112 research outputs found
Clathrin Heavy Chain subunits coordinate endo- and exocytic traffic and affect stomatal movement
The current model for vesicular traffic to and from the plasma membrane is accepted but the molecular requirements for this coordination are not well defined. We have identified the has1 mutant, which has a stomatal function defect, as a clathrin heavy chain 1 (CHC1) mutant allele and show that it has a decreased rate of endocytosis and growth defects that are shared with other chc1 mutant alleles. We used chc1 alleles and the related chc2 mutant as tools to investigate the effects clathrin defects have on secretion pathways and plant growth. We show that secretion and endocytosis at the plasma membrane is sensitive to CHC1 and CHC2 function in seedling roots, and that chc mutants have physiological defects in stomatal function and plant growth that have not been previously described. These findings suggest that clathrin supports specific functions of multiple cell types. Stomata movement and gas exchange is altered in chc mutants, indicating clathrin is important for stomatal regulation. The aberrant function of chc mutant stomata is consistent with the growth phenotypes observed under different water and light conditions, which are also similar to those of the secretory SNARE mutant, syp121. The syp121 and chc mutants have impaired endo- and exocytosis compared to wild type, indicating a link between SYP121-dependent secretion and clathrin-dependent endocytosis at the plasma membrane. Our findings provide evidence that clathrin and SYP121 functions are important for the coordination of endo- and exocytosis, and have an impact on stomatal function, gas exchange, and vegetative growth in Arabidopsis
Using Fad Diets to Teach Information Evaluation
In Spring 2021, the librarian presenters partnered with Laura Bauer, a Nutrition faculty member, to teach students in introductory Nutrition classes information evaluation skills. The instructor\u27s assignment originally asked the class of non-science major students to find a recipe online that met a personal nutrition goal based on current recommendations. The assignment evolved for a class of pre-health science students into an evaluative assignment where students were asked to research a fad diet online and compare those findings with the scholarly literature, all while considering diet culture through a social justice lens. In this session we\u27ll discuss how the librarians and professor collaborated to create an assignment that incorporated the learning objectives of the course into a real-life scenario where students would be expected to critically evaluate information. Over our two-part library instruction session with the pre-health science majors, we introduced two evaluation methods to students in the class: SIFT (Stop, Investigate the source, Find trusted coverage, Trace the claims) and TRAP (Timeliness, Relevance, Authority, Purpose). We will explain these evaluation techniques and how they can be applied to evaluate various types of information. We will also discuss our plans to incorporate the fad diet assignment into courses for non-science majors in the fall, replacing the more basic recipe assignment
Spatio-temporal dynamics of wormlike micelles under shear
Velocity profiles in a wormlike micelle solution (CTAB in D2O) are recorded
using ultrasound every 2 s after a step-like shear rate into the shear-banding
regime. The stress relaxation occurs over more than six hours and corresponds
to the very slow nucleation and growth of the high-shear band. Moreover,
oscillations of the interface position with a period of about 50 s are observed
during the growth process. Strong wall slip, metastable states and transient
nucleation of three-band flows are also reported and discussed in light of
previous experiments and theoretical models.Comment: 4 pages, 5 figures, submitted to Phys.Rev.Let
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Health Service Utilization among Medicaid Enrollees in Oregon : Assessing Variation by Level of Rurality
Research Objective: Nearly 60 million people in the United States reside in a rural area. Residents in rural areas have higher rates of chronic disease, risky health behaviors, disability, infant mortality, and age-adjusted mortality than their urban counterparts. Health insurance and access to care mitigate those risks, in part because insured persons are more likely to receive preventive care. Before implementation of the Affordable Care Act (ACA), 16% of the US population was uninsured. By 2016 the uninsured rate dropped to 10.5%. Many of those obtained coverage through state Medicaid expansion. It is important to understand how those newly enrolled in Medicaid are utilizing care, especially in more rural parts of the US where access may be more challenging. This study examined whether there were differences across levels of rurality in preventive and behavioral health service