Open Quotient Research Articles

Preliminary Findings of Vocal Fold Vibratory Characteristics of Singers Analyzed by Laryngeal High-Speed Videoendoscopy

ObjectivesThis study investigates the vocal fold vibratory dynamics of singers, which are postulated to differ from those of normal speakers due to the singers' regular vocal training. The measurement of vocal fold vibration involved the utilization of laryngeal high-speed video endoscopy (LHSV) and subsequent LHSV-based analysis. The focus is to characterize and compare the LHSV-based measures derived from the glottal area waveform (GAW), namely fundamental frequency (F0GAW), glottal perturbation (jitterGAW and shimmerGAW), open quotient (OQGAW), and Nyquist plots, between singers and normal speakers across genders. MethodsParticipants comprised 13 singers from a local cultural and heritage academy and 56 normal speakers from a local university, all were evaluated to have normal voices. Each participant underwent LHSV procedures to capture images of vocal fold vibration, which were subsequently analyzed to generate the LHSV-based measures. ResultsMale singers exhibited lower F0GAW, jitterGAW, shimmerGAW, and OQGAW than female singers. When compared to normal speakers, male singers demonstrated higher F0GAW, and lower jitterGAW and shimmerGAW. No difference in OQGAW was found between male singers and normal speakers. Female singers exhibited lower jitterGAW compared to normal speakers, but no differences were observed in shimmerGAW and OQGAW. The results of Nyquist plots indicated no gender-related associations between types of rim width and among singers. However, for rim pattern, male singers were associated with a higher percentage of clustered rim, suggesting more regular vocal fold vibration, compared to female singers and male normal speakers. ConclusionsSingers, particularly male singers, demonstrate distinct and potentially superior vocal fold vibrations compared to normal speakers, likely attributed to their regular vocal training, resulting in refined vocal fold configurations even during speaking. Despite the limited sample of singers, the study offers valuable insights into the vocal fold vibratory behaviors in singers analyzed using LHSV.

Effects of Speech Characteristics on Electroglottographic and Instrumental Acoustic Voice Analysis Metrics in Women With Structural Dysphonia Before and After Treatment.

Literature suggests a dependency of the acoustic metrics, smoothed cepstral peak prominence (CPPS) and harmonics-to-noise ratio (HNR), on human voice loudness and fundamental frequency (F0). Even though this has been explained with different oscillatory patterns of the vocal folds, so far, it has not been specifically investigated. In the present work, the influence of three elicitation levels, calibrated sound pressure level (SPL), F0 and vowel on the electroglottographic (EGG) and time-differentiated EGG (dEGG) metrics hybrid open quotient (OQ), dEGG OQ and peak dEGG, as well as on the acoustic metrics CPPS and HNR, was examined, and their suitability for voice assessment was evaluated. In a retrospective study, 29 women with a mean age of 25 years (± 8.9, range: 18-53) diagnosed with structural vocal fold pathologies were examined before and after voice therapy or phonosurgery. Both acoustic and EGG signals were recorded simultaneously during the phonation of the sustained vowels /ɑ/, /i/, and /u/ at three elicited levels of loudness (soft/comfortable/loud) and unconstrained F0 conditions. A linear mixed-model analysis showed a significant effect of elicitation effort levels on peak dEGG, HNR, and CPPS (all p < .01). Calibrated SPL significantly influenced HNR and CPPS (both p < .01). Furthermore, F0 had a significant effect on peak dEGG and CPPS (p < .0001). All metrics showed significant changes with regard to vowel (all p < .05). However, the treatment had no effect on the examined metrics, regardless of the treatment type (surgery vs. voice therapy). The value of the investigated metrics for voice assessment purposes when sampled without sufficient control of SPL and F0 is limited, in that they are significantly influenced by the phonatory context, be it speech or elicited sustained vowels. Future studies should explore the diagnostic value of new data collation approaches such as voice mapping, which take SPL and F0 effects into account.

Does forced whisper have an impact on voice parameters?

