Tesi sul tema "Anatomy of tongue"

The aim of this study was to quantify the density of taste pores on the anterior region of the tongue, in adult males and 8 to 9 year old boys. Earlier studies had shown that, although 8 to 9 year olds were poorer than adults at sensing the tastant sucrose using a whole mouth procedure, localised regions of the tongue in male children were more sensitive than equivalent regions in adults. This study aims to detemine whether the age differences in sensitivity is related to a difference in taste pore density. Two areas of the tongue, for which children had previously been shown to have higher sensitivity than adults, were examined using a videomicrosocpy technique and the number and diameter of taste pores were measured. Children were found to have a greater density of taste pores, however the number of taste pores per papilla were similar in children and adults. It was found to be likely that the greater sensitivity of localised areas on the children's tongue is due to a greater taste pore density. The reduced sensitivity reported using whole mouth stimulation may be due to a reduced capacity to assimilate taste input from the whole mouth or due to different relative contributions to whole-mouth taste from the various receptive fields in the mouth.
Master of Science (Hons)

The aim of this study was to quantify the density of taste pores on the anterior region of the tongue, in adult males and 8 to 9 year old boys. Earlier studies had shown that, although 8 to 9 year olds were poorer than adults at sensing the tastant sucrose using a whole mouth procedure, localised regions of the tongue in male children were more sensitive than equivalent regions in adults. This study aims to detemine whether the age differences in sensitivity is related to a difference in taste pore density. Two areas of the tongue, for which children had previously been shown to have higher sensitivity than adults, were examined using a videomicrosocpy technique and the number and diameter of taste pores were measured. Children were found to have a greater density of taste pores, however the number of taste pores per papilla were similar in children and adults. It was found to be likely that the greater sensitivity of localised areas on the children's tongue is due to a greater taste pore density. The reduced sensitivity reported using whole mouth stimulation may be due to a reduced capacity to assimilate taste input from the whole mouth or due to different relative contributions to whole-mouth taste from the various receptive fields in the mouth.

L'objectif de cette thèse est l'étude des interactions mécaniques entre la langue et le palais dans la production de parole et la déglutition. Cette interaction est cruciale car elle détermine la morphologie de la langue et son évolution dans le temps avant et après les contacts. Elle ne peut cependant pas être étudiée avec des approches cinématiques conventionnelles, car l'amplitude des mouvements est trop faible. La première partie de la thèse est consacrée à la conception d'un dispositif expérimental permettant de mesurer ces interactions sans perturber l'appareil vocal. La première particularité est que le dispositif est utilisé sur des patients édentés appareillés. Nous utilisons un duplicata de la prothèse complète maxillaire pour insérer des capteurs miniatures à jauges de contrainte dont les caractéristiques de réponse sont optimisées et qui permettent de mesurer la pression mécanique exercée par la langue sur le palais. La seconde particularité est qu’il existe une procédure d'étalonnage, associée aux capteurs, qui utilise une Colonne d’Eau Sèche. Elle applique une pression sur le capteur via une membrane en latex déformable, capable de simuler le comportement visco-élastique de la langue sur le palais. La deuxième partie de la thèse décrit le protocole de recherche clinique visant à (1) caractériser l'interaction langue-palais au cours de la prononciation et de la déglutition normales sur des individus édentés que nous considérons adaptés à leur prothèse complète (Cohorte 1), (2) observer l'adaptation dans une étude longitudinale des patients édentés nouvellement appareillés (Cohorte 2). Ce projet comprend, pour les deux cohortes, la description des objectifs, le protocole expérimental, la description fine des paramètres pertinents et la méthode statistique de traitement des données. Toutefois, le processus de rédaction et de soumission de ce protocole à un Comité de Protection des Personnes (CPP) a été plus long que prévu et l’étude clinique n’a pu être menée dans le cadre de cette thèse. C’est pourquoi, dans la troisième partie de la thèse, nous avons utilisé les données enregistrées dans l’étude de faisabilité, auprès d'un adulte édenté francophone. Les résultats montrent que notre dispositif permet d'explorer des hypothèses théoriques cruciales dans la parole comme l'existence de cibles virtuelles au-dessus du palais ou le rôle du palais dans la mise en forme du conduit aérien des consonnes fricatives. Les résultats des données enregistrées lors de la déglutition sont moins clairs, mais l'enchaînement temporel précis des contacts peut être décrit, ce qui permet de préciser comment les mouvements ondulatoires de la langue pendant la phase orale de la déglutition exploitent les contacts avec le palais. Les retombées cliniques de cette thèse permettent une meilleure connaissance du rôle fonctionnel des prothèses complètes et d’envisager la conception de prothèses qui seraient adaptées aux spécificités de chaque patient, notamment pour la rééducation des sujets traités chirurgicalement après des cancers de la langue, dans le cadre des taches de production de parole et de déglutition
