GENETIC DETERMINATION OF HIGH MEIOTIC REVERSION FREQUENCIES IN ISOLEUCINE-VALINE 1 HOMOALLELIC CROSSES IN NEUROSPORA

1972 ◽  
Vol 14 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Howard T. Bausum
Keyword(s):  
Growth Rate ◽  
High Frequency ◽  
Chromosome Region ◽  
Genetic Determination ◽  
Reciprocal Crosses ◽  
Enhancing Factor ◽  
Mode Of Operation ◽  
Single Allele ◽  
Group 2

High frequency reversion in homo- and heteroallelic crosses of isoleucine-valine-1 (iv-1) group 2 alleles was reported previously. The genetic determination of homoallelic reversion in a single allele, Tiv 318, is reported here.The property of yielding prototrophs in test crosses underwent 2:2 segregation in tetrads and showed close linkage to spray (sp) and actidione-2 (act-2). Crosses of ordered segregants from a reverting lysine-1 (lys-1) iv × iv sp cross and of random spore isolates from six reverting lys-1 iv × iv act-2 crosses identified a disparity of origin of the pertinent chromosome region as an enhancing factor, but not a sine qua non of reversion. This region exists in at least three states such that a combination of two is effective. Direct involvement of outside markers was excluded. The cytogenetic nature and mode of operation of the enhancing factor are unknown.Prototroph frequency did not differ in reciprocal crosses, and the growth rate of revertants was unaffected by isoleucine and valine.

Magnetic Permeability and Relaxation Frequency in High Frequency Magnetic Materials.

2001 ◽  
Vol 674 ◽  
Author(s):  
M.I. Rosales ◽  
H. Montiel ◽  
R. Valenzuela
Keyword(s):  
High Frequency ◽  
Domain Walls ◽  
Magnetocrystalline Anisotropy ◽  
Low Frequency ◽  
Frequency Dispersion ◽  
Anisotropy Constant ◽  
Relaxation Frequency ◽  
Resonance Relaxation ◽  
Frequency Behavior

ABSTRACTAn investigation of the frequency behavior of polycrystalline ferrites is presented. It is shown that the low frequency dispersion (f < 10 MHz) of permeability is associated with the bulging of pinned domain walls, and has a mixed resonance-relaxation character, closer to the latter. It is also shown that there is a linear relationship between the magnetocrystalline anisotropy constant, K1, and the relaxation frequency. The slope of this correlation depends on the grain size. Such a relationship could allow the determination of this basic parameter from polycrystalline samples.

scholarly journals Relationship Between Root and Yield Related Morphological Characters in Pea (Pisum Sativum L.)

2014 ◽  
Vol 66 (1) ◽  
pp. 3-15
Author(s):  
Sylwia Ciaglo-Androsiuk
Keyword(s):  
Root System ◽  
Morphological Traits ◽  
Lateral Roots ◽  
Morphological Characters ◽  
Yield Potential ◽  
Cultivated Plants ◽  
Genetic Determination ◽  
Canonical Correlations ◽  
Effect On Yield

AbstractRelation between morphological traits of the root system and yield related traits is an important issue concerning efforts aiming at improving of ideotype of cultivated plants species, including pea. In this paper, to analyse the dependency between traits describing the root system morphology and yield potential, Person’s andSpearman's_correlations as well as canonical correlations were used.Root system was analyzed in 14 and 21 day-old seedlings growing in blotting-paper cylinders. Yield potential of pea was analysed in a field experiment. Results of Person’s and Spearman's_correlations revealed that number of lateral roots and lateral roots density were correlated witch yield related traits. Correlation between root length and shoot length was observed only for 14 day-old seedlings. The result of canonical correlations revealed that number of lateral roots and lateral roots density had the largest effect on yield related traits. This work highlights, that in order to improve the yield of pea it might become necessary to understand genetic determination of morphological traits of the root system, especially number of lateral roots.

Scattering of electromagnetic waves by hybrid waves in a two-electron-temperature plasma

1991 ◽  
Vol 46 (1) ◽  
pp. 99-106 ◽  
Author(s):  
S. K. Sharma ◽  
A. Sudarshan
Keyword(s):  
Growth Rate ◽  
Electron Temperature ◽  
High Frequency ◽  
Electromagnetic Waves ◽  
Low Frequency ◽  
Lower Hybrid ◽  
Stimulated Scattering ◽  
Coupled Modes ◽  
Temperature Plasma ◽  
Electrostatic Perturbation

In this paper, we use the hydrodynamic approach to study the stimulated scattering of high-frequency electromagnetic waves by a low-frequency electrostatic perturbation that is either an upper- or lower-hybrid wave in a two-electron-temperature plasma. Considering the four-wave interaction between a strong high-frequency pump and the low-frequency electrostatic perturbation (LHW or UHW), we obtain the dispersion relation for the scattered wave, which is then solved to obtain an explicit expression for the growth rate of the coupled modes. For a typical Q-machine plasma, results show that in both cases the growth rate increases with noh/noc. This is in contrast with the results of Guha & Asthana (1989), who predicted that, for scattering by a UHW perturbation, the growth rate should decrease with increasing noh/noc.

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