337 research outputs found
Arthroscopic transosseous rotator cuff repair: A prospective study on cost savings, surgical time, and outcomes
Objectives: Health expenditures in the United States are outpacing national income, and affordability has become a major policy issue. Over 500,000 rotator cuff repairs (RCR) are performed annually in the United States making RCR a potential source of cost savings. Arthroscopic trans-osseous equivalent (TOE) repair using a double row of anchors has shown superior biomechanical strength compared to other techniques, but at a higher cost. The arthroscopic transosseous (TO) repair is a novel technique allowing arthroscopic rotator cuff repair to be performed without suture anchors. Arthroscopic TO repair may be a means to provide similarly excellent patient outcomes while lowering the cost of care. The primary purpose is to compare the price differential and time of surgery for an arthroscopic rotator cuff repair using anchorless TO repair verses an anchor trans-osseous equivalent (TOE) repair. A secondary purpose of the study was to evaluate outcomes at 6 months postoperatively. Methods: A prospective, case-controlled study evaluating arthroscopic rotator cuff repair using two techniques was performed. The study group consisting of 21 patients undergoing TO repair was compared to a control group consisting of 22 patients undergoing TOE repair. The groups were controlled for size of tear, biceps treatment, acromioplasty, distal clavicle excision, and labral pathology. The primary outcome measures were surgical time as well as total cost of implants and equipment for each surgery, determined by an independent third party, Atlanticare Hospital. Secondary outcomes were changes in the SST, VAS, and SANE scores. Results: Mean total surgical implant/equipment cost per procedure for TOE repair was 1204.97 (SD 330.69; p\u3c0.0001). Mean cut to close time for TOE repair was 85 minutes (95% CI is 77-90) verses 74 (95% CI = 71-98) for TO repair. A log rank test revealed no difference in time (p =0.95). A linear regression model was developed to evaluate the change in SST, VAS, and SANE scores from pre-op to 6 months follow-up. Our study was underpowered but no difference in outcome was observed. Conclusion: Arthroscopic TO rotator cuff repair is a cost savings and time neutral technique compared to TOE repair. A mean of $1100 can be saved in surgical cost per case. In a country that performs over 500,000 RCRs annually, utilizing a TO repair technique can provide substantial cost savings to the healthcare system. © The Author(s) 2015
The Spitzer mid-infrared AGN survey. II-the demographics and cosmic evolution of the AGN population
We present luminosity functions derived from a spectroscopic survey of AGN
selected from Spitzer Space Telescope imaging surveys. Selection in the
mid-infrared is significantly less affected by dust obscuration. We can thus
compare the luminosity functions of the obscured and unobscured AGN in a more
reliable fashion than by using optical or X-ray data alone. We find that the
AGN luminosity function can be well described by a broken power-law model in
which the break luminosity decreases with redshift. At high redshifts
(), we find significantly more AGN at a given bolometric luminosity than
found by either optical quasar surveys or hard X-ray surveys. The fraction of
obscured AGN decreases rapidly with increasing AGN luminosity, but, at least at
high redshifts, appears to remain at \% even at bolometric
luminosities . The data support a picture in which the
obscured and unobscured populations evolve differently, with some evidence that
high luminosity obscured quasars peak in space density at a higher redshift
than their unobscured counterparts. The amount of accretion energy in the
Universe estimated from this work suggests that AGN contribute about 12\% to
the total radiation intensity of the Universe, and a high radiative accretion
efficiency is required to match current
estimates of the local mass density in black holes.Comment: 14 pages, accepted by Ap
Introduction by Guest Editors
