The First Five Minutes: Enhancing Simulation Education for First-Year Pediatric Residents

We are looking at the feasibility of redesigning the existing simulation education for first-year residents within the Children’s Hospital of Richmond at VCU’s pediatric residency program to increase learning opportunities and to enhance exposure to pediatric medical emergencies. Novel simulation scenarios were designed to provide an introduction to managing the first five minutes of commonly encountered emergencies on the inpatient wards. These shortened simulations allow for educational objectives to be tailored to the expected knowledge and responsibilities of first-year residents

Not In Our Backyard: Spectroscopic Support for the CLASH z=11 Candidate MACS0647-JD

We report on our first set of spectroscopic Hubble Space Telescope observations of the z~11 candidate galaxy strongly lensed by the MACSJ0647.7+7015 galaxy cluster. The three lensed images are faint and we show that these early slitless grism observations are of sufficient depth to investigate whether this high-redshift candidate, identified by its strong photometric break at ~1.5 micron, could possibly be an emission line galaxy at a much lower redshift. While such an interloper would imply the existence of a rather peculiar object, we show here that such strong emission lines would clearly have been detected. Comparing realistic, two-dimensional simulations to these new observations we would expect the necessary emission lines to be detected at >5 sigma while we see no evidence for such lines in the dispersed data of any of the three lensed images. We therefore exclude that this object could be a low redshift emission line interloper, which significantly increases the likelihood of this candidate being a bona fide z~11 galaxy.Comment: 14 Pages. 6 Figures. 2nd revised version. Accepted. To appear in ApJ. Please contact [email protected] for comments on this pape

Bedrock Erosion by Debris Flows at Chalk Cliffs, Colorado, USA: Implications for Bedrock Channel Evolution

Debris flow erosion into bedrock helps to set the pace of mountain denudation, but there are few empirical observations of this process. We studied the effects of debris flows on bedrock erosion using Structure-From-Motion photogrammetry and multiple real-time monitoring measurements. We found that the distribution of bedrock erosion across the channel cross-section could be generalized as an exponentially decreasing function of height above the channel thalweg. Using this empirical function, we simulated the erosion at a cross-section after the theoretical passage of a migrating knickpoint effectively matching the upstream pre-knickpoint cross-sectional shape to the downstream post-knickpoint cross-sectional shape via debris-flow bedrock erosion

Expanding First Generation Student Support Services at VCU

This project aims to increase first-generation student outcomes by taking existing YouFirst programming to scale. The team proposes to expand university outreach and to leverage expanded engagement into the construction of a First Gen Network through a university-wide ambassador program. This network will grow programming over the next three to five years through annual faculty and staff outreach and the creation of a pipeline for cross-unit communication and collaboration

The Safe and Efficient Development of Offshore Transboundary Hydrocarbons: Best Practices from the North Sea and Their Application to the Gulf of Mexico

Offshore hydrocarbon resources have been developed for many decades, and with technology improvements, many fields which were once impossible to develop, are now economically and technologically feasible. This has led to a growing difficulty in determining the legislative and regulatory framework for resources that straddle the recognized borders between two states. In this paper, we examine a successful framework agreement governing the transboundary resources between the United Kingdom (“U.K.”) and Norway in the North Sea, and the agreement between the United States and Mexico governing the Gulf of Mexico. Following the 2013 Energy Reform, the Mexican energy sector has been revitalized, leading to greater exploration, development, and production than ever before. This means that in the near future transboundary resources may be licensed for production, bringing the issues highlighted in this paper to the attention of multiple government and international entities. This paper seeks to recommend improvements to the transboundary framework in the Gulf of Mexico based on the successful framework agreement utilized in the North Sea. This paper begins by introducing international law for offshore resources in Part II. Part III discusses the offshore regulatory regimes in the U.K. and Norway, analyzing how the two states have successfully used bilateral agreements to facilitate cooperation regarding effective exploitation and apportionment of costs from cross-boundary offshore oil and gas projects in the North Sea. Part IV discusses the offshore regulatory regimes in the United States and Mexico and analyzes the current transboundary agreement in place for the Gulf of Mexico. Part V compares the transboundary agreement governing the North Sea and the same governing the Gulf of Mexico. We highlight the major differences in the agreements and suggest changes to the Gulf of Mexico agreement based on the successful North Sea agreement. Finally, this paper concludes and provides key policy recommendations to improve the rules and regulations surrounding the exploitation of transboundary hydrocarbons in the Gulf of Mexico

Validation of ethnicity in administrative hospital data in women giving birth in England: cohort study.

OBJECTIVE: To describe the accuracy of coding of ethnicity in National Health Service (NHS) administrative hospital records compared with self-declared records in maternity booking systems, and to assess the potential impact of misclassification bias. DESIGN: Secondary analysis of data from records of women giving birth in England (2015-2017). SETTING: NHS Trusts in England participating in a national audit programme. PARTICIPANTS: 1 237 213 women who gave birth between 1 April 2015 and 31 March 2017. PRIMARY AND SECONDARY OUTCOME MEASURES: (1) Proportion of women with complete ethnicity; (2) agreement on coded ethnicity between maternity (maternity information systems (MIS)) and administrative hospital (Hospital Episode Statistics (HES)) records; (3) rates of caesarean section and obstetric anal sphincter injury by ethnic group in MIS and HES. RESULTS: 91.3% of women had complete information regarding ethnicity in HES. Overall agreement between data sets was 90.4% (κ=0.83); 94.4% when collapsed into aggregate groups of white/South Asian/black/mixed/other (κ=0.86). Most disagreement was seen in women coded as mixed in either data set. Rates of obstetrical events and complications by ethnicity were similar regardless of data set used, with the most differences seen in women coded as mixed. CONCLUSIONS: Levels of accuracy in ethnicity coding in administrative hospital records support the use of ethnicity collapsed into groups (white/South Asian/black/mixed/other), but findings for mixed and other groups, and more granular classifications, should be treated with caution. Robustness of results of analyses for associations with ethnicity can be improved by using additional primary data sources

