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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

O atleta da voz: o cantor lírico e o seu corpo / The voice athlete: the classical singer and the body

André Azevedo Marques Estevez 15 May 2017 (has links)
É comum observarmos entre os cantores a ideia de que o corpo é o instrumento de sua arte. Apesar de vivermos num momento onde entender a vida e nossas experiências por uma perspectiva sistêmica deveria ser algo já difundido, perpetua-se um modelo de entendimento do canto compartimentalizado e desconectado da vida do cantor. Tentando entender esse problema, nesta pesquisa de natureza qualitativa questionamos se os cantores líricos identificam o seu corpo como seu instrumento, ou como locus da performance. E, nesse sentido, qual é o papel das práticas motoras (práticas corporais e de atividade física) no seu desenvolvimento e na sua performance. Sabendo que essas questões são aspectos importantes das práticas de Educação Somática, propusemos interlocução entre esse tipo de prática corporal e as experiências com cantores líricos. A investigação foi organizada em três etapas: 1) Prática de Educação Somática associada a aulas de canto individuais, por um ano; 2) Prática de Educação Somática associada a aulas de canto em grupo, em dois encontros; 3) Entrevistas semiestruturadas com 3 cantoras e 2 cantores que possuem experiência com Educação Somática. Durante os encontros práticos, foi tomado nota das impressões, percepções e relatos dos estudantes num caderno de campo. O material, constituído das conversas e das experiências práticas, foi analisado por uma perspectiva somaestética, disciplina filosófica proposta por Richard Shusterman. Fica evidenciado que, para os participantes da investigação, a prática de Educação Somática permite que eles sintam e conheçam a si mesmos de maneira ampliada e fica claro como corpo e voz se tornam indissociáveis. Também há a compreensão de que o corpo que atua, o que canta e o que ensina são os mesmos. Apesar de haver uma percepção do corpo subjetivado quando relatam suas experiências, a ideia de corpo como instrumento é aceita pelos participantes dessa investigação / It is common to find among singers the idea that the body is the instrument of their art. Although we live in a time where to understand life and our experiences from a systemic perspective should be something widespread, an understanding of singing as something compartmentalized and disconnected from the singers life is perpetuated. Trying to understand this issue, in this research of qualitative nature we ask if classical singers identify their bodies as their instrument, or as locus of performance. And, in this regard, what is the role of motor practices (bodily practices and physical activity) in their development and their art. Knowing that these issues are important aspects of Somatic Education practices, we intended to make an interlocution between this type of bodily practice and the experience with classical singers. This inquiry was organized in three stages: 1) Somatic Education practices associated with individual singing lessons, through a whole year; 2) Somatic Education practices associated with group singing lessons, in two meetings; 3) Semi-structures interviews with 5 singers who are experienced in Somatic Education. Along the practice meetings, impressions, perceptions and reports were written down as fieldnotes. The data, constituted of conversations and practical experiences, was analyzed through a somaesthetic perspective, a philosophical discipline proposed by Richard Shusterman. It becomes evident that to the participants of this inquiry, the practice of Somatic Education allows them to feel and know themselves in an expanded way and it becomes clear how body and voice become inseparable. There is, also, the understanding that the acting body, the singing body and the teaching body are all the same. Although there is the comprehension of a subjectified body when they report their experience, the idea of body as an instrument is accepted by the participants of this inquiry
402

The Effect of Subglottic Stenosis on the Aerodynamic, Acoustical, and Vibratory Output of Synthetic Vocal Fold Models

