A perceptually evaluated signal model:Collisions between a vibrating object and an obstacle

The collision interaction mechanism between a vibrating string and a non-resonant obstacle is at the heart of many musical instruments. This paper focuses on the identification of perceptually salient auditory features related to this phenomenon. The objective is to design a signal-based synthesis process, with an eye towards developing intuitive control strategies. To this end, a database of synthesized sounds is assembled through physics-based emulation of a string/obstacle collision, in order to characterize the effect of collisions on time-frequency content. The investigation of this database reveals characteristic time-frequency patterns related to the position of the obstacle during the interaction. In particular, a frequency shift of certain modes is apparent for strong interactions, which, alongside the generation of new frequency components, leads to increased perceived roughness and inharmonicity. These observations enable the design of a real-time compatible signal-based sound synthesis process, with a mapping of synthesis parameters linked to the perceived location of the obstacle. The accuracy of the signal model with respect to the physical model sound output and recorded sounds was evaluated through listening tests: time-frequency patterns reproduced by the signal model enabled listeners to precisely recognize the transverse location of the obstacle

On the influence of non-linear phenomena on perceived interactions in percussive instruments

International audienceIn this paper, we investigate the hypothesis that perceived impact strength is strongly influenced by the non-linear behavior produced by large deformations in percussive instruments. A sound corpus is first generated from a physical model that simulates non-linear vibrations of a thin plate. The e↵ect of non-linear phenomena on the perceived strength is further quantified through a listening test. The aim of this study is to improve the expressive potential of synthesizers of percussive sounds through the development of signal transformation models. Future work will focus on the modeling of sound morphologies that correspond to non-linear behavior and the development of a transparent control strategy

The Safe Use of a PTEN Inhibitor for the Activation of Dormant Mouse Primordial Follicles and Generation of Fertilizable Eggs

Primordial ovarian follicles, which are often present in the ovaries of premature ovarian failure (POF) patients or are cryopreserved from the ovaries of young cancer patients who are undergoing gonadotoxic anticancer therapies, cannot be used to generate mature oocytes for in vitro fertilization (IVF). There has been very little success in triggering growth of primordial follicles to obtain fertilizable oocytes due to the poor understanding of the biology of primordial follicle activation.We have recently reported that PTEN (phosphatase and tensin homolog deleted on chromosome ten) prevents primordial follicle activation in mice, and deletion of Pten from the oocytes of primordial follicles leads to follicular activation. Consequently, the PTEN inhibitor has been successfully used in vitro to activate primordial follicles in both mouse and human ovaries. These results suggest that PTEN inhibitors could be used in ovarian culture medium to trigger the activation of primordial follicle. To study the safety and efficacy of the use of such inhibitors, we activated primordial follicles from neonatal mouse ovaries by transient treatment with a PTEN inhibitor bpV(HOpic). These ovaries were then transplanted under the kidney capsules of recipient mice to generate mature oocytes. The mature oocytes were fertilized in vitro and progeny mice were obtained after embryo transfer.Long-term monitoring up to the second generation of progeny mice showed that the mice were reproductively active and were free from any overt signs or symptoms of chronic illnesses. Our results indicate that the use of PTEN inhibitors could be a safe and effective way of generating mature human oocytes for use in novel IVF techniques

Immature Cryopreserved Ovary Restores Puberty and Fertility in Mice without Alteration of Epigenetic Marks

BACKGROUND: Progress in oncology could improve survival rate in children, but would probably lead to impaired fertility and puberty. In pre-pubertal girls, the only therapeutic option is the cryopreservation of one ovary. Three births have been reported after reimplantation of cryopreserved mature ovary. Conversely, reimplantation of ovary preserved before puberty (defined as immature ovary) has never been performed in humans. METHODOLOGY/PRINCIPAL FINDINGS: In order to analyze ovarian function, we performed transplantation using fresh or cryopreserved immature grafts in pre-pubertal or adult mice. Puberty as well as cyclic hormonal activity was restored. All follicle populations were present although a significant reduction in follicle density was observed with or without cryopreservation. Although fertility was restored, the graft is of limited life span. Because ex vivo ovary manipulation and cryopreservation procedure, the status of genomic imprinting was investigated. Methylation status of the H19 and Lit1 Imprinting Control Regions in kidney, muscle and tongue of offsprings from grafted mice does not show significant alteration when compared to those of unoperated mice. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that immature ovarian grafting can restore spontaneous puberty and fertility. However, these data suggest that follicle depletion leads to premature ovarian failure. This study addresses the very important epigenetics issue, and provides valuable information to the study of ovarian transplantation suggesting that these procedures do not perturb normal epigenetics marks. These results are highly relevant to the reimplantation question of immature cortex in women

