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To simulate turbulent flames with high accuracy at low computational cost, Rieth et al. ["A hybrid flamelet finite-rate chemistry approach for efficient LES with a transported FDF," Combust. Flame 199, 183–193 (2019)] have developed a hybrid method combining a combustion sub-grid model with assumed filtered density function (FDF) with a transported FDF approach. The present paper extends the hybrid approach to a stratified flame from the Cambridge stratified flame series. In contrast to the conventional Lagrangian FDF transport approach, the hybrid model applies Lagrangian particles to solve FDF transport only in selected regions, while an assumed FDF is applied in the remaining domain. With the hybrid model, the overall number of particles is strongly reduced compared to the conventional Lagrangian FDF transport model, promising great savings in computational cost. To provide a basis for the comparisons, simulations with assumed FDF or transported FDF only have also been performed. The present work aims to show the advantage of the Lagrangian transported FDF and the hybrid approach for a highly stratified flame, one of the most challenging members of the well-known Cambridge stratified flame series. Different criteria are tested for triggering the switch-over between the methods to maximize the efficiency of the hybrid approach, where basic flame quantities such as mixture fraction were predicted well with the assumed FDF model, and the temperature and mass fraction of carbon monoxide were predicted better by the hybrid method, featuring the transported FDF technique. [ABSTRACT FROM AUTHOR]

What is known and objective There are a few Korean studies on the economics of statins based on reduction in low-density lipoprotein cholesterol ( LDL-C) data from other countries. This study aimed to analyse and compare the cost-effectiveness of statins according to the baseline LDL-C level in Korea. Methods Between January 2009 and December 2015, the data of patients who were prescribed statins for the first time were extracted from electronic medical records. We performed a cost-effectiveness analysis ( CEA) based on the LDL-C reduction rate ( CEA- RR) and target achievement rate. Results and discussion Among high-intensity statins, the CEA- RR value of rosuvastatin (20 mg) was significantly lower than that of atorvastatin (40 mg) at all baseline LDL-C levels, except levels of 160-189 mg/ dL. Additionally, at baseline LDL-C levels of 130-159 mg/ dL, the CEA- RR value of rosuvastatin (20 mg) was three times lower than that of atorvastatin (40 mg) (9·1 ± 2·5 $/% vs. 31·7 ± 15·0 $/%, P < 0·001). Among moderate-to-low-intensity statins, rosuvastatin (5 mg) showed the lowest CEA- RR value (4·0 ± 0·6 $/%), and the value significantly increased for pitavastatin (2 mg) (8·0 ± 0·6 $/%), atorvastatin (10 mg) (9·5 ± 0·5 $/%), simvastatin (10·8 ± 1·1 $/%) and pravastatin (40 mg) (11·5 ± 0·9 $/%) in order ( P < 0·0001). On changing from atorvastatin (10 mg) to atorvastatin (20 mg), the additional yearly cost was 16·0 and additional CEA- RR value was 2·74 $/%. On the other hand, on changing from atorvastatin (10 mg) to rosuvastatin (10 mg), the additional yearly cost was −16·3 and additional CEA- RR value was −1·8 $ /%. What is new and conclusion We successfully compared the cost-effectiveness of statins according to the baseline LDL-C level in Korea. It is expected that our findings will help clinical decision-making with regard to statin prescription, and this will help reduce national medical expenditure. [ABSTRACT FROM AUTHOR]

[Display omitted] • A framework for the simulation of spray flame synthesis is presented. • Validation of turbulent flame synthesis simulations with in situ measurements. • Investigation of temporal fluctuations in the particle size distribution. The synthesis of iron oxide nanoparticles from iron nitrate in the SpraySyn spray flame reactor was investigated by experiment and simulation. The focus was on the spray and flame structure, the particle growth by nucleation and coagulation, and the unresolved effects and their impact on the dispersed phase. The reacting flow was modeled in large eddy simulations with the premixed flamelet generated manifolds technique, including modifications for aerosol nucleation. Particle dynamics were described with a sectional model and a subgrid scale coagulation kernel. The particle size distributions at different distances from the burner surface were obtained using a particle mass spectrometer. The experiments and simulations are in good agreement for the flame centreline velocity and both size distribution and mean size of the particles (for particles larger 1 nm - the approximate detection limit of the experiment). Furthermore, simulations enabled to interpret the temporal evolution of the particle size distribution. [ABSTRACT FROM AUTHOR]

What is known and objective This study aimed to compare the ability of statin monotherapy (ST group), omega-3 fatty acid monotherapy (OM_A group) and combination therapy with omega-3 fatty acids and a statin (OM_S group), to reduce triglyceride (TG) levels in patients with hypertriglyceridaemia. Methods In this retrospective cohort study, we extracted data from the electronic medical records of patients initially prescribed either a statin or omega-3 fatty acids between January, 2009 and December, 2013. We performed a comparative analysis of the change in cholesterol levels between baseline and an average of 3 months later. Results and discussion Data were extracted for 2071 patients. The average daily eicosapentaenoic acid (EPA) ethyl ester and docosahexaenoic acid (DHA) ethyl ester intake was 1689 mg, and 79-86% of the OM_A and OM_S groups were prescribed two omega-3 fatty acid capsules. At a baseline TG level of between 200 and 500 mg/dL, TG levels were reduced by 16 ± 2·8% in the ST group, 28 ± 2·8% in the OM_A group and 29 ± 2·3% in the OM_S group ( P = 0·001 for ST group vs. OM_A and OM_S groups), with no difference between the OM_A and OM_S groups. At a baseline TG level ≥500 mg/dL, there was no difference in TG level reduction between the three groups (54 ± 7·3%, 55·8 ± 3·5% and 51·8 ± 6·8%, respectively, P = 0·851). What is new and conclusion Although omega-3 fatty acids are not considered the primary medication for hypertriglyceridaemia, the prescription of omega-3 fatty acids is justifiable if reduction in TG levels is judged to be necessary. [ABSTRACT FROM AUTHOR]