2,697 research outputs found
Optical Spectroscopic Survey of High-latitude WISE-selected Sources
We report on the results of an optical spectroscopic survey at high Galactic latitude (|b| ā„ 30Ā°) of a sample of WISE-selected targets, grouped by WISE W1 (Ī»_eff = 3.4 Ī¼m) flux, which we use to characterize the sources WISE detected. We observed 762 targets in 10 disjoint fields centered on ultraluminous infrared galaxy candidates using DEIMOS on Keck II. We find 0.30 Ā± 0.02 galaxies arcminā2 with a median redshift of z = 0.33 Ā± 0.01 for the sample with W1 ā„ 120 Ī¼Jy. The foreground stellar densities in our survey range from 0.23 Ā± 0.07 arcminā2 to 1.1 Ā± 0.1 arcminā2 for the same sample. We obtained spectra that produced science grade redshifts for ā„90% of our targets for sources with W1 flux ā„120 Ī¼Jy that also had an i-band flux gsim 18 Ī¼Jy. We used this for targeting very preliminary data reductions available to the team in 2010 August. Our results therefore present a conservative estimate of what is possible to achieve using WISE's Preliminary Data Release for the study of field galaxies
Morphological Classification of Local Luminous Infrared Galaxies
We present an analysis of the morphological classification of 89 luminous
infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey
(GOALS) sample using non-parametric coefficients and compare their morphology
as a function of wavelength. We rely on images obtained in the optical (B- and
I-band) as well as in the infrared (H-band and 5.8m). Our classification
is based on the calculation of and the second order of light ()
non-parametric coefficients which we explore as a function of stellar mass
(), infrared luminosity () and star formation rate (SFR). We
investigate the relation between , the specific SFR (sSFR) and the dust
temperature () in our galaxy sample. We find that is a
better morphological tracer than , as it allows to distinguish systems
formed by double systems from isolated and post-merger LIRGs. The
multi-wavelength analysis allows us to identify a region in the -
parameter space where ongoing mergers reside, regardless of the band used to
calculate the coefficients. In particular when measured in the H-band, this
region can be used to identify ongoing mergers, with a minimal contamination
from LIRGs in other stages. We also find that while the sSFR is positively
correlated with when measured in the mid-infrared, i.e. star-bursting
galaxies show more compact emission, it is anti-correlated with the B-band
based . We interpret this as the spatial decoupling between obscured
and un-obscured star formation, whereby the ultraviolet/optical size of a LIRGs
experience an intense dust enshrouded central starburst is larger than in the
one in the mid-infrared since the contrast between the nuclear to the extended
disk emission is smaller in the mid-infrared. This has important implications
for high redshift surveys of dusty sources. [abridged]Comment: ( 18 pages, 12 figures, Accepted for publication in A&A
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On Visible Homelessness and the Micro-Aesthetics of Public Space
In this article, we investigate the circumstances that have produced the current municipal regulatory approach to homelessness in the City of Melbourne, Victoria, and the ways in which visibly homeless people are policed through a micro-aesthetics of their presence in public space, which involves the monitoring of their bodily demeanour and their physical possessions. Our study contributes to and draws from a range of debates, including studies of the governmental conjunction of poverty and crime, analysis of the co-implication of law and spatiality, research on the criminalisation of homelessness and homeless people, and the burgeoning criminological interest in the significance of the visual field for our understandings of crime and criminality. This article recounts how homelessness, public space and questions of aesthetics have recently coalesced in debates about the regulation of homelessness in the public space of Melbourneās city centre. It approaches the issues through comparative consideration of genres of municipal management frameworks in other jurisdictions, detailed textual consideration of the Protocol on Homelessness in the City of Melbourne and an empirical study of visible homelessness in the public places of central Melbourne
The Deep Space Network: A Radio Communications Instrument for Deep Space Exploration
The primary purpose of the Deep Space Network (DSN) is to serve as a communications instrument for deep space exploration, providing communications between the spacecraft and the ground facilities. The uplink communications channel provides instructions or commands to the spacecraft. The downlink communications channel provides command verification and spacecraft engineering and science instrument payload data
Mid-infrared Selection of Active Galactic Nuclei with the Wide-Field Infrared Survey Explorer. I. Characterizing WISE-selected Active Galactic Nuclei in COSMOS
