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This paper presents results of an experimental study of chemical coagulation for the pre-treatment of constructed wetlands. The wastewater was generated from a municipal wastewater treatment plant. We investigated the important parameters that affect removal efficiency of phosphate and turbidity, such as pH, coagulant type and dosage, and addition of coagulant aid. The coagulation jar test showed that polyaluminium chloride (PACl) was more efficient than polymerized aluminium ferric chloride (PAFCl) for phosphate and turbidity removal. Residual turbidity and phosphate removal efficiencies increased with pH value. The selection of appropriate PACl dosage depended on the target wastewater property to be removed. The addition of the coagulant aid polyacrylamide (PAM) reduced residual turbidity and improved phosphate removal efficiency when used with PACl. The pilot experiment showed that when PACl and PAM were at optimal dosages of 14.8 mg Al L-1 and 3.0 mg L-1, respectively, the average effluent residual turbidity was 9.43 NTU, phosphorus concentration was 1.40 mg L-1 and chemical oxygen demand concentration was 118.57 mg L-1; all of which met constructed wetland influent standards. Chemical coagulation can, therefore, be used as an efficient pre-treatment method to reduce the contaminant load of constructed wetlands. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the neuron-like cellular differentiation of mesenchymal stem cells that are derived from human umbilical cord blood cells induced by Brain-derived neurotrophic factor. It mentions that adherent cells exhibited neuron-like cellular morphology following the treatment with neural induction medium. Results indicate that the said mesenchymal stem cells can differentiate into neuron-like cells induced by brain-derived neurotrophic factor in vitro.