Search Results - "Van Wyk, H J"

Sex, size and isotopes: cryptic trophic ecology of an apex predator, the white shark Carcharodon carcharias by French, G. C. A., Rizzuto, S., Stürup, M., Inger, R., Barker, S., van Wyk, J. H., Towner, A. V., Hughes, W. O. H.

“…Demographic differences in resource use are key components of population and species ecology across the animal kingdom. White sharks ( Carcharodon carcharias )…”
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The effects of anti-androgenic and estrogenic disrupting contaminants on breeding gland (nuptial pad) morphology, plasma testosterone levels, and plasma vitellogenin levels in male Xenopus laevis (African clawed frog) by VAN WYK, J. H, POOL, E. J, LESLIE, A. J

“…Nuptial pads are areas, digits, and forearm characterized by epidermal keratin hooks and dermal breeding glands opening on the epidermis surface in male frogs…”
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A study on systematic theology by Van Wyk, J. H.

“…The author argues that although ‘Christian faith is a living relationship with Jesus Christ, our “personal Saviour”’ (II:243), the idea of a bodily…”
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A Watershed Approach in Identifying Key Abiotic Ecosystem Drivers in Support of River Management: a Unique Case Study by de Klerk, A. R., Oberholster, P. J., van Wyk, J. H., de Klerk, L. P., Botha, A.-M.

“…Since the industrial revolution, the impact of effluents produced by human activities on ecosystems has been a major international environmental concern. This…”
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Thyroid function of steatitis-affected Mozambique tilapia Oreochromis mossambicus from a sub-tropical African reservoir by Dabrowski, J, Oberholster, P, Steyl, J, Osthoff, G, Hugo, A, Power, D M, van Wyk, J H

“…Thyroid function and nutritional indicators were measured in obese, steatitis-affected Mozambique tilapia Oreochromis mossambicus from Loskop Reservoir (LR),…”
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Saccharification of Different Delignified Sawdust Masses from Various Trees Along the Lagos Lagoon in Nigeria by Ndukwe, N. A., Seeletse, J. B. M., van Wyk, J. P. H.

“…Sawdust, a major waste product of the forestry industry, is accumulating along the Lagos Lagoon in Lagos, Nigeria, without it being effectively managed…”
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A critical review of low-carbohydrate diets in people with Type 2 diabetes by van Wyk, H. J., Davis, R. E., Davies, J. S.

“…Aims The efficacy of low‐carbohydrate diets (LCD) in people with Type 2 diabetes has divided the nutrition community. This review seeks to re‐examine the…”
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Isolation and characterization of three estrogen receptor transcripts in Oreochromis mossambicus (Peters) by Esterhuyse, M.M., Helbing, C.C., van Wyk, J.H.

“…Exposure of aquatic organisms to 17β-estradiol (E 2) induces a variety of estrogen-responsive genes, including vitellogenin ( vtg)—the precursor protein of egg…”
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Saccharification of Various Wastepaper Materials by Cellulase from Brown Garden Snail (Cornu aspersum) at Different Incubation pH Values by Ndlovu, T. M., van Wyk, J. P. H.

“…Increased solid waste pollution and the negative effect of fossil fuel consumption on the environment are issues that would require more scientific attention…”
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Bacteria as biological control agents of freshwater cyanobacteria: is it feasible beyond the laboratory? by Ndlela, L. L., Oberholster, P. J., Van Wyk, J. H., Cheng, P. H.

“…Biological control of cyanobacteria is a well-researched area with a central focus on laboratory-scale studies. Numerous reports have been made on algicidal…”
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An overview of cyanobacterial bloom occurrences and research in Africa over the last decade by Ndlela, L.L., Oberholster, P.J., Van Wyk, J.H., Cheng, P.H.

“…Cyanobacterial blooms are a current cause for concern globally, with vital water sources experiencing frequent and increasingly toxic blooms in the past…”
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Comparative Early Life Stage Toxicity of the African Clawed Frog, Xenopus laevis Following Exposure to Selected Herbicide Formulations Applied to Eradicate Alien Plants in South Africa by Babalola, Oluwaseun O., Van Wyk, J. H.

“…The rise in pesticides application has increased the need for better understanding of their ecological impacts. The global amphibian declines, for example,…”
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The use of IL-6 induction as a human biomarker for inflammatory agents in water by POOL, E. J, JAGALS, C, VAN WYK, J. H, JAGALS, P

“…A rapid whole blood culture (WBC) assay system was developed to monitor the inflammatory potential of water samples collected in the Manguang Municipal area,…”
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Characterization of vtg-1 mRNA expression during ontogeny in Oreochromis mossambicus ( PETERS) by Esterhuyse, M.M., Venter, M., Veldhoen, N., Helbing, C.C., van Wyk, J.H.

“…The yolk-precursor lipoprotein, vitellogenin (VTG) has been widely recognized as a biomarker for the detection of estrogenic activity in water-borne chemical…”
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Validation of an ex Vivo Xenopus Liver Slice Bioassay for Environmental Estrogens and Estrogen Mimics by Hurter, E., Pool, E.J., Van Wyk, J.H.

“…A sensitive ex vivo bioassay for detecting environmental estrogens and estrogen mimics was developed using Xenopus liver slice culture. Vitellogenin synthesis…”
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A laboratory based exposure of Microcystis and Oscillatoria cyanobacterial isolates to heterotrophic bacteria by Ndlela, L.L., Oberholster, P.J., Van Wyk, J.H., Cheng, P.H.

“…Biological control of cyanobacteria is a viable means of controlling nuisance bloom occurrences; however the majority of studies done are against Microcystis…”
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The tooth, the whole tooth and nothing but the tooth: tooth shape and ontogenetic shift dynamics in the white shark Carcharodon carcharias by French, G. C. A., Stürup, M., Rizzuto, S., van Wyk, J. H., Edwards, D., Dolan, R. W., Wintner, S. P., Towner, A. V., Hughes, W. O. H.

“…Results from this study of the white shark Carcharodon carcharias include measurements obtained using a novel photographic method that reveal significant…”
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Evidence for sperm storage in common smoothhound shark Mustelus mustelus and paternity assessment in a single litter from South Africa by Maduna, S. N., Van Wyk, J. H., Da Silva, C., Gennari, E., Bester‐Van Der Merwe, A. E.

“…The present histological study of adult female common smoothhound shark Mustelus mustelus demonstrates that the species can store sperm in their oviducal…”
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Temporal expression of two Cytochrome P450 Aromatase isoforms during development in Oreochromis mossambicus, in association with histological development by Esterhuyse, M.M., Helbing, C.C., van Wyk, J.H.

“…Oreochromis mossambicus is targeted as a sentinel species for assay development to detect disruption of estrogen-dependent pathways in Southern Africa…”
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expression of selected genes linked to metabolic homeostasis in obese pansteatitis‐suffering Mozambique tilapia, Oreochromis mossambicus (Peters) by Truter, J C, Wyk, J H, Oberholster, P J, Botha, A‐M, Luus‐Powell, W J

“…The Oreochromis mossambicus (Peters) population inhabiting Lake Loskop, South Africa, is characterized by a high incidence of obesity and pansteatitis. We…”
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