Electronic structures of 24-valence-electron full Heusler compounds investigated by density functional and GW calculations.

The electronic structures of Fe-based and Ru-based full Heusler compounds have been investigated systematically by density functional theory (DFT) with PBE, PBE  +  U, and HSE06 exchange-correlation (XC) functionals. In order to have a better systematic and quantitative comparison between the results of different approximations, the average deviation of eigenvalues (ADE) between any two electronic band structures were calculated. From quantitative analysis of the ADEs, we have shown that different XC functionals used in the DFT calculations will result in very different and inconsistent electronic band structures.

Puzzle of magnetic moments of Ni clusters revisited using quantum Monte Carlo method.

The puzzle of the magnetic moments of small nickel clusters arises from the discrepancy between values predicted using density functional theory (DFT) and experimental measurements. Traditional DFT approaches underestimate the magnetic moments of nickel clusters. Two fundamental problems are associated with this puzzle, namely, calculating the exchange-correlation interaction accurately and determining the global minimum structures of the clusters.

The Effect of Contamination of Implant Screws on Reverse Torque.

Purpose: To determine if contamination of abutment screws with titanium nanoparticles affects the preload by measuring the reverse torque after multiple cycles of screw closing-opening.

Materials And Methods: The study included 30 internal hex implants, titanium abutments, and titanium abutment screws. Fifteen abutment screws were contaminated with 60- to 80-nm titanium nanoparticles (contamination group), and the remaining 15 screws did not receive titanium nanoparticle contamination (noncontamination group).

A retrospective study of complications associated with 100 consecutive maxillary sinus augmentations via the lateral window approach.

Purpose: To report the complications encountered during 100 consecutive maxillary sinus augmentations via the lateral window approach and to propose solutions to manage these complications.

Materials And Methods: Pretreatment residual bone heights and the presence of septa were recorded. The incidences of any intraoperative or postoperative sinus complications such as excessive bleeding, membrane perforation, infection, wound dehiscence, sinusitis, loss of bone graft, and implant success were reported.

Size effect of Pd clusters on hydrogen adsorption.

The size effect of Pd clusters on hydrogen adsorption was investigated by density functional theory calculations. From molecular dynamics simulations, we found that the hydrogen molecules were dissociatively adsorbed on the Pd clusters; the most stable adsorption site was the hollow site. We also found that the adsorption energy increased as the size of Pd clusters decreased.

Efficacy of platelet-rich plasma on wound healing in rabbits.

Background: The purpose of this study was to evaluate if the healing of full-thickness skin wounds was accelerated by platelet-rich plasma (PRP).

Methods: Four 2.5 x 2.