Relationship between alae nasi activation and breathing route during exercise in humans

We studied the relationship between alae nasi muscle (AN) activation and breathing route in normal subjects during exercise. Nasal and oral airflow were measured simultaneously using a partitioned face mask and were recorded with the AN electromyogram. Subjects breathed via 1) the nose and mouth (NM) 2) the nose only (N), or 3) the mouth only (M). As ventilation (VE) rose progressively, the peak phasic inspiratory AN activity (IAAN) increased for all breathing routes. IAAN during N [11.8 +/- 2.0 arbitrary units (AU)] was greater than during NM (3.3 +/- 1.3 AU) and M (2.4 +/- 1.0 AU; P less than 0.01) measured at the highest common VE (over a 10-l/min range). At the highest 20% of IAAN recorded during NM, the total VE during N (24 +/- 5 l/min). However, for the same IAAN, nasal VE during NM (27 +/- 3 l/min) was similar to that during N. Thus, as ventilation increases during exercise, AN activity and nasal ventilation are tightly correlated, independently of flow through the mouth. This suggests either reflex modulation of AN activity by nasal flow or coordination of AN activation with the flow-partitioning mechanism of the upper airway.

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Oronasal partitioning of ventilation during exercise in humans

Journal of Applied Physiology ◽

10.1152/jappl.1991.71.2.546 ◽

1991 ◽

Vol 71 (2) ◽

pp. 546-551 ◽

Cited By ~ 17

Author(s):

J. R. Wheatley ◽

T. C. Amis ◽

L. A. Engel

Keyword(s):

Upper Airway ◽

Normal Subjects ◽

Face Mask ◽

Inspiratory Flow ◽

Mean Flow ◽

Total Flow ◽

Progressive Exercise ◽

Expiratory Flow ◽

Exercise In Humans

The partitioning of oronasal breathing was studied in five normal subjects during progressive exercise. Subjects performed three to five identical runs, each consisting of four 1-min work periods at increments of 50 W. Nasal and oral airflow were measured simultaneously using a partitioned face mask both during and for 4 min after exercise. Total mean flows were the sum of nasal and oral flows. At a total mean inspiratory flow of 2 l/s, the nasal fraction of total flow was 0.36 +/- 0.04 (SE) and decreased by 6 +/- 3% between total flows of 1.5 and 2.5 l/s. Throughout exercise, the nasal fraction of total mean inspiratory flow did not differ from that of total expiratory flow and was similar to that of total mean inspiratory flow during the postexercise period at a corresponding total mean flow (both P greater than 0.02). The results show that oronasal flow partitioning is not directly due to the exercise itself but is related to the level of ventilation and is uninfluenced by the direction of upper airway flow (i.e., inspiratory vs. expiratory). These findings suggest tightly controlled modulation of the relative resistances of the oral and/or nasal pathways.

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Influence of nasal airflow temperature and pressure on alae nasi electrical activity

Journal of Applied Physiology ◽

10.1152/jappl.1991.71.6.2283 ◽

1991 ◽

Vol 71 (6) ◽

pp. 2283-2291 ◽

Cited By ~ 7

Author(s):

J. R. Wheatley ◽

T. C. Amis ◽

L. A. Engel

Keyword(s):

Upper Airway ◽

Normal Subjects ◽

Face Mask ◽

Emg Activity ◽

Nasal Airflow ◽

Nasal Breathing ◽

Oral Breathing ◽

The Subject ◽

Temperature And Pressure ◽

Nasal Flow

The influence of nasal airflow, temperature, and pressure on upper airway muscle electromyogram (EMG) was studied during steady-state exercise in five normal subjects. Alae nasi (AN) and genioglossus EMG activity was recorded together with nasal and oral airflows and pressures measured simultaneously by use of a partitioned face mask. At constant ventilations between 30 and 50 l/min, peak inspiratory AN activity during nasal breathing (7.2 +/- 1.4 arbitrary units) was greater than that during oral breathing (1.0 +/- 0.3 arbitrary units; P less than 0.005). In addition, the onset of AN EMG activity preceded inspiratory flow by 0.38 +/- 0.03 s during nasal breathing but by only 0.17 +/- 0.04 s during oral breathing (P less than 0.04). When the subject changed from nasal to oral breathing, both these differences were apparent on the first breath. However, peak AN activity during nasal breathing was uninfluenced by inspiration of hot saturated air (greater than 40 degrees C), by external inspiratory nasal resistance, or by changes in the expiratory route. The genioglossus activity did not differ between nasal and oral breathing (n = 2). Our findings do not support reflex control of AN activity sensitive to nasal flow, temperature, or surface pressure. We propose a centrally controlled feedforward modulation of phasic inspiratory AN activity linked with the tonic drive to the muscles determining upper airway breathing route.

