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Background and Objectives The most common cause of snoring in children is enlarged tonsils and adenoids. However, there is insufficient evidence to determine whether the subjective measurement of tonsil hypertrophy, the most common prevailing method, reflects the actual tonsil size and volume. Therefore, we tried to determine whether the subjective grading of tonsil size and actual tonsil volume is related, and whether tonsil volume, weight, and adenoid index are correlated with the acoustic analysis of snoring.Subjects and Method The study was conducted on 21 children between the ages of 4 and 15 who came for tonsillectomy and adenoidectomy due to snoring symptoms. The degree of adenotonsillar hypertrophy was measured using the Brodsky grading scale and adenoid index. After tonsillectomy, the volume and weight of resected tonsil were measured. For acoustic analysis, the Praat software was used to determine formant frequency and sound intensity. A linear regression model and a dummy variable were used to determine the correlation between the quantitative values of tonsil, adenoid and the result of acoustic analysis.Results The Brodsky tonsil grade tended to match the actual tonsil volume, but it was not statistically significant (p=0.073). There was no correlation between snoring intensity and actual tonsil volume, weight, and adenoid index. Formant frequency 1 and 2 were statistically negatively correlated with the actual tonsil volume (p=0.011, 0.002).Conclusion The study confirmed that the acoustic analysis of pediatric snoring could be a screening test to predict tonsil volume and changes in the vocal tract due to tonsil hypertrophy.

Summary Objective The aims of this study were to (1) to determine the cut-off values of parameters related to auditory perceptual assessment (visual analog scale) and acoustic analysis (cepstral peak prominence, low frequency/high frequency ratio, cepstral peak prominence standard deviation, low frequency/high frequency ratio standard deviation, acoustic voice quality index, and cepstral spectral index of dysphonia) for predicting the voice severity within a Korean population; and (2) to verify the discriminative power of these cut-off values. Methods Voice samples of 1,029 subjects who visited Pusan National University Hospital, South Korea to be treated for swallowing or voice evaluation from January 2018 to December 2018 were analyzed in this retrospective study. The acoustic analysis of cepstral parameters, cepstral spectral index of dysphonia, and acoustic voice quality index were calculated using the Computerized Speech Lab and Praat software. The cut-off values of parameters predicting the voice severities were obtained using receiver operating characteristic analysis. Through this analysis, the sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were measured. Results High reliabilities of auditory perceptual assessments were observed for the auditory perceptual assessment. The cut-off values of parameters predicting voice severities had high sensitivity, specificity, and area under the curve. Conclusions The cut-off values of parameters predicting the voice severities demonstrated a high power to discriminate for classifying the voice severities within a Korean population. The results of this study could be used as objective criteria to screen for severities of voice disorders.

Several studies have been performed using recently developed smartphone-based acoustic analysis techniques. We investigated the effects of septoplasty and turbinoplasty in patients with nasal septal deviation and turbinate hypertrophy accompanied by snoring by recording the sounds of snoring using a smartphone and performing acoustic analysis. A total of 15 male patients who underwent septoplasty with turbinoplasty for snoring and nasal obstruction were included in this prospective study. Preoperatively and 2 months after surgery, their bed partners or caregivers were instructed to record the snoring sounds. The intensity (dB), formant frequencies (F1, F2, F3, and F4), spectrogram pattern, and visual analog scale (VAS) score were analyzed for each subject. Overall snoring sounds improved after surgery in 12/15 (80%) patients, and there was significant improvement in the intensity of snoring sounds after surgery (from 64.17 ± 12.18 dB to 55.62 ± 9.11 dB, p = 0.018). There was a significant difference in the F1 formant frequency before and after surgery (p = 0.031), but there were no significant differences in F2, F3, or F4. The change in F1 indicated that patients changed from mouth breathing to normal breathing. The degree of subjective snoring sounds improved significantly after surgery (VAS: from 5.40 ± 1.55 to 3.80 ± 1.26, p = 0.003). Our results confirm that snoring is reduced when nasal congestion is improved, and they demonstrate that smartphone-based acoustic analysis of snoring sounds can be useful for diagnosis.

