421 research outputs found
Working with Linguistically Diverse Classes across the Disciplines: Faculty Beliefs
The rapid growth of international students at United States universities in recent years (Institute of International Education, 2013) has prompted discussions about how best to serve this population in and out of the classroom. This article reports on faculty cognitions (Borg, 2006) regarding internationalization and the teaching of international students who are emergent multilinguals. Researchers surveyed faculty members on one campus about their beliefs regarding internationalization, techniques for instruction in culturally and linguistically diverse classrooms, and their own efficacy in teaching international students. Results indicate a theory-reality split in beliefs about internationalization and techniques for teaching international students along with relatively low levels of self-efficacy in working with emergent multilinguals. The article discusses implications for faculty-administration collaboration and faculty development in linguistically-responsive instruction
Examining the Role of Environment in a Comprehensive Sample of Compact Groups
(Abridged) Compact groups, with their high number densities, small velocity
dispersions, and an interstellar medium that has not been fully processed,
provide a local analog to conditions of galaxy interactions in the earlier
universe. The frequent and prolonged gravitational encounters that occur in
compact groups affect the evolution of the constituent galaxies in a myriad of
ways, for example gas processing and star formation. Recently, a statistically
significant "gap" has been discovered mid-infrared IRAC colorspace of compact
group galaxies. This gap is not seen in field samples and is a new example of
how the compact group environment may affect the evolution of member galaxies.
In order to investigate the origin and nature of this gap, we have compiled a
sample of 49 compact groups. We find that a statistically significant deficit
of galaxies in this gap region of IRAC colorspace is persistant in this sample,
lending support to the hypothesis that the compact group environment inhibits
moderate SSFRs. We note a curvature in the colorspace distribution, which is
fully consistent with increasing dust temperature as the activity in a galaxy
increases. This full sample of 49 compact groups allows us to subdivide the
data according to physical properties of the groups. An analysis of these
subsamples indicates that neither projected physical diameter nor density show
a trend in colorspace within the values represented by this sample. We
hypothesize that the apparent lack of a trend is due to the relatively small
range of properties in this sample. Thus, the relative influence of stochastic
effects becomes dominant. We analyze spectral energy distributions of member
galaxies as a function of their location in colorspace and find that galaxies
in different regions of MIR colorspace contain dust with varying temperatures
and/or PAH emission.Comment: 24 pages, 13 figures. Accepted for publication in The Astronomical
Journa
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Exposure-Lag-Response in Longitudinal Studies: Application of Distributed-Lag Nonlinear Models in an Occupational Cohort.
Prolonged exposures can have complex relationships with health outcomes, as timing, duration, and intensity of exposure are all potentially relevant. Summary measures such as cumulative exposure or average intensity of exposure may not fully capture these relationships. We applied penalized and unpenalized distributed-lag nonlinear models (DLNMs) with flexible exposure-response and lag-response functions in order to examine the association between crystalline silica exposure and mortality from lung cancer and nonmalignant respiratory disease in a cohort study of 2,342 California diatomaceous earth workers followed during 1942-2011. We also assessed associations using simple measures of cumulative exposure assuming linear exposure-response and constant lag-response. Measures of association from DLNMs were generally higher than those from simpler models. Rate ratios from penalized DLNMs corresponding to average daily exposures of 0.4 mg/m3 during lag years 31-50 prior to the age of observed cases were 1.47 (95% confidence interval (CI): 0.92, 2.35) for lung cancer mortality and 1.80 (95% CI: 1.14, 2.85) for nonmalignant respiratory disease mortality. Rate ratios from the simpler models for the same exposure scenario were 1.15 (95% CI: 0.89, 1.48) and 1.23 (95% CI: 1.03, 1.46), respectively. Longitudinal cohort studies of prolonged exposures and chronic health outcomes should explore methods allowing for flexibility and nonlinearities in the exposure-lag-response
Some Like It Hot: Linking Diffuse X-ray Luminosity, Baryonic Mass, and Star Formation Rate in Compact Groups of Galaxies
We present an analysis of the diffuse X-ray emission in 19 compact groups of
galaxies (CGs) observed with Chandra. The hottest, most X-ray luminous CGs
agree well with the galaxy cluster X-ray scaling relations in and
, even in CGs where the hot gas is associated with only the
brightest galaxy. Using Spitzer photometry, we compute stellar masses and
classify HCGs 19, 22, 40, and 42 and RSCGs 32, 44, and 86 as fossil groups