ObjectivesThere has been the assumption that whispering may impact vocal function, leading to the widespread recommendation against its practice after phonosurgery. However, the extent to which whispering affects vocal function and vocal fold oscillation patterns remains unclear.Methods10 vocally healthy subjects (5 male, 5 female) were instructed to forcefully whisper a standardized text for 10 min at a sound level of 70 dB(A), measured at a microphone distance of 30 cm to the mouth. Prior to and following the whisper loading, the dysphonia severity index was assessed. Simultaneously, recordings of high speed videolaryngoscopy (HSV), electroglottography, and audio signals during sustained phonation on the vowel /i/ (250 Hz for females and 125 Hz for males) were analyzed after segmentation of the HSV material.ResultsThe pre-post analysis revealed only minor changes after the intervention. These changes included a rise in minimum intensity, an increase in the glottal area waveform-derived open quotient, and the glottal gap index. However, no statistically significant changes were observed in the harmonic-to-noise-ratio, the glottal- to-noise-excitation-ratio, and the electroglottographic open quotient.ConclusionOverall, the study suggests that there are only small effects on vocal function in consequence of a forced whisper loading.

A Study on Vocal Attack During Voice Therapy Exercises Using Photoglottography

ObjectiveThere are various exercises for voice therapy, but current evidence is insufficient to decide the most effective training technique for each type of dysphonia. This study focused on vocal attack as one of the causes of dysphonia. Hence, vocal attack during voice therapy exercises was investigated using photoglottogram (PGG). MethodsEighteen healthy adult subjects (10 males and 8 females) were included in this study. The first to fifth vocal waves during natural voice, hard and soft voice onset, and semi-occluded vocal tract exercises (SOVTE: humming, tubing, and lip trill) were assessed. We also calculated the 25% vocal fold open quotient (OQ) using a PGG and compared these parameters. ResultsThe 25% OQ did not show any sex-related differences. In the first wave, the 25% OQ for hard attack was significantly lower than that for soft attack, tongue out humming, and lip trill. In contrast, the 25% OQ value for soft attack was significantly higher than that for humming, 6 mm tube phonation, and lip trill. The 25% OQ values differed between SOVTE procedures; it was higher for the 13 mm tube phonation than for the 6 mm tube phonation. The 25% OQ at voice onset in the first to fifth waves differed depending on the SOVTE technique, indicating different voice onset patterns. ConclusionsThese results suggest that appropriate selection of SOVTE tailored for each patient may have benefit in further voice improvement. Future research should focus on conducting a similar study on patients with dysphonia.

Glottal Features in Vocal Assessment Following Thyroidectomy

ObjectivesVocal dysfunction is a frequent complication following thyroidectomy that can be associated with a negative impact on patient’ quality of life. Although the effect of thyroidectomy on acoustic features has been widely used, the examination of glottal flow characteristics to assess vocal outcomes following thyroid gland surgery has not been included in empirical research, to date. The goal of our study was to evaluate early and short-term vocal outcomes following thyroidectomy based on the analysis of glottal acoustic features during speech production. Study designProspective analytical study Materials and methodsWe evaluated vocal outcomes in patients who underwent thyroidectomy between September 2021 and March 2022. We extracted glottal flow features from their vocal recordings preceding surgery and post-operatively at Day1 and Month1 post-operatively. The extraction of glottal features was performed using a signal processing based approach. We extracted the following features: Open quotients (OQ1 and OQ2), Quasi-open quotient (QoQ), Closing quotient (ClQ), Amplitude quotient (AQ), Normalized Amplitude quotient (NAQ) and Speed quotients (SQ1 and SQ2).We included 39 patients. OQ2 and QoQ decreased significantly at Day1 and Month1. OQ1 and NAQ decreased significantly at Month1. ClQ remained stable at both post-operative assessments. AQ decrease was not significant at both dates. SQ1 increased at Day1 and Month1 but the change was not significant. SQ2 decreased significantly at both Day1 and Month1. OQ, QoQ AQ, NAQ and SQ2 did not recover at Month1. We noted that the decrease of SQ1 and SQ2 correlated significantly with the increase of the Voice Handicap Index-10 (VHI-10) at Month1. ConclusionGlottal acoustic features can be a reliable modality to detect vocal changes following thyroidectomy. Thyroidectomy was associated with a vocal dysfunction that was manifested by the decrease of open, amplitude, and speed quotients. Glottal features can present a potential tool to objectively assess the effect of thyroidectomy on vocal folds movements.

