Studies on the Ecology, Growth and Physiology of Toxic Microcystis Aeruginosa in South Africa

Abstract Cyanobacteria are known for their extensive and highly visible blooms in rivers or dams in Africa. One of the most important cyanobacteria is Microcystis aeruginosa which can synthesise various microcystins that may affect the health of humans and animals. Accurate and efficient detection of microcystins in water is thus important for public and veterinary health. Two enzyme-linked immunosorbent assays (ELISA), a commercially-available ELISA kit (Abraxis) and a newly-developed Norwegian ELISA (putatively cheaper and more robust) were used to detect microcystins in fresh water in South Africa. Water samples were collected monthly at two sites, the Hartbeespoort Dam and a crocodile breeding dam. Extremely high microcystin concentrations (exceeding 360 μg L−1) were detected in the Hartbeespoort Dam during January 2015, whereas the microcystin concentrations in the crocodile breeding dam peaked during March–April 2015. Both ELISAs were positively correlated when analysing water samples ‘as is’ and following resin adsorption and methanol extraction. However, following resin adsorption and methanol extraction of the water samples, the correlation between the two assays was much stronger. These results suggests that the two ELISAs provide comparable results. If the Norwegian-developed ELISA can be packaged and made available as a user-friendly kit, it could be used successfully in surveillance programmes to monitor microcystin concentrations in fresh water bodies in Africa.

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Microcystis Aeruginosa and Underwater Light Attenuation in a Hypertrophic Lake (Hartbeespoort Dam, South Africa)

Journal of Ecology ◽

10.2307/2259547 ◽

1984 ◽

Vol 72 (3) ◽

pp. 1001 ◽

Cited By ~ 72

Author(s):

R. D. Robarts ◽

T. Zohary

Keyword(s):

South Africa ◽

Microcystis Aeruginosa ◽

Light Attenuation ◽

Hypertrophic Lake ◽

Underwater Light

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Time and Latitude in South Africa

International Astronomical Union Colloquium ◽

10.1017/s0252921100026816 ◽

1972 ◽

Vol 1 ◽

pp. 27-38

Author(s):

J. Hers

Keyword(s):

South Africa ◽

Cape Town ◽

Astronomical Observations ◽

Royal Observatory ◽

The Republic ◽

Astronomical Determination ◽

Limited Accuracy ◽

Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

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Indirect Rule in South Africa

10.1017/upo9781580467421 ◽

2009 ◽

Author(s):

J. C. Myers

Keyword(s):

South Africa ◽

Indirect Rule

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Combining Professional Interests and Travel: People to People Citizen Ambassador Program

Perspectives on Global Issues in Communication Sciences and Related Disorders ◽

10.1044/gics1.2.47 ◽

2011 ◽

Vol 1 (2) ◽

pp. 47-54

Author(s):

Alex Johnson ◽

Amanda Hitchins

Keyword(s):

South Africa ◽

Health Education ◽

Communication Disorders ◽

Social Conditions ◽

Speech Language Pathologists ◽

Exchange Program

Abstract This article summarizes a series of trips sponsored by People to People, a professional exchange program. The trips described in this report were led by the first author of this article and include trips to South Africa, Russia, Vietnam and Cambodia, and Israel. Each of these trips included delegations of 25 to 50 speech-language pathologists and audiologists who participated in professional visits to learn of the health, education, and social conditions in each country. Additionally, opportunities to meet with communication disorders professionals, students, and persons with speech, language, or hearing disabilities were included. People to People, partnered with the American Speech-Language-Hearing Association (ASHA), provides a meaningful and interesting way to learn and travel with colleagues.

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