Glass and bioactive glass–ceramic can be used in several applications. In bone growth where good bone/biomaterial adhesion was required, bioactive coatings for implants can improve bone formation. The glass and glass–ceramics of the LZS (Li2O‐ZrO2‐SiO2) system are very interesting because of their mechanical, electrical, and thermal properties. Very recently, their biological response in contact with human osteoblast has been evaluated. However, despite several initiatives, there are still no studies that systematically assess this system's bioactivity, dissolution, and cytotoxicity in vitro. This work aims to investigate the dissolution, bioactivity behavior, and cytotoxicity of LZS glass–ceramic. LZS glass–ceramics were produced from SiO2, Li2CO3, and ZrSiO4 by melting followed by quenching. The obtained glass frits were milled and uniaxially pressed and heat‐treated at 800 and 900°C and submitted to physical–chemical, structural and mechanical characterization. Their dissolution behavior was studied in Tris–HCl, while bioactivity was performed in simulated solution body fluid (SBF). The cytotoxicity test was performed using glass–ceramic in direct contact with mesenchymal stem/stromal cells (SC) isolated from human exfoliated deciduous teeth. Structural and microstructural analyzes confirmed bioactivity. The results show that it was possible to produce bioactive glass–ceramic from LZS, proven by the formation of new calcium phosphate structures such as hydroxyapatite on the surface of the samples after exposure to SBF. The SC viability test performed indicated that the materials were not cytotoxic at 0.25, 0.5, and 1.0 mg/ml. The glass–ceramic system under study is very promising for a medicinal application that requires bioactivity and/or biocompatibility for bone regeneration.

Abstract. Fagundes M, Santos EML, Duarte KLR, Santos LM, Vieira JS, Oliveira CHD, Silva PS. 2020. Diversity of gall-inducing insect associated with a superhost plant species: Plant architecture, resource availability and interspecific interactions. Biodiversitas 21: 1182-1189. The role of interspecific competition in the organization of herbivorous insect communities may vary depending on resource availability. Trees are structurally more complex and have greater resource availability for herbivorous insects than shrubs. In this study, we evaluated the roles of plant architecture and interspecific interactions on community organization of the gall-inducing insect associated with trees (adult plants) and shrubs (young plants) of Copaifera langsdorffii. Our results showed that the species composition of gall-inducing insect communities associated with C. langsdorffii differed statistically between trees and shrubs. In addition, the trees presented greater diversity of gall-inducing insects than the shrubs, corroborating the hypothesis of plant architecture. The results of the analysis of null models showed that the co-occurrence of gall-inducing insect species associated with trees not differ from the co-occurrence predicted by chance. Thus, interspecific interactions cannot be used to explain the community organization of the gall-inducing insects on C. langsdorffii trees. On the other hand, the co-occurrence of gall-inducing insect species differed from the co-occurrence predicted by chance when shrubs plants were analyzed, indicating that biotic interactions can shape the structure of the gall-inducing insect community on shrubs. The lower availability of oviposition sites probably generates a dispute for these resources among females of different species of gall-inducing insects only in the shrubs. Therefore, the role of competition in the organization of herbivore insect communities on their host plant may vary depending on the ontogenetic stage of the host plant.

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Currently, magnetic nanoparticles are widely studied with regard to their application in cancer treatment. This study aims to show a straightforward strategy for the production of Fe3O4 nanoparticles (NPs) with biocompatible surface modifications with polycaprolactone (PCL) for biomedical purposes. The effects of the polymer coating on the properties of magnetite were evaluated. Crystallinity, morphology, composition, hydrodynamic size and magnetic properties of the produced nanoparticles were analysed via X-ray diffractometry (XRD), Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and Vibrating Sample Magnetometry (VSM), respectively. The proposed method produced nanoparticles of magnetite with an average size between 9 and 11 nm, with spherical morphology and superparamagnetic properties. Magnetization values were not compromised even when the highest amount of polymer was used in the surface modification. On the other hand, the coating resulted in the decrease of the hydrodynamic size of the composites, indicating greater colloidal stability when the polymer was present. The obtained nanoparticles showed maintenance of significant superparamagneticbehavior, even in the presence of PCL on their surface. This phenomenon would allow for their application as a further optimized vector in hyperthermia cancer treatment, controlled drug delivery and resonance imaging. Keywords: Nanoparticles; Magnetite;PCL; Cancer; Hyperthermia