To understand the effect of the sound field on sonochemical luminescence, the exact sound pressure must be determined in each field. In this study it was determined by the Shlieren method, which measures the sound pressure without mixing the sound fields. We compared the efficiency of the sonochemical luminescence in ...

Head extension with protruded tongue is the position for videolaryngoscopy and simultaneous glottographic recordings including photoglottographic signals. This study investigated the effect of head extension and tongue protrusion on the measures of fundamental frequency, frequency perturbation (jitter), and amplitude perturbation (shimmer). Acoustic signals recorded during sustained vowels were obtained from ...

We investigated the laryngeal closure pressure during sustained phonation in five healthy adult men with no pathological lesions in the glottis using a round pressure transducer with a diameter of 10 mm and a thickness of 1 mm. The transducer was placed between the vocal processes through the mouth. Subjects ...

Ambient sound pressure levels (SPLs) created with intense blasts were compared with SPLs recorded in the abdomen of euthanized sheep. Hydrophones were placed in the abdominal cavity at locations referred to as proximal, medial, and distal with respect to a shock tube that created 169-dB peak SPL (pSPL). No differences ...

The effect of massage on voice fundamental frequency (F(0)) and sound pressure level (SPL) was investigated. Subjects were recorded while reading a 3-min passage of prose text. Then, a 30-min session of massage was administered by a trained naprapathy therapist. Sixteen subjects were given the massage, while 15 controls rested, ...

Twenty-eight high trait hostility male volunteers played a "cooperative" computer game 4.5 hours after an amino acid drink enhanced with, or depleted of, tryptophan. Each trial involved steering a tank through minefields following directions from an unknown "partner." Failure was experienced when the tank hit a mine or when time ...

OBJECTIVE: Transient sound disturbances are common but neglected symptoms in retraction type middle ear disease (R-MED). The aim of this study was to explore and describe their character, their individual consequences, and their role in the development of tympanic membrane retractions. METHODS: Fifty-three subjects with manifest retractions and experiences of ...

The pressure in the alveoli of the lungs, created by the elastic recoil of the lungs and respiratory muscle activity, is referred to as alveolar pressure (Pa). The extent to which tracheal pressure (Pt) approximates Pa depends on the resistance to airflow offered by structures above and below the point ...

The study aimed to determine the relationship between the physical magnitude and the subjective perception of applied pressure, and to determine discomfort and pain thresholds. Free modulus magnitude estimation of the subjective pressure level was made on three points: on the finger, the palm and the thenar area. The pressure ...

The cohesion-tension theory of the ascent of sap in plants is fundamental to the understanding of water movement in plants. According to the theory, water is pulled upwards by high tensions (low negative pressures) created in the xylem vessels and tracheids of higher plants by the evaporation of water vapour ...

OBJECTIVES: To quantify neurological dysfunction in workers exposed to hand-transmitted vibration using alternative neurological tests. To relate the neurological findings to the results of vascular tests and the symptoms reported by subjects with vibration-induced white finger. METHODS: Thermal thresholds (for perception of heat and cold), vibrotactile thresholds (for perception of ...

Very low frequencies interfere in the intact cochlea with higher frequencies and suppress these depending on the vibration phase of the low-frequency sound. Physiological functions of the body, mediated, for example, by the eardrum or perilymph coupling with the cerebrospinal fluid, cause a low-frequency pressure modulation of the perilymph, which ...

The purpose of this study was to evaluate acoustic noise in echo planar imaging (EPI) at various magnetic resonance imaging (MRI) centers and to compare EPI acoustic noise with that in other fast pulse sequences. We measured A-weighted root-mean-square sound pressure levels and peak impulse sound pressure levels for EPI, ...

The quality of tracheoesophageal (TE) voice after laryngectomy is dependent on numerous factors. The relative contribution of specific variables is not well described. To evaluate the modulation of fundamental frequency (F0) pitch in TE speakers after total laryngectomy and voice restoration, we instructed 11 TE speakers to complete a series ...

Two mechanisms are said to be responsible for the expansion commonly produced by buccal shields: (1) unbalanced tongue pressure and (2) periosteal pull; that is, periosteal traction on the bone overlying the molar roots. The present study used 44 young albino rats to examine these two alternatives. Half the rats ...

This experiment was conducted to examine whether the vocal expression of anger correlated with cardiovascular reactivity within dyadic interactions. Participants selected three social issues on which they had a strong opinion and, with a confederate who opposed their views, debated these opinions in each of the three vocal styles. The ...

The effects of prolonged (5x45 minute) reading (vocal loading) on fundamental frequency (F0), sound pressure level (SPL), subglottal (intraroral) pressure (p), and two glottal flow waveform parameters (AC amplitude of glottal flow, f, and negative peak amplitude of differentiated flow (d) of normal female and male subjects (N = 80) ...

