Physical properties of zinc oxide films deposited by dual-ion-beam sputtering are analyzed to point out the performance of this technique for the deposition of this material. The films are deposited by sputtering a zinc oxide target with an argon-ion beam, while a second low-energy beam, the assistance ion beam, impinges directly on the growing films. Results are presented for ZnO films deposited at room temperature with different oxygen/argon ratios in assistance ion beam and different sputtering ion-beam currents. Elemental, structural, and electrical analyses have been performed on films. All the films show the typical crystallographic orientation, with the c axis perpendicular to the substrate. The oxygen percentage in the assistance ion beam plays an important role in controlling the electrical resistivity of the films.

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Extracellular vesicles (EVs) are involved in intercellular communication during carcinogenesis, and cancer cells are able to secrete EVs, in particular exosomes containing molecules, that can be transferred to recipient cells to induce pathological processes and significant modifications, as metastasis, increase of proliferation, and carcinogenesis evolution. FZD proteins, a family of receptors comprised in the Wnt signaling pathway, play an important role in carcinogenesis of the gastroenteric tract. Here, a still unknown role of Frizzled 10 (FZD10) protein was identified. In particular, the presence of FZD10 and FZD10-mRNA in exosomes extracted from culture medium of the untreated colorectal, gastric, hepatic, and cholangio cancer cell lines, was detected. A substantial reduction in the FZD10 and FZD10-mRNA level was achieved in FZD10-mRNA silenced cells and in their corresponding exosomes. Concomitantly, a significant decrease in viability of the silenced cells compared to their respective controls was observed. Notably, the incubation of silenced cells with the exosomes extracted from culture medium of the same untreated cells promoted the restoration of the cell viability and, also, of the FZD10 and FZD10-mRNA level, thus indicating that the FZD10 and FZD10-mRNA delivering exosomes may be potential messengers of cancer reactivation and play an active role in long-distance metastatization.

The fractal dimensions of soil and peat humic acids equilibrated for various lengths of time in aqueous suspension at different pH values were determined by measuring their turbidity as a function of wavelength, with collaboration by scanning electron microscopy (SEM). Particle‐size distributions of the humic acid systems were also determined. The analysis of the power‐law dependence of the turbidity on the wavelength revealed that soil and peat humic acids may exhibit either a nonfractal or a mass fractal nature. Peat humic acid could also be described as a surface fractal. The passage from one regime to another depended on the pH and equilibration time. With an increase of either factor, the mass fractal dimension of humic acids decreased from about 2.8 to values close to 1.0. This trend, supported by SEM observations, suggested that humic particles in suspension evolve from compact, almost space‐filled structures with smooth surfaces, to less compact, fragmented and elongated structures with increasingly rough and irregular surfaces as the pH or time increases. Values of the mass fractal dimension close to 2.5 would reflect diffusion‐limited aggregation (DLA), whereas values close to 2.1 would suggest a reaction‐limited cluster‐cluster (RLA) aggregation model for humic acid. The fractal dimension thus represents a numerical parameter able to describe quantitatively the morphological features assumed by humic particles in suspension and to provide information on the underlying aggregation processes.