295 research outputs found
The Benefits of Alternative and Augmentative Communication: A Quality of Life Issue
This article summarizes the need for alternate forms of communication for those who are unable to use verbal speech. The importance of allied health professionals in understanding alternative communication is critical in patient care. The authors describe the various forms of augmentative and alternate communication devices that can be used to help a non-verbal individual communicate their wants, needs, and thoughts. Financial and social consequences for using these devices is discussed
Evolution since z = 0.5 of the Morphology-Density relation for Clusters of Galaxies
Using traditional morphological classifications of galaxies in 10
intermediate-redshift (z~0.5) clusters observed with WFPC-2 on the Hubble Space
Telescope, we derive relations between morphology and local galaxy density
similar to that found by Dressler for low-redshift clusters. Taken
collectively, the `morphology-density' relationship, M-D, for these more
distant, presumably younger clusters is qualitatively similar to that found for
the local sample, but a detailed comparison shows two substantial differences:
(1) For the clusters in our sample, the M-D relation is strong in centrally
concentrated ``regular'' clusters, those with a strong correlation of radius
and surface density, but nearly absent for clusters that are less concentrated
and irregular, in contrast to the situation for low redshift clusters where a
strong relation has been found for both. (2) In every cluster the fraction of
elliptical galaxies is as large or larger than in low-redshift clusters, but
the S0 fraction is 2-3 times smaller, with a proportional increase of the
spiral fraction. Straightforward, though probably not unique, interpretations
of these observations are (1) morphological segregation proceeds
hierarchically, affecting richer, denser groups of galaxies earlier, and (2)
the formation of elliptical galaxies predates the formation of rich clusters,
and occurs instead in the loose-group phase or even earlier, but S0's are
generated in large numbers only after cluster virialization.Comment: 35 pages, 19 figures, uses psfig. Accepted for publication in Ap
HST Observations of Giant Arcs: High Resolution Imaging Of Distant Field Galaxies.
We present HST imaging of eight spectroscopically-confirmed giant arcs, pairs
and arclets. These objects have all been extensively studied from the ground
and we demonstrate the unique advantages of HST imaging in the study of such
features by a critical comparison of our data with the previous observations.
In particular we present new estimates of the core radii of two clusters
(Cl0024+16, A370) determined from lensed features which are identifiable in our
HST images. Although our HST observations include both pre- and
post-refurbishment images, the depth of the exposures guarantees that the
majority of the arcs are detected with diffraction-limited resolution. A number
of the objects in our sample are multiply-imaged and we illustrate the ease of
identification of such features when working at high resolution. We discuss the
morphological and scale information on these distant field galaxies in the
light of HST studies of lower redshift samples. We conclude that the dominant
population of star-forming galaxies at z=1 is a factor of 1.5-2 times smaller
than the similar group in the local field. This implies either a considerable
evolution in the sizes of star-forming galaxies within the last 10 Gyrs
or a shift in the relative space densities of massive and dwarf star-forming
systems over the same timescale.Comment: 9 pages (no figures), uuencoded, compressed Postscript. Postscript
text, tables and figures (803 Kb) available via anonymous ftp in at
ftp://ociw.edu//pub/irs/pub/hstarcs.tar.
Fatalistic Beliefs and Completion of the HPV Vaccination Series Among a Sample of Young Appalachian Kentucky Women
PURPOSE: Uptake and completion of the 3-dose human papillomavirus (HPV) vaccine is important for the primary prevention of cervical cancer. However, HPV vaccination rates among adolescent females and young women remain low in certain geographic areas of the United States, including Appalachia. Although greater fatalistic beliefs have been previously associated with lower rates of preventive cancer behaviors among adults, little research exists on the impact of fatalism on HPV vaccination behaviors, especially among younger individuals. Therefore, the purpose of this study was to examine the association between fatalistic beliefs and completion of the full HPV vaccine series among young women, ages 18-26, in Appalachian Kentucky.