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Vocal Tract Steadiness

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3504.761 ◽

1992 ◽

Vol 35 (4) ◽

pp. 761-768 ◽

Cited By ~ 30

Author(s):

Petra Zwirner ◽

Gary J. Barnes

Keyword(s):

Motor Control ◽

Fundamental Frequency ◽

Vocal Tract ◽

Upper Airway ◽

Normal Subjects ◽

Subject Group ◽

Formant Frequency ◽

Control Subjects ◽

Acoustic Analyses ◽

The Relationship

Acoustic analyses of upper airway and phonatory stability were conducted on samples of sustained phonation to evaluate the relation between laryngeal and articulomotor stability for 31 patients with dysarthria and 12 non-dysarthric control subjects. Significantly higher values were found for the variability in fundamental frequency and formant frequency of patients who have Huntington’s disease compared with normal subjects and patients with Parkinson’s disease. No significant correlations were found between formant frequency variability and the variability of the fundamental frequency for any subject group. These findings are discussed as they pertain to the relationship between phonatory and upper airway subsystems and the evaluation of vocal tract motor control impairments in dysarthria.

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Induction of upper airway occlusion in sleeping individuals with subatmospheric nasal pressure

Journal of Applied Physiology ◽

10.1152/jappl.1988.64.2.535 ◽

1988 ◽

Vol 64 (2) ◽

pp. 535-542 ◽

Cited By ~ 236

Author(s):

A. R. Schwartz ◽

P. L. Smith ◽

R. A. Wise ◽

A. R. Gold ◽

S. Permutt

Keyword(s):

Critical Pressure ◽

Upper Airway ◽

Nrem Sleep ◽

Normal Subjects ◽

Nasal Mask ◽

Airway Occlusion ◽

Upstream Pressure ◽

Normal Human ◽

Nasal Pressure ◽

The Relationship

In collapsible biologic conduits, occlusion and cessation of flow occur when upstream pressure falls below a critical pressure (Pcrit). To examine the relationship between Pcrit and the development of upper airway occlusion, we examined the relationship between maximal inspiratory airflow and nasal pressure in seven normal subjects during sleep. At varying levels of subatmospheric pressure applied to a nasal mask during non-rapid-eye-movement (NREM) sleep, maximal inspiratory airflow decreased in proportion to the level of nasal pressure. When nasal pressure fell below a Pcrit, subjects demonstrated upper airway occlusions terminated by arousals. In these normal subjects, the upper airway Pcrit was found to be -13.3 +/- 3.2 (SD) cmH2O. In four subjects who sustained sleep while nasal pressure remained below the Pcrit, recurrent occlusive apneas were demonstrated. The relationship between maximal inspiratory airflow and nasal pressure in each subject was fit by linear regression and demonstrated upper airway Pcrit at the zero-flow intercept that were not significantly different from those observed experimentally. These data demonstrate that the normal human upper airway during sleep is characterized by a negative Pcrit and that occlusion may be induced when nasal pressure is decreased below this Pcrit.

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Nonlinear Analysis of Visual Evoked Potentials Elicited by Color Stimulation

Methods of Information in Medicine ◽

10.1055/s-0038-1636871 ◽

1997 ◽

Vol 36 (04/05) ◽

pp. 315-318 ◽

Cited By ~ 3

Author(s):

K. Momose ◽

K. Komiya ◽

A. Uchiyama

Keyword(s):

Visual System ◽

Evoked Potentials ◽

Visual Evoked Potentials ◽

Normal Subjects ◽

Second Order ◽

First Order ◽

The Relationship ◽

Perceived Color ◽

Second Order Nonlinearity ◽

Visual Evoked

Abstract:The relationship between chromatically modulated stimuli and visual evoked potentials (VEPs) was considered. VEPs of normal subjects elicited by chromatically modulated stimuli were measured under several color adaptations, and their binary kernels were estimated. Up to the second-order, binary kernels obtained from VEPs were so characteristic that the VEP-chromatic modulation system showed second-order nonlinearity. First-order binary kernels depended on the color of the stimulus and adaptation, whereas second-order kernels showed almost no difference. This result indicates that the waveforms of first-order binary kernels reflect perceived color (hue). This supports the suggestion that kernels of VEPs include color responses, and could be used as a probe with which to examine the color visual system.

