2,801 research outputs found
Reactive and inhibiting species in the electrocatalytic oxidation of glycerol on gold : A study combining in-situ visible reflectance and ATR-SEIRAS
Acknowledgements: The support of the Leverhulme Trust through the Doctoral Scholarship Scheme [DS-2017-073] is gratefully acknowledged.Peer reviewedPostprin
Arcus Mission Design: Stable Lunar-Resonant High Earth Orbit for X-Ray Astronomy
The Arcus mission, proposed for NASA's 2016 Astrophysics Medium Explorer (MIDEX) announcement of opportunity, will use X-ray spectroscopy to detect previously unaccounted quantities of normal matter in the Universe. The Arcus mission design uses 4:1 lunar resonance to provide a stable orbit for visibility of widely-dispersed targets, in a low background radiation environment, above the Van Allen belts for the minimum two-year science mission. Additional ad-vantages of 4:1 resonance are long term stability without maintenance maneu-vers, eclipses under 4.5 hours, perigee radius approximately 12 Re for data download, and streamlined operational cadence with approximately 1 week orbit period
Arcus Mission Design: Stable Lunar Resonant HEO for X-ray Astronomy
The Arcus mission, proposed for NASA's 2016 Astrophysics Medium Explorer (MIDEX) announcement of opportunity, will use X-ray spectroscopy to detect previously unaccounted quantities of normal matter in the Universe. The Arcus mission design uses 4:1 lunar resonance to provide a stable orbit for visibility of widely-dispersed targets, in a low background radiation environment, above the Van Allen belts for the minimum two-year science mission. Additional ad-vantages of 4:1 resonance are long term stability without maintenance maneuvers, eclipses under 4.5 hours, perigee radius approximately 12 Re for data download, and streamlined operational cadence with approximately 1 week or-bit period
A Pharmacology-Based Enrichment Program for Undergraduates Promotes Interest in Science
There is a strong need to increase the number of undergraduate students who pursue careers in science to provide the “fuel” that will power a science and technology–driven U.S. economy. Prior research suggests that both evidence-based teaching methods and early undergraduate research experiences may help to increase retention rates in the sciences. In this study, we examined the effect of a program that included 1) a Summer enrichment 2-wk minicourse and 2) an authentic Fall research course, both of which were designed specifically to support students\u27 science motivation. Undergraduates who participated in the pharmacology-based enrichment program significantly improved their knowledge of basic biology and chemistry concepts; reported high levels of science motivation; and were likely to major in a biological, chemical, or biomedical field. Additionally, program participants who decided to major in biology or chemistry were significantly more likely to choose a pharmacology concentration than those majoring in biology or chemistry who did not participate in the enrichment program. Thus, by supporting students\u27 science motivation, we can increase the number of students who are interested in science and science careers
Repairing the Leaky Pipeline: A Motivationally Supportive Intervention to Enhance Persistence in Undergraduate Science Pathways
The current study reports on the efficacy of a multi-faceted motivationally designed undergraduate enrichment summer program for supporting science, technology, engineering and math (STEM) persistence. Structural equation modeling was used to compare summer program participants (n = 186), who participated in the program between their first and second years in college, to a propensity score matched comparison sample (n = 401). Participation in the summer program positively predicted science motivation (self-efficacy, task value), assessed eight months after the end of the program (second year in college). The summer enrichment program was also beneficial for science persistence variables, as evidenced by significant direct and indirect effects of the program on science course completion during students’ third year of college and students’ intentions to pursue a science research career assessed during the third year of college. In general, the program was equally beneficial for all participants, but ancillary analyses indicated added benefits with respect to task value for students with relatively lower prior science achievement during the first year of college and with respect to subsequent science course taking for males. Implications for developing effective interventions to reduce the flow of individuals out of STEM fields and for translating motivational theory into practice are discussed
Interdisciplinary Transgender Veteran Care: Development of a Core Curriculum for VHA Providers
Purpose: The Veteran\u27s Health Administration (VHA) has created a training program for interdisciplinary teams of providers on the unique treatment needs of transgender veterans. An overview of this program\u27s structure and content is described along with an evaluation of each session and the program overall. Methods: A specialty care team delivered 14 didactic courses supplemented with case consultation twice per month over the course of 7 months through video teleconferencing to 16 teams of learners. Each team, consisting of at least one mental health provider (e.g., social worker, psychologist, or psychiatrist) and one medical provider (e.g., physician, nurse, physician assistant, advanced practice nurse, or pharmacist), received training and consultation on transgender veteran care. Results: In the first three waves of learners, 111 providers across a variety of disciplines attended the sessions and received training. Didactic topics included hormone therapy initiation and adjustments, primary