485 research outputs found
From Opportunity to Necessity: Development of an Asynchronous Online Interprofessional Learning Experience
Incorporating interprofessional collaboration competencies into both undergraduate pre-licensure and graduate health science students poses challenges for academic health science centers. Certain student groups may have less opportunity to participate in interprofessional learning experiences due to demands of individual programs of study and conflicts in scheduling time with other disciplines. A group of interprofessional higher education faculty members created an innovative online asynchronous interprofessional experience with the primary goals of meeting accreditation standards for specific programs and providing interprofessional education (IPE) to students who were unable to participate in traditional face-to-face IPE experiences already established at the institution. This guide will highlight the process of design and development of the learning opportunity, from conception to implementation. The pilot of the asynchronous online IPE experience served as a model for the transition of the original in-person model to virtual IPE during the COVID-19 pandemic
Upper extremity freezing and dyscoordination in Parkinson\u27s disease: Effects of amplitude and cadence manipulations
Purpose. Motor freezing, the inability to produce effective movement, is associated with decreasing amplitude, hastening of movement, and poor coordination. We investigated how manipulations of movement amplitude and cadence affect upper extremity (UE) coordination as measured by the phase coordination index (PCI)—only previously measured in gait—and freezing of the upper extremity (FO-UE) in people with Parkinson's disease (PD) who experience freezing of gait (PD + FOG), do not experience FOG (PD-FOG), and healthy controls. Methods. Twenty-seven participants with PD and 18 healthy older adults made alternating bimanual movements between targets under four conditions: Baseline; Fast; Small; SmallFast. Kinematic data were recorded and analyzed for PCI and FO-UE events. PCI and FO-UE were compared across groups and conditions. Correlations between UE PCI, gait PCI, FO-UE, and Freezing of Gait Questionnaire (FOG-Q) were determined. Results. PD + FOG had poorer coordination than healthy old during SmallFast. UE coordination correlated with number of FO-UE episodes in two conditions and FOG-Q score in one. No differences existed between PD−/+FOG in coordination or number of FO-UE episodes. Conclusions. Dyscoordination and FO-UE can be elicited by manipulating cadence and amplitude of an alternating bimanual task. It remains unclear whether FO-UE and FOG share common mechanisms
A Deep XMM-Newton Survey of M33: Point Source Catalog, Source Detection and Characterization of Overlapping Fields
We have obtained a deep 8-field XMM-Newton mosaic of M33 covering the galaxy
out to the D isophote and beyond to a limiting 0.2--4.5 keV unabsorbed
flux of 510 erg cm s (L410
erg s at the distance of M33). These data allow complete coverage of the
galaxy with high sensitivity to soft sources such as diffuse hot gas and
supernova remnants. Here we describe the methods we used to identify and
characterize 1296 point sources in the 8 fields. We compare our resulting
source catalog to the literature, note variable sources, construct hardness
ratios, classify soft sources, analyze the source density profile, and measure
the X-ray luminosity function. As a result of the large effective area of
XMM-Newton below 1 keV, the survey contains many new soft X-ray sources. The
radial source density profile and X-ray luminosity function for the sources
suggests that only 15% of the 391 bright sources with
L3.610 erg s are likely to be associated with M33,
and more than a third of these are known supernova remnants. The log(N)--log(S)
distribution, when corrected for background contamination, is a relatively flat
power-law with a differential index of 1.5, which suggests many of the other
M33 sources may be high-mass X-ray binaries. Finally, we note the discovery of
an interesting new transient X-ray source, which we are unable to classify.Comment: 26 pages, 6 tables, 13 figures, accepted for publication in ApJ
High-fidelity conformation of graphene to SiO2 topographic features
Strain engineering of graphene through interaction with a patterned substrate
offers the possibility of tailoring its electronic properties, but will require
detailed understanding of how graphene's morphology is determined by the
underlying substrate. However, previous experimental reports have drawn
conflicting conclusions about the structure of graphene on SiO2. Here we show
that high-resolution non-contact atomic force microscopy of SiO2 reveals
roughness at the few-nm length scale unresolved in previous measurements, and
scanning tunneling microscopy of graphene on SiO2 shows it to be slightly
smoother than the supporting SiO2 substrate. Quantitative analysis of the
competition between bending rigidity of the graphene and adhesion to the
substrate explains the observed roughness of monolayer graphene on SiO2 as
extrinsic, and provides a natural, intuitive description in terms of highly
conformal adhesion. The analysis indicates that graphene adopts the
conformation of the underlying substrate down to the smallest features with
nearly 99% fidelity.Comment: 13 pages, 3 figures plus supplemental informatio
Identifying the molecular systems that influence cognitive resilience to Alzheimer\u27s disease in genetically diverse mice.
