609 research outputs found

    Beyond galaxy bimodality: the complex interplay between kinematic morphology and star formation in the local Universe

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    It is generally assumed that galaxies are a bimodal population in both star formation and structure: star-forming galaxies are disks, while passive galaxies host large bulges or are entirely spheroidal. Here, we test this scenario by presenting a full census of the kinematic morphologies of a volume-limited sample of galaxies in the local Universe extracted from the MaNGA galaxy survey. We measure the integrated stellar line-of-sight velocity to velocity dispersion ratio (V/σV/\sigma) for 4574 galaxies in the stellar mass range 9.75<log⁡M⋆[M⊙]<11.759.75 < \log M_{\star}[\rm{M}_{\odot}] < 11.75. We show that at fixed stellar mass, the distribution of V/σV/\sigma is not bimodal, and that a simple separation between fast and slow rotators is over-simplistic. Fast rotators are a mixture of at least two populations, referred to here as dynamically-cold disks and intermediate systems, with disks dominating in both total stellar mass and number. When considering star-forming and passive galaxies separately, the star-forming population is almost entirely made up of disks, while the passive population is mixed, implying an array of quenching mechanisms. Passive disks represent ∼\sim30% (both in number and mass) of passive galaxies, nearly a factor of two higher than that of slow rotators, reiterating that these are an important population for understanding galaxy quenching. These results paint a picture of a local Universe dominated by disky galaxies, most of which become somewhat less rotation-supported upon or after quenching. While spheroids are present to a degree, they are certainly not the evolutionary end-point for the majority of galaxies.Comment: 17 pages (incl. 5 of appendix), accepted for publication in Ap

    A photometrically and spectroscopically confirmed population of passive spiral galaxies

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    We have identified a population of passive spiral galaxies from photometry and integral field spectroscopy. We selected z < 0.035 spiral galaxies that have WISE colours consistent with little mid-infrared emission from warm dust. Matched aperture photometry of 51 spiral galaxies in ultraviolet, optical and mid-infrared show these galaxies have colours consistent with passive galaxies. Six galaxies form a spectroscopic pilot study and were observed using the Wide-Field Spectrograph to check for signs of nebular emission from star formation. We see no evidence of substantial nebular emission found in previous red spiral samples. These six galaxies possess absorption-line spectra with 4000 Å breaks consistent with an average luminosity-weighted age of 2.3 Gyr. Our photometric and integral field spectroscopic observations confirm the existence of a population of local passive spiral galaxies, implying that transformation into early-type morphologies is not required for the quenching of star formation

    An unusual “venous circle” of the internal mammary vein encountered during microvascular anastomosis and implications for practice

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    The internal mammary vessels are commonly used for anastomosis in breast reconstruction. The anatomy when using the 2nd ICS has been shown to be predictable and hence preferentially used by the senior author. We present an unusual case of internal mammary vein bifurcation and immediate confluence forming a ‘venous circle’

    The drivers of AGN activity in galaxy clusters: AGN fraction as a function of mass and environment

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    We present an analysis of optical spectroscopically identified active galactic nuclei (AGN) down to a cluster magnitude of M * + 1 in a sample of six self-similar Sloan Digital Sky Survey galaxy clusters at z ~ 0.07. These clusters are specifically selected to lack significant substructure at bright limits in their central regions so that we are largely able to eliminate the local action of merging clusters on the frequency of AGN. We demonstrate that the AGN fraction increases significantly from the cluster centre to 1.5R virial , but tails off at larger radii. If only comparing the cluster core region to regions at ~2R virial , no significant variation would be found. We compute the AGN fraction by mass and show that massive galaxies (log(stellarmass) > 10.7) are host to a systematically higher fraction of AGN than lower mass galaxies at all radii from the cluster centre. We attribute this deficit of AGN in the cluster centre to the changing mix of galaxy types with radius. We use the WHAN diagnostic to separate weak AGN from 'retired' galaxies in which the main ionization mechanism comes from old stellar populations. These retired AGN are found at all radii, while the mass effect is much more pronounced: we find that massive galaxies are more likely to be in the retired class. Further, we show that our AGN have no special position inside galaxy clusters - they are neither preferentially located in the infall regions nor situated at local maxima of galaxy density as measured with ∑ 5 . However, we find that the most powerful AGN (with [O III] equivalent widths < -10 Å) reside at significant velocity offsets in the cluster, and this brings our analysis into agreement with previous work on X-ray-selected AGN. Our results suggest that if interactions with other galaxies are responsible for triggering AGN activity, the time lag between trigger and AGN enhancement must be sufficiently long to obfuscate the encounter site and wipe out the local galaxy density signal. © 2012 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society

    The Value of Admission Clinical Data for Diagnosing Heart Failure in Long-term Care

