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Optical second-harmonic generation (SHG) is a noninvasive technique that provides information about interface properties and crystal defects. This article demonstrates the use of SGH in the study of high-k dielectrics, silicon-on-insulator structures, compound semiconductors, and through-silicon vias.

BACKGROUND: One of the most prevalent side effects of hemodialysis is intradialytic hypotension and its symptoms. Using sodium profiles 3 and ultra filtration profile 3 and cold dialysate are the ways to overcome this problem. Since none of these methods could control this complication lonely, this study was done to investigate the effect of combination of two methods on intradialytic hypotension. METHODS: This study was a cross over clinical trial in which 24 patients experienced intradialytic hypotension frequently, underwent three different methods of treatments during 9 successive hemodialysis sessions, group 1 used sodium profile 3 and ultra filtration profile 3, group 2 underwent hemodialysis with cold dialysate, and group 3received combination of both methods. Blood pressure was controlled before, during (3 times) and after hemodialysis. Data were analyzed via SPSS version 15, using x2 and ANOVA test. RESULTS: Findings showed that although there was no significant difference considering intradialytic hypotension and its symptoms in two groups of sodium profile 3 and ultra filtration profile 3 and cold dialysate and the combination group (p > 0.05), but there was a significant difference considering the mean of blood pressure in three groups (p < 0.05). In combination group, drop of systolic and diastolic blood pressure was less than groups using each of methods. CONCLUSIONS: Concerning the decreased rate of hypotension using combination method, nurses can use this method to decrease intradialytic hypotension and help the patients undergo hemodialysis for enough time and improve their quality of life.

Background: Considering the possibility of remaining bacteria in the cavity or invading via microgaps, the use of antibacterial agents in adhesive restoration may be beneficial. This study evaluated the effect of chlorhexidine on immediate and long-term shear bond strength of adhesives with and without antibacterial agent to dentin. Materials and Methods: In this in vitro study, the occlusal surfaces of 80 intact human premolars were removed to expose the flat midcoronal dentin. The teeth were assigned to four groups. Two adhesive systems, Clearfil SE Bond (SE) and Clearfil Protect Bond (PB) were used according to manufacturer′s instructions as the control groups. In the experimental groups, 2% chlorhexidine was applied prior to acidic primer of two adhesives. Then, resin composite was applied. Half of the specimens in each group were submitted to shear bond test after 24 h without thermocycling, and the other half were submitted to water storage for 6 months and thermocycling before testing. The data was analyzed using three-way analysis of variance (ANOVA) and t-test (α = 0.05). Results: Chlorhexidine application significantly decreased the initial bond strength (BS) of the two self-etch adhesives to dentin (P < 0.05). There was a significant reduction in BS of SE and PB after aging compared to initial bonding (P < 0.05). However, there was no significant difference between BS of the control and chlorhexidine-treated groups for the tested adhesives after aging. PB showed a lower BS than SE in two time periods (P < 0.05). Conclusion: Chlorhexidine was capable of diminishing the loss of BS of these adhesives over time. However, considering the negative effect of chlorhexidine on the initial BS, the benefits of chlorhexidine associated with these adhesives cannot possibly be used.