An Engineering Ethics Case Study Review: Petrobras P-36 Accident

In 2001, the world largest oil production in the coast of Brazil was sank due to the series of explosions. This accident claimed 11 lives of crew members and 1 of 4 main support columns affected and lame. The purpose of this case study is to learn from previous experience about the engineering failure from engineering ethics viewpoints which cover the responsible of an engineer to keep safety of people around and maintain of environmental care

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

Background: The EMPA KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods: EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings: Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1). Interpretation: In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding: Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council

Modelling and control analysis of bamboo-based gasification: towards the modern renewable energy

Rapid population growth and expeditious economic development have provided significant influence on the increase of global energy demand. This has contributed to the extreme greenhouse gas emissions and anthropogenic climate change. Innovation in bamboo-based gasification with combined heat and power (BGCHP) system emerges as a potential modern waste-to-energy (WtE) technology to overcome those environmental and energy challenges. In this study, an empirical model is built to evaluate the transient behaviour of BG-CHP system. The empirical model has described the transient variables of a downdraft gasifier equipped with a spark fired internal combustion engine (ICE). A pilot plant dynamic data obtained from the Aspen Dynamic flowsheet model were employed to build a data-driven/empirical model of the gasification based-CHP plant in Simulink, MATLAB. Process control analysis is then conducted based on set point trajectories for 10 h operation via model predictive control (MPC). A control pairing involves syngas flowrate with power output as the manipulated and control variables. A closed-loop analysis revealed that MPC performed well under the intermittent set points 15-18-12-15-20 kW with root mean square error (RSME) of 0.018. The modelling and control results obtained in this study can provide insight into the feasible and flexible operation of a large-scale BG-CHP plant and contribute to the minimization of food and energy competition with the utilization of bamboo as a new-modern energy source

Optimum conditions for the procuction of lopase by alginate-immobilized bacteria

A lipolytic Pseudomonas sp. has been successfully immobilized in strontium alginate gel bead for use in the production of lipase. This paper reports on the various conditions required for its optimum production. A 3% alginate gel concentration with a 20% (w/v) cell loading gives the highest production of lipase. The production of lipase can be enhanced by aeration and shaking but mass transfer effect may be dependent on the ratio of cell mass and bead size. Prolonged recycling with aeration accelerates the rupturing of the beads compared to non-aerated system. A maximum production of lipase is given by 1.5g of immobilized bacteria in 50ml of culture broth. The immobilized bacteria can withstand recycling up to 24 days, (72h cycle), after which time the beads ruptured. The production, however, remains at 70%