1,350 research outputs found

    Tools for the analysis of the landscape structure and its configuration and resilience.

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    The st udy wi l l pr o po se an application on Cilento’s rural landscape to test a method of analysing the syntactical aspects and of identifying the dynamics of transformation in order to control changes and to define those elements that are resilient to change and how they can be modified to be consistent with emerging new needs. The perceptual dimension of the landscape is affected by many factors that may give rise to numerous and different evaluations; the study, by identifying the syntactic elements and the rules that govern the composition of a perspective system, allows the orderly return of what is recognized by the experiential memory. The study is aimed to define tools in order to educate the residents to avoid insertions or removals, booth natural or artificial components, inconsistent with the rules that govern the identity of the landscape

    Resilience and circularity in sustainable building design. Integrated tools for pre-intervention assessment

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    The new demands on environmental protection and the energy efficiency of architectural assets open new frontiers to studies for the development of technologies for the control of the building process. The study presented here aims to identify criteria and tools for the control of resilience and circularity factors in construction as moderators of obsolescence processes, capable of stabilizing the construction product in ecosystem growth. The work integrates the results of two ongoing doctoral types of research that address the issue of controlling resilience and circularity in construction as a strategy for reducing environmental impact by identifying specific methodologies for interventions on the built heritage and the digital design process of new buildings

    Fluid dynamic characterization of a polymeric heart valve prototype (Poli-Valve) tested under continuous and pulsatile flow conditions.

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    PURPOSE: Only mechanical and biological heart valve prostheses are currently commercially available. The former show longer durability but require anticoagulant therapy; the latter display better fluid dynamic behavior but do not have adequate durability. New Polymeric Heart Valves (PHVs) could potentially combine the hemodynamic properties of biological valves with the durability of mechanical valves. This work presents a hydrodynamic evaluation of 2 groups of newly developed supra-annular, trileaflet prosthetic heart valves made from styrenic block copolymers (SBC): Poli-Valves. METHODS: 2 types of Poli-Valves made of SBC and differing in polystyrene fraction content were tested under continuous and pulsatile flow conditions as prescribed by ISO 5840 Standard. A pulse duplicator designed ad hoc allowed the valve prototypes to be tested at different flow rates and frequencies. Pressure and flow were recorded; pressure drops, effective orifice area (EOA), and regurgitant volume were computed to assess the behavior of the valve. RESULTS: Both types of Poli-Valves met the minimum requirements in terms of regurgitation and EOA as specified by the ISO 5840 Standard. Results were compared with 5 mechanical heart valves (MHVs) and 5 tissue heart valves (THVs), currently available on the market. CONCLUSIONS: Based on these results, PHVs based on styrenic block copolymers, as are Poli-Valves, can be considered a promising alternative for heart valve replacement in the near future.This work was funded by the British Heart Foundation, New Horizons grant NH/11/4/29059.This is the final version of the article. It first appeared from Wichtig Publishing via http://dx.doi.org/10.5301/ijao.500045

    A Newly Developed Tri-Leaflet Polymeric Heart Valve Prosthesis.

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    The potential of polymeric heart valves (PHV) prostheses is to combine the hemodynamic performances of biological valves with the durability of mechanical valves. The aim of this work is to design and develop a new tri-leaflet prosthetic heart valve (HV) made from styrenic block copolymers. A computational finite element model was implemented to optimize the thickness of the leaflets, to improve PHV mechanical and hydrodynamic performances. Based on the model outcomes, 8 prototypes of the designed valve were produced and tested in vitro under continuous and pulsatile flow conditions, as prescribed by ISO 5840 Standard. A specially designed pulse duplicator allowed testing the PHVs at different flow rates and frequency conditions. All the PHVs met the requirements specified in ISO 5840 Standard in terms of both regurgitation and effective orifice area (EOA), demonstrating their potential as HV prostheses.This work was funded by the British Heart Foundation (New Horizons NH/11/4/29059).This is the final published version. It first appeared at http://www.worldscientific.com/doi/abs/10.1142/S0219519415400096?src=recsys

    El efecto del papel mediador de la comunicaci?n de la responsabilidad social empresarial en la relaci?n entre la responsabilidad social empresarial y el desempe?o financiero: Un an?lisis en la industria pesquera del Per?

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    A lo largo de los ?ltimos a?os, han surgido un mayor n?mero de empresas interesadas en la Responsabilidad Social Empresarial (RSE) como un eje fundamental para poder cumplir con sus objetivos econ?micos, sociales y medioambientales en las comunidades donde realizan sus actividades. En ese sentido, se esperar?a que la RSE generar? beneficios financieros para las empresas; sin embargo, los resultados en la literatura no han sido concluyentes respecto a esta relaci?n. Por ello, investigaciones recientes proponen la adici?n de variables mediadoras tales como la comunicaci?n de la RSE para capturar mejor esta relaci?n. En ese sentido, se propone un modelo cuantitativo aplicado a la industria pesquera peruana que incorpora la comunicaci?n de la RSE como variable mediadora en la relaci?n entre la RSE y desempe?o financiero. Asimismo, se plantean estrategias de recolecci?n de datos a trav?s de encuestas en 105 empresas y la formulaci?n del modelo. Se espera que este trabajo contribuya a la literatura sobre la RSE y los beneficios de su aplicaci?n en cada una de sus dimensiones, base sobre la cual las empresas podr?n tomar decisiones m?s informadas sobre la aplicaci?n de RSE
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