APPLICATION TO AN ITALIAN DISTRIBUTION SYSTEM OF A MULTIOBJECTIVE OPTIMAL VOLT/VAR CONTROL STRATEGY: IMPROVEMENTS AND MANAGEMENT PROBLEMS

ABSTRAC

A hierarchical model for novel schemes of electrodialysis desalination

A new hierarchical model for the electrodialysis (ED) process is presented. The model has been implemented into gPROMs Modelbuilder (PSE), allowing the development of a distributed-parameters simulation tool that combines the effectiveness of a semi-empirical modelling approach to the flexibility of a layered arrangement of modelling scales. Thanks to its structure, the tool makes possible the simulation of many different and complex layouts, requiring only membrane properties as input parameters (e.g. membrane resistance or salt and water permeability). The model has been validated against original experimental data obtained from a lab scale ED test rig. Simulation results concerning a 4-stage treatment of seawater and dynamic batch operations of brackish water desalination are presented, showing how the model can be effectively used for predictive purposes and for providing useful insights on design and optimisation

Glycine-Spacers Influence Functional Motifs Exposure and Self-Assembling Propensity of Functionalized Substrates Tailored for Neural Stem Cell Cultures

The understanding of phenomena involved in the self-assembling of bio-inspired biomaterials acting as three-dimensional scaffolds for regenerative medicine applications is a necessary step to develop effective therapies in neural tissue engineering. We investigated the self-assembled nanostructures of functionalized peptides featuring four, two or no glycine-spacers between the self-assembly sequence RADA16-I and the functional biological motif PFSSTKT. The effectiveness of their biological functionalization was assessed via in vitro experiments with neural stem cells (NSCs) and their molecular assembly was elucidated via atomic force microscopy, Raman and Fourier Transform Infrared spectroscopy. We demonstrated that glycine-spacers play a crucial role in the scaffold stability and in the exposure of the functional motifs. In particular, a glycine-spacer of four residues leads to a more stable nanostructure and to an improved exposure of the functional motif. Accordingly, the longer spacer of glycines, the more effective is the functional motif in both eliciting NSCs adhesion, improving their viability and increasing their differentiation. Therefore, optimized designing strategies of functionalized biomaterials may open, in the near future, new therapies in tissue engineering and regenerative medicine

RNA-Based Assay for Next-Generation Sequencing of Clinically Relevant Gene Fusions in Non-Small Cell Lung Cancer

Gene fusions represent novel predictive biomarkers for advanced non-small cell lung cancer (NSCLC). In this study, we validated a narrow NGS gene panel able to cover therapeutically-relevant gene fusions and splicing events in advanced-stage NSCLC patients. To this aim, we first assessed minimal complementary DNA (cDNA) input and the limit of detection (LoD) in different cell lines. Then, to evaluate the feasibility of applying our panel to routine clinical samples, we retrospectively selected archived lung adenocarcinoma histological and cytological (cell blocks) samples. Overall, our SiRe RNA fusion panel was able to detect all fusions and a splicing event harbored in a RNA pool diluted up to 2 ng/µL. It also successfully analyzed 46 (95.8%) out of 48 samples. Among these, 43 (93.5%) out of 46 samples reproduced the same results as those obtained with conventional techniques. Intriguingly, the three discordant results were confirmed by a CE-IVD automated real-time polymerase chain reaction (RT-PCR) analysis (Easy PGX platform, Diatech Pharmacogenetics, Jesi, Italy). Based on these findings, we conclude that our new SiRe RNA fusion panel is a valid and robust tool for the detection of clinically relevant gene fusions and splicing events in advanced NSCLC