무후두 음성에 대한 성문 역 여과 분석의 유용성

The purpose of this study was to present basic data for voice rehabilitation by acoustically analyzing the voices of subjects who lost their voice due to laryngeal excision and used esophageal vocalization as an alternative method. We aimed to investigate the usefulness of esophageal speech analysis using open source software that can automatically run glottic inverse filtration (GIF) analysis and analyze various parameter values. GIF analysis was performed on 20 normal adults and 20 people with negative esophageal vocalization. Analysis variables included open quotient, speed quotient, closure quotient, amplitude quotient, normalized amplitude quotient, and semi-open quotient. As a result of glottal inverse filtration analysis of normal voice and esophageal vocalization, the values of esophageal vocalization were lower in all variables compared to normal vocalization, and the average score of esophageal vocalization was found to be 1/4 of that of normal vocalization. In this study, objective values for the glottal waveform of normal adults were obtained, and these parameter values were applied to esophageal voice to determine the extent to which they differ from normal voice, and the GIF value was used to determine the degree of voice progress in esophageal voice rehabilitation. It is believed that it can be used for prediction.

From λ-hollow frames to λ-repletions in W: I. The scaffolding of a completely regular frame

We hollow out a given completely regular frame L by removing, for an uncountable regular cardinal number κ, the dense κ-cozero elements of L. This we do by passing to the cointersection of the proper dense open κ-cozero quotients of L. The quotient frame is κ-hollow, i.e., it has no proper dense κ-cozero elements, and this passage is a bireflection in the category of frames with skeletal morphisms. Thus each frame L has a descending sequence of dense quotient frames of increasing hollowness, indexed by the uncountable regular cardinal numbers, culminating in the classical minimal dense quotient of L.Our purpose is to shed light on the structure of a given frame L by examining the collection of quotients and sub-κ-frames which arise in its hollowing sequence, to which we refer collectively as the scaffolding of L.

An electroglottographic study on the effect of following context on glottal constriction in Australian English coda /t/

To achieve inhibition of voicing for voiceless speech sounds, the glottis may be either spread or constricted. Glottal spreading may lead to breathiness, and constriction to glottalization. Previous research has shown that glottalization associated with English coda /t/ differs as a function of surrounding environment, with glottalization more likely when the following word begins with a sonorant consonant (such as /l, n/) compared to other environments. However, it is unclear the extent to which following sonorant consonants induce glottalization compared to following vowels. We used an electroglottograph to record 12 Australian English speakers producing phrases eliciting coda /t/ in target words preceding words with onset sonorants /n, l/ (now, long) and onset vowels /əʉ, ə/ (only, again). Open quotient (OQ) was established through the second half of the target word vowel. Increasing OQ indicates breathiness whereas lowering OQ indicates constriction. Using generalized additive mixed modelling we found that the OQ of vowels preceding coda /t/ in the sonorant-following context was significantly lower than in vowel-following contexts. This indicates greater glottal constriction when a sonorant consonant follows the coda /t/, showing that coda /t/ voicelessness is implemented differently before sonorant consonants compared to vowels

Vocal Vibration Opening Onset Position Abnormality in Patients With Adductor Spasmodic Dystonia by Using High-Speed Endoscopy

