206 research outputs found
Evaluating sulfur-tolerance of metal/Ce0.80Gd0.20O1.90 co-impregnated La0.20Sr0.25Ca0.45TiO3 anodes for solid oxide fuel cells
The authors acknowledge funding from the University of St Andrews, HEXIS AG and the EPSRC Grants: EP/M014304/1 âTailoring of Microstructural Evolution in Impregnated SOFC Electrodesâ and EP/L017008/1 âCapital for Great Technologiesâ.The Ni-based cermet Solid Oxide Fuel Cell (SOFC) anode is prone to poisoning by sulfur-based odourising agents, and naturally occurring sulfur species, present in unprocessed natural gas feeds. Next generation SOFC anodes should be able to withstand exposure to these poisons in the event of a malfunction or breakdown of desulfurisation units. Here, we present results pertaining to the sulfur-tolerance of Ni/Ce0.80Gd0.20O1.90 (CGO), Pt/CGO and Rh/CGO co-impregnated La0.20Sr0.25Ca0.45TiO3 anode âbackboneâ microstructures and their ability to recover performance after being exposed to H2S. The Ni/CGO co-impregnated system exhibited severe poisoning by H2S, however, the Rh/CGO system displayed good stability in Area Specific Resistance (ASR) upon introduction of 1â2 ppm of H2S and the Pt/CGO system showed minimal increases in ASR with the addition of 1â8 ppm H2S. Recovery measurements performed in non-humidified H2 at 300 mA cmâ2, after exposure to 8 ppm H2S, indicated that the Pt/CGO and Rh/CGO systems could recover within 10 min, whilst 60 min were required to achieve almost a full recovery of performance for the Ni/CGO system. Additionally, all three impregnate systems showed good stability in operating voltage, after an initial drop, in a fuel gas containing simulated syngas (2:1 H2:CO) with 8 ppm H2S.PostprintPeer reviewe
Priority setting for universal health coverage: We need evidence-informed deliberative processes, not just more evidence on cost-effectiveness
Priority setting of health interventions is generally considered as a valuable approach to support low- and middle-income countries (LMICs) in their strive for universal health coverage (UHC). However, present initiatives on priority setting are mainly geared towards the development of more cost-effectiveness information, and this evidence does not sufficiently support countries to make optimal choices. The reason is that priority setting is in reality a value-laden political process in which multiple criteria beyond cost-effectiveness are important, and stakeholders often justifiably disagree about the relative importance of these criteria. Here, we propose the use of âevidence-informed deliberative processesâ as an approach that does explicitly recognise priority setting as a political process and an intrinsically complex task. In these processes, deliberation between stakeholders is crucial to identify, reflect and learn about the meaning and importance of values, informed by evidence on these values. Such processes then result in the use of a broader range of explicit criteria that can be seen as the product of both international learning (âcoreâ criteria, which include eg, cost-effectiveness, priority to the worse off, and financial protection) and learning among local stakeholders (âcontextualâ criteria). We believe that, with these evidence-informed deliberative processes in place, priority setting can provide a more meaningful contribution to achieving UHC
Employing quality control and feedback to the EQ-5D-5L valuation protocol to improve the quality of data collection
Objectives: In valuing health states using generic questionnaires such as EQ-5D, there are unrevealed issues with the quality of the data collection. The aims were to describe the problems encountered during valuation and to evaluate a quality control report and subsequent retraining of interviewers in improving this valuation. Methods: Data from the first 266 respondents in an EQ-5D-5L valuation study were used. Interviewers were trained and answered questions regarding problems during these initial interviews. Thematic analysis was used, and individual feedback was provided. After completion of 98 interviews, a first quantitative quality control (QC) report was generated, followed by a 1-day retraining program. Subsequently individual feedback was also given on the basis of follow-up QCs. The Wilcoxon signed-rank test was used to assess improvements based on 7 indicators of quality as identified in the first QC and the QC conducted after a further 168 interviews. Results: Interviewers encountered problems in recruiting respondents. Solutions provided were: optimization of the time of interview, the use of broader networks and the use of different scripts to explain the projectâs goals to respondents. For problems in interviewing process, solutions applied were: developing the technical and personal skills of the interviewers and stimulating the respondentsâ thought processes. There were also technical problems related to hardware, software and internet connections. There was an improvement in all 7 indicators of quality after the second QC. Conclusion: Training before and during a study, and individual feedback on the basis of a quantitative QC, can increase the validity of values obtained from generic questionnaires
