2,913 research outputs found
Nociones fundamentales de estática gráfica
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 201
Natural ventilation for the prevention of airborne contagion.
BACKGROUND: Institutional transmission of airborne infections such as tuberculosis (TB) is an important public health problem, especially in resource-limited settings where protective measures such as negative-pressure isolation rooms are difficult to implement. Natural ventilation may offer a low-cost alternative. Our objective was to investigate the rates, determinants, and effects of natural ventilation in health care settings. METHODS AND FINDINGS: The study was carried out in eight hospitals in Lima, Peru; five were hospitals of "old-fashioned" design built pre-1950, and three of "modern" design, built 1970-1990. In these hospitals 70 naturally ventilated clinical rooms where infectious patients are likely to be encountered were studied. These included respiratory isolation rooms, TB wards, respiratory wards, general medical wards, outpatient consulting rooms, waiting rooms, and emergency departments. These rooms were compared with 12 mechanically ventilated negative-pressure respiratory isolation rooms built post-2000. Ventilation was measured using a carbon dioxide tracer gas technique in 368 experiments. Architectural and environmental variables were measured. For each experiment, infection risk was estimated for TB exposure using the Wells-Riley model of airborne infection. We found that opening windows and doors provided median ventilation of 28 air changes/hour (ACH), more than double that of mechanically ventilated negative-pressure rooms ventilated at the 12 ACH recommended for high-risk areas, and 18 times that with windows and doors closed (p < 0.001). Facilities built more than 50 years ago, characterised by large windows and high ceilings, had greater ventilation than modern naturally ventilated rooms (40 versus 17 ACH; p < 0.001). Even within the lowest quartile of wind speeds, natural ventilation exceeded mechanical (p < 0.001). The Wells-Riley airborne infection model predicted that in mechanically ventilated rooms 39% of susceptible individuals would become infected following 24 h of exposure to untreated TB patients of infectiousness characterised in a well-documented outbreak. This infection rate compared with 33% in modern and 11% in pre-1950 naturally ventilated facilities with windows and doors open. CONCLUSIONS: Opening windows and doors maximises natural ventilation so that the risk of airborne contagion is much lower than with costly, maintenance-requiring mechanical ventilation systems. Old-fashioned clinical areas with high ceilings and large windows provide greatest protection. Natural ventilation costs little and is maintenance free, and is particularly suited to limited-resource settings and tropical climates, where the burden of TB and institutional TB transmission is highest. In settings where respiratory isolation is difficult and climate permits, windows and doors should be opened to reduce the risk of airborne contagion
Cédula, 1778-07-09
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2012-2013Certifica la copia, Antonio Martinez SalazarTexto fechado en Aranjuez, 9 de Julio de 1778Sign.: [ ]6Port. con esc. real xil
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How have advances in comparative floral development influenced our understanding of floral evolution?
Evolutionary developmental biology has come to prominence in the past two decades, in both the plant kingdom and the animal kingdom, particularly following the description of homeotic genes linked to key morphological transitions. A primary goal of evolutionary developmental biology (“evo-devo”) is to define how developmental programs are modified to generate novel or labile morphologies. This requires an understanding of the molecular genetic basis of these programs and of the evolutionary changes they have undergone. The past decade has seen the establishment of a common language and common standards, and these changes have greatly improved the integration of evo-devo. Recently, a more comparative approach has been added to mechanistic developmental biology. In this review we attempt to show how, by using this “next-generation evo-devo” approach, insights into both developmental biology and evolutionary biology can be gained. Although the concepts we discuss are more broadly applicable, we have focused our examples on traits of the angiosperm flower, a structure that has undergone enormous morphological and developmental evolution since its relatively recent appearance in the fossil record.Work in the Glover laboratory on these topics is funded by the BBSRC, EU Marie Curie Actions, Isaac Newton Trust, Leverhulme Trust, NERC and the NSF, and we gratefully acknowledge all support.This is the accepted manuscript of a paper published in the International Journal of Plant Sciences (Glover BJ, Airoldi CA, Brockington SF, Fernández-Mazuecos M, Martínez-Pérez C, Mellers G, Moyroud E, Taylor L, International Journal of Plant Sciences, 2015, 176, 4, 307-323, doi:10.1086/681562). The final version is available at http://dx.doi.org/10.1086/68156
Geographically distributed hybrid testing & collaboration between geotechnical centrifuge and structures laboratories
© 2018, Institute of Engineering Mechanics (IEM). All rights reserved. Distributed Hybrid Testing (DHT) is an experimental technique designed to capitalise on advances in modern networking infrastructure to overcome traditional laboratory capacity limitations. By coupling the heterogeneous test apparatus and computational resources of geographically distributed laboratories, DHT provides the means to take on complex, multi-disciplinary challenges with new forms of communication and collaboration. To introduce the opportunity and practicability afforded by DHT, here an exemplar multi-site test is addressed in which a dedicated fibre network and suite of custom software is used to connect the geotechnical centrifuge at the University of Cambridge with a variety of structural dynamics loading apparatus at the University of Oxford and the University of Bristol. While centrifuge time-scaling prevents real-time rates of loading in this test, such experiments may be used to gain valuable insights into physical phenomena, test procedure and accuracy. These and other related experiments have led to the development of the real-time DHT technique and the creation of a flexible framework that aims to facilitate future distributed tests within the UK and beyond. As a further example, a real-time DHT experiment between structural labs using this framework for testing across the Internet is also presented
Psychological type and prayer preferences: a study among Anglican clergy in the United Kingdom
This study applies the framework of Jungian psychological type theory to define eight aspects of prayer preference, namely: introverted prayer, extraverted prayer, sensing prayer, intuitive prayer, feeling prayer, thinking prayer, judging prayer, and perceiving prayer. On the basis of data provided by 1,476 newly ordained Anglican clergy from England, Ireland, Scotland, and Wales, eight 7-item scales were developed to access these aspects of prayer preferences. Significant correlations were found between each prayer preference and the relevant aspect of psychological type accessed by the Keirsey Temperament Sorter. These data support the theory that psychological type influences the way in which people pray
Global environmental changes: setting priorities for Latin American coastal habitats.
The definitive version is available at www.blackwell-synergy.comThe Intergovernmental Panel for Climate Change (IPCC) reports that Global Environmental Changes (GEC) are occurring quicker than at any other time over the last 25 million years and impacting upon marine environments (Bellard et al., 2012). There is overwhelming evidence showing that GEC are affecting both the quality and quantity of the goods and services provided by a wide range of marine ecosystems. In order to discuss regional preparedness for global environmental changes, a workshop was held in Ilhabela, Brazil (22- 26 April 2012) entitled "Evaluating the Sensitivity of Central and South American Benthic Communities to Global Environmental Changes" that drew together scientists from ten Latin American and three European countries. © 2013 Blackwell Publishing Ltd
Discurso leído ante el claustro de la Universidad Central en el acto de recibir la investidura de doctor en la Facultad de Medicina el 23 de marzo de 1871
Tema: La utilidad de la higiene y necesidad de difundir sus precepto
Municipalidades de Castilla y León : estudio histórico-crítico
Copia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 200
Memorias de la insigne Academia Asnal
Doctor de Ballesteros es seud. de Primo Feliciano Martínez de Ballesteros (Menéndez Pelayo, Htª heterodoxos españoles)Pérez Goyena lo fecha en Pamplona, 1788Álvarez Barrientos lo fecha en Bayona en 1788Sign.: A-M4Port. con esc. real xil
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