Previous studies have revealed the propensity of elastin-based biopolymers to form amyloid-like fibers when dissolved in water. These are of interest when considered as "ancestral units" of elastin in which they represent the simplest sequences in the hydrophobic regions of the general type XxxGlyGlyZzzGly (Xxx, Zzz = Val, Leu). We normally refer to these biopolymers based on elastin or related to elastin units as "elastin-like polypeptides". The requirement of water for the formation of amyloids seems quite interesting and deserves investigation, the water representing the natural transport medium in human cells. As a matter of fact, the "natural" supramolecular organization of elastin is in the form of beaded-string-like filaments and not in the form of amyloids whose "in vivo" deposition is associated with some important human diseases. Our work is directed, therefore, to understanding the mechanism by which such hydrophobic sequences form amyloids and any conditions by which they might regress to a non-amyloid filament. The elastin-like sequence here under investigation is the ValGlyGlyValGly pentapeptide that has been previously analyzed both in its monomer and polymer form. In particular, we have focused our investigation on the apparent stability of amyloids formed from poly(ValGlyGlyValGly), and we have observed these fibers evolving to a hydrogel after prolonged aging in water. We will show how atomic force microscopy can be combined with X-ray photoelectron spectroscopy to gain an insight into the spontaneous organization of an elastin-like polypeptide driven by interfacial interactions. The results are discussed also in light of fractal-like assembly and their implications from a biomedical point of view.

A summary of selected thermophysical properties of refractory metallic carbides is reported with a critical evaluation of the data. A target of this work was to collect a wide and selected set of data spanning from physical and physico‐chemical parameters to more specialistic physico‐mechanical items of informations, all useful for technological applications. A second target was to obtain a comprehensive view of the matter concerning cubic carbides. On the collected data the authors have carried out a number of elaborations, correlation analyses, search for trends and graphic presentations in order to assess the validity of numerical figures inside a more general context and to extract some physical and/or physico‐chemical meaning also through the aid of proposed equations.

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The supramolecular organisation of elastin and its soluble derivative alpha-elastin were studied by scanning and transmission electron microscopy. It was found a variety of different structures including filaments, fibrils, fibres, networks and dendritic, leaf-like forms. Self-similar patterns, extending for at least three orders of magnitude, were revealed, strongly suggesting the presence of fractal objects. The fractal dimension D was determined by using the box counting method.

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The ultrashort pulsed laser deposition of vanadium oxide thin films has been carried out by a frequency-doubled Nd:glass laser with a pulse duration of 250 fs. The characteristics of the plasma produced by the laser−target interaction have been studied by ICCD imaging and optical emission spectroscopy. The results confirm that an emitting plasma produced by ultrashort laser pulses is formed by both a primary and a secondary component. The secondary component consists of particles with a nanometric size, and their composition and spatial angular distribution influence the deposited films. In fact, these films, analyzed by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, and atomic force microscopy, are formed by the aggregation of a large number of nanoparticles whose composition is explained by a model based on equilibrium thermal evaporation from particles directly ejected from the target. On these basis, the presence in the films of a mixture of V2O5 and VO2 is discussed.