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Öğe A comparison of the generation of free radicals in saliva of active and passive smokers(Tubitak Scientific & Technological Research Council Turkey, 2014) Demirtas, Murat; Senel, Unal; Yuksel, Sevda; Yuksel, MustafaAim: To reveal any correlation between cigarette smoke and malondialdehyde (MDA) values in the saliva fluid of subjects who are active smokers or nonsmoking subjects who are exposed to cigarette smoke in their environments. Materials and methods: Saliva samples were taken from 3 groups: a control group (group 1), a group inhaling smoke passively (group 2), and a test group (group 3) smoking 20 cigarettes per day; each group consisted of 20 members, giving a total sample of 60 people, aged 20 to 45 years. MDA, which is an indicator of lipid peroxidation, was measured via the colorimetric method. Results: Salivary MDA levels in smokers were found to be significantly higher compared to the control group and the group of passive smokers (P < 0.05). When compared with the control group, the MDA levels of passive smokers and active smokers were higher; when passive and active smokers were compared, the MDA levels of active smokers were higher. When all 3 groups were compared, the MDA levels in the control group (nonsmokers) were observed to be lower than the MDA level of the other 2 groups. Conclusion: It was observed that lipid peroxidation, which is an indicator used to determine oxidative stress, and MDA level, which is a product of this reactive chain, are significantly higher in individuals who are smokers. Such a high level of MDA in passive smokers indicates that smoking also affects nonsmokers negatively.Öğe A novel approach to enhancement of surface properties of CdO films by using surfactant: dextrin(Taylor & Francis Ltd, 2015) Sahin, Bunyamin; Bayansal, Fatih; Yuksel, MustafaWe studied the effect of an organic surfactant, dextrin, concentration on structural, morphological and optical properties of nanostructured CdO films deposited on glass substrates by using an easy and low-cost SILAR method. Microstructures of the nanostructured CdO films were optimized by adjusting dextrin concentration. XRD, SEM and UV-Vis Spectroscopy were used to study phase structure, surface morphology and optical properties of CdO films. Furthermore, effects of dextrin concentration on the surface roughness characteristics of CdO samples were reported. The results showed that the presence of organic surfactant highly affected the physical properties of CdO nanomaterials.Öğe Capacitive solvent sensing with interdigitated microelectrodes(Springer, 2016) Bilican, Ismail; Guler, Mustafa Tahsin; Gulener, Neset; Yuksel, Mustafa; Agan, SedatWe were able to quantify dielectric properties of solvents such as DI water, isopropyl alcohol, and acetone using interdigitated microelectrodes (IMEs). IMEs were fabricated using conventional micro fabrication techniques. The fabricated IMEs were dipped into the solution, and the dielectric property of the medium was measured. A range of frequencies and excitation voltages were swept in order to determine the operation region that yields the highest signal to noise ratio. Measurements were performed at 1 MHz and 100 mV which resulted in best signal to noise ratio. We applied a simple analytical model for the calculation of the capacitance and measured the capacitance value using a simple parallel capacitor and resistor model which resulted in perfect agreement with theoretical results. The presented sensor provides a simple and accurate method to determine solvent type which may have possible future applications.Öğe Evaluation of Acoustic Reflex and Reflex Decay Tests in Geriatric Group(Galenos Yayincilik, 2016) Unsal, Selim; Karatas, Havva; Kaya, Mesut; Gumus, Nebi Mustafa; Temugan, Esra; Yuksel, Mustafa; Gunduz, MehmetObjective: To determine average acoustic reflex thresholds in geriatric groups by assessing ipsilateral and contralateral acoustic reflex and reflex decay tests. Methods: A total of 25 elders between ages 65-84 years (74.3 +/- 5.4) and 25 individuals between ages 18-45 years (30.4 +/- 4.2) were recruited for the study. After ear, nose, and throat examination, ipsilateral and contralateral acoustic reflex thresholds at 500, 1000, 2000, and 4000 Hertz (Hz) were determined and a reflex decay test at contralateral 500 Hz was conducted. Ipsilateral acoustic reflex thresholds were obtained with high-frequency band, low-frequency band, and wide band noise, and the results were compared with ipsilateral acoustic reflexes at 500, 1000, 2000, and 4000 Hz. Results: There was no statistically significant difference between the two groups in ipsilateral and contralateral acoustic reflex measurements at 500, 1000, 2000, and 4000 Hz (p>0.05). Negative reflex decay was obtained in all participants and no statistically significant difference between the two groups was observed in terms of reflex decay thresholds (p>0.05). Acoustic reflex with high-frequency band noise was observed in five of nine elders whose acoustic reflexes were not obtained at 2000 and 4000 Hz, whereas acoustic reflex with low-frequency band noise was observed in one of six elders who did not show reflexes at 500 and 1000 Hz. Conclusion: It was concluded that although some changes were observed due to age, middle ear and stapes muscles work normally in geriatric group. In the reflex decay test, reliable results were obtained at contralateral 500 Hz. Acoustic reflex measurements with low-and high-frequency band noise may also be used to assess middle ear functions.