Activity of a dry mist-generated hydrogen peroxide disinfection system against methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii

Background: The aim of this study was to evaluate the activity of a dry mist-generated hydrogen peroxide (DMHP) system (Sterinis; Gloster Sante Europe, Labege cedex, France) against methicillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii. Methods: McFarland 0.5 suspensions of 2 test bacteria, either pure or containing 5% sterile serum, were prepared and inoculated onto sterile stainless steel disks. Each disk in a Petri dish - with the Petri dish cover either closed or open - was placed in different locations in an intensive care unit room. Quantitative cultures were performed after the cycle. Results: No growth occurred on the disks in the absence of a barrier, except 1 disk containing serum. Existence of a barrier, as a drawer or a covered Petri dish, caused failure in the disinfection activity. The mean reduction in initial log 10 bacterial count was lower for both of the test bacteria in presence of a barrier: 4.44- to 4.70-log 10 colony-forming units (cfu) decrease was observed in absence of a barrier, whereas 1.49- to 3.79-log 10 cfu decrease was observed in presence of a barrier. When the culture results were compared according to organic load content, the mean (±standard deviation) reduction of initial contamination in pure and in serum containing MRSA suspensions was 4.25 ± 1.20- and 3.34 ± 1.89-log 10 cfu, respectively. The mean (±standard deviation) reduction in pure and in serum containing A baumannii suspensions was 4.34 ± 0.89- and 3.87 ± 1.26-log 10 cfu, respectively. The differences were statistically significant (P <.001). Conclusion: Sterinis was capable of killing MRSA and A baumannii on open surfaces; however, it was not effective in closed or semiclosed areas. Presence of serum also caused failure in the disinfection activity of the system. Copyright © 2011 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved

Analysis and Design Optimization of Blunt Bodies In Hypersonic Flow

The purpose of this study is to model hypersonic flow around blunt body especially in atmospheric reentry of Earth. The more detailed model contains each energy transformation between each energy modes and all reactions. To simulate flow field region, thermal and chemical nonequilibrium must be considered all together. For the chemical nonequilibrium, species masses production of reactions must be characterized with suitable model. In this study, flow analysis based on the finite rate chemical reaction equations. Flow field region is assumed as continuum. Also flow is considered as inviscid and there is no diffusion. Computation of flow field is based on the axisymmetric Euler code. Coupled equations, chemical and thermal nonequilibrium equations are solved by using Newton's method. Jacobian matrices are calculated analytically. In the design part, aim is to obtain reduced pressure drag while keeping the body as blunt. Optimization results for various situations are represented

Analysis and Adjoint Design Optimization of Hypersonic Blunt Bodies

© 2014 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.The main purpose of this study is to analyze hypersonic flow field around the blunt bodies and to design of that bodies in order to obtain minimum pressure drag. Modeling of non-equilibrium must be done properly. In this study, non-equilibriums of thermal and chemical modes are considered. Translational and rotational energy modes are assumed that energy exchange between these modes is so fast. Vibrational and electronic energy terms are neglected. Therefore, one temperature is used to model thermo-chemical non-equilibrium. Flow field is assumed as inviscid and continuum region. Moreover, there is not diffusion. Thus, to model chemical non-equilibrium, finite rate chemistry can be used. For the thermal- nonequilibrium, enthalpy, entropy and specific heat constants are obtained from curve fitting methods. The coupled flow field equations are solved by using Newton’s methods. To solve Newton’s method, Jacobian matrices evaluation is required. In terms of convergence, Jacobian matrices are obtained by using analytical methods. At the design part, sensitivities are obtained by using adjoint design methods. The aim of design part is finding a hypersonic blunt geometry with minimum pressure drag while keeping the maximum temperature smaller than the baseline value

Aerothermodynamic Design Optimization in Hypersonic Flows

© 2013, American Institute of Aeronautics and Astronautics Inc. All rights reserved.The objective of this study is to develop a reliable and efficient design tool that can be used in hypersonic flows. The flow analysis is based on the axisymmetric Euler and the finite rate chemical reaction equations. These coupled equations are solved by using Newton’s method. The analytical and numerical methods are used to calculate Jacobian matrices. The effects of error in numerical Jacobians on the performance of flow and sensitivity analyses are studied. A gradient based numerical optimization is used. Sensitivities are calculated by using finite-difference, direct differentiation and adjoint methods. The objective of the design is to generate a hypersonic blunt geometry that produces the minimum pressure drag while keeping the maximum temperature smaller than the initial value. Bezier curves are used for geometry modification. The performance of the optimization method is demonstrated for different hypersonic flow conditions

QROWD: a platform for integrating citizens in smart city data analytics

Optimizing mobility services is one of the greatest challenges Smart Cities face in their efforts to improve residents’ wellbeing and reduce emissions. The advent of IoT has created unparalleled opportunities to collect large amounts of data about how people use transportation. This data could be used to ascertain the quality and reach of the services offered and to inform future policy—provided cities have the capabilities to process, curate, integrate and analyse the data effectively. At the same time, to be truly ‘Smart’, cities need to ensure that the data-driven decisions they make reflect the needs of their citizens, create feedback loops, and widen participation. In this chapter, we introduce QROWD, a data integration and analytics platform that seamlessly integrates multiple data sources alongside human, social and computational intelligence to build hybrid, automated data-centric workflows. By doing so, QROWD applications can take advantage of the best of both worlds: the accuracy and scale of machine computation, and the skills, knowledge and expertise of people. We present the architecture and main components of the platform, as well as its usage to realise two mobility use cases: estimating the modal split, which refers to trips people take that involve more than one type of transport, and urban auditing.</p