Background and Objectives Snoring is the most common symptom of obstructive sleep apnea (OSA) and is caused by turbulent airflow due to narrowing of the upper airways. In patients with positional OSA, a change in sleep posture from supine to lateral is known to reduce snoring and sleep apnea. This study was performed to compare changes in snoring sound intensity and formant frequencies according to sleep position.Subjects and Method A total of 19 patients (male: 18; female: 1) diagnosed with positional OSA by polysomnography (PSG) were enrolled in this study. The snoring sounds recorded during PSG were analyzed acoustically and compared according to sleep position (i.e., supine vs. lateral).Results Snoring disappeared on changing sleep position in five patients, all of whom had Apnea-Hypopnea Index (AHI)

Background and Objectives The purpose of this study was to investigate the effect of unvoiced segments on the cepstral analysis in patients with vocal cord paralysis (VCP).Subjects and Method A total 302 subjects (173 subjects with VCP and 129 normal voice subjects) participated in this study. The sustained vowel /a/ 2 seconds and one sentence of ‘Sanchaek’ were edited, and analyzed by Praat script. The cepstral analyses were performed using sustained vowel (SV), continuous speech (CS), and extracted continuous speech (EXT) samples. The auditory-perceptual (AP) rating was also completed by three raters.Results First, there were significant differences in all variables except low-to high spectral ratio(L/H ratio)_EXT between two groups. Second, cepstral peak prominence (CPP), smoothed cepstral peak prominence (CPPS), and L/H ratio showed significant differences in SV, CS, and EXT samples. Third, cepstral measurements were highly correlated with the AP ratings. Finally, the level of discrimination of dysphonia estimated from CPP and CPPS gotten from SV and CS values was more than area under the curve (AUC) of 0.941. AUC of 0.880 or more was also found in EXT.Conclusion In this study, we confirmed that both CS and EXT are highly predictive of pathologic speeches. Further study will also need to be validated for a more diverse group of voice disorders.

Summary Objective Although laryngeal videostroboscopy is widely utilized in the analysis of vocal fold vibrations, it is often difficult to identify patterns of vocal fold vibrations in patients with aperiodic voice signals due to failure of synchronization during laryngeal videostroboscopy examination. Therefore, the present study aimed to compare the usefulness of simultaneous two-dimensional digital kymography (2D DKG) and traditional DKG for the detection of changes in the pattern of vocal fold vibrations in patients with vocal fold scarring (VFS). Methods Seven patients with VFS and one normal subject underwent high-speed videoendoscopy (HSV). DKG and 2D DKG evaluations of vocal fold vibrations were performed simultaneously, following which both qualitative and quantitative analyses were performed. Results Simultaneous DKG and 2D DKG enabled observation of vibratory patterns as well as amplitude and phase symmetry. DKG revealed and provided temporal information regarding the pattern of vocal fold vibrations at sites of VFS. In contrast, 2D DKG provided real-time information regarding the pattern of vibrations for the whole vocal fold region and regions of increased stiffness, as well as spatial information regarding changes in this pattern. Conclusion Our findings indicate that 2D DKG enables the assessment of overall vocal fold vibrations, regardless of periodicity, and that simultaneous DKG and 2D DKG can be used to confirm abnormal patterns of vocal fold vibrations in patients with impaired flexibility and elasticity of the vocal folds.

Objectives The purpose of this study was to explore the effects of injection laryngoplasty (IL) with hyaluronic acid in patients with vocal fold paralysis (VFP). Methods A total of 50 patients with VFP participated in this study. Pre- and post-IL assessments were performed, which included analyzing the sustained vowel /a/ phonation, and the patient reading 1 Korean sentence from the "Walk" passage that comprised 25 syllables in 10 words. To investigate the effect of IL on vocal fold function, acoustic analysis (acoustic voice quality index, cepstral peak prominence, maximum phonation time, speaking fundamental frequency) was conducted and auditory-perceptual (grade and overall severity), visual judgment (gap), and self-questionnaire (voice handicap index-10) assessments were performed. Results The patients with VFP showed statistically significant differences between pre-and post-IL assessments for acoustic and auditory-perception, visual judgment, and self-questionnaire assessments. Conclusion The patients with VFP showed positive change in vocal fold function between pre- and post-IL measurements. The findings showed that IL with hyaluronic acid is an effective method to improve vocal fold function in patients with VFP.