This book grew out of conversations among the three guest editors, Mark Cammack, Michael Feener, and Clark Lombardi, in the summer of 2008 about the general lack of attention among scholars of Southeast Asian Islam on important questions about the foundations of the region’s Islamic legal structures. First, despite its evident importance, there has been little research on the process by which legislators and judges decide which interpretation of Islamic law will be formally applied by the state apparatus. Another important question that has been largely ignored by scholars concerns the qualifications of Islamic legal professionals. The three Southeast Asian states treated in this volume—Indonesia, Malaysia and Singapore—have separate systems of Islamic courts. Although the educational background of those who staff these courts will clearly inform the way they understand, interpret, and apply the law, to date little research has been done on the educational processes by which judges who serve on Islamic courts are trained to think about Islamic law. Studies on the means by which judges are appointed and regulated have also been lacking—even though the decision to favor one type of candidate surely affects the interpretation and application of Islamic law in the courts. Finally, lawyers who practice before Islamic courts play a crucial role in framing and presenting the issues for decision and in mediating between the courts that apply Islamic law and the public who have recourse to the state’s official Islamic legal institutions, but research on the professional training and governance of these lawyers is almost entirely lackin
Imaging and spectroscopy of galaxies associated with two z~0.7 damped Lyman-alpha absorption systems
We have identified galaxies near two quasars which are at the redshift of
damped Lyman-alpha (DLA) systems in the UV spectra of the quasars. Both
galaxies are actively forming stars. One galaxy has a luminosity close to the
break in the local galaxy luminosity function, L*, the other is significantly
fainter than L* and appears to be interacting with a nearby companion. Despite
the strong selection effects favoring spectroscopic identification of the most
luminous DLA galaxies, many of the spectroscopically-identified DLA galaxies in
the literature are sub-L*, suggesting that the majority of the DLA population
is probably sub-L*, in contrast to MgII absorbers at similar redshifts whose
mean luminosity is close to L*.Comment: 9 pages, to appear in AJ, November 2003 issu
The Spitzer Warm Mission Science Prospects
After exhaustion of its cryogen, the Spitzer Space telescope will still have a fully functioning two-channel mid-IR camera that will have sensitivities better than any other ground or space-based telescopes until the launch of JWST. This document provides a description of the expected capabilities of Spitzer during its warm mission phase, and provides brief descriptions of several possible very large science programs that could be conducted. This information is intended to serve as input to a wide ranging discussion of the warm mission science, leading up to the Warm Mission Workshop in June 2007
On the shear estimation bias induced by the spatial variation of colour across galaxy profiles
The spatial variation of the colour of a galaxy may introduce a bias in the
measurement of its shape if the PSF profile depends on wavelength. We study how
this bias depends on the properties of the PSF and the galaxies themselves. The
bias depends on the scales used to estimate the shape, which may be used to
optimise methods to reduce the bias. Here we develop a general approach to
quantify the bias. Although applicable to any weak lensing survey, we focus on
the implications for the ESA Euclid mission.
Based on our study of synthetic galaxies we find that the bias is a few times
10^-3 for a typical galaxy observed by Euclid. Consequently, it cannot be
neglected and needs to be accounted for. We demonstrate how one can do so using
spatially resolved observations of galaxies in two filters. We show that HST
observations in the F606W and F814W filters allow us to model and reduce the
bias by an order of magnitude, sufficient to meet Euclid's scientific
requirements. The precision of the correction is ultimately determined by the
number of galaxies for which spatially-resolved observations in at least two
filters are available. We use results from the Millennium Simulation to
demonstrate that archival HST data will be sufficient for the tomographic
cosmic shear analysis with the Euclid dataset.Comment: MNRAS submitted, 18 pages, 13 Figure
Phylogeny of Celastraceae (spindle-tree family) subfamilies Hippocrateoideae and Salacioideae inferred from chloroplast and nuclear genes
