3,021 research outputs found
Self-regulation in multiple sclerosis: the role of illness cognitions and coping in adjustment
Multiple Sclerosis (MS) is a chronic neurological condition, which affects around 2.5 million people worldwide. At a time when there is yet no recognised cure, it is imperative that MS patients learn to cope and adjust well to living with the illness. However, research has found high rates of psychological distress associated with MS (Minden & Schiffer, 1991). This highlights the need for research to investigate the psychological factors, which make MS patients vulnerable to psychological distress. One popular social cognition model called the Self-Regulation Model (Leventhal et al., 1980) has been found to successfully predict adjustment in a range of chronic illnesses. However, previous research applying the SRM to understand adjustment to MS has been limited. The current research therefore represented the first attempt to successfully apply the full SRM to an MS population prospectively.
The present thesis is comprised of three studies and employed a mixed quantitative and qualitative research design method. Studies 1 (N=103) and 3 (N=150) were both quantitative studies, which applied an extended SRM model to clinical samples of MS patients and assessed indices of psychological distress over time. Study 2 (N=15) however was a qualitative study, designed to investigate MS patients experiences of living with the condition. By combining both quantitative and qualitative methods, the findings provided a fuller understanding of the psychological factors underlying successful adjustment to MS.
Overall the findings provided some support for the utility of the extended SRM in predicting adjustment to MS and highlighted the importance of positive mind states and acceptance for successful adjustment to the condition. The findings also had a number of clinical implications, which are also discussed
Gravitational Wave Hotspots: Ranking Potential Locations of Single-Source Gravitational Wave Emission
The steadily improving sensitivity of pulsar timing arrays (PTAs) suggests
that gravitational waves (GWs) from supermassive black hole binary (SMBHB)
systems in the nearby universe will be de- tectable sometime during the next
decade. Currently, PTAs assume an equal probability of detection from every sky
position, but as evidence grows for a non-isotropic distribution of sources, is
there a most likely sky position for a detectable single source of GWs? In this
paper, a collection of galactic catalogs is used to calculate various metrics
related to the detectability of a single GW source resolv- able above a GW
background, assuming that every galaxy has the same probability of containing a
SMBHB. Our analyses of these data reveal small probabilities that one of these
sources is currently in the PTA band, but as sensitivity is improved regions of
consistent probability density are found in predictable locations, specifically
around local galaxy clusters.Comment: 9 pages, 9 figures, accepted for submission in Ap
American Dipper, Cinclus mexicanus, Preys Upon Larval Tailed Frogs, Ascaphus truei
The American Dipper (Cinclus mexicanus) is an aquatic songbird that inhabits fast-flowing mountain streams in western North America. Although dippers are known to feed primarily on aquatic invertebrates, they will also eat juvenile fish and salmon eggs when available. In 2002, while monitoring and photographing nesting activities of the American dipper, we observed and photographed adult dippers capturing Tailed Frog (Ascaphus truei) tadpoles and feeding them to their young. This note is intended to document a rarely observed occurrence and identify interactions between two relatively uncommon species
Spectroastrometry of rotating gas disks for the detection of supermassive black holes in galactic nuclei. I. Method and simulations
This is the first in a series of papers in which we study the application of
spectroastrometry in the context of gas kinematical studies aimed at measuring
the mass of supermassive black holes. The spectroastrometrical method consists
in measuring the photocenter of light emission in different wavelength or
velocity channels. In particular we explore the potential of spectroastrometry
of gas emission lines in galaxy nuclei to constrain the kinematics of rotating
gas disks and to measure the mass of putative supermassive black holes. By
means of detailed simulations and test cases, we show that the fundamental
advantage of spectroastrometry is that it can provide information on the
gravitational potential of a galaxy on scales significantly smaller (~ 1/10)
than the limit imposed by the spatial resolution of the observations. We then
describe a simple method to infer detailed kinematical informations from
spectroastrometry in longslit spectra and to measure the mass of nuclear mass
concentrations. Such method can be applied straightforwardly to integral field
spectra, which do not have the complexities due to a partial spatial covering
of the source in the case of longslit spectra.Comment: Accepted for publication in A&
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National park research fellowships increase capacity and creativity in responding to climate change
