ghanaopendata/ghanaian-research-english huggingface dataset:
Numerical simulation of surface energy and water balances over a semiarid grassland ecosystem in the West African Savanna

To understand surface energy exchange processes over the semiarid regions in West Africa, numerical simulations of surface energy and water balances were carried out using a one-dimensional multilayer atmosphere-SOil-VEGetation (SOLVEG) model for selected days of the dry and rainy seasons over a savanna grassland ecosystem in Sumbrungu in the Upper East region of Ghana. Te measured Bowen ratio was used to partition the residual energy into the observed sensible heat ﬂux (�) and latent heat ﬂux (LE) in order to investigate the impact of the surface energy closure on model performance. Te results showed that the model overall reproduced the diurnal changes in the observed energy ﬂuxes, especially the net radiation (Rn), compared to halfhourly eddy covariance ﬂux measurements, for the study periods. Te performance measure in terms of the correlation coefcient (�), centred root mean square error (RMSE), and normalized standard deviation (�) between the simulated � and LE and their corresponding uncorrected observed values ranged between R = 0.63–0.99 and 0.83–0.94, RMSE = 0.88–1.25 and 0.88–1.92, and � = 0.95–2.23 and 0.13–2.82 for the dry and rainy periods respectively, indicating a moderate to good model performance. Te partitioning of � and LE by SOLVEG was generally in agreement with the observations during the dry period but showed clear discrepancies during the rainy period, particularly afer rainfall events. Further sensitivity tests over longer simulation periods (e.g., 1 year) are required to improve model performance and to investigate seasonal exchanges of surface energy ﬂuxes over the West African Savanna ecosystems in more details.

Source: KNUST
A nurse scheduling using graph colouring

The aim of this thesis work is to provide effective method for solving Nurse Scheduling Problem (NSP) by satisfying the nurses, patients and hospital requirements. Nurse schedule problem is a major problem faced by many hospitals all over the world. That is a subclass of scheduling problems that are hard to solve. The work is difficult for the duty planner because the duty planner has to ensure that every scheduling decision made complies with a mixture of hard hospital rules and soft nurse preference rules. The thesis describes the design and implementation of a constraint-based nurse scheduling using graph colouring. A conflict graph was constructed and the vertices of the graph represented the different types of nurses. The vertices were then coloured using Greedy algorithm approach and this removed the various conflicts. The result was then used to create the nurses schedule. Results showed a feasible solution to the problem.

Source: KNUST
Numerical valuation of surrender options

Embedded in Life insurance contracts are surrender options and also path dependency. Surrender option stems from many reasons. Multi morbidity increases the rate of mortality and a variety of adverse health outcomes which may lead to surrendering. In Ghana, poverty levels coupled with social burdens can inform a multi-morbid person to surrender a life policy contract. The study seeks to incorporate the multi-morbid survival rate of a policy holder in the Black-Scholes model for option pricing. The solution to this model come along with its own complexities. Therefore the need to resort to numerical solutions for the option valuation. Further, a comparison is made of two finite difference algorithms in solving the proposed Black-Scholes equation ;the Crank-Nicolson method and the Implicit method. In line with these objectives, simulations of survival times were performed to compute the survival rate and the stability, consistency and convergence of these algorithms were investigated. It was observed that the algorithms were stable, consistent and converges to the exact solution. However the Explicit method of the finite difference approximation is found to be conditionally stable. Numerical solution to the Black -Scholes model and the proposed model indicates that the Crank-Nicolson method converges faster than the Implicit method for the Black-Scholes while the Implicit method converges faster than the Crank- Nicolson method. Finally it is observed that the Implicit method converges faster as the multi-morbid survival rate decreases below the short rate of the Black-Scholes model.