Des non-linéarités physiques à la perception sonore

The work carried out in this thesis aims to design a model for environmental sound synthesis, taking into account the nonlinear phenomena involved in the physical modeling of sound sources. We seek to propose a simplified model of the sound signal that aligns with human perception. The methodology followed is as follows: -Generate a corpus through the physical simulation of sound sources, where the nonlinear behavior is representative of previously classified sound percepts; -Determine the corresponding sound morphologies through the analysis of non-stationary signals from the corpus; -Design a coherent model of the sound signal aligned with perception; -Evaluate and calibrate the transcription of the phenomenon in the signal model using listening tests. After specifying the context and the stakes of this subject, we present the generation of a sound corpus and the determinations of associated sound morphologies for two characteristic cases of nonlinear phenomena: the perturbation of vibrations in a stiff string by a rigid obstacle and the vibrations of a thin plate for large amplitudes of elastic vibrations. We have deduced that a common aspect in these two cases is the transfer of energy to high frequencies. We then propose a signal model for energy transfers between modes for the synthesis of sounds corresponding to nonlinear phenomena, and we evaluate the transcription of the phenomena by the signal model using listening tests.Le travail effectué dans cette thèse a pour objectif de concevoir un modèle pour la synthèse de son d'environnement prenant en compte les phénomènes non-linéaires intervenant dans la modélisation physique des sources sonores. Nous cherchons à proposer un modèle simplifié du signal sonore en adéquation avec la perception humaine. La méthodologie suivie consiste à : - générer un corpus par la simulation physique de sources sonores dont le comportement non-linéaire est représentatif de percepts sonores préalablement classifiés ; - déterminer les morphologies sonores correspondantes à partir de l'analyse des signaux non-stationnaires du corpus ; - concevoir un modèle de signal simplifié cohérent avec la perception ;- évaluer et calibrer la transcription du phénomène dans le modèle de signal à l'aide de tests d'écoute. Après avoir précisé le contexte et les enjeux de ce sujet, nous présentons la génération d'un corpus de sons et les déterminations des morphologies sonores associées pour deux cas de figures caractéristiques des phénomènes non-linéaires dans la production des sons solidiens : la perturbation des vibrations d'une corde raide par un obstacle rigide et les vibrations d'une plaque mince pour de grandes amplitudes de vibrations élastiques. Nous en avons déduit qu'un aspect commun à ces deux cas de figure était les transferts d'énergie vers les hautes fréquences. Nous proposons ensuite un modèle de signal pour les transferts d'énergie entre les modes pour la synthèse de sons correspondant à des phénomènes non-linéaires et nous évaluons la transcription des phénomènes par le modèle de signal à l’aide de tests d'écoute

Modélisation des Phénomènes Non-linéaires pour le Réalisme de la Synthèse de Sons Percussifs