The pressures acting on the maxillary and mandibular posterior teeth from the tongue and cheeks were measured in 24 adults aged 22-29 years. In addition, the pressure in the palatal vault was recorded. The pressure at two maxillary (buccal and lingual) and two mandibular (buccal and lingual) measuring points, and ...

One hundred thirty human temporal bones that were sectioned in the vertical plane were examined to evaluate the relationship between the stapes footplate and the otolith organs. The shortest distance between the footplate and the utriculus was 0.58+/-0.10 mm in the posterior third of the oval window, 1.04+/-0.20 mm in ...

Voice source characteristics as derived from inverse filtering were analyzed in 6 country singers' speech and singing. Results showed that the closed quotient varied systematically with vocal loudness, and that glottal compliance (the ratio between transglottal AC volume displacement and subglottal pressure) decreased with increases in fundamental frequency but remained ...

This study investigated the physiological and psychological effects of music listening on depressed women in Taiwan. Through the use of a pretest-posttest, control group, experimental design, the heart rate, respiratory rate, blood pressure, and immediate mood states before and after a music/sound intervention were measured in 30 women. Quantitative data ...

OBJECTIVE: We have observed clinically that some speakers wearing a speech appliance for correction of velopharyngeal incompetence can blow with variable intensity without nasal air escape. This clinical finding suggests that tightness of velopharyngeal closure may be regulated in accordance with oral air pressure during blowing. The purposes of this ...

During each of four successive sessions (once per week), 21 university students attended 3-hr. lectures. During alternative weeks the fans of the room's ventilation system were either on or off. When operating, they generated an average sound pressure that varied continuously between 60 and 65 dB. The dominant frequency of ...

Pressure on the teeth from the labial soft tissues during the articulation of a given sentence was measured in 24 children, 8 to 14 years old, with normal incisor relationships. The points of measurement were labial in the midlines between the maxillary and mandibular central incisors and between the right ...

The purpose of the experiment was to explore relations between jaw and laryngeal functions. The general question was whether laryngeal adduction was affected by jaw opening or by jaw biting. Twelve untrained, vocally healthy male and female adults participated as subjects. Subjects produced repeated tokens of /uh/ in each of ...

Experiments using excised canine larynges were conducted to study the restoration of vocal efficiency in dehydrated larynges. Excised larynges were dehydrated with warm, dry air to the point that airflow through the approximated vocal folds would not entrain the folds to produce phonation. The dehydrated vocal folds were then bathed ...

OBJECTIVE/HYPOTHESIS: Most methods to measure phonation threshold pressure (PTP) are clinically impractical because they are invasive. This report concerns an airflow interruption system developed to allow noninvasive estimation of (PTP) at different levels of vocal intensity. An estimation of PTP was made for normal subjects with normal larynges and no ...

Five professional operatic baritone singers' voice-source characteristics were analyzed by means of inverse filtering of the flow signal as captured by a flow mask. The subjects sang a long sustained diminuendo, from loudest to softest, three times on the vowels [a:] and [ae:] at fundamental frequencies representing 25%, 50%, and ...

Human newborns appear to regulate sucking pressure when bottle feeding by employing, with similar precision, the same principle of control evidenced by adults in skilled behavior, such as reaching (Lee et al., 1998a). In particular, the present study of 12 full-term newborn infants indicated that the intraoral sucking pressures followed ...

Although continuous auscultation has been used during surgery as a monitor of cardiac function for many years, the effect of anesthetics on heart sounds has never been quantified. We determined the root mean squared amplitude and frequency characteristics (peak frequency, spectral edge, and power ratios) of the first (S1) and ...

Measurements of sound output as a function of blowing pressure are reported for a group of experienced trumpet players. The study identifies several common features, namely (1) a threshold blowing pressure approximately proportional to the frequency of the note being played, (2) an extended region in which the sound output ...

Twenty healthy adults, age range 20-55 years, participated in a study to assess the responses of the upper airway to sudden, unanticipated pressure venting during speech production. A computer was used to open or close a valve in a random fashion during one of two productions of the word 'hamper'. ...

According to experience in voice therapy and singing pedagogy, breathing habits can be used to modify phonation, although this relationship has never been experimentally demonstrated. In the present investigation we examine if lung volume affects phonation. Twenty-four untrained subjects phonated at different pitches and degrees of vocal loudness at different ...

The purpose of this study was to explore the possible use of the electroglottographic closed quotient (EGG CQ) as a noninvasive estimate of vocal fold impact stress (SI). Two excised canine larynges were used. Each larynx was mounted and vocal fold oscillation was induced using a humidified air source. Twenty-seven ...