Source: KNUST
Numerical solution to fractional cattaneo heat equation in a semi-infinite medium

In this study, a detailed review of the article published by Qi... et al. (2013) on fractional Cattaneo heat equation in a semi-infnite medium has been made. In reviewing this article, two fractional Cattaneo heat equations modeling the heat flux and temperature distributions have been established and their exact solutions proofed in detail forms. Firstly, the solution of the fractional Cattaneo heat flux equation is established using Laplace transform. secondly, the exact solution of the fractional Cattaneo heat equation modeling temperature distribution is established in a series form through Fox-function using Laplace transform (and the inverse Laplace transform). In addition to the review, an implicit fnite difference scheme has been used to solve the three c lasses of generalized fractional Cattaneo heat equations (GCE's) in a semi-infnite medium. Three numerical examples were provided using both the analytical solutions and finite difference solutions to demonstrate the effects of fractional derivatives of orders on temperature distributions. Graphical representation of the solutions were presented using Matlab software. Finally, a comparison and discussion of the analytical and finite difference scheme solutions from the graphs of the various numerical examples have been made.

Source: KNUST
Nurses and Midwives Council, Accra

The Nurses and Midwives Council for Ghana is an administrative body set up by the Government to take charge of the Management of all Nurses and Midwives in the country, who constitute the majority of the health labour force. Although, the Council is empowered by law to function on its own, it is still under the Ministry of Health subvention and also among twenty one (21) other bodies working under the Ministry of Health, (the central government’s agency for health). The Ministry has several sectoral duties to perform hence it involves the role and service of the various twenty one (21) bodies in order to achieve its health goals for the nation. The Nurses and Midwives Council therefore performs like a sub-division of the Ministry of Health and by her functions, the Ministry finally achieves its aim of maximising healthy lives of all people resident in Ghana. The following are the twenty one (21) bodies: 1. Ghana Society for Prevention of tuberculosis 2. Christian Health Association of Ghana (C.H.A.G) 3. Medical and Dental Council of Ghana 4. Nurses and Midwives Council (for Ghana) 5. Pharmacy Board 6. Ghana Medical Journal 7. World Health Organisation (International) 8. Ghana Red Cross (Local N.G.O) 9. United Nations International Children’s Emergency Fund 10. West African Health Community 11. International Hospital Federation 12. Ghana Institute of Clinical Genetics 13. Ghana Leprosy Relief Association 14. League of Red Cross Societies 15. Environmental Quality Control Committees of Civil Engineering Department of U.S.T 16. St. John Ambulance Brigade 17. Occupational Health Examination Board 19 Oncho Therapeutic Research Unit 20. Ghana Diabetic Association - 21. Centre for Scientific Research into Plant Medicine

Source: KNUST
Numerical Simulation of Two Phase Oil-Water Flow Model Using the IMPES Method

The two phase ow model for simulating oil/water ow in petroleum reservoir simulation at the secondary recovery stage is reviewed. The formulation of two phase ow equations using the governing equations; conservation of mass, conservation of momentum, saturation and capillary pressure relations are considered and results in a coupled system of equations. The Implicit Pressure Explicit Saturation (IMPES) solution approach is employed as a numerical technique. Incompressible and slightly compressible reservoir conditions are investigated and compared numerically. The results indicate that slightly compressible conditions are more realistic and the relative errors between the fluids being incompressible and slightly compressible are linear in time.

Source: KNUST
Nutrient Inputs for Rehabilitation of Non-responsive Soils in the Guinea and Sudan Savannah Agroecological Zones of Ghana: Impact on Grain Yield and Soil Quality

