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Assessment of asthma control and asthma exacerbations in the epidemiology and natural history of asthma: outcomes and treatment regimens (TENOR) observational cohort
Patients with severe or difficult-to-treat asthma account for substantial asthma morbidity, mortality, and healthcare burden despite comprising only a small proportion of the total asthma population. TENOR, a multicenter, observational, prospective cohort study was initiated in 2001. It enrolled 4,756 adults, adolescents and children with severe or difficult-to-treat asthma who were followed semi-annually and annually for three years, enabling insight to be gained into this understudied population. A broad range of demographic, clinical, and patient self-reported assessments were completed during the follow-up period. Here, we present key findings from the TENOR registry in relation to asthma control and exacerbations, including the identification of specific subgroups found to be at particularly high-risk. Identification of the factors and subgroups associated with poor asthma control and increased risk of exacerbations can help physicians design individual asthma management, and improve asthma-related health outcomes for these patients
Type Ia Supernova Rate Measurements To Redshift 2.5 From CANDELS: Searching For Prompt Explosions In The Early Universe
dThe Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope (HST) that surveyed a total area of -0.25 deg2 with -900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z 2.5. We classify -24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z =- 2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only -3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation ( 40 Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z > 1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20% of all SN Ia explosions-though further analysis and larger samples will be needed to examine that suggestion. Key words: infrared: general - supernovae:Astronom
Are we missing the target? Are we aiming too low? What are the aerobic exercise prescriptions and their effects on markers of cardiovascular health and systemic inflammation in patients with knee osteoarthritis? A systematic review and meta-analysis
© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ. Objectives We systemically reviewed published studies that evaluated aerobic exercise interventions in patients with knee osteoarthritis (OA) to: (1) report the frequency, intensity, type and time (FITT) of exercise prescriptions and (2) quantify the changes in markers of cardiovascular health and systemic inflammation. Data sources PubMed, CINAHL, Scopus; inception to January 2019. Eligibility criteria Randomised clinical trials (RCT), cohort studies, case series. Design We summarised exercise prescriptions for all studies and calculated effect sizes with 95% CIs for between-group (RCTs that compared exercise and control groups) and within-group (pre-post exercise) differences in aerobic capacity (VO 2), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and inflammatory markers (interleukin-6 (IL-6), tumour necrosis factor-alpha). We pooled results where possible using random effects models. Results Interventions from 49 studies were summarised; 8% (4/49) met all FITT guidelines; 16% (8/49) met all or most FITT guidelines. Fourteen studies (10 RCTs) reported at least one marker of cardiovascular health or systemic inflammation. Mean differences (95% CI) indicated a small to moderate increase in VO 2 (0.84 mL/min/kg; 95% CI 0.37 to 1.31), decrease in HR (-3.56 beats per minute; 95% CI -5.60 to -1.52) and DBP (-4.10 mm Hg; 95% CI -4.82 to -3.38) and no change in SBP (-0.36 mm Hg; 95% CI -3.88 to 3.16) and IL-6 (0.37 pg/mL; 95% CI -0.11 to 0.85). Within-group differences were also small to moderate. Conclusions In studies of aerobic exercise in patients with knee OA, very few interventions met guideline-recommended dose; there were small to moderate changes in markers of cardiovascular health and no decrease in markers of systemic inflammation. These findings question whether aerobic exercise is being used to its full potential in patients with knee OA. PROSPERO registration number CRD42018087859
Tracing chemical evolution over the extent of the Milky Way's Disk with APOGEE Red Clump Stars
We employ the first two years of data from the near-infrared, high-resolution
SDSS-III/APOGEE spectroscopic survey to investigate the distribution of
metallicity and alpha-element abundances of stars over a large part of the
Milky Way disk. Using a sample of ~10,000 kinematically-unbiased red-clump
stars with ~5% distance accuracy as tracers, the [alpha/Fe] vs. [Fe/H]
distribution of this sample exhibits a bimodality in [alpha/Fe] at intermediate
metallicities, -0.9<[Fe/H]<-0.2, but at higher metallicities ([Fe/H]=+0.2) the
two sequences smoothly merge. We investigate the effects of the APOGEE
selection function and volume filling fraction and find that these have little
qualitative impact on the alpha-element abundance patterns. The described
abundance pattern is found throughout the range 5<R<11 kpc and 0<|Z|<2 kpc
across the Galaxy. The [alpha/Fe] trend of the high-alpha sequence is
surprisingly constant throughout the Galaxy, with little variation from region
to region (~10%). Using simple galactic chemical evolution models we derive an
average star formation efficiency (SFE) in the high-alpha sequence of ~4.5E-10
1/yr, which is quite close to the nearly-constant value found in
molecular-gas-dominated regions of nearby spirals. This result suggests that
the early evolution of the Milky Way disk was characterized by stars that
shared a similar star formation history and were formed in a well-mixed,
turbulent, and molecular-dominated ISM with a gas consumption timescale (1/SFE)
of ~2 Gyr. Finally, while the two alpha-element sequences in the inner Galaxy
can be explained by a single chemical evolutionary track this cannot hold in
the outer Galaxy, requiring instead a mix of two or more populations with
distinct enrichment histories.Comment: 18 pages, 17 figures. Accepted for publication in Ap
model of superconducting UPt
The phase diagram of superconducting UPt is explained in a
Ginzburg-Landau theory starting from the hypothesis that the order parameter is
