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This article, published in the journal Thoracic & Cardiovascular Surgeon, examines the acute changes in biventricular intrinsic myocardial function that occur during percutaneous pulmonary valve implantation (PPVI) in patients with right ventricular outflow tract (RVOT) dysfunction. The study involved twenty patients who underwent PPVI, and their biventricular pressure-volume loops were assessed using a conductance catheter technique. The results showed that after PPVI, there was a significant decrease in right ventricular contractility and pulmonary arterial elastance, while left ventricular contractility remained unchanged. The study suggests that further investigation is needed to understand the long-term effects of these response patterns on biventricular remodeling. [Extracted from the article]

Accidental hypothermia (AH) presents a significant mortality risk, even in individuals with good health. Early recognition of the parameters associated with negative prognosis could save more lives.

In this study, we investigated the use of functionalized deep eutectic solvents (DESs) as a medium for CO2 capture integrated with CO2 desorption and biofixation in microalgal culture, as an approach for carbon capture, utilization, and storage (CCUS). The newly devised DES formulation—comprising choline chloride, ethylene glycol, and monoethanolamine—demonstrated a significant advancement in CO2 absorption capacity compared with conventional solvents. Effective CO2 desorption from the solvent was also achieved, recovering nearly 90% of the captured CO2. We then examined the application of the functionalized DESs to promote microalgal cultivation using a Chlorella sp. strain. The experimental results indicated that microalgae exposed to DES-desorbed CO2 exhibited heightened growth rates and enhanced biomass production, signifying the potential of DES-driven CO2 capture for sustainable microalgal biomass cultivation. This research contributes to the growing field of CCUS strategies, offering an avenue for efficient CO2 capture and conversion into valuable biomasses, thereby contributing to both environmental sustainability and bioresource use.

Non-aerated compost tea (CT) was prepared from compost derived from rockweed (Ascophyllum nodosum) and fish (cod, common ling, haddock, saithe) residues that fermented in water. Electrical conductivity, pH, concentrations of dry matter, ash, C, macronutrients (N, P, K, Ca, and Mg), and micronutrients (Cu, Fe, Mn, Mo, and Zn) of CT prepared under different fermentation conditions were measured. The effects of process factors, i.e., water/compost mass ratio (4.2–9.8 g/g) and fermentation time (4.2–9.8 days = 100–236 h), on the physicochemical properties of CT were quantified using quadratic polynomial models. CT obtained at optimal levels of process factors (4.2 g/g and 5.6 days = 134 h) was tested for lettuce seed germination and seedling growth. Diluted CT (25% CT + 75% ultrapure water) improved seedling growth while achieving a high germination percentage (97%).

Myocardial infarction is still a therapeutic rollercoaster challenge because, despite revolutionary treatments in its management, heart failure is still a consequence. Stem cell therapy might be a turning point in treating myocardial infarction patients for regaining what is lost—that is, myocardial tissue. This paper reviews the latest evidence for using stem cell therapy in the treatment of myocardial infarction, the results of this possible therapy regarding regaining cardiomyocytes, and the extent to which therapy with stem cells can be used in the future for the management of acute coronary syndromes.

Green catalysts used in the transesterification reaction of biodiesel must have biodegradability and non-toxicity as their main characteristics, being thus friendly to the environment, since they perform in processes in which the content of CO2, which is increasing from year to year, should be reduced. As a consequence, their manufacture can be extremely rigorous. This work presents the two-step construction, synthesis, and deposition of such a green heterogeneous catalyst and its testing in the catalysis of the transesterification of triglycerides with methanol, resulting in methyl esters. A CSTR-type reactor was used to perform transesterification, and the biodiesel yields obtained had values in the range of 91.7–95.7%, using 2, 3, and 4 g/g catalyst to oil, under conditions like those for obtaining commercial biodiesel in homogeneous catalysis, i.e., a 65 °C process temperature and a 4:1, 5:1 or 6:1 methanol-to-oil molar ratio.

