Measurement of Respiration and Respiratory Responses During Inhalation Exposures

1990 ◽  
Vol 9 (4) ◽  
pp. 397-405 ◽  
Author(s):  
Joe L. Mauderly
Keyword(s):  
Breathing Pattern ◽  
Physiological Responses ◽  
Hot Wire ◽  
Advantages And Disadvantages ◽  
Controlled Breathing ◽  
Measurement Devices ◽  
Low Volume ◽  
Respiratory Measurement ◽  
Respiratory Responses

This report reviews approaches for making measurements of the respiration of subjects during inhalation exposures. Respiration is measured to quantitate the volume of exposure material inhaled, to evaluate the normalcy and steadiness of respiration during exposure, to relate breathing pattern to deposition or uptake of inhaled materials, to detect physiological responses to inhaled materials, and to monitor respiration during controlled breathing. A small number of basic devices are commonly used during exposures, including nonrebreathing valves, pneumotachographs, spirometers, and plethysmographs. Less frequently used devices adaptable for use during exposures include hot wire anemometers, respiratory-inductive plethysmographs, and impedance pneumographs. These devices, some of their potential uses, and their advantages and disadvantages are described and useful references are given. Several useful combinations of respiratory measurement devices are suggested for low-volume, bag-to-bag, and immersion exposure systems.

scholarly journals Physiological Responses to Low-Volume Interval Training in Women

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lauren E. Skelly ◽  
Celine Bailleul ◽  
Jenna B. Gillen
Keyword(s):  
Skeletal Muscle ◽  
Cardiorespiratory Fitness ◽  
Adaptive Response ◽  
Physiological Responses ◽  
Interval Training ◽  
Evidence Base ◽  
Moderate Intensity ◽  
Continuous Training ◽  
Low Volume ◽  
High Intensity Interval

AbstractInterval training is a form of exercise that involves intermittent bouts of relatively intense effort interspersed with periods of rest or lower-intensity exercise for recovery. Low-volume high-intensity interval training (HIIT) and sprint interval training (SIT) induce physiological and health-related adaptations comparable to traditional moderate-intensity continuous training (MICT) in healthy adults and those with chronic disease despite a lower time commitment. However, most studies within the field have been conducted in men, with a relatively limited number of studies conducted in women cohorts across the lifespan. This review summarizes our understanding of physiological responses to low-volume interval training in women, including those with overweight/obesity or type 2 diabetes, with a focus on cardiorespiratory fitness, glycemic control, and skeletal muscle mitochondrial content. We also describe emerging evidence demonstrating similarities and differences in the adaptive response between women and men. Collectively, HIIT and SIT have consistently been demonstrated to improve cardiorespiratory fitness in women, and most sex-based comparisons demonstrate similar improvements in men and women. However, research examining insulin sensitivity and skeletal muscle mitochondrial responses to HIIT and SIT in women is limited and conflicting, with some evidence of blunted improvements in women relative to men. There is a need for additional research that examines physiological adaptations to low-volume interval training in women across the lifespan, including studies that directly compare responses to MICT, evaluate potential mechanisms, and/or assess the influence of sex on the adaptive response. Future work in this area will strengthen the evidence-base for physical activity recommendations in women.

scholarly journals Controlled versus free breathing for multiple breath nitrogen washout in healthy adults

2020 ◽  
pp. 00435-2020
Author(s):  
Blake M. Handley ◽  
Edward Jeagal ◽  
Robin E. Schoeffel ◽  
Tanya Badal ◽  
David G. Chapman ◽  
...  
Keyword(s):  
Breathing Pattern ◽  
Free Breathing ◽  
Poor Correlation ◽  
Clinical Implementation ◽  
Repeated Testing ◽  
Nitrogen Washout ◽  
Ventilation Heterogeneity ◽  
Residual Capacity ◽  
Controlled Breathing ◽  
Adult Volunteers

