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This study verified the efficacy of the intentional repetition technique in improving interaction in asynchronous online discussions by taking into account the learning styles of the participants. A conceptual framework served for the development of the technique, which conceptualises efficient and cohesive interaction on a continuum of process that move from social presence to production of an artefact. Sixty-one university students participated in the study. A quasi-experimental research design was used. The subjects, who were assigned randomly into two groups, were tested using Kolb's learning style inventory. The results showed that the experimental group exposed to the intentional repetition technique produced significantly better interaction than the control group, regardless of their learning styles, which had no significant effect on the interaction. Moreover, there was no interaction effect between the learning styles and the treatment. The implications arising from these results identify various suggestions for increasing the coherence and depth of the interaction amongst students in asynchronous online discussions. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effects of ozone in experimental acute sciatic nerve injury. Material and Methods: Twenty-eight male rats were divided into four groups (n = 7): control (C), ozone (O), injury (SNI), and treatment with ozone after injury (SNI + Ozone). Sciatic nerve injury was generated by compressing the right sciatic nerve for 90 s using a Yasargil aneurysm clip in groups SNI and SNI + Ozone. A 70 µg/ml concentration of ozone was given four times (once a day at 1st, 24th, 48th, and 72th h) at a dose of 0.5 mg/kg to groups O and SNI + Ozone after injury by an intraperitoneal injection. Nerve conduction velocities of all rats were measured by in vivo electrophysiological tests at the end of the day 4. Then, plasma malondialdehyde, total oxidant and antioxidant status were measured and also axonal and myelin changes in sciatic nerves of histopathological examination were performed. The data were analyzed by Kolmogorov Smirnov test, Mann–Whitney U-test, and Chi square test. p <.05 was considered statistically significant. Results: The proximal and distal latency difference were higher and nerve conduction velocity were lower in SNI group than C and O groups, and the myelin structure was found to be broken in group SNI compared to groups C and O. However, the amplitude of the compound action potential, the nerve conduction velocity were significantly higher in group SNI + Ozone than in group SNI. Moreover, myelin injury was significantly lower in group SNI + Ozone compared to group SNI. Total oxidant status in group SNI was significantly higher than in groups C, O, and SNI + Ozone. But, total antioxidant status in group SNI was significantly lower than in groups C, O, and SNI + Ozone. Conclusion: This study showed that the administration of ozone at a dose of 0.5 mg/kg after peripheral nerve injury in rats reduces myelin and axonal injury. [ABSTRACT FROM AUTHOR]

Objective: Although, the neuroprotective effects of selenium are known, its effect on peripheral nerve injury is not clear. The study was aimed to investigate whether selenium prevents axonal and myelin damage in experimental sciatic nerve injury. Materials and Methods: Twenty-eight male Wistar albino rats were divided into four groups (n=7 in each): control (C), selenium (S), injury (I), and selenium-treated injury (SI). Injury was generated by 30 second of compression via Yasargil aneurysm clip on the sciatic nerve of rats in the I and SI groups. Then, selenium was given to the S and SI groups as 1.5 mg/ kg by oral gavage at 1st, 24th, 48th and 72ndhour after surgery. According to the experimental protocol, electrophysiological, histological, and biochemical tests were performed end of the day 4. Results: Whereas the amplitude of compound action potential, nerve conduction velocity, average axon diameter, myelin thickness, myelinated/unmyelinated axons and SOD activity in red blood cells of the I group were significantly lower than those of the C, S and SI groups, the serum MDA levels of the I group were significantly higher than those of the C, S and SI groups. Conclusion: The findings of this study show that selenium decreases axonal and myelin damage after sciatic nerve injury and that this neuroprotective effect of selenium is at least partially mediated by oxidant/antioxidant mechanisms. [ABSTRACT FROM AUTHOR]