Objectives The purpose of this study was to the usefulness of a five-variable model predicting perceived voice severity and incorporating acoustic analysis based on cepstral analysis and self-reported questionnaires, for measuring voice recovery after endolaryngeal phonomicrosurgery in patients with vocal fold polyps. Methods In this study, 72 patients with vocal fold polyps were included. Two voice evaluations, including acoustic analysis, self-reported questionnaires, and auditory perceptual assessments for each patient, were implemented before and after endolaryngeal phonomicrosurgery. Using these evaluations, we compared the mean values of the perceptual evaluation of voice, acoustic analysis parameters, self-reported questionnaires, and the five-variable model estimated severity pre- and post-endolaryngeal phonomicrosurgery. Results Various parameters related to acoustic analysis, self-reported questionnaires, and auditory perceptual assessments were useful for measuring voice recovery after endolaryngeal phonomicrosurgery. In particular, a five-variable model incorporating spectral/cepstral analyses and self-reported questionnaires was able to effectively track voice changes after endolaryngeal phonomicrosurgery. Conclusion We verified that most of the variables and the five-variable model were useful for measuring voice recovery in patients with vocal polyps after endolaryngeal phonomicrosurgery.

Objectives Snoring is an important clinical feature of obstructive sleep apnea (OSA), and recent studies suggest that the acoustic quality of snoring sounds is markedly different in drug-induced sleep compared with natural sleep. However, considering differences in sound recording methods and analysis parameters, further studies are required. This study explored whether acoustic analysis of drug-induced sleep is useful as a screening test that reflects the characteristics of natural sleep in snoring patients. Subjects and materials The snoring sounds of 30 male subjects (mean age = 41.8 years) were recorded using a smartphone during natural and induced sleep, with the site of vibration noted during drug-induced sleep endoscopy (DISE); then, we compared the sound intensity (dB), formant frequencies, and spectrograms of snoring sounds. Results Regarding the intensity of snoring sounds, there were minor differences within the retrolingual level obstruction group, but there was no significant difference between natural and induced sleep at either obstruction site. There was no significant difference in the F1 and F2 formant frequencies of snoring sounds between natural sleep and induced sleep at either obstruction site. Compared with natural sleep, induced sleep was slightly more irregular, with a stronger intensity on the spectrogram, but the spectrograms showed the same pattern at both obstruction sites. Conclusion Although further studies are required, the spectrograms and formant frequencies of the snoring sounds of induced sleep did not differ significantly from those of natural sleep, and may be used as a screening test that reflects the characteristics of natural sleep according to the obstruction site.

Objective Currently, various tools have been introduced for the assessment of vocal fold vibration: laryngeal videolaryngoscopy (LV), videokymography (VKG), high speed videoendoscopy (HSV), digital videokymography (DKG), and 2D scanning videokymography (2D VKG). Among these, the authors have recently designed a dual modality examination system using LV and 2D VKG for more detailed information regarding the vibrations of the vocal folds. The clinical availability of this hybrid system offers medical imaging departments a range of potential advantages in the evaluation of vocal fold vibration. The obvious benefit of simultaneous acquisition is the improved integration of information that allows not only optimal anatomic localization, but also physical movement patterns. Other advantages include the lessened inconvenience to patients due to no longer requiring repeated examinations and shortening the examination time, and increased profitability. The purpose of study was to identify the efficacy of real-time dual examination of two different modalities for the evaluation of vocal fold vibration in human subjects and vocal fold vibration simulator. Methods One vocally healthy subject and three patients with vocal fold nodules, a vocal cyst, and vocal fold paralysis took part in this study. The vibratory patterns of the vocal folds were visualized using simultaneous real-time examination of two different modalities. Additionally, qualitative and quantitative analyses of the dual LV and 2D VKG images were performed. Results Real-time dual examination using a two modality system provided high definition images of the vibratory movements of the vocal folds. By assessing the obtained images, we confirmed that the dual modality examination method was useful in the evaluation of pathologic vibratory patterns, even in non-periodic phonation. Conclusion The present system might improve the understanding of the processes of vocal fold vibration and make a contribution to pathologic voice research, as well as clinical practice.

