The Egyptian Cardiothoracic Surgeon (ECTS - E-Journal)
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Selective Hysteretic Sorption of Light Hydrocarbons in a Flexible Metal-Organic Framework Material
No full textPorous MFM-202a (MFM = Manchester Framework Material, replacing the NOTT designation) shows an exceptionally high uptake of acetylene, 18.3 mmol g–1 (47.6 wt %) at 195 K and 1.0 bar, representing the highest value reported to date for a framework material. However, at 293 K and 10 bar C2H6 uptake (9.13 mmol g–1) is preferred. Dual-site Langmuir-Freundlich (DSLF)- and Numerical Integration (NI)-based IAST methods have been used to analyze selectivities for C1 to C3 hydrocarbons. MFM-202a exhibits broadly hysteretic desorption of acetylene; such behavior is important for practical gas storage since it allows the gas to be adsorbed at high pressure but stored at relatively low pressure. Stepwise uptake and hysteretic release were also observed for adsorption of other unsaturated light hydrocarbons (ethane and propene) in MFM-202a but not for saturated hydrocarbons (methane, ethane, and propane). MFM-202a has been studied by in situ synchrotron X-ray powder diffraction to reveal the possible phase transition of the framework host as a function of gas loading. A comprehensive analysis for the selectivities between these light hydrocarbons has been conducted using both IAST calculation and dual-component mixed-gas adsorption experiments, and excellent agreement between theory and experiment was achieved
Using action research to enhance learning on end-use energy demand: lessons from reflective practice
No full textThis paper responds to the need for a greater integration of energy and environment themes in the higher education curriculum. We explore the practical implications of empowering students towards the implementation of individual action research projects focused on investigating and addressing insufficient or wasteful energy consumption among households and businesses. The paper scrutinizes a series of teaching and assessment activities within this domain, undertaken during 6 consecutive academic years – between 2008 and 2013 – within a third-level undergraduate course unit at the University of Birmingham in the United Kingdom. Using questionnaire surveys, assessed projects and interviews with the students, we have found evidence to suggest that the action research projects contributed to the emergence of constructive alignment in the entire teaching process, while opening the space for informal action learning ‘sets’ leading to the generation of new problem-solving skills useful in the job market
Multi-channel registration of fractional anisotropy and T1-weighted images in the presence of atrophy: application to multiple sclerosis
No full textCo-registration of structural T1-weighted (T1w) scans and diffusion tensor imaging (DTI)-derived fractional anisotropy (FA) maps to a common space is of particular interest in neuroimaging, as T1w scans can be used for brain segmentation while DTI can provide microstructural tissue information. While the effect of lesions on registration has been tackled and solutions are available, the issue of atrophy is still open to discussion. Multi-channel (MC) registration algorithms have the advantage of maintaining anatomical correspondence between different contrast images after registration to any target space. In this work, we test the performance of an MC registration approach applied to T1w and FA data using simulated brain atrophy images. Experimental results are compared with a standard single-channel registration approach. Multi-channel registration of fractional anisotropy and T1-weighted images in the presence of atrophy: application to multiple sclerosis Both qualitative and quantitative evaluations are presented, showing that the MC approach provides better alignment with the target while maintaining better T1w and FA co-alignment
The Thermal Evolution of H Chondrites as Revealed by the I-Xe Chronometer
No full textI-Xe data indicate cooling of the H chondrite parent body was more complicated than can be accounted for by the onion-shell model
A case of relapsing and refractory catastrophic anti-phospholipid syndrome successfully managed with eculizumab, a complement 5 inhibitor.
No full textCharacteristics of lesional and extra-lesional cortical grey matter in relapsing-remitting and secondary progressive multiple sclerosis: A magnetisation transfer and diffusion tensor imaging study.