Modelling of Electrodialysis units by a multi-scale process simulator

Drinking water production by desalination is an interesting alternative to face water scarcity issues. Electrodialysis (ED) is an electro-membrane process that is actually gaining attention as a competitive alternative for seawater and brackish water desalination due to recent developments in manufacturing of high performance ion exchange membranes (IEMs). In this context, a suitable process simulator can be a very effective tool in order to drive the design of optimized ED systems. In this work a novel mathematical model of ED units was developed by a hierarchical simulation strategy of separation of scales, in order to address the full simulation problem. The model was implemented in PSE gPROMS Modelbuilder. In the lower-hierarchy model, transport phenomena of salt and water were simulated within the whole cell pair of an electrodialyser. Then, the higher-hierarchy model describes the behaviour of the stack. The model is based on mass balance equations and phenomenological expressions of fluxes that describe transport phenomena along channels and across IEMs. In addition, Kirchhoff’s law together with the Nernst’s law for the non-Ohmic voltage drop was used to determine the electrical behaviour of the equivalent circuit. Finally, the model makes use of CFD correlations from a lower scale as input data in order to predict the effect of concentration polarization and the contribution of pumping to the energy consumption. Co-current, counter-current and crossflow configurations were simulated, by obtaining the distribution of current density/voltage and concentration along the channels. Finally, total resistance, total power consumption and specific energy consumption were computed. Several simulations were carried out by changing the operating conditions and the stack features. Simulation results showed a good agreement with experimental findings as obtained from the literature, demonstrating that the model is able to adequately capture the phenomenological description of the ED process

Behavior in compression of concrete cylinders externally wrapped with basalt fibers

This paper gives additional information on the use of new class of composites constituted by Basalt Fiber Reinforced Polymer (BFRP) bonded with epoxy resin to concrete specimens as an alternative confinement material for compressed concrete members with respect to carbon or glass fibers. From the experimental point of view, concrete cylinders are wrapped with continuous fibers, in the form of sheets, applying both full and partial discrete wrapping with BFRP straps, and then tested in compression. For comparison, few other concrete cylinders are wrapped with Carbon Fiber Reinforced Polymer (CFRP) sheets and tested in compression. The number and type of plies (full or partial wrapping), the type of loading (monotonic and cyclic actions) and the type of fiber (basalt and carbon) are the main variables investigated. The experimental results obtained from the compressive tests in terms of both stress–strain curves and failure modes show the possibility of reducing the brittleness of unconfined concrete, resulting significantly increased both the post-peak resistance and the axial strain of confined concrete corresponding to BFRP failure. Form the analytical standpoint, a review of the available models given in the literature is made and verified against the experimental data. Finally, a proposal for analytical expressions aimed at the calculation of the compressive strength and corresponding strain of confined concrete is provided also including the strain at BFRP failure

Electrodialysis for water desalination: A critical assessment of recent developments on process fundamentals, models and applications

The need for unconventional sources of fresh water is pushing a fast development of desalination technologies, which proved to be able to face and solve the problem of water scarcity in many dry areas of the planet. Membrane desalination technologies are nowadays leading the market and, among these, electrodialysis (ED) plays an important role, especially for brackish water desalination, thanks to its robustness, extreme flexibility and broad range of applications. In fact, many ED-related processes have been presented, based on the use of Ion Exchange Membranes (IEMs), which are significantly boosting the development of ED-related technologies. This paper presents the fundamentals of the ED process and its main developments. An important outlook is given to operational aspects, hydrodynamics and mass transport phenomena, with an extensive review of literature studies focusing on theoretical or experimental characterization of the complex phenomena occurring in elec- tromembrane processes and of proposed strategies for process performance enhancement. An overview of process modelling tools is provided, pointing out capabilities and limitations of the different approaches and their possible application to optimisation analysis and perspective developments of ED technology. Finally, the most recent applications of ED-related processes are presented, highlighting limitations and potentialities in the water and energy industry

Electrodialysis with capacitive electrodes (CED): hierarchical process modelling for water desalination

The present work describes the development of the first dynamic model for CE

Modelling and characterization of electrodialysis systems for multi-ionic solutions

In this work a simplified approach related to membrane properties is require