Öğe EVALUATION OF EUSTACHIAN TUBE FUNCTION TESTS AND IMMITANCEMETRIC MEASUREMENTS IN A GERIATRIC GROUP(Gunes Kitabevi Ltd Sti, 2016) Unsali, Selim; Yaman, Unzile; Gumus, Nebi Mustafa; Kaya, Mesut; Temugan, Esra; Gecin, Mustafa Vecdi; Yuksel, MustafaIntroduction: Atrophy in the middle ear and degeneration of muscle fibers, fibrous tissue ligament, and bone as well as calcification of Eustachian cartilage occurs with aging. We aimed to evaluate the middle ear system and changes in Eustachian tube functions in a geriatric group. Materials and Method: Study participants comprised 30 older and 30 younger individuals between the age of 65 and 84 years (74.3 +/- 5.4 years) and 18 and 45 years (30.4 +/- 4.2 years), respectively. All participants underwent immitancemetric measurements and Eustachian tube function tests after ear, nose, and throat examination. For the immitancemetric measurements, the ear canal volume, compliance, middle ear pressure, and gradient were evaluated. Valsalva and Toynbee maneuvers were used to perform the Eustachian tube function tests. Results: Non-significant differences were found between the two groups for the ear canal volume and middle ear pressure (p>0.05). While no significant difference was found for the left ear compliance values between the two groups (p>0.05), a significant difference between the left ear compliance and gradient values for both ears was found (p<0.05). Eustachian tube function tests showed no significant differences between the groups, based on the values obtained by Valsalva and Toynbee maneuvers. Conclusion: Eustachian tube functions in the geriatric group were found to be normal in this study. Bilateral gradient and right ear compliance values were higher in the geriatric group than in the control group indicating that the middle ear system in the geriatric group was more active.Öğe Examination of Insert Ear Interaural Attenuation (IA) Values in Audiological Evaluations(Canadian Soc Clinical Investigation, 2016) Gumus, Nebi M.; Gumus, Merve; Unsal, Selim; Yuksel, Mustafa; Gunduz, MehmetPurpose: The purpose of this study was to evaluate Interaural Attenuation (IA) in frequency base in the insert earphones that are used in audiological assessments. Methods: Thirty healthy subjects between 18-65 years of age (14 female and 16 male) participated in our study. Otoscopic examination was performed on all participants. Audiological evaluations were performed using the Interacoustics AC40 clinical audiometer and ER-3A insert earphones. IA value was calculated by subtracting good ear bone conduction hearing thresholds of the worst airway hearing threshold. Results: In our measuring for 0.125-8.0 kHz frequency were performed in our audiometry device separately for each frequency. IA amount in the results we found in 1000 Hz and below frequencies about 75-110 dB range avarage is 89 +/- 5dB, in above 1000 Hz frequencies in 50-95 dB range and avarage it is changed to 69 +/- 5dB. Conclusion: According to the obtained findings the quantity of melting in the transition between the ears are increasing with the insert earphones. The insert earphone should be beside supraaural earphone that is routinely used in clinics. Difficult masking applications due to the increase in the value of IA can be easily done with insert earphones.Öğe Preparation and Characterization of Zn x Cu(1-x)O Composite Films on Glass Substrates Through SILAR Processing(Springer, 2015) Bayansal, Fatih; Sahin, Bunyamin; Yuksel, MustafaCuO composite thin films with and without Zn-doping are deposited onto glass substrates by the SILAR method. All the films are characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), UV-Vis spectrophotometry, temperature dependent dc conductivity, and X-ray diffraction (XRD) measurements. SEM results show that the particle size decreases from 27 to 16 nm with increasing Zn-doping. EDX analysis evidences the amount of Zn in CuO films, which increases with increasing Zn concentration in the growth solutions. Transmittance, optical band gap, and activation energy values of the films are found to be increasing from the UV-Vis and temperature dependent dc conductivity measurements with increasing Zn-doping. It also is found from the XRD patterns that mean crystallite size of the films decreases from 18.94 to 13.70 nm with increasing Zn-doping. Moreover, increase in Zn concentration results peak shifts