No abstract

Generally, the parameter p • d (pressure × gap distance) in dielectric barrier discharge (DBD) controls the electrical breakdown and also the plasma characteristics. We investigated the optimum plasma transition p • d by controlling the pressure. To find the transition p • d (p • d tr ) condition, optical emission spectroscopy (OES) was used to measure emission spectra from the DBD. All p • d data were normalized by the second positive system of nitrogen molecules, the wavelength of which was 337.1 nm. Then we compared the relative intensities of species generated during the discharge by OES analysis. Species selected for comparison were the first negative system (FNS) of nitrogen molecules (391.4 nm) and atomic oxygen spectra (777.1 nm). Experimental results showed that relative intensities were almost constant as p • d decreased, but at specific p • d data, the intensity started to increase. The increase in FNS of nitrogen molecules means not only an increase in electron energy but also a change in the plasma mode, streamer to glow transition. In the case of DBD using alumina with 1 mm thickness applied ac power, the plasma transition occurred at the 1 Torr cm condition.

Recent concern about spinal problems in pregnancy is still pregnancy-related LBP. The further studies about its prevalence, risk factors, and treatment will be expected to continue. In both general spinal diseases and pregnancy-induced spinal diseases, there is no significant difference in treatment between pregnant women and ordinary people. Therefore, if consideration of possible spinal problems, exact diagnosis and adequate treatment are performed, good prognosis may be enough achieved in pregnant women.

PURPOSETo determine the change in stability of single-stage, three different design of implant systems in humans utilizing resonance frequency analysis for early healing period (24 weeks), without loading.MATERIAL AND METHODSTwenty-five patients were included into this study. A total of 45 implants, three different design of implant systems (group A,C,R) were placed in the posterior maxilla or mandible. The specific transducer for each implant system was used. ISQ (implant stability quotient) reading were obtained for each implant at the time of surgery, 3, 6, 8, 10, 12, 24 weeks postoperatively. Data were analyzed for different implant type, bone type, healing time, anatomical locations.RESULTSFor each implant system, a two-factor mixed-model ANOVA demonstrated that a significant effect on ISQ values (group A = 0.0022, C = 0.017, R = 0.0018). For each implant system, in a two-factor mixed model ANOVA, and two-sample t-test, the main effect of jaw position (P > .005) on ISQ values were not significant.CONCLUSIONSAll the implant groups A, C and R, the change patterns of ISQ over time differed by bone type. Implant stability increased greatly between week 0 and week six and showed slow increase between week six and six months (plateau effect).