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Modelling the growth, feed intake and backfat deposition of different South African sheep breed types by Van der Merwe, Daniel Andre
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Phase equilibria studies and beneficiation of titaniferous slags by Goso, Xolisa Camagu
Published 2020“…The economic modelling of the conceptual flowsheet for a 20 year operational projection showed that the process is economically viable. …”
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- Climate change 2 results 2
- Reliability indices are considered to be reasonable and logic ways to judge the performance of an electric power system. Reliability indices which are proposed by the IEEE are used to evaluate the performance of selected distribution systems on the national grid. Ten years of outage data (1998 - 2007) from seven selected distribution systems on the national grid were used as case studies in this research work. A generalized model is developed for a quantitative evaluation of relative indices of the national grid system. The development of the model stated with identification of the system reliability indices and estimating the contributions of system indices to the failure rate of the selected distribution system on the national grid. The computed system reliability indices are used as input parameters for the generalized model. Relative CAIDI index is computed by simulation using MATLAB 7.7 which automatically generates the graph of the relative CAIDl against names of feeders. The percentage average relative CAIDls for Ibadan, Port-Harcourt and Benin distribution systems are 71.86%, 52.79% and 75.79% respectively, thus, average reliability levels. Ilorin, Ikeja, Kaduna and Kano distribution systems have percentage average relative CAIDls of 11.95%, 39.76%, 40.17% and 41.08% respectively with poor reliability levels. With the aid of curve fitting (cf) tools, two distinct model equations were developed from which a generalized model is formulated for a quantitative evaluation of reliability indices of the national grid. The generalized model is a polynomial function whose order depends majorly on the level of industrialization of the distribution systems and the number of distribution feeders. 2 results 2
- " Flow variability of ephemeral rivers due to spatial and temporal distribution of rain fall and unregulated exploitation of water resources is a major cause of severe water supply shortages. With appropriate conservation planning of surface waste resources through hydrological modeling, timing of extraction of large volume without adverse effects on downstream requirement can be predicted. This study attempts to develop water balance components for evaluating flow characteristics essential for conservation planning of ephemeral streams. Daily meteorological data spanning 1973-2006, obtained from the International Institute of Tropical Agriculture, Ibadan weather station were used in developing predominant water balance model components of Ona Stream. Daily infiltration values were obtained using Crawford and Linsley’s model and interflow based on soil moisture levels. Data were statistically analyzed and developed models validated using 10 years meteorological data. Analyses showed that 93.4, 91.5 and 55.0 % variability in runoff was due to precipitation, groundwater storage and interflow respectively. Precipitation, interflow and groundwater storage were significant while evapotranspiration was insignificant (P.0.05) for runoff prediction. The water balance models simulated acceptable hydrologic processes such as interflow and groundwater storage which are generally difficult to measure directly. The R2 values obtained from validation range from 0.79 to 0.99. The water balance model thus improved the reliability of streamflow computation and other flow characteristics of the ephemeral Ona stream. It would appear that the ephemeral streamflow investigated depended more on the magnitude of precipitation interflow and groundwater flow while evapotranspiration (a major source of water loss in hydrologic water balance model) has relatively little effect on streamflow characteristics." 1 results 1
