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Dimech W.,NRL | Grangeot-Keros L.,University Paris - Sud | Vauloup-Fellous C.,University Paris - Sud
Clinical Microbiology Reviews | Year: 2016

Rubella virus usually causes a mild infection in humans but can cause congenital rubella syndrome (CRS). Vaccination programs have significantly decreased primary rubella virus infection and CRS; however, vaccinated individuals usually have lower levels of rubella virus IgG than those with natural infections. Rubella virus IgG is quantified with enzyme immunoassays that have been calibrated against the World Health Organization (WHO) international standard and report results in international units per milliliter. It is recognized that the results reported by these assays are not standardized. This investigation into the reasons for the lack of standardization found that the current WHO international standard (RUB-1-94) fails by three key metrological principles. The standard is not a pure analyte but is composed of pooled human immunoglobulin. It was not calibrated by certified reference methods; rather, superseded tests were used. Finally, no measurement uncertainty estimations have been provided. There is an analytical and clinical consequence to the lack of standardization of rubella virus IgG assays, which leads to misinterpretation of results. The current approach to standardization of rubella virus IgG assays has not achieved the desired results. A new approach is required. © 2015, American Society for Microbiology. All Rights Reserved. Source


News Article
Site: http://www.nrl.navy.mil/media/news-releases/

A five-member team of researchers from the U.S. Naval Research Laboratory (NRL) Center for Corrosion Science and Engineering received the Office of Naval Research (ONR) Prize for Affordability, Aug. 26, at an award ceremony held at ONR in Alexandria, Va. The award honors materials research engineers James Martin, head of the Marine Coatings Science Section, Jimmy Tagert, and John Wegand; research chemist, Dr. Erick Iezzi; and physical scientist technician, Paul Slebodnick for significant contributions to an overall reduction in the total ownership costs associated with corrosion control of Navy ships and submarines and achievements in the development and transition of nonskid and topside coatings to the fleet. The team formulated, synthesized, and commercialized topside and nonskid coatings having longer life, high durability, improved weathering resistance and color stability, to replace both legacy nonskid decking and topside coatings. The Navy installs nearly 3.7 million square feet of non-skid coatings per year that typically cost over $56 million annually. Conventional epoxy based nonskids have a 12 to 36 month lifecycle, while topside coatings have a 24 to 36 month life. The new NRL-developed polysiloxane system doubles or triples the life expectancy of this system. For topside coatings, not only are lifetimes increased, but also installation costs are reduced by up to 28 percent through the reduced number of coats over conventional systems. As a result, polysiloxane coatings systems have been qualified and approved for use by Naval Sea Systems Command (NAVSEA) and have been mandated for all topside depot level maintenance availabilities. The NRL polysiloxane nonskid decking system is planned for qualification in 2015. At present, the nonskid coatings system has exceeded the one-year flight deck requirement on-board the USS Theodore Roosevelt (CVN 71), has outperformed all previous nonskids on-board the USS Michigan (SSGN 727), and is still performing well on-board the USS Bulkeley (DDG 84). On Navy submarines, this system is the only system ever to pass the submarine nonskid requirements. The Center for Corrosion Science and Engineering (CCSE) conducts broad scientific and engineering programs to understand and reduce the effects of the marine environment on naval systems. Within the CCSE, the Marine Coatings Science Section conducts basic and applied research to synthesize and produce advanced, multi-functional marine coatings technology for all naval environments including immersion, alternate immersion and atmospheric exposures typical of Navy and Marine Corps platforms. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