Hilton, Benjamin Allen 01 August 2019 (has links)
There are many conditions and diseases that affect voice production. One of these, subglottic stenosis (SGS), is characterized by a narrowing of the trachea near the cricotracheal junction. SGS causes dyspnea (labored breathing) and frequently surgery is necessary to eliminate the airway obstruction. SGS is also believed to adversely affect voice quality. While significant research has been conducted to study the effect of SGS on breathing, relatively few studies concerning its effect on voice production have been performed. The purpose of this research was to provide quantitative results concerning the predicted effects of SGS on vocal fold (VF) vibration and resulting sound production, and to provide tools for more extensive research involving synthetic VF models in the future. This was achieved through an experimental procedure in which a device simulating SGS was coupled with synthetic VF models and acoustic, aerodynamic, and vibratory measurements were acquired. Additionally, a device was developed and tested to study the effects of VF posturing using synthetic VF models. The design of the device is anticipated to serve as a useful tool in future experiments.The device simulating SGS was capable of creating an artificial stenosis of adjustable severity. The device was designed so that synthetic VF models inserted into rigid plates could be placed on top of the device, downstream of the stenosis. An experiment was conducted with the SGS device in conjunction with synthetic four-layer VF models in which flow and pressure were measured, radiated sound data were recorded, and visual data from a high-speed camera were captured as the percent obstruction was changed. The effects of subglottic stenosis were quantified using metrics such as onset pressure, glottal area, smoothed cepstral peak prominence (CPPS), harmonic-to-noise ratio (HNR), acoustic spectra, air flow, and pressure below and above the stenosis. The results show that the glottal area was not noticeably affected by the stenosis until 80% or 90% obstruction, and flow resistance through the stenosis was not significantly affected until 85% obstruction. However, changes in acoustics occurred as low as 65% or 70% obstruction.An MRI-compatible posturing device was developed which was capable of causing abduction/adduction and elongation in synthetic VF models. The device was used to adduct synthetic VF models from an abducted position into a pre-determined final phonatory posture as high-speed video and pressure data were collected. The device adducted to final phonatory posture in 500 ms, and phonation was initiated 680 ms later. In addition, the elongation of the synthetic models was varied as high-speed data were collected. The frequency of vibration of the four-layer models was found to not vary significantly when the models were elongated.
403

GROWING OLD AS A ROCK STAR: A FOUR-PART STUDY OF THE AGING VOICE

Sloggy, JoAnna 01 January 2019 (has links)
This dissertation focuses on the aging voice - specifically the aging elite vocal athlete. It is comprised of four components; a series of research studies and a viewpoint piece designed to explore the awareness, struggles, and vocal compensations of aging singers dealing with age related vocal and performance problems. The overarching goal of these studies is to inform the development of a voice care protocol for the aging rock star to guide customized intervention for these elite vocal athletes that is focused on optimizing both vocal output and performance. First, the dissertation introduces and identifies characteristics of the exceptional voice. This involves a new vocal continuum that includes the normal voice, the trained voice, and the exceptional voice. The second component is a qualitative study of older contemporary commercial music (CCM) singers adjustments and accommodations associated with their aging. From this, four overarching themes are identified: modest self-perception of their vocal prowess and its relationship to performance, acute sensitivity to changes in vocal quality, recognition of the critical association of voice quality with their identity as a performer, and an array of accommodations to aging-related vocal changes. The third component of the dissertation is a randomized control trial examining the efficacy of Vocal Function Exercises as a treatment modality for presbyphonia. Analysis revealed that the experimental group improved in select outcome measures including decreased glottic gap, increased upper range, and maximum phonation time at the 6-week post-treatment re-evaluation with no such changes in the control group. The final study investigated the vocal and performing trajectories of six CCM male singers through analysis of video performances across their career. Singers were shown to make accommodations consistent with the reported findings from component two. Such accommodations include decreased total time singing for some singers, accommodations for range changes, and changes to performance. From this study, the Exceptional Voice Protocol was created to provide a customized vocal and performance blueprint for each artist that meets their unique needs for their exceptional voices. Overall, this research indicates that aging CCM singers appear to be experiencing age and performance related vocal changes and are making detectable accommodations to their performance. Additional findings show that Vocal Function Exercises appear to be an efficacious treatment modality for aging voice. Findings from these studies confirm the need for continued research on age-related vocal and performance changes for these performers and guidelines for appropriate habilitation and rehabilitation so these rock stars can continue performing for as long as they desire.
404

The Effects of Amplification and Selected Vocal Exercises on the Perceived Vocal Health of Elementary Music Educators.

