Quark-Antiquark Potential and Generalized Borel Transform

The heavy quark potential and particularly the one proposed by Richardson to incorporate both asymptotic freedom and linear confinement is analyzed in terms of a generalized Borel Transform recently proposed. We were able to obtain, in the range of physical interest, an approximate analytical expression for the potential in coordinate space valid even for intermediate distances. The deviation between our approximate potential and the numerical evaluation of the Richardson's one is much smaller than $\Lambda$ of QCD. The $c\overline{c}$ and $b\overline{b}$ quarkonia energy levels agree reasonably well with experimental data for $c$ and $b$ masses in good agreement with the values obtained from experiments.Comment: 9 pages, 3 Tabl

One-loop vacuum amplitude for D-branes in constant electromagnetic field

Following Polchinski's approach we calculate the one-loop vacuum amplitude for two parallel D-branes connected by open bosonic (neutral or charged)string in a constant uniform electromagnetic (EM) field. For neutral string, external EM field contribution appears as multiplier (Born-Infeld type action) of vacuum amplitude without external EM field. Hence,it gives the alternative way to see the inducing of Born-Infeld type action for description of D-branes. For charged string the situation is more complicated, it may indicate the necessity to modify the induced D-branes action in this case.Comment: Latex file, 9page

BIOSOCIAL FACTORS AND PSYCHOVEGETATIVE PECULIARITIES IN FORMATION OF ADAPTATION ABNORMALITIES IN CHILDREN WITH GROWTH RETARDATION

110 children aged 7-16 with growth retardation have been under the study. Children with different clinical variants of growth retardation are characterized by individual clinical psychophysiological peculiarities. The cause-effect relation of biosocial factors, psychovegetative changes and high morbidity rate of children with growth retardation established in the research point out to their adaptation abnormalities, that require a differentiated approach to the development of rehabilitation programs