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"Neo-Liberalism?" Bullshit! Revolutionary Thought and Action Against Capital and Empire
editorialEducatio
Millennials Seeking Healthcare: Examining the Degree to Which Patients Utilize Online Resources
Introduction. According to the 2020 U.S. Census, a Silver Tsunami is looming, with more than 75.4 million persons aged 57 to 75 expected to need more costly medical care. However, a larger wave of 83.1 million Millennials nearing adulthood is approaching rapidly. Therefore, it is important to understand how this population finds their physician and what may influence this decision.
Methods. Paper-based surveys were administered to adult patients at primary care and geriatric clinics located at the University of Kansas Medical Center in Kansas City, Kansas. Questions included demographic information, utilization and influence of online reviews, and the effects negative and positive reviews have on a patient’s choice of physician. Descriptive statistics were calculated for respondent characteristics and survey responses. Chi-square and McNemar’s tests were performed to evaluate differences between age and gender groups, and to determine how influential review ratings are in choosing a physician for medical care. Statistical significance was determined at the 0.05 level.
Results. A sample of 284 patients completed the survey (44.35 ± 17.54 years old [range = 18-90], 60.6% female, 57.4% white). Of Millennials, 67.2% read online reviews before choosing a physician. Millennials were significantly more likely to read online reviews before choosing a physician (p = 0.004) and utilize online resources to search for a new physician (p < 0.001) than older patients.
Conclusions. Millennials were more likely to research online reviews before choosing a physician. Therefore, an online review presence will be beneficial to one’s practice to acquire this new wave of patients
Association of Air Pollution with Increased Incidence of Ventricular Tachyarrhythmias Recorded by Implanted Cardioverter Defibrillators
Epidemiologic studies have demonstrated a consistent link between sudden cardiac deaths and particulate air pollution. We used implanted cardioverter defibrillator (ICD) records of ventricular tachyarrhythmias to assess the role of air pollution as a trigger of these potentially life-threatening events. The study cohort consisted of 203 cardiac patients with ICD devices in the Boston metropolitan area who were followed for an average of 3.1 years between 1995 and 2002. Fine particle mass and gaseous air pollution plus temperature and relative humidity were measured on almost all days, and black carbon, sulfate, and particle number on a subset of days. Date, time, and intracardiac electrograms of ICD-detected arrhythmias were downloaded at the patients’ regular follow-up visits (about every 3 months). Ventricular tachyarrhythmias were identified by electrophysiologist review. Risk of ventricular arrhythmias associated with air pollution was estimated with logistic regression, adjusting for season, temperature, relative humidity, day of the week, patient, and a recent prior arrhythmia. We found increased risks of ventricular arrhythmias associated with 2-day mean exposure for all air pollutants considered, although these associations were not statistically significant. We found statistically significant associations between air pollution and ventricular arrhythmias for episodes within 3 days of a previous arrhythmia. The associations of ventricular tachyarrhythmias with fine particle mass, carbon monoxide, nitrogen dioxide, and black carbon suggest a link with motor vehicle pollutants. The associations with sulfate suggest a link with stationary fossil fuel combustion sources
The Galactic Inner Halo: Searching for White Dwarfs and Measuring the Fundamental Galactic Constant, Vo/Ro
We establish an extragalactic, zero-motion frame of reference within the
deepest optical image of a globular star cluster, an HST 123-orbit exposure of
M4 (GO 8679, cycle 9). The line of sight beyond M4 (l,b (deg) = 351,16)
intersects the inner halo (spheroid) of our Galaxy at a tangent-point distance
of 7.6 kpc (for Ro = 8 kpc). We isolate these spheroid stars from the cluster
based on their proper motions over the 6-year baseline between these and
previous epoch HST data (GO 5461, cycle 4). Distant background galaxies are
also found on the same sight line using image-morphology techniques. This fixed
reference frame allows us to independently determine the fundamental Galactic
constant, Vo/Ro = 25.3 +/- 2.6 km/s/kpc, thus providing a velocity of the Local
Standard of Rest, v = 202.7 +/- 24.7 km/s for Ro = 8.0 +/- 0.5 kpc. Secondly,
the galaxies allow a direct measurement of M4's absolute proper motion,
mu_total = 22.57 +/- 0.76 mas/yr, in excellent agreement with recent studies.
The clear separation of galaxies from stars in these deep data also allow us to
search for inner-halo white dwarfs. We model the conventional Galactic
contributions of white dwarfs along our line of sight and predict 7.9 (thin
disk), 6.3 (thick disk) and 2.2 (spheroid) objects to the limiting magnitude at
which we can clearly delineate stars from galaxies (V = 29). An additional 2.5
objects are expected from a 20% white dwarf dark halo consisting of 0.5 Mo
objects, 70% of which are of the DA type. After considering the kinematics and
morphology of the objects in our data set, we find the number of white dwarfs
to be consistent with the predictions for each of the conventional populations.
