Salinity-induced survival strategy of Vibrio cholerae associated with copepods in Cochin backwaters

The occurrence of Vibrio cholerae in water, sediment and copepods was studied over a wide range of salinity using conventional and polymerase chain reaction (PCR) techniques in the Cochin backwaters. V. cholerae occurred either as culturable or non-culturable form in this tropical estuary. During the pre monsoon period when high salinity prevailed (35.5psu) V. cholerae was associated with copepods only in non-culturable form, but with the onset of monsoon when lower salinity prevailed, copepod-associated-V. cholerae reverted back to culturable form. The optimum salinity range for culturability was found to be 15-20psu. This points to the fact that salinity is a major factor that which influences V. cholerae's culturability and its association with copepods in Cochin backwaters.     

Atmospheric circulation over western Siberia in 1976–2004

Cyclonic and anticyclonic activity over western Siberia for 1976–2004 is considered. Trajectories of motion of baric formations of various genesis and their frequency are analyzed.     

Assessment of the natural resources of groundwater by using balance-hydrodynamic models

The specific features of formulation and implementation of balance-hydrodynamic simulation during different-scale studies of natural resources of groundwater. Are an example of detailed estimate of the resources and balance of groundwater in the Vologda River basin is given. It is noted that the use of balance-hydrodynamic models, in addition to an increase in the general reliability of estimates, allows the calculation of normal annual characteristics of groundwater resources with different occurrence (exceedance probability), which is impracticable when hydrodynamic methods in other formulations are used.     

Behavior of the broad Hα component in the Seyfert galaxy NGC 4151 in 1976–2003

Variations in the flux and profile of the broad Hα component in the Seyfert galaxy NGC 4151 are analyzed based on spectral observations acquired from 1976 to spring 2003. The procedure used to distinguish components is described. There is a strong correlation between the flux of the broad Hα component and the U flux of the galactic nucleus. There was an appreciable increase in the intensity of the broad Hα in 1990–2000, with the flux reaching a maximum in 1996. The intensity and shape of an emission feature that appeared in the red wing of the broad Hα component at the end of 2002 are estimated.