An actuated larynx phantom for pre-clinical evaluation of droplet-based reflex-stimulating laryngoscopes

The laryngeal adductor reflex (LAR) is an important protective function of the larynx to prevent aspiration and potentially fatal aspiration pneumonia by rapidly closing the glottis. Recently, a novel method for targeted stimulation and evaluation of the LAR has been proposed to enable non-invasive and reproducible LAR performance grading and to extend the understanding of this reflexive mechanism. The method relies on the laryngoscopically controlled application of accelerated water droplets in association with a high-speed camera system for LAR stimulation site and reflex onset latency identification. Prototype laryngoscopes destined for this method require validation prior to extensive clinical trials. Furthermore, demonstrations using a realistic phantom could increase patient compliance in future clinical settings. For these purposes, a model of the human larynx including vocal fold actuation for LAR simulation was developed in this work. The combination of image processing based on a custom algorithm and individual motorization of each vocal fold enables spatio-temporal droplet impact detection and controlled vocal fold adduction. To simulate different LAR pathologies, the current implementation allows to individually adjust the reflex onset latency of the ipsi- and contralateral vocal fold with respect to the automatically detected impact location of the droplet as well as the maximum adduction angle of each vocal fold. An experimental study of the temporal offset between desired and observed LAR onset latency due to image processing was performed for three average droplet masses based on highspeed recordings of the phantom. Median offsets of 100, 120 and 128 ms were found (n=16). This offset most likely has a multifactorial cause (image processing delay, inertia of the mechanical components, droplet motion). The observed offset increased with increasing droplet mass, as fluid oscillations after impact may have been detected as motion. In future work, alternative methods for droplet impact detection could be explored and the observed offset could be used for compensation of this undesirable delay

Analysis of a soft bio-Inspired active actuation model for the design of artificial vocal folds

Phonation results from the passively induced oscillation of the vocal folds in the larynx, creating sound waves that are then articulated by the mouth and nose. Patients undergoing laryngectomy have their vocal folds removed and thus must rely on alternative sources of achieving the desired vibration of artificial vocal folds. Existing solutions, such as voice prostheses and the Electrolarynx, are limited by producing sufficient voice quality, for instance. In this paper, we present a mathematical analysis of a physical model of an active vocal fold prosthesis. The inverse dynamical equation of the system will help to understand whether specific types of soft actuators can produce the required force to generate natural phonations. Hence, this is referred to as the active actuation model. We present the analysis to replicate the vowels /a/, /e/, /i/, and /u/ and voice qualities of vocal fry, modal, falsetto, breathy, pressed, and whispery. These characteristics would be required as a first step to design an artificial vocal folds system. Inverse dynamics is used to identify the required forces to change the glottis area and frequencies to achieve sufficient oscillation of artificial vocal folds. Two types of ionic polymer-metal composite (IPMC) actuators are used to assess their ability to produce these forces and the corresponding activation voltages required. The results of our proposed analysis will enable research into the effects of natural phonation and, further, provide the foundational work for the creation of advanced larynx prostheses

Soft-bodied adaptive multimodal locomotion strategies in fluid-filled confined spaces

Soft-bodied locomotion in fluid-filled confined spaces is critical for future wireless medical robots operating inside vessels, tubes, channels, and cavities of the human body, which are filled with stagnant or flowing biological fluids. However, the active soft-bodied locomotion is challenging to achieve when the robot size is comparable with the cross-sectional dimension of these confined spaces. Here, we propose various control and performance enhancement strategies to let the sheet-shaped soft millirobots achieve multimodal locomotion, including rolling, undulatory crawling, undulatory swimming, and helical surface crawling depending on different fluid-filled confined environments. With these locomotion modes, the sheet-shaped soft robot can navigate through straight or bent gaps with varying sizes, tortuous channels, and tubes with a flowing fluid inside. Such soft robot design along with its control and performance enhancement strategies are promising to be applied in future wireless soft medical robots inside various fluid-filled tight regions of the human body