However, we do not find any evidence for dark halo white dwarfs.Comment: 31 pages, including 6 diagrams and 2 tables. Accepted for publication
in Ap
The Initial-Final Mass Relationship: Spectroscopy of White Dwarfs in NGC 2099 (M37)
We present new observations of very faint white dwarfs (WDs) in the rich open
star cluster NGC 2099 (M37). Following deep, wide field imaging of the cluster
using CFHT, we have now obtained spectroscopic observations of candidate WDs
using both GMOS on Gemini and LRIS on Keck. Of our 24 WD candidates (all
fainter than V = 22.4), 21 are spectroscopically confirmed to be bona fide WDs,
4-5 of which are most likely field objects. Fitting 18 of the 21 WD spectra
with model atmospheres, we find that most WDs in this cluster are quite massive
(0.7-0.9 Msun), as expected given the cluster's young age (650 Myr) and, hence,
high turnoff mass (~2.4 Msun). We determine a new initial-final mass
relationship and almost double the number of existing data points from previous
studies. The results indicate that stars with initial masses between 2.8 and
3.4 Msun lose 70-75% of their mass through stellar evolution. For the first
time, we find some evidence of a metallicity dependence on the initial-final
mass relationship.Comment: 5 pages including 3 figures and 1 table, accepted in ApJ Letters.
Minor additions to content and typos correcte
Increased Risk of Paroxysmal Atrial Fibrillation Episodes Associated with Acute Increases in Ambient Air Pollution
Objectives: We reported previously that 24-hr moving average ambient air pollution concentrations were positively associated with ventricular arrhythmias detected by implantable cardioverter defibrillators (ICDs). ICDs also detect paroxysmal atrial fibrillation episodes (PAF) that result in rapid ventricular rates. In this same cohort of ICD patients, we assessed the association between ambient air pollution and episodes of PAF. Design: We performed a case–crossover study. Participants: Patients who lived in the Boston, Massachusetts, metropolitan area and who had ICDs implanted between June 1995 and December 1999 (n = 203) were followed until July 2002. Evaluations/Measurements: We used conditional logistic regression to explore the association between community air pollution and 91 electrophysiologist-confirmed episodes of PAF among 29 subjects. Results: We found a statistically significant positive association between episodes of PAF and increased ozone concentration (22 ppb) in the hour before the arrhythmia (odds ratio = 2.08; 95% confidence interval = 1.22, 3.54; p = 0.001). The risk estimate for a longer (24-hr) moving average was smaller, thus suggesting an immediate effect. Positive but not statistically significant risks were associated with fine particles, nitrogen dioxide, and black carbon. Conclusions: Increased ambient O(3) pollution was associated with increased risk of episodes of rapid ventricular response due to PAF, thereby suggesting that community air pollution may be a precipitant of these events
HI Power Spectra and the Turbulent ISM of Dwarf Irregular Galaxies
HI spatial power spectra (PS) were determined for a sample of 24 nearby dwarf
irregular galaxies selected from the LITTLE THINGS (Local Irregulars That Trace
Luminosity Extremes - The HI Nearby Galaxy Survey) sample. The two-dimensional
(2D) power spectral indices asymptotically become a constant for each galaxy
when a significant part of the line profile is integrated. For narrow channel
maps, the PS become shallower as the channel width decreases, and this
shallowing trend continues to our single channel maps. This implies that even
the highest velocity resolution of 1.8 km/s is not smaller than the thermal
dispersion of the coolest, widespread HI component. The one-dimensional PS of
azimuthal profiles at different radii suggest that the shallower PS for
narrower channel width is mainly contributed by the inner disks, which
indicates that the inner disks have proportionally more cooler HI than the
outer disks. Galaxies with lower luminosity (M_B > -14.5 mag) and star
formation rate (SFR, log(SFR (M\odot/yr)) < -2.1) tend to have steeper PS,
which implies that the HI line-of-sight depths can be comparable with the
radial length scales in low mass galaxies. A lack of a correlation between the
inertial-range spectral indices and SFR surface density implies that either
non-stellar power sources are playing a fundamental role in driving the
interstellar medium (ISM) turbulent structure, or the nonlinear development of
turbulent structures has little to do with the driving sources.Comment: 16 pages, 9 figures, 2 tables. Accepted by Ap
The White Dwarf Cooling Sequence of the Globular Cluster Messier 4
We present the white dwarf sequence of the globular cluster M4, based on a
123 orbit Hubble Space Telescope exposure, with limiting magnitude V = 30, I =
28. The white dwarf luminosity function rises sharply for I >25.5, consistent
with the behaviour expected for a burst population. The white dwarfs of M4
extend to approximately 2.5 magnitudes fainter than the peak of the local
Galactic disk white dwarf luminosity function. This demonstrates a clear and
significant age difference between the Galactic disk and the halo globular
cluster M4. Using the same standard white dwarf models (Hansen 1999) to fit
each luminosity function yields ages of 7.3 +/- 1.5 Gyr for the disk and 12.7
+/- 0.7 Gyr for M4 (2-sigma statistical errors).Comment: 14 pages, 4 diagrams. Accepted for publication in the Astrophysical
Journal Letter
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