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Introduction: The phone's sound beams are known to be a valid test that reflects the activity of foreign hair cells, and are therefore very useful for assessing cochlear changes, such as those that occur after exposure to noise.
method: In one clinical trial, 74 volunteers aged 18-25 were examined by simple random sampling. The results of audiometric tests of the participants' pure sounds and tympanometry were within the norm on the day of the experiment. In this study, the phonetic tests of the phone were spontaneous, transient, and distorted from both ears of the subject, which was considered as a basic level of evaluation for us. Then a person's ear was selected and in the intensity of SPL 100 decibels and for 5 minutes in his ear was given a turn. After 2 minutes after the end of the presentation, the previous evaluations were repeated in both ears and the range of responses in both ears was compared.
Results: In 34 participants, submucosal nostrils led to a decrease in amplitude or SOAE responses. One of the interesting findings in this study was the emergence of new peaks in SOAE responses in the opposite ear after the presentation of the sound. The proposed noise created a significant statistical decrease in the range of TEOAE response both in the affected ear and in the opposite ear. Comparing the mean amplitude of DPOAE responses before and after exposure to shift-induced noise in the ear was significant in the Hertz range of 1699-6299, but this comparison was not significant in the opposite ear. The mean time of DPOAE incubation before and after exposure to shingles did not show a statistically significant difference in both the affected ear and the opposite ear.
Conclusion: The findings show that the phone's sound beams are a good tool for tracking hearing damage caused by noise. TEOAEs are also more sensitive to tracking than other tests, and can even be used as a very fast screening tool to assess susceptibility to hearing damage caused by noise before entering high-end industrial environments. And considered sound.

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Background: Noise-induced hearing loss is a noticeable clinical issue. The aim of this study was to evaluate the effect of N-Acetylcysteine on the reduction of permanent noise-induced hearing loss in workers at Hepco Company. Materials and Methods: In this clinical trial, in a one-month period from October to November, 118 male 22-52 year-old workers with at least 5 years of experience working in places with permanent high tone noise (more than 850db) were selected and divided to experimental and control groups. The experimental group received Fluimucil (NAC) and the control group received vitamin B1. Hearing ability of the two groups was evaluated through audiometry after the one-month period. Results: In the control group, hearing loss was significant and it was in direct relationship with age and job experiment. The placebo (vitamin B1) did not have any significant effects on preventing hearing loss. In the experimental group, there was significant hearing loss in higher frequencies and at 6000, a relative improvement was observed, whereas with increases in age and job experience hearing loss became more significant which was rather low in comparison with the control group. Conclusion: The findings of this study shows that using N-Acetylcysteine has significant effects on NIHL (high tone loss) in higher frequencies. This study can be used as the basis for launching future studies on reducing the damages induced by noise

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Background: The aim of this study was to assess the effect of training, and noise stress on serotonin plasma level of Wistar rats.

Materials and Methods: For many years, physical activity have been used for the treatment of different neuropsychological dieases. Twenty one male witar rats (9-10 weeks old and 170.82±20.57g weight) were randomly divided into three groups: the noise group (n=7), training+noise group (n=7), and the control group (n=7). The aerobic training was performed 5 days per week, for a 60-day period. The noise stress included exposure to traffic noise 5 hrs/per day over a 60-day period (range:85-110 dB).The control group was not exposed to any noise or exercise, and was kept away from the sources of stress the rats were kept under the same conditions. At the end of the experiment, blood samples were collected and plasma serotonin concentrations were determined.For the statistical data analysis, one-way ANOVA and Tukey post-hoc tests were used (&alpha&le0.05).

Results: Plasma serotonin concentration significantly decreased in noise groups, in comparison with the controls (21.9±2.1, vs.40.8±7.3 &mumol/m, respectively p<0.000). The plasma serotonin levels in the noise +training groups (36.2±3.1) were apparently near to the controls However, resistance training could significantly increase plasma serotonin concentration in the noise+training group rats.

Conclusion: Increased serotonin level following resistance exercises might reduced stress in subjects.

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Background: Electrocardiogram signal (ECG) is a graphical representation of the heart activity. Processing and analysis of these morphological changes can result in visual diagnosing some cardiac diseases. However, various types of noises and disturbances in ECG influence the visual recognition and feature extraction from it. The aim of this research is to eliminate different noises from ECG and to enhance its quality.

Materials and Methods: In this study, an adaptive Kalman filter is developed by using Bayesian model. Considering simplification and Gaussian distribution for measurement noise, complicated mathematical equations were converted to simple relations and therefore implementation was simplified.

Results: In this paper, by designing an adaptive Kalman filter, the signal to noise ratio (SNR) has increased to 21.46dB. Adaptive Kalman filter based on Beyesian framework could model dynamic variations of ECG signal by estimating covariance matrix for measurement noise.

Conclusion: In despite of Kalman filters that use parametric functions to model ECG signal, the adaptive Kalman filter introduced in this paper uses real ECG records for modeling. Parametric functions which could model dynamic variations of ECG need a lot of analytical functions and this decreases the time of filtering process but the adaptive Kalman filter proposed in this research has a high speed and could be used in real time applications.