To analyze vocal fold vibration onset in patients with adductor laryngeal dystonia (ADLD) by analyzing vocal vibration opening onset position (VVOOP). Case-control study SETTING: A voice center. Eleven patients with ADLD diagnosed in our voice center were enrolled in the ADLD group. Eleven healthy subjects matched by exact age and gender to the ADLD patients were selected as the control group. All subjects underwent laryngeal high-speed video endoscopy. VVOOP and its change were assessed by two otolaryngologists. The multiline video kymography was used to analyze the openquotient (OQ) and standard deviation of OQ. VVOOP had more than one position in 54.6% (6/11) of the patients with ADLD, which was higher than the control group (P<0.05). VVOOP appeared in the front of the vocal fold in 54.6% (6/11) of patients with ADLD and in the back of the vocal fold in 81.8% (9/11) of patients with ADLD. VVOOP can be abnormal in 90.9% (10/11) of patients with ADLD, and the rate of VVOOP abnormality was higher than that of the control group (P<0.05). Of 11, 6 (54.6%) patients with ADLD had a variable VVOOP; thevariability rate of VVOOP was higher than that in the control group(P<0.05). OQ and OQ standard deviation in the ADLD group were significantly greater than in the control group (P<0.05). In patients with ADLD, vocal fold vibration was irregular, and VVOOP was abnormal and had a variable position and could reflect variability of the vocal vibration. Level 4.

Using a vertical three-mass computational model of the vocal folds to match human phonation of three adult males.

Computer models of phonation are used to study various parameters that are difficult to control, measure, and observe in human subjects. Imitating human phonation by varying the prephonatory conditions of computer models offers insight into the variations that occur across human phonatory production. In the present study, a vertical three-mass computer model of phonation [Perrine, Scherer, Fulcher, and Zhai (2020). J. Acoust. Soc. Am. 147, 1727-1737], driven by empirical pressures from a physical model of the vocal folds (model M5), with a vocal tract following the design of Ishizaka and Flanagan [(1972). Bell Sys. Tech. J. 51, 1233-1268] was used to match prolonged vowels produced by three male subjects using various pitch and loudness levels. The prephonatory conditions of tissue mass and tension, subglottal pressure, glottal diameter and angle, posterior glottal gap, false vocal fold gap, and vocal tract cross-sectional areas were varied in the model to match the model output with the fundamental frequency, alternating current airflow, direct current airflow, skewing quotient, open quotient, maximum flow negative derivative, and the first three formant frequencies from the human production. Parameters were matched between the model and human subjects with an average overall percent mismatch of 4.40% (standard deviation = 6.75%), suggesting a reasonable ability of the simple low dimensional model to mimic these variables.

Presenting Quotient Locales

It is often useful to be able to deal with locales in terms of presentations of their underlying frames, or equivalently, the geometric theories which they classify. Given a presentation for a locale, presentations for its sublocales can be obtained by simply appending additional relations, but the case of quotient locales is more subtle. We provide simple procedures for obtaining presentations of open quotients, proper quotients or general triquotients from presentations of the parent locale. The results are proved with the help of the suplattice, preframe and dcpo coverage theorems and applied to obtain presentations of the circle from ones for mathbb {R} and [0, 1].

Auditory Perception of Impulsiveness and Tonality in Vocal Fry

Vocal fry is a voice quality that occurs in a healthy voice, but it can also be a sign of a voice disorder. In this study, we investigated the relationship between the parameters of voice production, a dedicated psychoacoustic feature, and the perceptual aspects of vocal fry. Two perceptual experiments were carried out to determine whether the fundamental frequency, the open quotient, and the glottal area pulse skewness affect the perception of vocal fry in synthetic vowels. Thirteen listeners participated in the perceptual experiments to assess the following attributes: binary fry (yes/no) and impulsiveness, tonality, and naturalness (7-point Likert scales). The results suggest that the perception of vocal fry is mainly triggered by a low fundamental frequency, but the open quotient also plays a role, with narrower glottal area pulses slightly increasing the probability of perceived fry. Perceived tonality is inversely related to perceived impulsiveness. Internal reference standards of listeners appear to have fixed elements but may also be affected by anchoring and the short-term (i.e., within-vowel) context of the stimuli. In addition, the prominence of the peaks observed in the loudness curve over time appears to be related to graduations of fry.

