Can Dentin Surfaces Be Bonded Safely With Ozone and Boric Acid?

The aim of this study is to evaluate the effect of different cavity disinfectants on shear bond strength. In this study, 60 caries-free human molar teeth were used. Smooth dentin surfaces were revealed by cutting occlusal enamel and a standard smear layer was obtained by using 600-grid sandpaper. Specimens were randomly assigned to four groups according to the disinfectant used: Group 1: Control (no disinfectant); Group 2: Ozone; Group 3: Chlorhexidine, Group 4: Boric acid. Specimens were bonded using S3 Plus Bond and the composite buildups were created by using composite resin according to the manufacturer’s instructions. After specimens were kept for 24 h, at 37 °C in distilled water, the shear bond strength test was measured with a universal test machine. The highest bond strength values were observed in the control group. The bond strength was significantly lower in the chlorhexidine, and boric acid-treated groups than it was in the control group (respectively, p = 0.046 and p = 0.028); however, no significant difference in the bond strength was observed between the ozone group and the control group (p = 0.444). The ozone group was detected as having the best shear bond strength values in groups which were applied to cavity disinfectants.     

Phenolic Content and Antioxidant Activity of Raspberry and Blackberry Cultivars

ABSTRACT: Raspberry (Aksu Kırmızısı, Rubin, Newburgh, Hollanda Boduru, Heritage) and blackberry (Bursa 1, Bursa 2, Jumbo, Chester) cultivars were assayed for antioxidant activity (determined as 2,2-azino-di-[3-ethylbenzothialozine-sulphonic acid][ABTS], 2,2-diphenyl-1-picrylhydrazyl radical [DPPH], and cupric ion reducing antioxidant capacity [CUPRAC]), total phenol, total flavonoid, and total anthocyanin contents. In addition, 10 anthocyanins and anthocyanidins were determined in raspberry and blackberry by liquid chromatography-mass spectrometry (LC-MS/MS). Raspberry and blackberry had the highest ABTS, DPPH, CUPRAC, total phenol, and total flavonoid contents in methanol extracts, whereas total anthocyanin contents were the highest in water extracts. The antioxidant activity of the raspberry and blackberry was directly related to the total amount of phenolic compounds detected in the raspberry and blackberry. All antioxidant activity values were highly correlated with anthocyanin content in blackberry (0.93 ≤ r ≤ 0.99, P = 0.05). On the other hand, high correlation between total flavonoid content and antioxidant activity was recorded in water extract of blackberry (0.91 ≤ r ≤ 0.93, P = 0.05). ABTS value was highly correlated with total flavonoid content in methanol extract (r = 0.90), whereas total flavonoid content was relatively less correlated with DPPH (r = 0.85) and CUPRAC (r = 0.89).     

The effect of the amine structure on photoinitiated free radical polymerization of methyl methacrylate using bisketocoumarin dye

Photoinitiation of the polymerization of methyl methacrylate by the bis-diethylaminocoumarin dye (BKC) in the presence of various amines was studied in order to determine the efficient amine that leads to the formation of the initiating radicals. RT-FTIR studies were also performed for multifunctional methacrylate. According to photoinduced polymerization and RT-FIR studies, N-methyldiethanol amine was the more efficient H-donor compared with the others.     

Collaboration networks of arab biomedical researchers

Social networks (SN) consist of a set of actors and connections between them. A collaboration network (ColNet) is a special type of SN, in which the actors represent researchers and the link between them indicate that they have co-authored at least one paper. ColNet analysis reveals how researchers interact and behave. A wide range of applications can be based on such studies. The current works on ColNet usually focus on a specific domain/discipline, country/geographical region or time interval. In our study, we focus on one of the understudied regions (the Arab world), and present a novel study on the ColNet of researchers in this region. The domain of interest in our study is biomedicine. We construct, analyze, and study ColNet of biomedical researchers in the Arab world. We divide the region of interest (the Arab world) into four geographical regions and look into the evolution of ColNet of each region separately over time. Our analysis reveals that there is an increase in the number of both authors and publications over time, and that authors tend to work in increasingly larger groups rather than working individually, which is consistent with what is assumed about the nature of research in this field. Our analysis also reveals that a researcher’s productivity is correlated with the amount of change in his/her circle of collaborators over time. For example, researchers working in stable or fixed groups and researchers who have completely different research group every few years are not necessarily the most productive ones.

     

Multiple Regression Analysis of Catalytic Dehydrogenation of Isopropanol in a Chemical Heat Pump System

Chemical heat pump is a clean technology developed to upgrade the low‐level thermal energy to upper levels and to store energy without losses caused by temperature differences. Multiple regression analysis of catalytic dehydrogenation of isopropanol was performed. The endothermic dehydrogenation of isopropanol was carried out under continuous boiling and refluxing conditions in order to study the enhancement effects of the presence of an alkaline compound and different types of catalysts at various concentrations in the reaction medium on the evolution rate of hydrogen. The factorial experimental design method was applied to understand better the coupled influences of both catalyst and alkaline additive concentrations to discuss and evaluate statistically the results for different catalysts and to develop the related models.     

Experience with continuous venovenous hemodiafiltration in four newborns: A case series and review of the literature

When conventional methods for treating complicated problems such as acute and chronic renal failure or metabolic diseases fail, the therapy of choice is peritoneal dialysis (PD) in neonatal period. However, in cases that involve technical difficulties, such as bulky lesions in the abdomen or complications from previous abdominal surgeries, it is not always possible to place a peritoneal catheter. In such situations, continuous venovenous hemodiafiltration (CVVHDF) can be effective. This case series presents our experience in 2013 with the administration of CVVHDF to four patients in our neonatal intensive care unit who could not undergo PD for various reasons.