International audienc

From physical nonlinearity to auditory perception

Le travail effectué dans cette thèse a pour objectif de concevoir un modèle pour la synthèse de son d'environnement prenant en compte les phénomènes non-linéaires intervenant dans la modélisation physique des sources sonores. Nous cherchons à proposer un modèle simplifié du signal sonore en adéquation avec la perception humaine. La méthodologie suivie consiste à : - générer un corpus par la simulation physique de sources sonores dont le comportement non-linéaire est représentatif de percepts sonores préalablement classifiés ; - déterminer les morphologies sonores correspondantes à partir de l'analyse des signaux non-stationnaires du corpus ; - concevoir un modèle de signal simplifié cohérent avec la perception ;- évaluer et calibrer la transcription du phénomène dans le modèle de signal à l'aide de tests d'écoute. Après avoir précisé le contexte et les enjeux de ce sujet, nous présentons la génération d'un corpus de sons et les déterminations des morphologies sonores associées pour deux cas de figures caractéristiques des phénomènes non-linéaires dans la production des sons solidiens : la perturbation des vibrations d'une corde raide par un obstacle rigide et les vibrations d'une plaque mince pour de grandes amplitudes de vibrations élastiques. Nous en avons déduit qu'un aspect commun à ces deux cas de figure était les transferts d'énergie vers les hautes fréquences.Nous proposons ensuite un modèle de signal pour les transferts d'énergie entre les modes pour la synthèse de sons correspondant à des phénomènes non-linéaires et nous évaluons la transcription des phénomènes par le modèle de signal à l’aide de tests d'écouteThe objective of the research work presented in this thesis is to design a model for environmental sound synthesis that takes into account the non-linear phenomena involved in the physical modelling of sound sources. We aim to propose a simplified model of the sound signal consistent with human perception. The methodology followed consists of : - generating a corpus by the physical simulation of sound sources whose non-linear behaviour is representative of previously classified sound percepts;- determining the corresponding sound morphologies from the analysis of the non-stationary signals of the corpus; - design a simplified signal model consistent with the perception; - evaluate and calibrate the transcription of the phenomenon in the signal model using listening tests. After having specified the context and the challenges of this subject, we present the generation of a corpus of sounds and the determinations of the associated sound morphologies for two typical cases of non-linear phenomena in the production of solid sounds: the perturbation of the vibrations of a stiff string by a rigid obstacle and the vibrations of a thin plate for large amplitudes of elastic vibrations. We deduce that one aspect common to these two cases is the energy transfers towards high frequency components.We then propose a signal model for the energy transfers between frequency components for the synthesis of sounds corresponding to non-linear phenomena and we evaluate the transcription of the phenomena by the signal model using listening test

Des non-linéarités physiques à la perception sonore

The work carried out in this thesis aims to design a model for environmental sound synthesis, taking into account the nonlinear phenomena involved in the physical modeling of sound sources. We seek to propose a simplified model of the sound signal that aligns with human perception. The methodology followed is as follows: -Generate a corpus through the physical simulation of sound sources, where the nonlinear behavior is representative of previously classified sound percepts; -Determine the corresponding sound morphologies through the analysis of non-stationary signals from the corpus; -Design a coherent model of the sound signal aligned with perception; -Evaluate and calibrate the transcription of the phenomenon in the signal model using listening tests. After specifying the context and the stakes of this subject, we present the generation of a sound corpus and the determinations of associated sound morphologies for two characteristic cases of nonlinear phenomena: the perturbation of vibrations in a stiff string by a rigid obstacle and the vibrations of a thin plate for large amplitudes of elastic vibrations. We have deduced that a common aspect in these two cases is the transfer of energy to high frequencies. We then propose a signal model for energy transfers between modes for the synthesis of sounds corresponding to nonlinear phenomena, and we evaluate the transcription of the phenomena by the signal model using listening tests.Le travail effectué dans cette thèse a pour objectif de concevoir un modèle pour la synthèse de son d'environnement prenant en compte les phénomènes non-linéaires intervenant dans la modélisation physique des sources sonores. Nous cherchons à proposer un modèle simplifié du signal sonore en adéquation avec la perception humaine. La méthodologie suivie consiste à : - générer un corpus par la simulation physique de sources sonores dont le comportement non-linéaire est représentatif de percepts sonores préalablement classifiés ; - déterminer les morphologies sonores correspondantes à partir de l'analyse des signaux non-stationnaires du corpus ; - concevoir un modèle de signal simplifié cohérent avec la perception ;- évaluer et calibrer la transcription du phénomène dans le modèle de signal à l'aide de tests d'écoute. Après avoir précisé le contexte et les enjeux de ce sujet, nous présentons la génération d'un corpus de sons et les déterminations des morphologies sonores associées pour deux cas de figures caractéristiques des phénomènes non-linéaires dans la production des sons solidiens : la perturbation des vibrations d'une corde raide par un obstacle rigide et les vibrations d'une plaque mince pour de grandes amplitudes de vibrations élastiques. Nous en avons déduit qu'un aspect commun à ces deux cas de figure était les transferts d'énergie vers les hautes fréquences. Nous proposons ensuite un modèle de signal pour les transferts d'énergie entre les modes pour la synthèse de sons correspondant à des phénomènes non-linéaires et nous évaluons la transcription des phénomènes par le modèle de signal à l’aide de tests d'écoute