Uncanny Objects: The Art of Moving and Looking Human

Automata ( self-moving machines) and reborn dolls (hyperrealistic baby dolls) individually conjure up questions of dynamic and aesthetic realism--external components of the human form as realistically represented or reproduced. as simulacra of humans in movement and appearance, they serve as sites of the uncanny exemplifying the idea in which as varying forms of the cyborg imbue them with troubling yet fantastical qualities that raises questions about our own humanness. My first essay, “Automaton: Movement and Artificial/Mechanical Life” directly addresses the characteristics that define humanness, principally the Rene Descartes mind-body dichotomy, by tracing the evolution of mechanical life, predicated as much on movement as consciousness, via the construction of automata. “Dis/Playing with Dolls: Stigmatization and the Performance of Reborn Dolls” takes the discussion a step further and examines people’s reactions when objects that look human are treated like human. I compare observable behaviors of dolls owners via social mediums like videos posted on YouTube, message boards, blogs, and news sources with responses by observers of this type of doll play, and superimposing a theory of play over this interaction. Whether or not automata and reborn dolls are socially accepted as signifiers of humanness, they already exist within our social space and reality. It is the recognition and acknowledgement of their presences in our everyday life and their agency that puts them squarely in the discourse of life

Numerical Investigation of Subglottal Stenosis Effects on Human Voice Production

This dissertation aimed to advance knowledge of how subglottal stenosis impacts voice production physiology. An in-house fluid-structure-acoustic interaction approach based on the hydrodynamic/acoustic splitting technique was employed. This technique was rigorously verified for simulating phonation by matching the acoustic behavior to a compressible flow solver for phonation-relevant geometries. Simulations of an idealized 2D vocal tract model demonstrated the effects of supraglottal acoustic resonance on vocal fold kinematics and glottal flow waveform. Results showed that the acoustic coupling between higher harmonics and formats generated pressure oscillations, modifying vocal fold dynamics and glottal flow rate. A major novelty was the incorporation and systematic parametric study of subglottal stenosis effects on voice production in an idealized 3D laryngeal model for the first time. Variation of subglottal stenosis severity revealed changes in vocal fold motion for severities higher than 90%, and flow rate and acoustics for severities higher than 75%. Detailed analysis revealed relative flow resistance and the ratio between glottal and stenosis minimum areas as primary factors determining the degree of influence. This provided new insights relating stenosis severity to physical changes in voice production consistent with clinical intervention guidelines. Highly detailed subject-specific realistic laryngeal and vocal tract geometries were reconstructed from high-resolution imaging to enable developing a coupled flow-acoustics-solid interaction model. Self-sustained vocal fold oscillations and glottal flow rates matching human phonation validated this highfidelity model’s capabilities. Parametric stenosis studies provided confirmation using real geometries and additional insights into underlying physical mechanisms. In summary, this dissertation research verified numerical methods, revealed acoustic resonance effects, systematically quantified stenosis severity thresholds, and elucidated mechanisms relating observations to area ratio and pressure drops. Outcomes significantly advance fundamental knowledge of simulating normal and pathological voice production. This work provides a strong foundation for future translational research on modeling other voice disorders, supporting surgical planning, and guiding interventions

Resonant Detection of Nano to Microscopic Objects Using Whispering Gallery Modes

A micron sized glass sphere is able to confine light to its interior volume. The trapped light describes an orbital trajectory circumnavigating just below the microsphere surface. Whenever the light ray tries to escape it is sent back on its circular path by total internal reflection. The light orbit closes in on itself several thousand times and thus creates an optical resonance. The unprecedented narrow linewidth of such a microsphere resonance (Q factors of up to 3 x 10 ) allows precise measurement of its frequency. Dielectric microspheres of very high Q are thus the ideal choice for a resonant molecular sensor. Although the resonance is stealth, an evanescent field extends from the microsphere surface the distance of a wavelength into the surrounding medium. This thesis demonstrates how label-free molecules binding to the microsphere surface perturb the optical resonance by interaction with this evanescent field. The effect is demonstrated by surface adsorption of a protein (serum albumin). The general use as a biosensor is shown by specific detection of streptavidin binding to biotin. A first order perturbation theory describing the linear response of the sensor is presented. Molecular perturbation leads to a wavelength shift that can be measured with such high precision that single molecule detection seems theoretically possible. The experimental approach is extended to the multiplexed measurement of D N A hybridization using two microsphere resonators. This differential measurement allows the detection of a single nucleotide mismatch with a high signal to noise ratio. The effect of larger Mie particles such as bacteria and polystytrene nanospheres perturbing the cavity resonance is examined experimentally and theoretically. For such larger objects it is necessary to include the decay length of the evanescent field in the theoretical analysis. The Q spoiling which occurs for such large Mie particles is described by an analytic formula. Furthermore, a pairing effect is observed for polystyrene nanospheres with diameters of ~ a quarter wavelength polarized in the evanescent field of the microsphere resonance. A novel mechanism might be involved since the coupling cannot be explained by simple dipole-dipole interactions

