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Alexandria, VA, United States

Loux N.T.,U.S. Environmental Protection Agency | Su Y.S.,825 Mark Center Drive | Hassan S.M.,University of Georgia
International Journal of Environmental Research and Public Health | Year: 2011

Manufactured nanomaterials (MNs) are commonly considered to be commercial products possessing at least one dimension in the size range of 10 -9 m to 10 -7 m. As particles in this size range represent the smaller fraction of colloidal particles characterized by dimensions of 10 -9 m to 10 -6 m, they differ from both molecular species and bulk particulate matter in the sense that they are unlikely to exhibit significant settling under normal gravitational conditions and they are also likely to exhibit significantly diminished diffusivities (when compared to truly dissolved species) in environmental media. As air/water, air/soil, and water/soil inter medium transport is governed by diffusive processes in the absence of significant gravitational and inertial impaction processes in environmental systems, models of MN environmental inter medium transport behavior will likely require an emphasis on kinetic approaches. This review focuses on the likely environmental fate and transport of MNs in atmospheric and aquatic systems. Should significant atmospheric MNs emission occur, previous observations suggest that MNs may likely exhibit an atmospheric residence time of ten to twenty days. Moreover, while atmospheric MN aggregates in a size range of 10 -7 m to 10 -6 m will likely be most mobile, they are least likely to deposit in the human respiratory system. An examination of various procedures including the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal particle suspension stability in water indicates that more sophisticated approaches maybe necessary in order to develop aquatic exposure models of acceptable uncertainty. In addition, concepts such as Critical Coagulation Concentrations and Critical Zeta Potentials may prove to be quite useful in environmental aquatic exposure assessments. © 2011 by the authors; licensee MDPI, Basel, Switzerland.

Tao B.T.,Center for Health Research and Policy | Taylor D.G.,825 Mark Center Drive
Endocrinology and Metabolism Clinics of North America | Year: 2010

This article reviews economic methodologies developed for estimating cost of illness, examines the current literature on diabetes costs, and presents the latest estimates of the economic impact of type 1 diabetes in terms of direct medical costs (ie, treatment costs) and indirect costs (eg, lost wages). © 2010 Elsevier Inc.

Pschierer C.,Corporate Technical Standards | Gilbert B.,Boeing Company | DeBisschop C.,825 Mark Center Drive | Van Der Stricht S.,EUROCONTROL
IEEE Aerospace and Electronic Systems Magazine | Year: 2013

The joint RTCA SC-217/EUROCAE WG-44 committee completed the latest revisions of the AMDB user requirements and interchange specifications DO-272C and DO-291B in 2011. One of the major novelties is the introduction of the ASRN. The ASRN supports manual editing of taxi routes, data link transmissions of taxi routes, and highly detailed display of taxi routes in the cockpit. © 2013 IEEE.

Rosenau W.,825 Mark Center Drive
Studies in Conflict and Terrorism | Year: 2013

This article addresses the gap in the literature on U.S. domestic terrorism and counterterrorism in the 1970s by examining a once-notorious but now largely forgotten terrorist group, the Black Liberation Army (BLA). An outgrowth of the Black Panther Party, the BLA was directly responsible for at least 20 fatalities, making it amongst the most lethal "homegrown" U.S. groups of the period. This article seeks to shed new light on the BLA by exploring its relatively short but violent trajectory. By focusing on the group's origins, operations, ideology, and structure, the BLA can be understood as part of a wider landscape of homegrown political violence. The BLA emerged during the waning phase of a protest cycle that included the civil rights, Black Power, and anti-war movements. Like other terrorist groups before and after, the BLA claimed to be acting in self-defense and on behalf of the people, presenting itself as an army resisting police occupation of minority communities. With the collapse of the extreme Left in the mid- 1970s, the BLA's prospects for creating a broader revolutionary base became remote. The article also examines law-enforcement responses to the BLA and the competing ways in which the Federal Bureau of Investigation and local police (and in particular, the New York Police Department) framed and countered the BLA threat. © Taylor & Francis Group, LLC.

Holguin-Veras J.,Rensselaer Polytechnic Institute | Ozbay K.,Rutgers University | Kornhauser A.,Princeton University | Brom M.A.,Rensselaer Polytechnic Institute | And 5 more authors.
Transportation Research Record | Year: 2011

This paper examines the chief findings of research conducted on policies to foster off-hour deliveries (OHDs) in the New York City metropolitan area. The goal was to estimate the overall impacts of eventual full implementation of an OHD program. As part of the research, a system of incentives was designed for the receivers of deliveries the system combined Global Positioning System (GPS) remote sensing monitoring with GPS-enabled smart phones to induce a shift of deliveries to the off-hours from 7:00 p.m. to 6:00 a.m. The concept was pilot tested in Manhattan by 33 companies that switched delivery operations to the off-hours for a period of 1 month. At the in-depth interviews conducted after the test, the participants reported being very satisfied with the experience. As an alternative to road pricing schemes that target freight carriers, this was the first real-life trial of the use of financial incentives to delivery receivers. The analyses indicate that the economic benefits of a full implementation of the OHD program are in the range of $147 to $193 million per year, corresponding to savings on travel time and environmental pollution for regular-hour traffic as well as productivity increases for the freight industry. The pilot test also highlighted the great potential of unassisted OHD-that is, OHD made without personnel from the receiving establishment present-because almost all participants who used this modality decided to continue receiving OHD even after the financial incentive ended.

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