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Arlington, VA, United States

Marymount University is a coeducational, four-year Catholic university that has its main campus located in Arlington, Virginia. Marymount offers bachelor’s, master’s, and doctoral degrees in a wide range of disciplines and has a diverse and welcoming academic community with approximately 3,600 students representing approximately 40 states and 70 countries. Wikipedia.

Pecaut M.J.,University of Rochester | Mamajek E.E.,University of Rochester | Bubar E.J.,University of Rochester | Bubar E.J.,Marymount University
Astrophysical Journal | Year: 2012

We present an analysis of the ages and star formation history of the F-type stars in the Upper Scorpius (US), Upper Centaurus-Lupus (UCL), and Lower Centaurus-Crux (LCC) subgroups of Scorpius-Centaurus (Sco-Cen), the nearest OB association. Our parent sample is the kinematically selected Hipparcos sample of de Zeeuw et al., restricted to the 138 F-type members. We have obtained classification-resolution optical spectra and have also determined the spectroscopic accretion disk fraction. With Hipparcos and 2MASS photometry, we estimate the reddening and extinction for each star and place the candidate members on a theoretical H-R diagram. For each subgroup we construct empirical isochrones and compare to published evolutionary tracks. We find that (1) our empirical isochrones are consistent with the previously published age-rank of the Sco-Cen subgroups; (2) subgroups LCC and UCL appear to reach the main-sequence turn-on at spectral types ∼F4 and ∼F2, respectively. An analysis of the A-type stars shows US reaching the main sequence at about spectral type ∼A3. (3) The median ages for the pre-main-sequence members of UCL and LCC are 16Myr and 17Myr, respectively, in agreement with previous studies, however we find that (4) Upper Sco is much older than previously thought. The luminosities of the F-type stars in US are typically a factor of ∼2.5 less luminous than predicted for a 5Myr old population for four sets of evolutionary tracks. We re-examine the evolutionary state and isochronal ages for the B-, A-, and G-type Upper Sco members, as well as the evolved M supergiant Antares, and estimate a revised mean age for Upper Sco of 11 ± 1 ± 2 Myr (statistical, systematic). Using radial velocities and Hipparcos parallaxes we calculate a lower limit on the kinematic expansion age for Upper Sco of >10.5Myr (99% confidence). However, the data are statistically consistent with no expansion. We reevaluate the inferred masses for the known substellar companions in Upper Sco using the revised age and find that the inferred masses are typically ∼20%-70% higher than the original estimates which had assumed a much younger age; specifically, we estimate the mass of 1RXS J1609-2105b to be 14+2 -3 M Jup, suggesting that it is a brown dwarf rather than a planet. Finally, we find the fraction of F-type stars exhibiting Hα emission and/or a K-band excess consistent with accretion to be 0/17 (<19%; 95% CL) in US at ∼11 Myr, while UCL has 1/41 (2+5 -1%; 68% CL) accretors and LCC has 1/50 (2+4 -1%; 68% CL) accretors at ∼16 Myr and ∼17 Myr, respectively. © 2012 The American Astronomical Society. All rights reserved. Source

Barenfeld S.A.,University of Rochester | Bubar E.J.,University of Rochester | Bubar E.J.,Marymount University | Mamajek E.E.,University of Rochester | Young P.A.,Arizona State University
Astrophysical Journal | Year: 2013

The AB Dor Moving Group consists of a "nucleus" of ∼10 stars at d ≃ 20 pc, along with dozens of purported "stream" members distributed across the sky. We perform a chemical and kinematic analysis of a subsample of AB Dor stream stars to test whether they constitute a physical stellar group. We use the NEMO Galactic kinematic code to investigate the orbits of the stream members, and perform a chemical abundance analysis using high resolution spectra taken with the Magellan Clay 6.5 m telescope. Using a χ2 test with the measured abundances for 10 different elements, we find that only half of the purported AB Dor stream members could possibly constitute a statistically chemically homogeneous sample. Some stream members with three-dimensional velocities were hundreds of parsecs from the AB Dor nucleus ∼108 yr ago, and hence were unlikely to share a common origin. We conclude that the published lists of AB Dor moving group stream members are unlikely to represent the dispersed remnant of a single star formation episode. A subsample of the stream stars appears to be both statistically chemically homogeneous and in the vicinity of the AB Dor nucleus at birth. Their mean metallicity is [Fe/H] = 0.02 ± 0.02 dex, which we consider representative for the AB Dor group. Finally, we report a strong lower limit on the age of the AB Dor nucleus of >110 Myr based on the pre-main sequence contraction times for K-type members which have reached the main sequence. © 2013. The American Astronomical Society. All rights reserved.. Source

Breivik H.,University of Oslo | Eisenberg E.,Institute of Pain Medicine | O'Brien T.,Marymount University
BMC Public Health | Year: 2013