Various measures and the distinction of tense and lax contrasts: The case of Zhoucheng Bai

The acoustic characteristics of the tense and lax contrasts have been studied extensively, and different measures were attested to be related, but few of these studies discussed different measures together and explored their relationships. Three of the eight tones in Zhoucheng Bai (i.e., T2, T6, and T7) are marked as tense tones, while the rest are lax tones. Based on Electroglottographic (EGG) and acoustic signals, this paper examined eight measures, namely fundamental frequency (F0), open quotient (OQ), speed quotient (SQ), H1*-H2*, H2*-H4*, H1*-A1*, H1*-A2*, and H1*-A3*, in the data obtained from 10 Zhoucheng Bai speakers. It shows that different measures perform variously in the distinction of tense and lax contrasts. F0 well distinguishes between T6 and T1, and both EGG measures and spectral measures can differentiate between T2 and T8, but none of measures reflects the contrast of T7 and T3 for all speakers. The case of T7 and T3 suggests that the relationship between production and perception is not as straightforward as commonly assumed and needs further research. Although different measures don't always participate in the distinction of tense and lax contrasts together and have equal contributions, they are significantly correlated with each other, which are supported by the correlation analysis.

Effect of nodule size and stiffness on phonation threshold and collision pressures in a synthetic hemilaryngeal vocal fold model.

Synthetic vocal fold (VF) replicas were used to explore the role of nodule size and stiffness on kinematic, aerodynamic, and acoustic measures of voiced speech production. Emphasis was placed on determining how changes in collision pressure may contribute to the development of phonotrauma. This was performed by adding spherical beads with different sizes and moduli of elasticity at the middle of the medial surface of synthetic silicone VF models, representing nodules of varying size and stiffness. The VF models were incorporated into a hemilaryngeal flow facility. For each case, self-sustained oscillations were investigated at the phonation threshold pressure. It was found that increasing the nodule diameter increased the open quotient, phonation threshold pressure, and phonation threshold flow rate. However, these values did not change considerably as a function of the modulus of elasticity of the nodule. Nevertheless, the ratio of collision pressure to subglottal pressure increased significantly for both increasing nodule size and stiffness. This suggests that over time, both growth in size and fibrosis of nodules will lead to an increasing cycle of compensatory vocal hyperfunction that accelerates phonotrauma.

A Quantitative Examination of Vocal Fold Vibratory Changes Using Two-Dimensional Scanning Digital Kymography After Angiolytic Laser Stripping for Vocal Fold Leukoplakia

Background and Objectives Vocal fold leukoplakia is characterized as white plaque on the epithelium of the vocal folds and can be treated by angiolytic laser stripping surgery. However, postoperative changes in the vibratory patterns of vocal folds have not been investigated quantitatively. The purpose of this study was to investigate the changes in vocal fold vibration after angiolytic laser surgery in patients with unilateral vocal fold leukoplakia using the twodimensional scanning digital kymography (2D DKG).Subjects and Method Medical records of seven males (age=62.14±12.40 yrs) with unilateral vocal fold leukoplakia who underwent angiolytic laser stripping were reviewed. Before and after the surgery (post-operative day=82.57±28.55 days), a multi-dimensional voice assessment was performed along with a 2D DKG study. For 2D DKG images, the amplitude symmetry index (ASI), phase symmetry index (PSI), and open quotient (OQ) were calculated using the ImageJ program. In addition, pre- versus postoperative data were compared, and the correlation between the changes in 2D DKG parameters and voice outcomes was explored.Results Results indicated that the absolute ASI (&lt;i&gt;p&lt;/i&gt;=0.028) and OQ (&lt;i&gt;p&lt;/i&gt;=0.028) of the 2D DKG study, grade (&lt;i&gt;p&lt;/i&gt;=0.038) and breathy (&lt;i&gt;p&lt;/i&gt;=0.034) of the GRBAS scale, σPitch measured by the electroglottography (&lt;i&gt;p&lt;/i&gt;=0.043), the physical score of the VHI (&lt;i&gt;p&lt;/i&gt;=0.042), and the total score (&lt;i&gt;p&lt;/i&gt;=0.043) and the tiredness score (&lt;i&gt;p&lt;/i&gt;=0.043) of the VFI decreased after surgery. Decrease in the absolute ASI was correlated with changes in the grade (rho=0.850) and breathy (rho=0.777) scale measures, while decreased OQ were correlated with the changes in the physical score of the VHI (rho=0.901) and tiredness score of the VFI (rho=0.847).Conclusion The improved vocal fold vibratory patterns after angiolytic laser surgery for vocal fold leukoplakia can be evaluated objectively using the 2D DKG study. Angiolytic laser stripping enables the preservation of vocal fold vibration after the surgery and is considered a valuable surgical option for treating vocal fold leukoplakia.

