Virginia\u27s Chesapeake Bay, an Oyster Sanctuary

The Crassostrea virginica population in the Chesapeake Bay is now % of what it was during the 19th century (Kimmel et al. 2007). This decline is the result of various harmful effects such as disease, nutrient pollution, acidification, hydrological change, habitat loss and over-harvesting (Ermgassen et al. 2013). The Eastern Oyster is particularly threatened by three threats, disease, acidification, and reduced water quality. C. virginicais negatively affected by these problems but is also capable of combating and/or mitigating these injuries toward the health and biodiversity of the Chesapeake Bay. The biodiversity of the bay is directly correlated with oyster populations; as oysters provide both oyster reef habitat and water filtration service to the bay, it is an especially effective species to curb the effects climate change, namely, acidification and species loss. In order to recuperate Eastern Oyster populations in the Bay, this recommendation proposes that Virginia expand its oyster sanctuary by 9,000 acres, matching Maryland’s sanctuary expansion in 2009. These ‘no-take’ sanctuaries are intended to bolster disease resistance, combat acidification, and maintain biodiversity within the bay. The costs of sanctuary establishment are minimal to none, however, if need be, the two possible funding sources are included below. The costs of the project are subject to the stability of Eastern Oyster sanctuary populations. Funds may be used if oyster sanctuaries require restoration efforts as outlined by the 2004 Chesapeake Bay Management Plan. The economic and ecological value returned to the region by healthy oyster reefs far surpasses the restoration costs in one to five years

The Importance of Broad Emission-Line Widths in Single Epoch Black Hole Mass Estimates

Estimates of the mass of super-massive black holes (BHs) in distant active galactic nuclei (AGNs) can be obtained efficiently only through single-epoch spectra, using a combination of their broad emission-line widths and continuum luminosities. Yet the reliability and accuracy of the method, and the resulting mass estimates, M_BH, remain uncertain. A recent study by Croom using a sample of SDSS, 2QZ and 2SLAQ quasars suggests that line widths contribute little information about the BH mass in these single-epoch estimates and can be replaced by a constant value without significant loss of accuracy. In this Letter, we use a sample of nearby reverberation-mapped AGNs to show that this conclusion is not universally applicable. We use the bulge luminosity (L_Bulge) of these local objects to test how well the known M_BH - L_Bulge correlation is recovered when using randomly assigned line widths instead of the measured ones to estimate M_BH. We find that line widths provide significant information about M_BH, and that for this sample, the line width information is just as significant as that provided by the continuum luminosities. We discuss the effects of observational biases upon the analysis of Croom and suggest that the results can probably be explained as a bias of flux-limited, shallow quasar samples.Comment: 10 text pages + 4 Figures + 1 Table. Accepted for publication in ApJ Letter

The political economy of trade policy in the KORUS FTA

This is an abridged version of the winner of the best paper award at the 2011 Seoul inter-GSIS competition at the Korean Institute for International Economic Policy (KIEP). The full and original paper can be found here

Dilemmas and solutions- experiences of a national Family Medicine applied knowledge licensing test during a pandemic

ABSTRACT: Background: The unprecedented COVID-19 pandemic brought significant challenges to all of medicine, including primary care training and examinations. The MRCGP AKT is high-stakes licensing 200-item MCQ for UK trainee family physicians and is part of an assessment tripos that, up to the onset of the pandemic, included a Clinical Skills Assessment using Simulated Patients and workplace based assessment. The AKT is blueprinted onto a curriculum content specification and computer delivered three times a year at test centres across the UK. It tests the knowledge base underpinning independent general practice within the context of the UK National Health Service. We report on the challenges and dilemmas faced during the pandemic, decisions taken, and lessons learned. Rapid exam changes needed to be made, and communicated effectively to candidates, whilst maintaining standards and fairness to candidates. Summary of Work: Challenges included lockdown travel restrictions, reduced capacity, social distancing and shielding candidates being unable to leave home. The April 2020 AKT was cancelled and prioritisation measures implemented to ensure candidates at the end of their training could enter the (stressed) workforce. We engaged with a wide range of stakeholders, carefully looked at remote testing, made contingency plans prioritised for those unable to sit exams and changed exam regulations to ensure fairness to candidates. In this emergency, we delivered a previously published exam which some candidates were unaware they had sat previously, and assessed how these candidates performed. We compared cohort performance before and during the pandemic. Summary of Results: We summarise why we did not remote test, how we obtained key worker status, and adapted contingency plans. Analysis of candidates who had previously sat the same exam showed they performed less well. Despite wide-ranging changes in training and workplace experience, there was no significant difference in cohort performance overall pre-and peri-pandemic. Discussion and Conclusions: COVID-19 constraints changed trainees clinical exposure, restricted training and supervisor support. However, exam preparedness did not appear adversely affected when measured by overall pass rates. Unexpectedly, candidates who sat an identical exam did not benefit from previous exposure. Take-home Messages: Involving stakeholders in key decisions and regular communications are essential. Test security and standards were not compromised