News Article
Site: http://phys.org/technology-news/

During the weeks of September 28 and October 26, the team launched 23 flights over a nine-day period resulting in greater than 30 hours of combined flight. The tests, conducted within restricted airspace at Phillips Army Airfield, Aberdeen Proving Grounds, culminated with two 'powered' sailplanes sharing telemetry data and cooperatively and autonomously soaring at altitudes in excess of one kilometer and for flight durations of over five hours. The NRL-developed Autonomous Locator of Thermals (ALOFT) autonomous soaring algorithm guided NRL's aircraft. The PSU aircraft was guided onboard by the AVIA-developed AutoSOAR autonomous soaring algorithm, which drew inspiration from NRL's ALOFT techniques. AutoSOAR's addition of a series of atmospheric mapping and collision avoidance algorithms demonstrated in-flight cooperation between the two aircraft on multiple flights. "Autonomous soaring algorithms seek out naturally occurring areas of rising air called thermals," said Dr. Dan Edwards, aerospace engineer and principle investigator of the solar-soaring program. "Cooperative autonomous soaring combines data from multiple autonomous soaring aircraft to make a more complete measurement of the local atmospheric conditions. This atmospheric map is then integrated to guide both aircraft toward strong lift activity quicker than if it was just a single aircraft, a technique very similar to that used by a flock of soaring birds." Both aircraft demonstrated a robust autonomous soaring capability during the two weeks of testing. PSU's aircraft flew multiple 2.5-hour flights despite carrying a battery with only enough capacity for four minutes of motor run-time. NRL's best soaring flight was 5.3 hours while only running a motor-driven propeller for 27 minutes. Both aircraft rode thermals to altitudes in excess of 1,400 meters with several individual climbs in excess of 1,000 meters using nothing more than the power of the atmosphere. "These tests showed both the NRL and PSU's autonomous soaring algorithms are successful at finding and using thermals by themselves," Edwards said. "More importantly, this testing showed proof of concept on multiple occasions, with both aircraft finding thermals and 'calling' the other aircraft over to use the same area of lift to increase endurance of the swarm." Future testing will focus on reducing the separation distance such that both aircraft can actively soar in the same thermal at the same altitude. The team will also investigate the inclusion of solar photovoltaics to the cooperative autonomous soaring techniques, enabling long endurance flights of unmanned sailplanes using the power of the sun. Solar photovoltaics will allow conversion of solar radiation directly to electricity to charge batteries or provide power for longer endurance or payloads. NRL is developing "drop-in" power electronics and solar wings, which will enable charging batteries and aiming for overnight flight. The Solar Photovoltaic and Autonomous Soaring Base Program and the US Marine Corps' Expeditionary Energy Office Cooperative-Soaring Program are aimed to improve the availability of a 24-7 Information, Surveillance, and Reconnaissance (ISR) mission without using logistics fuel, benefitting the expeditionary warfighter by enhancing the endurance of existing and future UAV assets.


