Passive Upper Airway Thermoregulation and High-Speed Assessment for Conventional versus Menthol Cigarette: Implications for Laryngeal Physiology

2020 ◽  
Vol 34 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Mary J. Sandage ◽  
Rita Patel
Keyword(s):  
High Speed ◽  
Upper Airway ◽  
Menthol Cigarette ◽  
Laryngeal Physiology

scholarly journals Effect of inhaled carbon dioxide on laryngeal abduction

2015 ◽  
Vol 118 (4) ◽  
pp. 489-494 ◽  
Author(s):  
Jonathan Cheetham ◽  
Amanda Jones ◽  
Manuel Martin-Flores
Keyword(s):  
Laryngeal Mask Airway ◽  
High Speed ◽  
Upper Airway ◽  
Laryngeal Mask ◽  
Maximal Response ◽  
High Temporal Resolution ◽  
Respiratory Drive ◽  
Laryngeal Function ◽  
Airway Patency ◽  
End Tidal

Hypercapnia produces a profound effect on respiratory drive and upper airway function to maintain airway patency. Previous work has evaluated the effects of hypercapnia on the sole arytenoid abductor, the posterior cricoarytenoid (PCA), using indirect measures of function, such as electromyography and direct nerve recording. Here we describe a novel method to evaluate PCA function in anesthetized animals and use this method to determine the effects of hypercapnia on PCA function. Eight dogs were anesthetized, and a laryngeal mask airway was used, in combination with high-speed videoendoscopy, to evaluate laryngeal function. A stepwise increase in inspired partial pressure of CO2 produced marked arytenoid abduction above 70-mmHg end-tidal CO2 (ETCO2) ( P < 0.001). Glottic length increased above 80-mmHg ETCO2 ( P < 0.02), and this lead to underrepresentation of changes in glottic area, if standard measures of glottic area (normalized glottic gap area) were used. Use of a known scale to determine absolute glottic area demonstrated no plateau with increasing ETCO2 up to 120 mmHg. Ventilatory parameters also continued to increase with no evidence of a maximal response. In a second anesthetic episode, repeated bursts of transient hypercapnia for 60 s with an ETCO2 of 90 mmHg produced a 43–55% increase in glottic area ( P < 0.001) at or shortly after the end of the hypercapnic burst. A laryngeal mask airway can be used in combination with videoendoscopy to precisely determine changes in laryngeal dimensions with high temporal resolution. Absolute glottic area more precisely represents PCA function than normalized glottic gap area at moderate levels of hypercapnia.

scholarly journals High-speed upper-airway imaging using full-range optical coherence tomography

2012 ◽  
Vol 17 (11) ◽  
pp. 110507 ◽  
Author(s):  
Joseph Jing ◽  
Jun Zhang ◽  
Anthony Chin Loy ◽  
Brian J. F. Wong ◽  
Zhongping Chen
Keyword(s):  
Optical Coherence Tomography ◽  
High Speed ◽  
Full Range ◽  
Upper Airway ◽  
Optical Coherence

scholarly journals Dynamic upper respiratory abnormalities in Thoroughbred racehorses in South Africa

2014 ◽  
Vol 85 (1) ◽  
Author(s):  
Javier E. Mirazo ◽  
Patrick Page ◽  
Luis Rubio-Martinez ◽  
Hendrick J. Marais ◽  
Catriona Lyle
Keyword(s):  
South Africa ◽  
High Speed ◽  
Upper Airway ◽  
Poor Performance ◽  
Maximum Speed ◽  
Upper Respiratory Tract ◽  
Thoroughbred Racehorses ◽  
Upper Respiratory ◽  
Track Surface ◽  
Multiple Abnormalities

Upper airway endoscopy at rest has been the diagnostic method of choice for equine upper respiratory tract (URT) conditions. Development of high-speed treadmill endoscopy improved the sensitivity of URT endoscopy by allowing observation of the horse’s nasopharynx and larynx during exercise. However, treadmill exercise may not always accurately represent the horse’s normal exercise as track surface, rider, tack and environmental variables are altered. Recently, the development of dynamic overground endoscopy (DOE) has addressed some of these shortcomings. A retrospective study was undertaken to describe the URT abnormalities detected during DOE in racehorses presenting with poor performance and/or abnormal respiratory noise. Patient records of Thoroughbred racehorses undergoing DOE from November 2011 to August 2012 were reviewed. Data collected included signalment, primary complaint, distance exercised, maximum speed and dynamic airway abnormalities detected. Fifty-two horses underwent DOE for investigation of poor performance and/or abnormal respiratory noise. The main abnormalities detected included axial deviation of the aryepiglottic folds (40%), vocal cord collapse (35%), abnormal arytenoid function (33%) and dorsal displacement of the soft palate (25%). A total of 40 horses were diagnosed with one or more abnormalities of the URT (77%). Fifteen horses (29%) had a single abnormality and 25 horses (48%) had multiple abnormalities. This study showed that DOE is a useful technique for investigating dynamic disorders of the URT in racehorses in South Africa. The total number and type of dynamic pathological conditions were comparable with those identified in similar populations in other geographical locations.

Ultra High Speed Photography in Laryngeal Physiology

1962 ◽  
Vol 27 (2) ◽  
pp. 165-171 ◽  
Author(s):  
G. Paul Moore ◽  
Frazer D. White ◽  
Hans Von Leden
Keyword(s):  
High Speed ◽  
High Speed Photography ◽  
Ultra High Speed ◽  
Laryngeal Physiology

scholarly journals Ventilation-induced jet suggests biotrauma in reconstructed airways of the intubated neonate

2020 ◽  
Vol 17 (162) ◽  
pp. 20190516 ◽  
Author(s):  
Eliram Nof ◽  
Metar Heller-Algazi ◽  
Filippo Coletti ◽  
Dan Waisman ◽  
Josué Sznitman
Keyword(s):  
High Speed ◽  
Neonatal Intensive Care ◽  
Invasive Mechanical Ventilation ◽  
Three Dimensional ◽  
Upper Airway ◽  
Jet Impingement ◽  
Bronchial Epithelium ◽  
Synthetic Jet ◽  
High Frequency Ventilation ◽  
Frequency Ventilation

We investigate respiratory flow phenomena in a reconstructed upper airway model of an intubated neonate undergoing invasive mechanical ventilation, spanning conventional to high-frequency ventilation (HFV) modes. Using high-speed tomographic particle image velocimetry, we resolve transient, three-dimensional flow fields and observe a persistent jet flow exiting the endotracheal tube whose strength is directly modulated according to the ventilation protocol. We identify this synthetic jet as the dominating signature of convective flow under intubated ventilation. Concurrently, our in silico wall shear stress analysis reveals a hitherto overlooked source of ventilator-induced lung injury as a result of jet impingement on the tracheal carina, suggesting damage to the bronchial epithelium; this type of injury is known as biotrauma. We find HFV advantageous in mitigating the intensity of such impingement, which may contribute to its role as a lung protective method. Our findings may encourage the adoption of less invasive ventilation procedures currently used in neonatal intensive care units.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

The on-line use of histogram data for high-speed correction and alignment of electron microscope images

1984 ◽  
Vol 42 ◽  
pp. 556-557
Author(s):  
William Krakow
Keyword(s):  
Power Spectrum ◽  
High Speed ◽  
Direct Memory Access ◽  
Digital Television ◽  
Contrast Transfer Function ◽  
The Past ◽  
High Resolution Tem ◽  
On Line ◽  
Correction Of Astigmatism ◽  
The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

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