The challenges posed by climate change in national parks and other protected areas demand creative approaches, new ideas, and experiments that are beyond the capacity of any single park or agency staff. Research fellowships provide a critical way that the National Park Service (NPS) and its partners can address the agency’s needs to address climate change adaptation challenges. At least 30 such programs support stewardship-relevant science in national parks. Some national programs and initiatives at Acadia National Park in Maine, Rocky Mountain National Park in Colorado, and Sequoia and Kings Canyon National Parks in California serve as examples of how researchers in these programs are informing restoration, relocation, vegetation and fire management, and resource protection activities; documenting change that has already occurred; providing baseline data on biodiversity; and conducting novel experiments. Successful fellowship programs have strong engagement of resource managers, emphasize communication with management and public audiences, and incorporate ongoing support and evaluation. As a result of these successes, NPS and partners are working to expand and strengthen the sustainability and effectiveness of research grants and fellowships
Absorption-line probes of the prevalence and properties of outflows in present-day star-forming galaxies
We analyze star forming galaxies drawn from SDSS DR7 to show how the
interstellar medium (ISM) Na I 5890, 5896 (Na D) absorption lines depend on
galaxy physical properties, and to look for evidence of galactic winds. We
combine the spectra of galaxies with similar geometry/physical parameters to
create composite spectra with signal-to-noise ~300. The stellar continuum is
modeled using stellar population synthesis models, and the continuum-normalized
spectrum is fit with two Na I absorption components. We find that: (1) ISM Na D
absorption lines with equivalent widths EW > 0.8A are only prevalent in disk
galaxies with specific properties -- large extinction (Av), high star formation
rates (SFR), high star formation rate per unit area (), or
high stellar mass (M*). (2) the ISM Na D absorption lines can be separated into
two components: a quiescent disk-like component at the galaxy systemic velocity
and an outflow component; (3) the disk-like component is much stronger in the
edge-on systems, and the outflow component covers a wide angle but is stronger
within 60deg of the disk rotation axis; (4) the EW and covering factor of the
disk component correlate strongly with dust attenuation, highlighting the
importance that dust shielding may play the survival of Na I. (5) The EW of the
outflow component depends primarily on and secondarily on
Av; (6) the outflow velocity varies from ~120 to 160km/s but shows little hint
of a correlation with galaxy physical properties over the modest dynamic range
that our sample probes (1.2 dex in log and 1 dex in log M*).Comment: 18 pages, 18 figures, accepted by A
Generalized Gingival Pyogenic Granuloma in a 11 Years Old Female – A Diagnostic Challenge
Aims: To include pyogenic granuloma as one of the differential diagnosis of generalized gingival enlargements.
Presentation of Case: In this article, we report a 11 years old female patient with generalized gingival enlargement, which on thorough clinical, histopathological and radiological examination concluded as a generalized gingival pyogenic granuloma.
Discussion: Pyogenic granuloma (PG), a non specific conditioned gingival enlargement is a common localized exaggerated reactive hyperplasia of connective tissue of the oral cavity or skin in response to local factors and chronic irritation. But PG presenting as a generalized gingival enlargement is very rare and uncommon. Only one case was reported on “Generalized gingival pyogenic granuloma” in 2011, showing its rarity. But in our case, in addition to generalized presentation of pyogenic granuloma, it was also associated with extensive alveolar bone loss, tooth mobility and root resorption.
Conclusion: Hence, although it is uncommon, pyogenic granuloma can also occur as a generalized gingival enlargement
Star Formation in the Field and Clusters of NGC 5253
We investigate the star formation history of both the bright star clusters
and the diffuse `field star' population in the dwarf starburst galaxy NGC 5253
using STIS longslit ultraviolet spectroscopy. Our slit covers a physical area
of 370 x 1.6 pc and includes 8 apparent clusters and several inter-cluster
regions of diffuse light which we take to be the field. The diffuse light
spectrum lacks the strong O-star wind features which are clearly visible in
spectra of the brightest clusters. This discrepancy provides compelling
evidence that the diffuse light is not reflected light from nearby clusters,
but originates in a UV-bright field star population, and it raises the issue of
whether the star formation process may be operating differently in the field
than in clusters. We compare our spectra to STARBURST99 evolutionary synthesis
models which incorporate a new low metallicity atlas of O-star spectra. We
favor a scenario which accounts for the paucity of O-stars in the field without
requiring the field to have a different IMF than the clusters: stellar clusters
form continuously and then dissolve on ~10 Myr timescales and disperse their
remaining stars into the field. We consider the probable contribution of an
O-star deficient field population to the spatially unresolved spectra of high
redshift galaxies. (Abridged)Comment: 26 pages, 10 figures, accepted for publication in Ap
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