584 research outputs found
He I λ10830 as a Probe of Winds in Accreting Young Stars
He I 10830 profiles acquired with Keck\u27s NIRSPEC for six young low-mass stars with high disk accretion rates (AS 353A, DG Tau, DL Tau, DR Tau, HL Tau, and SVS 13) provide new insight into accretion-driven winds. In four of the stars, the profiles have the signature of resonance scattering, and they possess a deep and broad blueshifted absorption that penetrates more than 50% into the 1 m continuum over a continuous range of velocities from near the stellar rest velocity to the terminal velocity of the wind, unlike inner wind signatures seen in other spectral features. This deep and broad absorption provides the first observational tracer of the acceleration region of the inner wind and suggests that this acceleration region is situated such that it occults a significant portion of the stellar disk. The remaining two stars also have blue absorption extending below the continuum, although here the profiles are dominated by emission, requiring an additional source of helium excitation beyond resonant scattering. This is likely the same process that produces the emission profiles seen at He I 5876 Å
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Food Insecurity in the Community College, a Phenomenological Inquiry: The Lived Experience of Students Using a Campus Food Pantry
The purpose of this study was to understand the lived experience of students to discern the impact of their interaction with the food pantry. This knowledge may, in turn, influence future food pantry methods and wider policy, both at PNW College and more broadly. Not only does student hunger have the potential to impact negatively student persistence and completion, but it represents an important equity issue on our higher ed campuses. By using phenomenological inquiry to explore the impact on student users of the campus food pantry, the following is the research question that was addressed: What are the lived experiences, perceptions, and educational impacts for community college students who use the food pantry at PNW College? This study was grounded in an interpretivist philosophical approach, which fits especially well with a phenomenological inquiry that asks students about their lived experiences with a food pantry on a community college campus. Ten interviews were analyzed using “in vivo” coding, and themes were determined using the students’ own words.
Themes that emerged from the study included challenges (food pantry barriers, educational obstacles, and stigma), survival attributes (strategy, resource, and findings), personal characteristics (resilience, caring, feelings, worry/apprehension, and self-sufficiency), and food pantry impacts (education/increased focus, validation, improved health). The results affirm the notion that non-academic barriers represent a significant concern among community college students. Additionally, findings indicate that the food pantry plays an important role on campus in supporting student health and focus on studies. Participants were found to be resilient and self-sufficient, and exhibited altruism toward other students. Contrary to popular thought, stigma emerged as almost a non-challenge; despite the prevailing idea that students using campus supports will feel ashamed, participants universally expressed a lack of concern with stigma. This study, which put students at the center of their own stories, offered several implications for future practice, policy, and research.
The practical significance of this study is potentially large. The study filled gaps in the literature where community colleges are not generally a focus, where qualitative research is rare, and where the voices of students themselves have been unheard. The role of the food pantry on college campuses in supporting student success is now widely recognized. This study is important, since it is vital for educators, administrators, and policy makers to understand student perceptions of food pantry use and its role as a support in their educational success. Particularly as we in higher education witness a push towards completion rather than mere enrollment, we must consider what populations are at risk. Optimistically, a focus on completion will mean a new push to remove non-academic barriers to student achievement that have long gone unaddressed. Food insecurity on higher ed campuses is a critical problem that undermines student success, but it is an issue that is within our collective power to overcome
Genetic testing and gene therapy in retinal diseases:Knowledge and perceptions of optometrists in Australia and New Zealand
The Grizzly, February 12, 1988
Harassment Runs Rampant • Security Tips for Safe Driving • Tapping the Task Force • Schroeder for Press • Sex Still Religiously Private • Letter: Commencing the Issue • Restructuring the Ursinus Tradition: Task Force Transcends Past Goals • Speech Exam Announced • Participants Model the U.N. • Winner-Take-All in Ursinus-Moravian Showdown • Hoopsters Vastly Improved • Reckless Wrestlers Rustlin\u27 Victory • The Bigger Doesn\u27t Mean the Better • Beam Breakin\u27 Benner • \u27Mers Keep Victory Abreast • Conwell Cuts the Cake • Reflect: Success Promising • Dole Doles out Compromise • Can\u27t a Person Change His Mind? • Race for the White House: The Candidateshttps://digitalcommons.ursinus.edu/grizzlynews/1204/thumbnail.jp
A strong-coupling analysis of two-dimensional O(N) sigma models with on square, triangular and honeycomb lattices
Recently-generated long strong-coupling series for the two-point Green's
functions of asymptotically free lattice models are
analyzed, focusing on the evaluation of dimensionless renormalization-group
invariant ratios of physical quantities and applying resummation techniques to
series in the inverse temperature and in the energy . Square,
triangular, and honeycomb lattices are considered, as a test of universality
and in order to estimate systematic errors. Large- solutions are carefully
studied in order to establish benchmarks for series coefficients and
resummations. Scaling and universality are verified. All invariant ratios
related to the large-distance properties of the two-point functions vary
monotonically with , departing from their large- values only by a few per
mille even down to .Comment: 53 pages (incl. 5 figures), tar/gzip/uuencode, REVTEX + psfi
Spin-Glass Theory for Pedestrians
In these notes the main theoretical concepts and techniques in the field of
mean-field spin-glasses are reviewed in a compact and pedagogical way, for the
benefit of the graduate and undergraduate student. One particular spin-glass
model is analyzed (the p-spin spherical model) by using three different
