River-dominated continental shelf environments are active sites of air-sea CO2 exchange. We conducted 13 cruises in the northern Gulf of Mexico, a region strongly influenced by fresh water and nutrients delivered from the Mississippi and Atchafalaya River system. The sea surface partial pressure of carbon dioxide (pCO2) was measured, and the air-sea CO2 flux was calculated. Results show that CO...

Quantifying the amount of carbon dioxide (CO2) in seawater is an essential component of ocean acidification research; however, equipment for measuring CO2 directly can be costly and involve complex, bulky apparatus. Consequently, other parameters of the carbonate system, such as pH and total alkalinity (AT), are often measured and used to calculate the partial pressure of CO2 (pCO2) in seawater...

The Haldane effect coefficient in vivo and arterial-venous O2 content difference [a-v)Co2) are, more or less, influenced by the contact time (tc), PO2 and PCO2 differences between venous blood and alveolar air. To increase the accuracy of the (a-v)CO2 and the cardiac output measured by means of the rebreathing technique, factors to correct the Haldane effect (F(H] and (a-v)CO2 (F(avCO2] were ob...

Address for Correspondence:Masaji Mochizuki, Minami-11, Nishi-20, 4-23 Chuo-Ku, Sapporo 064-0811, Japan The bicarbonate concentration in plasma , [HCO3], has a PCO2-dependent component, [HCO3]*, and a metabolic component, [HCO3]. The [HCO3]* in elderly patients and volunteers was expressed by an exponential function of PCO2 obtained by analysis of the venous-arterial (a-v) difference in [HCO3]....

The relationship between the plasma concentration of morphine and morphine-induced changes in ventilation and the ventilatory response to carbon dioxide was studied in 17 healthy adults undergoing elective surgery under general anaesthesia. Each subject was given morphine sulphate 0.15 mg kg-1 i.m.; ventilation (Ve), end-tidal PCO2(PE'CO2), mixed venous PCO2(PVCO2) and ventilatory response to c...

Breath holding was used as the basis of a simple test of respiratory chemosensitivity. Breath holding was begun at selected degrees of hypercapnia produced by CO2 rebreathing. In 16 healthy control subjects there was a linear regression of the log of breath-holding time on the PCO2 at the start of breath holding. Breath-holding time (BHT) and the slope of a log BHT/Pco2 plot were closely correl...

To determine the relationship between acid-base findings, such as pH, pCO2, and serum lactate levels, obtained immediately after starting cardiopulmonary resuscitation and the return of spontaneous circulation (ROSC).A prospective observational study of adult, nontraumatic out-of-hospital cardiac arrest (OHCA) patients was conducted at an urban academic teaching institution between April 1, 201...

Metabolic rate determines the physiological and life-history performances of ectotherms. Thus, the extent to which such rates are sensitive and plastic to environmental perturbation is central to an organism's ability to function in a changing environment. Little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms exposed to elevated pCO2. Cons...

Increasing atmospheric CO2 levels are driving changes in the seawater carbonate system, resulting in higher pCO2 and reduced pH (ocean acidification). Many studies on marine organisms have focused on short-term physiological responses to increased pCO2, and few on slow-growing polar organisms with a relative low adaptation potential. In order to recognize the consequences of climate change in b...

Future climate change is predicted to alter the physical characteristics of oceans and estuaries, including pH, temperature, oxygen, and salinity. Investigating how species react to the influence of such multiple stressors is crucial for assessing how future environmental change will alter marine ecosystems. The timing of multiple stressors can also be important, since in some cases stressors a...