31,550 research outputs found
Water quality management for domestic rainwater harvesting systems in Fiji
© 2015 IWA Publishing. Health risks from drinking rainwater are relatively small in the developing world context, but action is needed to ensure water safety. Water safety plans (WSPs) use an approach to manage water quality that has shown signs of success with public and communal water supplies, but relatively little research has been done to investigate the application of WSPs to self-supply systems. The aim of this paper is to investigate the primary issues surrounding appropriate water quality management of domestic rainwater harvesting (DRWH) systems in Fiji and consider how the principles of WSPs can be applied in this context. A qualitative research design was followed, utilising semi-structured interviews with 34 rural households and six key informants, sanitary inspections of DRWH systems and thematic data analysis. A number of challenges, including limited government resources and the limited knowledge and casual attitudes of rural rainwater consumers, constrain the practicality of adopting conventional WSPs at the household level, but steps for improvement can be taken
Experimental techniques for ductile damage characterisation
Ductile damage in metallic materials is caused by the nucleation, growth and coalesce of voids and micro-cracks in the metal matrix when it is subjected to plastic strain. A considerable number of models have been proposed to represent ductile failure focusing on the ultimate failure conditions; however, only some of them study in detail the whole damage accumulation process. The aim of this work is to review experimental techniques developed by various authors to measure the accumulation of ductile damage under tensile loads. The measurement methods reviewed include: stiffness degradation, indentation, microstructure analysis, ultrasonic waves propagation, X-ray tomography and electrical potential drop. Stiffness degradation and indentation techniques have been tested on stainless steel 304L hourglass-shaped samples. A special interest is placed in the Continuum Damage Mechanics approach (CDM) as its equations incorporate macroscopic parameters that can represent directly the damage accumulation measured in the experiments. The other main objective lies in identifying the strengths and weaknesses of each technique for the assessment of materials subjected to different strain-rate and temperature conditions
Gene pyramiding as a Bt resistance management strategy: How sustainable is this strategy?
Reports on the emergence of insect resistance to Bacillus thuringiensis delta endotoxins have raiseddoubts on the sustainability of Bt-toxin based pest management technologies. Corporate industry has responded to this challenge with innovations that include gene pyramiding among others. Pyramidingentails stacking multiple genes leading to the simultaneous expression of more than one toxin in a transgenic variety. Questions have been raised on the sustainability of gene pyramiding since the use of insecticide mixtures has shown that cross resistance and/or multiple resistance can render such strategies to be less effective in the long term. Current theoretical and practical evidence in insect population genetics suggest that gene pyramiding cannot be sustained as a resistance management strategy per se. Pyramiding is useful as a strategy to broaden the range of insect pests controlled in each transgenic variety, and it still has to be deployed in tandem with Bt resistance management strategies such as crop refugia, biological pest control, temporal and spatial crop rotations among other
How to Establish and Follow up a Large Prospective Cohort Study in the 21st Century - Lessons from UK COSMOS.
Large-scale prospective cohort studies are invaluable in epidemiology, but they are increasingly difficult and costly to establish and follow-up. More efficient methods for recruitment, data collection and follow-up are essential if such studies are to remain feasible with limited public and research funds. Here, we discuss how these challenges were addressed in the UK COSMOS cohort study where fixed budget and limited time frame necessitated new approaches to consent and recruitment between 2009-2012. Web-based e-consent and data collection should be considered in large scale observational studies, as they offer a streamlined experience which benefits both participants and researchers and save costs. Commercial providers of register and marketing data, smartphones, apps, email, social media, and the internet offer innovative possibilities for identifying, recruiting and following up cohorts. Using examples from UK COSMOS, this article sets out the dos and don'ts for today's cohort studies and provides a guide on how best to take advantage of new technologies and innovative methods to simplify logistics and minimise costs. Thus a more streamlined experience to the benefit of both research participants and researchers becomes achievable
The National Institutes of Health Patient-Reported Outcomes Measurement Information System (PROMIS): a view from the UK.
This is the final version. Available from Dove Medical Press via the DOI in this record.The interest in patient-reported outcome measures (PROMs) continues to increase as recognition of their potential utility rises in an effort to make health systems more patient-centered. The US National Institutes of Health (NIH) Patient-Reported Outcomes Measurement Information System® (PROMIS®) has used state of the art psychometric and statistical techniques to create a universal PROMs language, with potential application across the whole spectrum of health conditions, languages, and geographic locations. PROMIS offers a versatile platform where specific health domains are assessed using both standardized short forms and computerized adaptive tests, which are automatically tailored to individual patients. The scores of each health domain or a standardized profile of multiple domains are all scored on a common metric scale. PROMIS is increasingly recognized as the international gold standard for patient-centered assessment, although the use of these tools in the UK is limited. In this review, the developmental methodology of the PROMIS is described with discussion of its relevant strengths and limitations for use in the UK. We provide a case study of the largest application of the PROMIS tools in the UK as an example of straightforward integration into health-care research. Barriers to the uptake of PROMIS in the UK include the technology requirement, measurement tradition, and lack of a clear understanding of its benefits, and although potential stakeholders should cautiously consider its use, its impressive potential and increasing international utilization should be recognized
Pulsar Results with the Fermi Large Area Telescope
The launch of the Fermi Gamma-ray Space Telescope has heralded a new era in
the study of gamma-ray pulsars. The population of confirmed gamma-ray pulsars
has gone from 6-7 to more than 60, and the superb sensitivity of the Large Area
Telescope (LAT) on Fermi has allowed the detailed study of their spectra and
light curves. Twenty-four of these pulsars were discovered in blind searches of
the gamma-ray data, and twenty-one of these are, at present, radio quiet,
despite deep radio follow-up observations. In addition, millisecond pulsars
have been confirmed as a class of gamma-ray emitters, both individually and
collectively in globular clusters. Recently, radio searches in the direction of
LAT sources with no likely counterparts have been highly productive, leading to
the discovery of a large number of new millisecond pulsars. Taken together,
these discoveries promise a great improvement in the understanding of the
gamma-ray emission properties and Galactic population of pulsars. We summarize
some of the results stemming from these newly-detected pulsars and their timing
and multi-wavelength follow-up observations.Comment: 21 pages, 9 figures, to appear in Proceedings of ICREA Workshop on
The High-Energy Emission from Pulsars and their Systems, Sant Cugat, Spain,
2010 April 12-16 (Springer
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