5,246 research outputs found

    Space based OTV servicing

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    Space based servicing of an orbit transfer vehicle (OTV) was previously outlined in sufficient detail to arrive at OTV and support system servicing requirements. Needed space station facilities and their functional requirements were identified. The impact of logistics and space serviceable design on the OTV design is detailed herein. RL10 derivative rocket engine inspection task times are enumerated

    From Solution Into the Gas Phase: Studying Protein Hydrogen Exchange and Electrospray Ionization Using Molecular Dynamics Simulation

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    Here, we apply Molecular Dynamics (MD) simulations to investigate fundamental aspects of structural mass spectrometry (MS). We first examine microscopic phenomena underlying Hydrogen/Deuterium exchange (HDX). HDX interrogates structural dynamics of proteins by measuring the rate of Deuterium uptake into backbone amides. We perform microsecond MD simulations on ubiquitin to investigate this process. We find that HDX protection often cannot be explained by H‑bonding or solvent accessibility considerations. These findings caution against non-critical use of HDX data in structural contexts. We next use MD to examine the Electrospray ionization (ESI) mechanism of proteins. ESI is a soft ionization technique resulting in the production of gaseous protein ions. The mechanism of ion formation from nanometer sized droplets is unclear. We apply a trajectory stitching MD approach to simulate protein-containing nanodroplets, finding that natively‑folded proteins remain solvated as droplets shrink. Residual charge carriers remain following desolvation, consistent with Dole’s charged residue model

    Some Phases of Legal Education in New Brunswick

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    Experimental infectious pancreatic necrosis infections: propagative or point-source epidemic?

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    AbstractExperimentally initiated epidemics of infectious pancreatic necrosis in rainbow-trout fry were analyzed using a modification of the standard mathematical model for a simple propagative epidemic. Contrary to expectations, the value of the transmission parameter (ÎČ) was inversely related to initial density of susceptible hosts. This anomaly can be explained if we assume that the experimental epidemics were point-source rather than propagative epidemics. The implications of this conclusion for modeling experimental and natural epidemics are discussed

    Insecticide resistance and vector control.

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    Insecticide resistance has been a problem in all insect groups that serve as vectors of emerging diseases. Although mechanisms by which insecticides become less effective are similar across all vector taxa, each resistance problem is potentially unique and may involve a complex pattern of resistance foci. The main defense against resistance is close surveillance of the susceptibility of vector populations. We describe the mechanisms of insecticide resistance, as well as specific instances of resistance emergence worldwide, and discuss prospects for resistance management and priorities for detection and surveillance

    Social Entrepreneurship and Impact Investing Report

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    This report investigates the viability of a range of portfolio interventions designed to leverage new sources of investment finance and to support the growth and investability of new businesses in the Indo-Pacific region, with a particular focus on the development of social enterprises. While some of these interventions are relatively new within the aid sector, others are designed to take a fresh perspective on an existing activity. The report sets out the findings for each of the interventions and while interventions were wide ranging, they all form key components of an entrepreneur’s journey and their ultimate participation in an impact investing marketplace. The study focused on the development of new businesses in the region and considers how early stage enterprises could be funded; how entrepreneurs (and particularly social entrepreneurs) could be incubated and supported to develop their business skills; how new financing structures could be deployed by government to attract more private investment into the sector; and the role of platforms in connecting enterprises and sources of capital in brokering deals
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