Our study includes a crystal with the natural abundances of B-10 and B-11 and a crystal highly enriched with B-10. The as-grown crystals contain isolated oxygen vacancies, lithium vacancies, and copper impurities, all in nonparamagnetic charge states. During an irradiation at 77 K with 60 kV x-rays,

doubly ionized oxygen vacancies trap electrons while singly ionized lithium vacancies and monovalent copper impurities trap holes. The vacancies return to their preirradiation charge states when the temperature of the sample is increased to approximately 90 K. Hyperfine interactions with B-10 and B-11 nuclei, observed between 13 and 40 K in the radiation-induced EPR and ENDOR ACP-196 datasheet spectra, provide models for the two vacancy-related defects. The electron trapped by an oxygen vacancy is localized primarily on only one of the two neighboring boron PF-6463922 manufacturer ions while the hole stabilized by a lithium vacancy is localized on a neighboring oxygen ion with nearly equal interactions with the two boron ions adjacent to the oxygen ion. (C) 2010 American Institute

of Physics. [doi: 10.1063/1.3392802]“
“Objectives. The clinical use of platelet-rich plasma (PRP) for preprosthetic surgery has been a matter of controversy until now. Only recently, a new blood preparation has been developed which results in platelet-rich fibrin (PRF). The objective of the present investigation was to examine the growth factor release from PRP and PRF in vitro.

Study design.

Whole blood samples from healthy participants (n = 10) were drawn to generate PRP and PRF. Human osteoblasts (O), human fibroblasts (F), and human osteoblast-derived osteosarcoma cells (Saos-2) were used for the cell selleck products culture. Cells of each cell line were cultivated, and PRP- or PRF-preparations added for ten days. The drawn medium was pooled and the quantities of growth factors (platelet-derived growth factor isomers AB and BB, insulin-like growth factor I, and transforming growth factor (TGF) isomers beta 1 and beta 2) analyzed by enzyme-linked immunosorbent assay.

Results. In osteoblast and Saos-2 cultures, cytokine concentrations were significantly higher for PRP than for PRF (P < .05). In fibroblast cultures, results were the same with the exception of TGF-beta 2 (P < .05).

Conclusions. This study demonstrates that PRP application in cell cultures leads to higher levels of growth factors than PRF application. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: 48-55)”
“The vulcanization properties, mechanical properties of hydrogenated nitrite rubber (HNBR) filled with carbon black (N550), zinc dimethacrylate (ZDMA), SiO2 independently and two of three kinds of fillers together were investigated, respectively. The filler-dispersion was characterized by the transmission electron microscopy (TEM) and dynamic mechanical properties.