a pseudo-spin singlet which transforms according to the representation
of the point group. We show how to compute the positions of the phase
boundaries both when the applied field is in the basal plane and when it is
along the c-axis. The experimental phase diagrams as determined by longitudinal
sound velocity data can be fit using a single set of parameters. In particular
the crossing of the upper critical field curves for the two field directions
and the apparent isotropy of the phase diagram are reproduced. The former is a
result of the magnetic properties of UPt and their contribution to the free
energy in the superconducting state. The latter is a consequence of an
approximate particle-hole symmetry. Finally we extend the theory to finite
pressure and show that, in contrast to other models, the model
explains the observed pressure dependence of the phase boundaries.Comment: RevTex, 29 pages, 18 PostScript figures in a uuencoded, gzipped tar
file. PostScript version of paper, tar file of PostScript figures and
individual PostScript figures are also available via anonymous ftp at
ftp://nym.physics.wisc.edu/anonymou/papers/upt3
Encountering Berlant part one: Concepts otherwise
In Part 1 of ‘Encountering Berlant’, we encounter the promise and provocation of Lauren Berlant's work. In 1000-word contributions, geographers and others stay with what Berlant's thought offers contemporary human geography. They amplify an encounter with their work, demonstrating how a concept, idea, or style disrupts something, opens up a new possibility, or simply invites thinking otherwise. The encounters range across the incredible body of work Berlant left us with, from the ‘national sentimentality’ trilogy through to recent work on negativity. Varying in form and tone, the encounters exemplify and enact the inexhaustible plenitude of Berlant's thought: fantasy, the case, love, impasse, feel tanks, slow death, ellipses, gesture, attrition, intimate public, ambivalence, style. Part 2 of ‘Encountering Berlant’ focuses on Berlant's most influential concept: ‘cruel optimism’. Across these heterogeneous encounters, Berlant's enduring concern with the tensions and possibilities of relationality and how to enact better forms of common life shine through. These enduring concerns and Berlant's commitment to the incoherence and overdetermination of phenomena are summarised in the Introduction, which also explores how Berlant's work has been engaged with in geography. The result is a repository of what an encounter with Berlant's thought makes possible.
Short Abstract
Part 1 of ‘Encountering Berlant’ explores the promise and provocation of Lauren Berlant's work. Contributors amplify an encounter with Berlant's concepts, tones, and styles, drawing out their implications for understanding relationality and how to invent and live better ways of being in common. The result is a repository of what Berlant's thinking offers geographers
Encountering Berlant part 1: Concepts otherwise
In Part 1 of ‘Encountering Berlant’, we encounter the promise and provocation of Lauren Berlant's work. In 1000-word contributions, geographers and others stay with what Berlant's thought offers contemporary human geography. They amplify an encounter with their work, demonstrating how a concept, idea, or style disrupts something, opens up a new possibility, or simply invites thinking otherwise. The encounters range across the incredible body of work Berlant left us with, from the ‘national sentimentality’ trilogy through to recent work on negativity. Varying in form and tone, the encounters exemplify and enact the inexhaustible plenitude of Berlant's thought: fantasy, the case, love, impasse, feel tanks, slow death, ellipses, gesture, attrition, intimate public, ambivalence, style. Part 2 of ‘Encountering Berlant’ focuses on Berlant's most influential concept: ‘cruel optimism’. Across these heterogeneous encounters, Berlant's enduring concern with the tensions and possibilities of relationality and how to enact better forms of common life shine through. These enduring concerns and Berlant's commitment to the incoherence and overdetermination of phenomena are summarised in the Introduction, which also explores how Berlant's work has been engaged with in geography. The result is a repository of what an encounter with Berlant's thought makes possible
The GALAH survey: velocity fluctuations in the Milky Way using red clump giants
If the Galaxy is axisymmetric and in dynamical equilibrium, we expect negligible fluctuations in the residual line-of-sight velocity field. However, non-axisymmetric structures like a bar, spiral arms and merger events can generate velocity fluctuations. Recent results using the APOGEE survey find significant fluctuations in velocity for stars in the midplane (|z|< 0.25 kpc) and out to 5 kpc, which suggests that the dynamical influence of the Milky Way's bar extends out to the Solar neighborhood. Their measured power spectrum has a characteristic amplitude of 11 km/s on a scale of ~ 2.5 kpc. The existence of large streaming motions on these scales has important implications for determining the Sun's motion about the Galactic Centre. Using red clump stars from the GALAH and APOGEE surveys, we map the line-of-sight velocity field around the Sun out to distances of 5 kpc and up to 1.25 kpc from the Galactic Plane. By subtracting a smooth axisymmetric model for the velocity field, we study the residual velocity fluctuations and compare our findings with mock survey generated by Galaxia based on an axisymmetric, steady state model. We find negligible large-scale fluctuations away from the plane. In the mid-plane, we reproduce the earlier APOGEE power spectrum results but with 20\% smaller amplitude (9.5 km/s) after taking a few systematic effects into account (e.g. volume completeness). The amplitude power is further reduced to 6.7 km/s if a flexible axisymmetric model is used. Additionally, our mock simulations show that, in the plane, the distances are underestimated for high mass red clump stars and this can lead to spurious power with amplitude of about 5.5 km/s. Taking this into account, we estimate the amplitude of real fluctuations to be less than 4.2 km/s, about a factor of three less than the previous result from APOGEE
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