The aim of the thesis is the study of the mechanical interaction between tongue and palate in speech production and swallowing. This interaction is crucial since it determines the shape of the tongue and its time evolution before and after contacts occur. Yet it cannot be studied with conventional kinematic approaches, since magnitude of movements is too small. The first part of the thesis was devoted to the design of an experimental setup to measure this interaction without perturbing the vocal tract. The first specificity is that the setup is used on subjects who are edentulous and wear a complete denture. We use a duplicate of the complete denture to insert miniature strain gauge sensors with enhanced response characteristics, that enable the measure of the mechanical pressure exerted by the tongue in different locations of the palate, without altering the shape of the palatal arch. The second specificity is that the calibration procedure uses a Dried Water Column (DWC) that applies pressure on the sensor via a deformable latex membrane, that simulates the way tongue touches the palate. The second part of the thesis enabled the design of an experimental protocol aiming at (1) providing a characterization of the tongue-palate interaction in normal speech production and swallowing based on edentulous subjects whom we consider to have adapted to their complete denture (cohort 1), (2) observing the adaptation process in a longitudinal study of edentulous subjects who are new users of complete denture (cohort 2). This work includes for two cohorts the design of the subject inclusion criteria, the motor tasks and the statistical method for the data analysis. However, unforeseen long delays were faced in the application process for the ethical approval and no data were collected in this context. Hence the third part of the thesis used data recorded in our most recent pilot study, with a French speaking edentulous adult. It is shown that our setup makes possible to tackle crucial theoretical questions in speech production such as the existence of virtual targets above the palate in stops or the role of the palate in the air channel shaping in fricatives. Results of swallowing tasks are less clear, but it is shown that precise time sequencing of contacts can be described, making possible the specification of how the ondulatory movements of the tongue in the oral phase of swallowing takes advantage of palatal contacts. In conclusion implications of this thesis are presented for a functional assessment of complete dentures, and the design of dentures that would be adapted to each subject’s specificities

Comprendre et mieux définir la pathophysiologie de l'asthme est essentiel au développement de traitements plus efficaces. L'hyperréactivité bronchique et le tonus élevé du muscle lisse entourant les voies respiratoires sont deux caractéristiques majeures de l'asthme. Si une causalité existe entre ces caractéristiques, elle demeure encore inconnue. Le travail présenté dans ce Mémoire décrit comment un tonus, induit par un spasmogène, affecte la réactivité bronchique à une bronchoprovocation in vivo chez la souris. La capacité contractile de trachées murines excisées a aussi été mesurée afin d'évaluer si la réponse obtenue in vivo implique le muscle lisse. Les résultats présentés dans ce mémoire démontrent qu'in vivo, les souris exposées à un tonus voient leur réactivité bronchique augmenter en réponse à une dose d'un spasmogène, comparées aux souris contrôles. Les résultats démontrent également que la réponse obtenue est causée, du moins en partie, par une augmentation de la capacité contractile du muscle lisse. Suite à ces résultats, les mécanismes moléculaires possiblement impliqués dans le gain de force induit par le tonus ont été investigués. L'hypothèse est que les voies de signalisation en aval de l'activation des récepteurs couplés aux protéines G sont responsables de l'augmentation de la capacité contractile du muscle lisse. L'inhibition de la polymérisation de l'actine, l'activation de la chaîne légère de myosine, l'activation de protéines G et l'inhibition des protéines kinases activées par les mitogènes ont donc été évaluées. Les résultats démontrent qu'aucune des voies de signalisation étudiées est impliquée dans le gain de force du muscle lisse provoqué par un tonus induit par la présence continue d'un spasmogène. Ces résultats démontrent la complexité que représente la recherche des mécanismes moléculaires du gain de force et que cette recherche doit être plus approfondie.