utilization among new expansion enrollees in Oregon compared to those previously enrolled. Study Design: This study used a quasi-experimental, retrospective cohort design utilizing: Oregon Medicaid claims and eligibility, as well as Rural Urban Commuting Areas (RUCAs), American Community Survey, and Health Resources and Services Administration Primary Care Service Area data. Linear probability models were used to estimate the effect of rurality on preventive and behavioral health service utilization among new versus previous Medicaid enrollees. Additionally, this study examined the effects of continuity of coverage on health service utilization by level of rurality among those newly enrolled and previous enrollees. Models controlled for age, sex, race, ethnicity, eligibility category, chronic conditions, and enrollment in a Medicaid accountable care organization (Coordinated Vare Organization or CCO) as well as the number of primary care providers per population, and median home value
Velocity profiles in shear-banding wormlike micelles
Using Dynamic Light Scattering in heterodyne mode, we measure velocity
profiles in a much studied system of wormlike micelles (CPCl/NaSal) known to
exhibit both shear-banding and stress plateau behavior. Our data provide
evidence for the simplest shear-banding scenario, according to which the
effective viscosity drop in the system is due to the nucleation and growth of a
highly sheared band in the gap, whose thickness linearly increases with the
imposed shear rate. We discuss various details of the velocity profiles in all
the regions of the flow curve and emphasize on the complex, non-Newtonian
nature of the flow in the highly sheared band.Comment: 4 pages, 5 figures, submitted to Phys. Rev. Let
The Thermal Regulation of Gravitational Instabilities in Protoplanetary Disks II. Extended Simulations with Varied Cooling Rates
In order to investigate mass transport and planet formation by gravitational
instabilities (GIs), we have extended our 3-D hydrodynamic simulations of
protoplanetary disks from a previous paper. Our goal is to determine the
asymptotic behavior of GIs and how it is affected by different constant cooling
times. Initially, Rdisk = 40 AU, Mdisk = 0.07 Mo, M* = 0.5 Mo, and Qmin = 1.8.
Sustained cooling, with tcool = 2 orps (outer rotation periods, 1 orp ~ 250
yrs), drives the disk to instability in ~ 4 orps. This calculation is followed
for 23.5 orps. After 12 orps, the disk settles into a quasi-steady state with
sustained nonlinear instabilities, an average Q = 1.44 over the outer disk, a
well-defined power-law Sigma(r), and a roughly steady Mdot ~ 5(-7) Mo/yr. The
transport is driven by global low-order spiral modes. We restart the
calculation at 11.2 orps with tcool = 1 and 1/4 orp. The latter case is also
run at high azimuthal resolution. We find that shorter cooling times lead to
increased Mdots, denser and thinner spiral structures, and more violent dynamic
behavior. The asymptotic total internal energy and the azimuthally averaged
Q(r) are insensitive to tcool. Fragmentation occurs only in the high-resolution
tcool = 1/4 orp case; however, none of the fragments survive for even a quarter
of an orbit. Ring-like density enhancements appear and grow near the boundary
between GI active and inactive regions. We discuss the possible implications of
these rings for gas giant planet formation.Comment: Due to document size restrictions, the complete manuscript could not
be posted on astroph. Please go to http://westworld.astro.indiana.edu to
download the full document including figure
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Analyzing the current state of Oregon's skilled nursing facilities
The purpose of this project is to paint a picture of the state of Oregon’s Skilled Nursing Facilities for the 2015 state fiscal year. Skilled Nursing Facilities are an important part of Oregon’s Long Term care continuum that provides care to individuals needing post-acute or on-going care. The URAP student assisted Public Health faculty and PhD students in preparing a report for the Oregon Department of Human Services. The student extracted, managed, summarized, and performed quality control on data from Skilled Nursing Facility Cost Reports and Revenue Statements. This data was further analyzed by the PhD students. The student also created graphs and tables of these data as well as other data from the Skilled Nursing Facility Minimum Data Set (MDS). The student performed new analyses of quality measure data retrieved though Nursing Home Compare, which is managed by the Center for Medicare and Medicaid services (CMS). These analyses described the variation in performance across Oregon Skilled Nursing Facilities. For example, moderate to severe pain reported in short stays was 11% in the highest performing 25% of all facilities and 42% in the lowest performing 25% of facilities, which highlights differences between the highest and lowest performing facilities