The Wide-field Infrared Survey Explorer (WISE) is an extremely capable and efficient black hole finder. We present a simple mid-infrared color criterion, W1 ā W2 ā„ 0.8 (i.e., [3.4]ā[4.6] ā„0.8, Vega), which identifies 61.9 Ā± 5.4 active galactic nucleus (AGN) candidates per deg^2 to a depth of W2 ~ 15.0. This implies a much larger census of luminous AGNs than found by typical wide-area surveys, attributable to the fact that mid-infrared selection identifies both unobscured (type 1) and obscured (type 2) AGNs. Optical and soft X-ray surveys alone are highly biased toward only unobscured AGNs, while this simple WISE selection likely identifies even heavily obscured, Compton-thick AGNs. Using deep, public data in the COSMOS field, we explore the properties of WISE-selected AGN candidates. At the mid-infrared depth considered, 160 Ī¼Jy at 4.6 Ī¼m, this simple criterion identifies 78% of Spitzer mid-infrared AGN candidates according to the criteria of Stern et al. and the reliability is 95%. We explore the demographics, multiwavelength properties and redshift distribution of WISE-selected AGN candidates in the COSMOS field
Measuring surface-area-to-volume ratios in soft porous materials using laser-polarized xenon interphase exchange NMR
We demonstrate a minimally invasive nuclear magnetic resonance (NMR)
technique that enables determination of the surface-area-to-volume ratio (S/V)
of soft porous materials from measurements of the diffusive exchange of
laser-polarized 129Xe between gas in the pore space and 129Xe dissolved in the
solid phase. We apply this NMR technique to porous polymer samples and find
approximate agreement with destructive stereological measurements of S/V
obtained with optical confocal microscopy. Potential applications of
laser-polarized xenon interphase exchange NMR include measurements of in vivo
lung function in humans and characterization of gas chromatography columns.Comment: 14 pages of text, 4 figure
āDonāt just travelā: thinking poetically on the way to professional knowledge
This paper describes how the medium of āfound poetryā is incorporated into a doctoral programme for nurses, educators and allied health and social care professionals at the start of their various doctoral journeys. It advocates a narrative practice approach to issues of researcher identity and reflexivity. āFindingā the poems begins with the creation of collages as representational anchors for students to talk about themselves, their professional practice, their hopes and expectations of the doctoral experience, and their research ideas. (Re)presenting their transcribed talk as poetry involves culling and playing with words, phrases and segments, making changes in spacing, lines and rhythm to arrive at an evocative distillation (Butler-Kisber, 2002). This process enables each person to bring stories and/or fragments of experience into critical engagement with others. Poetic thinking functions pedagogically, helping students find a critical voice to enliven and hone their reflexive writing in relation to their doctoral experience and their research positioning. Arts-based methods of inquiry are an ongoing topic of interest in research communities. Found poetry is a useful starting point to explore creative means by which research participants can recount their stories, and equally, by which researchers can witness and disseminate what they have to tell.self funde
Academic medical center clinical research professional workforce: Part 2 - issues in staff onboarding and professional development
Background: Defining key barriers to the development of a well-trained clinical research professional (CRP) workforce is an essential first step in identifying solutions for successful CRP onboarding, training, and competency development, which will enhance quality across the clinical and translational research enterprise. This study aimed to summarize barriers and best practices at academic medical centers related to effective CRP onboarding, training, professional development, identify challenges with the assessment of and mentoring for CRP competency growth, and describe opportunities to improve training and professionalization for the CRP career pathway.
Materials/Methods: Qualitative data from a series of Un-Meeting breakout sessions and open-text survey questions were analyzed to explore the complex issues involved when developing high-quality onboarding and continuing education opportunities for CRPs at academic medical centers.
Results: Results suggest there are several barriers to training the CRP workforce, including balancing foundational onboarding with role-based training, managing logistical challenges and institutional contexts, identifying/enlisting institutional champions, assessing competency, and providing high-quality mentorship. Several of these themes are interrelated. Two universal threads present throughout all themes are the need for effective communication and the need to improve professionalization of the CRP career pathway.
Conclusion: Few institutions have solved all the issues related to training a competent and adaptable CRP workforce, although some have addressed one or more. We applied a socio-technical lens to illustrate our findings and the need for NCATS-funded academic medical centers to work collaboratively within and across institutions to overcome training barriers and support a vital, well-qualified workforce and present several exemplars from the field to help attain this goal
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