Studies have shown that the continuous application of N, P, and K fertilizers has led to the depletion of secondary and micronutrients, which have become limiting nutrients hindering crop growth and yield. An on-farm trial was conducted to determine the effect of site-specific nutrient fertilizers and compost on soybean yield, phosphorus use efficiency, and soil properties, at Nyong Guma, Serekpere, Daffiama Saapare, and Naaga in northern Ghana. Nine (9) treatments (3 rates of mineral fertilizer × 3 rates of FertiSoil) were applied in a factorial combination arranged in randomized complete block design with three replications. On average, the soybean grain yield increased significantly with the combined application of FertiSoil and mineral fertilizer at full rates at Nyong Guma,Serekpere, and Naaga from <1,000 kg ha−1 to > 1,500 kg ha−1. The co-application of 50% recommended rate (RR) of mineral fertilizer and 5 t ha−1 FertiSoil increased soybean grain yield by over 250% at Daffiama Saapare. The application of 50% RR mineral fertilizer significantly increased phosphorus use efficiency by 5–55% compared to its combination with FertiSoil or FertiSoil alone at different rates across locations. Incorporation of 5 t ha−1 FertiSoil and 100% RR mineral fertilizer significantly increased exchangeable K, Ca, and Mg, and microbial C and P by 0.33, 2.84, 0.56 cmol(+) kg−1 and 102.7, 33.37 mg kg−1, respectively, at Serekpere. The combined application of 5 t ha−1 FertiSoil and 50% RR mineral fertilizer relatively increased soil organic C (42%) and available P (12%) at Naaga. The soil quality index revealed that the addition of 5 t ha−1 FertiSoil to 100% RR mineral fertilizer was the most sustainable nutrient management option across the study sites. Sole mineral fertilizer treatments at 50% RR were the most profitable in all the study locations ranging from value cost ratio (VCR) of 2.7–7.6. The application of limiting nutrients and organic amendments serves as an efficient nutrient management option to improve soil health, crop production and economic profitability on smallholder non-responsive soil

Source: KNUST
Nutrient release dynamics from decomposing organic materials and their mulching-effect on pearl millet yields in a low-input Sahelian cropping system

Organic material inputs for increased crop yields are insufficient in the Sahelian West Africa. There is a need for diversifying organic amendment sources for improved nutrient supply in low-input cropping system. The 2-year study aimed to (1) explore the rates of mass losses and nutrient release dynamics from Acacia tumida prunings (AT) and millet straw (MS) under field conditions, (2) assess termite’s contribution to the decomposition of AT and MS, and (3) ascertain the mulching-effect of these organic materials on pearl millet yields. The study was conducted in Niger using field experiment and litterbag methodology and the data modelled using single exponential decay equations. Under field con ditions, mulching with AT and MS increased millet grain yield by 35 and 33%, respectively compared to control. The harvest index (HI) in 2014 increased by 21% compared to that obtained in 2013 with the highest HI being recorded for the AT mulched treatment. The results from litterbag experiment indicated a greater dry mass losses from MS decom position in 2013 whereas relatively higher mass losses were recorded from AT decomposition in 2014. The differences in mass losses among the organic materials could be related to the interaction of soil moisture dynamics and termites’ population which are posi tively correlated with mass losses. The contribution of termites to the decomposition was estimated to be 36% for MS and 8% for AT. In 2013, at 126 days after litterbags placement, the amounts of N, P, and K released from MS were 16, 1, and 25 kg ha-1 of initial nutrient applied, respectively compared with the 22, 1, and 23 kg ha-1 recorded from AT treatment. During the same period in 2014, the total amounts of N, P and K released from MS were 15, 0.6, and 29 kg ha-1 , respectively compared to the 32 kg ha-1 of N, 1 kg ha-1 of P, and 29 kg ha-1 of K released from the AT treatment. The intrinsic organic material quality could explain markedly the variation in nutrient released among the organic material. These results indicate that Acacia tumida prunings have a potential to provide nutrient through mineralization for enhanced crop yield in the Sahel

Source: KNUST
Nutrition and other lifestyle factors associated with obesity and hypertension among adolescents in the Wa Municipality of Ghana

