The von Kármán street behind a circular cylinder: flow control through synthetic jet placed at the rear stagnation point

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Influence of Machine Learning-based active flow control on the turbulent statistics of the flow over a circular cylinder

The aim of the present paper is to investigate the capabilities of Machine Learning (ML) to reduce the aerodynamic drag of a circular cylinder in cross flow, by actively controlling its wake with a synthetic jet

Artificial Protein Coronas Enable Controlled Interaction with Corneal Epithelial Cells: New Opportunities for Ocular Drug Delivery

Topical administration is the most convenient route for ocular drug delivery, but only a minor fraction is retained in the precorneal pocket. To overcome this limitation, numerous drug delivery systems (DDS) have been developed. The protein corona (PC) is the layer of biomolecules (e.g., proteins, sugars, lipids, etc.) that forms around DDS in physiological environments by non-covalent interaction. The PC changes the DDS physical–chemical properties, providing them with a completely novel biological identity. The specific involvement of PC in ocular drug delivery has not been addressed so far. To fulfill this gap, here we explored the interaction between a library of four cationic liposome-DNA complexes (lipoplexes) and mucin (MUC), one of the main components of the tear film. We demonstrate that MUC binds to the lipoplex surface shifting both their size and surface charge and reducing their absorption by primary corneal epithelial cells. To surpass such restrictions, we coated lipoplexes with two different artificial PCs made of Fibronectin (FBN) and Val-Gly-Asp (VGA) tripeptide that are recognized by receptors expressed on the ocular surface. Both these functionalizations remarkedly boosted internalization in corneal epithelial cells with respect to pristine (i.e., uncoated) lipoplexes. This opens the gateway for the exploitation of artificial protein corona in targeted ocular delivery, which will significantly influence the development of novel nanomaterials

Effect of rMnSOD on sodium reabsorption in renal proximal tubule in Ochratoxin A - treated rats

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium that represent toxic real threat for human beings and animal health. In this study we evaluated the effect of a new recombinant mitochondrial manganese containing superoxide dismutase (rMnSOD) on oxidative stress and on the alterations of fluid reabsorption in renal proximal tubule (PT) as possible causes of OTA nephrotoxicity. Finally, we have measured the concentration of O2 - in the kidney through dihydroethidium assay (DHE) and nitric oxide (NO) concentration through nitrites and nitrates assay. Male Sprague Dawley rats weighing 120-150 g were treated for 14 days by gavage, as follows: Control group, 12 rats received a corresponding amount of saline solution (including 10% DMSO); rMnSOD group, 12 rats treated with rMnSOD (10 μg/kg bw); OTA group, 12 rats treated with OTA (0,5 mg/Kg bw) dissolved in 10% DMSO and then scaled to required volume with corn oil; rMnSOD + OTA, 12 rats treated with rMnSOD (10 μg /kg bw) plus OTA (0,5 mg/Kg bw). Our results have shown that rMnSOD restores the alteration of reabsorption in PT in rats treated with OTA plus rMnSOD, probably through the response to pressure natriuresis, where nitric oxide plays a key role. Moreover, rMnSOD prevents the nephrotoxicity induced by OTA probably restoring the balance between superoxide and NO that is most probably the cause of hypertension and renal functional alterations through the inhibition of NO synthase. In conclusion these data provide important information for understanding of mechanism of toxic action of OTA

Machine Learning-based active control and PIV measurements of a circular cylinder wake

The aim of the present paper is to investigate the fluid dynamic evolution of a circular cylinder wake controlled by a synthetic jet (SJ) to reduce the related aerodynamic drag via Particle Image Velocimetry (PIV

Comment on Celentano et al. Suitability of a Progenitor Cell-Enriching Device for In Vitro Applications. Coatings 2021, 11, 146

The intent of this letter is to comment on an article entitled “Suitability of a Progenitor Cell-Enriching Device for In Vitro Applications” [...

The macroeconomic impact of organised crime: A post-Keynesian analysis

The paper proposes an extended post-Keynesian model, where effective demand drives income levels and growth rates, to explain how organised crime affects the economy. In our set-up, some criminal activities, such as extortion, the criminal trade and corruption, reduce demand by draining resources from the legal sector; whereas others, such as money laundering, increase demand. The model determines under which conditions each effect prevails. Finally, we perform a simulation exercise that considers Italy, showing that the size of the criminal trade is so excessively large that organised crime impacts negatively on the Italian economy. In this context, we also provide several policy recommendation

Flow field features of fractal impinging jets at short nozzle to plate distances

An experimental analysis of the flow field generated by an impinging jet equipped with a fractal grid insert located at the nozzle exit is carried out by means of Tomographic Particle Image Velocimetry. The Reynolds number based on the nozzle exit section diameter d is set to 15,000. The presence of the grid leads to a non uniform curvature of the jet shear layer. As a consequence, azimuthal instabilities are triggered in proximity of the nozzle exit section, causing the production of streamwise vortices. Furthermore, the organization of the coherent structures in proximity of the impinged wall is discussed and related to the convective heat transfer distribution. Owing to the presence of counter rotating wall vortices along the diagonals of the on-plate imprint of the fractal grid, a region of minimum in the scalar transfer map can be detected. In addition to that, similarly to the well known vortex rings that characterize the case of round jet without turbulence promoter, the presence of azimuthally coherent structures that might be generated by Kelvin–Helmholtz instability of the jet shear layer is presented and discussed