To understand and better define the pathophysiology of asthma is essential for the development of more effective treatments. Airway hyperresponsiveness and an elevated airway smooth muscle tone are two common features of asthma. Whether causality exists between these two characteristics is unknown. The work presented in this Master's thesis describes how a tone induced by a spasmogen affects airway responsiveness in vivo in mice to a spasmogenic challenge. The contractile capacity of excised murine tracheas was also measured to evaluate whether the obtained response in vivo involved airway smooth muscle. The results presented in this Master's thesis demonstrate that mice exposed to tone in vivo have an increased response to a high dose of a spasmogen, compared to control mice. The results also show that this response is caused, at least partly, by an increase in airway smooth muscle contractile capacity. Following these results, molecular mechanisms possibly involved in the gain in force induced by tone were investigated. It was hypothesized that signaling pathways downstream of G protein-coupled receptors were responsible for the increase in airway smooth muscle contractile capacity. Therefore, the inhibition of actin polymerization, the activation of myosin lightchain, the activation of G proteins, and the inhibition of mitogen-activated protein kinases were evaluated to assess whether they mediate the gain in force induced by tone. The results show that none of the pathways studied were implicated in the gain in force induced by tone elicited by the continuous presence of a spasmogen. These latter results demonstrate that the mechanisms leading to a gain in airway smooth muscle force following an induced tone are complex and will require further investigation.

INTRODUÇÃO: A apneia obstrutiva do sono (AOS) é um problema de saúde pública, com grande prevalência e graves consequências. O tratamento considerado padrão-ouro para AOS grave é a aplicação do aparelho de pressão positiva aérea contínua (CPAP) durante o sono. Porém a adesão ao CPAP é baixa, em especial nos pacientes com ronco primário e AOS leve. Estudo prévio do nosso laboratório demonstrou que a terapia miofuncional orofacial (TMO) é efetiva em pacientes com AOS moderada (Guimaraes et. al, AJRCCM 2009:(179);962-966). No entanto, no trabalho inicial o número de pacientes foi relativamente pequeno (n=31), avaliou-se apenas pacientes com AOS moderada. Adicionalmente, a quantidade de exercícios orofaríngeos realizados foi relativamente grande (n=10) dificultando a adesão ao tratamento e os potenciais mecanismos de ação da terapia não foram elucidados. OBJETIVO: O objetivo primário do trabalho é avaliar a efetividade na redução da gravidade da AOS de um programa com um número reduzido de exercícios de TMO (6 exercícios) em pacientes com ronco primário, AOS leve, moderada e grave. Os objetivos secundários foram avaliar o impacto da TMO no índice de apneia hipopneia (IAH) em pacientes estratificados pelo IAH basal, a anatomia da via aérea superior (VAS) por meio da ressonância magnética (RM), a fisiologia da VAS por meio da força e fadiga da língua e a pressão crítica de fechamento (Pcrit). METODOLOGIA: Foram incluídos pacientes de ambos os sexos, com idade entre 20 e 65 anos, recentemente diagnosticados com ronco primário, AOS leve, moderada ou pacientes com AOS grave que se recusaram a utilizar o CPAP. Foram excluídos pacientes com índice de massa corpórea (IMC) >= 35 kg/m2, malformações craniofaciais, desdentados, uso regular de medicação hipnótica, doença obstrutiva nasal grave, pacientes já submetidos a outros tipos de tratamentos e pacientes com indisponibilidade de comparecimento semanal durante o estudo. Os pacientes foram avaliados no início e final do estudo por questionário de sonolência (Epworth, variando de 0 a 24 pontos), qualidade de sono (Pittsburgh, variando de 0 a 21 pontos), avaliação fonoaudiológica específica para AOS (variando de 0 a 20 pontos), RM da via aérea superior, força e fadiga de língua, Pcrit e polissonografia. Os pacientes foram sorteados para 3 meses de TMO (6 exercícios) ou controle (dilatador nasal durante o sono e exercícios respiratórios inespecíficos). Todos os pacientes foram acompanhados semanalmente por uma fonoaudióloga e orientados a realizar os exercícios três vezes por dia. Foi realizada ANOVA de dois caminhos para medidas repetidas para avaliar a eficácia dos tratamentos nos diferentes desfechos. Secundariamente também avaliamos o efeito dos tratamentos por meio do teste t pareado. RESULTADOS: Inicialmente 251 pacientes foram avaliados, e após avaliação dos critérios de inclusão e exclusão, 60 pacientes entraram no estudo, sendo que 30 foram randomizados para TMO e 30 para o