155 research outputs found

    A flexible, extensible object oriented real-time near photorealistic visualization system:the system framework design

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    In this paper we describe a novel, extensible visualization system currently under development at Aston University. We introduce modern programming methods, such as the use of data driven programming, design patterns, and the careful definition of interfaces to allow easy extension using plug-ins, to 3D landscape visualization software. We combine this with modern developments in computer graphics, such as vertex and fragment shaders, to create an extremely flexible, extensible real-time near photorealistic visualization system. In this paper we show the design of the system and the main sub-components. We stress the role of modern programming practices and illustrate the benefits these bring to 3D visualization. © 2006 Springer-Verlag Berlin Heidelberg

    Cyclin-Dependent Kinase Activity Controls the Onset of the HCMV Lytic Cycle

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    The onset of human cytomegalovirus (HCMV) lytic infection is strictly synchronized with the host cell cycle. Infected G0/G1 cells support viral immediate early (IE) gene expression and proceed to the G1/S boundary where they finally arrest. In contrast, S/G2 cells can be infected but effectively block IE gene expression and this inhibition is not relieved until host cells have divided and reentered G1. During latent infection IE gene expression is also inhibited, and for reactivation to occur this block to IE gene expression must be overcome. It is only poorly understood which viral and/or cellular activities maintain the block to cell cycle or latency-associated viral IE gene repression and whether the two mechanisms may be linked. Here, we show that the block to IE gene expression during S and G2 phase can be overcome by both genotoxic stress and chemical inhibitors of cellular DNA replication, pointing to the involvement of checkpoint-dependent signaling pathways in controlling IE gene repression. Checkpoint-dependent rescue of IE expression strictly requires p53 and in the absence of checkpoint activation is mimicked by proteasomal inhibition in a p53 dependent manner. Requirement for the cyclin dependent kinase (CDK) inhibitor p21 downstream of p53 suggests a pivotal role for CDKs in controlling IE gene repression in S/G2 and treatment of S/G2 cells with the CDK inhibitor roscovitine alleviates IE repression independently of p53. Importantly, CDK inhibiton also overcomes the block to IE expression during quiescent infection of NTera2 (NT2) cells. Thus, a timely block to CDK activity not only secures phase specificity of the cell cycle dependent HCMV IE gene expression program, but in addition plays a hitherto unrecognized role in preventing the establishment of a latent-like state

    Using data fusion of DMARS-R-IMU and GPS data for improving attitude determination accuracy

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    The Mobile Rocket Base (MORABA), a division of the Space Operations and Astronaut Training Department of the German Aerospace Center, has developed and flown sounding rocket rate and attitude control systems since 1972. For determining position and attitude, some of the past missions have used a DMARS-R (Digital Miniature Attitude Reference System) roll stabilized platform produced by the Inertial Science Company. The DMARS-R is a high-precision, roll-stabilized IMU (Inertial Measurement Unit) comprising accurate angular rate and acceleration sensors and mounted on a roll-stabilized platform. Standard IMUs are inherently subject to drift in inertial position, velocity and attitude. By the fusion of GPS and with DMARS-R data, one can achieve a long-term drift-corrected IMU enabling for longer duration flight applications, such as satellite launchers, spin stabilized rockets and balloons. The main experiment of the MAIUS mission, initially planned for autumn 2015, requires accurate pointing to the Earth’s gravitational center. The required accuracy will be obtained by the fusion of DMARS-R and GNS data to produce “drift free” attitude data for the cold gas attitude control system of the payload. The attitude correction and control algorithm will be implemented in the DMARS-R processor

    Thermal and mechanical design of the MAIUS atom interferometer sounding rocket payload

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    RFID - Radio Frequency Identification: Anwendung im Gesundheitswesen und der Medizintechnik

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    Thrifty Final Gather for Radiosity

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