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BACKGROUND: This paper will focus on outcome reporting within percutaneous coronary intervention (PCI) trials. A core outcome set (COS) is a standardised set of outcomes that are recommended to be reported in every clinical trial. Using a COS can help to ensure that all relevant outcomes are consistently reported across clinical trials. In 2018, the European Society of Cardiology outlined the only COS published for PCI trials. METHODS: We searched the literature for all randomised controlled trials published between 2014 and 2022. PCI trials included were late-phase trials and must investigate coronary intervention. The primary outcome was the proportion of trials that reported all of the COS-defined outcomes within their publication as either a primary, secondary or safety endpoint. The secondary outcomes included; the number of primary outcomes reported per study, the proportion of studies which use patient and public involvement (PPI) during trial design, outcome variability and outcome consistency. RESULTS: 9580 trials were screened and 115 studies met inclusion/exclusion criteria. Our study demonstrated that 55% (34/62) of PCI trials used a COS when it was available, compared with 40% (21/53) before the availability of a PCI COS set, p=0.121. Fewer primary outcomes were reported after the implementation of the COS, 2 compared with 2.3, p=0.014. There was no difference in the use of PPI between either group. There was a higher level of variability in outcomes reported before the availability of the COS, while the consistency of outcome reporting remained similar. CONCLUSION: The use of a COS in PCI trials is low. This study provides evidence that there still is a lack of awareness of the COS among those who design clinical trials. We also presented the inconsistency and heterogenicity in reporting clinical trial outcomes. Finally, there was a clear lack of PPI utilisation in PCI trials.
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Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/normas , Doença da Artéria Coronariana/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Resultado do Tratamento , Projetos de Pesquisa , Determinação de Ponto Final/normasRESUMO
A new model is presented to predict rubber behavior during chemical aging at fixed strains. The model is validated using a carbon black-filled nitrile butadiene rubber aged in air at 125 °C. The model improves upon Tobolsky's dual network theory, designed for unfilled elastomers undergoing conventional aging but which has also often been used in rubber composites undergoing more complex aging scenarios. This work explores the shortcomings of the original model and demonstrates how the new model overcomes them. The model was validated using uniaxial tensile samples aged at 125 °C for 24-72 h at strains from 0-30%. The permanent set was measured, and the samples were tested on an Instron uniaxial test machine after aging. The cross-link density was estimated by equilibrium swelling. Results show that the new model more accurately models the stress-strain behavior to higher strains and provides more reliable estimates of chain scission and cross-linking after aging.
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INTRODUCTION: A surge in critically ill patients with respiratory failure due to Covid-19 has overwhelmed ICU capacity in many healthcare systems across the world. Given a guarded prognosis and significant resource limitations, less invasive, inventive approaches such as prone positioning (PP) of non-intubated patients with hypoxemic respiratory failure were considered. AIMS AND OBJECTIVES: This is a prospective observational study and the aim is to evaluate the impact of awake PP at the ward level on the oxygenation levels of patients with COVID-19. We also are investigating as secondary outcomes, the risk factors for treatment failure among awake non-intubated patients who tolerated PP compared to those who did not. The primary outcome of this trial is the change in SpO2:FiO2 (SF) ratio from admission to discharge in the participants who tolerated PP compared to those that did not. Secondary outcomes included amongst others are ICU admission rate, in-hospital mortality, and length of stay. METHODS: A total of 63 patients admitted to Beaumont Hospital (BH), Dublin between January and February of 2021 with Covid-19 requiring supplemental oxygen were recruited. RESULTS: A total of 47 (74%) participants were reported as tolerating and 16 (26%) as non-tolerating PP. The mean rank in the primary endpoint in the tolerating group was 38 vs. 16 in the non-tolerating. This was statistically significant (P < 0.001). CONCLUSION: PP was associated with improvements in oxygenation parameters without any reported serious adverse events. A well-designed, randomised control trial, testing the efficacy of PP in non-intubated Covid-19 patients is needed, before the widespread adoption of this practice.
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COVID-19 , Insuficiência Respiratória , Humanos , COVID-19/complicações , COVID-19/terapia , Estudos Prospectivos , Vigília , Decúbito Ventral , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapiaRESUMO
This study aims to increase the pozzolanic reactivity of metakaolin (MK) in Portland cement (PC) blends by adding additional calcium hydroxide (CH_add) to the initial mixture. Cement paste samples were prepared with PC, MK and water with a water-to-binder ratio of 0.6. Cement replacement ratios were chosen from 5 to 40 wt.% MK. For higher replacement ratios, i.e., 20, 30 and 40 wt.% MK, CH_add was included in the mixture. CH_add-to-MK ratios of 0.1, 0.25 and 0.5 were investigated. Thermogravimetric analysis (TGA) was carried out to study the pozzolanic reactivity after 1, 7, 28 and 56 days of hydration. A modified mass balance approach was used to normalize thermogravimetric data and to calculate the calcium hydroxide (CH) consumption of samples with CH_add. Results showed that, without CH_add, a replacement ratio of 30 wt.% or higher results in the complete consumption of CH after 28 days at the latest. In these samples, the pozzolanic reaction of MK turned out to be restricted by the amount of CH available from the cement hydration. The increased amount of CH in the samples with CH_add resulted in an enhanced pozzolanic reaction of MK as confirmed by CH consumption measurements from TGA.