RESULTS: Data from this study were from a baseline survey completed by 344 women randomized into a communication intervention trial focused on increasing adherence to the 3-dose HPV vaccine series. Principal components analysis was used to construct 2 fatalism-related subscales from 8 survey questions.
FINDINGS: In a controlled analysis, 1 subscale-- lack of control over cancer --was significantly associated with not completing the full HPV vaccine series. In a rural area that experiences higher rates of cervical cancer, poverty, limited access to health care, and negative cancer-related attitudes and experiences, fatalism may be common, even among young people.
CONCLUSION: Future educational and interventional research addressing fatalistic beliefs in a culturally sensitive manner may be warranted to improve HPV vaccination behaviors and impact cancer disparities among Appalachian women
The Black Hole Mass and Extreme Orbital Structure in NGC1399
The largest galaxies, and in particular central galaxies in clusters, offer
unique insight into understanding the mechanism for the growth of nuclear black
holes. We present Hubble Space Telescope kinematics for NGC1399, the central
galaxy in Fornax. We find the best-fit model contains a black hole of 5.1 +-0.7
x 10^8 Msun (at a distance of 21.1 Mpc), a factor of over 2 below the
correlation of black hole mass and velocity dispersion. We also find a dramatic
signature for central tangential anisotropy. The velocity profiles on adjacent
sides 0.5" away from the nucleus show strong bimodality, and the central
spectrum shows a large drop in the dispersion. Both of these observations point
to an orbital distribution that is tangentially biased. The best-fit orbital
model suggests a ratio of the tangential to radial internal velocity
dispersions of three. This ratio is the largest seen in any galaxy to date and
will provide an important measure for the mode by which the central black hole
has grown.Comment: 9 pages, accepted for publication in the Astrophysical Journa
A Quintet Of Black Hole Mass Determinations
We report five new measurements of central black hole masses based on Space Telescope Imaging Spectrograph and Wide Field Planetary Camera 2 observations with the Hubble Space Telescope (HST) and on axisymmetric, three-integral, Schwarzschild orbit-library kinematic models. We selected a sample of galaxies within a narrow range in velocity dispersion that cover a range of galaxy parameters (including Hubble type and core/power-law surface density profile) where we expected to be able to resolve the galaxy's sphere of influence based on the predicted value of the black hole mass from the M-sigma relation. We find masses for the following galaxies: NGC3585, M(BH) = 3.4(-0.6)(+1.5) x 10(8) M(circle dot;) NGC 3607, M(BH) = 1.2(-0.4)(+0.4) x 10(8) M(circle dot); NGC 4026, M(BH) = 2.1(-0.4)(+0.7) x 10(8) M(circle dot); and NGC 5576, M(BH) = 1.8(-0.4)(+0.3) x 10(8) M(circle dot), all significantly excluding M(BH) = 0. For NGC 3945, M(BH) = 9(-21)(+17) x 10(6) M(circle dot), which is significantly below predictions from M-sigma and M-L relations and consistent with MBH = 0, though the presence of a double bar in this galaxy may present problems for our axisymmetric code.NASA/HST GO-5999, GO-6587, GO-6633, GO-7468, GO-9107NASA NAS 5-26555Astronom
A Catalog of Morphological Types in 10 Distant Rich Clusters of Galaxies
We present catalogs of objects detected in deep images of 11 fields in 10
distant clusters obtained using WFPC-2 on board the Hubble Space Telescope. The
clusters span the redshift range z=0.37-0.56 and are the subject of a detailed
ground- and space-based study to investigate the evolution of galaxies as a
function of environment and epoch. The data presented here include positions,
photometry and basic morphological information on ~9000 objects in the fields
of the 10 clusters. For a brighter subset of 1857 objects in these areas we
provide more detailed morphological information.Comment: 24 pages, Latex (uses side.sty - included), 7 figures, accepted for
publication in ApJS. Full tables, plates and images are to be distributed on
AAS CD-ROM and are not included here. Catalogs now available at
http://www.ociw.edu/~ir
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