Summary Objective The purpose of present study was to validate a Korean version of the Voice Catastrophization Index for assessing catastrophization in patients with voice problems in a Korean population. Methods Case group patients with voice problems (n = 80) and control group patients without voice problems (n = 25) participated in the study. They were asked to complete three questionnaires: Korean Voice Handicap Index, Korean Voice-Related Quality of Life, and Korean Voice Catastrophization Index (K-VCI). Some of case group with voice problems completed the same three questionnaires again to assess test-retest reliability. Clinicians implemented the Consensus Auditory-Perceptual Evaluation of Voice evaluation to rate the overall severity on voice quality. Results K-VCI scores for case group were significantly higher than those for control group. K-VCI scores were significantly correlated with Korean Voice Handicap Index, Korean Voice-Related Quality of Life, and overall severity. The K-VCI had significant test-retest reliability and its internal consistency was good to excellent (range of Cronbach alpha correlation coefficients: 0.789–0.930). The K-VCI was not affected by patient sex, age, symptom duration, or diagnosis types. K-VCI scores were highest among patients with primary muscle tension dysphonia. Conclusion We validated the K-VCI questionnaire for use in measuring the degree of catastrophization of voice problems in a Korean population. Future studies with a larger sample size will be necessary to further verify this and determine the clinical usefulness of the K-VCI.

Background/Aims: The aims of study were (1) to determine the cut-off values of parameters related to auditory perceptual assessment (visual analog scale [VAS]) and acoustic analysis (cepstral peak prominence [CPP], low-frequency/high-frequency [L/H] ratio, CPP SD, L/H ratio SD, acoustic voice quality index [AVQI], and cepstral spectral index of dysphonia [CSID]) for predicting voice problems within a Korean population, and (2) to verify the discriminative power of these cut-off values. Methods: 1,113 voice samples were analyzed in this study. Perceptual assessments (VAS) were performed by 5 speech-language pathologists. For the acoustic analysis, cepstral parameters, CSID, and AVQI were calculated. The cut-off values of parameters predicting voice problems were obtained using receiver operating characteristic (ROC) analysis. Additionally, the sensitivity, specificity, and area under the ROC curve (AUC) were measured. Results: High reliabilities were observed for the perceptual assessments. The cut-off values of parameters had a high sensitivity, specificity, and AUC. Of these, CSID was the parameter with the highest AUC values. Conclusion: Each parameter demonstrated a high discriminative power for classifying the presence or absence of voice problems. The results of this study could be used as an objective criterion for screening voice problems.

Summary Objectives The acoustic voice quality index (AVQI) is a specific acoustic indicator designed to objectively estimate dysphonia severity and measure the values of acoustic parameters based on the diagnostic category. This study compared the performance of two AVQI versions (2.02 and 3.01, v2 and v3) and PraatCPPS using a voice sample of Korean population. Materials and Methods Voice samples for sustained vowel and connected speech were elicited from 2257 patients across 14 diagnostic categories. Auditory-perceptual (A-P) assessments of dysphonia severity were compared to acoustic parameters of severity derived from two versions of the AVQI (v2 and v3) as well as the PraatCPPS. Results The AVQI-estimated severity (v2 and v3) and PraatCPPS severity for concatenated voice samples strongly correlated with each other and were significantly associated with A-P ratings. The AVQI (v2 and v3) and PraatCPPS showed high reliability in differentiating between pathological voice disorders. Conclusion The AVQI (v2 and v3) and PraatCPPS were strongly correlated with the A-P ratings and provided valid estimates of dysphonia severity. However, the associations of the A-P ratings with the AVQIv2 were significantly stronger than those with the AVQIv3 and PraatCPPS, suggesting that the V2 outperformed the V3 and PraatCPPS.

Purpose: The aims of this study were to: (1) determine the visual analogue scale (VAS) and cepstrum peak prominence (CPP) cut-off points on the ratings of numerical scale (NS) related to the severi...

