410 research outputs found
A monolithic collapse origin for the thin/thick disc structure of ESO 243-49
ESO 243-49 is a high-mass (circular velocity ) edge-on S0 galaxy in the Abell 2877 cluster at a distance of
. To elucidate the origin of its thick disc, we use MUSE
science verification data to study its kinematics and stellar populations. The
thick disc emits of the light at heights in excess of
(). The rotation velocities of its stars
lag by compared to those in the thin disc, which is
compatible with the asymmetric drift. The thick disc is found to be more
metal-poor than the thin disc, but both discs have old ages. We suggest an
internal origin for the thick disc stars in high-mass galaxies. We propose that
the thick disc formed either first in a turbulent phase with a high
star formation rate and that a thin disc formed shortly afterwards, or because of the dynamical heating of a thin pre-existing component. Either
way, the star formation in ESO 243-49 was quenched just a few Gyrs after the
galaxy was born and the formation of a thin and a thick disc must have occurred
before the galaxy stopped forming stars. The formation of the discs was so fast
that it could be described as a monolithic collapse where several generations
of stars formed in a rapid succession.Comment: Accepted for publication in A&A. The reduced data-cube as well as the
data necessary to build the kinematic and stellar population maps are
available at
https://etsin.avointiede.fi/dataset/urn-nbn-fi-csc-kata2016092414291163237
Adapt or preserve: Lecturers’ experiences of teaching and learning during the COVID-19 pandemic in South Africa and their self-directedness
The COVID-19 pandemic that has engulfed the whole world has given rise to a number of previously disguised challenges to higher educational institutions (HEIs). In the blink of an eye, lecturers had to facilitate learning in remote environments without any prior training. What aroused the interest in this study was the need to know how lecturers at one university dealt with the sudden shift to remote teaching during the pandemic. The way in which lecturers dealt with the shift may reveal their self-directedness. Using a qualitative open-ended questionnaire, we explored lecturers’ experiences of facilitating remote learning during the pandemic with the aim of uncovering their experiences and exploring how these experiences revealed lecturers’ self-directedness. The findings suggest that lecturers had both positive and negative experiences about facilitating online learning in their remote areas. We concluded that, even though lecturers experienced challenges in facilitating remote learning, most of them were able to introduce solutions to those challenges, indicating some element of being self-directed learners
Statins and Exercise Training Response in Heart Failure Patients: Insights From HF-ACTION.
OBJECTIVES: The aim of this study was to assess for a treatment interaction between statin use and exercise training (ET) response.
BACKGROUND: Recent data suggest that statins may attenuate ET response, but limited data exist in patients with heart failure (HF).
METHODS: HF-ACTION (Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training) was a randomized trial of 2,331 patients with chronic HF with ejection fraction ≤35% who were randomized to usual care with or without ET. We evaluated whether there was a treatment interaction between statins and ET response for the change in quality of life and aerobic capacity (peak oxygen consumption and 6-min walk distance) from baseline to 3 months. We also assessed for a treatment interaction among atorvastatin, simvastatin, and pravastatin and change in these endpoints with ET. Multiple linear regression analyses were performed for each endpoint, adjusting for baseline covariates.
RESULTS: Of 2,331 patients in the HF-ACTION trial, 1,353 (58%) were prescribed statins at baseline. Patients treated with statins were more likely to be older men with ischemic HF etiology but had similar use of renin angiotensin system blockers and beta-blockers. There was no evidence of a treatment interaction between statin use and ET on changes in quality of life or exercise capacity, nor was there evidence of differential association between statin type and ET response for these endpoints (all p values \u3e0.05).
