مطالب

Previous studies have demonstrated the efficacy of speech rhythm measures in speaker identification across various languages with different phonotactic structures. In Persian language, in particular, two categories of speech rhythm metrics were examined: duration-based and intensity-based metrics. Building upon these prior works, the current study delves deeper into the discrimination capabilities of the mentioned measurement types—duration-based versus intensity-based—in the context of Persian speakers. To achieve this, a multinomial logistic regression model was employed on a dataset comprising 20 male Persian speakers, each reciting 100 sentences at a normal speaking pace. Findings revealed that, when distinguishing between Persian speakers, duration-based measures outperform intensity-based ones, however, this excellence is very slight. This observation is significant, as it sheds light on the suitability of specific rhythm metrics for Persian speaker identification. I postulate that this discrepancy in performance may be attributed to the simple syllable structure of Persian and the lesser reliance on intensity as a primary indicator of lexical stress. This research contributes valuable insights into the choice of rhythm metrics for optimal Persian speaker identification and underscores the importance of considering linguistic features when developing speaker recognition systems.Top of Form

Background: Perturbation training which is in the context of volleyball routine practice is a type of neuromuscular exercises that is useful in overhead sports; leads to contraction responses through unpredictable perturbation. Aim : The present study aims to investigate the effects of perturbation training on volleyball players strength proprioception and performance. Materials and Methods: Twenty-four volunteer male volleyball players (age: 24.42±2.15 years; height: 181.46±3.00m; Weight: 73.87±3.77kg; BMI: 22.43±0.80) were recruited and randomly assigned into perturbation and control groups, Before the intervention, a set of isokinetic dynamometry was carried out to measure shoulder proprioception as well as rotator cuff muscles strength, what is more, the upper extremity performance was evaluated using Y-Balance Test. For a course of 6 weeks, players of the perturbation group implemented perturbation trainings, 3 times weekly while the control group performed its routine training. The dynamometry was repeated at the end of training period to compare trainings outcome. The Repeated Measures ANOVA statistic was used to find differences between groups. Results: A significant difference in shoulder proprioception, as well as the YBT-UQ test, was observed between the groups; Also, the ANOVA showed a significant difference ( P <0.05) in functional strength ratio followed by 6 weeks of perturbation training. Conclusion: Perturbation trainings might have benefit to volleyball players conditioning by improvement rotator cuff strength, shoulder proprioception and upper extremity performance. Given this adopting kind of training as a part of regular basic training for volleyball players is highly recommended.

Background: Transcranial alternating current stimulation (tACS) is a non-invasive method that offers a potential solution to reduce the effects of aging on brain function. Aim: The aim of this study was to investigate the effect of offline tACS over the supplementary motor area on bimanual coordination in elderly people. Materials and Methods: Thirty-one women aged of 60-75 years were selected as convenience. They were assigned to 2 conditions: tACS and Sham, in random order, with one-week interval between conditions. After pre-test, each participant completed four trials of 5 min using Purdue pegboard task. Concurrently, participants received beta tACS with a current intensity of 1 mA. Immediate retention test, transfer test, and delayed retention tests after 48 hours and 1 week were conducted. A 2(condition) x 4(test) ANOVA with repeated measures was performed on gain scores. Results: The main effects of condition and test were significant ( P <0.0001). The Bonferroni tests revealed the significant improvement of bimanual coordination in the tACS condition compared to the sham condition in all retention and transfer tests ( P <0.05). Conclusion: The findings highlights the potential use of offline beta tACS over the SMA as a modulatory factor for enhancing bimanual coordination in the elderly women.