A comprehensive study on copper incorporated bio-glass matrix for its potential antimicrobial applications

In this study, sol-gel derived Cu substituted 70S bioglass (70SiO2-(20-x) CaO–10P2O5-xCuO; where x = 0, 0.5, 1, 1.5) were synthesized as a new multifunctional bioactive glasses (BGs). The effect of Cu substitution in the bio-glass matrix was evaluated for its impact on pathogen (Escherichia coli and Staphylococcus aurous). Fourier Transform Infrared spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), X-Ray Diffraction (XRD), Inductively Coupled Plasma spectroscopy (ICP) and Scanning Electron Microscopy (SEM) revealed that the obtained powders are amorphous silicate glass. The substituted element is present in the desired molar concentration. In vitro bioactivity test was performed in SBF solution by immersion of bioglass pellets. Antibacterial test was carried out against Escherichia coli and Staphylococcus aureus. The results showed that the prepared BGs have a high acellular bioactivity observed by a fast formation of thick and continuous layer of carbonated hydroxyapatite (CHA). The antibacterial properties of the substituted bio-glass matrix was indicated by the growth inhibition of bacterial colonies. The obtained results showed that copper substituted bio-glass is having potential to avoid post-surgical infections and it also represents the capability of hard tissue regeneration.     

Access and Sharing Contents Through the Social Network: A POMDP Approach

Users interact in the social network by exchanging useful information. The huge amount of traffic generated requires the design of an accurate model for good management. Hence, knowing the consumers' access patterns is of a great interest for content owners. We propose a study of the access and sharing patterns based on the content's popularity. We suppose that popularity is inferred by the observation of the number of views. Our goal is twofold. On the one hand, we aim to help users select the optimal action that allows content owners to decide to change or not the used social network to another to increase their profits and, on the other hand, to assist consumers, according to their area of interest, to decide to access or not a posted content. We establish a threshold structure of the optimal policies based on a trade‐off study between profits (money, access to useful information, etc.) and costs (time spent to edit or consult content, etc.). The experimental results of the proposed analytical model show that both owners and consumers maximize their utility by choosing the best strategies.