CONCLUSIONS: In a large chronic HF cohort, there was no evidence of a treatment interaction between statin use and short-term change in aerobic capacity and quality of life with ET. These findings contrast with recent reports of an attenuation in ET response with statins in a different population, highlighting the need for future prospective studies. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437)
Monkeypox Presenting as a Hand Consult in the Emergency Department: Two Case Reports
The ongoing outbreak of the monkeypox virus (now referred to as mpox ) was deemed a public health emergency by the World Health Organization in 2022. The United States now reports the highest number of mpox cases, with 29 980 cases and 21 deaths as of January 11, 2023. The most common presenting symptom is a pruritic, vesicular rash that commonly involves the hands. While covering hand call, our division has encountered 2 cases of mpox in the emergency department for which the chief complaint was a hand lesion. Because hand surgeons will be called upon to make an initial diagnosis, the purpose of these case reports is to describe the presentation, disease course, treatment, and outcomes of these mpox patients. These patients had both uncontrolled HIV as well as other sexually transmitted disease. Symptoms included painful vesicular hand lesions with ulceration and eventual central necrosis, followed by similar lesions on the face, trunk, and genital area. Diagnosis was made using nucleic acid amplification testing through polymerase chain reaction. The patients were treated with restoration of immunity through control of HIV as well as treatment of all secondary bacterial infections. One patient died in the hospital, and the other survived without any long-term defects
Particulate matter concentrations in residences: an intervention study evaluating stand‐alone filters and air conditioners
This study, a randomized controlled trial, evaluated the effectiveness of free‐standing air filters and window air conditioners (ACs) in 126 low‐income households of children with asthma. Households were randomized into a control group, a group receiving a free‐standing HEPA filter placed in the child’s sleeping area, and a group receiving the filter and a window‐mounted AC. Indoor air quality (IAQ) was monitored for week‐long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child’s bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84 ± 27%, but dropped to 63 ± 33% in subsequent seasons. In months when households were not visited, use averaged only 34 ± 30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free‐standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Practical Implications Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m 3 and was often detected using ETS‐specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free‐standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and thus strategies are needed to encourage and maintain use of filters. The variability in filter use suggests that exposure misclassification is a potential problem in intervention studies using filters. The installation of a room AC in the bedroom, intended to limit air exchange ratios, along with an air filter, did not lower PM levels more than the filter alone.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91183/1/j.1600-0668.2011.00761.x.pd
Sex Differences in the Management and Outcomes of Heart Failure with Preserved Ejection Fraction in Patients Presenting to the Emergency Department with Acute Heart Failure
Background
Heart failure (HF) with preserved ejection fraction (HFpEF) is more common in women than in men; data characterizing sex differences in the management and outcomes of HFpEF patients presenting to the emergency department (ED) are limited.
Methods and Results
Using Acute Decompensated Heart Failure National Registry Emergency Module data linked to Medicare claims, we conducted a retrospective analysis of acute HF patients in the ED, identifying HFpEF (ejection fraction [EF] ≥40%) patients and stratifying by sex to compare baseline characteristics, ED therapies, hospital length of stay (LOS), in-hospital mortality, and post-discharge outcomes. Of 4161 HFpEF patients, 2808 (67%) were women, who were more likely to be older and hypertensive, but less likely to be diabetic or smokers (all P 140 mm Hg (62.5% vs 56.4%; P = .0001) and higher EF. There were no sex differences in ED therapies, adjusted 30- and 180-day all-cause mortality, in-hospital mortality, or 30- and 180-day readmissions. After adjustment, women had longer LOS (0.40 days, 95% confidence interval [CI] 0.10–0.70; P = .008).
Conclusions
Women with HFpEF presenting to the ED were more likely to have elevated systolic blood pressure, but overall ED management strategies were similar to those in men. We observed adjusted differences in hospital LOS, but no differences in 30- and 180-day outcomes
Differences in health care use and outcomes by the timing of in-hospital worsening heart failure
BACKGROUND:
Patients hospitalized with acute heart failure may experience worsening symptoms requiring escalation of therapy. In-hospital worsening heart failure is associated with worse in-hospital and postdischarge outcomes, but associations between the timing of worsening heart failure and outcomes are unknown.
METHODS:
Using data from a large clinical registry linked to Medicare claims, we examined characteristics, outcomes, and costs of patients hospitalized for acute heart failure. We defined in-hospital worsening heart failure by the use of inotropes or intravenous vasodilators or initiation of mechanical circulatory support, hemodialysis, or ventilation. The study groups were early worsening heart failure (n = 1,990), late worsening heart failure (n = 4,223), complicated presentation (n = 15,361), and uncomplicated hospital course (n = 41,334).
RESULTS:
Among 62,908 patients, those with late in-hospital worsening heart failure had higher in-hospital and postdischarge mortality than patients with early worsening heart failure or complicated presentation. Those with early or late worsening heart failure had more frequent all-cause and heart failure readmissions at 30 days and 1 year, with resultant higher costs, compared with patients with an uncomplicated hospital course.
CONCLUSION:
Although late worsening heart failure was associated with the highest mortality, both early and late worsening heart failures were associated with more frequent readmissions and higher health care costs compared to uncomplicated hospital course. Prevention of worsening heart failure may be an important focus in the care of hospitalized patients with acute heart failure
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