Obesity and hypertension are major risk factors for increased morbidity and mortality from noncommunicable diseases. A cross-sectional study was conducted in the Wa municipality of the Upper West Region of Ghana. The main objective of the study was to establish nutrition and other lifestyle factors associated with obesity and hypertension among 14-19 years adolescents. A multi-stage cluster proportional to size sampling method was used to select 302 adolescents from thirty schools (junior and senior high schools). Anthropometrics and blood pressure were measured with recommended instruments. Dietary intake, physical activity levels and body image preference were also assessed with the aid of questionnaire, to identify risk factors for both obesity and hypertension. Statistical package for social sciences (SPSS) version 20 and World Health Organisation (WHO) anthroplus software were used for analysis. Pearson correlations were done to find out association, while multiple and logistic regression were employed to identify risk factors for obesity and hypertension. The study revealed obesity and hypertension (both systolic and diastolic) prevalence of 1% and 4.0% respectively. Additionally, 10.1% of participants were overweight, 4.7% were underweight and 10.9% had elevated isolated diastolic blood pressure, while 7.0% had elevated isolated systolic blood pressure. Family history was positively associated (OR, 1.6, p, 0.014 95% CI) with obesity and overweight. The male gender was protective against overweight and obesity (OR, 0.2, p= 0.000 95% CI), while meal skipping was weakly associated with obesity or overweight (OR, 1.2, p=0.398). Waist circumference (WC) emerged as the only independent predictor of SBP in a multiple regression analysis. Binary logistic analysis showed that the male gender was an independent predictor of systolic blood pressure with 4.0 times higher risks (95% CI: 1.2-10.0), in comparison to their female counterparts. Ideal body image preferences chosen were generally good; 76.2% chose normal nutritional status image. Physical activity level was relatively high among the studied adolescents and not significantly different between overweight and non-overweight adolescents (p=0.334). Obesity prevalence was low, while hypertension was relatively high in the studied population. Further research is warranted to ascertain the factors responsible for the prevalence of hypertension.

Source: KNUST
Nutritional and clinical studies of non-conventional leaf protein sources on albino rats

The leaves of E. hirta (kaka wie adwe), I. involucrate (Iehowa dua), L. taxaracifolia (Wild lettuce) and X. saggittifolium (Kontomire) were analysed to determine their chemical composition and were used to feed animals to determine their nutritional attributes as well as their possible effects on the rats. The leaves were heat-treated and used to formulate the test diets at levels of 5, 8 and 10% protein levels. Equivalent diets containing of casein served as the controls. The Chemical studies on the leaves revealed that they are good amounts of protein, fibre, and mineral ion. High levels of oxalate, phytate, tannins, alkaloids and saponins which could greatly affect the nutritive quality of the leaf protein were found. The amino acid scores showed the leaf protein to be deficient in more than one amino acid mostly methionine and lysine.”Kaka wie adwe”, wild lettuce and Kontomire leaf proteins had methionine as the first limiting amino acid while lysine was the first limiting amino acid in Iehowa dua. The animals maintained on” Kaka wie adwe” and Lehowa dua leaf protein diets gave negative F.E.R and P.E.R but animals on wild lettuce and kontomire protein diets gave positive F.E.R. and P.E.R. All the leaves are potential antihypertensinogenic agents on the basis of the relatively low Na:K ratio of 0.073 (Iehowa dua), 0.056 (wild lettuce) and 0.050 (kontomire) and have hypocholesterolernic abilities especially the wild lettuce. The total lipids were lower in the serum, heart and kidney but slightly higher in the liver of all the animals fed with the leaf protein diets. The animals on the leaf proteins maintained comparable haematalogical picture as the control diets. The haemoglobin levels, RBC and WBC counts were comparable with those of the control diets. Methionine supplementation, however, improved the Red blood cell (RBC) and Haemoglobin (Hb) content of animals on “Kaka wie adwe”, lehowa dua and wild lettuce. Alkaline phosphatase (ALP) activity was high in all animals fed with the leaf protein diets except those maintained on Kontomire and unsupplemented lpomoea protein diets. The activity of Aspartate transaminase(AST) was not much influenced by any of the leaf proteins while Alanine transaininase(ALT) activity was greatly raised especially in those animal fed with “Kaka wie adwe” , unsupplemented Iehowa dua and kontomire protein diets. The histopathological studies did not reveal any adverse pathological alterations in any of the animals fed with the leaf protein diets, however, occasional incidence of fatty infiltration of the hepatocytes, congestion, granulomas and hyperemia were observed in a few instances.