Nature-inspired soft robotics: On articial cilia and magnetic locomotion

Inspired by micro-organisms in nature, people imagined using micro-scale soft robots to work inside the human body for therapeutic drug delivery, minimally invasive surgery, or diagnostic biochemical sensing. To create these robots is challenging due to their small size, viscosity environment, and soft constituting materials. In addition, the mechanisms of operation are quite different from the conventional rigid macro-scale robots that we are familiar with. In this PhD project, we focused on the computational analysis and design of micro-scale soft robots. Working closely with experimental groups, we studied artificial cilia and micro-swimmers that can realize particle manipulation, fluid transport, fluid mixing, or magnetic locomotion. Various cilia systems are considered, including soft inflatable cilia which could be controlled individually and programmable magnetic cilia featuring phase shifts and collective metachronal patterns. We also analyze micro-swimmers that are soft and adaptive in confined spaces. Driven by different external magnetic fields, the swimmer's motion can be changed between undulation crawling, undulation swimming, and helical crawling. By using computational modeling, we analyze the transport mechanisms of the soft robots and study the effect of different parameters to provide guidelines for the design of the robots in specific applications. By studying the physical mechanisms of micro-organisms in nature, we are not only able to understand more clearly their functional behaviour, it also opens the possibility of biomimetic design of soft robotic cilia and micro-swimmers

Professional English for biomedical engineering students

Навчальний посібник забезпечує аудиторну та самостійну роботу студентів третього курсу факультету біомедичної інженерії. Видання складається з восьми розділів (Units), які охоплюють професійно орієнтовані теми (Topics): “Introduction to biomedical engineering”, “Robotics in biomedical and healthcare engineering”, “Tissue engineering”, “Medical Imaging”, “Nanotechnology in biomedical engineering”, “Rehabilitation engineering”, “Biomaterials”, “Genetic engineering”. Розроблені вправи спрямовані на забезпечення знань, розвиток і удосконалення навичок і вмінь у читанні, говорнні, аудіюванні, письмі та перекладі, а також покращення лексичних та граматичних знань, навичок і умінь студентів. Завданням посібника є сприяння розширенню професійного тезаурусу студентів та підвищення мотивації студентів до автономного навчання

Utopia/Dystopia, Race, Gender, and New Forms of Humanism in Women's Science Fiction

This thesis aims to uncover new forms of humanism grounded in a critique of systems that produce and reify race and gender by staging a conversation between six contemporary works of science fiction (SF) written by women from Italy, France, Spain, and the UK, and five acclaimed theorists in the fields of gender, queer, postcolonial, humanist, and cultural studies: Judith Butler, Rosi Braidotti, Gayatri Spivak, Paul Gilroy, and Jack Halberstam. As outlined in the second chapter, I focus, in particular, on Butler’s conception of subjects who ‘become’ through affective encounters, Braidotti’s critical posthumanism, Spivak and Gilroy’s respective notions of ‘planetarity,’ and Halberstam’s theory of a ‘queer art of failure.’ In doing so, this thesis asserts the complementarity of academic and science fictional enquiries into what I view as examples of new forms of humanism that arise from historicised interrogations of systems of race and gender. The first chapter introduces the way in which SF appeals to women writers who embrace the genre’s political energy and its anti-racist, anti-sexist, and humanistic potential by tracing a genealogy of European women’s SF from the seventeenth century to the present day. The second half of the thesis reads examples of politically charged SF from my corpus alongside the critical theory outlined in the second chapter, in order to demonstrate how SF engages with new forms of humanism through a critique and reformulation of issues of race and gender. I follow this analysis with an exploration of the way in which SF’s unique spatial attributes can probe the borders of the planetary humanisms or ‘planetarity’ proposed by Gilroy and Spivak. I finally assess, by way of a conclusion, the extent to which SF can reassemble and amplify the achievements of these new forms of anti-racist and anti-sexist humanism