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The Langmuir isotherms of 1-aminobutane in isohexane slurries showed increase in clay acidity with increase in concentration of mineral acid used to leach the clay as well as the temperature at which the clay was thermally activated prior to experimentation involving adsorption of 1-aminobutane. The values of acidity for Central Uganda were low ranging from 0.07 mol/g to 0.32 mol/g yet those for clays from Eastern Uganda were high ranging from 0.1mol/g to 1.85mol/g. Basing on acidity, pH, elemental and mineral compositions, the clays from Central Uganda were found to be kaolinites or halloysites yet Eastern Uganda clays were resolved to contain nontronite and kaolinite. [ABSTRACT FROM AUTHOR]

The decrease in content of iron in the bleached oils was highest for all oils bleached. The content of copper showed the smallest change. The decrease in copper content for palm oils decreased from 0.2ppm to 0.1ppm when bleached with both Kajansi and Chelel clays which had be leached in 20% acid. The content of copper in cotton oils decreased from 0.5ppm to 0.15ppm using Kajansi clay leached in 20% acid yet when Chelel clay leached under similar conditions was used decrease was from 0.5 to 0.1ppm. Similarly, the content of iron in cotton oils bleached using Kajansi clay decreased from 2.5 to 0.2 yet that bleached using Chelel clay decreased to 0.1ppm. The content of iron in sunflower oils bleached using Kajansi clay leached in 20% acid decreased from 1.6 to 0.2ppm yet that bleached with Chelel clay under similar conditions decreased to 0.1ppm. The acid values showed that the acidity in sunflower oils is largely due to oleic acid as the average value for acids is in the range close to oleic acid, cotton-seed oil corresponded to linoleic acid. The levels of free fatty acid were found to lie in range from 3.8-3.2 for all clays used showing no significant rise. The peroxide values of bleached oils lay between 1.2 and 0.8 showing that freshly bleached oils were fit for human consumption. [ABSTRACT FROM AUTHOR]

The efficiency of recycled clays to bleach oils measured by decrease in absorbance of bleached oils was largest when recycled clays had been calcined at 450°C and leached in boiling mixture of 20% acid strength for 16 hours. The Langmuir constant a varied from 0.4x10-2 to 16 x10-2 and b increased from 4.7x10-2 to 95.38x10-2. The Freundlich constant n increased from 8x10-3 to 33x10-3 and k from 3.9x10-2 to 11.8 x10-2 as concentration of acid increased. The enthalpy of adsorption increased from -6.7x10-2 to 22.2x10-2 kJmol-1. [ABSTRACT FROM AUTHOR]

The efficiency of recycled clays to bleach oils measured by decrease in absorbance of bleached oils was largest when recycled clays had been calcined at 450oC and leached in boiling mixture of 20% acid strength for 16 hours. The Langmuir constant a varied from 0.4x10-2 to 16 x10-2 and b increased from 4.7x10-2 to 95.38x10-2. The Freundlich constant n increased from 8x10-3 to 33x10-3 and k from 3.9x10-2 to 11.8 x10-2 as concentration of acid increased. The enthalpy of adsorption increased from -6.7x10-2 to 22.2x10-2 kJmol-1. [ABSTRACT FROM AUTHOR]

Ethnographers are often sceptical of employing Participatory Rapid Appraisal (PRA) tools in their research, calling them 'a quick and dirty' approach. However, ethnography has limitations as a research method. We therefore combined the two methods to enhance their strengths. Based on fieldwork in rural Gambia, this article discusses the procedure, merits and shortcomings of triangulating PRA and conventional ethnography methods to conduct research among an illiterate study population of traditional birth attendants. When tailored to suit the target study population, some PRA tools do enhance the emic perspective--thus empowering the study participants and making research results more context-relevant. [ABSTRACT FROM AUTHOR]