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The Relationship of Root Mean Square Value of Electromyography and Isometric Torque of Quadriceps in Normal Subjects

Rehabilitation Medicine ◽

10.3724/spj.1329.2016.01.058 ◽

2016 ◽

Vol 26 (1) ◽

pp. 58

Author(s):

Qiurong XIE ◽

Zheng JIANG ◽

Qinglu LUO ◽

Jie LIANG ◽

Xiaoling WANG ◽

...

Keyword(s):

Root Mean Square ◽

Normal Subjects ◽

Mean Square ◽

Isometric Torque ◽

Relationship Of ◽

The Relationship

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Effect of Head Elevation on Passive Upper Airway Collapsibility in Normal Subjects during Propofol Anesthesia

Anesthesiology ◽

10.1097/aln.0b013e318223ba6d ◽

2011 ◽

Vol 115 (2) ◽

pp. 273-281 ◽

Cited By ~ 16

Author(s):

Masato Kobayashi ◽

Takao Ayuse ◽

Yuko Hoshino ◽

Shinji Kurata ◽

Shunji Moromugi ◽

...

Keyword(s):

Upper Airway ◽

Normal Subjects ◽

Target Concentration ◽

Airway Patency ◽

Head Elevation ◽

Jaw Opening ◽

Airway Collapsibility ◽

Upper Airway Collapsibility ◽

Head Flexion ◽

Male Subjects

Background Head elevation can restore airway patency during anesthesia, although its effect may be offset by concomitant bite opening or accidental neck flexion. The aim of this study is to examine the effect of head elevation on the passive upper airway collapsibility during propofol anesthesia. Method Twenty male subjects were studied, randomized to one of two experimental groups: fixed-jaw or free-jaw. Propofol infusion was used for induction and to maintain blood at a constant target concentration between 1.5 and 2.0 μg/ml. Nasal mask pressure (PN) was intermittently reduced to evaluate the upper airway collapsibility (passive PCRIT) and upstream resistance (RUS) at each level of head elevation (0, 3, 6, and 9 cm). The authors measured the Frankfort plane (head flexion) and the mandible plane (jaw opening) angles at each level of head elevation. Analysis of variance was used to determine the effect of head elevation on PCRIT, head flexion, and jaw opening within each group. Results In both groups the Frankfort plane and mandible plane angles increased with head elevation (P < 0.05), although the mandible plane angle was smaller in the free-jaw group (i.e., increased jaw opening). In the fixed-jaw group, head elevation decreased upper airway collapsibility (PCRIT ~ -7 cm H₂O at greater than 6 cm elevation) compared with the baseline position (PCRIT ~ -3 cm H₂O at 0 cm elevation; P < 0.05). Conclusion : Elevating the head position by 6 cm while ensuring mouth closure (centric occlusion) produces substantial decreases in upper airway collapsibility and maintains upper airway patency during anesthesia.

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Observation of Pressure Drop Behavior in an Operating Fuel Cell Stack

ASME 2005 Power Conference ◽

10.1115/pwr2005-50074 ◽

2005 ◽

Author(s):

Frano Barbir ◽

Haluk Gorgun ◽

Xinting Wang

Keyword(s):

Fuel Cell ◽

Pressure Drop ◽

Proton Exchange Membrane ◽

Proton Exchange ◽

Cathode Side ◽

Fuel Cell Stack ◽

Flow Through ◽

Drying Conditions ◽

Exchange Membrane ◽

The Relationship

Pressure drop on the cathode side of a PEM (Proton Exchange Membrane) fuel cell stack has been studied and used as a diagnostic tool. Since the Reynolds number at the beginning of the flow field channel was <250, the flow through the channel is laminar, and the relationship between the pressure drop and the flow rate is linear. Some departure from linearity was observed when water was either introduced in the stack or produced inside the stack in the electrochemical reaction. By monitoring the pressure drop in conjunction with the cell resistance in an operational fuel cell stack, it was possible to diagnose either flooding or drying conditions inside the stack.

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