High-frequency, paired measurements of the partial pressure CO2 (pCO2) and dissolved O2 were combined with organic matter (DOM) characterization to investigate diurnal (7:00–19:00) seasonal variations in dynamics lower Ganges River. Diurnal pCO2 shifted seasonally, concurring changes DOM optical properties, biodegradable DOM, departures from atmospheric equilibrium (ΔO2). Increased flux (FCO2) ...

The performance of an infra-red analyser (Beckman LB-2) in sampling alveolar gas at ventilatory frequencies and volumes occuring in the human neonate has been examined. The optimum sampling flow rate was found to be 300 ml/min; at this flow the 90% response time of the analyser-catheter system was 140 ms. Correlation of estimated alveolar PCO2 and arterial PCO2 was performed in the rabbit which...

Increased atmospheric CO2 concentrations lead to decreased pH and carbonate availability in the ocean (Ocean Acidification, OA). Carbon dioxide seeps serve as ‘windows into the future’ to study the ability of marine invertebrates to acclimatise to OA. We studied benthic foraminifera in sediments from shallow volcanic CO2 seeps in Papua NewGuinea. Conditions follow a gradient from present day pH...

Low pO2 values have been measured in the perivitelline fluids (PVF) of marine animal eggs on several occasions, especially towards the end of development, when embryonic oxygen consumption is at its peak and the egg case acts as a massive barrier to diffusion. Several authors have therefore suggested that oxygen availability is the key factor leading to hatching. However, there have been no mea...

BACKGROUND The objective of this study was to examine the correlation between arterial blood gas (ABG) and peripheral venous blood gas (VBG) samples for all commonly used parameters in patients admitted to a medical intensive care unit (ICU). METHODS A single-center, prospective trial was carried out in a medical ICU in order to determine the level of correlation of ABG and peripheral VBG mea...

Global climate change involves an increase in oceanic CO2 concentrations as well as thermal stratification of the water column, thereby reducing nutrient supply from deep to surface waters. Changes in inorganic carbon (C) or nitrogen (N) availability have been shown to affect marine primary production, yet little is known about their interactive effects. To test for these effects, we conducted ...

Elevated pCO2 may promote phytoplankton growth, and potentially alleviate carbon limitation during dense blooms. Under nitrogen-limited conditions, elevated pCO2 may furthermore alter the phytoplankton carbon-nitrogen (C:N) balance and thereby the synthesis of secondary metabolites, such as cyanobacterial toxins. A common group of these toxins are the microcystins, with variants that differ not...

The Arctic Ocean already experiences areas of low pH and high CO2, and it is expected to be most rapidly affected by future ocean acidification (OA). Copepods comprise the dominant Arctic zooplankton; hence, their responses to OA have important implications for Arctic ecosystems, yet there is little data on their current under-ice winter ecology on which to base future monitoring or make predic...

Objectives: This pilot study aimed to evaluate the feasibility and potential benefits of a novel biofeedback breathing training for achieving sustained increases in pCO2 levels. Methods: Twelve asthma patients were randomly assigned to an immediate 4-week treatment group or waiting list control. Patients were instructed to modify their respiration in order to change levels of end-tidal pCO2 usi...

[1] Several recent papers have demonstrated a decrease in atmospheric pCO2 resulting from barriers to communication between the deep sea and the atmosphere in the Southern Ocean. Stephens and Keeling [2000] decreased pCO2 by increasing Antarctic sea ice in a seven-box model of the world ocean, and Toggweiler [1999] showed a similar response to Southern Ocean stratification. In box models the pC...