The shea tree (Vitellaria paradoxa,C.F.Gaertn) is an indigenous fruit tree distributed in the shea parklands of Africa. The shea fruit is an important source of food for rural communities especially at time of food shortages, hunger and other disasters in addition to providing enormous health benefit and income. Because of its role in combating food insecurity and sustaining rural livelihoods, an assessment of the nutritional composition of shea fruit pulp was carried out in Uganda. Samples of shea fruits were collected from Katakwi, Lira, Pader and Arua districts in Teso, Lango, Acholi and West Nile sub regions in Uganda, respectively, between April and August 2007. For each district, a composite shea fruit sample was analysed for moisture content, total ash, crude oil, crude fibre, crude protein, vitamin C, carbohydrates and calorific values. The mineral composition was analysed for calcium, sodium, potassium, magnesium and iron. The total ash, crude oil, crude fibre, crude protein, total carbohydrate, vitamin C and caloric values ranged between 3.6-5.9%, 1.5-3.5%, 10-15%, 3.1-4.2%, 12.4-19.4%, 85.6-124.9mg/100g and 77.6-89.2 Kcal/100g, respectively (dry weight basis). Ca, K, Mg, Na and Fe values in the pulp ranged from 35.2-95.6 mg/100g, 42.0-63.6 mg/100g, 18.1-24.2mg/100g, 7.1-18.1mg/100gm and 3.4-3.8 mg/100g, respectively. There was a significant variation (P≤0.05) in the crude proteins, crude fibre, Vitamin C values and mineral compositions of the shea fruit pulp from the different shea sub-regions in Uganda. These variations could be due to differences in prevailing environmental factors. The results show clearly that shea fruit pulp has adequate nutrients equivalent to other edible fruits and should be promoted in human nutrition. Its Na/K ratio (0.14-0.35) also makes the shea fruit a valuable resource for managing high blood pressure; an emerging non-communicable disease in most developing countries. To promote wide consumption of shea fruits, the influence of environmental factors and season of harvest on its nutritional composition needs to be investigated. [ABSTRACT FROM AUTHOR]

Shea oil is a vegetable oil obtained from the seeds of the shea tree (Vitellaria paradoxa C.F. Gaertn.). It constitutes an important source of fat in food and cosmetics. Although shea oil can be marketed both locally and internationally, increasing demand worldwide for exportable products calls for their certification. Characterization of shea oil is one step towards developing its certification system. In this study, the physico-chemical characteristics of shea oil in different shea zones of Uganda were assessed. Samples of shea fruits were collected between the months of June-August 2007 in the districts of Pader, Lira, Katakwi and Arua representing Acholi, Lango, Teso, and West Nile shea zones, respectively. Seed oil was extracted by Soxhlet apparatus using n-hexane solvent and analysed for colour, refractive index, viscosity, oil content, acid value, peroxide value, saponification value, iodine value, α-tocopherols and fatty acid profile. Shea oil content, colour, refractive index and viscosity ranged from 41-54%, orange to orange-yellow, 1.670-1.690 and 2.4-2.8 cP, respectively. Acid and peroxide values ranged between 2.3-12.59 mgKOH/kg and 2.10 to 2.50 meq/kg, respectively. Saponification, iodine and α- tocopherols values were between 160 mgKOH/g and 192mgKOH/g, 39.21 I2g/100 and 41.37 I2g/100g and 26.3-44.4 mg/100g, respectively. Fatty acid profile for palmitic, stearic, oleic, linoleic and arachidic fatty acids ranged between 6.52-8.12%, 28.65-30.94%, 55.54-57.63%, 6.18-7.79% and 0.65-0.90%, respectively. Although there was significant variation in the oil yield (P≤0.05), the physico-chemical characteristic and fatty acid profile showed no significant variation in the shea zones of Uganda (P≤0.05). The fact that physico-chemical characteristics of shea oil from the different shea zones of Uganda are comparable to other high value edible vegetable oils indicates its suitability as raw material for food, cosmetic and pharmaceutical products. This characterization is a bench mark for monitoring the quality of shea oil from Uganda and can be used to enhance its local and international trade. [ABSTRACT FROM AUTHOR]