The purpose of this study was to develop sodium reduced foods for 10 representative high sodium foods often served in the food service industry, and to conduct sensory evaluation on the foods. The foods are kimchi, cucumber salad, banquet noodle, seaweed soup, ahuk soup, pork kimchi stew, red pepper paste pork chops, beef bulgogi, grilled mackerel and saury stew selected based on data from the 2010 national health and nutrition examination survey. The sodium contents of chinese cabbage kimchi were 688.1 mg in the control, 587.3 mg in the 15% reduced sodium sample group (level 1), and 486.5 mg in the 30% reduced sodium sample group (level 2). The corresponding sodium contents of cucumber salad were 406.4 mg, 345.5 mg, and 284.6 mg. The sodium contents of banquet noodle were 1080.2 mg, 912.2 mg, and 765.8 mg, respectively. The sodium contents of seaweed soup were 459.4 mg, 392.1 mg, and 333.0 mg, respectively. The sodium contents of ahuk soup were 615.3 mg, 534.9 mg, and 434.4 mg respectively. The sodium contents of pork kimchi stew were 1156.2 mg, 988.3 mg, and 820.2 mg respectively. The sodium contents of grilled mackerel were 624.6 mg, 557.4 mg, and 456.9 mg respectively. The sodium contents of red pepper paste pork chops were 723.7 mg, 615.0 mg, and 505.3 mg, respectively. The sodium contents of beef bulgogi were 678.3 mg, 561.9 mg, and 473.3 mg, respectively. The sodium contents of saury stew were 676.0 mg, 574.6 mg, and 470.9 mg respectively. Sensory evaluation was conducted with a total of 30 samples consisting of 10 control food groups, 15%, and 30% reduced sodium food groups. Results showed sodium reduction up to level 1 or 2 in chinese cabbage kimchi, cucumber salad, pork kimchi stew, red pepper paste pork chops, beef bulgogi, grilled mackerel and saury stew. However, the soups and noodles showed significant differences between the control and the 15% reduced sodium (level 1) food groups, specifically in banquet noodle, seaweed soup, ahuk soup.

In the present study, we investigated ability of recognition of auditory perception with regards to the quality of voice in postlingual CI adults and proposed a training program to improve within subject reliability. A prospective case-control study was conducted in adults with 7 postlingual deaf who received a CI surgery and 10 normal hearing controls. The pre and post test and training program included parameters of consensus auditory-perceptual evaluation of voice(CAPE-V) with pathological voice sample by using Alvin. In results of pre-post test for monitoring improvements of internal reliability for listeners via the training program, there was statistically significant difference in both test and group. There was statistically significant difference in internal reliability between pre-post test in the normal hearing group, the result was no significant in the CI group. The present study found that CI adults showed less ability in awareness of voice quality compared to normal hearing group. Also the training program improved pitch and loudness in CI adults.

The objective of the study was to determine the effect of the maxillary sinus on the voice. The prospective study was conducted at an academic secondary referral center. A prospective chart review of 43 patients (17 males, 26 females) who conducted a voice recording and survey before and 3 months after middle meatal antrostomy whose lesion was confined to the maxillary sinus. Subjective voice changes were surveyed using a questionnaire. After phonation [∧m ma: the Korean pronunciation of ‘mother’], [Nu Na: the Korean pronunciation of ‘sister’], we analyzed the nasal consonant [m] of [∧m ma] and nasalized vowel [a] of [∧m ma] and [a] of [Nu Na]. In the poll conducted, the change rates for males and females were 41.1 % (7/17) and 15.4 % (4/26), respectively; of the male patients, 85.7 % (6/7) felt that the sound quality was better and 14.3 % (1/6) that it was worse. However, all the female patients felt it was better. Among of the patients with an improved voice, reduced nasal sound was the most frequent observation. In an objective analysis, a tendency to lowered frequencies was observed for nasalized vowels after surgery. Significant differences were observed at second formant frequencies of [a] of [∧m ma] and first formant frequencies of [a] of [Nu Na] in female subjects (P