to lower 2 theta values. (C) The Minerals, Metals & Materials Society and ASM International 2015Öğe Retrospective air bone gap evaluation of patients with tympanic membrane central perforation(Canadian Soc Clinical Investigation, 2016) Kucukkavruk, Levent; Temugan, Esra; Kaya, Mesut; Unsal, Selim; Gumus, Nebi Mustafa; Yuksel, Mustafa; Gunduz, MehmetPurpose: The purpose of this study was to evaluate hearing recovery and air-bone gap (ABG) before and after tympanoplasty surgery in patients with tympanic membrane central perforation. Methods: Histories and audiological assessments of 160 cases (total of 26 ears from 22 patients; 11 men and 11 women) from patients who had undergone tympanoplasty surgery and hearing reconstruction due to tympanic membrane central perforation were evaluated. Pre-postoperative audiograms and the pure tone, air-bone hearing thresholds and ABG gains were evaluated. Results: The mean age of the patients was 38.6 years (+/- 16.04). The mean postoperative follow-up period was 13.4 months (+/- 15.5). The mean preoperative ABG was 25.36 dB (+/- 9.9) and postoperative ABG was 17.36 dB (+/- 11.68) (p = 0.001). When four groups were compared before surgery and after surgery period as 0-6 months, 6-12 months, 1-2 years and 2 years in terms of pre-and postoperative ABG values, no statistically significant difference was observed (p>0.05). All patients were divided into three groups: < 20 years of age; between the ages of 21-40; and, > 41 years of age, and no statistically significant difference were found between the groups (p>0.05). Surgeries of the patients 21-40 years of age were more successful (ABG gain) than other age groups. No statistically significant gender differences were found in ABG averages (p = 0.33), but clinical results were significantly better in women as compared with men. Conclusion: In patients with central tympanic membrane perforation, tympanoplasty surgery with temporal fascia is beneficial in terms of hearing recovery.Öğe THE EFFECT OF DIFFERENT TURKISH SONG COMPOSITIONS ON THE SYMPATHIC AND IMMUNOBIOCHEMICAL PARAMETERS(Nobel Ilac, 2015) Yuksel, Sevda; Kazanci, Fatmanur Hacievliyagil; Ciftci, Sefa; Altan, Merve; Yuksel, Mustafa; Erdamar, Husamettin; Yigitoglu, RamazanObjective: Turkey is a rich country in musical heritage. Studies on the use of music for therapeutic purposes are increasing day by day. The Greek philosophers were convinced that music benefited health and specific recommendations were formulated for using music therapeutically against mental and physical illness. To evaluate the effects of different classical Turkish music styles (Saba, Muhayyer Kurdi, Hijaz, Ussak) on these parameters. Therefore we planned this research to accomplish all of these aims. Material and Method: Venous blood samples were collected before and after music listening and serum levels of serotonin, adrenalin, immunoglobulin A and cortisol were measured. Sixtyone healthy volunteers listened five different kinds of music (popular, rock, arabesque, European classical, classical Turkish music). Results: To compare the same parameters in each volunteer before and after music listening, the Wilcoxon signed-ranks were performed as appropriate. For tests of significance, a p-value of <0.05 was considered to be statistically significant. All parameters were normally distributed. Conclusion: Our Statistical analysis results showed that cortisol level of the people listening Saba style decreased, Immunoglobulin A level decreased for the people who listened popular music and increased for the group listening Nihavent style and adrenaline level increased significantly in all groups except for the people listening Ussak style of music.Öğe Using nanogap in label-free impedance based electrical biosensors to overcome electrical double layer effect(Springer, 2017) Okyay, Ali Kemal; Hanoglu, Oguz; Yuksel, Mustafa; Acar, Handan; Sulek, Selim; Tekcan, Burak; Agan, SedatPoint-of-care biosensor applications require low-cost and low-power solutions. They offer being easily accessible at home site. They are usable without any complex sample handling or any kind of special expertise. Impedance spectroscopy has been utilized for point-of-care biosensor applications; however, electrical double layer formed due to ions in the solution of interest has been a challenge, due to shielding of the electric field used for sensing the target molecules. Here in this study, we demonstrate a nanogap based biosensor structure with a relatively low frequency (1-100 kHz) measurement technique, which not only eliminates the undesired shielding effect of electrical double layer but also helps in minimizing the measurement volume and enabling low concentration (A mu molar level) detection of target molecules (streptavidin). Repeatability and sensitivity tests proved stable and reliable operation of the sensors. These biosensors might offer attributes such as low-cost label-free detection, fast measurement and monolithic chip integrability.