Interactions Between Breathy and Rough Voice Qualities and Their Contributions to Overall Dysphonia Severity.

Dysphonic voices typically present multiple voice quality dimensions. This study investigated potential interactions between perceived breathiness and roughness and their contributions to overall dysphonia severity. Synthetic stimuli based on four talkers were created to systematically map out potential interactions. For each talker, a stimulus matrix composed of 49 stimuli (seven breathiness steps × seven roughness steps) was created by varying aspiration noise and open quotient to manipulate breathiness and superimposing amplitude modulation of varying depths to simulate roughness. One-dimensional matching (1DMA) and magnitude estimation (1DME) tasks were used to measure perceived breathiness, roughness, their potential interactions, and overall dysphonia severity. Additional 1DME tasks were used to assess a set of natural stimuli that varied along both breathiness and roughness. For the synthetic stimuli, the 1DMA task indicated little interaction between the two voice qualities. For the 1DME task, breathiness magnitude was influenced by roughness step to a greater extent than roughness magnitude was influenced by breathiness step. The additive contributions of breathiness and roughness to overall severity gradually diminished with increasing breathiness and roughness steps, possibly reflecting a ceiling effect in the 1DME task. For the natural stimuli, little consistent interaction was observed between breathiness and roughness. The matching task revealed minimal interaction between perceived breathiness and roughness, whereas the magnitude estimation task revealed some interaction between the two qualities and their cumulative contributions to overall dysphonia severity. Task differences are discussed in terms of differences in response bias and the role of perceptual anchors. https://doi.org/10.23641/asha.21313701.

The Non-Coalescence of /h/ and Incomplete Neutralization in South Jeolla Korean.

This study examines articulatory and acoustic data in order to investigate the non-coalescence of /h/ in South Jeolla. Seoul Korean speakers produce /pap/ "rice" followed by /hana/ "one" as [pa.pha.na] with the coalescence of /p/ and /h/; this is called an aspiration merger. In South Jeolla Korean, this merger may be blocked, as in cases where speakers produce /pap+hana/ as [pa.ba.na]. Electroglottographic (EGG) data indicate the existence of two groups of South Jeolla speakers: one that merges the plosive and /h/ (the merger group), and the other with the canonical South Jeolla Korean pronunciation that does not merge the two consonants (the non-merger group). The production of non-coalesced lenis stops in the non-merger group is phonetically comparable with an underlying lenis stop produced by both of the groups. However, in the non-merger group, the open quotient (OQ) of a vowel following a non-coalesced lenis stop is higher (breathier) than that of an underlying lenis stop. Spectral tilt results display a similarly increased breathiness when the vowel follows a non-coalesced lenis stop. As for the non-merger group of South Jeolla, we argue that speakers display incomplete neutralization such that the non-merger group produces two types of voiced lenis stops differing in the phonation of the following vowel. These findings suggest that previous phonological analyses that posit the /h/-deletion in the non-merger group of South Jeolla Korean need to be revisited.

Lombard Effect in Individuals With Nonphonotraumatic Vocal Hyperfunction: Impact on Acoustic, Aerodynamic, and Vocal Fold Vibratory Parameters.