Individual differences in cognitive decline during normal aging and Alzheimer\u27s disease (AD) are common, but the molecular mechanisms underlying these distinct outcomes are not fully understood. We utilized a combination of genetic, molecular, and behavioral data from a mouse population designed to model human variation in cognitive outcomes to search for the molecular mechanisms behind this population-wide variation. Specifically, we used a systems genetics approach to relate gene expression to cognitive outcomes during AD and normal aging. Statistical causal-inference Bayesian modeling was used to model systematic genetic perturbations matched with cognitive data that identified astrocyte and microglia molecular networks as drivers of cognitive resilience to AD. Using genetic mapping, we identifie
High frequency temperature variability reduces the risk of coral bleaching
Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (<1 km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in predicting bleaching prevalence and had a mitigating effect, such that a 1 °C increase in daily temperature range would reduce the odds of more severe bleaching by a factor of 33. Our findings suggest that reefs with greater high-frequency temperature variability may represent particularly important opportunities to conserve coral ecosystems against the major threat posed by warming ocean temperatures
Habitable Climates: The Influence of Obliquity
Extrasolar terrestrial planets with the potential to host life might have
large obliquities or be subject to strong obliquity variations. We revisit the
habitability of oblique planets with an energy balance climate model (EBM)
allowing for dynamical transitions to ice-covered snowball states as a result
of ice-albedo feedback. Despite the great simplicity of our EBM, it captures
reasonably well the seasonal cycle of global energetic fluxes at Earth's
surface. It also performs satisfactorily against a full-physics climate model
of a highly oblique Earth-like planet, in an unusual regime of circulation
dominated by heat transport from the poles to the equator. Climates on oblique
terrestrial planets can violate global radiative balance through much of their
seasonal cycle, which limits the usefulness of simple radiative equilibrium
arguments. High obliquity planets have severe climates, with large amplitude
seasonal variations, but they are not necessarily more prone to global snowball
transitions than low obliquity planets. We find that terrestrial planets with
massive CO2 atmospheres, typically expected in the outer regions of habitable
zones, can also be subject to such dynamical snowball transitions. Some of the
snowball climates investigated for CO2-rich atmospheres experience partial
atmospheric collapse. Since long-term CO2 atmospheric build-up acts as a
climatic thermostat for habitable planets, partial CO2 collapse could limit the
habitability of such planets. A terrestrial planet's habitability may thus
depend sensitively on its short-term climatic stability.Comment: Minor changes, references added. 34 pages, 13 figures, accepted by
Ap
Recurrent Modification of a Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity
The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. In Drosophila melanogaster fruit flies, the Bric-à -brac (Bab) transcription factors control the development of a suite of sexually dimorphic traits on the posterior abdomen. Female-specific Bab expression is regulated by the dimorphic element, a CRE that possesses direct inputs from body plan (ABD-B) and sex-determination (DSX) transcription factors. Here, we find that the recurrent evolutionary modification of this CRE underlies both intraspecific and interspecific variation in female pigmentation in the melanogaster species group. By reconstructing the sequence and regulatory activity of the ancestral Drosophila melanogaster dimorphic element, we demonstrate that a handful of mutations were sufficient to create independent CRE alleles with differing activities. Moreover, intraspecific and interspecific dimorphic element evolution proceeded with little to no alterations to the known body plan and sex-determination regulatory linkages. Collectively, our findings represent an example where the paths of evolution appear biased to a specific CRE, and drastic changes in function were accompanied by deep conservation of key regulatory linkages. © 2013 Rogers et al
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