The lungs normally are ventilated with enough air to dilute the carbon dioxide produced by metabolism, so that the partial pressure of carbon dioxide (Pco,) in the alveoli is kept remarkably close to 40 mm. Hg. It is the alveolar ventilation and not the total amount of air going in or out of the mouth (or 'minute-volume') that determines the Pco2 because a varying proportion of the total ventil...

Ocean acidification severely affects bivalves, especially their larval stages. Consequently, the fate of this ecologically and economically important group depends on the capacity and rate of evolutionary adaptation to altered ocean carbonate chemistry. We document successful settlement of wild mussel larvae (Mytilus edulis) in a periodically CO2-enriched habitat. The larval fitness of the popu...

[1] A theory for the ocean-atmosphere partitioning of anthropogenic carbon dioxide on centennial timescales is presented. The partial pressure of atmospheric CO2 (PCO2) is related to the external CO2 input (DSC) at air-sea equilibrium by: PCO2 = 280 ppm exp(DSC/[IA + IO/R]), where IA, IO, and R are the pre-industrial values of the atmospheric CO2 inventory, the oceanic dissolved inorganic carbo...

Early life history stages of marine organisms are generally thought to be more sensitive to environmental stress than adults. Although most marine invertebrates are broadcast spawners, some species are brooders and/or protect their embryos in egg or capsules. Brooding and encapsulation strategies are typically assumed to confer greater safety and protection to embryos, although little is known ...

Global climate change includes rising temperatures and increased pCO2 concentrations in the ocean, with potential deleterious impacts on marine organisms. In this case study we conducted a four-week climate change incubation experiment, and tested the independent and combined effects of increased temperature and partial pressure of carbon dioxide (pCO2), on the microbiomes of a foundation speci...

Sampling arterialized earlobe blood is thought to be easier and less painful than direct arterial puncture, and to allow measurement of blood gas values during exercise without the need to insert an arterial cannula. However, arterialized earlobe oxygen tension (PO2) often underestimates arterial PO2 at rest, and is not fully validated during exercise. We have therefore conducted a prospective ...

background: substitution of arterial with venous blood samples to estimate blood gas status is highly preferable due to practical and safety concerns. numerous studies support the substitution of arterial by venous blood samples, reporting strong correlations between arterial and venous values. this study further investigated the predictive ability of venous blood samples for arterial acid-base...

During summer, upwelled water with elevated CO2 partial pressure (pCO2) and nutrients outcrops over the Oregon (OR) inner shelf. As this water transits across the shelf, high rates of primary production fueled by the upwelled nutrients results in net atmospheric CO2 drawdown. Upwelled source-waters typically have pCO2 approaching 1000 matm that is then reduced to 200 matm. For almost the entire...

Anthropogenic climate change compromises reef growth as a result of increasing temperatures and ocean acidification. Scleractinian corals vary in their sensitivity to these variables, suggesting species composition will influence how reef communities respond to future climate change. Because data are lacking for many species, most studies that model future reef growth rely on uniform scleractin...

Homeostatic regulation of the partial pressure of CO2 (PCO2) is vital for life. Sensing of pH has been proposed as a sufficient proxy for determination of PCO2 and direct CO2-sensing largely discounted. Here we show that connexin 26 (Cx26) hemichannels, causally linked to respiratory chemosensitivity, are directly modulated by CO2. A 'carbamylation motif', present in CO2-sensitive connexins (Cx...