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Vienna, VA, United States

Ab initio calculations have been performed to model the molecular adsorption of dimethyl methylphosphonate (DMMP) on the (001) surface of the anatase form of TiO2. Both the relaxed unreconstructed (1 × 1)- and the (4 × 1)-reconstructed clean surfaces have been analyzed. Adsorption occurs via a Ti - -O=P dative bond to a coordinatively unsaturated surface Ti site. In both cases, one of the two Ti-O-Ti bridge bonds at the Ti adsorption site breaks leading to the formation of a stable Ti=O titanyl group. This species has not been reported in previous studies of adsorption on TiO 2 surfaces but is seen, in the present work, as an intermediate in the dissociative adsorption of H2O. © 2011 by the American Chemical Society. Source

LaForce F.M.,Washington Technology | Okwo-Bele J.-M.,World Health Organization
Health Affairs | Year: 2011

A new affordable vaccine against Group A meningococcus, the most common cause of large and often fatal African epidemics of meningitis, was introduced in Burkina Faso, Mali, and Niger in 2010. Widespread use of the vaccine throughout much of Africa may prevent more than a million cases of meningitis over the next decade. The new vaccine is expected to be cost-saving when compared to current expenditures on these epidemics; for example, an analysis shows that introducing it in seven highly endemic countries could save $350 million or more over a decade. International donors have already committed funds to support the new vaccine's introduction in Burkina Faso, Niger, and Mali, but an estimated US$400 million is needed to fund mass immunization campaigns in people ages 1-29 over six years in all twentyfive countries of the African meningitis belt. The vaccine's low cost-less than fifty cents per dose-makes it possible for the affected countries themselves to purchase vaccines for future birth cohorts. © 2011 Project HOPE-The People-to-People Health Foundation, Inc. Source

Rowenhorst D.J.,Washington Technology | Voorhees P.W.,Northwestern University
Annual Review of Materials Research | Year: 2012

The experimental measurement of the evolution of interfaces in three dimensions is reviewed, concentrating on the evolution of polycrystalline and solid-liquid systems, including growth and coarsening in dendritic systems and evolution during liquid-phase sintering. Both ex situ destructive techniques and in situ nondestructive techniques are considered. The importance of making three-dimensional measurements that can be quantified and unambiguously compared with theory is discussed, showing that these measurements provide a direct validation of theory and critical initial conditions for simulations. © Copyright ©2012 by Annual Reviews. All rights reserved. Source

McGraw D.,Washington Technology
Journal of the American Medical Informatics Association | Year: 2013

Objectives The aim of this paper is to summarize concerns with the de-identification standard and methodologies established under the Health Insurance Portability and Accountability Act (HIPAA) regulations, and report some potential policies to address those concerns that were discussed at a recent workshop attended by industry, consumer, academic and research stakeholders. Target audience The target audience includes researchers, industry stakeholders, policy makers and consumer advocates concerned about preserving the ability to use HIPAA de-identified data for a range of important secondary uses. Scope HIPAA sets forth methodologies for de-identifying health data; once such data are de-identified, they are no longer subject to HIPAA regulations and can be used for any purpose. Concerns have been raised about the sufficiency of HIPAA de-identification methodologies, the lack of legal accountability for unauthorized reidentification of de-identified data, and insufficient public transparency about de-identified data uses. Although there is little published evidence of the re-identification of properly de-identified datasets, such concerns appear to be increasing. This article discusses policy proposals intended to address de-identification concerns while maintaining de-identification as an effective tool for protecting privacy and preserving the ability to leverage health data for secondary purposes. Source

Pique A.,Washington Technology
Applied Physics A: Materials Science and Processing | Year: 2011

This review discusses the origins and evolution of the MAPLE technique as it started as an alternative to spray coating of thin films for chemical vapor sensors. It describes its numerous applications for the deposition of thin films of polymeric, organic and biomaterials for various applications. This is followed by an overview of several new variations of the MAPLE technique. This review concludes with an outlook on the future of this highly versatile and successful vapor deposition process. © 2011 Springer-Verlag (outside the USA). Source

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