The Impact of Insurance and a Usual Source of Care on Emergency Department Use in the United States

Background. Finding a usual source of care (USC) is difficult for certain populations. This analysis determines how insurance type and having a USC affect the settings in which patients seek care. Methods. In this cross-sectional study of the 2000–2011 Medical Expenditure Panel Surveys, we assessed the percentage of low-income persons with half or more of their ambulatory visits to the emergency department (ED). Respondents were stratified based on insurance type and presence of a USC. Results. In 2011, among Medicaid enrollees without USCs, 21.6% had half or more of their ambulatory visits to EDs compared to 8.1% for those with USCs. Among the uninsured without USCs, 24.1% went to an ED for half or more of their ambulatory visits compared to 8.8% for those with USCs in 2011. Among the privately insured without USCs, 7.8% went to an ED for half or more of their ambulatory visits compared to 5.0% for those with USCs in 2011. These differences remained in multivariate analyses. Conclusions. Those who lack USCs, particularly the uninsured and Medicaid enrollees, are more likely to rely on EDs

Electromagnetic Fields of Slowly Rotating Magnetized Gravastars

We study the dipolar magnetic field configuration and present solutions of Maxwell equations in the internal background spacetime of a a slowly rotating gravastar. The shell of gravastar where magnetic field penetrated is modeled as sphere consisting of perfect highly magnetized fluid with infinite conductivity. Dipolar magnetic field of the gravastar is produced by a circular current loop symmetrically placed at radius $a$ at the equatorial plane.Comment: 5 pages, 2 figures, accepted for publication to Mod. Phys. Lett.

CaII absorption in the circumstellar disk of Beta Pictoris and other A-type stars

Presented here are the results of observations made at the Mount John Observatory (MJUO) during the spectroscopic campaigns to observe beta Pictoris in 1992, 1993, 1994 and observations conducted in 1995 to characterise the behaviour of the Ca II H and K lines and to test the Falling Evaporating Bodies scenario. Using the method of division by a reference spectrum both narrow and broad variable absorption features in both the redshifted and blue shifted sides of the Ca II H and K lines are clearly detected. The large data set obtained allows the determination of the evolution in terms of velocity, equivalent width, FWHM and timescales of variability of the variable absorption features. These are then compared with the results on Lagrange-Henri et al. (1996) in their paper on the 1992 observing campaign. Lagrange-Henri et al. find that there are 2 velocity regimes and this is confirmed in the MJUO data. The higher the redshift, the smaller the variability timescales and the smaller the absorbing cloud. In contrast the low velocity features tend to be longer lived and to have the deeper absorptions. The correlation between the FWHM and velocity of the features found by Lagrange-Henri et al. is confirmed, but with the larger set of data the correlation is found to be somewhat weaker. Significant activity was seen in each set of observations with long lived absorption features at low velocity almost always being present and it has been found that ¼ of all features observed are most likely due to more than one FEB. The effect of stellar rotation is suggested in the data of some of the strong and more variable absorption features. However conclusive evidence of the changes in equivalent width are not forthcoming. Large numbers of high velocity features are also observed and are seen to vary in timescales no longer than the crossing time for an orbiting body to pass across the stellar disk. This lends further support to the FEB scenario as an explanation for the variable absorption features. The measurement of the filling factors of the clouds of ions indicate that these clouds do in indeed cover large fractions of the stellar disk and some of the lines even exhibit pK/pH less than 1, as predicted. The FEB scenario appears to explain many of the characteristics of the variable absorption features very well, simulations can reproduce many of the absorptions however there are some cases where the FEB scenario fails to adequately explain the observations. The ability for some of the long-lived features to last as long as they are observed would require either large numbers of bodies on similar orbits crossing the line of sight for many weeks, or that there is some other explanation for the origin of the absorptions

