[en] Photoelectric data in the uvby system have been obtained for 367 southern stars of the Hipparcos Input Catalogue. Most of the stars are F and G main sequence and fall in the magnitude range 9< V<10

[en] A kinematic model is developed based on a dynamical model of stellar population synthesis. The model predictions are compared with two proper motion catalogues. (author). 2 figs., 15 refs

[en] In previous studies we have observed that auxotrophic mutants of yeast were much more sensitive to quaternary ammonium salts than the corresponding isogenic wild type strains. The super sensitivity of the auxotrophs seems to be a characteristic feature of yeast and yeast-like microorganisms: the level of sensitivity of the quaternary ammonium salts of the bacterial auxotrophs and their original prototrophic forms appeared to be the same. The super sensitivity of yeast auxotrophs disappeared on minimal media with ammonium as a nitrogen source. In this report there are presented the data indicating that enrichment of the minimal medium with arginine restores the super sensitivity of auxotrophic yeast mutants to the quaternary ammonium salts. The results of amino-acid transport into the auxotrophic yeast cells treated with a quaternary ammonium salt in the presence and absence of arginine are given. A working hypothesis of the mechanism of these salts action as a specific inhibition of nutrient transport is discussed. (author). 19 refs, 3 figs, 8 figs

[en] The model for deducing the local value of galactocentric gradient of the velocity dispersion is based on the local distribution of orbital eccentricity e, mean orbital radius ω-bar and the velocity perpendicular to the galactic plane. This is applied to samples of the Gliese's catalogue delimited by stars of F, G and K spectral types. For the galactic radial gradient of velocity dispersion the value of -0.2 kp/c is obtained, which is compatible with the Toomre's local stability criterion. (author). 4 figs., 2 tabs., 12 refs

[en] We present a new methodology that enables a significant sensitivity improvement for transverse magneto-optical Kerr effect (T-MOKE) detection. For this purpose, we developed a novel measurement scheme, in which the polarization detection conditions are changed during the measurement sequence in a pre-defined way. An analytical expression of the associated T-MOKE signal pattern was derived, which allowed us to analyze and classify our experimental data in a straightforward way. Furthermore, this new measurement approach enables the identification of noise and false background signals that might be generated by the sample under investigation, the environment or the detection system itself and it provides a pathway to unambiguously separate all these effects from true T-MOKE signals. These capabilities significantly increase the sensitivity and robustness of T-MOKE detection. The method enabled us to measure magneto-optical signals for samples that are paramagnetic at room temperature or exhibit really small magneto-optical responses, even in the presence of false signals that were far larger in size. Our new methodology was integrated into a scanning wafer tool, which allows for nondestructive, laterally resolved surface characterization measurements and even has the capability of measuring optical and magneto-optical properties simultaneously. (paper)

[en] We perform a detailed comparative study of conventional transverse magneto-optical Kerr effect (T-MOKE) measurements and a methodology that utilizes an effective polarization detection scheme for mixed s- and p-polarized incoming light. To test the ultimate sensitivity of both methods, we also design a series of specialized samples in which the T-MOKE signal of a Co-film is artificially reduced by means of a Ag overcoat of varying thickness. We find that the effective polarization detection scheme leads to a more than 30-fold increase of the T-MOKE signal and signal-to-noise ratio, even under general operation conditions which were not individually optimized. This allowed for the observation of T-MOKE hysteresis loops of Co-films that were buried under 80 nm of Ag, for which the MOKE signal was only 1/600 of that for an uncoated Co-film. In comparison, conventional T-MOKE measurements did not succeed for Ag overcoats thicker than 40 nm. (letter)

[en] We present results of an analysis of all available data of the double-lined spectroscopic and eclipsing binary HP Draconis. The analyses make use of unpublished radial velocity (RV) and extensive photoelectric photometry data as well as published Hipparcos photometric observations and RV data from Asiago Observatory. The system is eccentric and the current analyses suggest apsidal motion to be present only weakly, but a significant amount of third light is found in all three passbands, B, V, and hip. Relatively high precision has been achieved for the mass and radius among the absolute parameters with fractional error of 0.95% or better: M_1,2 = 1.133 ± 0.005, 1.094 ± 0.007 M_sun; R_1,2 = 1.371 ± 0.012, 1.052 ± 0.010 R_sun. Other derived parameters are P = 10.76152 ± 0.00019 days, a = 26.79 ± 0.04 R_sun, e = 0.0367 ± 0.0009, ω = 0.693 ± 0.037, q = 0.966 ± 004, and ΔT = 105 ± 5 K. We derive a distance to the system of 77 ± 3 pc. Comparison with Padova theoretical models for different chemical compositions suggests that the components may be of solar age and roughly solar composition, with the primary component less than half as dense as the secondary component and slightly evolved off the zero-age main sequence.