Air-Sea Gas Exchange and Carbon Dioxide

1993 ◽  
pp. 397-411 ◽  
Author(s):  
Andrew Watson
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange

Eddy covariance flux measurements of momentum, heat and carbon dioxide in Hudson Bay at the onset of sea ice melt 

2021 ◽  
Author(s):  
Richard Sims ◽  
Brian Butterworth ◽  
Tim Papakyriakou ◽  
Mohamed Ahmed ◽  
Brent Else
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Sea Ice ◽  
Eddy Covariance ◽  
Open Water ◽  
The Arctic ◽  
Gas Transfer ◽  
Hudson Bay ◽  
Flux Measurements ◽  
Ice Fraction

<p>Remoteness and tough conditions have made the Arctic Ocean historically difficult to access; until recently this has resulted in an undersampling of trace gas and gas exchange measurements. The seasonal cycle of sea ice completely transforms the air sea interface and the dynamics of gas exchange. To make estimates of gas exchange in the presence of sea ice, sea ice fraction is frequently used to scale open water gas transfer parametrisations. It remains unclear whether this scaling is appropriate for all sea ice regions. Ship based eddy covariance measurements were made in Hudson Bay during the summer of 2018 from the icebreaker CCGS Amundsen. We will present fluxes of carbon dioxide (CO<sub>2</sub>), heat and momentum and will show how they change around the Hudson Bay polynya under varying sea ice conditions. We will explore how these fluxes change with wind speed and sea ice fraction. As freshwater stratification was encountered during the cruise, we will compare our measurements with other recent eddy covariance flux measurements made from icebreakers and also will compare our turbulent CO<sub>2 </sub>fluxes with bulk fluxes calculated using underway and surface bottle pCO<sub>2</sub> data. </p><p> </p>

Respiration in man during metabolic alkalosis

1962 ◽  
Vol 17 (1) ◽  
pp. 33-37 ◽  
Author(s):  
Daniel J. Stone
Keyword(s):  
Carbon Dioxide ◽  
Steady State ◽  
Lung Function ◽  
Gas Exchange ◽  
Metabolic Alkalosis ◽  
Time Lag ◽  
Respiratory Compensation ◽  
Arterial Ph ◽  
Oral Sodium ◽  
Ventilation Response

A steady state metabolic alkalosis was induced in two subjects over a period of several days utilizing oral sodium bicarbonate in dosages of 50 g/day. The purpose of inducing steady state metabolic alkalosis was to study the effects of such a state on the respiratory center responses to inspired gas mixtures, containing carbon dioxide, and to contrast these results with the control studies. The experiment was so designed that the arterial pH in both subjects tended to return toward normal in the presence of significant increases in blood bicarbonate. Repeated study of ventilation responses with room air and 4% and 6% carbon dioxide in inspired air revealed a definite and significant decrease in ventilation response to carbon dioxide during the periods of steady state alkalosis as compared to the control periods. Normal responses returned after some time lag. A consistent rise in paCOCO2 occurred with alkalosis, thus demonstrating respiratory compensation. In neither subject was total lung function or gas exchange affected by the alkalosis. The experiment was confirmed on several occasions with reproducible results. Note: (With the Research Assistance of Mary Di Lieto) Submitted on May 22, 1961

Inspiratory Speech as a Management Option for Spastic Dysphonia

1992 ◽  
Vol 101 (5) ◽  
pp. 375-382 ◽  
Author(s):  
Gordon A. Harrison ◽  
Richard H. Troughear ◽  
Pamela J. Davis ◽  
Alison L. Winkworth
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Voice Quality ◽  
Management Option ◽  
Communication Problems ◽  
Partial Pressures ◽  
The Subject ◽  
And Control ◽  
Laryngeal Resistance

A case study is reported of a subject who has used inspiratory speech (IS) for 6 years as a means of overcoming the communication problems of long-standing adductor spastic dysphonia (ASD). The subject was studied to confirm his use of IS, determine the mechanisms of its production, investigate its effects on ventilatory gas exchange, and confirm that it was perceptually preferable to ASD expiratory speech (ES). Results showed that the production and control of a high laryngeal resistance to airflow were necessary for usable IS. Voice quality was quantitatively and perceptually poor; however, the improved fluency and absence of phonatory spasm made IS the preferred speaking mode for both the listener and the speaker. Transcutaneous measurements of the partial pressures of oxygen and carbon dioxide in the subject's blood were made during extended speaking periods. These measurements indicated that ventilation was unchanged during IS, and that ventilation during ES was similar to the “hyperventilation” state of normal speakers. The reasons for the absence of phonatory spasm during IS are discussed, and the possibility of its use as a noninvasive management option for other ASD sufferers is addressed.

