BACKGROUND Fractionated electrograms are used by some as targets for ablation in atrial and ventricular arrhythmias. Fractionation has been demonstrated to result when there is repetitive or asynchronous activation of separate groups of cells within the recording region of a mapping electrode(s). METHODS AND RESULTS Using a computer model, we generated tissue activation patterns with increasi...

abstract a study was conducted to evaluate the effect of incubation time, sewage sludge and clay content on the distribution of nickel and cadmium in different fractions of selected calcareous soils. to meet this purpose, an experiment with two different soils (4 and 30 percent caco3), two different textures (8 and 40 percent clay), two levels of nickel (0 and 100 mg.kg-1), two levels of cadmiu...

returning crop residues into the soil as a source of organic matter are an important source of copper and can play an important role in the soil fertility. in addition to the role of the organic matter in increasing the concentration of micronutrients in soil solution, attention should be also paid to the role of the kind and the quantity of the root’s exudates released in response to the incor...

A general method of automated multidimensional fractionation has been developed. Its basic ingredients are: (a) cascade fractionation, i.e., the sequential fractionation of components obtained from each chromatographic dimension on the same or a different dimension, (b) on-line acquisition and processing of data at each stage in the fractionation procedure, (c) a method for determining the begi...

A series of laboratory studies were conducted to increase understanding of stable carbon (C/C) and hydrogen (D/H) isotope fractionation arising from methanogenesis by moderately thermophilic acetateand hydrogen-consuming methanogens. Studies of the aceticlastic reaction were conducted with two closely related strains of Methanosaeta thermophila. Results demonstrate a carbon isotope fractionatio...