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Abstract: The aim of the work was to develop a new capacitive sensor based on the electrostriction phenomenon observed in membranes deposited on solid electrodes in contact with an electrolyte solution. The functioning of the sensor was checked in determination of ionic surfactants. The sensor was based on self-assembled monolayers (SAM''s) of thiol supported on the surface of a gold electrode. Two thiols, 1-octadecanethiol and 1-hexadecanethiol, and two surfactants, anionic sodium dodecyl sulfate and cationic hexadecyltrimethylammonium bromide, were chosen for studies. Different shapes of capacitance-potential curves with hysteresis were revealed. After an addition of a surfactant, the height of hystheresis changed, enabling construction of linear relationship between the hystheresis’ height and concentration of surfactant. [Copyright &y& Elsevier]

Anadromous Atlantic salmon from 12 rivers in Maine, 3 rivers in New Brunswick, and 2 rivers each in Nova Scotia, Quebec, Newfoundland, and Labrador as well as 2 landlocked strains in Maine ( N = 3,863) were genotyped at 11 microsatellite loci. Fish in the drainages of Maine's Kennebec and Penobscot rivers were genetically similar to those sampled from the 8 rivers recently listed as containing an endangered distinct population segment under the United States' Endangered Species Act. Genetic distance estimates confirm that Maine's Atlantic salmon, both landlocked and anadromous, represent a discrete population unit, genetically as independent from any Canadian population as the Canadian populations are from each other. Within Maine, the anadromous and landlocked populations were statistically distinct. Anadromous Atlantic salmon were more genetically similar among year-classes within rivers than among rivers, as would be expected if the river is the unit of population. The effective number of breeders estimated within each river is larger than the number of adults estimated from samples and redd counts over the 10-year period from 1991 to 2000. [ABSTRACT FROM AUTHOR]