No full textBACKGROUND: In multiple sclerosis (MS), diffusion tensor and magnetisation transfer imaging are both abnormal in lesional and extra-lesional cortical grey matter, but differences between clinical subtypes and associations with clinical outcomes have only been partly assessed. OBJECTIVE: To compare mean diffusivity, fractional anisotropy and magnetisation transfer ratio (MTR) in cortical grey matter lesions (detected using phase-sensitive inversion recovery (PSIR) imaging) and extra-lesional cortical grey matter, and assess associations with disability in relapse-onset MS. METHODS: Seventy-two people with MS (46 relapsing-remitting (RR), 26 secondary progressive (SP)) and 36 healthy controls were included in this study. MTR, mean diffusivity and fractional anisotropy were measured in lesional and extra-lesional cortical grey matter. RESULTS: Mean fractional anisotropy was higher and MTR lower in lesional compared with extra-lesional cortical grey matter. In extra-lesional cortical grey matter mean fractional anisotropy and MTR were lower, and mean diffusivity was higher in the MS group compared with controls. Mean MTR was lower and mean diffusivity was higher in lesional and extra-lesional cortical grey matter in SPMS when compared with RRMS. These differences were independent of disease duration. In multivariate analyses, MTR in extra-lesional more so than lesional cortical grey matter was associated with disability. CONCLUSION: Magnetic resonance abnormalities in lesional and extra-lesional cortical grey matter are greater in SPMS than RRMS. Changes in extra-lesional compared with lesional cortical grey matter are more consistently associated with disability
Flood resilience technology in Europe: identifying barriers and co-producing best practice (in Press)
No full textDepression predicts future emergency hospital admissions in primary care patients with long-term physical illness: A cohort study
No full textObjectiveMore than 15 million people currently suffer from a chronic physical illness in England. The objective of this study was to determine whether depression is independently associated with prospective emergency hospital admission in patients with chronic physical illness.Method1860 primary care patients in socially deprived areas of Manchester with at least one of four exemplar chronic physical conditions completed a questionnaire about physical and mental health, including a measure of depression. Emergency hospital admissions were recorded using GP records for the year before and the year following completion of the questionnaire.ResultsThe numbers of patients who had at least one emergency admission in the year before and the year after completion of the questionnaire were 221/1411 (15.7%) and 234/1398 (16.7%) respectively. The following factors were independently associated with an increased risk of prospective emergency admission to hospital: having no partner (OR 1.49, 95% CI 1.04 to 2.15); having ischaemic heart disease (OR 1.60, 95% CI 1.04 to 2.46); having a threatening experience (OR 1.16, 95% CI 1.04 to 1.29); depression (OR 1.58, 95% CI 1.04 to 2.40); and emergency hospital admission in the year prior to questionnaire completion (OR 3.41, 95% CI 1.98 to 5.86).ConclusionTo prevent potentially avoidable emergency hospital admissions, greater efforts should be made to detect and treat co-morbid depression in people with chronic physical illness in primary care, with a particular focus on patients who have no partner, have experienced threatening life events, and have had a recent emergency hospital admission
Modelling conditions and health care processes in electronic health records: an application to severe mental illness with the Clinical Practice Research Datalink.
No full textBackgroundThe use of Electronic Health Records databases for medical research has become mainstream. In the UK, increasing use of Primary Care Databases is largely driven by almost complete computerisation and uniform standards within the National Health Service. Electronic Health Records research often begins with the development of a list of clinical codes with which to identify cases with a specific condition. We present a methodology and accompanying Stata and R commands (pcdsearch/Rpcdsearch) to help researchers in this task. We present severe mental illness as an example.MethodsWe used the Clinical Practice Research Datalink, a UK Primary Care Database in which clinical information is largely organised using Read codes, a hierarchical clinical coding system. Pcdsearch is used to identify potentially relevant clinical codes and/or product codes from word-stubs and code-stubs suggested by clinicians. The returned code-lists are reviewed and codes relevant to the condition of interest are selected. The final code-list is then used to identify patients.ResultsWe identified 270 Read codes linked to SMI and used them to identify cases in the database. We observed that our approach identified cases that would have been missed with a simpler approach using SMI registers defined within the UK Quality and Outcomes Framework.ConclusionWe described a framework for researchers of Electronic Health Records databases, for identifying patients with a particular condition or matching certain clinical criteria. The method is invariant to coding system or database and can be used with SNOMED CT, ICD or other medical classification code-lists
Design and analysis of trials with a partially nested design and a binary outcome measure.
No full textWhere treatments are administered to groups of patients or delivered by therapists, outcomes for patients in the same group or treated by the same therapist may be more similar, leading to clustering. Trials of such treatments should take account of this effect. Where such a treatment is compared with an un-clustered treatment, the trial has a partially nested design. This paper compares statistical methods for this design where the outcome is binary. Investigation of consistency reveals that a random coefficient model with a random effect for group or therapist is not consistent with other methods for a null treatment effect, and so this model is not recommended for this design. Small sample performance of a cluster-adjusted test of proportions, a summary measures test and logistic generalised estimating equations and random intercept models are investigated through simulation. The expected treatment effect is biased for the logistic models. Empirical test size of two-sided tests is raised only slightly, but there are substantial biases for one-sided tests. Three formulae are proposed for calculating sample size and power based on (i) the difference of proportions, (ii) the log-odds ratio or (iii) the arc-sine transformation of proportions. Calculated power from these formulae is compared with empirical power from a simulations study. Logistic models appeared to perform better than those based on proportions with the likelihood ratio test performing best in the range of scenarios considered. For these analyses, the log-odds ratio method of calculation of power gave an approximate lower limit for empirical power. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd