Role of respiratory heat exchange in production of exercise-induced asthma

1979 ◽  
Vol 46 (3) ◽  
pp. 467-475 ◽  
Author(s):  
E. C. Deal ◽  
E. R. McFadden ◽  
R. H. Ingram ◽  
R. H. Strauss ◽  
J. J. Jaeger
Keyword(s):  
Heat Exchange ◽  
Thermal Load ◽  
Tracheobronchial Tree ◽  
Total Heat Flux ◽  
Random Fashion ◽  
Theoretical Predictions ◽  
Per Se ◽  
Exercise Induced ◽  
Respiratory Heat Exchange

We have hypothesized that it is the total heat flux in the tracheobronchial tree during exercise that determines the degree of postexertional obstruction in asthma, and have developed quanititative expressions that relate these two events. We tested this hypothesis by comparing the observed responses to exercise, while our subjects inhaled dry air at various temperatures ranging from subzero to 80 degrees C in a random fashion, to those that we predicted would occur based upon calculations of respiratory heat exchange. We further determined if heat could be transferred from the inspired air to the mucosa so as to offset evaporative losses from the airways. The observed responses fell as air temperature was increased from -11 to +37 degrees C and exactly matched theoretical predictions. Above 37 degrees C, the observed response exceeded predictions, indicating that it was not possible to provide sufficient heat per se in the air to offset the vaporization of water. However, when small amounts of water vapor were added to the inspirate at high temperatures, bronchospasm was virtually abolished and the response again closely matched theoretical expectations. We conclude that the magnitude of exercise-induced asthma is directly proportional to the thermal load placed on the airways and that this reaction is quantifiable in terms of respiratory heat exchange.

Role of respiratory heat exchange in asthma

1984 ◽  
Vol 57 (2) ◽  
pp. 608-609 ◽  
Author(s):  
E. C. Deal ◽  
E. R. McFadden ◽  
R. H. Ingram ◽  
J. J. Jaeger
Keyword(s):  
Heat Exchange ◽  
Respiratory Heat Exchange

A Microcomputer-Based Respiratory Heat Exchange Facility for Use in the Diagnosis of Thermally Induced Asthma

1989 ◽  
Vol 203 (1) ◽  
pp. 43-48 ◽  
Author(s):  
R D Farley ◽  
K R Patel
Keyword(s):  
Heat Exchange ◽  
Heat Loss ◽  
Ambient Air ◽  
Pilot Studies ◽  
Cold Air ◽  
Thermally Induced ◽  
Air Supply ◽  
Lung Dysfunction ◽  
Exercise Induced ◽  
Respiratory Heat Exchange

Exercise-induced asthma is prevalent in many asthmatics and during the winter months can be exacerbated by cold air inhalation. A laboratory facility was required to permit early diagnosis of cold air sensitivity in these patients. This paper describes the development of a modular air conditioning system to produce a range of inhalative thermal burdens and the microcomputer interfacing to measure the rate of airway heat loss imposed. A single-stage refrigerator was built capable of cooling 150 1/min air to —25°C. This was also used to generate dry ambient temperature air by rewarming the chilled air supply. An air humidifier was developed based upon natural convection and evaporation. It was capable of raising 150 1/min ambient air to 37°C, 100 per cent relative humidity. In two pilot studies of 18 asthmatics it was found that the rate of respiratory heat exchange could be correlated with the magnitude of post exertional bronchoconstriction (lung dysfunction) and that exercise-induced asthma could be minimized by attenuating the rate of airway heat loss.

Respiratory heat and water exchange: physiological and clinical implications

1983 ◽  
Vol 54 (2) ◽  
pp. 331-336 ◽  
Author(s):  
E. R. McFadden
Keyword(s):  
Heat Exchange ◽  
Water Exchange ◽  
Tracheobronchial Tree ◽  
Clinical Implications ◽  
Extreme Conditions ◽  
Thermal Gradients ◽  
Mucociliary Transport ◽  
Transport Mechanisms ◽  
Upper Airways ◽  
Respiratory Heat Exchange

Recent evidence demonstrates that the conditioning of inspired air is not confined to the upper airways as formerly thought but rather involves as much of the tracheobronchial tree as necessary to complete the process. As the need to condition more air is increased by raising ventilation and/or lowering inspired temperature (and so water content), the point at which the inspirate reaches body conditions moves progressively deeper into the lungs, and under extreme conditions thermal transfers can be measured in airways less than 2 mm in diameter. The decrease in airway temperature that develops from the movement of heat and water from the mucosa during inspiration not only facilitates recovery during expiration by reversing the thermal gradients, but it may also produce airway obstruction in susceptible individuals by an as yet undefined mechanism. Respiratory heat exchange may also interact with airway secretory processes and mucociliary transport mechanisms and may help regulate bronchial blood supply.

Exercise-Induced Fibrinolysis – Fact or Fiction?

1982 ◽  
Vol 48 (02) ◽  
pp. 201-203 ◽  
Author(s):  
N A Marsh ◽  
P J Gaffney
Keyword(s):  
Plasminogen Activator ◽  
Degradation Products ◽  
Coagulation Factors ◽  
Vascular Wall ◽  
Strenuous Exercise ◽  
Fibrin Degradation Products ◽  
Real Increase ◽  
Exercise Induced ◽  
Male Subjects

SummaryThe effect of strenuous exercise on the fibrinolytic and coagulation mechanisms was examined in six healthy male subjects. Five min bicycle exercise at a work-rate of 800 to 1200 kpm. min−1 produced an abrupt increase in plasma plasminogen activator levels which disappeared after 90 min. However, there was no change in early or late fibrin degradation products nor was there a change in fibrinopeptide A levels or βthromboglobulin levels after exercise although activated partial thromboplastin times were significantly shortened. It is concluded that strenuous exercise does not produce any real increase in fibrinogen-fibrin conversion nor any real increase in the breakdown of these proteins. The role of exercise-induced release of plasminogen activator remains unclear, but probably helps to maintain plasma levels in a discontinuous manner concurrently with the continuous low-level secretion from the vascular wall. The shortening of partial thromboplastin time may be due to the raised levels of plasminogen activator changing the activation state of other coagulation factors.

Role of the sympathoadrenal system in exercise-induced inhibition of insulin secretion. Effects of islet transplantation

Diabetes ◽  
1995 ◽  
Vol 44 (5) ◽  
pp. 565-571 ◽  
Author(s):  
H. Houwing ◽  
K. M. Frankel ◽  
J. H. Strubbe ◽  
P. T. van Suylichem ◽  
A. B. Steffens
Keyword(s):  
Insulin Secretion ◽  
Islet Transplantation ◽  
Sympathoadrenal System ◽  
Exercise Induced

Parliament as the Foreign Policy Actor: the Resources of the Parliamentary Diplomacy

2018 ◽  
Vol 42 ◽  
pp. 316-321
Author(s):  
Boris I. Ananyev ◽  
Daniil A. Parenkov
Keyword(s):  
Foreign Policy ◽  
International Security ◽  
New Technologies ◽  
Conservative Approach ◽  
National Interests ◽  
Policy Actor ◽  
Security Challenges ◽  
Essential Idea ◽  
Per Se

The aim of the article is to show the role of parliament in the foreign policy within the framework of the conservative school of thought. The authors examine both Russian and Western traditions of conservatism and come to the conclusion that the essential idea of “the rule of the best” has turned to be one of the basic elements of the modern legislative body per se. What’s more, parliament, according to the conservative approach, tends to be the institution that represents the real spirit of the nation and national interests. Therefore the interaction of parliaments on the international arena appears to be the form of the organic communication between nations. Parliamentary diplomacy today is the tool that has the potential to address to the number of issues that are difficult to deal with within the framework of the traditional forms of IR: international security, challenges posed by new technologies, international sanctions and other.

Gedanken zu Genesis 46,8–27

2019 ◽  
Vol 63 (1) ◽  
pp. 93-104
Author(s):  
Wilfried Warning
Keyword(s):  
Close Reading ◽  
Per Se ◽  
Distinct Distribution

Abstract In general, commentators consider Gen 46:8–27 as a secondary addition. Close reading brings to light the structuring role of verses 18 and 25 („these were the sons of Zilpah / Bilhah … and these she bore to Jacob, sixteen souls / seven souls”). In a ten-part outline based on the personal name (PN) „Jacob” v. 18 takes the fourth and v.25 the fourth from last positions. In Genesis 37–50 the noun נפש „soul” occurs thirteen times – now v. 18 takes the sixth and v. 25 the sixth-from-last positions. The thirteen-part table based on the PN „Ruben” stands out for two reasons: Firstly, in Genesis the term „Ruben the first born of Jacob” shows up only twice, namely in the first (34,23) and last (46,8) texts. Secondly, as regards content 37,22 and 42,22 are correlated. In the 13-part outline they take the sixth and sixth-from-last positions respectively. The distinct distribution of these terms indicates that the passage per se is well structured and, what is more, at the same time it has been skillfully integrated in Gen 37–50 and in the Jacob-Joseph cycle.

An Experimental Investigation of Auditors' Liability: Implications for Social Welfare and Exploration of Deviations from Theoretical Predictions

2000 ◽  
Vol 75 (4) ◽  
pp. 429-451 ◽  
Author(s):  
Ronald R. King ◽  
Rachel Schwartz
Keyword(s):  
Experimental Investigation ◽  
Social Welfare ◽  
Strict Liability ◽  
Liability Rule ◽  
Optimal Response ◽  
Legal Regimes ◽  
Theoretical Predictions ◽  
Best Responses

This paper reports the results of an experiment designed to investigate how legal regimes affect social welfare. We investigate four legal regimes, each consisting of a liability rule (strict or negligence) and a damage measure (out-of-pocket or independent-of-investment). The results of the experiment are for the most part consistent with the qualitative predictions of Schwartz's (1997) model; however, subjects' actual choices deviate from the point predictions of the model. We explore whether these deviations arise because: (1) subjects form faulty anticipations of their counterparts' actions and/or (2) subjects do not choose the optimal responses given their anticipations. We find that subjects behave differently under the four regimes in terms of anticipation errors and departures from best responses. For example, subjects playing the role of auditors anticipate investments most accurately under the regime with strict liability combined with out-of-pocket damages, but are least likely to choose the optimal response given their anticipations. This finding implies that noneconomic factors likely play a role in determining subjects' choices.

scholarly journals A Stochastic Kinetic Type Reactions Model for COVID-19

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1221
Author(s):  
Giorgio Sonnino ◽  
Fernando Mora ◽  
Pasquale Nardone
Keyword(s):  
Real Data ◽  
Stochastic Noise ◽  
Mathematical Basis ◽  
Sis Model ◽  
Theoretical Predictions ◽  
Coronavirus Infection ◽  
Massive Distribution ◽  
Second Wave ◽  
Stochastic Sis Model

We propose two stochastic models for the Coronavirus pandemic. The statistical properties of the models, in particular the correlation functions and the probability density functions, were duly computed. Our models take into account the adoption of lockdown measures as well as the crucial role of hospitals and health care institutes. To accomplish this work we adopt a kinetic-type reaction approach where the modelling of the lockdown measures is obtained by introducing a new mathematical basis and the intensity of the stochastic noise is derived by statistical mechanics. We analysed two scenarios: the stochastic SIS-model (Susceptible ⇒ Infectious ⇒ Susceptible) and the stochastic SIS-model integrated with the action of the hospitals; both models take into account the lockdown measures. We show that, for the case of the stochastic SIS-model, once the lockdown measures are removed, the Coronavirus infection will start growing again. However, the combined contributions of lockdown measures with the action of hospitals and health institutes is able to contain and even to dampen the spread of the SARS-CoV-2 epidemic. This result may be used during a period of time when the massive distribution of vaccines in a given population is not yet feasible. We analysed data for USA and France. In the case of USA, we analysed the following situations: USA is subjected to the first wave of infection by Coronavirus and USA is in the second wave of SARS-CoV-2 infection. The agreement between theoretical predictions and real data confirms the validity of our approach.

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