grupo Controle. Os dois grupos foram semelhantes para todos os parâmetros na entrada. Finalizaram o estudo 58 pacientes (58,6% do sexo masculino, média de idade 45,9 ± 12,2 anos, IMC 28,8 ± 4,3 kg/m2, IAH=18,4 ± 12,6 eventos/h e saturação mínima de oxigênio 84,6 ± 6,4%). O grupo Controle não teve modificações em nenhuma das variáveis ao longo do estudo. O grupo TMO não modificou o IMC e não apresentou mudança significativa nos questionários Epworth e Pittsburgh. Em relação ao início do estudo, o grupo TMO apresentou uma redução significativa na circunferência cervical (38,8±3,3 vs 38,4±4 cm), índice de despertar (21,3±10,9 vs 16,9±7,9 despertares/h), IAH (19,5 ± 14,2 vs 15 ± 10,2 eventos/h) e avaliação fonoaudiológica específica para AOS (9,3 ± 2,9 vs 3,6 ± 2,4). O efeito da TMO sobre o IAH foi significativo somente nos pacientes que apresentavam na entrada AOS moderada (23,8 ± 5,2 vs 17,7 ± 5,2) e grave (43,9 ± 19,5 vs 24,7 ± 21,4). Não foram observadas modificações significativas quando avaliado por meio do teste de ANOVA de duas vias para medidas repetidas na RM da via aérea superior em 24 pacientes (10 Controle e 14 TMO) e fisiologia avaliados por força e fadiga de língua em 38 pacientes (19 Controle e 19 TMO) e Pcrit em 17 pacientes (7 Controle e 10 TMO). No entanto, observamos uma redução significativa (teste t pareado) com diminuição do volume da língua (p=0.031), quantidade de gordura da língua (p=0.008) e aumento significativo da força da língua (p=0,046) no grupo TMO. CONCLUSÃO: Um programa reduzido de TMO é efetivo e capaz de reduzir a gravidade da apneia do sono em pacientes com AOS moderada e grave. A tendência ao aumento da força de língua e redução da gordura de língua podem auxiliar a explicar os efeitos benéficos da TMO em pacientes com AOS
INTRODUCTION: Obstructive sleep apnea (OSA) is a public health problem, with high prevalence and severe consequences. The gold standard treatment for severe OSA is the application of continuous positive airway pressure (CPAP) during sleep. However, adherence to CPAP is low, especially in patients with primary snore and mild OSA. A previous study from our laboratory demonstrated that oropharyngeal exercises are effective in patients with moderate OSA (Guimaraes et. al, AJRCCM 2009:(179);962-966). Nonetheless, in this first study the number of patients included in the randomized trial was relatively small (n=31) and evaluated only patients with moderate OSA. Moreover, the number of oropharyngeal exercises the patients had to do 3 times a day was large (n=10) and raised doubt about the compliance to treatment, and the mechanism by which the therapy was effective was not elucidated. OBJECTIVE: The primary objective was to evaluate the effectiveness to reduce OSA severity of a short program of oropharyngeal exercises (6 exercises) in patients with primary snore, mild, moderate and severe OSA. The secondary objective was to evaluate the impact of reduced oropharyngeal exercises program on apnea hypopnea index (AHI) in patients stratified by baseline AHI, the anatomy of upper airway by magnetic resonance (MR), strength and fatigue of the tongue and critical closing pressure (Pcrit). METHODOLOGY: Patients of both sexes, with age between 20 and 65 years old, recently diagnosed with primary snore, mild, moderate or severe OSA who refused to use CPAP were included. Patients with body mass index (BMI) >= 35kg/m2, craniofacial deformities, edentulous, regular use of hypnotic medication, severe nasal obstruction, patients undergoing other treatments for OSA and patients with unavailability to comply with the protocol were excluded. The patients were evaluated at the beginning and end of the study by questionnaire of daytime sleepiness (Epworth, ranging from 0 to 24 points), quality of sleep (Pittsburgh, ranging from 0 to 21 points), oral myofunctional evaluation for OSA (ranging from 0 to 20 points), MR of the upper airway, tongue strength and fatigue, critical closing pressure (Pcrit) and polysomnography. The patients were randomized to 3 months of oropharyngeal exercises (6 exercises) or Control (use of nasal dilator strip and respiratory non specific respiratory exercises). All patients were instructed to perform the exercises 3 times a day and evaluated by a speech pathologist once a week. The primary endpoints were evaluated primarily by two-way repeated-measures ANOVA. A paired t test was also used as a secondary evaluation. RESULTS: A total of 251 patients were evaluated and 60 patients were randomized. The 2 groups (n=30) were similar at study entry for all the parameters and 58 patients completed the study (58.6% males, age: 45.9±12.2 years, BMI: 28.8±4.3 kg/m2, AHI=18.4±12.6 events/h and minimum saturation84.9±6.4%). All variables