Facial conformation characteristics in Persian and Exotic Shorthair cats

ObjectivesThe primary objectives of the study were to examine the diversity in facial conformation characteristics within a group of Persian (PER) and Exotic Shorthair (EXO) show cats, and to contrast the results to findings within a group of non-purebred domestic shorthair (DSH) and domestic longhair (DLH) cats. The secondary objectives were to determine the PER/EXO show cat owners' perceptions of the breathing status of their cats, and to evaluate if remarks from the cat show judges concerning the cats' head and facial conformation were exclusively related to the aesthetic features of the cats.MethodsSixty-four PER and 12 EXO show cats were prospectively examined at five international cat shows, and 20 DSH/DLH cats were examined at an animal hospital. Facial conformation characteristics were evaluated by examining photos of the cats. Owners of the PER/EXO show cats answered a questionnaire concerning their cats' health status, and they were encouraged to send in the judges' score sheets from the cat shows.ResultsThe PER/EXO show cats had higher diversity in facial conformation characteristics than the DSH/DLH cats, and high incidences of hypoplasia of the nose leather (95%), the nose leather top positioned above the level of the lower eyelid (93%), moderate-to-severe stenotic nares (86%), epiphora (83%) and entropion (32%). Owners of 6/76 PER/EXO show cats stated that their cat had increased respiratory sounds and/or trouble breathing at least once a week. The cat show judges' written comments were exclusively related to aesthetic features of the cats' head and facial conformation details.Conclusions and relevanceHypoplasia of the nose leather, high position of the nose leather top, stenotic nares, epiphora and entropion were common findings in the PER/EXO show cats but not in the DSH/DLH cats. Few of the cat owners perceived that their cat had problems related to the airways

Early Quadriceps Strength Loss After Total Knee Arthroplasty : The Contributions of Muscle Atrophy and Failure of Voluntary Muscle Activation

While total knee arthroplasty reduces pain and provides a functional range of motion of the knee, quadriceps weakness and reduced functional capacity typically are still present one year after surgery. The purpose of the present investigation was to determine the role of failure of voluntary muscle activation and muscle atrophy in theearly loss of quadriceps strength after surgery

Implications of nonlinearity for spherically symmetric accretion

We subject the steady solutions of a spherically symmetric accretion flow to a time-dependent radial perturbation. The equation of the perturbation includes nonlinearity up to any arbitrary order, and bears a form that is very similar to the metric equation of an analogue acoustic black hole. Casting the perturbation as a standing wave on subsonic solutions, and maintaining nonlinearity in it up to the second order, we get the time-dependence of the perturbation in the form of a Li\'enard system. A dynamical systems analysis of the Li\'enard system reveals a saddle point in real time, with the implication that instabilities will develop in the accreting system when the perturbation is extended into the nonlinear regime. The instability of initial subsonic states also adversely affects the temporal evolution of the flow towards a final and stable transonic state.Comment: 14 pages, ReVTeX. Substantially revised with respect to the previous version. Three figures and a new section (Sec. VI) adde

Perturbations on steady spherical accretion in Schwarzschild geometry

The stationary background flow in the spherically symmetric infall of a compressible fluid, coupled to the space-time defined by the static Schwarzschild metric, has been subjected to linearized perturbations. The perturbative procedure is based on the continuity condition and it shows that the coupling of the flow with the geometry of space-time brings about greater stability for the flow, to the extent that the amplitude of the perturbation, treated as a standing wave, decays in time, as opposed to the amplitude remaining constant in the Newtonian limit. In qualitative terms this situation simulates the effect of a dissipative mechanism in the classical Bondi accretion flow, defined in the Newtonian construct of space and time. As a result of this approach it becomes impossible to define an acoustic metric for a conserved spherically symmetric flow, described within the framework of Schwarzschild geometry. In keeping with this view, the perturbation, considered separately as a high-frequency travelling wave, also has its amplitude reduced.Comment: 8 pages, no figur

New homogeneous iron abundances of double-mode Cepheids from high-resolution echelle spectroscopy

Aims: We define the relationship between the double-mode pulsation of Cepheids and metallicity in a more accurate way, determine the empirical metallicities of double-mode Cepheids from homogeneous, high-resolution spectroscopic data, and study of the period-ratio -- metallicity dependence. Methods: The high S/N echelle spectra obtained with the FEROS spectrograph were analyzed using a self-developed IRAF script, and the iron abundances were determined by comparing with synthetic spectra assuming LTE. Results: Accurate [Fe/H] values of 17 galactic beat Cepheids were determined. All these stars have solar or slightly subsolar metallicity. Their period ratio P1/P0 shows strong correlation with their derived [Fe/H] values. The corresponding period ratio -- metallicity relation has been evaluated.Comment: 10 pages, 7 figures, accepted in A&