will improve on this. We do not expect measurement errors or
imperfect knowledge of their distribution to degrade constraints significantly.
Scaling-relation systematics can easily lead to cosmological constraints 2sigma
or more away from the fiducial model. Our treatment is the first exact
treatment to this level of detail, and introduces a new `smoothed ML' estimate
of expected constraints.Comment: 28 pages, 17 figures. Revised version, as accepted for publication in
MNRAS. High-resolution figures available at http://xcs-home.org (under
"Publications"
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