The basics of pulsatile ejection dynamics are reviewed in order to clarify the relationships among left ventricular and aortic pressures, intra-left ventricular and aortic flow velocities, and cardiovascular sound. The principles of turbulent flow are examined using the Reynolds number concept, and the evidence for cause-and-effect relationships between turbulent flow ...

The pressures from the lower lip on the lower incisors were measured at the midline between the central incisors and between the left lateral incisor and canine. The measurements were made with the lip at rest and during swallowing of water in 24 boys and 40 girls aged 9-15 years. ...

The purpose of the study was to compare the effects of changing sound pressure level (SPL) and rate on respiratory, phonatory, and articulatory behavior during sentence production. Ten subjects, 5 men and 5 women, repeated the sentence, "I sell a sapapple again," under 5 SPL and 5 rate conditions. From ...

A model experiment was reported to be successful in simulating the propagation of sonic booms through a turbulent atmosphere [B. Lipkens and D. T. Blackstock, J. Acoust. Soc. Am. 103, 148-158 (1998)]. In this study the effect on N wave characteristics of turbulence intensity and propagation distance through turbulence are ...

The general impact of high intensity sound exposure on 25 guinea pigs was investigated at three different levels of arousal: 10 during general anaesthesia. 10 during partial arousal, and 5 during complete arousal. Parameters recorded before and during noise exposure were mean arterial blood pressure, pulse rate, and plasma norepinephrine ...

1. The vasospasm of primary Raynaud's disease can be triggered by acute emotional stress. We have studied the pattern of cardiovascular response evoked by acute emotional stress, a sound stimulus of 90 dB, 2 kHz for 30 s, in eight subjects with primary Raynaud's disease and in eight age- and ...

Midfacial hypoplasia following primary cleft lip repair is a common clinical correlate. Recent experimental work has suggested that increased lip pressure following an undermined lip repair may contribute to midfacial growth inhibition. Soft-tissue expansion has been used to generate additional soft tissue for reconstruction in the cranial region. The use ...

OBJECTIVE: The objective of this study was to determine the influence of velopharyngeal (VP) inadequacy on respiratory speech compensations. DESIGN: The pressure-flow technique was used to measure pressure, airflow, and timing variables associated with VP closure during the production of the initial plosive consonant /p/ in a series of the ...

Blood pressure presentation mode and personality are likely to influence biofeedback outcome. Thirty-six normotensive subjects were randomly assigned to visual or auditory continuous systolic feedback. "Distracting speech" and "broad band noise" were also superimposed and the effect on the biofeedback response was investigated. Psychological influence was also investigated. Systolic pressure ...

Recent experimental studies have shown the existence of optimal values of the glottal width and convergence angle, at which the phonation threshold pressure is minimum. These results indicate the existence of an optimal glottal configuration for ease of phonation, not predicted by the previous theory. In this paper, the origin ...

Although many studies have been performed on the effects of acoustic overstimulation on the inner ear, our knowledge about the cellular processes underlying reduced hearing sensitivity and auditory cell death is still limited. In order to further our understanding of cellular processes occurring in conjunction with acoustic trauma, we designed ...

The purpose of this study was to determine the effects of an intraoral air pressure target on estimation of laryngeal airway resistance (LAR) in normal children. Ten children produced the syllable /pi/ (a) with self-determined normal loudness, (b) with increased loudness, and (c) at a predetermined intraoral air pressure level ...

We propose a new technique for automated indirect blood pressure measurement based on the auscultatory method. Systolic, diastolic and blood mean pressure are identified by looking at trend changes in the spectral energy dispersion of Korotkoff sounds. The detection is solely based on patient measurements, not on population studies. By ...

A 57-year-old woman was admitted for examination because of chest discomfort. Transthoracic echocardiography was performed and she was diagnosed as having hypertrophic cardiomyopathy. An echocardiogram also revealed that she had midventricular obstruction with a pressure gradient of 125 mmHg determined by Doppler echocardiography. A phonocardiogram showed an early systolic sound ...

There is a gathering momentum favouring the adoption of the 5th Korotkoff sound to identify diastolic blood pressure in pregnancy. Our objective was to measure interobserver reliability for indirect blood pressure measurement in pregnancy for systolic and diastolic measurements and to calculate the difference in diastolic pressure measured by the ...

To quantify lip function in 16 patients with Parkinson's disease, a computerized semiconductor lip pressure transducer system was used prior to subjects being administered oral levodopa and at approximately 0.5 hr, 1.5 hr, and 3.0 hr postmedication. Two blood samples were taken from each subject at varying times during the ...