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In particular, two VC performance measures; (1) linear displacement of the centroid of RGC activation, and (2) the RGC activation size consistency as a function of different current ratios α, have comparable performance under asynchronous and synchronous stimulation with appropriately selected stimulation parameters.

Our findings support the possibility of creating VCs in the retina under both synchronous and asynchronous stimulation conditions. The results provide theoretical evidence for future retinal prosthesis designs with higher spatial resolution and power efficiency whilst reducing the number of current sources required to achieve these outcomes.

Our findings support the possibility of creating VCs in the retina under both synchronous and asynchronous stimulation conditions. The results provide theoretical evidence for future retinal prosthesis designs with higher spatial resolution and power efficiency whilst reducing the number of current sources required to achieve these outcomes.In this work we investigate TiO2 and BiVO4 nanostructures by means of density functional theory (DFT) calculations, to provide an estimate of the band alignment in TiO2/BiVO4 interfaces, highly active in photo-electrochemistry and photocatalytic water splitting. Calculations were carried out with both DFT range separated and self-consistent dielectric dependent hybrid functionals (HSE06 and PBE0DD). The impact of systems' size has been investigated. The converged electronic levels of TiO2 and BiVO4 surfaces have been used to predict the band alignment in TiO2/BiVO4 heterostructures. Results indicated that when TiO2 (101) surface is matched with BiVO4 (110), a type-II alignment is obtained, where the band edges of BiVO4 are higher in energy that those of TiO2. This picture is favorable for charge-carriers separation upon photoexcitation, where electrons move toward TiO2 and holes toward BiVO4. On the contrary, if TiO2 (101) is interfaced to BiVO4 (010) the offset between the band edges is negligible, thus reducing the driving force toward separation of charge carriers. These results rationalize the dependence on the facet's exposure of the observed photocatalytic performances of TiO2/BiVO4 composites, where the TiO2 (101)/BiVO4 (110) interface outperforms the TiO2 (101)/BiVO4 (010) one.Proton beams are widely used worldwide to treat localized tumours, the lower entrance dose and no exit dose, thus sparing surrounding normal tissues, being the main advantage of this treatment modality compared to conventional photon techniques. Clinical proton beam therapy treatment planning is based on the use of a general relative biological effectiveness (RBE) of 1.1 along the whole beam penetration depth, without taking into account the documented increase in RBE at the end of the depth dose profile, in the Bragg peak and beyond. selleck products However, an inaccurate estimation of the RBE can cause both underdose or overdose, in particular it can cause the unfavourable situation of underdosing the tumour and overdosing the normal tissue just beyond the tumour, which limits the treatment success and increases the risk of complications. In view of a more precise dose delivery that takes into account the variation of RBE, experimental microdosimetry offers valuable tools for the quality assurance of LET or RBE-based treatsed to assess the RBE variation of a 62 MeV modulated proton beam along its penetration depth. The microdosimetric assessment of the RBE based on the Loncol's weighting function is in good agreement with radiobiological results when the 10% biological uncertainty is taken into account.3D bioprinting has seen a tremendous growth in recent years in a variety of fields such as tissue engineering, drug testing and regenerative medicine, which has led researchers and manufacturers to continuously advance and develop novel bioprinting techniques and materials. Although new bioprinting methods are emerging (e.g. contactless and volumetric bioprinting), micro-extrusion bioprinting remains the most widely used method. Micro-extrusion bioprinting, however, is still largely dependent on the conventional pneumatic extrusion process, which relies heavily on homogenous biomaterial inks and bioinks to maintain a constant material flow rate. Augmenting the functionality of the bioink with the addition of nanoparticles, cells or biopolymers can induce inhomogeneities resulting in uneven material flow during printing and/or clogging of the nozzle, leading to defects in the printed construct. In this work, we evaluated a novel extrusion technique based on a miniaturized progressive cavity pump which allows precise control over the volumetric flow rate by positive displacement. We compared the accuracy and precision of this system to the pneumatic extrusion system and tested both systems for their effect on cell viability after extrusion. The progressive cavity pump achieved a significantly higher accuracy and precision compared to the pneumatic system, while maintaining good viability. These improvements were independent of the bioink composition, printing speed or nozzle size. This study demonstrates the merit of precise extrusion-process control in bioprinting by progressive cavity pumps and investigates their influence on process-induced cell damage. Progressive cavity pumps are a promising tool for bioprinting and could help provide standardized and validated bioprinted constructs while leaving the researcher more freedom in the design of the bioinks.Three-dimensional (3D)-printed scaffolds have proved to be effective tools for delivering growth factors and cells in bone-tissue engineering. However, delivering spheroids that enhance cellular function remains challenging because the spheroids tend to suffer from low viability, which limits bone regenerationin vivo. Here, we describe a 3D-printed polycaprolactone micro-chamber that can deliver human adipose-derived stem cell spheroids. Anin vitroculture of cells from spheroids in the micro-chamber exhibited greater viability and proliferation compared with cells cultured without the chamber. We coated the surface of the chamber with 500 ng of platelet-derived growth factors (PDGF), and immobilized 50 ng of bone morphogenetic protein 2 (BMP-2) on fragmented fibers, which were incorporated within the spheroids as a new platform for a dual-growth-factor delivery system. The PDGF detached from the chamber within 8 h and the remains were retained on the surface of chamber while the BMP-2 was entrapped by the spheroid.