using a new definition for fossil systems that includes a broader range of
masses. We find that CGs with total stellar and HI masses
M are often X-ray luminous, while lower-mass CGs only sometimes exhibit
faint, localized X-ray emission. Additionally, we compare the diffuse X-ray
luminosity against both the total UV and 24 m star formation rates of each
CG and optical colors of the most massive galaxy in each of the CGs. The most
X-ray luminous CGs have the lowest star formation rates, likely because there
is no cold gas available for star formation, either because the majority of the
baryons in these CGs are in stars or the X-ray halo, or due to gas stripping
from the galaxies in CGs with hot halos. Finally, the optical colors that trace
recent star formation histories of the most massive group galaxies do not
correlate with the X-ray luminosities of the CGs, indicating that perhaps the
current state of the X-ray halos is independent of the recent history of
stellar mass assembly in the most massive galaxies.Comment: 20 pages, 7 figures, accepted for publication in Ap
Global Properties of Neutral Hydrogen in Compact Groups
Compact groups of galaxies provide a unique environment to study the
evolution of galaxies amid frequent gravitational encounters. These nearby
groups have conditions similar to those in the earlier universe when galaxies
were assembled and give us the opportunity to witness hierarchical formation in
progress. To understand how the compact group environment affects galaxy
evolution, we examine the gas and dust in these groups. We present new
single-dish GBT neutral hydrogen (HI) observations of 30 compact groups and
define a new way to quantify the group HI content as the HI-to-stellar mass
ratio of the group as a whole. We compare the HI content with mid-IR indicators
of star formation and optical [g-r] color to search for correlations between
group gas content and star formation activity of individual group members.
Quiescent galaxies tend to live in HI-poor groups, and galaxies with active
star formation are more commonly found in HI-rich groups. Intriguingly, we also
find "rogue" galaxies whose star formation does not correlate with group HI
content. In particular, we identify three galaxies (NGC 2968 in RSCG 34, KUG
1131+202A in RSCG 42, and NGC 4613 in RSCG 64) whose mid-IR activity is
discrepant with the HI. We speculate that this mismatch between mid-IR activity
and HI content is a consequence of strong interactions in this environment that
can strip HI from galaxies and abruptly affect star-formation. Ultimately,
characterizing how and on what timescales the gas is processed in compact
groups will help us understand the interstellar medium in complex, dense
environments similar to the earlier Universe.Comment: Accepted to A
Working with Linguistically Diverse Classes across the Disciplines: Faculty Beliefs
The rapid growth of international students at United States universities in recent years (Institute of International Education, 2013) has prompted discussions about how best to serve this population in and out of the classroom. This article reports on faculty cognitions (Borg, 2006) regarding internationalization and the teaching of international students who are emergent multilinguals. Researchers surveyed faculty members on one campus about their beliefs regarding internationalization, techniques for instruction in culturally and linguistically diverse classrooms, and their own efficacy in teaching international students. Results indicate a theory-reality split in beliefs about internationalization and techniques for teaching international students along with relatively low levels of self-efficacy in working with emergent multilinguals. The article discusses implications for faculty-administration collaboration and faculty development in linguistically-responsive instruction
Mid-Infrared Evidence for Accelerated Evolution in Compact Group Galaxies
We find evidence for accelerated evolution in compact group galaxies from the
distribution in mid-infrared colorspace of 42 galaxies from 12 Hickson Compact
Groups (HCGs) compared to the the distributions of several other samples
including the LVL+SINGS galaxies, interacting galaxies, and galaxies from the
Coma Cluster. We find that the HCG galaxies are not uniformly distributed in
colorspace, as well as quantitative evidence for a gap. Galaxies in the infall
region of the Coma cluster also exhibit a non-uniform distribution and a less
well defined gap, which may reflect a similarity with the compact group
environment. Neither the Coma Center or interacting samples show evidence of a
gap, leading us to speculate that the gap is unique to the environment of high
galaxy density where gas has not been fully processed or stripped.Comment: To appear in the Proceedings of the Galaxy Wars: Stellar Populations
and Star Formation in Interacting Galaxies Conferenc
Design of a Novel Low Cost Point of Care Tampon (POCkeT) Colposcope for Use in Resource Limited Settings
Introduction: Current guidelines by WHO for cervical cancer screening in low- and middle-income countries involves visual inspection with acetic acid (VIA) of the cervix, followed by treatment
during the same visit or a subsequent visit with cryotherapy if a suspicious lesion is found.