remained unchanged in the Control group. There were no changes in Epworth and Pittsburgh questionnaires as well as BMI in patients randomized to oropharyngeal exercises. As compared to study entry, there was a significantly reduction on neck circumference (38.8 ± 3.3 vs 38.4±4.4cm), arousals index (21.3 ± 10.9 vs 16.9 ± 7.9 arousals/h), AHI (19.5 ± 14.2 vs 15 ± 10.2 events/h), oral myofunctional evaluation for OSA (9.3 ± 2.9 vs 3.6 ± 2.4) in the patients randomized for oropharyngeal exercises. Oropharyngeal exercises only reduced AHI significantly among patients with moderate OSA (23.8 ± 5.2 vs 17.7 ± 5.2) and severe OSA (43.9 ± 19.5 vs 24.7 ± 21.4) at study entry. No significantly changes as evaluated by two-way repeated-measures ANOVA were observed on upper airway MR anatomy (10 Control and 14 oropharyngeal exercises), tongue force and fatigue (19 Control and 19 oropharyngeal exercises) and Pcrit (7 Control and 10 oropharyngeal exercises). As compared to study entry there was a significant reduction as evaluated by paired T test on tongue volume (p=0.031), tongue fat (p=0.008) and a significant increase of tongue strength (p=0.046) of patients randomized to oropharyngeal exercises. CONCLUSION: A short program of oropharyngeal exercises is effective to reduce OSA severity in patients with moderate and severe OSA. The trend to increase tongue strength and reduce tongue fat may explain the beneficial effects of oropharyngeal exercises

Le système langue-palais est capable de détecter de fines variations de texture en bouche là où le meilleur des rhéomètres est essentiellement aveugle. Une hypothèse pour expliquer cette remarquable sensibilité repose sur la présence de myriades de papilles filiformes sur la surface de la langue et de mécanorécepteurs à leur base. Pendant cette thèse, nous avons adopté une approche biomimétique reproduisant le fonctionnement de la cavité orale. La langue est un bloc d’élastomère décoré de cylindres assimilés à des papilles filiformes. Elle est placée sur une cellule de rhéoscope, combinaison d’un rhéomètre et d’un microscope. L’outil rotatif du rhéomètre joue le rôle du palais rigide, et impose l’écoulement du liquide testé. Nous avons imagé sous cisaillement de fluides simples la déflexion d’une papille et montré que celle-ci est proportionnelle aux contraintes visqueuses, en accord avec un modèle élastohydrodynamique récent. Nous avons sondé la déflexion d’une papille en présence de suspensions granulaires, modélisant des émulsions alimentaires. Nous avons montré que la présence de particules dans la phase continue modifie peu la déformation moyenne d’une papille, mais fortement son écart-type, surtout à cause des collisions particules/papille. Enfin, nous avons étudié l’effet des interactions entre papilles en variant leur densité surfacique. Cette déflexion diminue avec la densité. Un modèle phénoménologique, qui traite le tapis de papilles comme un milieu poreux effectif, décrit avec succès nos données sur toute la gamme de densité
The tongue-palate system is able to detect fine texture variations in the mouth where the best rheometers are essentially blind. One hypothesis to explain this remarkable sensitivity is the presence of myriads of filiform papillae on the surface of the tongue and mechanoreceptors at their base. During this thesis, we developed a biomimetic approach reproducing the functioning of the oral cavity. The tongue is an elastomer block decorated with elongated cylinders assimilated to filiform papillae. It is placed on the bottom of the cell of a rheoscope, a combination of a rheometer and a microscope. The rotating rheometer tool plays the role of the rigid palate, and imposes the flow of the tested liquid. We have imaged while shearing simple fluids the deflection of a papilla and showed that it is proportional to the viscous stresses, in perfect agreement with a recent elastohydrodynamics model. We probed the deflection of a papilla in the presence of granular suspensions as models of food emulsions. We have shown that the presence of particles in the continuous phase slightly modifies the average deformation of a papilla, but strongly changes the standard deviation around this deformation, mainly because of particle/papilla collisions. Finally, we studied the effect of papillae interactions by varying their surface density. This deflection decreases with density. A phenomenological model that treats the papillae as an effective porous medium successfully describes our data across the entire density range