News Article
Site: http://www.nrl.navy.mil/media/news-releases/

The U.S. Naval Research Laboratory (NRL), in collaboration with the Air Vehicle Intelligence and Autonomy (AVIA) Lab at Pennsylvania State University (PSU), completed testing of cooperative autonomous soaring algorithms used to keep unmanned sailplanes aloft for sustained flight durations - demonstrating the concept of shared soaring data between two unmanned aerial vehicles (UAVs) in flight. During the weeks of September 28 and October 26, the team launched 23 flights over a nine-day period resulting in greater than 30 hours of combined flight. The tests, conducted within restricted airspace at Phillips Army Airfield, Aberdeen Proving Grounds, culminated with two 'powered' sailplanes sharing telemetry data and cooperatively and autonomously soaring at altitudes in excess of one kilometer and for flight durations of over five hours. The NRL-developed Autonomous Locator of Thermals (ALOFT) autonomous soaring algorithm guided NRL's aircraft. The PSU aircraft was guided onboard by the AVIA-developed AutoSOAR autonomous soaring algorithm, which drew inspiration from NRL's ALOFT techniques. AutoSOAR's addition of a series of atmospheric mapping and collision avoidance algorithms demonstrated in-flight cooperation between the two aircraft on multiple flights. "Autonomous soaring algorithms seek out naturally occurring areas of rising air called thermals," said Dr. Dan Edwards, aerospace engineer and principle investigator of the solar-soaring program. "Cooperative autonomous soaring combines data from multiple autonomous soaring aircraft to make a more complete measurement of the local atmospheric conditions. This atmospheric map is then integrated to guide both aircraft toward strong lift activity quicker than if it was just a single aircraft, a technique very similar to that used by a flock of soaring birds." Both aircraft demonstrated a robust autonomous soaring capability during the two weeks of testing. PSU's aircraft flew multiple 2.5-hour flights despite carrying a battery with only enough capacity for four minutes of motor run-time. NRL's best soaring flight was 5.3 hours while only running a motor-driven propeller for 27 minutes. Both aircraft rode thermals to altitudes in excess of 1,400 meters with several individual climbs in excess of 1,000 meters using nothing more than the power of the atmosphere. "These tests showed both the NRL and PSU's autonomous soaring algorithms are successful at finding and using thermals by themselves," Edwards said. "More importantly, this testing showed proof of concept on multiple occasions, with both aircraft finding thermals and 'calling' the other aircraft over to use the same area of lift to increase endurance of the swarm." Future testing will focus on reducing the separation distance such that both aircraft can actively soar in the same thermal at the same altitude. The team will also investigate the inclusion of solar photovoltaics to the cooperative autonomous soaring techniques, enabling long endurance flights of unmanned sailplanes using the power of the sun. Solar photovoltaics will allow conversion of solar radiation directly to electricity to charge batteries or provide power for longer endurance or payloads. NRL is developing "drop-in" power electronics and solar wings, which will enable charging batteries and aiming for overnight flight. The Solar Photovoltaic and Autonomous Soaring Base Program and the US Marine Corps' Expeditionary Energy Office Cooperative-Soaring Program are aimed to improve the availability of a 24-7 Information, Surveillance, and Reconnaissance (ISR) mission without using logistics fuel, benefitting the expeditionary warfighter by enhancing the endurance of existing and future UAV assets. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


News Article
Site: http://www.nrl.navy.mil/media/news-releases/

U.S. Naval Research Laboratory (NRL) research physicist, Dr. Carl Stephen Hellberg, is elected Fellow by the American Physical Society (APS) for creative and influential contributions in the fields of strongly correlated materials, quantum dots, defects, and heterostructures. Arriving at NRL in 1996 as a National Research Council (NRC) research associate, Hellberg has concentrated on researching the physics of surfaces and interfaces using density functional theory, concentrating on low-dimensional systems and the surfaces and interfaces of bulk crystals. "Dr. Hellberg is recognized for his work demonstrating the limits of strontium titanate to coherently grow beyond a few layers on silicon and how chemical substitutions at the interface can produce a better interface and more uniform thin films," said Dr. Michael Mehl, head, Center for Computational Material Science. "I am very delighted he has been elected a Fellow of the American Physical Society for his groundbreaking work in the field of computational physics." Hellberg's current research includes first principles calculations of surfaces, interfaces, and thin films. He is focusing on oxides and chalcogenides, including polarity mismatched interfaces, topological insulators, and monolayer heterostructures, with a particular interests in electrical properties and metal-insulator transitions. He also works on strongly correlated electron systems, including quantum dots, nanocrystals, and transition metal oxides. Hellberg received his undergraduate degree in physics from Princeton University in 1987, and then studied for a year at the Ludwig Maximilian University of Munich on a Fulbright Fellowship. He enrolled in graduate school at the University of Pennsylvania, where he worked with professor Eugene J. Mele, receiving his Ph.D. in 1993. He spent three years working with professor Efstratios Manousakis at Florida State University in a postdoctoral appointment developing computational techniques to study strongly correlated electrons. The APS is a non-profit membership organization working to advance and diffuse the knowledge of physics. APS Fellows are elected on the criterion of exceptional contributions to the physics enterprise that are comprised of outstanding physics research, important applications of physics, leadership in or service to physics, or significant contributions to physics education. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.

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