Thermodynamic measurements are required to confirm whether cloned transport-associated proteins in a membrane truly constitute a functional transport system. Symport or antiport, catalyzed by native systems or by cloned proteins in membranes, can lead to steady-state intracellular accumulation of solute when the electrochemical potentials of activator ion and solute are energetically coupled. S...

Ion bombardment provides an opportunity to study basic properties of intrinsic defects in materials since the radiation-induced disorder accumulation depends on balance between defect generation and migration rates. In particular, variation such parameters as irradiation temperature ion flux, known literature dose-rate effect, interconnects macroscopically measured lattice with barrier dominati...

Grafting is a centuries-old technique used in plants to obtain economic benefits. Grafting increases nutrient uptake and utilization efficiency in a number of plant species, including fruits, vegetables, and ornamentals. Selected rootstocks of the same species or close relatives are utilized in grafting. Rootstocks absorb more water and ions than self-rooted plants and transport these water and...

Understanding the mechanism of stomatal opening in leaves is important because stomata are the avenues for CO2 and H,O diffusion. Stomata in most species open in the light when the guard cells that encompass the pores take up water and increase in turgor relative to adjacent epidermal cells (1). Thus stomatal opening is likely an osmotic plhenomenon that depends upon the accumulation of solute ...

The influenza A/fowl plague virus/Rostock/34 hemagglutinin (HA), which is cleaved intracellularly and has a high pH threshold (pH 5.9) for undergoing its conformational change to the low-pH form, was expressed from cDNA in CV-1 and HeLa T4 cells in the absence of other influenza virus proteins. It was found, by biochemical assays, that the majority of the HA molecules were in a form indistingui...

A bsttract. In contrast to intact etiolated pea seedling tissue (Pisum sativum L.), excised segments immersed in a complete nutrient solution show marked increases in ion content, largely of K+ and NO.-, over a 72-hour period. During this time there is increase in cell electropotential difference, PD. During the initial 6 to 8 hours there is a lag in ion uptake; cell PD, however, increases rapi...

An oligotriarylamine (OTA) unit, a Ru(bpy)3(2+) photosensitizer moiety (Ru), and an anthraquinone (AQ) entity were combined to a molecular dyad (Ru-OTA) and a molecular triad (AQ-Ru-OTA). Pulsed laser excitation at 532 nm led to the formation of charge-separated states of the type Ru(-)-OTA(+) and AQ(-)-Ru-OTA(+) with lifetimes of ≤10 ns and 2.4 μs, respectively, in de-aerated CH3CN at 25 °C. U...

The effects of monovalent cations on the active calcium-accumulating ability of cardiac sarcoplasmic reticulum were assessed. Grana prepared in an ion-free system accumulated calcium when ATP and Mg(++) were present. Sodium ion and to a lesser extent lithium but not K(+) reduced the amount of calcium taken up. The reduction of calcium binding by Na(+) is not due to inhibition of uptake but to a...

An ion beam cooler and buncher has been developed for the manipulation of radioactive ion beams. The gas-filled linear radiofrequency ion trap system is installed at the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Its purpose is to accumulate the 60-keV continuous ISOLDE ion beam with high efficiency and to convert it into low-energy low-emittance ion pulses. The efficiency was foun...