Multiple breath nitrogen washout (MBNW) quantifies ventilation heterogeneity. Two distinct protocols are currently used for MBNW testing: “controlled breathing”, with targeted tidal volume (VT) and respiratory rate (RR); and “free breathing”, with no constraints on breathing pattern. Indices derived from the two protocols (functional residual capacity [FRC], lung clearance index [LCI], Scond, Sacin) have not been directly compared in adults. We aimed to determine whether MBNW indices are comparable between protocols, to identify factors underlying any between-protocol differences, and to determine the between-session variabilities of each protocol.We performed MBNW testing by both protocols in 27 healthy adult volunteers, applying the currently-proposed correction for VT to Scond and Sacin derived from free breathing. To establish between-session variability, we repeated testing in 15 volunteers within 3 months.While FRC was comparable between controlled versus free breathing (3.17(0.98) versus 3.18(0.94) L,p=0.88), indices of ventilation heterogeneity derived from the two protocols were not, with poor correlation for Scond (r=0.18,p=0.36) and significant bias for Sacin (0.057(0.021)L−1versus 0.085(0.038)L−1,p=0.0004). Between-protocol differences in Sacin were related to differences in the breathing pattern, i.e. VT (p=0.004) and RR (p=0.01), rather than FRC. FRC and LCI showed good between-session repeatability, but Scond and Sacin from free breathing showed poor repeatability with wide limits of agreement.These findings have implications for the ongoing clinical implementation of MBNW, as they demonstrate that Scond and Sacin from free breathing, despite VT correction, are not equivalent to the controlled breathing protocol. The poor between-session repeatability of Scond during free breathing may limit its clinical utility.

scholarly journals COMPARATIVE ANALYSIS OF RESPIRATORY REACTIONS TO MICROINJECTION OF GABA AND PENICILLIN INTO THE BOTZINGER COMPLEX AND THE PRE-BOTZINGER COMPLEX IN RATS

2017 ◽  
Vol 18 (3.1) ◽  
pp. 210-218
Author(s):  
N.G. Manshina ◽  
O.A. Vedyasova
Keyword(s):  
Comparative Analysis ◽  
Tidal Volume ◽  
Gaba Receptors ◽  
Inhibitory Action ◽  
Breathing Pattern ◽  
Local Administration ◽  
Bötzinger Complex ◽  
Gabaa Antagonist ◽  
Respiratory Responses

In acute experiments on anesthetized rats, the respiratory responses to local administration of GABA (10^{-5}М) and noncompetitive GABAA antagonist penicillin (10^{-7} М) into B¨otzinger complex (BC) and pre-B¨otzinger complex (PBC) were studied. The differences in the responses of respiratory frequency, inspiratory and expiratory duration after injection of GABA into the BC and PBC were found. The effects were more pronounced when GABA administered into the PBC. It is shown that the response of tidal volume, in contrast, was more frequent when both GABA and penicillin injected into the BC. The question of the role of GABA receptors of BC and PBC in the realization of the inhibitory action of GABA on the temporal and volumetric parameters of breathing pattern is discussed.

scholarly journals THE EFFECTS OF GASTRIN-RELEASING PEPTIDE MICROINJECTIONS INTO THE PRE-BOTZINGER COMPLEX ON THE RESPIRATORY PARAMETERS OF RATS

2017 ◽  
Vol 18 (6) ◽  
pp. 167-173
Author(s):  
A.A. Aliev ◽  
A.N. Inyushkin
Keyword(s):  
Tidal Volume ◽  
Breathing Pattern ◽  
Mechanisms Of Action ◽  
Respiratory Effects ◽  
Gastrin Releasing Peptide ◽  
Inspiratory Muscles ◽  
Respiratory Parameters ◽  
Bötzinger Complex ◽  
Respiratory Responses ◽  
Bursting Activity

In the article, the results of investigation of the respiratory effects of gastrinreleasing peptide microjections into the pre-Botzinger complex are presented. It was found that microinjections of neuropeptide induced an increase in respiratory rate, tidal volume, amplitude of diaphragm and external intercostal muscles bursting activity. The statistically significant respiratory responses observed when 10^-5 M of GRP was used, while 10^-8 M of GRP appeared to be sub-threshold and didn’t alter the breathing pattern and activity of inspiratory muscles. The suggested mechanisms of action of GRP at the level of pre-Botzinger complex are discussed.

The Effects of Precipitation on Cloud Droplet Measurement Devices

2009 ◽  
Vol 26 (7) ◽  
pp. 1404-1409 ◽  
Author(s):  
Brad Baker ◽  
Qixu Mo ◽  
R. Paul Lawson ◽  
Darren O’Connor ◽  
Alexei Korolev
Keyword(s):  
Cloud Droplet ◽  
Linear Functions ◽  
Hot Wire ◽  
Particle Volume ◽  
Cloud Liquid Water ◽  
Wire Probe ◽  
Precipitation Water ◽  
In Situ Observations ◽  
Measurement Devices

Abstract Aircraft in situ observations of precipitation during the Rain in Cumulus over the Ocean (RICO) field project are used to study and parameterize the effects of precipitation on cloud probes. Specifically, the effects of precipitation on the Forward Scattering Spectrometer Probe, the King cloud liquid water hot-wire probe, and the particle volume monitor are parameterized as linear functions of the precipitation water content.

