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Self-sustained oscillations of the vocal folds (VFs) during phonation are the result of the energy exchange between the airflow and VF tissue. Understanding this mechanism requires accurate investigation of the aerodynamic pressures acting on the VF surface during oscillation. A self-oscillating silicone VF model was used in a hemilaryngeal flow facility to measure the time-varying pressure distribution along the inferior-superior thickness of the VF and at four discrete locations in the anterior-posterior direction. It was found that the intraglottal pressures during the opening and closing phases of the glottis are highly dependent on three-dimensional and unsteady flow behaviors. The measured aerodynamic pressures and estimates of the medial surface velocity were used to compute the intraglottal energy transfer from the airflow to the VFs. The energy was greatest at the anterior-posterior midline and decreased significantly toward the anterior/posterior endpoints. The findings provide insight into the dynamics of the VF oscillation and potential causes of some VF disorders.
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http://dx.doi.org/10.1121/10.0005882 | DOI Listing |
Comput Methods Programs Biomed
September 2025
School of Biological Sciences and Medical Engineering, Southeast University, Nanjing, Jiangsu, China. Electronic address:
Background And Objective: The quantitative knowledge of the influence of the small airway disease on the functional changes in chronic obstructive pulmonary disease (COPD) patients has been severely limited.
Methods: This study presents an innovative patient-specific computational framework that integrates CT and OCT imaging data with multiscale computational fluid dynamics (CFD) analysis. A three-dimensional tracheobronchial tree is reconstructed from CT scans of a mild COPD patient, spanning from the central airway to the 4th generation bronchial bifurcations.
Sci Adv
September 2025
School of Aeronautics, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, China.
Flying vertebrates use specialized wingbeat kinematics in hovering, takeoff, and landing, featuring ventrally anterior downstrokes and aerodynamically inactive upstrokes to enhance aerodynamic characteristics at low airspeeds. Rarely implemented in robotics, this inspired RoboFalcon2.0, a flapping-wing robot with reconfigurable mechanisms performing bioinspired flap-sweep-fold (FSF) motion for controlled bird-style takeoff.
View Article and Find Full Text PDFJ Asthma Allergy
August 2025
Faculty of Medicine and Health Technology, Tampere Center for Child, Adolescent and Maternal Health Research, Tampere University, Tampere, Finland.
Introduction: Discoordination between inhalation and pressurized metered-dose inhaler (pMDI) actuation when delivering inhaled corticosteroids (ICS) is a common technique error that can lead to worsened treatment outcomes. Valved holding chambers (VHCs) are thought to improve the delivered dose if inhalation is delayed, but this effect has not been sufficiently quantified.
Methods: The aerodynamic particle size distribution of fluticasone propionate (FP) and ciclesonide (CIC) was studied under three conditions: inhalation initiated before actuation without a VHC, inhalation started at actuation without a VHC, and inhalation started at actuation with a VHC.
IEEE Trans Audio Speech Lang Process (2025)
April 2025
Department of Electronic Engineering and with the Advanced Center for Electrical and Electronic Engineering, Universidad Técnica Federico Santa María, Valparaíso, Chile.
This study presents a novel application of a Probabilistic Bayesian Neural Network (PBNN) for estimating vocal function variables and enhancing non-invasive ambulatory voice monitoring by addressing aleatoric and epistemic uncertainties in regression tasks. The proposed PBNN allows for estimating key physiological parameters including subglottal pressure, vocal fold contact pressure, thyroarytenoid, and cricothyroid muscle activations, from seven aerodynamic and acoustic features. The PBNN is trained on the Triangular Body-Cover Model (TBCM) of the vocal folds to produce a non-linear inverse mapping between its inputs and outputs.
View Article and Find Full Text PDFJ Biomech Eng
September 2025
Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Department of Pediatrics, University of Cincinnati, Cincinnati, OH, United States, Department of Radiology and Medical Imaging, Cincinnati Children's Hospital Medical Center, Cincinnati, OH,
Obstructive sleep apnea (OSA) is characterized by recurrent upper airway collapse during sleep, resulting from interactions between aerodynamic forces, neuromuscular activation, and tissue properties. This study introduces a novel methodology for analyzing airway wall dynamics by incorporating acceleration-based metrics into computational fluid dynamics (CFD) simulations to better understand the pathophysiology of airway collapse in OSA. A patient with OSA underwent magnetic resonance imaging (MRI) to capture airway anatomy and motion under sleep-like sedation.
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