CLASH: Extreme Emission Line Galaxies and Their Implication on Selection of High-Redshift Galaxies

We utilize the CLASH (Cluster Lensing And Supernova survey with Hubble) observations of 25 clusters to search for extreme emission-line galaxies (EELGs). The selections are carried out in two central bands: F105W (Y105) and F125W (J125), as the flux of the central bands could be enhanced by the presence of [O III] 4959, 5007 at redshift of about 0.93-1.14 and 1.57-1.79, respectively. The multi-band observations help to constrain the equivalent widths of emission lines. Thanks to cluster lensing, we are able to identify 52 candidates down to an intrinsic limiting magnitude of 28.5 and to a rest-frame [O III] 4959,5007 equivalent width of about 3737 angstrom. Our samples include a number of EELGs at lower luminosities that are missed in other surveys, and the extremely high equivalent width can be only found in such faint galaxies. These EELGs can mimic the dropout feature similar to that of high redshift galaxies and contaminate the color-color selection of high redshift galaxies when the S/N ratio is limited or the band coverage is incomplete. We predict that the fraction of EELGs in the future high redshift galaxy selections cannot be neglected.Comment: 17 pages, 9 figures, 2 tables, Accepted for publication in AP

Hubble Space Telescope Combined Strong and Weak Lensing Analysis of the CLASH Sample: Mass and Magnification Models and Systematic Uncertainties

We present results from a comprehensive lensing analysis in HST data, of the complete CLASH cluster sample. We identify new multiple-images previously undiscovered allowing improved or first constraints on the cluster inner mass distributions and profiles. We combine these strong-lensing constraints with weak-lensing shape measurements within the HST FOV to jointly constrain the mass distributions. The analysis is performed in two different common parameterizations (one adopts light-traces-mass for both galaxies and dark matter while the other adopts an analytical, elliptical NFW form for the dark matter), to provide a better assessment of the underlying systematics - which is most important for deep, cluster-lensing surveys, especially when studying magnified high-redshift objects. We find that the typical (median), relative systematic differences throughout the central FOV are $\sim40\%$ in the (dimensionless) mass density, $\kappa$, and $\sim20\%$ in the magnification, $\mu$. We show maps of these differences for each cluster, as well as the mass distributions, critical curves, and 2D integrated mass profiles. For the Einstein radii ($z_{s}=2$) we find that all typically agree within $10\%$ between the two models, and Einstein masses agree, typically, within $\sim15\%$. At larger radii, the total projected, 2D integrated mass profiles of the two models, within r\sim2\arcmin, differ by $\sim30\%$. Stacking the surface-density profiles of the sample from the two methods together, we obtain an average slope of $d\log (\Sigma)/d\log(r)\sim-0.64\pm0.1$, in the radial range [5,350] kpc. Lastly, we also characterize the behavior of the average magnification, surface density, and shear differences between the two models, as a function of both the radius from the center, and the best-fit values of these quantities.Comment: 35 pages (20 main text pages, plus 15 pages for additional figures and tables); 2 Tables, 17 Figures. V3: accepted version; some minor corrections and additions made. V4: corrected several entries in Table 2. All mass models and magnification maps are made publicly available for the communit

CLASH-X: A Comparison of Lensing and X-ray Techniques for Measuring the Mass Profiles of Galaxy Clusters

We present profiles of temperature (Tx), gas mass, and hydrostatic mass estimated from new and archival X-ray observations of CLASH clusters. We compare measurements derived from XMM and Chandra observations with one another and compare both to gravitational lensing mass profiles derived with CLASH HST and ground-based lensing data. Radial profiles of Chandra and XMM electron density and enclosed gas mass are nearly identical, indicating that differences in hydrostatic masses inferred from X-ray observations arise from differences in Tx measurements. Encouragingly, cluster Txs are consistent with one another at ~100-200 kpc radii but XMM Tx systematically decline relative to Chandra Tx at larger radii. The angular dependence of the discrepancy suggests additional investigation on systematics such as the XMM point spread function correction, vignetting and off-axis responses. We present the CLASH-X mass-profile comparisons in the form of cosmology-independent and redshift-independent circular-velocity profiles. Ratios of Chandra HSE mass profiles to CLASH lensing profiles show no obvious radial dependence in the 0.3-0.8 Mpc range. However, the mean mass biases inferred from the WL and SaWLens data are different. e.g., the weighted-mean value at 0.5 Mpc is = 0.12 for the WL comparison and = -0.11 for the SaWLens comparison. The ratios of XMM HSE mass profiles to CLASH lensing profiles show a pronounced radial dependence in the 0.3-1.0 Mpc range, with a weighted mean mass bias of value rising to ~0.3 at ~1 Mpc for the WL comparison and of 0.25 for SaWLens comparison. The enclosed gas mass profiles from both Chandra and XMM rise to a value 1/8 times the total-mass profiles inferred from lensing at 0.5 Mpc and remain constant outside of that radius, suggesting that [8xMgas] profiles may be an excellent proxy for total-mass profiles at >0.5 Mpc in massive galaxy clusters.Comment: Accepted to ApJ; 24 pages; scheduled to appear in the Oct 10, 2014 issue. This version corrects the typographical error in the superscripts for Equation (2) to include the square of (r/r_core). The correct version of this equation was used in the analysi