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TiN granular thin films were deposited on SiO2 substrates using cathodic cage plasma nitriding (CCPN) and SEM images, roughness analysis, contact angle measurements, and X-ray diffraction (XRD) were employed to characterize the structure of these films varying time and temperature of the process. Results have shown an inverse relationship between roughness and contact angle. Thin films with low roughness have presented higher contact angle values, and the opposite was observed in the films with more prominent or more grains per area. TiN is a hydrophobic material, and the decrease of contact angle value presented in some films produced occur due to modification of the morphological characteristics, which the roughness measurements and hysteresis of contact angle confirmed it, specifically, for samples synthesized at 2h and 350°C, the roughness is the smallest, and the contact angle is the largest [(111.23±8.87)°]. This connection between roughness and contact angle is essential, and it can be used to describe and characterize the most types of thin films produced by plasma deposition and to infer the surface modifications with different atmospheres of treatment.

Herein, we propose the design of a nanoscaffold based on the hot-press transfer of vertically aligned multi-walled carbon nanotubes (VAMWCNT) onto matrices of electrospun poly (lactic acid) (PLA) fibers. To this end, we created a three-dimensional, bioactive and electrically conductive scaffold that combines the potential of PLA as a biomaterial with the physical-chemical and biological properties of VAMWCNT (PLA/VAMWCNT). Given the well-known hydrophobicity of carbon nanotubes, oxygen-plasma functionalization was applied to the scaffolds in order to attach oxygen-containing groups to their surfaces, with the plasma treatment also responsible for the exfoliation of the VAMWCNT's tips. After plasma-functionalization, electrochemical measurements showed that our scaffold presented an increased electroactive area (1.5-fold) with a ko value of 6.87×10−3cms−1, confirming its applicability as an electrode. Furthermore, we have also demonstrated the feasibility of electrodepositing nanohydroxyapatite (nHAp) crystals onto this nanoarchitectured material, improving its biomimetic and bioactive features. Preliminary biological assays revealed the viability of primary human osteoblast cells cultivated onto the PLA/VAMWCNT-nHAp scaffolds. This investigation has shed light on a practical approach to produce 3D–scaffolds by transferring VAMWCNT onto electrospun polymeric matrices. These novel materials may represent promising alternatives for future tissue engineering applications and thus should be studied further. Keywords: Electrospinning, Poly (lactic acid), Vertically-aligned multiwalled carbon nanotubes, Nanohydroxyapatite, Bone tissue regeneration

The use of nanostructured polymer composites has surged to the forefront as a promising class of hybrid materials to design biomimetic structures for biomedical applications. The association of two or more classes of nanomaterials not only improves the intrinsic properties of composites, but also presents structural and chemical similarity to organic and inorganic parts of our body. A plethora of chemistries, compositions, and nanofillers have been extensively used for biomedical applications, especially for tissue engineering purposes. The great challenge of nanostructured polymer composites is to mimic (chemically and structurally) the extracellular matrices from different parts of the human body to promote tissue regeneration. Herein, we discuss recent efforts and key research challenges regarding natural, synthetic, and hybrid polymers both with and without organic and inorganic fillers employed for biomedical applications. An overview of three-dimensional bioprinting using nanocomposite hydrogels is also presented. We hope that the final comments and future directions presented here will pave the way for designing and conducting innovative research within the field and by that extend the thematic and fundamental understanding.

The results of stratigraphic and tephrostratigraphic analyses of several pyroclastic levels, collected along the coastal sector of the Cilento region (southern Italy), are presented. Some of these levels are here described for the fist time, others, already known in literature, were reconsidered in order to better understand their stratigraphic position and to point out the possible volcanic sources. The main outcrops are located along the southern coast of the Campania region (Cilento coast). All pyroclastic layers are interbedded within coastal or continental successions younger than the substage 5e of the Last Interglacial (b130 ka) or cover erosional coastal morphologies belonging to the same period. Only in one site the sampled tephra can be considered older. As a consequence, the age range for their emplacement is constrained to the last 200 ka. The results of SEM-EDS analyses on well preserved glass fragments indicate a composition falling between the trachyte and phonolite fields of the TAS plot, as typical of Phlaegrean Fields products. By comparing their composition with those of the main tephra marker layers recorded in southern Italy, the correlation of the Cilento pyroclastic layers with well known eruptive episodes was hypothesised. In summary, four different eruptions were recognised. The first one is testified by a pyroclastic layer, not correlated with a terrestrial counterpart, covered by a Middle Pleistocene alluvial fan, the second one is the eruptive event emplacing the X-6 marker tephra layer, and dates around 107 ka, the third is the Campanian Ignimbrite eruption (39 ka), and the last one is testified by the layers correlated with the Y-3 tephra (about 30 ka). These pyroclastic layers can be useful tools for stratigraphic correlations of Late Quaternary successions in southern Italy.