Powdery mildew caused by Erysiphe necator, is one of the most economically damaging diseases of grapevine throughout the world. This is the first molecular biology study on this fungus in Iran. The aims of the present study were (a) to analyse genetic diversity between isolates of E. necator fungus in four main grape production regions in Iran, i. e., Qazvin, Alamoot, Takestan and Shahriar and ...

Mutants defective in various steps of the sexual cycle have been isolated from homothallic strains of Schizosaccharomyces pombe by BRESCH, MULLER and EGEL (1968). These mutants include heterothallic h+ and hstrains. We have isolated additional h+ and hmutants from homothallic strains. Those mutants which are due to mutations in the mating-type region were analyzed in detail. Our results show th...

EEVE (1953, 1955,1961) has suggested that assortative mating of parents be used to obtain data for estimation of heritability by parent-offspring regression. The advantage of this technique over the standard random mating procedure is that the variance of midparent values is increased, thereby providing greater accuracy in the estimation of the regression coefficient. Possible bias introduced a...

This paper analyzes the dynamics of a new selection scheme based on altruistic cooperation between individuals. The scheme, which we refer to as cooperative selection, extends from tournament selection and imposes a stringent restriction on the mating chances of an individual during its lifespan: winning a tournament entails a depreciation of its fitness value. We show that altruism minimizes t...

The system of linearly coupled nonlinear Schrödinger equations is solved by a conservative difference scheme in complex arithmetic. The initial condition represents a superposition of two one-soliton solutions of linear polarizations. The head-on and takeover interaction of the solitons and their quasi-particle (QP) behavior is examined in conditions of rotational polarization and gain. We foun...

The use of rotational-echo double resonance NMR to measure distances from an observed tightly coupled cluster of 13C spins to a distant 15N, 31P, or 19F is practical if all homonuclear 13C-13C dipolar interactions are suppressed by multiple-pulse decoupling during heteronuclear dipolar evolution. This scheme is first calibrated by experiments performed on multiply labeled alanines and then appl...

The significance of the seismic rotational components have been overlooked in the seismic evaluation of structural behavior. As researchers have measured seismic components more accurately using sensitive rotational velocity sensor, it was observed that the magnitude of rotational components is considerable and could not be neglected. Hence, some parts of seismic damage or failure of structures...