5,789 research outputs found
First Science Results From SOFIA/FORCAST: Super-Resolution Imaging of the S140 Cluster at 37\micron
We present 37\micron\ imaging of the S140 complex of infrared sources
centered on IRS1 made with the FORCAST camera on SOFIA. These observations are
the longest wavelength imaging to resolve clearly the three main sources seen
at shorter wavelengths, IRS 1, 2 and 3, and are nearly at the diffraction limit
of the 2.5-m telescope. We also obtained a small number of images at 11 and
31\micron\ that are useful for flux measurement. Our images cover the area of
several strong sub-mm sources seen in the area -- SMM 1, 2, and 3 -- that are
not coincident with any mid-infrared sources and are not visible in our longer
wavelength imaging either. Our new observations confirm previous estimates of
the relative dust optical depth and source luminosity for the components in
this likely cluster of early B stars. We also investigate the use of
super-resolution to go beyond the basic diffraction limit in imaging on SOFIA
and find that the van Cittert algorithm, together with the "multi-resolution"
technique, provides excellent results
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Prevalence of iron deficiency in 62,685 women of seven race/ethnicity groups: The HEIRS Study.
BackgroundFew cross-sectional studies report iron deficiency (ID) prevalence in women of different race/ethnicity and ages in US or Canada.Materials and methodsWe evaluated screening observations on women who participated between 2001-2003 in a cross-sectional, primary care-based sample of adults ages ≥25 y whose observations were complete: race/ethnicity; age; transferrin saturation; serum ferritin; and HFE p.C282Y and p.H63D alleles. We defined ID using a stringent criterion: combined transferrin saturation <10% and serum ferritin <33.7 pmol/L (<15 μg/L). We compared ID prevalence in women of different race/ethnicity subgrouped by age and determined associations of p.C282Y and p.H63D to ID overall, and to ID in women ages 25-44 y with or without self-reported pregnancy.ResultsThese 62,685 women included 27,079 whites, 17,272 blacks, 8,566 Hispanics, 7,615 Asians, 449 Pacific Islanders, 441 Native Americans, and 1,263 participants of other race/ethnicity. Proportions of women with ID were higher in Hispanics and blacks than whites and Asians. Prevalence of ID was significantly greater in women ages 25-54 y of all race/ethnicity groups than women ages ≥55 y of corresponding race/ethnicity. In women ages ≥55 y, ID prevalence did not differ significantly across race/ethnicity. p.C282Y and p.H63D prevalence did not differ significantly in women with or without ID, regardless of race/ethnicity, age subgroup, or pregnancy.ConclusionsID prevalence was greater in Hispanic and black than white and Asian women ages 25-54 y. p.C282Y and p.H63D prevalence did not differ significantly in women with or without ID, regardless of race/ethnicity, age subgroup, or pregnancy
Comparison of Winter Strawberry Production in a Commercial Heated High Tunnel versus a University Greenhouse
For the past 4 years, the University of Nebraska strawberry team has worked to develop low cost, sustainable methods for farmers and growers to produce strawberries in a double polyethylene greenhouse during the winter. This past year, this growing system was adapted to become a commercial grower’s heated high tunnel for the winter/spring of 2013-14. The idea was to scale up to a farm-size demonstration and compare it to the university greenhouse production system with a goal to expand marketing opportunities for strawberries into the winter season
POEMMA: Probe Of Extreme Multi-Messenger Astrophysics
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) mission is being
designed to establish charged-particle astronomy with ultra-high energy cosmic
rays (UHECRs) and to observe cosmogenic tau neutrinos (CTNs). The study of
UHECRs and CTNs from space will yield orders-of-magnitude increase in
statistics of observed UHECRs at the highest energies, and the observation of
the cosmogenic flux of neutrinos for a range of UHECR models. These
observations should solve the long-standing puzzle of the origin of the highest
energy particles ever observed, providing a new window onto the most energetic
environments and events in the Universe, while studying particle interactions
well beyond accelerator energies. The discovery of CTNs will help solve the
puzzle of the origin of UHECRs and begin a new field of Astroparticle Physics
with the study of neutrino properties at ultra-high energies.Comment: 8 pages, in the Proceedings of the 35th International Cosmic Ray
Conference, ICRC217, Busan, Kore
The prism model: advancing a theory of practice for arts and humanities in medical education