Vincent, Lynette Susanne 05 1900 (has links)
The main purpose of this study was to consider the effects of amplification and vocal function exercises on the perceived vocal health of elementary music educators (N = 37) from Oklahoma (n = 11) and Texas (n = 26). Participants were assigned to the use of the ChatterVoxTM amplifier or vocal function exercises based on pretest scores on the Voice Handicap Index with Music Teacher Voice Questionnaire (VHI/MVQ). Following the 4-week study period, participants completed the posttest VHI/MVQ. The results of a one-way ANCOVA that used treatment group as the independent variable, the summed posttest scores as the dependent variable, and the summed pretest scores as the covariate or control variable indicated that there was a statistically significant difference between the adjusted means for the posttest scores, favoring the exercises group. The overall group and both treatment groups reported frequent loud voice use in work settings and in public places. The overall group and the amplification group reported hoarseness after prolonged talking. The exercises group did not report as great a problem with hoarseness after prolonged talking. Secondary purposes addressed demographic variables. Women perceived greater overall vocal difficulties than men; men frequently reported specific vocal complaints that were not commonly indicated by women. The vocal problems of women may have been associated with loud voice use. The following common vocal complaints of men may have been related to the use of falsetto while teaching: need for vocal rest, worse voices in the evening, dry throats, loss of voice, obvious pitch breaks in their singing voices, pain after singing for an extended time, and limited use of their high range. VHI/MVQ scores indicated that the study participants with 21 to 39 years of teaching experience had more vocal difficulties than other participants and indicated limited use of the low range of their speaking voices, inconsistency in the sound of their voices, dry throats, throat pain after singing for a prolonged time, difficulty singing softly, and the need for vocal rest. Participants with 6 or more years of experience experienced hoarseness after speaking for an extended time.
405

Luciano Berio's Sequenza III: The Use of Vocal Gesture and the Genre of the Mad Scene

Edwards, Patti Yvonne 08 1900 (has links)
Sequenza III was written in the mid -1960s and is widely available for study and performance, but how can this work be defined? Is it a series of sounds, or phonemes, or the anxious mutterings of a woman? Is it performance art or an operatic mad scene? Sequenza III could be all of these or something else entirely. Writing about my method of preparation will work to allay some of my own and other performer's fears about attempting this unusual repertory. Very little in this piece is actually performed on pitch, and even then the pitches are not definite. The intervals on the five-line staff are to be observed but the singer may choose to sing within her own vocal range. The notation that Berio has used is new and specific, but the emotional markings and dynamics drawn from these markings permit a variety of interpretive decisions by the performer. There is a very brief text and no actual melody, so where does one begin? As a composer, Berio was often responsive to external stimuli. Quotation of his earlier works and the works of others was a common tool of his technique. By comparing Sequenza III with other works by the same composer, I will delineate some borrowed features and techniques from his earlier music and from the areas of literature and visual art. Sequenza III, although available on several recordings, is still not performed very often outside the academic community. There is only a small body of scholarly literature about Luciano Berio. I hope to add to the knowledge about this recently deceased composer and his music, to create a comfort zone for singers in approaching this work, to understand the composer's intentions, and to provide a fair representation of his ideas in public performance.
406

