71 research outputs found

    Bioinspired approaches for toughening of fibre reinforced polymer composites

    Get PDF
    In Nature, there are a large range of tough, strong, lightweight and multifunctional structures that can be an inspiration to better performingmaterials. Thiswork presents a review of structures found in Nature, frombiological ceramics and ceramics composites, biological polymers and polymers composites, biological cellular materials, biological elastomers to functional biological materials, and their main tougheningmechanisms, envisaging potential mimicking approaches that can be applied in advanced continuous fibre reinforced polymer (FRP) composite structures. For this, themost common engineering compositemanufacturing processes and current composite damage mitigation approaches are analysed. This aims at establishing the constraints of biomimetic approaches development as these bioinspired structures are to be manufactured by composite technologies. Combining both Nature approaches and engineering composites developments is a route for the design and manufacturing of high mechanical performance and multifunctional composite structures, therefore new bioinspired solutions are proposed.This research was funded by the project “IAMAT—Introduction of advanced materials technologies into new product development for the mobility industries”, with reference MITP-TB/PFM/0005/2013, under the MIT-Portugal program and in the scope of projects with references UIDB/05256/2020 and UIDP/05256/2020, exclusively financed by FCT - Fundação para a Ciência e Tecnologia

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

    Get PDF
    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Early Cosmetic Results and Midterm Follow-up Findings of Rhinophyma Patients Treated With High-Frequency Electrosurgery and a Discussion on the Severity Assessment of the Disease

    No full text
    Background: Different methods can be used in the surgical treatment of patients with rhinophyma. There are limited numbers of reports on high-frequency electrosurgery treatment. In addition, an efficient scoring system is required to evaluate severity of the disease in clinical progress and recurrence after treatment. Objectives: We evaluated patients with rhinophyma who were treated with high-frequency electrosurgery and discussed the methods used to assess severity of the disease. Methods: Data and photos of 13 patients were retrospectively evaluated and scored via 2 different forms of the rhinophyma severity index. Results: Median rhinophyma severity index scores of patients at first visits were significantly higher than those at second and third visits (P = .002 and P = .002, respectively). Likewise, median modified rhinophyma severity scores of patients at first visits were significantly higher than those at second and third visits (P = .001 and P = .001, respectively). Also, there was a strong positive correlation between these 2 assessment methods (r = 0.838, P < .001). Conclusions: The rhinophyma severity assessment methods used in this study are positively correlated. High-frequency electrosurgery seems to be a procedure that is safe, effective, and relatively cost-effective in the treatment of rhinophyma lesions

    Melt Penetration in Oceanic Lithosphere: Li Isotope Records from the Pozantı-Karsantı Ophiolite in Southern Turkey

    No full text
    Understanding melt penetration in ophiolites is important in revealing the formation and evolution of the oceanic lithosphere, as well as the formation of chromite deposits. We conducted in situ Li isotope analysis of olivine grains from the harzburgite, podiform chromitite and dunite envelope of the mantle sequence, and dunite and wehrlite cumulates from the crustal sequence of the PozantiKarsanti ophiolite. Olivine in the different rocks has variable and distinctive Li concentrations (0.95 to 2.01 ppm) and d 7 Li isotopic compositions (-5.43 to 16.65 &). The olivine in the refractory harzburgite of the Pozanti-Karsanti ophiolite extends from MOR-peridotite-like compositions to lower d 7 Li values and higher Li concentrations, suggesting ingressive Li diffusion via melt penetration. The Li isotopic compositions of the olivine in the dunite envelope and podiform chromitite represent the compositions of their parental melts and thus their sources. The dunite envelope has d 7 Li values beyond MORB and OIB variations and overlaps the arc lava range, suggesting an affinity with arc magmatism. The podiform chromitite, on the other hand, shows wider d 7 Li variation and overall lower values, falling in the ranges of granulite and eclogite. The parental melts of the podiform chromitite might: (1) originate from partial melting of a dehydrated and metamorphosed subducted slab or (2) may initially have had the same isotopic composition as the associated dunite, but later experienced compositional modification by fluids. The Li isotopic compositions of the dunite and wehrlite cumulates fall between the OIB and arc fields, supporting a subduction origin for these ultramafic cumulates and their arc-like parental magmas. The Pozanti-Karsanti ophiolite records various melt penetration agents during its formation and evolution. The melts display progressive compositional variations, mainly between OIB and immature and mature oceanic island arc magmatism, pointing to their correlation with subduction initiation. The distinctive Li isotopic compositions of the Pozanti-Karsanti, Luobusa and Trinity ophiolites suggest that the generation and compositions of penetrating melts in oceanic lithosphere and subsequent formation of chromite deposits are strongly controlled by tectonic setting. Consequently, Li isotope systematics can be used as an indicator of the tectonic setting and mineralization of ophiolites
    corecore