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RAS is a signaling protein associated with the cell membrane that is mutated in up to 30% of human cancers. RAS signaling has been proposed to be regulated by dynamic heterogeneity of the cell membrane. Investigating such a mechanism requires near-atomistic detail at macroscopic temporal and spatial scales, which is not possible with conventional computational or experimental techniques. We demonstrate here a multiscale simulation infrastructure that uses machine learning to create a scale-bridging ensemble of over 100,000 simulations of active wild-type KRAS on a complex, asymmetric membrane. Initialized and validated with experimental data (including a new structure of active wild-type KRAS), these simulations represent a substantial advance in the ability to characterize RAS-membrane biology. We report distinctive patterns of local lipid composition that correlate with interfacially promiscuous RAS multimerization. These lipid fingerprints are coupled to RAS dynamics, predicted to influence effector binding, and therefore may be a mechanism for regulating cell signaling cascades.

Wastewater production is a major environmental issue for the leather and textile industries: in a modern plant, several synthetic dyes are used in separated coloring batches whose wastewaters are usually mixed, diluted with other process water streams, and sent to a unique wastewater treatment plant. This includes specific physical and biochemical tertiary treatments to remove dyes efficiently. One of the main difficulties of these processes is the presence of multiple dyes, which cannot be treated with the same efficiency as a "wide-spectrum" process. This work explores the possibility of using conventional granular activated carbon (GAC) and a new polyurethane foam (PUF) for the adsorption of an acid red dye in the wastewater of a specific coloring batch of the tanning industry. The aim of this work is twofold: on the one hand, we aim to explore the performance of the new PUF sorbent; on the other hand, we aim to explore the possibility of using adsorption as an optimized pre-treatment for single-dye batches, which may take advantage of the presence of a single type of target dye and its higher concentration. The effluent is then sent to the wastewater treatment plant for further depuration. [ABSTRACT FROM AUTHOR]

The development of improved methods for surface disinfection has gained renewed interest during the first waves of the SARS-COV2 Pandemic when the need to assure massive disinfection of objects and spaces goes against that of reducing the consumption of chemicals and minimize the impact of disinfectants on exposed persons. Electrohydrodynamic atomization is considered a valuable option to improve disinfection efficiency, thanks to the benefits associated with the droplets charge. This paper presents preliminary experimental and model results on the application of an induction charging electrohydrodynamic atomisation process to the spraying of water solution of a conventional disinfectant under model conditions. In particular, electrospraying under simple jet mode with a whipping breakup has been tested. Experiments are aimed to characterize the droplet size distribution, the energy requirements and the spray coverage area over a target surface, while a simplified physical mathematical model is used to estimate the amount of disinfectant lost upon evaporation and the distribution of the droplets over the target surface. The electrospray is able to disperse droplets having a charge-to-mass ratio of around 1.67 mC/kg with an energy consumption of 23.4±7.8 J/L, being more efficient than other conventional hydraulic nozzles. These preliminary findings indicate a good matching between modelled and experimental data and suggest that electrospraying under simple jet mode with a whipping breakup can be a possible option for the spraying of disinfectants over surfaces. [ABSTRACT FROM AUTHOR]

The rapid human evolution has improved the quality of our lives through the use of technology. This not only resulted in increased raw materials extraction but also in the production of a worrying amount of electronic wastes. Indeed, in 2019 worldwide production of Electronic and Electric Equipment Waste (WEEE) was worth 50 million tons, causing several disadvantages such as the reduced space in landfills and massive shipping to countries with less restrictive regulations. On the other side, the billionaire electrical devices market is causing a significant increase in Precious Metals (PM) demand. Nowadays, the economic importance of PMs is as high as their supply risk. The answer to this problem consists of finding selective methods to extract and raffinate precious metals from disposed WEEE. On average, WEEEs contain around 30 % of plastics, 30 % ceramics, and 40 % metals; among these only around 0.1 % is characterized by PMs, such as gold, silver, rhodium, platinum, and palladium. The separation of PMs from other non-precious components is generally obtained using pyrometallurgy, which consists of fusing the wastes at temperatures up to 1500 ÷ 1700 °C. However, this method produces toxic gaseous byproducts and implies high energy costs. A possible alternative is given by hydrometallurgical processes, consisting of leaching the WEEE with solutions containing acids and oxidants at temperatures lower than 100°C. One of the main issues of the hydrometallurgical process is to leach copper and other non-precious base-metals selectively while keeping PMs in the solid-state. In this work, we report preliminary results of equilibrium and kinetic leaching tests in a well-stirred batch reactor, aimed at the optimization of the main operating parameters of a hydrometallurgical process for selective leaching of copper and other base-metals from Wasted Printed Circuit Boards (WPCBs). In particular, experiments have been carried out at different HCl and NaCl concentrations of the leaching solutions, exploring also the effect of temperature variation (20, 50, and 70 °C). [ABSTRACT FROM AUTHOR]

Since the last fifteen years, Flue Gas Desulphurization (FGD) plants based on seawater scrubbing found an interesting application in the maritime transportation, as an answer to the stringent regulations imposed by International Maritime Organization (IMO) on sulphur emissions. This work reports the experimental results on desulphurization in a pilot seawater scrubber (DN 400) from a marine Diesel engine (80 kW) operated under different loads (10, 25 and 50%). The pilot scrubber was fed with a gas velocity 0.15 m/s and a liquid to gas mass ratio 1 - 3 kg/kg. The scrubbing liquid was available at different alkalinity and salinity levels representing the ion speciation of marine water in different geographic areas. The experiments evaluate the SO2 removal efficiency of the scrubber as a function of seawater alkalinity and pH. Finally, the paper reports a correlation to assess the seawater flow rate required to comply with the current IMO restrictions. This correlation allows tuning the seawater flow rate during the ship navigation based on the registered marine alkalinities and to the operating conditions of the engine. The model can be integrated in the scrubber control system to identify optimal operating conditions and reduce pumping costs, helping to reduce the EEDI and the SEEMP ships energy indexes. [ABSTRACT FROM AUTHOR]

Oxidative scrubbing using different oxidizing chemicals (e.g. sodium chlorite, NaClO2) has been proposed since several years for gas emissions control. Although higher performances than conventional after-treatment process currently in use can be reached, these technologies have not yet found a consolidated application in the power generation and other industrial fields, due to excessive chemical consumption and the formation of some harmful contaminants in the wash water that must be removed with specific treatment systems. This work reports an experimental investigation of an oxidative wet scrubber for NOx removal from a simulated flue-gas containing 1030 ppmv of nitrogen oxides, using a scrubbing liquid doped with sodium chlorite (NaClO2) as oxidizing chemical. The experiments are performed in a packed column operating in countercurrent flow with a constant gas velocity of 1.15 m/s at 60 °C and a liquid-to-gas ratio variable from 1.25 to 4.06 L/m³. The packed column with a DN 100 is equipped with 892 mm of Mellapak 250.X packing. The experimental removal efficiencies of NOx are evaluated in function of the liquid flow rate and NaClO2 loading. These data allow to determine the specific NaClO2 dosage required to achieve a fixed NOx removal. Finally, a predictive correlation for wet oxidative scrubbing is also developed. [ABSTRACT FROM AUTHOR]