Source: KNUST
Nutritional and clinical studies of non-conventional leaf protein sources on albino rats

The leaves of E. hirta (kaka wie adwe), I. involucrata(Iehowa dua), L. taxaracifolia(Wild lettuce) and X. saggittifolium(Kontomire) were analyzed to determined their chemical composition and were used to feed animals to determine their nutritional attributes as well as their possible effects on the rats. The leaves were heat-treated and used to formulate the test diets at levels of 5, 8 and 10% protein levels. Equivalent diets containing of casein served as the controls. The Chemical studies on the leaves revealed that they are good amounts of protein, fibre, and mineral ion. High levels of oxalate, phytate, tannins, alkaloids and saponins which could greatly affect the nutritive quality of the leaf protein were found. The amino acid scores showed the leaf protein to be deficient in more than one amino acid mostly methionine and lysine.”Kaka wie adwe” , wild lettuce and Kontomire leaf proteins had methionine as the first limiting amino acid while lysine was the first limiting amino acid in lehowa dua. The animals maintained on” Kaka wie adwe” and Iehowa dua leaf protein diets gave negative F.E.R and P.E.R but animals on wild lettuce and kontomire protein diets gave positive F.E.R. and P.E.R. All the leaves are potential antihypertensinogenic agents on the basis of the relatively low Na : K ratio of 0.073 (lehowa dua), 0.056 (wild lettuce) and 0.050 (kontomire) and have hypocholesterolemic abilities especially the wild lettuce. The total lipids were lower in the serum, heart and kidney but slightly higher in the liver of all the animals fed with the leaf protein diets. The animals on the leaf proteins maintained comparable haematalogical picture as the control diets. The haemoglobin levels, RBC and WBC counts were comparable with those of the control diets. Methionine supplementation, however, improved the Red blood cell( RBC) and Haemoglobin( Hb) content of animals on “Kaka wie adwe”, lehowa dua and wild lettuce. Alkaline phosphatase (ALP) activity was high in all animals fed with the leaf protein diets except those maintained on Kontomire and unsupplemented lpomoea protein diets. The activity of Aspartate transaxninase(AST) was not much influenced by any of the leaf proteins while Alanine transaminase(ALT) activity was greatly raised especially in those animal fed with “Kaka wie adwe”, unsupplemented lehowa dua and kontomire protein diets. The histopathological studies did not reveal any adverse pathological alterations in any of the animals fed with the leaf protein diets, however, occasional incidence of fatty infiltration of the hepatocytes, congestion, granulomas and hyperemia were observed in a few instances.

Source: KNUST
Nutritional and microbial profiles of commercially sold tuo-zaafi

The nutritional composition and microbial profiles of two types of commercially sold Tuo-zaafi under 3 storage conditions (Refrigeration, Water and Normal/Shelf) were evaluated. The two types of Tuo-zaafi were made from dehulled-soaked maize flour and undehulled maize flour. These flour samples were sampled from 5 suburbs in Kumasi and Accra respectively. Prepared Tuo-zaafi was also sampled from the 5 suburbs of these two areas and stored under Normal (Tuo-zaafi in a covered bowl), Water and Refrigeration conditions for 48h. The flours were analysed for nutrient composition (Ash, Crude Fibre, Crude Protein and Crude Fat). The Tuo-zaafi was analysed for nutrient and microbial profiles before storage, after 24h and 48h of storage. The nutrient content of the undehulled Tuo-zaafi was found to be significantly (p<O.O5) higher in. ash, 2.09%; crude fibre content was 1.58%; crude protein, 7.22% and crude fat, 1.87% relative to the dehulled Tuo-zaafi, which had 1.69%, 1.36%, 4.89% and 0.43% for ash, crude fibre, crude protein and crude fat respectively. Of the three storage methods investigated the most effective was refrigeration. After 48h none of the samples had microbial counts exceeding cfulg. This was followed by storage under water. After 48h only three out of the five samples had reached counts of 108 cfulg which indicated spoilage. Under normal/shelf storage almost all samples had reached counts of i08 cfulg at 24h. The improvement in the shelf life of the product under water storage is attributed to the anaerobic conditions created which were less favourable for the growth of the spoilage aerobic mesophiles. The predominant bacteria identified were Bacillus spp., Staphylococcus spp, and E. coli. The predominant moulds isolated were Neurospora spp, Aspergillus spp and Rhizopus spp. Yeasts isolated in the dehulled and undehulled samples were Saccharomyces spp. and Candida spp. Of the storage methods for Tuo-zaafi, refrigeration and/or water (in the absence of a refrigerator) would help extend the shelf life of Tuo-zaafi and reduce food losses due to spoilage.

Source: KNUST