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The subject was presented with a pair of lines. One line was an objective referent line Ro and did not change its length. The other was a test line and changed the its length. The observer must report--where the longer line was--above or below in the pair. On the basis neurophysiological, psychophysical data and new type of the psychometrical curve a complex neuronal construction was built. The comparison of action of the neuronal construction with the psychophysical data on different stages of introduction the visual information showed that in both cases at first stages of introduction the information referent subjective stimulus Rs is not equal to Ro. But at the last stages, when Weber's fraction is obtained Rs = Ro. This result allows to suggest that the suggested neuronal contraction is near to the real constriction of the visual brain.

The subjects learned to recognize three figures presented in the left visual hemifield and three figures presented in the right visual hemifield. During presentation of a stimulus, the contralateral hemifield was overlapped by a mask. After the training, recognition of all six figures presented in the right and left visual hemifields, was compared. Each hemisphere recognizes figures which were learned in the corresponding visual hemifield, but the recognition of figures learned in the opposite visual hemifield was poor. Thus, the ability of the hemispheres to act separately in recognizing different sets of visual images, was established.

Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comprehensive investigation of DBPs formed by chlorine dioxide under high bromide conditions. Drinking water from full-scale treatment plants in Israel was studied, along with source water (Sea of Galilee) treated under carefully controlled laboratory conditions. Select DBPs (trihalomethanes, haloacetic acids, aldehydes, chlorite, chlorate, and bromate) were quantified. Many of the DBPs identified have not been previously reported, and several of the identifications were confirmed through the analysis of authentic standards. Elevated bromide levels in the source water caused a significant shift in speciation to bromine-containing DBPs; bromoform and dibromoacetic acid were the dominant DBPs observed, with very few chlorine-containing compounds found. Iodo-trihalomethanes were also identified, as well as a number of new brominated carboxylic acids and 2,3,5-tribromopyrrole, which represents the first time a halogenated pyrrole has been reported as a DBP. Most of the bromine-containing DBPs were formed during pre-chlorination at the initial reservoir, and were not formed by chlorine dioxide itself. An exception wasthe iodo-THMs, which appeared to be formed by a combination of chlorine dioxide with chloramines or chlorine (either added deliberately or as an impurity in the chlorine dioxide). A separate laboratory study was also conducted to quantitatively determine the contribution of fulvic acids and humic acids (from isolated natural organic matter in the Sea of Galilee) as precursor material to several of the DBPs identified. Results showed that fulvic acid plays a greater role in the formation of THMs, haloacetic acids, and aldehydes, but 2,3,5-tribromopyrrole was produced primarily from humic acid. Because this was the first time a halopyrrole has been identified as a DBP, 2,3,5-tribromopyrrole was tested for mammalian cell cytotoxicity and genotoxicity. In comparison to other DBPs, 2,3,5-tribromopyrrole was 8x, 4.5x, and 16x more cytotoxic than dibromoacetic acid, 3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone [MX], and potassium bromate, respectively. 2,3,5-Tribromopyrrole also induced acute genomic damage, with a genotoxic potency (299 microM) similar to that of MX.

A scale-invariant algorithm of image description that is derived from the investigations of the neural structure of striate complex modules is proposed. First an image is preprocessed by difference-of-Gaussians functions, then the Gabor expansion in modules of different scales is used, and a group of the most excited modules is looked for with the help of scale weighting functions (SWF's). Finally, the image code is calculated as a linear combination of the output signals from the Gabor modules. The coefficients of this linear combination correspond to the SWF selected in the previous step. The scales of Gabor modules are chosen to be a logarithmic sequence with a half-octave step. Because of the SWF method, the described algorithm takes into account all the image sizes on a continuum between the minimum and the maximum scales of the Gabor modules.