approaches. Thermodynamics, covering pure states, overlaps, overlap
distribution, replica symmetry breaking, and the static transition. Dynamics,
covering the generating functional method, generalized Langevin equation,
equations for the correlation and the response, the Mode Coupling
approximation, and the dynamical transition. And finally complexity, covering
the mean-field (TAP) free energy, metastable states, entropy crisis, threshold
energy, and saddles. Particular attention has been paid on the mutual
consistency of the results obtained from the different methods.Comment: Lecture notes of the school: "Unifying Concepts in Glassy Physics
III", Bangalore, June 200
Maternal corticotropin-releasing hormone is associated with LEP DNA methylation at birth and in childhood: an epigenome-wide study in Project Viva
BackgroundCorticotropin-releasing hormone (CRH) plays a central role in regulating the secretion of cortisol which controls a wide range of biological processes. Fetuses overexposed to cortisol have increased risks of disease in later life. DNA methylation may be the underlying association between prenatal cortisol exposure and health effects. We investigated associations between maternal CRH levels and epigenome-wide DNA methylation of cord blood in offsprings and evaluated whether these associations persisted into mid-childhood.MethodsWe investigated mother-child pairs enrolled in the prospective Project Viva pre-birth cohort. We measured DNA methylation in 257 umbilical cord blood samples using the HumanMethylation450 Bead Chip. We tested associations of maternal CRH concentration with cord blood cells DNA methylation, adjusting the model for maternal age at enrollment, education, maternal race/ethnicity, maternal smoking status, pre-pregnancy body mass index, parity, gestational age at delivery, child sex, and cell-type composition in cord blood. We further examined the persistence of associations between maternal CRH levels and DNA methylation in children's blood cells collected at mid-childhood (n = 239, age: 6.7-10.3 years) additionally adjusting for the children's age at blood drawn.ResultsMaternal CRH levels are associated with DNA methylation variability in cord blood cells at 96 individual CpG sites (False Discovery Rate <0.05). Among the 96 CpG sites, we identified 3 CpGs located near the LEP gene. Regional analyses confirmed the association between maternal CRH and DNA methylation near LEP. Moreover, higher maternal CRH levels were associated with higher blood-cell DNA methylation of the promoter region of LEP in mid-childhood (P < 0.05, β = 0.64, SE = 0.30).ConclusionIn our cohort, maternal CRH was associated with DNA methylation levels in newborns at multiple loci, notably in the LEP gene promoter. The association between maternal CRH and LEP DNA methylation levels persisted into mid-childhood
International Veterinary Epilepsy Task Force Consensus Proposal: Diagnostic approach to epilepsy in dogs
This article outlines the consensus proposal on diagnosis of epilepsy in dogs by the International Veterinary Epilepsy Task Force. The aim of this consensus proposal is to improve consistency in the diagnosis of epilepsy in the clinical and research settings. The diagnostic approach to the patient presenting with a history of suspected epileptic seizures incorporates two fundamental steps: to establish if the events the animal is demonstrating truly represent epileptic seizures and if so, to identify their underlying cause. Differentiation of epileptic seizures from other non-epileptic episodic paroxysmal events can be challenging. Criteria that can be used to make this differentiation are presented in detail and discussed. Criteria for the diagnosis of idiopathic epilepsy (IE) are described in a three-tier system. Tier I confidence level for the diagnosis of IE is based on a history of two or more unprovoked epileptic seizures occurring at least 24 h apart, age at epileptic seizure onset of between six months and six years, unremarkable inter-ictal physical and neurological examination, and no significant abnormalities on minimum data base blood tests and urinalysis. Tier II confidence level for the diagnosis of IE is based on the factors listed in tier I and unremarkable fasting and post-prandial bile acids, magnetic resonance imaging (MRI) of the brain (based on an epilepsy-specific brain MRI protocol) and cerebrospinal fluid (CSF) analysis. Tier III confidence level for the diagnosis of IE is based on the factors listed in tier I and II and identification of electroencephalographic abnormalities characteristic for seizure disorders. The authors recommend performing MRI of the brain and routine CSF analysis, after exclusion of reactive seizures, in dogs with age at epileptic seizure onset 6 years, inter-ictal neurological abnormalities consistent with intracranial neurolocalisation, status epilepticus or cluster seizure at epileptic seizure onset, or a previous presumptive diagnosis of IE and drug-resistance with a single antiepileptic drug titrated to the highest tolerable dose
The Deconfinement Phase Transition in One-Flavour QCD
We present a study of the deconfinement phase transition of one-flavour QCD,
using the multiboson algorithm. The mass of the Wilson fermions relevant for
this study is moderately large and the non-hermitian multiboson method is a
superior simulation algorithm. Finite size scaling is studied on lattices of
size , and . The behaviours of the
peak of the Polyakov loop susceptibility, the deconfinement ratio and the
distribution of the norm of the Polyakov loop are all characteristic of a
first-order phase transition for heavy quarks. As the quark mass decreases, the
first-order transition gets weaker and turns into a crossover. To investigate
finite size scaling on larger spatial lattices we use an effective action in
the same universality class as QCD. This effective action is constructed by
replacing the fermionic determinant with the Polyakov loop identified as the
most relevant Z(3) symmetry breaking term. Higher-order effects are
incorporated in an effective Z(3)-breaking field, , which couples to the
Polyakov loop. Finite size scaling determines the value of where the first
order transition ends. Our analysis at the end - point, , indicates
that the effective model and thus QCD is consistent with the universality class
of the three dimensional Ising model.
Matching the field strength at the end point, , to the
values used in the dynamical quark simulations we estimate the end point,
, of the first-order phase transition. We find which corresponds to a quark mass of about 1.4 GeV .Comment: LaTex, 25 pages, 18 figure
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