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    Background Heart failure (HF) is common in long-term care (LTC). Diagnostic uncertainty is important barrier to optimal HF management, stemming from inadequate health information transfer upon LTC admission. We determine the utility of admission clinical information to confirm a HF diagnosis in new LTC residents. Methods This was a prospective cohort study. From February 2004 to November 2006, information about new residents from 41 LTC homes in Ontario, Canada, was collected from residents and caregivers, and all available health records. A prior HF diagnosis was confirmed by consensus review of available data by two independent experts. Multivariate modelling was utilized to determine the utility of the admission clinical assessment in confirming a prior HF diagnosis. Results A total of 449 residents were included for analysis, aged84.3±6.5 years, and 21.6% had a prior HF diagnosis. The most useful clinical item for diagnosing HF was a “history of HF”. The final model included “history of HF’ (OR [odds ratio] 13.66, 95% CI 6.61–28.24), “fluid on the lungs” (OR 2.01, 95% CI 1.04–3.89), “orthopnea” (OR 1.76, 95% CI 0.93–3.33), “taking β-blocker” (OR 2.09, 95% CI 1.10– 3.94), “taking loop diuretics” (OR 2.11, 95% CI 1.12–3.98), and “history of coronary artery disease” (OR 2.83, 95% CI 1.42–5.64). Conclusion Elements of the clinical assessment for new LTC residents can help confirm a prior HF diagnosis. An admission history of HF is highly predictiveCanadian Institutes of Health Research (CIHR; Study ID 117947-BCA-CEBA-126289

    Wave propagation in stereo-lithographical (STL) bone replicas at oblique incidence

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    Comparisons between predictions of a Biot-Allard model allowing for angle-dependent elasticity and angle-and-porosity dependent tortuosity and transmission data obtained at normal incidence on water-saturated replica bones are extended to oblique incidence. The model includes two parameters which are adjusted for best fit at normal incidence. Using the same parameter values, it is found that predictions of the variation of transmitted waveforms with angle through two types of bone replica are in reasonable agreement with data despite the fact that scattering is not included in the theory

    Heterogeneity of inverted calcium II H:K ratio cluster galaxies

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    © 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society The ratio of calcium II H plus H∊ to calcium II K inverts as a galaxy stellar population moves from being dominated by older stars to possessing more A and B class stars. This ratio – the H:K ratio – can serve as an indicator of stellar populations younger than 200 Myr. In this work, we provide a new method to determine H:K, and apply it to spectra taken of cluster galaxies in Abell 3888. Although H:K is on average systematically lower for the cluster than for a wider field sample, we show that H:K does not have a simple relationship with other indices such as the equivalent widths of Hδ and [O II] beyond having a high value for strong [O II] emission. Moreover, strongly inverted galaxies with H:K > 1.1 have no preferred location within the cluster and are only slightly lower in their velocity dispersions around the cluster compared to strongly emitting [O II] galaxies. Our results indicate that selecting galaxies on H:K inversion results in a heterogeneous sample formed via a mixture of pathways that likely includes, but may not be limited to, merging spiral galaxies, and quiescent galaxies accreting lower mass, gas-rich companions. In concert with other selection criteria, H:K can provide a means to select a more ‘pure’ passive sample or to aid in the selection of highly star-forming galaxies, especially where other spectral line indicators such as H α may not have been observed

    Heart Failure in Older Persons: Considerations For The Primary Care Physician

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    Heart failure (HF) affects over 500,000 Canadians, with 50,000 new patients diagnosed each year. While mortality from cardiovascular diseases has progressively declined in Canada, the burden of HF is expected to continue rising as a result of population aging and improved survival of patients with other cardiovascular diseases. HF is the leading cause of hospitalization and death among those aged 65 years and over, with a mortality rate of up to 50% within 5 years of diagnosis. Elderly HF patients are complex: a recent Ontario study of home care recipients with HF found that these clients had more health instability, took more medications, and had more co-morbidities compared with other home care clients. Optimal management of HF in “complex seniors” requires that clinicians understand the interactions between HF and age-associated syndromes such as frailty, cognitive impairment, and functional decline. As the majority of Canadian patients with HF are treated by primary care providers (PCPs), this article is directed at PCPs caring for older adults with HF. It is meant as a brief overview and discusses how the Canadian Cardiovascular Society (CCS) Consensus Guidelines on HF can be applied in daily practice

    The Ursinus Weekly, May 2, 1955

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    Spring play May 12-14 in T-G gym • Y installs officers at vespers Sunday • Pre-meds to hear polio expert tonite • Hamilton to head pre-legal society • Meistersingers end season with Music for you • National music frat installed at Ursinus • Mass rehearsals listed for May Day • Y retreat at Mensch Mill; New cabinet assumes duties • Pictures taken of college X-day • Mr. L. Krug heads C-T school district • Sasha Siemal tells of jaguar hunting • \u2756 Ruby will take Spring sports pictures tomorrow • Editorials: Here\u27s a spot for you • Letters to the editor • Dining-room has unusual guest • Fraternity row • Thinclads lose again despite victories by Herwig, Lawhead • Fords blank Bruin netmen in 9-0 rout • Girls tie record with 3-2 net win • Bruins smash Dickinson; Edge Fords in 4-3 contest • Sholl\u27s hit wins 1-0 mound duel • Dr. Franklin Watts speaks to WRC • Canterbury Club visits Preventorium • A.P.O. waits until Fall for charter • Debaters beat Haverfordhttps://digitalcommons.ursinus.edu/weekly/1473/thumbnail.jp
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