Bio-recovery of N and P from an anaerobic digester effluent: The potential of duckweed (Lemna minor)

The possibility of growing duckweed (Lemna minor) on anaerobic digester effluent and its nitrogen and phosphorus acquisition potential was studied. Duckweed was cultured for 21 days on an anaerobic digester effluent using two methods: static aeration (SAT) and normal batch reactor (NBR) techniques, respectively. The treatments involved pure effluent and 1/10, 1/25 and 1/50 effluent dilutions, respectively. Fifty duckweed fronds were grown in the anaerobic digester effluent for 21 days. At the end of the growth period, phosphate levels, total ammonium nitrogen (TAN) andtotal oxidized nitrogen (TON) contents of the growth media were determined. Total nitrogen concentration and orthophosphate P content in the duckweed were also determined. The results obtained indicated that duckweed was capable of growing on the anaerobic digester effluent provided its TAN content did not exceed 42 mg N l-1. Nitrogenuptake by the duckweed from the effluent ranged between 53 and 115.7 mg l-1 whereas P uptake varied from 1.40 to 8.4 mg P l-1. The relative growth rate of duckweed in the anaerobic digester effluent was observed to be comparable to literature value of 0.22 mg day -1. The results have demonstrated that duckweed has the potential to recover N and P from anaerobic digester effluent

Effect of management of mucuna (Mucuna pruriens var. utilis) live-mulch on some properties of a haplic acrisol

No Abstract. Agricultural and Food Science Journal of Ghana Vol. 4 2006: 291-29

N2O Emissions and Inorganic N Release Following Incorporation of Crop Residue and/ or Inorganic N Fertiliser into Soil

Nitrous oxide emissions are usually increased following incorporation of crop residues or inorganic N fertiliser into soil, but the effect of combining these inputs at different proportions on N dynamics and NO emissions has 2 yet to be adequately examined. The interactive effect of combining crop residues barley (Hordereum vulgare) and clover (Trifolium pretense) and inorganic N fertiliser (NH4NO3) on N2O emission and mineral N dynamics under controlled laboratory conditions is reported. Emissions of NO were significantly higher from soils amended with 2 the low C:N ratio clover residues compared to the high C:N ratio barley residue treatments and was further increased, following combined application of crop residues and inorganic N fertiliser. Furthermore, the magnitude of emission was influenced by the proportions at which the residue-N and the fertiliser-N were combined with the 75:25 fertiliser:clover treatment emitting the highest (P < 0.05) amount of 65 mgN2O-N m-2 30 d-1. Incorporation of sole clover residues resulted in net N mineralization and addition of sole barley residues led to a net N immobilization. However, combined application of either residue with inorganic N fertiliser resulted in netNmineralisation. The results from the study demonstrated that whilst there is the potential for N2O emission to be controlled through varying ratios of residue:fertiliser input, the magnitude and direction of interactions between these N sources vary between different species as a result of their different qualities. This relationship should be verified under field conditions

Prostate cancer screening in Ghana - a clinical benefit?

In Ghana and most African countries, prostate cancer is the most common cancer in males after hepatocellular carcinoma. Whereas in the advanced countries, screening for prostate specific antigen (PSA) has led to early detection and management of the disease, screening has been very low in Ghana, thus leading to low detection rate, poor management and increased mortality. The aim of our study therefore was to provide the basis for the advocacy and promotion of prostate cancer screening in Ghana so as to improve early detection, management and prognosis. To do this, we estimated serum PSA levels of 196 men randomly reporting to the Out-Patient Department (OPD) of the Komfo Anokye Teaching Hospital for screening. We employed the enzyme immunoassay (EIA) method as our non-invasive screening procedure. We also conducted a survey on the prevalence of the disease as reported at five major hospitals in the country. It was observed that 83.6% of the subjects who had their PSA levels above the upper limit of the reference range (4 ng/ml), with their ages ranging between 56 to 85 years. Coincidentally, our survey also revealed that 96.5% of those who had the disease within the period of study were above 50 years. The significance and relevance of these findings to PSA screening in the country and its accuracy in diagnosing prostate cancer cannot be overemphasized. Journal of Science and Technology Vol. 25(2) 2005: 9-1

Prostate cancer screening in Ghana - a clinical benefit?

In Ghana and most African countries, prostate cancer is the most common cancer in males after hepatocellular carcinoma. Whereas in the advanced countries, screening for prostate specific antigen (PSA) has led to early detection and management of the disease, screening has been very low in Ghana, thus leading to low detection rate, poor management and increased mortality. The aim of our study therefore was to provide the basis for the advocacy and promotion of prostate cancer screening in Ghana so as to improve early detection, management and prognosis. To do this, we estimated serum PSA levels of 196 men randomly reporting to the Out-Patient Department (OPD) of the Komfo Anokye Teaching Hospital for screening. We employed the enzyme immunoassay (EIA) method as our non-invasive screening procedure. We also conducted a survey on the prevalence of the disease as reported at five major hospitals in the country. It was observed that 83.6% of the subjects had their PSA levels above the upper limit of the reference range (4 ng/ml), with their ages ranging between 56 to 85 years. Coincidentally, our survey also revealed that 96.5% of those who had the disease within the period of study were above 50 years. The significance and relevance of these findings to PSA screening in the country and its accuracy in diagnosing prostate cancer cannot be overemphasized. Keywords: prostate cancer, screening, diagnosis, prostate specific antigen (PSA) Journal of Science and Technology Vol. 26(1) 2006: 1-