Reverberation Mapping Results from MDM Observatory

We present results from a multi-month reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from around the world. We measure broad line region (BLR) radii and black hole masses for six objects. A velocity-resolved analysis of the H_beta response shows the presence of diverse kinematic signatures in the BLR.Comment: To appear in the Proceedings of the IAU Symposium No. 267: Co-Evolution of Central Black Holes and Galaxies, Rio de Janeiro, 200

Comprehensiveness of infant formula and bottle feeding resources: A review of information from Australian healthcare organisations.

The use of infant formula is widespread internationally. In Australia, 55% of infants receive formula before 6 months of age, with higher rates among disadvantaged communities. Infant formula use can contribute to childhood overweight and obesity, through formula composition and feeding behaviours, such as adding cereal to bottles and parental feeding style. While information abounds to promote and support breastfeeding, formula-feeding parents report a paucity of advice and support; many rely on formula packaging for information. This study systematically searched and reviewed online resources for infant formula and bottle feeding from Australian governments, health services, hospitals, and not-for-profit parenting organisations. A comprehensive search strategy located 74 current resources, mostly for parents. Researchers evaluated the resources against best practice criteria derived from Australian government and UNICEF guidelines on six topics. They assessed how comprehensively the resources addressed each topic and whether the resources provided all the information necessary for parents to understand each topic. The mean 'comprehensiveness' rating for topics across all resources was 54.36%. However, some topics were addressed more fully than others. Information on 'discussing infant formula with health workers' and on 'preparing infant formula' was more frequently accurate and comprehensive. However, there was much less comprehensive information on 'using infant formula', including amounts of formula to feed, use of bottle teats, appropriate bottle-feeding practice and responsiveness to infant satiety cues. Over half the resources were written at an acceptable reading level

An Alternative Approach To Measuring Reverberation Lags in Active Galactic Nuclei

Motivated by recent progress in the statistical modeling of quasar variability, we develop a new approach to measuring emission-line reverberation lags to estimate the size of broad-line regions (BLRs) in active galactic nuclei. Assuming that all emission-line light curves are scaled, smoothed, and displaced versions of the continuum, this alternative approach fits the light curves directly using a damped random walk model and aligns them to recover the time lag and its statistical confidence limits. We introduce the mathematical formalism of this approach and demonstrate its ability to cope with some of the problems for traditional methods, such as irregular sampling, correlated errors, and seasonal gaps. We redetermine the lags for 87 emission lines in 31 quasars and reassess the BLR size--luminosity relationship using 60 H-beta lags. We confirm the general results from the traditional cross-correlation methods, with a few exceptions. Our method, however, also supports a broad range of extensions. In particular, it can simultaneously fit multiple lines and continuum light curves which improves the lag estimate for the lines and provides estimates of the error correlations between them. Determining these correlations is of particular importance for interpreting emission-line velocity--delay maps. We can also include parameters for luminosity-dependent lags or line responses. We use this to detect the scaling of the BLR size with continuum luminosity in NGC 5548.Comment: match to the version accepted to ApJ. New code release available at http://www.astronomy.ohio-state.edu/~yingzu/spear.htm

The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability

The narrow [O III] 4959, 5007 emission-line fluxes in the spectrum of the well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this we show that the narrow line-emitting region has a radius of only 1-3 pc and is denser (n ~ 10^5 cm^{-3}) than previously supposed. The [O III] line width is consistent with virial motions at this radius given previous determinations of the black hole mass.Since the [O III] emission-line flux is usually assumed to be constant and is therefore used to calibrate spectroscopic monitoring data, the variability has ramifications for the long-term secular variations of continuum and emission-line fluxes, though it has no effect on shorter-term reverberation studies. We present corrected optical continuum and broad Hbeta emission-line light curves for the period 1988 to 2008.Comment: 11 pages, 5 figures, 6 tables. Accepted for publication in Ap