We used a combination of genomic techniques to monitor chromosomal evolution across hundreds of generations as Escherichia coli adapted to growth-limiting concentrations of either lactulose, methyl-galactoside, or a 72:28 mixture of the two. DNA microarrays identified 8 unique duplications and 16 unique deletions among 42 evolvants from 23 chemostat experiments. Each mutation was confirmed by s...

Perpendicular orientation of the electron donor in relation to the acceptor in the ground state seems to contribute significantly to high rate constants of the photoinduced intramolecular electron transfer (PET) in electron donor-acceptor (DA) type molecules [1]. A very interesting class of molecules in this respect are systems build around a spiro-type carbon atom, separating mutually orthogon...

Doris E. Vidal ABSTRACT Resistance to contaminants is an important yet unmeasured factor in sediment toxicity tests. The rate at which mercury resistance develops and its genetic persistence in the oligochaete worm Tubifex tubifex were studied under laboratory conditions. Two populations of T. tubifex worms were raised for four generations each in clean and mercurycontaminated sediments, respec...

The objective of this study was to determine how alternative on-site wastewater treatment systems (i.e. subsurface flow constructed wetlands, intermittent sand filters and intermittent peat filters) affect the viability and culturability of Salmonella choleraesuis (serotype typhimurium, ATCC 23567). Influent was a high strength septic tank effluent (BOD5 240-344 mgL(-1), TN approximately 100 mg...

This study shows that a short-term respirometric measurement based on the rate of oxygen uptake needed to oxidize glucose is a reliable and fast method to assess biocide efficacy against P. fluorescens cells. Respiratory activity using oxygen consumption rate, the determination of viable and nonviable cells using Live/Dead BacLight kit and colony formation units (CFU), were compared as indicato...

This study aimed to investigate the toxicological effects of the LAS-C12 on Mugil platanus (mullet). Fishes exposed to 1.0 mg.L for 24, 48, 72, 96 and 120 hours presented significant increase in specific routine metabolism. At the concentration of 0.5 mgL, the active metabolism presented a decreasing trend from 48 h of exposure on. However, only the consumption averages for 72 h were statistica...

The Pseudomonas aeruginosa GSM3 isolated from dye contaminated soil was able to degrade Reactive Violet 5 completely as a sole source of carbon (300 mgL) within 20 h under static condition. The organism exhibited good decolorization ability in the pH ranges from 5.0 to 9.0 and temperature from 30 to 40C respectively. The optimum degradation was observed at 37C and pH 7. The maximum concentratio...

in this study, rainbow trout (oncorhynchus mykiss) eggs were treated with effective doses of  daenensis thyme, thymus daenensis (20, 10 and 5 mgl-1) and mentha, mentha longifolia (10, 5 and 2.5 mgl-1), during incubation period (20 days) until hatching for 30 minutes per every other day as constant flow bath treatment method. the mortality level in normal control (without any treatment) was sign...