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Conditional Source-term Estimation (CSE) is a combustion model based on the conditional moment hypothesis where transport equations for reactive species are conditionally averaged on conserved scalars. Major advantages of this strategy are the reduced spatial dependence of the conditional averages and negligible fluctuations around the conditional averages, which considerably simplify the reaction rate closure. Historically, simulations using CSE are limited to low carbon fuels (i.e. methane and hydrogen) where the reduced chemistry manifold can be constructed through techniques including intrinsic low dimensional manifolds and trajectory generated manifolds. However, the use of such strategies to create manifolds for diesel surrogates has proven problematic. In this study, the potential of a combination of an unsteady Flamelet Generated Manifold (FGM) and the Conditional Source-term Estimation approach to predict the ignition and flame propagation on an autoigniting n-dodecane spray flame is assessed. Simulations are performed on a single-hole injection of n-dodecane under a wide range of Engine Combustion Network’s “Spray A” conditions within a Reynolds-averaged Navier-Stokes (RANS) framework. Results from parametric sweeps of ambient temperature and oxygen concentration are qualitatively validated against experimental data from the literature and compared against predictions from an industry standard well-stirred reactor model. The efficacy of the CSE-FGM RANS approach in predicting flame characteristics is evaluated and further compared with high fidelity CSE-FGM simulations using the Large Eddy Simulation (LES) turbulence model. Overall, it was found that the CSE-FGM RANS model was able to capture global flame properties — showing particular strength in predicting auto-ignition events in the low temperature region. The model was also able to satisfactorily capture details of the two-stage ignition process. The results were shown to be consistent with those of the CSE-FGM LES model, demonstrating the adaptability of the CSE-FGM approach to different turbulence modelling paradigms.

Aim: We investigated if the baseline value of mid-regional pro-atrial natriuretic peptide (NP), N-terminal pro-B-type NP and copeptin may be helpful in optimizing β-blocker uptitration in elderly patients with heart failure. Patients & methods: According to the biomarkers’ levels, 457 patients were divided into three subgroups and compared with each other at baseline and 3 months after. Results: All mid-regional pro-atrial NP and N-terminal pro-B-type NP subgroups had significant amelioration of left ventricle ejection fraction and New York Heart Association (NYHA) class after 3 months of β-blocker uptitration (p

Aims Beta-blockers (BBs) improve outcomes in heart failure. Results from the Cardiac Insufficiency Bisoprolol Study in Elderly (CIBIS-ELD) trial previously demonstrated the feasibility of heart rate, not maximum dose, as a treatment goal. In this pre-specified analysis, we investigated the prognostic value of achieved heart rate after BB optimization on long-term mortality. Methods and results Elderly heart failure patients from the CIBIS-ELD trial were invited to participate in a follow-up examination 4 years after the initial 12-week BB up-titration period. The relationship between all-cause mortality, BB dose, and heart rate after titration and potentially confounding clinical variables was analysed by multivariable Cox regression. In total, 728 patients (38% women; mean age 72.9 ± 5.4 years) were included. During a mean follow-up period of 45 ± 9 months, 134 patients (19%) died, thus accumulating 2268 patient-years at risk. There was no significant difference in baseline heart rate for survivors and non-survivors (P = 0.19). In models adjusting for age, sex, BB pre-treatment, ventricular function, heart rate, and NYHA class at baseline, a heart rate increase by 10 b.p.m. following up-titration was associated with a subsequent mortality hazard ratio of 1.19 (95% confidence interval 1.02–1.38, P = 0.023). The heart rate range with the lowest mortality and the fewest treatment-related adverse events was 55–64 b.p.m. The achieved BB dose was not associated with mortality risk. Conclusion The heart rate after up-titration, but not BB dose, predicted all-cause mortality risk in elderly patients with chronic heart failure. These patients should be titrated to resting heart rates between 55 and 64 b.p.m.

Aim: To elucidate the prognostic role of procalcitonin (PCT) in patients with acute decompensated heart failure (ADHF) without clinical signs of infection at admission. Materials & Methods: Serial measurements of PCT and NT-proBNP were performed in 168 patients, aged 68 ± 10 years with ADHF followed by 3-month outcome evaluation. Results: Cox regression analysis demonstrated significant predictive value of baseline PCT for all-cause death/hospitalization (area under the curve: 0.67; p = 0.013) at 90th day. The patients with persistently elevated PCT or with an increase during the first 72 h of hospitalization had the worst prognosis (p = 0.0002). Conclusion: Baseline and serial in-hospital measurements of PCT have significant prognostic properties for 3-month all-cause mortality/hospitalization in patients with ADHF without clinical signs of infection at admission.

Background We sought to investigate the effect of beta-blocker (BB) up-titration on serum levels of NT-proBNP and copeptin in patients with heart failure (HF) with reduced (HFREF) or preserved ejection fraction (HFPEF). Methods Serial measurements of NT-proBNP and copeptin were obtained after initiation of BB up-titration in 219 elderly patients with HFREF or HFPEF. Results After initial increasing trend of NT-proBNP at 6 weeks in HFREF patients, there was a subsequent decrease at 12 weeks of BB treatment up-titration (p = 0.003), while no difference was found compared to baseline levels. In contrast to NT-proBNP, there was a continuous decreasing trend of copeptin in HFREF patients (at 12 weeks: p = 0.026). In HFPEF patients, NT-proBNP significantly decreased (p = 0.043) compared to copeptin after 12 weeks of BB up-titration. Conclusions After 12 weeks of BB optimization copeptin might reflect successful up-titration faster than NT-proBNP in HFREF, while the opposite was found in patients with HFPEF.