This exploratory study aims to investigate variations in voice production in the presence of background noise (Lombard effect) in individuals with nonphonotraumatic vocal hyperfunction (NPVH) and individuals with typical voices using acoustic, aerodynamic, and vocal fold vibratory measures of phonatory function. Nineteen participants with NPVH and 19 participants with typical voices produced simple vocal tasks in three sequential background conditions: baseline (in quiet), Lombard (in noise), and recovery (5 min after removing the noise). The Lombard condition consisted of speech-shaped noise at 80 dB SPL through audiometric headphones. Acoustic measures from a microphone, glottal aerodynamic parameters estimated from the oral airflow measured with a circumferentially vented pneumotachograph mask, and vocal fold vibratory parameters from high-speed videoendoscopy were analyzed. During the Lombard condition, both groups exhibited a decrease in open quotient and increases in sound pressure level, peak-to-peak glottal airflow, maximum flow declination rate, and subglottal pressure. During the recovery condition, the acoustic and aerodynamic measures of individuals with typical voices returned to those of the baseline condition; however, recovery measures for individuals with NPVH did not return to baseline values. As expected, individuals with NPVH and participants with typical voices exhibited a Lombard effect in the presence of elevated background noise levels. During the recovery condition, individuals with NPVH did not return to their baseline state, pointing to a persistence of the Lombard effect after noise removal. This behavior could be related to disruptions in laryngeal motor control and may play a role in the etiology of NPVH. https://doi.org/10.23641/asha.20415600.

Analysis of vocal fold vibration characteristics of spasmodic dysphonia by laryngeal high speed photography combined with glottis area wave

Objective: To analyze the characteristics of vocal fold vibration of normal people and patients with spasmodic dysphonia (SD) using laryngeal high speed videoendoscopy combined with glottal area wave analysis. Methods: This prospective study examined twenty healthy subjects (10 males and 10 females), 12 patients with adductor spasmodic dysphonia(AdSD) (2 males,10 females)as AdSD group and 2 patients with abductor spasmodic dysphonia(AbSD) (2 males) as AbSD group. Twelve of healthy subjects (2 males,10 females) were selected as control group according to AdSD group gender match. All the subjects were recruited from the Department of Voice, Zhongshan Hospital, Xiamen University from October 2019 to December 2020. All subjects underwent laryngeal high speed videoendoscopy and 10 vibration periods were selected from each recording and were used to quantitatively analyze the change of glottal area and vocal fold vibration parameters (Speed Quotient (SQ), Open Quotient (OQ) and Close Quotient (CQ)). Results: 1. There were statistically significant differences in SQ, CQ and OQ between males and females in the healthy subjects (t=12.28, 5.59, 5.59, P<0.05). The change of the glottal area during each vibration period in healthy subjects was relatively stable(0.19-0.42). 2. The change of the glottal area during each vibration period in AdSD subjects had larger fluctuations, with the glottal area change index fluctuating in the range of 0.31 to 0.62. The SQ value of the AdSD group was significantly lower than that of control group (t=4.246, P<0.05). There were no significant differences in OQ and CQ between AdSD group and normal group (t=1.064, 1.332, P>0.05); The SQ value of the AbSD group tended to increase compared to normal group. Conclusions: Laryngeal high speed videoendoscopy combined with glottal area wave analysis has a certain reference value in the studying the vibration characteristics of SD patients. SQ has good specificity.

Entropy pair realization

AbstractWe show that the complete positive entropy (CPE) class $\alpha $ of Barbieri and García-Ramos contains a one-dimensional subshift for all countable ordinals $\alpha $ , that is, the process of alternating topological and transitive closure on the entropy pairs relation of a subshift can end on an arbitrary ordinal. This is the composition of three constructions. We first realize every ordinal as the length of an abstract ‘close-up’ process on a countable compact space. Next, we realize any abstract process on a compact zero-dimensional metrizable space as the process started from a shift-invariant relation on a subshift, the crucial construction being the implementation of every compact metrizable zero-dimensional space as an open invariant quotient of a subshift. Finally, we realize any shift-invariant relation E on a subshift X as the entropy pair relation of a supershift $Y \supset X$ , and under strong technical assumptions, we can make the CPE process on Y end on the same ordinal as the close-up process of E.