Cardiac output determination via reduced gas exchange of carbon dioxide within an existing ventilator

2001 ◽  
Vol 18 (Supplement 22) ◽  
pp. 35
Author(s):  
I. R. A. M. ◽  
M. zur Borg ◽  
H. van der Zee ◽  
G. van Dijk ◽  
J. Klein
Keyword(s):  
Carbon Dioxide ◽  
Cardiac Output ◽  
Gas Exchange ◽  
Cardiac Output Determination

scholarly journals Second-generation laryngeal mask airway as an alternative to endotracheal tube during prolonged laparoscopic abdominal surgery: a comparative analysis of intraoperative gas exchanges

2021 ◽  
Author(s):  
S Park ◽  
JE Lee ◽  
GS Choi ◽  
JM Kim ◽  
JS Ko ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Laryngeal Mask Airway ◽  
Abdominal Surgery ◽  
Partial Pressure ◽  
Endotracheal Tube ◽  
Second Generation ◽  
Laryngeal Mask ◽  
Arterial Partial Pressure ◽  
Prolonged Surgery

Introduction: Despite several advantages over endotracheal tube (ETT), laryngeal mask airway (LMA), which is used in emergencies under difficult airway maintenance conditions, is rarely utilized in prolonged surgery. We compared the variables representing intraoperative gas exchange with second-generation LMA and ETT during prolonged laparoscopic abdominal surgery. Methods: Prolonged surgery was defined as a surgery lasting more than 2 h. In total, 394 patients who underwent laparoscopic liver resection via either second-generation LMA or ETT were retrospectively analysed. Parameters including end-tidal pressure of carbon dioxide (ETCO2), tidal volume (TV), respiratory rate (RR), peak inspiratory pressure (PIP), arterial partial pressure of carbon dioxide (PaCO2), pH, and ratio of arterial partial pressure of oxygen to fractional inspired oxygen (PFR) during surgery were compared between the two groups. In addition, the incidence of postoperative pulmonary complications (PPC) including pulmonary aspiration was also compared. Results: The values of ETCO2, TV, RR and PIP during pneumoperitoneum were comparable between the two groups. Although PaCO2 at 2 h after induction was higher in patients with LMA (40.5 vs. 38.5 mmHg, p < 0.001), the pH and PFR values of the two groups were comparable. The incidence of PPC was not different. Conclusion: During prolonged laparoscopic abdominal surgery, the second-generation LMA facilitates adequate intraoperative gas exchange and represents an alternative to ETT.

scholarly journals The Effect of NAA and BA on Carbon Dioxide Assimilation by Shoot Leaves of Spur-type `Delicious' and `Empire' Apple Trees

1997 ◽  
Vol 122 (6) ◽  
pp. 837-840 ◽  
Author(s):  
Matej Stopar ◽  
Brent L. Black ◽  
Martin J. Bukovac
Keyword(s):  
Carbon Dioxide ◽  
Acetic Acid ◽  
Gas Exchange ◽  
Malus Domestica ◽  
Assimilation Rate ◽  
Carbon Dioxide Assimilation ◽  
Gas Exchange Parameters ◽  
Apple Trees ◽  
Fruit Thinning ◽  
Exchange Parameters

The effects of NAA, BA, or Accel on CO2 assimilation of shoot leaves of mature bearing Redchief `Delicious' and `Empire' apple (Malus ×domestica Borkh.) trees were evaluated over two seasons. BA at 50 mg·L-1 did not significantly affect any of the gas-exchange parameters measured. NAA (15 mg·L-1) consistently suppressed CO2 assimilation rate (from ≈10% to 24% below that of the control). This suppression was NAA-concentration dependent, continued for >15 days after treatment, and was completely overcome in `Empire', but only partially or not at all in `Delicious' when BA was combined with NAA. These results are discussed in relation to fruit thinning and NAA-induced inhibition of fruit growth in spur-type `Delicious'. Chemical names used: 2-(1-napthyl) acetic acid (NAA); N-(phenyl)-1H-purine-6-amine (BA); BA + gibberellin A (GA)4+7 (Accel).

scholarly journals Ternary effects on the gas exchange of isotopologues of carbon dioxide

2012 ◽  
Vol 35 (7) ◽  
pp. 1221-1231 ◽  
Author(s):  
GRAHAM D. FARQUHAR ◽  
LUCAS A. CERNUSAK
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange
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