The routine determination of the endogenous thrombin potential, first results in different forms of hyper- and hypocoagulability
Evidence for scaling up HIV treatment in sub-Saharan Africa: A call for incorporating health system constraints
The Indonesian EQ-5D-5L Value Set
Background: The EQ-5D is one of the most used generic health-related quality-of-life (HRQOL) instruments worldwide. To make the EQ-5D suitable for use in economic evaluations, a societal-based value set is needed. Indonesia does not have such a value set. Objective: The aim of this study was to derive an EQ-5D-5L value set from the Indonesian general population. Methods: A representative sample aged 17Â years and over was recruited from the Indonesian general population. A multi-stage stratified quota method with respect to residence, gender, age, level of education, religion and ethnicity was utilized. Two elicitation techniques, the composite time trade-off (C-TTO) and discrete choice experiments (DCE) were applied. Interviews were undertaken by trained interviewers using computer-assisted face-to-face interviews with the EuroQol Valuation Technology (EQ-VT) platform. To estimate the value set, a hybrid regression model combining C-TTO and DCE data was used. Results: A total of 1054 respondents who completed the interview formed the sample for the analysis. Their characteristics were similar to those of the Indonesian population. Most self-reported health problems were observed in the pain/discomfort dimension (39.66%) and least in the self-care dimension (1.89%). In the value set, the maximum value was 1.000 for full health (health state â11111â) followed by the health state â11112â with value 0.921. The minimum value was â0.865 for the worst state (â55555â). Preference values were most affected by mobility and least by pain/discomfort. Conclusions: We now have a representative EQ-5D-5L value set for Indonesia. We expect our results will promote and facilitate health economic evaluations and HRQOL research in Indonesia
Stable X chromosome reactivation in female human induced pluripotent stem cells
In placental mammals, balanced expression of X-linked genes is accomplished by X chromosome inactivation (XCI) in female cells. In humans, random XCI is initiated early during embryonic development. To investigate whether reprogramming of female human fibroblasts into induced pluripotent stem cells (iPSCs) leads to reactivation of the inactive X chromosome (Xi), we have generated iPSC lines from fibroblasts heterozygous for large X-chromosomal deletions. These fibroblasts show completely skewed XCI of the mutated X chromosome, enabling monitoring of X chromosome reactivation (XCR) and XCI using allele-specific single-cell expression analysis. This approach revealed that XCR is robust under standard culture conditions, but does not prevent reinitiation of XCI, resulting in a mixed population of cells with either two active X chromosomes (Xas) or one Xa and one Xi. This mixed population of XaXa and XaXi cells is stabilized in naive human stem cell medium, allowing expansion of clones with two Xas
The F-BAR protein pacsin2 inhibits asymmetric VE-cadherin internalization from tensile adherens junctions
Vascular homoeostasis, development and disease critically depend on the regulation of endothelial cell-cell junctions. Here we uncover a new role for the F-BAR protein pacsin2 in the control of VE-cadherin-based endothelial adhesion. Pacsin2 concentrates at focal adherens junctions (FAJs) that are experiencing unbalanced actomyosin-based pulling. FAJs move in response to differences in local cytoskeletal geometry and pacsin2 is recruited consistently to the trailing end of fast-moving FAJs via a mechanism that requires an intact F-BAR domain. Photoconversion, photobleaching, immunofluorescence and super-resolution microscopy reveal polarized dynamics, and organization of junctional proteins between the front of FAJs and their trailing ends. Interestingly, pacsin2 recruitment inhibits internalization of the VE-cadherin complex from FAJ trailing ends and is important for endothelial monolayer integrity. Together, these findings reveal a novel junction protective mechanism during polarized trafficking of VE-cadherin, which supports barrier maintenance within dynamic endothelial tissue
The implicitome: A resource for rationalizing gene-disease associations
High-throughput experimental methods such as medical sequencing and genome-wide association studies (GWAS) identify increasingly large numbers of potential relations between genetic variants and diseases. Both biological complexity (millions of potential gene-disease associations) and the accelerating rate of data production necessitate computational approaches to prioritize and rationalize potential gene-disease relations. Here, we use concept profile technology to expose from the biomedical literature both explicitly stated gene-disease relations (the explicitome) and a much larger set of implied gene-disease associations (the implicitome). Implicit relations are largely unknown to, or are even unintended by the original authors, but they vastly extend the reach of existing
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