Säg Bob! : Sex sångare om nedsjungning

Johansson, Joel January 2021 (has links)
Detta är en kvalitativ studie med kvantitativa inslag med syftet att undersöka sångares upplevelser avnedsjungning efter högintensiv sång. Till en början har specifikt designade sångövningar förmedlats till sex medverkande sångare om fyra kvinnor och två män under individuella sånglektioner. Deltagarna har i en variant av crossover design skattat sin dagliga rösthälsa i EASE- självskattningsformulär för friska röster. Testperioden om tre veckor följdes sedan av kvalitativa intervjuer. Resultat visar att även om sångares vardag är komplex, i och med inre och yttre påverkande faktorer, har nedsjungning en upplevd effekt i avseendet förbättrad rösthälsa efter högintensiv sång. Detta gäller särskilt de kvinnliga sångarna som beskriver att nedsjungning bidragit till en mer samlad röst med minskad heshet och svullnad. Vidare rapporteras om större lätthet inför att sjunga i lägre delen av bröstregistret, en mer egaliserad röst och en förbättrad tal- och magstödsteknik tillsammans med större lätthet inför påföljande sångpass. Nedsjungning ses också ha skapat ett andrum i vardagen där minskad stress, prestationskrav och resultatinriktning omvänts till en samlad känsla av avslut. Likväl är begrepp som nedsjungning, att sjunga ned, kyla ned, eller att stretcha rösten nya begrepp som rekommenderas att vidare studeras och förmedlas till elever och studenter, framför allt då föreliggande studies resultat visar tydliga attitydskillnader avseende rösthälsa och röstvård emellan de olika könen. / This is a study regarding singers' experiences of a vocal-cool down routine preceded with a heavy vocal load. The study is mainly based on a qualitative approach with quantitative elements. At first individual singing lessons where held, whereas specifically designed vocal-cool down exercises were taught to six participating singers; four women and two men. With a modification of a crossover design the singers in this study have estimated their daily voice health in the Evaluation of the Ability to Sing Easily survey (EASE). After a three week period of tests the singers were interviewed. The result of this study shows that even if singers' everyday lives are complex due to internal and external factors, vocal- cool down where perceived as an improvement of voice health. It is mainly the female singers' that describes an increased vocal well-being, with less hoarseness and swollen vocal folds after a heavy vocal load, followed by a vocal -cool down routine. Furthermore a greater sense of ease was reported in terms of transitions between registers in the singing voice, where fatigue in the surrounding muscles also decreased alongside with a positive impact on the speaking voice, reaching lower notes in chest register and extended diaphragm breathing. The vocal cool-down routine itself also gave an unexpected finding in terms of being contemplative and relaxing for the singers; creating a breathing space in everyday life where stress, performance anxiety and other concerns where easier to let go of, with an overall feeling of closure. Vocal cool down, cooling down the voice, vocal stretch, or warming down your voice are all relatively new concepts that are recommended to be studied further, spread and taught to students and pupils, - especially as the result in this study indicates clear differences in attitudes regarding voice health in-between the male and female genders.
407

Internal Deformation Measurements and Optimization of Synthetic Vocal Fold Models

Taylor, Cassandra Jeanne 01 December 2018 (has links)
Developing lifelike vocal fold models is challenging due to various associatedbiomechanical complexities. Nevertheless, the development and analysis of improved vocal foldmodels is worthwhile since they are valuable tools for gaining insight into human vocal foldvibratory, aerodynamic, and acoustic response characteristics. This thesis seeks to contribute tothe development of computational and physical vocal fold modeling in two ways. First is byintroducing a method of obtaining internal deformation fields within vibrating synthetic vocal foldmodels; second is by presenting an optimization algorithm coupled with a computational vocalfold model to optimize geometry and stiffness of a synthetic vocal fold model to achieve morerealistic vibration patterns.The method for tracking the internal deformation of self-oscillating vocal fold models isbased on MR imaging. Silicone models scaled to four times life-size to lower the flow-inducedvibration frequency were imbedded with fiducial markers in a coronal plane. Candidate markermaterials were tested using static specimens, and two materials, cupric sulfate and glass, werechosen for testing in the vibrating VF models. The vibrating models were imaged using a gatedMRI protocol wherein MRI acquisition was triggered using the subglottal pressure signal. Twodimensionalimage slices at different phases during self-oscillation were captured, and in eachphase the fiducial markers were clearly visible. The process was also demonstrated using a threedimensionalscan at two phases. The benefit of averaging to increase signal-to-noise ratio wasexplored. The results demonstrate the ability to use MRI to acquire quantitative deformation datathat could be used, for example, to validate computational models of flow-induced VF vibrationand quantify deformation fields encountered by cells in bioreactor studies.A low fidelity, two-dimensional, finite element model of VF flow-induced vibration wascoupled with a custom MATLAB-based genetic algorithm optimizer. The objective was to achievea closed quotient within the normal human physiological range. The results showed that changesin geometry and stiffness would lead to a model that exhibited the desired characteristics. Aphysical model based on optimized parameters was then fabricated and the closed quotient wastested. The physical model successfully vibrated with nonzero closed quotient as predicted by thecomputational model.
408

Production and perception of acoustic signals in captive bottlenose dolphins (Tursiops truncatus) : contextual use of social signals and recognition of artificial labels / Production et perception des signaux acoustiques chez les grands dauphins (Tursiops truncatus) : utilisation contextuelle des signaux sociaux et reconnaissance de « labels » artificiels

