HI Observations of Five Groups of Galaxies

We present the results of HI observations of five groups of galaxies spanning a range of velocity dispersion and spiral fraction (brightest optical group member in parenthesis): NGC 7582 (NGC 7552), USGC U207 (NGC 2759), USGC U070 (NGC 664), USGC U412 (NGC 3822), USGC U451 (NGC 4065). Neutral intragroup gas is detected in three of the five groups. We present the discovery of a previously uncataloged galaxy in the USGC U070 group at RA(2000)= 01h45m27s, Dec(2000) = +04d36'19" which we are designating FSW J014526.92+043619.1. We compile an HI mass function for the group environment and find that the faint-end slope is consistent with being flat.Comment: 9 pages, 7 figures (slightly degraded in quality), emulateapj, accepted for publication in the Astronomical Journa

The Formation of Kiloparsec-scale HI Holes in Dwarf Galaxies

The origin of kpc-scale holes in the atomic hydrogen (H i) distributions of some nearby dwarf irregular galaxies presents an intriguing problem. Star formation histories (SFHs) derived from resolved stars give us the unique opportunity to study past star-forming events that may have helped shape the currently visible Hi distribution. Our sample of five nearby dwarf irregular galaxies spans over an order of magnitude in both total Hi mass and absolute B-band magnitude and is at the low-mass end of previously studied systems. We use Very Large Array Hi line data to estimate the energy required to create the centrally dominant hole in each galaxy. We compare this energy estimate to the past energy released by the underlying stellar populations computed from SFHs derived from data taken with the Hubble Space Telescope. The inferred integrated stellar energy released within the characteristic ages exceeds our energy estimates for creating the holes in all cases, assuming expected efficiencies. Therefore, it appears that stellar feedback provides sufficient energy to produce the observed holes. However, we find no obvious signature of single star-forming events responsible for the observed structures when comparing the global SFHs of each galaxy in our sample to each other or to those of dwarf irregular galaxies reported in the literature. We also fail to find evidence of a central star cluster in FUV or Hα imaging. We conclude that large Hi holes are likely formed from multiple generations of star formation and only under suitable interstellar medium conditions

How partnerships for community-based health professions training were affected by national changes in funding

Background: Area Health Education Centers (AHEC) have contributed to U.S. healthcare workforce training since 1971. National funders recently refocused efforts from K-12 students to matriculated health profession students, which reduced annual funding by $75,000 (25%) per year per Center. Objectives: To describe how community partnership changed due to funding reductions. Methods: Key informant interviews were conducted with all four regional center directors with community partnerships. Lessons learned: Hosted regional centers navigated partnerships in ways that did not significantly change programs because the host institutions supported continuing the partnerships. Independent centers experienced significant changes in partnerships by ending well-established programs and starting new programs with new partners. Both hosted and independent centers took salary cuts, downsized staff, and applied for grants and contracts to fill the funding gap. Improved communication with the Oregon AHEC program office was reported as needed. Conclusions: Navigating partnerships differed according to host status

Forming a large disc galaxy from a z < 1 major merger

Using high-resolution SPH simulations in a fully cosmological Λ cold dark matter context, we study the formation of a bright disc-dominated galaxy that originates from a ‘wet' major merger at z= 0.8. The progenitors of the disc galaxy are themselves disc galaxies that formed from early major mergers between galaxies with blue colours. A substantial thin stellar disc grows rapidly following the last major merger and the present-day properties of the final remnant are typical of early-type spiral galaxies, with an i-band bulge-to-disc ratio ∼0.65, a disc scalelength of 7.2 kpc, g−r= 0.5 mag, an H i linewidth (W20/2) of 238 km s−1 and total magnitude i=−22.4. The key ingredients for the formation of a dominant stellar disc component after a major merger are (i) substantial and rapid accretion of gas through cold flows followed at late times by cooling of gas from the hot phase, (ii) supernova feedback that is able to partially suppress star formation during mergers and (iii) relative fading of the spheroidal component. The gas fraction of the progenitors' discs does not exceed 25 per cent at z < 3, emphasizing that the continuous supply of gas from the local environment plays a major role in the regrowth of discs and in keeping the galaxies blue. The results of this simulation alleviate the problem posed for the existence of disc galaxies by the high likelihood of interactions and mergers for galaxy-sized haloes at relatively low

