27 research outputs found

    Relating moisture ingress to component strength and stiffness for carbon-fibre composites.

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    Moisture diffusion studies were performed using unidirectional (UD) tape and quasiisotropic (QI) woven 5-harness satin fabric, carbon fibre reinforced (CFR) epoxy composite materials. Firstly the moisture constants, (i.e. diffusion coefficient, D[x], and equilibrium moisture content, M[max]) were experimentally derived at 70°C and 85% relative humidity (%RH), for the two CFR materials. To investigate moisture absorption as a function of %RH test coupons were conditioned to differing equilibrium moisture levels viz., 70°C/60%RH, 70°C/75%RH, 70°C/85%RH, and 70°C/95%RH. Also oven dry (OD) and as-received (AR) tests were performed for baseline comparison. The effect of moisture absorption on the mechanical behaviour was investigated; lamina properties were studied by measuring tension, compression, shear (inter/intralaminar) strength and stiffness of the UD material. This comprehensive set of testing provided quantitative relationships between moisture content and mechanical properties. The quasi-isotropic lay-up was then utilised to investigate multi-directional laminate lay-ups using open hole tension and compression testing. The experimental data showed that the uptake of moisture in both the materials studied was described well by Fick's Second Law and the properties most affected by moisture ingress were matrix-dominated properties. More specifically, the transverse tensile strength, F[t][2] was most affected by the ingress of moisture, with a near 50% reduction in strength when conditioned to equilibrium moisture content at 70°C/95%RH. Such information is a necessary prerequisite if improved design procedures are going to be developed in the future. The initial phase of testing produced mechanical property/moisture relationships that were employed to predict the strength and stiffness of the material containing specific moisture gradients through-the-thickness (TTT). To be able to predict mechanical properties with different moisture distribution, firstly moisture distribution TTT of the material was modelled using an analytical solution to Fick's Second Law. Then moisture content was considered on a ply-by-ply basis TTT of the laminate; reductions were applied to each individual ply property dependent on the moisture content using the experimentally derived relationships, essentially applying environmental knock-down factors (KEKDF'S) to each individual ply. Classical Laminate Analysis (CLA) was then performed using the Max Stress failure criteria in order to predict the overall laminate failure. A second phase of mechanical testing was then performed to validate these predictions. The mechanical property predictions compared well to the experimental data showing similar reductions in strength for a given profile of moisture in the laminate. The predicted strengths also fell within the measured standard deviation of the experimental data in a significant proportion of the results

    Children must be protected from the tobacco industry's marketing tactics.

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    The James Webb Space Telescope Mission

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    Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4m4m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5m6.5m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

    Trust in the Transplant Team Associated With the Level of Chronic Illness Management—A Secondary Data Analysis of the International BRIGHT Study

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    A trustful relationship between transplant patients and their transplant team (interpersonal trust) is essential in order to achieve positive health outcomes and behaviors. We aimed to 1) explore variability of trust in transplant teams; 2) explore the association between the level of chronic illness management and trust; 3) investigate the relationship of trust on behavioral outcomes. A secondary data analysis of the BRIGHT study (ID: NCT01608477; https://clinicaltrials.gov/ct2/show/NCT01608477?id=NCT01608477&rank=1) was conducted, including multicenter data from 36 heart transplant centers from 11 countries across four different continents. A total of 1,397 heart transplant recipients and 100 clinicians were enrolled. Trust significantly varied among the transplant centers. Higher levels of chronic illness management were significantly associated with greater trust in the transplant team (patients: AOR= 1.85, 95% CI = 1.47–2.33, p < 0.001; clinicians: AOR = 1.35, 95% CI = 1.07–1.71, p = 0.012). Consultation time significantly moderated the relationship between chronic illness management levels and trust only when clinicians spent ≥30 min with patients. Trust was significantly associated with better diet adherence (OR = 1.34, 95%CI = 1.01–1.77, p = 0.040). Findings indicate the relevance of trust and chronic illness management in the transplant ecosystem to achieve improved transplant outcomes. Thus, further investment in re-engineering of transplant follow-up toward chronic illness management, and sufficient time for consultations is required

    Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

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    BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

    Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

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    Introduction: The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. Methods: In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. Findings: Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. Interpretation: After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification

    The MET Inhibitor AZD6094 (Savolitinib, HMPL-504) induces regression in papillary renal cell carcinoma patient-derived xenograft models

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    Papillary renal cell carcinoma (PRCC) is the second most common cancer of the kidney and carries a poor prognosis for patients with nonlocalized disease. The HGF receptor MET plays a central role in PRCC and aberrations, either through mutation, copy number gain, or trisomy of chromosome 7 occurring in the majority of cases. The development of effective therapies in PRCC has been hampered in part by a lack of available preclinical models. We determined the pharmacodynamic and antitumor response of the selective MET inhibitor AZD6094 in two PRCC patient-derived xenograft (PDX) models

    Practice patterns to improve pre and post-transplant medication adherence in heart transplant centres: a secondary data analysis of the international BRIGHT study.