Lima, Alice de Moura 15 December 2017 (has links)
Les études de bioacoustique animale, qui reposent traditionnellement sur des modèles primates non humains et oiseaux chanteurs, convergent vers l'idée que la vie sociale serait la principale force motrice de l'évolution de la complexité de la communication. La comparaison avec les cétacés est également particulièrement intéressante d'un point de vue évolutif. Ce sont des mammifères qui forment des liens sociaux complexes, ont des capacités de plasticité acoustique, mais qui ont dû s'adapter à la vie marine, faisant de l'habitat une autre force de sélection déterminante. Leur habitat naturel impose des contraintes sur la production sonore, l'utilisation et la perception des signaux acoustiques, mais, de la même manière, limite les observations éthologiques. Etudier les cétacés captifs devient alors une source importante de connaissances sur ces animaux. Au-delà de l'analyse des structures acoustiques, l'étude des contextes sociaux dans lesquels les différentes vocalisations sont utilisées est essentielle à la compréhension de la communication vocale. Par rapport aux primates et aux oiseaux, la fonction sociale des signaux acoustiques des dauphins reste largement méconnue. En outre, les adaptations morpho-anatomiques de l’appareil vocal et auditif des cétacés à une vie sous-marine sont uniques dans le règne animal. Leur capacité à percevoir les sons produits dans l'air reste controversée en raison du manque de démonstrations expérimentales. Les objectifs de cette thèse étaient, d'une part, d'explorer l'utilisation contextuelle spontanée des signaux acoustiques dans un groupe captif de dauphins et, d'autre part, de tester expérimentalement les capacités à percevoir les sons sous l’eau comme dans l’air. Notre première étude observationnelle décrit la vie quotidienne de dauphins en captivité et montre que les signaux vocaux reflètent, à grande échelle, la répartition temporelle des activités sociales et non sociales dans un établissement sous contrôle humain. Notre deuxième étude met l'accent sur le contexte d’émission des trois principales catégories acoustiques précédemment identifiées dans le répertoire vocal des dauphins, à savoir les sifflements, les sons pulsés et les séries de clics. Nous avons trouvé des associations préférentielles entre chaque catégorie vocale et certains types d'interactions sociales ainsi que des combinaisons sonores non aléatoires et également dépendantes du contexte. Notre troisième étude a testé expérimentalement, dans des conditions standardisées, la réponse des dauphins à des « labels » acoustiques individuels donnés par l’homme et diffusés dans l’eau et dans l’air. Nous avons constaté que les dauphins peuvent reconnaître et réagir uniquement à leur propre « label » sonore, même lorsqu'il est diffusé dans l’air. En plus de confirmer l'audition aérienne, ces résultats soutiennent l’idée que les dauphins possèdent une notion d'identité. Dans l'ensemble, les résultats obtenus au cours de cette thèse suggèrent que certains signaux sociaux dans le répertoire des dauphins peuvent être utilisés pour communiquer des informations spécifiques sur les contextes comportementaux des individus impliqués et que les individus sont capables de généraliser leur concept d'identité à des signaux générés par l'homme. / Studies on animal bioacoustics, traditionally relying on non-human primate and songbird models, converge towards the idea that social life appears as the main driving force behind the evolution of complex communication. Comparisons with cetaceans is also particularly interesting from an evolutionary point of view. They are indeed mammals forming complex social bonds, with abilities in acoustic plasticity, but that had to adapt to marine life, making habitat another determining selection force. Their natural habitat constrains sound production, usage and perception but, in the same way, constrains ethological observations making studies of captive cetaceans an important source of knowledge on these animals. Beyond the analysis of acoustic structures, the study of the social contexts in which the different vocalizations are used is essential to the understanding of vocal communication. Compared to primates and birds, the social function of dolphins’ acoustic signals remains largely misunderstood. Moreover, the way cetaceans’ vocal apparatus and auditory system adapted morphoanatomically to an underwater life is unique in the animal kingdom. But their ability to perceive sounds produced in the air remains controversial due to the lack of experimental demonstrations. The objectives of this thesis were, on the one hand, to explore the spontaneous contextual usage of acoustic signals in a captive group of bottlenose dolphins and, on the other hand, to test experimentally underwater and aerial abilities in auditory perception. Our first observational study describes the daily life of our dolphins in captivity, and shows that vocal signalling reflects, at a large scale, the temporal distribution of social and non-social activities in a facility under human control. Our second observational study focuses on the immediate context of emission of the three main acoustic categories previously identified in the dolphins’ vocal repertoire, i.e. whistles, burst-pulses and click trains. We found preferential associations between each vocal category and specific types of social interactions and identified context-dependent patterns of sound combinations. Our third study experimentally tested, under standardized conditions, the response of dolphins to human-made individual sound labels broadcast under and above water. We found that dolphins were able to recognize and to react only to their own label, even when broadcast in the air. Apart from confirming aerial hearing, these findings go in line with studies supporting that dolphins possess a concept of identity. Overall, the results obtained during this thesis suggest that some social signals in the dolphin repertoire can be used to communicate specific information about the behavioural contexts of the individuals involved and that individuals are able to generalize their concept of identity for human-generated signals.
409