Background: Chronic pain is common in Europe and elsewhere and its under treatment confers a substantial burden on individuals, employers, healthcare systems and society in general. Indeed, the personal and socioeconomic impact of chronic pain is as great as, or greater, than that of other established healthcare priorities. In light of review of recently published data confirming its clinical and socioeconomic impact, this paper argues that chronic pain should be ranked alongside other conditions of established priority in Europe. We outline strategies to help overcome barriers to effective pain care resulting in particular from deficiencies in education and access to interdisciplinary pain management services. We also address the confusion that exists between proper clinical and scientific uses of opioid medications and their potential for misuse and diversion, as reflected in international variations in the access to, and availability of, these agents. Discussion. As the economic costs are driven in part by the costs of lost productivity, absenteeism and early retirement, pain management should aim to fully rehabilitate patients, rather than merely to relieve pain. Accredited education of physicians and allied health professionals regarding state-of-the-art pain management is crucial. Some progress has been made in this area, but further provision and incentivization is required. We support a tiered approach to pain management, whereby patients with pain uncontrolled by non-specialists are able to consult a physician with a pain competency or a specialist in pain medicine, who in turn can recruit the services of other professionals on a case-by-case basis. A fully integrated interdisciplinary pain service should ideally be available to patients with refractory pain. Governments and healthcare systems should ensure that their policies on controlled medications are balanced, safeguarding public health without undue restrictions that compromise patient care, and that physician education programmes support these aims. Summary. Strategic prioritization and co-ordinated actions are required nationally and internationally to address the unacceptable and unnecessary burden of uncontrolled chronic pain that plagues European communities and economies. An appreciation of the 'return on investment' in pain management services will require policymakers to adopt a long-term, cross-budgetary approach. © 2013 Breivik et al.; licensee BioMed Central Ltd. Source

O'Brien T.,Marymount University
Journal of Pain and Palliative Care Pharmacotherapy | Year: 2013

By 2050, it is predicted that 26% of the population will be aged 80 and over. Although older people have much to contribute, one challenging aspect of an aging population is the increasing rate of dementia. Palliative care is now included as part of the care pathway of a wide variety of nonmalignant diseases. The European Association for Palliative Care (EAPC) and the European Union Geriatric Medicine Society (EUGMS) have jointly called for every older citizen with chronic disease to be offered the best possible palliative care approach wherever they are cared for. This report is adapted from paineurope 2013; Issue 2, ©Haymarket Medical Publications Ltd., and is presented with permission. paineurope is provided as a service to pain management by Mundipharma International LTD. and is distributed free of charge to healthcare professionals in Europe. Archival issues can be accessed via the website: http://www.paineurope.com at which European health professionals can register online to receive copies of the quarterly publication. © 2013 Informa Healthcare USA, Inc. Source

Agency: NSF | Branch: Standard Grant | Program: | Phase: EarthCube | Award Amount: 144.40K | Year: 2014

The proposed work addresses a challenge central to the EarthCube programs success: How to employ state of the art technology for geoscience data discovery, access, and integration. The project brings together significant geosciences holdings in the ocean, earth and polar sciences to demonstrate how innovative technologies can be robustly applied to these facilities to enhance the capabilities for scientists to discover and interpret relevant geoscience data and knowledge. The end product, GEOLink, will lower barriers to cross-repository data discovery and access, while respecting and preserving repository autonomy and heterogeneity. They will demonstrate the approach through a portal that allows searching and browsing of integrated content from multiple repositories.

A key challenge for EarthCube is to enable data discovery, access, and integration in a sustainable way. Existing data repositories and networks must be linked, while retaining their independent missions and services to existing disciplinary communities. Cultural, conceptual, and infrastructural heterogeneities must be respected in order to maintain different perspectives and differing priorities and thus foster inclusivity in the EarthCube endeavor. In particular, individual choices made by providers of data or repositories will need to be respected in an inclusive manner, and approaches to integration must reflect this. At the same time, however, the diversity and heterogeneity of geoscience data presents a significant barrier to its discovery. In this project, the researchers involved will develop a demonstration called GEOLink based on: 1) digital publication of geoscience data and knowledge as Linked Open Data; combined with 2) semantic integration using design patterns and vocabularies shared among federated repositories; and 3) an underlying cyberinfrastructure extendable in both depth and breadth, that can become a central building block for EarthCube data harmonization. The cyberinfrastructure underlying the approach is extendable, sustainable, and affordable - leveraging state of the art developments in Linked Open Data and formal semantics, grounded through shared Ontology Design Patterns. GEOLink-enabled repositories will support discovery of related resources, including Rolling Deck to Repository (R2R), the Biological and Chemical Oceanographic Data Management Office (BCO-DMO), Integrated Earth Data Applications (IEDA), the Long-Term Ecological Research Network (LTER), DataONE, and the International Ocean Discovery Program (IODP), as well content from other EarthCube Building Block projects and collaborators.

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