Thermoeconomic and exergo environmental sustainability of a power-cooling organic Rankine cycle with ejector system

The study presents a power-cooling organic Rankine cycle with an ejector system (ORCPCES). The objective is to determine the thermodynamic, economic and sustainability of the ORCPCES from the manufacturing, commissioning and decommissioning phases. Component-wise modelling was first performed based on the exergy concept. The system simulation was carried out using a developed source code in Engineering Equation Solver (EES). The refrigerant leakages and the material component impact on the environment were evaluated at all phases of the plant life cycle. The results indicate that the evaporator cooling rate (ECR) and the power-cooling efficiency (PCE) varied from 120.8 to 153 kW and 28.87 to 34.43 % across the refrigerants with the highest PCE and exergy efficiency obtained using R1234ze. The maximum power output was obtained using R1234ze. The overall environmental impact due to the components occurred at, and for R245fa, R1234yf, and R1234ze, respectively, while and was due to the working fluids in that order. The unit cost of electricity (UCOE) across the refrigerants varies from 0.181$/kWh to 0.2291$/kWh with the least UCOE, 0.181$/kWh obtained using R1234ze. The highest exergetic sustainability index of 0.56 was achieved using R1234ze

Thermoeconomic and exergoenvironmental sustainability of a power-cooling organic Rankine cycle with ejector system

The study presents a power-cooling organic Rankine cycle with an ejector system (ORCPCES). The objective is to determine the thermodynamic, economic and sustainability of the ORCPCES from the manufacturing, commissioning and decommissioning phases. Component-wise modelling was first performed based on the exergy concept. The system simulation was carried out using a developed source code in Engineering Equation Solver (EES). The refrigerant leakages and the material component impact on the environment were evaluated at all phases of the plant life cycle. The results indicate that the evaporator cooling rate (ECR) and the power-cooling efficiency (PCE) varied from 120.8 to 153 kW and 28.87 to 34.43 % across the refrigerants with the highest PCE and exergy efficiency obtained using R1234ze. The maximum power output was obtained using R1234ze. The overall environmental impact due to the components occurred at, and for R245fa, R1234yf, and R1234ze, respectively, while and was due to the working fluids in that order. The unit cost of electricity (UCOE) across the refrigerants varies from 0.181$/kWh to 0.2291$/kWh with the least UCOE, 0.181$/kWh obtained using R1234ze. The highest exergetic sustainability index of 0.56 was achieved using R1234ze

Progress and challenges of demand-led co-produced sub-seasonal-to-seasonal (S2S) climate forecasts in Nigeria

This paper identifies fundamental issues which prevent the effective uptake of climate information services in Nigeria. We propose solutions which involve the extension of short-range (1 to 5 days) forecasts beyond that of medium-range (7 to 15 days) timescales through the operational use of current forecast data as well as improve collaboration and communication with forecast users. Using newly available data to provide seamless operational forecasts from short-term to sub-seasonal timescales, we examine evidence to determine if effective demand-led sub-seasonal-to-seasonal (S2S) climate forecasts can be co-produced. This evidence involves: itemization of forecast products delivered to stakeholders, with their development methodology; enumeration of inferences of forecast products and their influences on decisions taken by stakeholders; user-focused discussions of improvements on co-produced products; and the methods of evaluating the performance of the forecast products. We find that extending the production pipeline of short-range forecast timescales beyond the medium-range, such that the medium-range forecast timescales can be fed into existing tools for applying short-range forecasts, assisted in mitigating the risks of sub-seasonal climate variability on socio-economic activities in Nigeria. We also find that enhancing of collaboration and communication channels between the producers and the forecast product users helps to: enhance the development of user-tailored impact-based forecasts; increases users’ trusts in the forecasts; and, seamlessly improves forecast evaluations. In general, these measures lead to more smooth delivery and increase in uptake of climate information services in Nigeria

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Additional file 1 of Development of eco-friendly brake pads using industrial and agro-waste materials

Additional file 1

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine