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Psychological distress after stroke and aphasia: the first six months
Objective: We explored the factors that predicted psychological distress in the first six months post stroke in a sample including people with aphasia.
Design: Prospective longitudinal observational study.
Setting and subjects: Participants with a first stroke from two acute stroke units were assessed while still in hospital (baseline) and at three and six months post stroke.
Main measures: Distress was assessed with the General Health Questionnaire-12. Other measures included: NIH Stroke Scale, Barthel Index, Frenchay Aphasia Screening Test, Frenchay Activities Index, MOS Social Support Scale and social network indicators. Logistic regression was used to identify predictors of distress at each stage post stroke; and to determine what baseline factors predicted distress at six months.
Results: Eighty-seven participants were able to self-report on measures used, of whom 32 (37%) had aphasia. 71 (82%) were seen at six months, including 11 (16%) with aphasia. Predictors of distress were: stroke severity at baseline; low social support at three months; and loneliness and low satisfaction with social network at six months. The baseline factors that predicted distress at six months were psychological distress, loneliness and low satisfaction with social network (Nagelkerke R2 = 0.49). Aphasia was not a predictor of distress at any time point. Yet, at three months post stroke 93% of those with aphasia experienced high distress, as opposed to 50% of those without aphasia (χ2 (1) = 8.61, P<0.01).
Conclusions: Factors contributing to distress after stroke vary across time. Loneliness and low satisfaction with one’s social network are particularly important and contribute to long-term psychological distress
Distribution of Aromatic Compounds in Coastal Bermudagrass Cell Walls Using Ultraviolet Absorption Scanning Microspectrophotometry
The distribution of aromatic constituents, including lignin , in the leaf cell walls of Coastal hermudagrass (Cynodon dacrylon (L.) Pers.) was investigated using scanning ultraviolet (UV) microspectrophotometry. Leaf blade sections and individual tissue types were scanned at three wavelengths representing the absorbance maxima (318, 287 and 250 nm) of aromatic constituents present in bermudagrass leaves. The measured absorbance data were printed in a geometric arrangement to produce an image of the distribution and amount of aromatic constituents among and within cell wall types which vary in digestibility . Differences in absorbance were observed among cell wall types, among walls of the same cell type, and at different sites in individual cell walls. Scans of the mid vein at lOX magnification showed that various tissues and cells could be distinguished on the basis of U V absorbance. The abaxial sclerenchyma and mestome sheath gave the highest absorbance followed by those of the epidermis and parenchyma bundle sheath . The lowest levels of absorbance were observed in the mesophyll, parenchyma tissue and xylem tissue. Images produced from scanning individual cell walls at lOOx magnification showed the heterogeneous nature of aromatic constituents within a cell wall. Varying the wavelength resulted in similar but not identical images, indicating that variations in the chemical structures of aromatic constituents in the cell wall can he detected using this technique
An On-Line Survey Process for Assessing Impact of an Email-Delivered Pest Advisory
IPM specialists simplified the entry, collection, editing, and distribution of pest alerts by creating a new Web site, the Virginia Ag Pest Advisory. A simple on-line survey was used to assess the usefulness of the advisory. The on-line survey was low-cost and required less effort than conventional surveys. Such a system provides feedback from users, which can be used to improve Extension programs and generates results to be used in reporting impact data
Role of material properties and mesostructure on dynamic deformation and shear instability in Al-W granular composites
Dynamic experiments with Al-W granular/porous composites revealed
qualitatively different behavior with respect to shear localization depending
on bonding between Al particles. Two-dimensional numerical modeling was used to
explore the mesomechanics of the large strain dynamic deformation in Al-W
granular/porous composites and explain the experimentally observed differences
in shear localization between composites with various mesostructures.
Specifically, the bonding between the Al particles, the porosity, the roles of
the relative particle sizes of Al and W, the arrangements of the W particles,
and the material properties of Al were investigated using numerical
calculations. It was demonstrated in simulations that the bonding between the
"soft" Al particles facilitated shear localization as seen in the experiments.
Numerical calculations and experiments revealed that the mechanism of the shear
localization in granular composites is mainly due to the local high strain flow
of "soft" Al around the "rigid" W particles causing localized damage
accumulation and subsequent growth of the meso/macro shear bands/cracks. The
"rigid" W particles were the major geometrical factor determining the
initiation and propagation of "kinked" shear bands in the matrix of "soft" Al
particles, leaving some areas free of extensive plastic deformation as observed
in experiments and numerical calculations.Comment: 10 pages, 14 figures, submitted to Journal of Applied Physic
Non-classical symmetries and the singular manifold method: A further two examples
This paper discusses two equations with the conditional Painleve property.
The usefulness of the singular manifold method as a tool for determining the
non-classical symmetries that reduce the equations to ordinary differential
equations with the Painleve property is confirmed once moreComment: 9 pages (latex), to appear in Journal of Physics
Nonlinear transport of Bose-Einstein condensates through mesoscopic waveguides
We study the coherent flow of interacting Bose-condensed atoms in mesoscopic
waveguide geometries. Analytical and numerical methods, based on the mean-field
description of the condensate, are developed to study both stationary as well
as time-dependent propagation processes. We apply these methods to the
propagation of a condensate through an atomic quantum dot in a waveguide,
discuss the nonlinear transmission spectrum and show that resonant transport is
generally suppressed due to an interaction-induced bistability phenomenon.
Finally, we establish a link between the nonlinear features of the transmission
spectrum and the self-consistent quasi-bound states of the quantum dot.Comment: 23 pages, 16 figure
First Penning-trap mass measurement in the millisecond half-life range: the exotic halo nucleus 11Li
In this letter, we report a new mass for Li using the trapping
experiment TITAN at TRIUMF's ISAC facility. This is by far the shortest-lived
nuclide, , for which a mass measurement has ever been
performed with a Penning trap. Combined with our mass measurements of
Li we derive a new two-neutron separation energy of 369.15(65) keV: a
factor of seven more precise than the best previous value. This new value is a
critical ingredient for the determination of the halo charge radius from
isotope-shift measurements. We also report results from state-of-the-art
atomic-physics calculations using the new mass and extract a new charge radius
for Li. This result is a remarkable confluence of nuclear and atomic
physics.Comment: Formatted for submission to PR
MUSTANG: 90 GHz Science with the Green Bank Telescope
MUSTANG is a 90 GHz bolometer camera built for use as a facility instrument
on the 100 m Robert C. Byrd Green Bank radio telescope (GBT). MUSTANG has an 8
by 8 focal plane array of transition edge sensor bolometers read out using
time-domain multiplexed SQUID electronics. As a continuum instrument on a large
single dish MUSTANG has a combination of high resolution (8") and good
sensitivity to extended emission which make it very competitive for a wide
range of galactic and extragalactic science. Commissioning finished in January
2008 and some of the first science data have been collected.Comment: 9 Pages, 5 figures, Presented at the SPIE conference on astronomical
instrumentation in 200
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