Economic models for sustainable interprofessional education

Limited information exists on funding models for interprofessional education (IPE) course delivery, even though potential savings from IPE could be gained in healthcare delivery efficiencies and patient safety. Unanticipated economic barriers to implementing an IPE curriculum across programs and schools in University settings can stymie or even end movement toward collaboration and sustainable culture change. Clarity among stakeholders, including institutional leadership, faculty, and students, is necessary to avoid confusion about IPE tuition costs and funds flow, given that IPE involves multiple schools and programs sharing space, time, faculty, and tuition dollars. In this paper, we consider three funding models for IPE: (a) Centralized (b) Blended, and (c) Decentralized. The strengths and challenges associated with each of these models are discussed. Beginning such a discussion will move us toward understanding the return on investment of IPE

Controlling the near-surface superfluid density in underdoped YBa₂Cu₃O_6+<i>x</i> by photo-illumination

The interaction with light weakens the superconducting ground state in classical superconductors. The situation in cuprate superconductors is more complicated: illumination increases the charge carrier density, a photo-induced effect that persists below room temperature. Furthermore, systematic investigations in underdoped YBa₂Cu₃O6+x (YBCO) have shown an enhanced critical temperature Tc. Until now, studies of photo-persistent conductivity (PPC) have been limited to investigations of structural and transport properties, as well as the onset of superconductivity. Here we show how changes in the magnetic screening profile of YBCO in the Meissner state due to PPC can be determined on a nanometer scale utilizing low-energy muons. The data obtained reveal a strongly increased superfluid density within the first few tens of nanometers from the sample surface. Our findings suggest a non-trivial modification of the near-surface band structure and give direct evidence that the superfluid density of YBCO can be controlled by light illumination

VLA-ANGST: A high-resolution HI Survey of Nearby Dwarf Galaxies

We present the "Very Large Array survey of Advanced Camera for Surveys Nearby Galaxy Survey Treasury galaxies (VLA-ANGST)." VLA-ANGST is a National Radio Astronomy Observatory Large Program consisting of high spectral (0.6-2.6 km/s) and spatial (~6") resolution observations of neutral, atomic hydrogen (HI) emission toward 35 nearby dwarf galaxies from the ANGST survey. ANGST is a systematic HST survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D\lesssim4 Mpc). VLA-ANGST provides VLA HI observations of the sub-sample of ANGST galaxies with recent star formation that are observable from the northern hemisphere and that were not observed in the "The HI Nearby Galaxy Survey" (THINGS). The overarching scientific goal of VLA-ANGST is to investigate fundamental characteristics of the neutral interstellar medium (ISM) of dwarf galaxies. Here we describe the VLA observations, the data reduction, and the final VLA-ANGST data products. We present an atlas of the integrated HI maps, the intensity-weighted velocity fields, the second moment maps as a measure for the velocity dispersion of the HI, individual channel maps, and integrated HI spectra for each VLA-ANGST galaxy. We closely follow the observational setup and data reduction of THINGS to achieve comparable sensitivity and angular resolution. A major difference, however, is the high velocity resolution of the VLA-ANGST observations (0.65 and 1.3km/s for the majority of the galaxies). The VLA-ANGST data products are made publicly available at: https://science.nrao.edu/science/surveys/vla-angst. With available star formation histories from resolved stellar populations and lower resolution ancillary observations from the FIR to the UV, VLA-ANGST will enable detailed studies of the relationship between the ISM and star formation in dwarf galaxies on a ~100 pc scale.Comment: 64 figures, grouped into 32. 115 pages, accepted for publication in the Astronomical Journa

Efficient Coding and Statistically Optimal Weighting of Covariance among Acoustic Attributes in Novel Sounds

To the extent that sensorineural systems are efficient, redundancy should be extracted to optimize transmission of information, but perceptual evidence for this has been limited. Stilp and colleagues recently reported efficient coding of robust correlation (r = .97) among complex acoustic attributes (attack/decay, spectral shape) in novel sounds. Discrimination of sounds orthogonal to the correlation was initially inferior but later comparable to that of sounds obeying the correlation. These effects were attenuated for less-correlated stimuli (r = .54) for reasons that are unclear. Here, statistical properties of correlation among acoustic attributes essential for perceptual organization are investigated. Overall, simple strength of the principal correlation is inadequate to predict listener performance. Initial superiority of discrimination for statistically consistent sound pairs was relatively insensitive to decreased physical acoustic/psychoacoustic range of evidence supporting the correlation, and to more frequent presentations of the same orthogonal test pairs. However, increased range supporting an orthogonal dimension has substantial effects upon perceptual organization. Connectionist simulations and Eigenvalues from closed-form calculations of principal components analysis (PCA) reveal that perceptual organization is near-optimally weighted to shared versus unshared covariance in experienced sound distributions. Implications of reduced perceptual dimensionality for speech perception and plausible neural substrates are discussed