Introduction: The arts and humanities have transformative potential for medical education. Realizing this potential requires an understanding of what arts and humanities teaching is and what it aims to do. A 2016 review of exclusively quantitative studies mapped three discursive positions (art as intrinsic to, additive to or curative for medicine) and three epistemic functions (art for mastering skills, perspective taking, and personal growth and activism). A more inclusive sample might offer new insights into the position and function of arts and humanities teaching in medical education. Methods: Informed by this 2016 framework, we conducted discursive and conceptual analyses of 769 citations from a database created in a recent scoping review. We also analyzed the 15 stakeholder interviews from this review for recurring themes. These three analyses were iteratively compared and combined to produce a model representing the complex relationship among discursive functions and learning domains. Results: The literature largely positioned arts and humanities as additive to medicine and focused on the functions of mastering skills and perspective taking. Stakeholders emphasized the intrinsic value of arts and humanities and advocated their utility for social critique and change. We offer a refined theory of practice—the Prism Model of four functions (mastering skills, perspective taking, personal insight and social advocacy)—to support more strategic use of arts and humanities in medical education across all learning domains. Discussion: The Prism Model encourages greater pedagogical flexibility and critical reflection in arts and humanities teaching, offering a foundation for achieving its transformative potential
How are the arts and humanities used in medical education? Results of a scoping review
Purpose Although focused reviews have characterized subsets of the literature on the arts and humanities in medical education, a large-scale overview of the field is needed to inform efforts to strengthen these approaches in medicine. Method The authors conducted a scoping review in 2019 to identify how the arts and humanities are used to educate physicians and interprofessional learners across the medical education continuum in Canada and the United States. A search strategy involving 7 databases identified 21,985 citations. Five reviewers independently screened the titles and abstracts. Full-text screening followed (n = 4,649). Of these, 769 records met the inclusion criteria. The authors performed descriptive and statistical analyses and conducted semistructured interviews with 15 stakeholders. Results The literature is dominated by conceptual works (n = 294) that critically engaged with arts and humanities approaches or generally called for their use in medical education, followed by program descriptions (n = 255). The literary arts (n = 197) were most common. Less than a third of records explicitly engaged theory as a strong component (n = 230). Of descriptive and empirical records (n = 424), more than half concerned undergraduate medical education (n = 245). There were gaps in the literature on interprofessional education, program evaluation, and learner assessment. Programming was most often taught by medical faculty who published their initiatives (n = 236). Absent were voices of contributing artists, docents, and other arts and humanities practitioners from outside medicine. Stakeholders confirmed that these findings resonated with their experiences. Conclusions This literature is characterized by brief, episodic installments, privileging a biomedical orientation and largely lacking a theoretical frame to weave the installments into a larger story that accumulates over time and across subfields. These findings should inform efforts to promote, integrate, and study uses of the arts and humanities in medical education
Divergent Evolutionary Histories of DNA Markers in a Hawaiian Population of the Coral Montipora capitata
We investigated intra- and inter-colony sequence variation in a population of the dom- inant Hawaiian coral Montipora capitata by analyzing marker gene and genomic data. Ribosomal ITS1 regions showed evidence of a reticulate history among the colonies, suggesting incomplete rDNA repeat homogenization. Analysis of the mitochondrial genome identified a major (M. capitata) and a minor (M. flabellata) haplotype in single polyp-derived sperm bundle DNA with some colonies containing 2-3 different mtDNA haplotypes. In contrast, Pax-C and newly identified single-copy nuclear genes showed either no sequence differences or minor variations in SNP frequencies segregating among the colonies. Our data suggest past mitochondrial introgression in M. capitata, whereas nuclear single-copy loci show limited variation, highlighting the divergent evolutionary histories of these coral DNA markers
Momentum transfer using chirped standing wave fields: Bragg scattering
We consider momentum transfer using frequency-chirped standing wave fields.
Novel atom-beam splitter and mirror schemes based on Bragg scattering are
presented. It is shown that a predetermined number of photon momenta can be
transferred to the atoms in a single interaction zone.Comment: 4 pages, 3 figure
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