Constructed wetlands: A future alternative wastewater treatment technology

Wastewater treatment will always pose problems if there are no new alternative technologies in place to replace the currently available technologies. More recently, it has been estimated that developing countries will run out of water by 2050. This is a course for concern not only to the communities but also a challenge to the scientist to find new ways of wastewater recycling. Water losses can be avoided through implementation of easy and inexpensive technologies for wastewater treatment. Environmental concerns over insufficiently performing septic systems and high expenses in the construction of sewer systems as well as their operations with centralized water purification systems have spurred investigation into the appropriateness of the use of wetland technology for wastewater treatment. Constructed wetland efficiency and potential application in wastewater treatment has been reported decades ago. However, the logistics and research for their commercial applications in wastewater treatment has not been documented in details. Research has shown that wetland systems can achieve high treatment efficiencies with regards to both organic and inorganic nutrients as well as pathogen removal if properly managed and efficiently utilized. This can have a profound effect in the management and conservation of our scarce and yet depleting water resources.Keywords: Constructed wetlands, rhizofiltration, microbial biofilms, wastewater treatment, treatment mechanismAfrican Journal of Biotechnology Vol. 12(29), pp. 4542-455

p17 from HIV induces brain endothelial cell angiogenesis through EGFR-1-mediated cell signalling activation

© 2018, United States & Canadian Academy of Pathology. HIV-associated neurocognitive disorder in HIV patients substantially reduces their quality of life. We previously showed that the HIV matrix protein, p17 could stimulate lymph-angiogenesis in vitro potentially contributing to lymphoma tumour growth and in addition is associated with vascular activation in neuro-degenerating brain tissue; here, therefore, we have investigated the detailed molecular mechanisms of this action. We performed in vitro cell culture, angiogenesis experiments, phospho-protein microarrays and Western blotting to identify cellular signalling induced by p17 within human brain endothelial cells (HbMEC), and inhibitor studies to block p17-induced vascular growth. We also characterised the effects of hippocampal CA1 injection of p17 on epidermal growth factor receptor-1 (EGFR1) expression linked to our murine model of dementia. p17 strongly induced angiogenesis of HbMEC (migration, tube formation and spheroid growth). p17 concomitantly increased phosphorylation of EGFR1 as well as down-stream intermediates ERK1/2, FAK, PLC-γ and PKC-β whilst an inhibitor peptide of EGFR, blocked cell signalling and angiogenesis. Finally, Mice that showed reduced cognitive function and behavioural deficiencies after p17 injection, demonstrated that p17 localised in cortical microvessels and also neurones many of which stained positive for p-EGFR1 by histology/IHC. This work provides strong support that p17 may be involved in initiating and/or perpetuating vascular tissue pathophysiology associated with comorbidity in HIV patients

Mechanics 1

Exam paper (Supplementary) for first semester National Diploma, Mechanical Engineerin