Salinity is rising in many southern African and Australian rivers with unknown effects on aquatic organisms. The extent of spatial variation, at any scale, in salt tolerances is unknown and therefore whether data from one location should be used elsewhere. The acute tolerances (72-hour LC50) to sea salt of 49 macroinvertebrate taxa from the south-east of the Eastern Cape (SEEC), South Africa we...

By passage through a series of eleven rabbits a culture of the hogcholera bacillus has increased its virulence a thousand times. A subcutaneous injection of twenty organisms, or 0.00000001 cc. of a 24 hour bouillon culture, or a drop of a bouillon culture rubbed lightly into the shaven skin, produces, in the rabbit, a characteristic disease resulting in death on or about the 6th day.

The efficacy of decontamination using Sterilox fog was assessed against meticillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii. Ceramic tiles were inoculated with the test organisms and, once dried, were subjected to Sterilox fogging using a stationary vaporizing machine sited at a distance of 3m for 10 min and then left for a further hour. In a second experiment using th...

Flow cytometry is a rapid method to quantitate live and dead bacteria in a sample.1-4 It can be used to measure the efficacy of antimicrobial compounds by exposing organisms to the disinfectant and subsequently staining with permeant and impermeant DNA dyes. Test organism viability, measured using a 30-minute flow cytometry assay, showed comparable sensitivity with a standard 48-hour plate coun...

For rapid results, we adapted the CarbaNP test by using 5-hour-old cultures; the sensitivity and specificity for detection of carbapenemase production were 100% for non-OXA-producing organisms. The sensitivity from early cultures was 94% for detection of carbapenemase production in Enterobacteriaceae strains. Utilizing younger cultures allows the test to be incorporated into a single day's work...

the production and use of synthetic nanoparticles is growing rapidly, and therefore the presence of these materials in the environment seems inevitable. titanium dioxide (tio2) presents various possible uses in industry, cosmetics, and even in the treatment of contaminated environments. studies about the potential ecotoxicological risks of tio2 nanoparticles (nano-tio2) have been published but...

recently, some natural products have been used in the fields as alternative to synthetic compounds, to minimize the negative impacts to the environment. this study aimed to verify the effects of neem-based bio-pesticide in causing acute toxicity for a fish and chronic toxicity for a microcrustacean. to this end, danio rerio and daphnia magna were exposed to various concentrations of a neem-base...

the production and use of synthetic nanoparticles is growing rapidly, and therefore the presence of these materials in the environment seems inevitable. titanium dioxide (tio2) presents various possible uses in industry, cosmetics, and even in the treatment of contaminated environments. studies about the potential ecotoxicological risks of tio2 nanoparticles (nano-tio2) have been published but ...