3,811 research outputs found
Doppler lidar observations of sensible heat flux and intercomparisons with a ground-based energy balance station and WRF model output
This is an open access article - Copyright @ 2009 E. Schweizerbart'sche VerlagsbuchhandlungDuring the Convective and Orographically induced Precipitation Study (COPS), a scanning Doppler lidar was deployed at Achern, Baden-Wüttemberg, Germany from 13th June to 16th August 2007. Vertical velocity profiles ('rays') through the boundary layer were measured every 3 seconds with vertical profiles of horizontal wind velocity being derived from performing azimuth scans every 30 minutes. During Intense Observation Periods radiosondes were launched from the site. In this paper, a case study of convective boundary layer development on 15th July 2007 is investigated. Estimates of eddy dissipation rate are made from the vertically pointing lidar data and used as one input to the velocity-temperature co-variance equation to estimate sensible heat flux. The sensible heat flux values calculated from Doppler lidar data are compared with a surface based energy balance station and output from the Weather Research and Forecasting (WRF) model.Funding is obtained from NER
Quality and acceptability of patient-reported outcome measures used to assess fatigue in axial spondyloarthritis (axSpA): a systematic review (protocol)
BACKGROUND: The prevalence of axial spondyloarthritis (axSpA) is estimated between 0.15 and 1.2%, with many of those patients experiencing severe fatigue. Current axSpA assessment guidance recommends use of a single-item visual analogue scale for fatigue severity. However, concerns have been raised about the ability of such a limited assessment to identify patients with major fatigue, to detect important change in fatigue or to reflect the multi-dimensional nature of fatigue. The proposed systematic review will identify and evaluate the quality and acceptability of single- and multi-item patient-reported outcome measures (PROMs) used to assess fatigue in axSpA, seeking to make recommendations for the ‘best’ measures for research and/or clinical practice.
METHODS/DESIGN: The review will seek to include published studies which report evidence of the development and/or measurement and/or practical properties of clearly defined and reproducible measures of fatigue following completion by patients with axSpA. Five major databases will be searched from 1980 to August 2017: MEDLINE (OVID), EMBASE (OVID), PsycINFO (OVID), World of Science and CINAHL. Study methodological quality will be assessed against the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. The measurement and/or practical properties of reviewed measures will be assessed against current international standards. A short list of the ‘best’-quality PROMs will be produced. The review will be reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
DISCUSSION: This study will provide the first robust and transparent evaluation of patient-reported measures of fatigue used in the axSpA population, synthesising evidence of quality, relevance and acceptability. The review will benefit patients, clinicians, health professionals and researchers wishing to enhance axSpA-fatigue assessment in routine practice, service evaluation and research. The findings will impact future research which seeks to better understand the nature of axSpA fatigue and evaluate the relative benefit of fatigue-management strategies.
SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016042271 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13643-018-0777-7) contains supplementary material, which is available to authorized users
Correspondence: No substantial long-term bias in the Cenozoic benthic foraminifera oxygen-isotope record
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A short-term mouse model that reproduces the immunopathological features of rhinovirus-induced exacerbation of COPD
© 2015 The Author(s). Viral exacerbations of chronic obstructive pulmonary disease (COPD), commonly caused by rhinovirus (RV) infections, are poorly controlled by current therapies. This is due to a lack of understanding of the underlying immunopathological mechanisms. Human studies have identified a number of key immune responses that are associated with RV-induced exacerbations including neutrophilic inflammation, expression of inflammatory cytokines and deficiencies in innate anti-viral interferon. Animal models of COPD exacerbation are required to determine the contribution of these responses to disease pathogenesis. We aimed to develop a short-term mouse model that reproduced the hallmark features of RV-induced exacerbation of COPD. Evaluation of complex protocols involving multiple dose elastase and lipopolysaccharide (LPS) administration combined with RV1B infection showed suppression rather than enhancement of inflammatory parameters compared with control mice infected with RV1B alone. Therefore, these approaches did not accurately model the enhanced inflammation associated with RV infection in patients with COPD compared with healthy subjects. In contrast, a single elastase treatment followed by RV infection led to heightened airway neutrophilic and lymphocytic inflammation, increased expression of tumour necrosis factor (TNF)-α, C-X-C motif chemokine 10 (CXCL10)/IP-10 (interferon γ-induced protein 10) and CCL5 [chemokine (C-C motif) ligand 5]/RANTES (regulated on activation, normal T-cell expressed and secreted), mucus hypersecretion and preliminary evidence for increased airway hyper-responsiveness compared with mice treated with elastase or RV infection alone. In summary, we have developed a new mouse model of RV-induced COPD exacerbation that mimics many of the inflammatory features of human disease. This model, in conjunction with human models of disease, will provide an essential tool for studying disease mechanisms and allow testing of novel therapies with potential to be translated into clinical practice
An insurance value modeling approach that captures the wider value of a novel antimicrobial to health systems, patients, and the population.