care issues, advocacy within the system, and psychotherapy issues. Responses were provided to 39 veteran-specific consult questions to augment learning. Learners reported an increase in knowledge plus an increase in team cohesion and functioning. As a result, learners anticipated treating more transgender veterans in the future. Conclusion: VHA providers are learning about the unique healthcare needs of transgender veterans and benefitting from the training opportunity offered through the Transgender Specialty Care Access Network-Extension of Community Healthcare Outcomes program. The success of this program in training interdisciplinary teams of providers suggests that it might serve as a model for other large healthcare systems. In addition, it provides a path forward for individual learners (both within VHA and in the community) who wish to increase their knowledge
A roadmap for global synthesis of the plant tree of life
Providing science and society with an integrated, up-to-date, high quality, open, reproducible and sustainable plant tree of life would be a huge service that is now coming within reach. However, synthesizing the growing body of DNA sequence data in the public domain and disseminating the trees to a diverse audience are often not straightforward due to numerous informatics barriers. While big synthetic plant phylogenies are being built, they remain static and become quickly outdated as new data are published and tree-building methods improve. Moreover, the body of existing phylogenetic evidence is hard to navigate and access for non-experts. We propose that our community of botanists, tree builders, and informaticians should converge on a modular framework for data integration and phylogenetic analysis, allowing easy collaboration, updating, data sourcing and flexible analyses. With support from major institutions, this pipeline should be re-run at regular intervals, storing trees and their metadata long-term. Providing the trees to a diverse global audience through user-friendly front ends and application development interfaces should also be a priority. Interactive interfaces could be used to solicit user feedback and thus improve data quality and to coordinate the generation of new data. We conclude by outlining a number of steps that we suggest the scientific community should take to achieve global phylogenetic synthesis
CEERS Key Paper VII: Emission Line Ratios from NIRSpec and NIRCam Wide-Field Slitless Spectroscopy at z>2
We use James Webb Space Telescope Near-Infrared Camera Wide Field Slitless
Spectroscopy (NIRCam WFSS) and Near-Infrared spectrograph (NIRSpec) in the
Cosmic Evolution Early Release survey (CEERS) to measure rest-frame optical
emission-line of 155 galaxies at z>2. The blind NIRCam grism observations
include a sample of galaxies with bright emission lines that were not observed
on the NIRSpec masks. We study the changes of the Ha, [OIII]/Hb, and
[NeIII]/[OII] emission lines in terms of redshift by comparing to lower
redshift SDSS and CLEAR samples. We find a significant (>3) correlation
between [OIII]/Hb with redshift, while [NeIII]/[OII] has a marginal (2)
correlation with redshift. We compare [OIII]/Hb and [NeIII]/[OII] to stellar
mass and Hb SFR. We find that both emission-line ratios have a correlation with
Hb SFR and an anti-correlation with stellar mass across the redshifts 0<z<9.
Comparison with MAPPINGS~V models indicates that these trends are consistent
with lower metallicity and higher ionization in low-mass and high-SFR galaxies.
We additionally compare to IllustriousTNG predictions and find that they
effectively describe the highest [OIII]/Hb ratios observed in our sample,
without the need to invoke MAPPINGS models with significant shock ionizionation
components.Comment: 16 pages, 11 figure
The VLA/ALMA Nascent Disk and Multiplicity (VANDAM) Survey of Orion Protostars. I. Identifying and Characterizing the Protostellar Content of the OMC-2 FIR4 and OMC-2 FIR3 Regions
We present ALMA (0.87~mm) and VLA (9~mm) observations toward OMC2-FIR4 and
OMC2-FIR3 within the Orion integral-shaped filament that are thought to be the
nearest regions of intermediate mass star formation. We characterize the
continuum sources within these regions on 40~AU (0\farcs1) scales and
associated molecular line emission at a factor of 30 better resolution
than previous observations at similar wavelengths. We identify six compact
continuum sources within OMC2-FIR4, four in OMC2-FIR3, and one additional
source just outside OMC2-FIR4. This continuum emission is tracing the inner
envelope and/or disk emission on less than 100~AU scales. HOPS-108 is the only
protostar in OMC2-FIR4 that exhibits emission from high-excitation transitions
of complex organic molecules (e.g., methanol and other lines) coincident with
the continuum emission. HOPS-370 in OMC2-FIR3 with L~~360~\lsun, also
exhibits emission from high-excitation methanol and other lines. The methanol
emission toward these two protostars is indicative of temperatures high enough
to thermally evaporate methanol from icy dust grains; overall these protostars
have characteristics similar to hot corinos. We do not identify a clear outflow
from HOPS-108 in \twco, but find evidence of interaction between the
outflow/jet from HOPS-370 and the OMC2-FIR4 region. The multitude of
observational constraints indicate that HOPS-108 is likely a low to
intermediate-mass protostar in its main mass accretion phase and it is the most
luminous protostar in OMC2-FIR4. The high resolution data presented here are
essential for disentangling the embedded protostars from their surrounding
dusty environments and characterizing them
Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.
Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis
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