Nanocomposites of high-density polyethylene with amorphous calcium phosphate: in vitro biomineralization and cytocompatibility of human mesenchymal stem cells.

Polyethylene is widely used as a component of implants in medicine. Composites made of high-density polyethylene (HDPE) containing different amounts of amorphous calcium phosphate nanoparticles were investigated concerning their in vitro biomedical performance. The nanoparticles were produced by flame spray synthesis and extruded with HDPE, the latter complying with Food and Drug Administration regulations.

Primary assessment of a self-adhesive gutta-percha material.

Aim: To evaluate a prototype gutta-percha material (Bio-Gutta), which is claimed to work without sealer because of its incorporated ultrafine bioactive glass particles, in terms of its induction of pH and calcium phosphate (CaP) precipitates, and its self-adhesiveness in root canals.

Methodology: Bio-Gutta was compared with conventional gutta-percha (GP, composition: 70 wt% ZnO, 30 wt% polyisoprene). Test and control materials (N = 3) were immersed in phosphate-buffered saline (PBS) at 37 °C for 30 days.

Thermoresponsive polymer induced sweating surfaces as an efficient way to passively cool buildings.

Buildings can be effectively cooled by a bioinspired sweating-like action based on thermoresponsive hydrogels (PNIPAM), which press out their stored water when exceeding the lower critical solution temperature. The surface temperature is reduced by 15 °C compared to that of a conventional hydrogel (pHEMA) and by 25 °C compared to the bare ground.

Electrical resistivity of assembled transparent inorganic oxide nanoparticle thin layers: influence of silica, insulating impurities, and surfactant layer thickness.

The electrical properties of transparent, conductive layers prepared from nanoparticle dispersions of doped oxides are highly sensitive to impurities. Production of cost-effective thin conducting films for consumer electronics often employs wet processing such as spin and/or dip coating of surfactant-stabilized nanoparticle dispersions. This inherently results in entrainment of organic and inorganic impurities into the conducting layer leading to largely varying electrical conductivity.

Magnetic switching of optical reflectivity in nanomagnet/micromirror suspensions: colloid displays as a potential alternative to liquid crystal displays.

Two-particle colloids containing nanomagnets and microscale mirrors can be prepared from iron oxide nanoparticles, microscale metal flakes and high-density liquids stabilizing the mirror suspension against sedimentation by matching the constituent's density. The free Brownian rotation of the micromirrors can be magnetically controlled through an anisotropic change in impulse transport arising from impacts of the magnetic nanoparticles onto the anisotropic flakes. The resulting rapid mirror orientation allows large changes in light transmission and switchable optical reflectivity.