An active filter feeding organism strains suspended matter from the surrounding water using a sieving structure. Small marine filter feeders however, have to cope with the physical problems of the high viscosity as indicated by the low Reynolds number. In a highly viscous regime, organisms' appendages are surrounded by a thick boundary layer, which makes movement and filter feeding difficult. I...

Maritime pine bark (Pinus pinaster Aiton subsp. atlantica) is rich in polyphenols with known bioactive properties which are beneficial for human health. However, biological activities of extracts depend on the type extracted and characteristics these extractives several factors such as solvents used. The influence extraction solvent composition consequently has been poorly described. Thus, this...

In order to optimize callus induction in Pistacia atlantica Desf. subsp. kurdica Rech. f., the effect of different plant growth regulator (PGR) combinations were studied. Inflorescence axis explants were cultured on WPM medium supplemented with 1, 2 and 3 mg/L of TDZ or 1, 2 and 3 mg/L of BA, in combination with 1mg/l different auxins: 2, 4-D,  NAA  and IBA . Callus initiation was observed in a...

The endemic South African sac spider genus Lessertina Lawrence, 1942, previously known only from the type species (L. mutica Lawrence, 1942), is revised. Both sexes of L. mutica are redescribed and the species is recorded from the Eastern Cape, KwaZulu-Natal and Limpopo Provinces. A new species, L. capensis sp. nov., is described from the Eastern and Western Cape Provinces.

Sexual development has long been the target of study and despite great advances in our understanding of the composition and regulation of the gene network underlying gonadogenesis, our knowledge remains incomplete. Of particular interest is the relative role that the environment and the genome play in directing gonadal formation, especially the effect of environmental temperature in directing t...