9 research outputs found
Supercritical Water Gasification of Eucalyptus Wood Chips Using NiFe2O4 as a Catalyst
In this work, the supercritical water gasification of eucalyptus wood chips has been investigated in relation to reaction temperature and presence of catalyst. Experiments were performed in a batch reactor at 450 ÂșC and 500 ÂșC with two different feed concentrations. This work wanted to evaluate mainly the gases were formed during the reactions. The gas products were analysed by gas chromatography. According to the results, it was found that eucalyptus wood chips reacted to form mainly H2, CH4 gases with little yield of CO2. Increasing the reaction temperature beyond 500 ÂșC led to the increasing production of both CH4 (around 31.1 mol%) and H2 (up to 38 mol%) gases and the liquid sample and solid residue have decreased. Generally, this work suggests that the SCWG has improved significantly the production of H2 but more experiments still necessary to verify the effects of other experimental parameters and to characterise the liquid sample and solid residue
Catalytic Properties and Recycling of NiFe 2 O 4 Catalyst for Hydrogen Production by Supercritical Water Gasification of Eucalyptus Wood Chips
Nickel iron oxide (NiFe2O4) catalyst was prepared by the combustion reaction method and characterized by XRD, N2 adsorption/desorption, thermogravimetric analysis (TG), and temperature programmed reduction (TPR). The catalyst presented a mixture of oxides, including the NiFe2O4 spinel and specific surface area of 32.4 m2 gâ1. The effect of NiFe2O4 catalyst on the supercritical water gasification (SCWG) of eucalyptus wood chips was studied in a batch reactor at 450 and 500 °C without catalyst and with 1.0 g and 2.0 g of catalyst and 2.0 g of biomass for 60 min. In addition, the recyclability of the catalyst under the operating conditions was also tested using recovered and recalcined catalysts over three reaction cycles. The highest amount of H2 was 25 mol% obtained at 450 °C, using 2 g of NiFe2O4 catalyst. The H2 mol% was enhanced by 45% when compared to the non-catalytic test, showing the catalytic activity of NiFe2O4 catalyst in the WGS and the steam reforming reactions. After the third reaction cycle, the results of XRD demonstrated formation of coke which caused the deactivation of the NiFe2O4 and consequently, a 13.6% reduction in H2 mol% and a 5.6% reduction in biomass conversion
A IMPORTĂNCIA DA CLASSIFICAĂĂO DE RISCO NOS SERVIĂOS DE URGĂNCIA E EMERGĂNCIA
Objective: To discuss the importance of risk classification in urgent and emergency care through the existing literature. Methods: This is a qualitative integrative literature review. The search for works involved in the research was carried out in the following databases: SCIELO, LILACS, BDENF and MEDLINE, using the health sciences descriptors: "Hospice care", "Palliative care" and "Intensive care unit". The inclusion criteria were: published between 2013 and 2023, with free access to full texts, articles in Portuguese, English and Spanish and related to the theme. Exclusion criteria were: duplicate articles, incomplete articles, abstracts, reviews, debates, articles published in event proceedings and unavailable in full. Results: When risk classification is applied, there is integration between various organizational services so that patients' health needs can be resolved in a shorter time and properly applied. Conclusion: It can be concluded that risk classification used effectively in emergency services favors quality care, as well as assertiveness when it comes to stratifying each case and knowing which priority to allocate the patient to.Objetivo: Discutir por meio da literatura existente acerca da importĂąncia da classificação de risco nos serviços de urgĂȘncia e emergĂȘncia. MĂ©todos: Trata-se de uma revisĂŁo integrativa da literatura de carĂĄter qualitativo. A busca dos trabalhos envolvidos na pesquisa foi realizada nas seguintes bases de dados: SCIELO, LILACS, BDENF e MEDLINE, a partir dos descritores em ciĂȘncias da saĂșde: âAssistĂȘncia hospitalarâ, âCuidados paliativosâ e âUnidade de terapia intensivaâ. Os critĂ©rios de inclusĂŁo foram: publicados no perĂodo entre 2013 e 2023, cujo acesso ao periĂłdico era livre aos textos completos, artigos em idioma portuguĂȘs, inglĂȘs e espanhol e relacionados a temĂĄtica. CritĂ©rios de exclusĂŁo foram: artigos duplicados, incompletos, resumos, resenhas, debates, artigos publicados em anais de eventos e indisponĂveis na Ăntegra. Resultados: Na aplicação da classificação de risco hĂĄ integração entre diversos serviços de organização para que se tenha resolutividade da necessidade de saĂșde dos pacientes em um tempo menor e uma aplicação adequada. ConclusĂŁo: Conclui-se que a classificação de risco usada de forma efetiva nos serviços de emergĂȘncia favorece para um atendimento de qualidade, assim como assertividade no momento de estratificar cada caso e saber em qual prioridade alocar esse paciente
Supercritical Water Gasification of Eucalyptus Wood Chips Using NiFe
In this work, the supercritical water gasification of eucalyptus wood chips has been investigated in relation to reaction temperature and presence of catalyst. Experiments were performed in a batch reactor at 450 ÂșC and 500 ÂșC with two different feed concentrations. This work wanted to evaluate mainly the gases were formed during the reactions. The gas products were analysed by gas chromatography. According to the results, it was found that eucalyptus wood chips reacted to form mainly H2, CH4 gases with little yield of CO2. Increasing the reaction temperature beyond 500 ÂșC led to the increasing production of both CH4 (around 31.1 mol%) and H2 (up to 38 mol%) gases and the liquid sample and solid residue have decreased. Generally, this work suggests that the SCWG has improved significantly the production of H2 but more experiments still necessary to verify the effects of other experimental parameters and to characterise the liquid sample and solid residue
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Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study
We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05â1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4â7 days or â„ 8 days of 1.25 (1.04â1.48), p = 0.015 and 1.31 (1.11â1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05â1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4â7 days or â„ 8 days of 1.25 (1.04â1.48), p = 0.015 and 1.31 (1.11â1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care
Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study
Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries
Background
Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks.
Methods
The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned.
Results
A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31).
Conclusion
Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)