After osmotic perturbation, the red blood cells of Amphiuma exhibited a volume-regulatory response that returned cell volume back to or toward control values. After osmotic swelling, cell-volume regulation (regulatory volume decrease; RVD) resulted from net cellular loss of K, Cl, and osmotically obliged H2O. In contrast, the volume-regulatory response to osmotic shrinkage (regulatory volume in...

Eddy correlation measurements of mass and energy were made simultaneously over a closed wheat and an open corn crop. This combination of crops, differing in canopy coverage and stomatal physiology, facilitated an investigation on how surface and environmental variables control the partitioning of net radiation into sensible, latent and soil heat exchange. Contrasts in canopy closure had a minor...

The closed chamber technique is widely used to measure the exchange of methane (CH4) and carbon dioxide (CO2) from terrestrial ecosystems. There is, however, large uncertainty about which model should be used to calculate the gas flux from the measured gas concentrations. Due to experimental uncertainties the robust ::::: simple linear regression model (first order polynomial) is often applied,...

Page, Sarah, Michael Salem, and Maren R. Laughlin. Intracellular Mg21 regulates ADP phosphorylation and adenine nucleotide synthesis in human erythrocytes. Am. J. Physiol. 274 (Endocrinol. Metab. 37): E920–E927, 1998.— 13Cand 31P-NMR were used in methylene blue-treated human erythrocytes to determine the dependence on intracellular Mg21 concentration ([Mg]i) of the pentose phosphate pathway (PP...

To evaluate the effects of O3 on the net photosynthetic rate in flag leaves of rice (Oryza sativa L.) based on stomatal O3 flux and reactive oxygen species (ROS) scavenging enzyme activities, the Japanese rice cultivar Koshihikari was exposed to O3 for 1 month after heading in O3-exposure chambers. During the exposure period, rice plants were exposed to charcoal-filtered air or O3 at 60 or 100 ...

We investigate directed thermal heat flux across one-dimensional homogenous nonlinear lattices when no net thermal bias is present on average. A nonlinear lattice of Fermi-Pasta-Ulam-type or Lennard-Jones-type system is connected at both ends to thermal baths which are held at the same temperature on temporal average. We study two different modulations of the heat bath temperatures, namely: (i)...

Na transport and electrical properties of Necturus renal proximal tubules were analyzed, in vivo, by a voltage clamp method which utilizes an axial electrode in the tubule lumen for passage of current and simultaneous determination of net fluid (or Na) flux by the split droplet method. When the average spontaneous transepithelial potential difference of -8 mv (lumen negative) was reduced to zer...

PURPOSE The retinal pigment epithelium (RPE) expresses aquaporin-1 (AQP1) and components of the natriuretic peptide signaling pathway. We hypothesized that stimulation of the natriuretic signaling pathway in RPE with atrial natriuretic peptide (ANP) and with membrane-permeable analogs of cGMP would induce a net apical-to-basal transport of fluid. METHODS The hypothesis was tested using human ...