Cryogenic atomic force microscopy

1991 ◽  
Vol 49 ◽  
pp. 54-55
Author(s):  
K. A. Fisher ◽  
M. G. L. Gustafsson ◽  
M. B. Shattuck ◽  
J. Clarke
Keyword(s):  
Room Temperature ◽  
Rapid Freezing ◽  
Cryogenic Temperatures ◽  
Soft Or ◽  
Electrically Conductive ◽  
Force Microscopy ◽  
Flexible Molecules ◽  
Advantages And Disadvantages ◽  
Atomic Force ◽  
Chemical Perturbation

The atomic force microscope (AFM) is capable of imaging electrically conductive and non-conductive surfaces at atomic resolution. When used to image biological samples, however, lateral resolution is often limited to nanometer levels, due primarily to AFM tip/sample interactions. Several approaches to immobilize and stabilize soft or flexible molecules for AFM have been examined, notably, tethering coating, and freezing. Although each approach has its advantages and disadvantages, rapid freezing techniques have the special advantage of avoiding chemical perturbation, and minimizing physical disruption of the sample. Scanning with an AFM at cryogenic temperatures has the potential to image frozen biomolecules at high resolution. We have constructed a force microscope capable of operating immersed in liquid n-pentane and have tested its performance at room temperature with carbon and metal-coated samples, and at 143° K with uncoated ferritin and purple membrane (PM).

A conduction-cooled stage for high-resolution Cryo-SEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1282-1283
Author(s):  
John G. Sheehan
Keyword(s):  
High Resolution ◽  
Liquid Nitrogen ◽  
Mechanical Stability ◽  
Cooling System ◽  
Cold Trap ◽  
Nitrogen Gas ◽  
Particulate Suspensions ◽  
Advantages And Disadvantages ◽  
Convection Cooling ◽  
Styrene Butadiene

The goal is to examine with high resolution cryo-SEM aqueous particulate suspensions used in coatings for printable paper. A metal-coating chamber for cryo-preparation of such suspensions was described previously. Here, a new conduction-cooling system for the stage and cold-trap in an SEM specimen chamber is described. Its advantages and disadvantages are compared to a convection-cooling system made by Hexland (model CT1000A) and its mechanical stability is demonstrated by examining a sample of styrene-butadiene latex.In recent high resolution cryo-SEM, some stages are cooled by conduction, others by convection. In the latter, heat is convected from the specimen stage by cold nitrogen gas from a liquid-nitrogen cooled evaporative heat exchanger. The advantage is the fast cooling: the Hexland CT1000A cools the stage from ambient temperature to 88 K in about 20 min. However it consumes huge amounts of liquid-nitrogen and nitrogen gas: about 1 ℓ/h of liquid-nitrogen and 400 gm/h of nitrogen gas. Its liquid-nitrogen vessel must be re-filled at least every 40 min.

Computer simulations for the TEM bend contour technique

1996 ◽  
Vol 54 ◽  
pp. 134-135
Author(s):  
Vladimir Yu. Kolosov ◽  
Anders R. Thölén
Keyword(s):  
Computer Simulations ◽  
Real Space ◽  
Advantages And Disadvantages ◽  
Short Overview ◽  
Diffraction Contrast ◽  
Beam Method ◽  
Convergent Beam ◽  
Contour Technique

In this paper we give a short overview of two TEM applications utilizing the extinction bend contour technique (BC) giving the advantages and disadvantages; especially we consider two areas in which the BC technique remains unique. Special attention is given to an approach including computer simulations of TEM micrographs.BC patterns are often observed in TEM studies but are rarely exploited in a serious way. However, this type of diffraction contrast was one of the first to be used for analysis of imperfections in crystalline foils, but since then only some groups have utilized the BC technique. The most extensive studies were performed by Steeds, Eades and colleagues. They were the first to demonstrate the unique possibilities of the BC method and named it real space crystallography, which developed later into the somewhat similar but more powerful convergent beam method. Maybe, due to the difficulties in analysis, BCs have seldom been used in TEM, and then mainly to visualize different imperfections and transformations.

Sign in / Sign up

Export Citation Format

Share Document