Glottis: The glottis is defined as the opening between the vocal folds Ladefoged, Peter. 2006.Vocal folds: The vocal folds, also known commonly as vocal cords or voice reeds, are composed of twin infoldings of mucous membrane stretched horizontally, from back to front, across the larynx. They vibrate, modulating the flow of air being expelled from the lungs during phonation.Janwillem van den Berg: Janwillem van den Berg (20 November 1920 in Akkrum – 18 October 1985 in Akkrum) was a Dutch speech scientist and medical physicist who played a major role in establishing the myoelastic-aerodynamic theoryTitze, I. R.Hyoepiglottic ligament: The hyoepiglottic ligament is an elastic band connecting the anterior surface of the epiglottis to the upper border of the body of the hyoid bone. It is clinically important in performing direct laryngoscopy with a Macintosh laryngoscope blade; the blade tip is placed in the vallecula and moved anteriorly, which causes the hyoepiglottic ligament to pull the epiglottis anteriorly as well and thus expose the glottis.Infraglottic cavity: The infraglottic cavity is the portion of the larynx below the laryngeal ventricles and the rima glottidis.Mallampati scoreSubglottic stenosisHistory of tracheal intubation: Tracheal intubation (usually simply referred to as intubation), an invasive medical procedure, is the placement of a flexible plastic catheter into the trachea. For millennia, tracheotomy was considered the most reliable (and most risky) method of tracheal intubation.Pharynx: The pharynx (plural: pharynges) is an organ found in vertebrates and invertebrates, though the structure is not universally the same across the species. In humans the pharynx is part of the digestive system and also of the conducting zone of the respiratory system.Hydrogen darkening: Hydrogen darkening is a physical degradation of the optical properties of glass. Free hydrogen atoms are able to bind to the SiO2 silica glass compound forming hydroxyl (OH) - a chemical compound that interferes with the passage of light through the glass.Voice changer: The term voice changer (also known as voice enhancer) refers to a system of altering a person's voice to either make them sound like someone else or to disguise their voice.Dysprosody: Dysprosody, which may manifest as pseudo-foreign accent syndrome, refers to a disorder in which one or more of the prosodic functions are either compromised or eliminated completely.Posterior cricoarytenoid muscle: The posterior cricoarytenoid muscles are extremely small, paired muscles that extend from the posterior cricoid cartilage to the arytenoid cartilages in the larynx.List of voice disorders: Voice disordersTitze, I.R.Transpulmonary pressure: Transpulmonary pressure is the difference between the alveolar pressure and the intrapleural pressure in the lungs. During human ventilation, air flows because of pressure gradients.Beta encoder: A beta encoder is an analog to digital conversion (A/D) system in which a real number in the unit interval is represented by a finite representation of a sequence in base beta, with beta being a real number between 1 and 2. Beta encoders are an alternative to traditional approaches to pulse code modulation.Journal of Rheology: Journal of Rheology is a peer-reviewed scientific journal publishing original (primary) research on all aspects of rheology, the study of those properties of materials which determine their response to mechanical force. It is published bimonthly by the Society of Rheology through the American Institute of Physics.