Effects of biochar and gypsum soil amendments on groundnut (Arachis hypogaea L.) dry matter yield and selected soil properties under water stress

The effects of amending soil with gypsum and biochar on groundnut chlorophyll concentration, water use efficiency (WUE), biomass yield and selected soil properties were investigated under water stress. Gypsum (CaSO4.2H2O) was applied at 0 and 200 kg/ha, groundnut shell biochar at 1, 2 and 4% w/w of soil, and water at 100, 70 and 40% of daily plant water requirement (PWR) as main, sub and sub-sub plots, respectively, in a split-split-plot design. Biochar neutralized the acid soil, significantly raising soil pH from 5 to 7.15 and increasing cation exchange capacity by 75%. Biochar amended at 1 and 2%, increased groundnut dry matter yield by 28%. The optimum biochar application rate for dry matter yield was 1.4% w/w. Biochar application at 4% and irrigation at 40% of PWR reduced the WUE by 45 and 50%, respectively. Chlorophyll concentration index was highest at 40% of PWR. The results suggest that biochar has potential to raise soil pH, increase moisture retention and improve crop performance. Applying water at 100% PWR can increase groundnut dry matter yields, while higher gypsum application rates may be required to affect crop performance

Human immunodeficiency virus infection and cerebral malaria in children in Uganda: a case-control study

<p>Abstract</p> <p>Background</p> <p>Human immunodeficiency virus (HIV)-1 infection increases the burden of malaria by increasing susceptibility to infection and decreasing the response to malarial treatment. HIV-1 has also been found to suppress the immune system and predispose to severe forms of malaria in adults. There is still a paucity of data on the association between HIV-1 infection and cerebral malaria in children. The aim of this study was to determine whether HIV-1 infection is a risk factor for cerebral malaria in children.</p> <p>Method</p> <p>We conducted an unmatched case-control study, in which 100 children with cerebral malaria were compared with 132 with uncomplicated malaria and 120 with no malaria. In stratified analyses we estimated odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for age.</p> <p>Results</p> <p>HIV-1 infection was present in 9% of children with cerebral malaria compared to 2.3% in uncomplicated malaria (age-adjusted odds ratio (aOR) 5.94 (95% confidence interval (CI) 1.36-25.94, p = 0.012); and 2.5% in children with no malaria (aOR 3.85 (95% CI0.99-14.93, p = 0.037). The age-adjusted odds of being HIV-positive among children with cerebral malaria compared to the control groups (children with uncomplicated malaria and no malaria) was 4.98 (95% CI 1.54-16.07), p-value = 0.003.</p> <p>Conclusions</p> <p>HIV-1 infection is associated with clinical presentation of cerebral malaria in children. Clinicians should ensure that children diagnosed with HIV infection are initiated on cotrimoxazole prophylaxis as soon as the diagnosis is made and caretakers counselled on the importance of adherence to the cotrimoxazole towards reducing the risk of acquiring <it>P.falciparum </it>malaria and associated complications such as cerebral malaria. Other malaria preventive measures such as use of insecticide-treated mosquito nets should also be emphasized during counselling sessions.</p