Several recent morphological studies have addressed the interrelationships of Osteoglossomorpha, a group that sometimes is considered the sister group of all other living teleostean fishes. Many characters used in these studies were found to be poorly defined, to be coded incorrectly or illogically, or to display more variation than was described. The goal of this study is to address these concerns and contribute generally to knowledge of the morphology and systematic relationships of osteoglossomorphs. Analysis of 72 characters scored for 20 genera resulted in 2 most parsimonious cladograms. The only difference in the topologies of these cladograms is in the position of †Lycoptera (recovered as either the sister group of all other osteoglossomorphs sampled or of †Eohiodon + Hiodon). †Ostariostoma is recovered as the sister group of all non-hiodontiform osteoglossomorphs. Mormyrids are sister group of notopterids + osteoglossids (including Pantodon). Mormyrids and notopterids usually are considered more closely related to each other than to any other group; characters not included here support this relationship and future consideration of these characters must be made. † Palaeonotopterus is interpreted as sister-group of all mormyrids sampled; however, only 22% of characters could be scored for it and its resemblance to notopterids are undeniable. General problems of character definition are discussed in my review of characters used in previous analyses.

This thesis documents the annual profiles of the primary reproductive steroids testosterone (T), 17beta-oestradiol (E2) and progesterone (P4), in the reproductive cycles of male and female blue-tongued lizards, Tiliqua nigrolutea. Data collected from a large captive population over three consecutive reproductive seasons are included. Reproductive cycles are discussed in the context of other viviparous squamate reptiles, while a broader comparative approach is used to consider patterns of steroid biosynthesis and peripheral metabolism. The annual patterns of circulating concentrations of T, E2 and P4 have been characterised for both sexes. In males, peak plasma T (10.9 +/- 3.00 ng ml-1) and E2 (778.0 +/- 120.00 pg ml-1) concentrations occur coincident with late spermatogenesis and observations of mating, respectively. Plasma P4 concentrations remain basal (< 1.2 ng ml-1) throughout the annual reproductive cycle. In females, increasing plasma E2 concentrations (275.2 +/- 33.87 pg ml-1 - 715.1 +/- 106.68 pg ml-1) are associated with vitellogenesis and plasma T peaks (6.3 +/- 0.63 ng ml-1) in the mating and peri-ovulatory period. In pregnant females, plasma P4 concentrations are elevated for the first two thirds of gestation, peaking in the second trimester at 12.7 +/- 1.27 ng ml-1 and falling rapidly prior to parturition. Concurrently, plasma P4 concentrations in non-reproductively active adult females remain basal (1 - 2 ng ml-1) throughout the year. There is good circumstantial evidence for a multiennial reproductive cycle in females. Parturition occurs late in the active season, presumably leaving little time for females to store sufficient fat reserves to become vitellogenic in the following spring: reproductive opportunities are effectively missed in at least one year following a reproductive effort. Observed reproductive behaviours, including agonistic male - male interactions, mating, and parturition, are documented. An investigation of gonadal steroid biosynthetic pathways in this viviparous squamate is presented. This compares variation in the relative contributions of the delta-4 and delta-5 steroidogenic pathways according to sex and reproductive condition. The delta-4 pathway predominates in both sexes, aligning this species phylogenetically with other reptiles. However, there are clear differences between sexes and with changing reproductive condition in the patterns of production of pathway intermediates and end-products. Additionally, detection of a possibly novel polar steroid as a major end-product of steroid biosynthesis in both sexes is reported. Peripheral (extragonadal) metabolism of T and E2 in a number of reproductively relevant steroid target tissues is compared at times of year chosen to represent three clearly distinctive reproductive conditions in each sex. There are differences both between sexes, between tissue types and with changing reproductive condition in the relative proportions of steroid conjugates and non-conjugated derivatives produced. Biosynthetic pathway activity and peripheral steroid metabolism both appear to be plastic in response to changing reproductive condition in Tiliqua nigrolutea. With a comprehensive database of information about the reproductive endocrinology and physiology of Tiliqua nigrolutea, this species is now available as a model to further examine selected aspects of the steroid hormone control of reproductive physiology and behaviour in a cool temperate, viviparous reptile.