Background: Traditional health economic evaluations of antimicrobials currently underestimate their value to wider society. They can be supplemented by additional value elements including insurance value, which captures the value of an antimicrobial in preventing or mitigating impacts of adverse risk events. Despite being commonplace in other sectors, constituents of the impacts and approaches for estimating insurance value have not been investigated. Objectives: This study assessed the insurance value of a novel gram-negative antimicrobial from operational healthcare, wider population health, productivity, and informal care perspectives. Methods: A novel mixed-methods approach was used to model insurance value in the United Kingdom: (1) literature review and multidisciplinary expert workshops to identify risk events for 4 relevant scenarios: ward closures, unavoidable shortage of conventional antimicrobials, viral respiratory pandemics, and catastrophic antimicrobial resistance (AMR); (2) parameterizing mitigable costs and frequencies of risk events across perspectives and scenarios; (3) estimating insurance value through a Monte Carlo simulation model for extreme events and a dynamic disease transmission model. Results: The mean insurance value across all scenarios and perspectives over 10 years in the UK was £718 million, should AMR remain unchanged, where only £134 million related to operational healthcare costs. It would be 50%-70% higher if AMR steadily increased or if a more risk-averse view (1-in-10 year downside) of future events is taken. Discussion: The overall insurance value if AMR remains at current levels (a conservative projection), is over 5 times greater than insurance value from just the operational healthcare costs perspective, traditionally the sole perspective used in health budgeting. Insurance value was generally larger for nationwide or universal (catastrophic AMR, pandemic, and conventional antimicrobial shortages) rather than localized (ward closure) scenarios, across perspectives. Components of this insurance value match previously published estimates of operational costs and mortality impacts. Conclusions: Insurance value of novel antimicrobials can be systematically modeled and substantially augments their traditional health economic value in normal circumstances. These approaches are generalizable to similar health interventions and form a framework for health systems and governments to capture broader value in health technology assessments, improve healthcare access, and increase resilience by planning for adverse scenarios
Australian Enterococcal Sepsis Outcome Programme, 2011
From 1 January to 31 December 2011, 29 institutions around Australia participated in the Australian Enterococcal Sepsis Outcome Programme (AESOP). The aim of AESOP 2011 was to determine the proportion of enterococcal bacteraemia isolates in Australia that are antimicrobial resistant, with particular emphasis on susceptibility to ampicillin and the glycopeptides, and to characterise the molecular epidemiology of the Enterococcus faecalis and E. faecium isolates. Of the 1,079 unique episodes of bacteraemia investigated, 95.8% were caused by either E. faecalis (61.0%) or E. faecium (34.8%). Ampicillin resistance was detected in 90.4% of E. faecium but not detected in E. faecalis. Using Clinical and Laboratory Standards Institute breakpoints (CLSI), vancomycin non-susceptibility was reported in 0.6% and 31.4% of E. faecalis and E. faecium respectively and was predominately due to the acquisition of the vanB operon. Approximately 1 in 6 vanB E. faecium isolates however, had an minimum inhibitory concentration at or below the CLSI vancomycin susceptible breakpoint of ≤ 4 mg/L. Overall, 37% of E. faecium harboured vanA or vanB genes. Although molecular typing identified 126 E. faecalis pulsed-field gel electrophoresis (PFGE) pulsotypes, more than 50% belonged to 2 pulsotypes that were isolated across Australia. E. faecium consisted of 73 PFGE pulsotypes from which 43 multilocus sequence types were identified. Almost 90% of the E. faecium were identified as clonal complex 17 clones, of which approximately half were characterised as sequence type 203, which was isolated Australia-wide. In conclusion, the AESOP 2011 has shown that although polyclonal, enterococcal bacteraemias in Australia are frequently caused by ampicillin-resistant vanB E. faecium
Transplantation of Photoreceptor Precursors Isolated via a Cell Surface Biomarker Panel From Embryonic Stem Cell-Derived Self-Forming Retina.