Development and Analysis of 3D-Printed Synthetic Vocal Fold Models

Romero, Ryan Gregory 01 August 2019 (has links)
Vocal fold models are valuable for studying voice production. They provide an alternative method of studying the mechanics of the voice that does not require in vivo experimentation or the use of excised human or animal tissue. In this thesis, a new method of creating vocal fold models through additive manufacturing is described. The purpose of this research was to reduce model fabrication time, to decrease the number of model failures during manufacturing, and to lay the foundation for creating models with more lifelike geometric and material properties. This research was conducted in four stages. First, a suitable silicone additive manufacturing technique using a UV-curable silicone was chosen. The technique chosen was called freeform reversible embedding (FRE) and involved embedding liquid silicone material into a gel-like medium named organogel. The UV-curable silicone's material properties were identified to confirm its utility in vocal fold model design. Second, an open-source, fused deposition modeling slicing software was selected to create g-code for the printer. Applicable software settings were tuned through qualitative printing tests to find their optimal values for use in FRE printing. Third, 3D-printed cubes were used in tensile tests to characterize the material properties of FRE-printed, silicone material. The cubes were found to be anisotropic, exhibiting different modulus values corresponding to the layer orientation of the printed material. Fourth, vocal fold models were FRE-printed in two different layer orientations and were used in phonation tests to gather data for onset pressure, vibratory frequency, amplitude, and flow rate. The printed models self-oscillated and withstood the strains induced by phonation. These tests showed that layer direction affects the phonation properties of the models, demonstrating that models with layers in the coronal plane had slightly lower frequencies and onset pressures than models with layers in the sagittal plane. The models' onset pressures were higher than what is found in human vocal folds. However, their frequencies were within a comparable range. These tests showed the effectiveness of additive manufacturing in the application of vocal fold fabrication, reducing production effort by allowing researchers to go directly from model design to fabrication in a single manufacturing step. It is anticipated that this method will be modified to incorporate printing of multiple stiffnesses of silicone to better mimic the material properties of vocal fold tissue, and that the anisotropy of 3D-printed material will be leveraged to model the anisotropy of human vocal folds. This work also has potential application areas outside of voice research.
410

Vocal Health: Awareness and Perceptions in Undergraduate Vocal Music and Theatre Majors

Smith, Heather 01 May 2018 (has links)
Objective: The purpose of this study was to identify the perceptions of students majoring in vocal music and theatre regarding the instruction they receive in their undergraduate curricula on voice health education. Methods: A survey was adapted from a previous study, Beeman (2016), with permission by the author. The survey was disseminated to undergraduate vocal music and theatre majors across the United States via SurveyMonkey®, an online survey tool. Results: Students perceived receiving knowledge on vocal health from their voice teachers, however they reported low levels of vocal hygiene compliance. Additionally, students recognized the connection between the singing and speaking voice, and they were unclear of the role of the speech-language pathologist in voice. Conclusion: The disconnect between vocal health knowledge and student compliance of vocal hygiene strategies, requires further investigation. Utilizing the voice care team, specifically the speech-language pathologist, to educate both the voice teachers and the students on best practices, is imperative.

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