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    BACKGROUND: As medication non-adherence is a major risk factor for poor post-transplant outcomes, we explored how adherence is assessed, enhanced and integrated across the transplant continuum. AIM: The aim of this study was to study practice patterns regarding pre- and post-transplant medication adherence assessment and interventions in international heart transplant centres. METHODS: We used data from the Building Research Initiative Group: chronic illness management and adherence in heart transplantation (BRIGHT) study, a cross-sectional study conducted in 36 heart transplant centres in 11 countries. On a 27-item questionnaire, 100 clinicians (range one to five per centre) reported their practice patterns regarding adherence assessment and intervention strategies pre-transplant, immediately post-transplant, less than one year, and one or more year post-transplant. Educational/cognitive, counselling/behavioural and psychosocial/affective strategies were assessed. Clinicians' responses (intervention present vs. absent; or incongruence in reporting intervention) were aggregated at the centre level. RESULTS: The adherence assessment method most commonly used along the transplant continuum was questioning patients (range 75-88.9%). Pre-transplant, all three categories of intervention strategy were applied. Providing reading materials (82.9%) or instructions (68.6%), involving family or support persons in education (91.4%), and establishing partnership (91.4%) were used most frequently. Post-transplant, strategies closely resembled those employed pre-transplant. Training patients (during recovery) and cueing were more often applied during hospitalisation (74.3%). After the first year post-transplant, except for motivational interviewing (25.7-28.6%), the number of strategies decreased. CONCLUSIONS: Across the transplant continuum, diverse adherence interventions are implemented; however, post-transplant, the frequency of adherence interventions decreases. Therefore, increased investment is necessary in long-term adherence interventions

    Prevalence of Medication Nonadherence to co-medication Compared to immunosuppressants in Heart Transplant Recipients: Findings From the International Cross-sectional BRIGHT Study

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    Purpose: To assess and compare the prevalence of medication nonadherence (MNA) (implementation and persistence) to immunosuppressants and co-medications in heart transplant recipients.Methods: MNA prevalence was assessed using the Basel Assessment of Adherence to Immunosuppressive Medications Scale (self-report) and compared using logistic regression in a 4-continent sample of 1397 heart transplant recipients from 36 heart transplant centers in 11 countries.Findings: MNA was significantly (alpha = 0.05) higher to co-medications than to immunosuppressants (taking nonadherence: 23.9% vs 17.3%; odds ratio [OR] = 1.5; 95% CI, 1.30-1.73; drug holiday: 5.7% vs 1.9%; OR = 3.17; 95% CI, 2.13-4.73; dose alteration: 3.8% vs 1.6%; OR = 2.46; 95% CI, 1.49-4.06; and discontinuation: 2.6% vs 0.5%; OR = 5.15; 95% CI, 2.36-11.20). (C) 2018 Elsevier Inc. All rights reserved

    Prevalence of Medication Nonadherence to Co-medication Compared to Immunosuppressants in Heart Transplant Recipients: Findings From the International Cross-sectional BRIGHT Study

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    PURPOSE: To assess and compare the prevalence of medication nonadherence (MNA) (implementation and persistence) to immunosuppressants and co-medications in heart transplant recipients. METHODS: MNA prevalence was assessed using the Basel Assessment of Adherence to Immunosuppressive Medications Scale (self-report) and compared using logistic regression in a 4-continent sample of 1397 heart transplant recipients from 36 heart transplant centers in 11 countries. FINDINGS: MNA was significantly (α = 0.05) higher to co-medications than to immunosuppressants (taking nonadherence: 23.9% vs 17.3%; odds ratio [OR] = 1.5; 95% CI, 1.30-1.73; drug holiday: 5.7% vs 1.9%; OR = 3.17; 95% CI, 2.13-4.73; dose alteration: 3.8% vs 1.6%; OR = 2.46; 95% CI, 1.49-4.06; and discontinuation: 2.6% vs 0.5%; OR = 5.15; 95% CI, 2.36-11.20). IMPLICATIONS: The observed MNA necessitates adherence-enhancing interventions encompassing the entire post-heart transplant medication regimen. ClinicalTrials.gov identifier: NCT01608477.status: publishe
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