Loss of photoreceptors due to retinal degeneration is a major cause of untreatable blindness. Cell replacement therapy, using pluripotent stem cell-derived photoreceptor cells, may be a feasible future treatment. Achieving safe and effective cell replacement is critically dependent on the stringent selection and purification of optimal cells for transplantation. Previously, we demonstrated effective transplantation of post-mitotic photoreceptor precursor cells labelled by fluorescent reporter genes. As genetically labelled cells are not desirable for therapy, here we developed a surface biomarker cell selection strategy for application to complex pluripotent stem cell differentiation cultures. We show that a five cell surface biomarker panel CD73(+)CD24(+)CD133(+)CD47(+)CD15(-) facilitates the isolation of photoreceptor precursors from three-dimensional self-forming retina differentiated from mouse embryonic stem cells. Importantly, stem cell-derived cells isolated using the biomarker panel successfully integrate and mature into new rod photoreceptors in the adult mouse retinae after subretinal transplantation. Conversely, unsorted or negatively selected cells do not give rise to newly integrated rods after transplantation. The biomarker panel also removes detrimental proliferating cells prior to transplantation. Notably, we demonstrate how expression of the biomarker panel is conserved in the human retina and propose that a similar selection strategy will facilitate isolation of human transplantation-competent cells for therapeutic application. Stem Cells 2015;33:2469-2482
FSHD: A Repeat Contraction Disease Finally Ready to Expand (Our Understanding of Its Pathogenesis)
Semantic distillation: a method for clustering objects by their contextual specificity
Techniques for data-mining, latent semantic analysis, contextual search of
databases, etc. have long ago been developed by computer scientists working on
information retrieval (IR). Experimental scientists, from all disciplines,
having to analyse large collections of raw experimental data (astronomical,
physical, biological, etc.) have developed powerful methods for their
statistical analysis and for clustering, categorising, and classifying objects.
Finally, physicists have developed a theory of quantum measurement, unifying
the logical, algebraic, and probabilistic aspects of queries into a single
formalism. The purpose of this paper is twofold: first to show that when
formulated at an abstract level, problems from IR, from statistical data
analysis, and from physical measurement theories are very similar and hence can
profitably be cross-fertilised, and, secondly, to propose a novel method of
fuzzy hierarchical clustering, termed \textit{semantic distillation} --
strongly inspired from the theory of quantum measurement --, we developed to
analyse raw data coming from various types of experiments on DNA arrays. We
illustrate the method by analysing DNA arrays experiments and clustering the
genes of the array according to their specificity.Comment: Accepted for publication in Studies in Computational Intelligence,
Springer-Verla
Time Variability of Molecular Line Emission in IRC+10216
We present the results of monitoring the molecular emission of the C-rich AGB star IRC+10216 over 3 years with the Herschel Space Observatory. Observations of rotational transitions of various vibrational levels of CO, 13CO, CS, CCH, H2O, SiO, SiS, SiC2, HCN and HNC have been collected with the HIFI, PACS and SPIRE instruments over multiple epochs. The intensity monitoring shows strong and periodic variations of most of the observed molecules, often with differential behavior depending on the transition level (larger variation at higher J), and generally enhanced modulations in the vibrational modes of some of these molecules (e.g. HCN). These results show that the effect of IR pumping through the different vibrational levels on the emergent line profiles of a given transition can be really significant. This implies that the IR radiation field of the circumstellar envelope and its time variation has to be taken into account in any radiative transfer model in order to derive accurately the physico-chemical structure of the envelope
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