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The present study analyzed features of titanium surface modification using laser treatments (denoted as L50-Ti), evaluated its effects on the responses of MG-63 cells, and compared them to polished surfaces (P-Ti) and sandblasted and acid-etched surfaces (SLA-Ti). The P-Ti, SLA-Ti, and L50-Ti surfaces were examined by scanning electron microscopy and X-ray photoelectron spectroscopy. MG63 osteoblast-like cells were seeded on these surfaces, and cell adhesion, proliferation, and morphology were examined. Cell differentiation markers and local factors were also evaluated. The P-Ti surface presented parallel grooves with a smoother surface roughness. The SLA-Ti surface exhibited irregular peaks and valleys with hydrophobic properties, whereas the L50-Ti surface presented micro-/nanoporous structures with hydrophilic properties. Cell adhesion, proliferation, differentiation, and the production of prostaglandin E2 were greater on L50-Ti surfaces than those on P-Ti and SLA-Ti surfaces. Laser treatment can fabricate micro-/nanoporous Ti surfaces with hydrophilic properties, and these surface characteristics enhanced the responses of MG-63 cells.

Purpose To examine early bone tissue healing in dental implants incorporating StemBios cell therapy. Materials and methods SLAffinity samples were examined by scanning electron microscopy and atomic force microscopy. The clinical trial comprised 11 patients, who each received a dental implant in the mandible. Only one of these 11 patients received StemBios cell therapy in combination with the dental implant. The patients continued to be observed over a 4-month period after implantation using computed tomography and resonance frequency analysis. Results It was found that StemBios cell therapy promoted bone tissue healing in the case of the treated dental implant. The data indicated that stress altered more smoothly and declined faster in the patient who received the StemBios cell therapy than those without StemBios cell therapy over 4 months. Conclusion A dental implant with SLAffinity surface treatment, in combination with StemBios cell therapy, significantly promoted bone tissue healing, especially at early osseointegration compared with that of implants without StemBios cell therapy when monitored over a 4-month period.

The superlattice structures and coalescence of self-assembled FePt nanoparticles were studied by X-ray diffraction and absorption spectroscopy techniques. The as-synthesized superlattice structure was found to be an FCC-like one with 21±0.5 well-packed layers. During the annealing, the iron absorption K edge was found shifted to a higher energy as the annealing temperature increase. The shift of this iron K edge might be attributed to the quantum size effect, surface effect or oxidation effect.

A magnetic tunneling transistor (MTT) has been successfully fabricated by growing a magnetic tunneling junction on a pre-fabricated p–n junction. A magnetobase current change of roughly 6300% at room temperature with the common collector configuration has been observed. The variation of the base current caused by external magnetic field is from 1.9 to 123 nA. The working principle of this silicon-base MTT can be described by a circuit theory.

The structure and local environment of ZnO:CoFe were investigated. An epitaxial structure of ZnO thin film doped with CoFe on Al 2 O 3 substrate was confirmed by XRD. By fitting the Zn EXAFS spectra, the bond distances and coordination numbers of Zn atoms in the ZnO:CoFe show that Co and Fe ions replace some positions of zinc atoms. The XANES study of Zn and O also show that CoFe cluster formation in this system can be excluded.

(FePt)/sub 1-x/Cu/sub x/ nanoparticles were prepared by the simultaneous polyol reduction of platinum acetylacetonate and copper acetylacetonate, and the thermal decomposition of Fe carbonyl. The addition of copper reduces the transition temperature of disordered fcc structure to ordered L1/sub 0/ by about 50/spl deg/C-100/spl deg/C. Together with the X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) results, the structure of FePtCu ternary alloy was verified and the Fe site was replaced by Cu.

For studying the influence of the current passed through a metal line for the magnetic cells on semiconductors, we prepared two types of the devices. Case 1 is that only one patterned permalloy cell on top of the insulated metal strip, and two cells are beside the strip. Case 2 is that all three patterned magnetic cells are on top of the strip. The magnetic field needed to reverse the magnetization of a submicrometer-size permalloy single domain cell with aspect ratio of 6 is larger than that of a unpatterned millimeter-size permalloy thin film due to the dimension effect. Magnetic force microscopy images of the patterned cells before and after applying various electrical currents were investigated. We have observed that: 1) the magnetic field produced by the word line will not change the magnetic configuration of the magnetic cells near the wires; 2) the magnetic field produced by the word line is quite uniform; and 3) for small aspect ratio of the submicrometer magnetic cells (

X-ray absorption spectroscopy measurements have been made on 7-, 12-, and $23\text{\ensuremath{-}}\mathrm{nm}$ palladium particles, along with bulk material as reference. With decreasing particle size, the extended x-ray absorption fine spectra reveal a substantial contraction of the nearest-neighbor distance and a reduction of the average coordination number, but an increasing Debye-Waller factor. Meanwhile, the x-ray absorption near edge spectra show a decreasing density of unoccupied states with decreasing particle size.

The model of 1/f noise for a spin transistor have been studied. The sources of the 1/f noise have been differentiated into two. One source is from the PN junction with the major contributor of recombination, and the other from the giant magnetoresistance multilayer. Actual data was measured on a spin transistor while doing a simulation of the 1/f noise. The measured data matches the output of the simulations.