Direct and indirect effects of warming are increasingly modifying the carbon-rich vegetation and soils of the Arctic tundra, with important implications for the terrestrial carbon cycle. Understanding the biological and environmental influences on the processes that regulate foliar carbon cycling in tundra species is essential for predicting the future terrestrial carbon balance in this region....

Gas exchange is governed by the combined action of oxygen consumption and carbon dioxide production, and the transport of these gasses by diffusion. The diffusion component is formally neglected and implicitly incorporated in respiration and fermentation parameters of the current Michealis-Menten-based respiration models. The aim was to extend existing modelling approaches by including a diffus...

The space-filling fractal network in the human lung creates a remarkable distribution system for gas exchange. Landmark studies have illuminated how the fractal network guarantees minimum energy dissipation, slows air down with minimum hardware, maximizes the gas- exchange surface area, and creates respiratory flexibility between rest and exercise. In this paper, we investigate how the fractal ...

An accurate mathematical model of transmucosal gas exchange is prerequisite to understanding middle ear (ME) physiology. Current models require experimentally measured gas species time constants for all extant conditions as input parameters. However, studies on pulmonary gas exchange have shown that a morphometric model that incorporates more fundamental physiochemical and anatomic parameters a...

photosynthetic characteristics and induction of crassulacean acid metabolism (cam) by drought stress were investigated in sedum album, sedum stoloniferum and rosularia elymaitica from crassulaceae. titratable acidity, malate content, phosphoenolpyruvate carboxylase (pepc) activity and gas exchange parameters were determined in plants at the end and beginning of the photoperiod. results showed t...

The importance of metabolic rate and/or spiracle modulation for saving respiratory water is contentious. One major explanation for gas exchange pattern variation in terrestrial insects is to effect a respiratory water loss (RWL) saving. To test this, we measured the rates of CO2 and H2O release ( and , respectively) in a previously unstudied, mesic cockroach, Aptera fusca, and compared gas exch...