Participatory Sustainability Approach to Value Capture-Based Urban Rail Financing in India through Deliberated Stakeholder Engagement
Increasingly, cities around the world are seeking innovative financial mechanisms to build rail transit projects. Land value capture (VC) is a financing mechanism to fund urban rail transit. Often VC mechanisms are viewed only as a financing tool applied in relation to increased land values from the administration and legislation perspectives, without actively involving the community in the process. The lack of such participation has resulted in the under collection of the true value established. The transit beneficiary community and city tax payers are especially important stakeholders in this process as their willingness to participate is really critical to the overall VC success and transport outcome. This paper introduces a participatory sustainability approach to enable a more deliberated stakeholder engagement intervention across the VC life cycle. A four-step “Participatory Strategic Value Capture (PSVC)” framework is proposed offering step-by-step guidance toward facilitating a meaningful stakeholder dialogue, deliberation, and collaboration around the stated engagement interests. The PSVC framework, applied to the proposed Bangalore sub-urban rail project in India, has demonstrated the importance of stakeholder engagement using deliberated participatory approaches from a win-win perspective
The Magellanic Mopra Assessment (MAGMA). I. The Molecular Cloud Population of the Large Magellanic Cloud
We present the properties of an extensive sample of molecular clouds in the
Large Magellanic Cloud (LMC) mapped at 11 pc resolution in the CO(1-0) line. We
identify clouds as regions of connected CO emission, and find that the
distributions of cloud sizes, fluxes and masses are sensitive to the choice of
decomposition parameters. In all cases, however, the luminosity function of CO
clouds is steeper than dN/dL \propto L^{-2}, suggesting that a substantial
fraction of mass is in low-mass clouds. A correlation between size and
linewidth, while apparent for the largest emission structures, breaks down when
those structures are decomposed into smaller structures. We argue that the
correlation between virial mass and CO luminosity is the result of comparing
two covariant quantities, with the correlation appearing tighter on larger
scales where a size-linewidth relation holds. The virial parameter (the ratio
of a cloud's kinetic to self-gravitational energy) shows a wide range of values
and exhibits no clear trends with the CO luminosity or the likelihood of
hosting young stellar object (YSO) candidates, casting further doubt on the
assumption of virialization for molecular clouds in the LMC. Higher CO
luminosity increases the likelihood of a cloud harboring a YSO candidate, and
more luminous YSOs are more likely to be coincident with detectable CO
emission, confirming the close link between giant molecular clouds and massive
star formation.Comment: Accepted by ApJS; 22 pages in emulateapj format; full-resolution
version and data tables available at http://mmwave.astro.illinois.edu/magma
PHANGS-JWST First Results: Dust embedded star clusters in NGC 7496 selected via 3.3 m PAH emission
The earliest stages of star formation occur enshrouded in dust and are not
observable in the optical. Here we leverage the extraordinary new
high-resolution infrared imaging from JWST to begin the study of dust-embedded
star clusters in nearby galaxies throughout the local volume. We present a
technique for identifying dust-embedded clusters in NGC 7496 (18.7 Mpc), the
first galaxy to be observed by the PHANGS-JWST Cycle 1 Treasury Survey. We
select sources that have strong 3.3m PAH emission based on a color excess, and identify 67 candidate embedded clusters. Only
eight of these are found in the PHANGS-HST optically-selected cluster catalog
and all are young (six have SED-fit ages of Myr). We find that this
sample of embedded cluster candidates may significantly increase the census of
young clusters in NGC 7496 from the PHANGS-HST catalog -- the number of
clusters younger than 2 Myr could be increased by a factor of two.
Candidates are preferentially located in dust lanes, and are coincident with
peaks in PHANGS-ALMA CO (2-1) maps. We take a first look at concentration
indices, luminosity functions, SEDs spanning from 2700A to 21m, and
stellar masses (estimated to be between ). The methods
tested here provide a basis for future work to derive accurate constraints on
the physical properties of embedded clusters, characterize the completeness of
cluster samples, and expand analysis to all 19 galaxies in the PHANGS-JWST
sample, which will enable basic unsolved problems in star formation and cluster
evolution to be addressed.Comment: 12 pages, 6 figures; accepted for publication in ApJL as part of
PHANGS-JWST First Results Special Issu
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