The purpose of this study was to explore the concurrent validity of the Acoustic Voice Quality Index (AVQI) in a Korean population. We investigated the feasibility of its cutoff values and diagnostic accuracy in discriminating between normal and dysphonic voices.A total of 1,524 native Korean subjects with normal voices (n = 113) and with voice disorders (n = 1,411) were asked to speak and sustain the vowel "a" and to read the Korean text "Walk" aloud. A 2-second mid-speech portion of the sustained vowel sound and two sentences (with 26 syllables) were edited and concatenated, and the AVQI was calculated. Additionally, two auditory-perceptual assessments, namely the Grade, Roughness, Breathiness, Asthenia, Strain scale, and the Consensus Auditory-Perceptual Evaluation of Voice were used by five speech language pathologists to rate the severity of dysphonia.Both auditory-perceptual assessments showed high confidence levels among the five speech language pathologists. The AVQI correlated with grade (G) and overall severity (OS). There were statistically significant differences in AVQI, G, and OS between normal and pathological speech groups. In the receiver operating characteristic curve analysis, AVQI, G, and OS cutoff values were3.33,0.00, and22.00, respectively. The receiver operating characteristic curve analysis indicated that AVQI had excellent diagnostic accuracy for discriminating between normal and dysphonic voices (area under the curve: 0.970-0.977).We demonstrated the concurrent validity of AVQI as a promising tool for assessing overall voice quality and quantifying dysphonia in a Korean-speaking population.

Objectives : The research was performed to be used as basic data for dental hygienists` job satisfaction during clinical practice, and planning and operating effective clinical practice by analyzing stress factors in dental hygienists and the extent of stress caused by students in clinical practice. Methods : The research was aimed at dental hygienists working at college dental hospitals, dental clinic of general hospitals, dental hospitals and dental clinics located in Seoul and Gyeonggi province where clinical practices were conducted for dental hygiene students. For analysis, collected data was analyzed by using SPSS 20.0. Results : Results derived from analysis on characteristic difference by pattern of hospital were observed that there was a significant difference in job satisfaction by pattern of hospital. Results from analysis on correlation among stress factors were observed that there was correlation between behavior and attitude, interpersonal relationships, role and activity, ideal and value, and treatment fields. Results derived from analysis on the effect of stress factors on the job satisfaction were observed that role and activity (p

Snoring is a sign of increased upper airway resistance and is the most common symptom suggestive of obstructive sleep apnea. Acoustic analysis of snoring sounds is a non-invasive diagnostic technique and may provide a screening test that can determine the location of obstruction sites. We recorded snoring sounds according to obstruction level, measured by DISE, using a smartphone and focused on the analysis of formant frequencies. The study group comprised 32 male patients (mean age 42.9 years). The spectrogram pattern, intensity (dB), fundamental frequencies (F 0), and formant frequencies (F 1, F 2, and F 3) of the snoring sounds were analyzed for each subject. On spectrographic analysis, retropalatal level obstruction tended to produce sharp and regular peaks, while retrolingual level obstruction tended to show peaks with a gradual onset and decay. On formant frequency analysis, F 1 (retropalatal level vs. retrolingual level: 488.1 ± 125.8 vs. 634.7 ± 196.6 Hz) and F 2 (retropalatal level vs. retrolingual level: 1267.3 ± 306.6 vs. 1723.7 ± 550.0 Hz) of retrolingual level obstructions showed significantly higher values than retropalatal level obstruction (p

The purpose of this study was to examine the awareness of dental hygiene students on the components of the dental hygiene curriculum. The subjects in this study were 934 dental hygiene students, on whom a survey was conducted in April and Jun, 2009. The collected data were analyzed by the statistical package PASW 18.0. The findings of the study were as follows: The students from the midsection of the nation put the highest value on educational objectives, selection of what to teach and evaluation, and the students from the metropolitan area set the lowest value on those components. The students who took junior college courses took a better view of those components than those who took college courses. In terms of the organization of what to teach, the students from the midsection of the nation rated it highest, and the students from the Honam area rated it lowest. And those who took college courses took a little better view of it than the students who took junior college courses. Among the components of the curriculum, the educational objective factor was rated higher in terms of vocational education, morality and ethics, and that was rated lower in terms of creativity. The selection of what to teach was rated higher in terms of learning possibility and was rated lower in terms of content validity and relevance. The organization of what to teach was rated highest in terms of continuity, followed by sequence and integration. The educational evaluation factor was rated higher in the area of school evaluation and was rated lowest in the area of national examinations.