This thesis documents the annual profiles of the primary reproductive steroids testosterone (T), 17beta-oestradiol (E2) and progesterone (P4), in the reproductive cycles of male and female blue-tongued lizards, Tiliqua nigrolutea. Data collected from a large captive population over three consecutive reproductive seasons are included. Reproductive cycles are discussed in the context of other viviparous squamate reptiles, while a broader comparative approach is used to consider patterns of steroid biosynthesis and peripheral metabolism. The annual patterns of circulating concentrations of T, E2 and P4 have been characterised for both sexes. In males, peak plasma T (10.9 +/- 3.00 ng ml-1) and E2 (778.0 +/- 120.00 pg ml-1) concentrations occur coincident with late spermatogenesis and observations of mating, respectively. Plasma P4 concentrations remain basal (< 1.2 ng ml-1) throughout the annual reproductive cycle. In females, increasing plasma E2 concentrations (275.2 +/- 33.87 pg ml-1 - 715.1 +/- 106.68 pg ml-1) are associated with vitellogenesis and plasma T peaks (6.3 +/- 0.63 ng ml-1) in the mating and peri-ovulatory period. In pregnant females, plasma P4 concentrations are elevated for the first two thirds of gestation, peaking in the second trimester at 12.7 +/- 1.27 ng ml-1 and falling rapidly prior to parturition. Concurrently, plasma P4 concentrations in non-reproductively active adult females remain basal (1 - 2 ng ml-1) throughout the year. There is good circumstantial evidence for a multiennial reproductive cycle in females. Parturition occurs late in the active season, presumably leaving little time for females to store sufficient fat reserves to become vitellogenic in the following spring: reproductive opportunities are effectively missed in at least one year following a reproductive effort. Observed reproductive behaviours, including agonistic male - male interactions, mating, and parturition, are documented. An investigation of gonadal steroid biosynthetic pathways in this viviparous squamate is presented. This compares variation in the relative contributions of the delta-4 and delta-5 steroidogenic pathways according to sex and reproductive condition. The delta-4 pathway predominates in both sexes, aligning this species phylogenetically with other reptiles. However, there are clear differences between sexes and with changing reproductive condition in the patterns of production of pathway intermediates and end-products. Additionally, detection of a possibly novel polar steroid as a major end-product of steroid biosynthesis in both sexes is reported. Peripheral (extragonadal) metabolism of T and E2 in a number of reproductively relevant steroid target tissues is compared at times of year chosen to represent three clearly distinctive reproductive conditions in each sex. There are differences both between sexes, between tissue types and with changing reproductive condition in the relative proportions of steroid conjugates and non-conjugated derivatives produced. Biosynthetic pathway activity and peripheral steroid metabolism both appear to be plastic in response to changing reproductive condition in Tiliqua nigrolutea. With a comprehensive database of information about the reproductive endocrinology and physiology of Tiliqua nigrolutea, this species is now available as a model to further examine selected aspects of the steroid hormone control of reproductive physiology and behaviour in a cool temperate, viviparous reptile.

abstract: Until the second half of the 20th century, publications on breathing techniques for woodwinds have been scarce and often failed to adequately address this aspect of performance and pedagogy. It is through various sensory experiences and because of recent technological advances that academics recognize a gap in the existing literature and have since included studies using various methods, as well as modern technical devices and experiments into the woodwind literature and teaching. These studies have proven to be of great importance to confirm ideas and hypotheses on the matter. The aim of this project is to collect woodwind journal publications into a meta-analysis, focusing specifically on the breathing techniques for woodwind instruments and provide a comprehensive annotated bibliography on the topic and its application. The project is limited to journal articles on breathing techniques applied for woodwinds only, and will not review literature discussing breathing from other perspectives or in a broader sense. Major findings show that misconceptions and contradictions on the subject still exist. At the same time, they also highlight unique approaches used to help the learner overcome general and specific challenges while mastering the art of breathing. The project highlights areas where future research on breathing would be encouraged and should be complemented by measured data. Such studies might include a woodwind specific examination of the relationship between the tongue and the soft palate, or analysis of how tension in the torso muscles influences the movement of the diaphragm, or how rhythmical breathing affects breath control and capacity, and finally a discussion on how larynx influences the air stream.
Dissertation/Thesis
Doctoral Dissertation Music 2019