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The CPA equation of state is applied to model binary, ternary, and multicomponent mixtures that contain CO 2 with polyethylene glycols or compounds relevant to biodiesel production, such as glycerol and various triglycerides. Effort has been made to evaluate the model performance on correlating both the liquid and the vapor phase compositions, which is a demanding task, revealing the model's and parameters' limitations, due to the rather low concentrations of heavy compounds in the vapor phase. Initially the model's binary parameters, which in all cases were temperature independent, were estimated using experimental data for binary systems. Those parameters were used to predict the phase behavior of supercritical CO 2 containing ternary and multicomponent mixtures. Since no parameter was adjusted to ternary or multicomponent systems' data, the reported CPA results for such mixtures are considered as pure predictions. This is the final part of a series of studies [Tsivintzelis et al. Fluid Phase Equilibria 430 (2016) 75-92 and 504 (2020) 112337] that complete the parameterization of the CPA equation of state for systems relevant to the biodiesel production, which allows the application of the model to multicomponent mixtures of the relevant processes.

We present two different approaches for modeling the spread of the COVID-19 pandemic. Both approaches are based on the population classes susceptible, exposed, infectious, quarantined, and recovered and allow for an arbitrary number of subgroups with different infection rates and different levels of testing. The first model is derived from a set of ordinary differential equations that incorporates the rates at which population transitions take place among classes. The other is a particle model, which is a specific case of crowd simulation model, in which the disease is transmitted through particle collisions and infection rates are varied by adjusting the particle velocities. The parameters of these two models are tuned using information on COVID-19 from the literature and country-specific data, including the effect of restrictions as they were imposed and lifted. We demonstrate the applicability of both models using data from Cyprus, for which we find that both models yield very similar results, giving confidence in the predictions., Competing Interests: The authors have declared that no competing interests exist.

Objectives: To determine whether there were differences between different polyols (sugar alcohols) in terms of their ability to stimulate intolerance symptoms when consumed in milk chocolate. Also to discover whether symptomatology can be related to the dose of polyol ingested., Design: The study was of a randomised double-blind cross-over design., Subjects: 59 healthy volunteers aged 18-24 years were recruited from the student population of the University of Salford. All subjects successfully completed the trial., Interventions: Subjects ingested 100 g milk chocolate containing 40 g bulk sweetner as either sucrose, isomalt, lactitol or maltitol or a mixture (10:30 w/w) of sucrose and isomalt, sucrose and lactitol or sucrose and maltitol. Each bar was taken as breakfast on one day with following products consumed at 1-week intervals. Subjects reported the incidence and severity of the symptoms of flatulence, borborygms, colic, motion frequency and loose stools., Results: The ingestion of 30 g or 40 g lactitol resulted in a significant increase in the incidence and severity of all symptoms examined compared to reactions after the consumption of standard sucrose-containing chocolate (P <0.01). Similarly, 40 g isomalt led to an increased incidence of all symptoms, including mild laxation (P <0.01), but unlike lactitol none was rated as being severe. A reduction in isomalt to 30 g was marked by increased tolerance with evidence of only mild borborygms (P <0.01), mild flatulence, colic, and laxation (P <0.05), with no increase in motion frequency (P <0.35). Ingestion of 40 g maltitol caused less intolerance than 40 g isomalt, with evidence of only flatulence, borborygms and colic (P <0.01), symptoms being rated as only mild. A reduction to 30 g led to a decrease in all symptoms except mild flatulence. Maltitol did not have any laxative effect when ingested at either 30 g (P = 0.32) or 40 g (P = 0.13) per day., Conclusions: This work has shown that there are significant differences in the reporting of gastrointestinal symptomatology following the consumption of isomalt, lactitol and maltitol incorporated into milk chocolate. However, with all three polyols the incidence and severity of symptomatology was dose dependent.