Hot and spicy flavor grading in hot pepper powder for gochujang in various cultivars was studied using sensory and physicochemical characteristics. Chungyang, which had the highest capsaicin content had very low redness a value of 17.49 representing stronger red color does not relate to the stronger hot and spicy flavor. Sen sory results showed that chungyang had significantly the highest value of hot and spicy aroma and flavor of 5.73 and 7.87, respectively(p

In-Sn-Zn-O (ITZO) films and a TiO 2 buffer layer were deposited on PET substrates at room temperature by magnetron co-sputtering using two cathodes (DC, RF) and RF reactive sputtering at an O 2 flow ratio of 2%, respectively. After applying a TiO 2 buffer layer, the ITZO/TiO 2 films showed an amorphous structure with a resistivity that decreased with increasing TiO 2 buffer layer thickness. The mechanical properties were highest at a TiO 2 thickness of 5 nm, which was confirmed by the bending test and optical microscopy images of the cracks. The resistivity and transmittance of the ITZO film with a 5 nm thick TiO 2 buffer were 6.55 × 10 − 4 Ωcm and > 75% at 550 nm, respectively.

A pure tone audiometer should be able to produce both pure tone and masking noise with exact sound pressure level and frequency. For such purpose, it is unavoidable to periodically calibrates pure tone audiometer. However, manual acoustic calibration requires not only attention but also long time. It is possible to execute automatically calibration using software if it is PC-based pure tone audiometer. In this paper, we describe auto-calibration software for PC-based pure tone audiometer and dedicated sound level meter which has been implemented upon PC by us. To verify auto-calibration module, we examine whether output of PC-based audiometer calibrated through auto-calibration of this paper satisfies RETSPL of IEC or not.

Ce-doped indium tin oxide (ITO:Ce) films were deposited on flexible polyimide substrates by DC magnetron sputtering using ITO targets containing various CeO2 contents (CeO2 : 0, 0.5, 3.0, 4.0, 6.0 wt.%) at room temperature and post-annealed at 200 °C. The crystallinity of the ITO films decreased with increasing Ce content, and it led to a decrease in surface roughness. In addition, a relatively small change in resistance in dynamic stress mode was obtained for ITO:Ce films even after the annealing at high temperature (200 °C). The minimum resistivity of the amorphous ITO:Ce films was 3.96 × 10− 4 Ωcm, which was deposited using a 3.0 wt.% CeO2 doped ITO target. The amorphous ITO:Ce films not only have comparable electrical properties to the polycrystalline films but also have a crystallization temperature > 200 °C. In addition, the amorphous ITO:Ce film showed stable mechanical properties in the bended state.

In this study, the amount of decrease in coercive field of congruent lithium niobate during repeated poling and back-poling was measured. The polarization is reversed in 300 ms and then back-poled during the rest period. The coercive field can be decreased around 1 kV/mm with a repeated poling interval of 5 s. As the interval prolonged, the poling field decrease became smaller, and a stretched exponential function is suggested for the experimental fitting resulting in a set of meaningful parameters. These values are essential for the design of high quality domain engineering.

Although a redox shift can regulate the development of cells, including proliferation, differentiation, and survival, the role of the glutathione (GSH) redox status in macrophage differentiation remains unclear. In order to elucidate the role of a redox shift, macrophage-like cells were differentiated from the bone marrow-derived monocytes that were treated with a macrophage colony stimulating factor (M-CSF or CSF-1) for 3 days. The macrophagic cells were characterized by a time-dependent increase in three major symptoms: the number of phagocytic cells, the number of adherent cells, and the mRNA expression of c-fms, a M-CSF receptor that is one of the macrophage-specific markers and mediates development signals. Upon M-CSF-driven macrophage differentiation, the GSH/GSSG ratio was significantly lower on day 1 than that observed on day 0 but was constant on days 1-3. To assess the effect of the GSH-depleted and -repleted status on the differentiation and phagocytosis of the macrophages, GSH depletion by BSO, a specific inhibitor of the de novo GSH synthesis, inhibited the formation of the adherent macrophagic cells by the down-regulation of c-fms, but did not affect the phagocytic activity of the macrophages. To the contrary, GSH repletion by the addition of NAC, which is a GSH precursor, or reduced GSH in media had no effect on macrophage differentiation, and led to a decrease in the phagocytic activity. Furthermore, we observed that there is checkpoint that is capable of releasing from the inhibition of the formation of the adherent macrophagic cells according to GSH depletion by BSO. Summarizing, these results indicate that the intracellular GSH status plays an important role in the differentiation and phagocytosis of macrophages.