Implementation of these guidelines is hampered by a lack of: trained health workers, reliable
technology, and access to screening facilities. A low cost ultra-portable Point of Care Tampon
based digital colposcope (POCkeT Colposcope) for use at the community level setting,
which has the unique form factor of a tampon, can be inserted into the vagina to capture
images of the cervix, which are on par with that of a state of the art colposcope, at a fraction
of the cost. A repository of images to be compiled that can be used to empower front line
workers to become more effective through virtual dynamic training. By task shifting to the
community setting, this technology could potentially provide significantly greater cervical
screening access to where the most vulnerable women live. The POCkeT Colposcope’s
concentric LED ring provides comparable white and green field illumination at a fraction of
the electrical power required in commercial colposcopes. Evaluation with standard optical
imaging targets to assess the POCkeT Colposcope against the state of the art digital colposcope
and other VIAM technologies. Results: Our POCkeT Colposcope has comparable resolving power, color reproduction accuracy, minimal lens distortion, and illumination when compared to commercially available colposcopes. In vitro and pilot in vivo imaging results are promising with our POCkeT Colposcope capturing comparable quality images to commercial systems.
Methods: Rapid 3D printing, consumer grade light sources, and cameras were used to construct the TVDC. The TVDC’s concentric LED ring provides comparable white and green field illumination at a fraction of the electrical power required in commercial colposcopes, and crossed polarizers provide a reduction in glare. Evaluation was performed using standard optical imaging targets to assess the TVDC against the state of the art digital colposcope and other VIA technologies.
Results: Our TVDC has comparable resolving power, color reproduction accuracy, minimal lens distortion, and illumination when compared to commercially available colposcopes. In vitro and pilot in vivo imaging results are promising with our TVDC capturing images of comparable quality to commercial systems.
Conclusion: The TVDC is capable of capturing images suitable for cervical lesion analysis. Our portable low cost system will be useful for increasing access to cervical cancer screening and diagnostics in resource-limited settings by providing a more readily portable and easy to use device for medical personnel.The image data and support information that is published in the article "Design of a Novel Low Cost Trans-Vaginal Digital Colposcope for use in Resource Limited Settings" are available at: http://dukespace.lib.duke.edu/dspace/handle/10161/8357.National Institutes of Health (US) 5R21CA162747-0
In Defence of Modest Doxasticism About Delusions
Here I reply to the main points raised by the commentators on the arguments put forward in my Delusions and Other Irrational Beliefs (OUP, 2009). My response is aimed at defending a modest doxastic account of clinical delusions, and is articulated in three sections. First, I consider the view that delusions are in-between perceptual and doxastic states, defended by Jacob Hohwy and Vivek Rajan, and the view that delusions are failed attempts at believing or not-quite-beliefs, proposed by Eric Schwitzgebel and Maura Tumulty. Then, I address the relationship between the doxastic account of delusions and the role, nature, and prospects of folk psychology, which is discussed by Dominic Murphy, Keith Frankish, and Maura Tumulty in their contributions. In the final remarks, I turn to the continuity thesis and suggest that, although there are important differences between clinical delusions and non-pathological beliefs, these differences cannot be characterised satisfactorily in epistemic terms. \u
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