The phylogeny of Celastraceae (the spindle-tree family) subfamilies Hippocrateoideae and Salacioideae, which include about 360 species of shrubs, trees, and vines in 25 genera, was inferred using plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) genes. Together, subfamilies Hippocrateoideae and Salacioideae contain all members of the former Hippocrateaceae, which are now recognized as a derived group within Celastraceae sensu stricto. Based on our results, Brassiantha, a monotypic genus endemic to New Guinea, is more closely related to the clade of Dicarpellum (New Caledonia) and Hypsophila (Queensland, Australia) than it is to the former Hippocrateaceae, in contrast to previous studies. This well supported resolution indicates that having a nectary disk positioned outside the stamens has been convergently derived in these two separate lineages. The clade of Kokoona and Lophopetalum was resolved as sister to the clade of Hippocrateoideae, Sarawakodendron, and Salacioideae. This resolution of Kokoona and Lophopetalum supports previous assertions that they are a "transitional link" between Celastraceae sensu stricto and the former Hippocrateaceae. Sarawakodendron, a monotypic genus endemic to Borneo, was resolved as sister to the clade of Salacioideae, which supports earlier assertions that Sarawakodendron is "transitional" between Kokoona, Lophopetalum, and Salacioideae. Based on our inferred phylogeny, arils as mucilaginous pulp are derived within Salacioideae and winged arils may be primitive within the former Hippocrateaceae as a whole. Finally, the former Hippocrateaceae had an Old World, rather than a New World, origin.College Honors
Imaging and Spectroscopy of Galaxies Associated with Two z ~ 0.7 Damped Lyα Absorption Systems
We have identified galaxies near two quasars that are at the redshift of damped Lyα (DLA) systems in the UV spectra of the quasars. Both galaxies are actively forming stars. One galaxy has a luminosity close to the break in the local galaxy luminosity function, L*; the other is significantly fainter than L* and appears to be interacting with a nearby companion. Despite the strong selection effects favoring spectroscopic identification of the most luminous DLA galaxies, many of the spectroscopically identified DLA galaxies in the literature are sub-L*, suggesting that the majority of the DLA population is probably sub-L*, in contrast to Mg II absorbers at similar redshifts, whose mean luminosity is close to L*
An Infrared Comparison of Type-1 and Type-2 Quasars
We model the optical to far-infrared SEDs of a sample of six type-1 and six
type-2 quasars selected in the mid-infrared. The objects in our sample are
matched in mid-IR luminosity and selected based on their Spitzer IRAC colors.
We obtained new targeted Spitzer IRS and MIPS observations and used archival
photometry to examine the optical to far-IR SEDs. We investigate whether the
observed differences between samples are consistent with orientation-based
unification schemes. The type-1 objects show significant emission at 3 micron.
They do not show strong PAH emission and have less far-IR emission on average
when compared to the type-2 objects. The SEDs of the type-2 objects show a wide
assortment of silicate features, ranging from weak emission to deep silicate
absorption. Some also show strong PAH features. In comparison, silicate is only
seen in emission in the type-1 objects. This is consistent with some of the
type-2s being reddened by a foreground screen of cooler dust, perhaps in the
host galaxy itself. We investigate the AGN contribution to the far-IR emission
and find it to be significant. We also estimate the star formation rate for
each of the objects by integrating the modeled far-IR flux and compare this
with the SFR found from PAH emission. We find the type-2 quasars have a higher
average SFR than the type-1 quasars based on both methods, though this could be
due to differences in bolometric luminosities of the objects. While we find
pronounced differences between the two types of objects, none of them are
inconsistent with orientation-based unification schemes.Comment: Accepted for publication in Ap
Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
We present an analysis of the mid-infrared (MIR) and optical properties of type 1 (broad-line) quasars detected by the Spitzer Space Telescope. The MIR color-redshift relation is characterized to z ~ 3, with predictions to z = 7. We demonstrate how combining MIR and optical colors can yield even more efficient selection of active galactic nuclei (AGNs) than MIR or optical colors alone. Composite spectral energy distributions (SEDs) are constructed for 259 quasars with both Sloan Digital Sky Survey and Spitzer photometry, supplemented by near-IR, GALEX, VLA, and ROSAT data, where available. We discuss how the spectral diversity of quasars influences the determination of bolometric luminosities and accretion rates; assuming the mean SED can lead to errors as large as 50% for individual quasars when inferring a bolometric luminosity from an optical luminosity. Finally, we show that careful consideration of the shape of the mean quasar SED and its redshift dependence leads to a lower estimate of the fraction of reddened/obscured AGNs missed by optical surveys as compared to estimates derived from a single mean MIR to optical flux ratio
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