Abstract The paper has aimed at studying the transfer of indole 3-acetic acid (IAA) from a feed aqueous solution to a stripping aqueous solution of NaOH using a chloroform bulk liquid membrane and trioctylamine (TOA) as a ligand (L). Initial molar concentrations of IAA in the feed phase, c IAA,F0 (10–4–10–3 kmol/m3), of TOA in the membrane phase, c L,M0 (10–2 and 10–1 kmol/m3), and of NaOH in the stripping phase, c NaOH,S0 (10–2 and 1 kmol/m3), were selected as process factors. Their effects on the final values of IAA concentration in the feed phase (c IAA,Ff ) and stripping solution (c IAA,Sf ), extraction efficiency (E F ), distribution coefficient (K D ), and recovery efficiency (E R ) were quantified using multiple regression equations. Regression coefficients were determined from experimental data, i.e., c IAA,Ff,ex = 0.02–1 × 10–4 kmol/m3, c IAA,Sf,ex = 0.22–2.58 × 10–3 kmol/m3, E F,ex = 90.0–97.9%, K D,ex = 9.0–46.6, and E R,ex = 66.5–94.2%. It was found that c IAA,F0 had the most significant positive effect on c IAA,Ff and c IAA,Sf , whereas c NaOH,S0 had a major positive effect on E F , K D , and E R . A deterministic model based on mass transfer of IAA was developed and its parameters, i.e., mass transfer coefficient of IAA-L complex in the liquid membrane (0.82–11.5 × 10–7 m/s) and extraction constant (1033.9–1779.7 m3/kmol), were regressed from experimental data. The effect of c L,M0 on both parameters was significant.

The present work focuses on the problem of steel surface corrosion as a kinetic expression when water droplets are repeatedly deposited and evaporated on/from its surface. This process, together with the rainwater film corrosion process, belongs to the theoretical foundations of the problem of atmospheric corrosion. It was considered that the formation of water droplets on surfaces is a random but repetitive process, as well as the fact that experimental and theoretical observations show that the droplet corrosion front of a metal surface is located in its zone circumference. We thus aimed to establish how the corrosion process evolves on a steel plate when many drops are deposited and removed repeatedly. An experimental setup and working procedure were used to obtain data characterizing the simultaneous process of steel surface corrosion and water droplet evaporation. For natural convection conditions with a variable relative humidity and temperature environment, an extensive data set consisting of the dynamics of individual droplet evaporation coupled simultaneously with the corrosion of the steel surface under the droplet was obtained. The mathematical models for evaporation and corrosion under the droplet have the same dynamic transfer surface for water evaporation and oxygen supply in the droplet. An approach for determining this surface depending on the momentary droplet mass was considered. Several simultaneous measurements of evaporation–corrosion dynamics were used to calibrate the coupled models, which were then used to show their compatibility with experimental data.

The paper focuses on the experimental investigation and mathematical modeling of the corrosion of steel when a film of water flows over its surface. The experimental monitoring of corrosion dynamics in the flowing film was carried out using a laboratory pilot model, exploited in such a way as to obtain data necessary to identify some characteristic parameters of the mathematical model of this problem. The mathematical model of the case takes into account the transfer of oxygen through the liquid film flowing on the surface of the corroding plate where the chemical surface processes characteristic of corrosion occur (dissolution of Fe, oxidation of Fe2+ to Fe3+, formation of surface deposit, etc.). Experimental measurements were used to identify the parameters of the mathematical model, especially the reaction constant of the Fe dissolution rate and the surface oxidation yield of Fe2+ to Fe3+. Calculation of the correlation coefficients for the apparent constant surface reaction rate and process factors showed that they correlate strongly and non-linearly with the Reynolds number (Re) of the film flow, with the cumulative flow duration, and with the cumulative standby time of the experiments. Using the dynamics of the resistance to the transfer of oxygen through the rust film and the dynamics of its thickness resulting from the specific flow of rust deposition, the apparent oxygen diffusion coefficient through the rust film formed on the plate was expressed.

Abstract Two Markov-type stochastic models were developed to describe the kinetics of acid hydrolysis of cellulose. One of them involved a Gauss (normal) distribution of probabilities of chemical bond breaking, the other a Weibull distribution. It was considered that the random breaking of cellulose was based on the cleavage of a parent macromolecule into two descendants. Model equations and kinetics of acid hydrolysis of cellulose consisting of 10 and 100 units of cellobiose were presented. The effects of acid concentration and temperature on the kinetics of hydrolysis process were taken into account. The results obtained applying both stochastic models were in a reasonable agreement with those obtained using a deterministic kinetic model. These stochastic models can accurately describe the kinetics of acid hydrolysis and cover the drawbacks of some deterministic kinetic models, e.g., large number of model equations and parameters, modification of parameter values by changing the process conditions.