Abstract: The invention provides an assay system for identifying a hydrogen-gas-producing organism, including a sensor film having a first layer comprising a transition metal oxide or oxysalt and a second layer comprising hydrogen-dissociative catalyst metal, the first and second layers having an inner and an outer surface wherein the inner surface of the second layer is deposited on the outer surface of the first layer, and a substrate disposed proximally to the outer surface of the second layer, the organism being isolated on the substrate.

Abstract: A process for selection of oxygen-tolerant, H.sub.2 -producing algal mutant cells comprising:(a) growing algal cells photoautotrophically under fluorescent light to mid log phase;(b) inducing algal cells grown photoautrophically under fluorescent light to mid log phase in step (a) anaerobically by (1) resuspending the cells in a buffer solution and making said suspension anaerobic with an inert gas; (2) incubating the suspension in the absence of light at ambient temperature;(c) treating the cells from step (b) with metronidazole, sodium azide, and added oxygen to controlled concentrations in the presence of white light.(d) washing off metronidazole and sodium azide to obtain final cell suspension;(e) plating said final cell suspension on a minimal medium and incubating in light at a temperature sufficient to enable colonies to appear;(f) counting the number of colonies to determine the percent of mutant survivors; and(g) testing survivors to identify oxygen-tolerant H.sub.2 -producing mutants.

Abstract: A water quality monitoring system (30) assessing the performance of a water purification apparatus (10) which compares the current percentage differential ion concentration or rejection ratio (R.sub.x), between the upstream inlet (12) and downstream outlet (14) of the purification apparatus (10), with a previous sequence of rejection ratios (R.sub.1, . . . R.sub.n) to determine the true performance of the water purification apparatus (10). Each R.sub.x value is determined at a different selected time for use in conjunction with a computation device (40) interconnected between a comparator device (38), calculating R.sub.x, and a storage mechanism (42), storing the sequence of (R.sub.1, . . . R.sub.n) values. The computation device (40) computes a performance value (PV) which is an indication of the filter membrane performance. This performance value is calculated according to a predetermined formula which incorporates the rejection ratios (R.sub.1, . . . R.sub.n) as variables.

Abstract: Meristematic tissue such as from shoot apices of herbaceous plants in a freezing solution containing a cryoprotectant are cooled to a temperature of at least -70.degree. C, stored when frozen and subsequently thawed at an average warming rate of at least about 24.degree. C/min when the tissue is at a temperature between about -70.degree. C and about -10.degree. C to obtain pathogen-free meristematic tissue having morphogenic potential. The donor plants from which the tissue is to be excised are cold treated to induce cellular reactions believed to be related to the winter cold hardening process, generally at a temperature between the plant freezing temperature and about 10.degree. C.