Atomic force microscopy analysis of DNA extracted from the vegetative cells and the viable, but nonculturable, cells of two mycoplasmas (Acholeplasma laidlawii PG8 and Mycoplasma hominis PG37)

This article reports on a study of some characteristics of DNA extracted from the vegetative and viable, but nonculturable (VBNC), cells of two mycoplasma species (Acholeplasma laidlawii PG8 and Mycoplasma hominis PG37) using atomic force microscopy (AFM). DNA images were obtained by operating the AFM microscope in the tapping mode. It was found that DNA from the VBNC forms of M. hominis PG37 has decreased sizes (height: 0.177 ± 0.026 nm vs. 0.391 ± 0.041 nm for the vegetative forms, and width: 1.92 ± 0.099 vs. 2.17 ± 0.156 nm for the vegetative forms) in comparison to DNA from the vegetative forms of the mycoplasma. In the case of DNA from the A. laidlawii PG8 VBNC forms, we detected a decrease in width (1.506 ± 0.076 nm vs. 1.898 ± 0.117 nm for the vegetative forms), but an increase in height (0.641 ± 0.068 nm vs. 0.255 ± 0.010 nm for the vegetative forms) of the molecule. Analyzing the obtained results, one can speculate on some similarities in the physical-chemical properties of DNA from M. hominis PG37 and M. gallisepticum S6. In turn, this implies some general mechanisms of adaptation to a severe environment. ©2010 with author. Published by TheScientificWorld

Enhancement of the electric dipole moment of the electron in the YbF molecule

We calculate an effective electric field on the unpaired electron in the YbF molecule. This field determines sensitivity of the molecular experiment to the electric dipole moment of the electron. We use experimental value of the spin-doubling constant to estimate the admixture of the configuration with the hole in the 4f-shell of Ytterbium to the ground state of the molecule. This admixture reduces the field by 7%. Our value for the effictive field is 5.1 a.u. = 2.5 10^{10} V/cm.Comment: 5 pages, LATEX, uses revtex.st

10He low-lying states structure uncovered by correlations

The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He reaction was found at about $2.1\pm0.2$ MeV (\Gamma ~ 2 MeV) above the three-body 8He+n+n breakup threshold. Angular correlations observed for 10He decay products show prominent interference patterns allowing to draw conclusions about the structure of low-energy excited states. We interpret the observed correlations as a coherent superposition of the broad 1- state having a maximum at energy 4-6 MeV and the 2+ state above 6 MeV, setting both on top of the 0+ state "tail". This anomalous level ordering indicates that the breakdown of the N=8 shell known in 12Be thus extends also to the 10He system.Comment: 5 pages, 5 figure