Polar Oceans are natural CO2 sinks because of the enhanced solubility of CO2 in cold water. The Arctic Ocean is at additional risk of accelerated ocean acidification (OA) because of freshwater inputs from sea ice and rivers, which influence the carbonate system. Winter conditions in the Arctic are of interest because of both cold temperatures and limited CO2 venting to the atmosphere when sea i...

Elevated CO2 and nitrogen (N) addition directly affect plant productivity and the mechanisms that allow tidal marshes to maintain a constant elevation relative to sea level, but it remains unknown how these global change drivers modify marsh plant response to sea level rise. Here we manipulated factorial combinations of CO2 concentration (two levels), N availability (two levels) and relative se...

It has been reported that injection of somatostatin into the brain-stem will lead to apnoea in animals. The aim of this study was to determine whether peripheral administration of octreotide, an analogue of somatostatin, could influence the control of breathing. We measured the tidal volume, respiratory rate and ventilatory response to CO2, before and after the intravenous injection of two dose...

Introduction Functional connectivity analysis has been used to map several consistent resting state networks by exploiting coherent low-frequency fluctuations in the BOLD signal. The assumption in most of the fMRI literature is that these correlated fluctuations are neuronal in origin. Others sources of low-frequency fluctuations exist in fMRI data that are unrelated to neuronal activity. These...

In order to estimate to what extent the stimulatory action of CO2 on ventilation is mediated by the formation of H+, we studied effects on the temporal profile of ventilatory response to CO2 of carbonic anhydrase (CA) inhibition with acetazolamide in the halothane anesthetized spontaneously breathing rat. Since hydration reaction of CO2 yielding H+ is delayed by CA inhibition, the time courses ...

In this study, we investigated possible separate effects of H+ ions and CO2 on hypoxic sensitivity in humans. We also examined whether hypoxic sensitivity, conventionally defined as the ratio of (hypoxic - normoxic) ventilation over (hypoxic - normoxic) Hb oxygen saturation can also be estimated by taking the ratio (hypoxic - normoxic) ventilation over (logPa(O2) hypoxia - logPa(O2) normoxia), ...

Single fibre and "integrated" phrenic nerve activity was recorded in anaesthetized spontaneously breathing rabbits, during experimentally induced lung oedema. Tidal volume, blood pressure, end-tidal CO2, were monitored. In oedema the number of impulses in each volley slightly decreased while the discharge frequency was increased relatively to control values. The latter effect was due to the inc...

Objective: This study is to explore the impact of different pressure of artificial pneumothorax on surgical exposure and patients’ respiratory and circulation in thoracic esophageal laparoscopic surgery. Method: The 60 esophageal cancer patients were randomly divided into 2 groups: the experiment group (single lumen endotracheal intubation with artificial pneumothorax pressure of 9 mmHg) and th...

The purpose of this study was to evaluate algorithms for estimating O2 and CO2 transfer at the pulmonary capillaries by use of a nine-compartment tidally ventilated lung model that incorporated inhomogeneities in ventilation-to-volume and ventilation-to-perfusion ratios. Breath-to-breath O2 and CO2 exchange at the capillary level and at the mouth were simulated by using realistic cyclical breat...

Materials and methods: 77 consecutive patients underwent t-LRP. The last 38 patients treated using Thermoflator (group A) have been compared with the first 39 patients treated using Airseal (group B). Mean intrabdominal pressure was mantained at 12 mmHg in all patients. Baseline tidal, minute ventilation and positive end expiratory pressure (PEEP) were set at 8 ml/Kg, 10 breaths/minute and 5 cm...