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H7 avian influenza viruses represent a major public health concern, and worldwide outbreaks raise the risk of a potential pandemic. Understanding the memory B cell response to avian (H7) influenza virus infection in humans could provide insights in the potential key to human infection risks. We investigated an epizootic of the highly pathogenic A(H7N7) in the Netherlands, which in 2003 led to infection of 89 persons and one fatal case. Subtype-specificity of antibodies were determined for confirmed H7N7 infected individuals (cases) (n = 19), contacts of these cases (n = 21) and a comparison group controls (n = 16), by microarray, using recombinant hemagglutinin (HA)1 proteins. The frequency and specificity of memory B cells was determined by detecting subtype-specific antibodies in the culture supernatants from in vitro stimulated oligoclonal B cell cultures, from peripheral blood of cases and controls. All cases (100%) had high antibody titers specific for A(H7N7)2003 (GMT > 100), whereas H7-HA1 antigen binding was detected in 29% of contacts and 31% of controls, suggesting that some of the H7 reactivity stems from cross reactive antibodies. To unravel homotypic and heterotypic responses, the frequency and specificity of memory B cells were determined in 2 cases. Ten of 123 HA1 reactive clones isolated from the cases bound to only H7- HA1, whereas 5 bound both H7 and other HA1 antigens. We recovered at least four different epitopal reactivities, though none of the H7 reactive antibodies were able to neutralize H7 infections in vitro. Our study serologically confirms the infection with H7 avian influenza viruses, and shows that H7 infection triggers a mixture of strain -specific and cross-reactive antibodies.

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For Navy relevant geometries, separation of wall bounded flows is a highly complex phenomenon. The combination of three-dimensionality and unsteadiness results in a highly complex time-dependent topology of the separated region. In a combined numerical/experimental effort we investigated laminar separation bubbles in external flows. We employed highly-resolved direct numerical simulations to obtain a deeper understanding of the various physical mechanism governing separation, transition, and reattachment. We also carried out and hybrid RANS/LES simulations for a turbulent square-duct and the Stanford University asymmetric diffuser., The original document contains color images. All DTIC reproductions will be in black and white.

We present the U-series dating of bones from Wood Quarry ('Steetley Quarry Cave') using the diffusion-adsorption model to account for uranium uptake. The results give a weighted mean date of 66.8 ± 3.0 kyr, placing this assemblage within or just before M