- "Agricultural water management system aims to provide crop water requirement to sustain optimum yield. Some of the factors influencing optimum crop yield are drainage design parameters in water logged soils. Hence, the impact of drainage design parameters on optimum crop yield was examined, field experimentation was for 12 weeks which includes land preparation, planting to maturity of Corchorus olitorius ('Ewedu') on a poorly drained sandy loam of National Horticultural Research Institute, Ibadan 'fadama' field. Hourly rainfall and daily minimum and maximum temperature data for 32 years (1963-1994) for Ibadan was obtained from Nigerian Meteorological Station as DRAINMOD input data. Aluminum drainage pipes at 110cm drain spacing, 60cm drain depth and effective radius of 5.08cm was installed. Depth from drain to restrictive layer was 204.3cm while drainage coefficient was 1.3cm/day. Drainage system parameters, such as grain spacing, drain depth, effective drain pipe radius were varied and effects on crop yield observed. Field evaluation was conducted at 60cm and 110cm drain depth and spacing respectively, and relative crop yield of 36.39% was attained at 40cm, 45cm, and 55cm drain depth, corresponding to 120cm, 115cm and 105cm spacing respectively when drain depth was varied with drain spacing at constant drain pipe effective radius it was concluded that if land availability is limiting and there is availability of cheap labour typical of developing countries drain depth of 55cm, and drain spacing of 105cm and drain pipe effective radius of 2.54cm (i.e 1 inch pipe) corresponds with the optimum yield of Corchorus olitorius. However, shorter drain spacing requires more drainage pipes and land reformation; hence increase in production cost. " 1 results 1
- A 40-year-old woman was diagnosed as having stage II squamous cell cervical carcinoma and managed with radiotherapy. Three months after treatment, she presented with features suggestive of an advanced ovarian tumour including gross abdominal swelling, bilateral ovarian tumours, multiple tumour seedlings in the abdominal cavity and ascites. There was also pleural effusion. Operative findings revealed widespread intra-abdominal metastases whose histology, contrary to expectations, showed squamous cell carcinoma of cervical origin. Distant metastases from squamous cell carcinoma of the cervix are rare. A high index of suspicion is necessary to detect this unusual mode of presentation. 1 results 1
- A previous paper on developing a national capability for the manufacture of activated carbon from agricultural waste by the same authors was considered. In the said paper, the process flow diagram for the manufacture of Granular Activated Carbon from three agricultural wastes namely coconut shell, oil-palm shells and sugarcane bagasse was provided and the plant’s economic analysis done. The objectives of this study were to investigate selling price reducing options and profitability of the investment discussed. In the study, the profitability indexes for the overall plant projects for the three plants were found. The effect of equipment cost reduction on the total productive cost was also examined. For the steam activation of coconut shell, successive reduction by 10% in the overall equipment cost was found reduce the corresponding Product cost geometrically by values ranging from 2.44-1.22% for ten successive reductions. The profitability index was between 0.057 and 4.07% respectively for the 1st to the 11th year. The steam activation of sugarcane bagasse was different, successive reduction by 10% in the overall equipment cost reduce the corresponding Product cost also geometrically by values ranging from 2.85-3.69% (increasing with each reduction) also for 10 successive reductions. The profitability index was between 0.09 and 3.7% respectively for the 1st to the 11th year. And for the phosphoric activation of oil-palm shell, successive reduction by 10% in the overall equipment cost was found reduce the corresponding Product cost geometrically by values ranging from 4.58-2.88% (decreasing with each reduction as in steam activation of coconut shells). The profitability index was between -1.08 and 2.12% respectively for the 1st to the 11th year. In addition, an excel software to simulate the economic analysis previously done and output the key costs after the simulation. 1 results 1
- AODV 1 results 1
- Abdominal extrapulmonary tuberculosis (EPTB) responds well to medical treatment. The cases present with features which may be non-specific simulating other diseases like ovarian cancers leading to unnecessary surgery. The EPTB is common among HIV-TB co-infected population. We report cases of abdominal EPTB among 2 HIV positive women mimicking cancer of ovary. Case one was a 41-year-old multiparous HIV positive woman with painless abdominal swelling of a month. Abdomen was distended with ascites and palpable abdominopelvic mass of about 14 weeks size confirmed as a right ovarian 9.8cm x 8.2cm mass on ultrasonography. Investigations showed marked lymphocytosis and CA-125 value of 1095 U/ml. Intraoperatively, there was widespread peritoneal and omental military nodules with adhesion of the colon with the uterus. Histology of specimen showed caseating granulomatous lesion with necrotizing inflammation and cytology of ascitic fluid showed admixture of neutrophil polymorphs, lymphocytes, and macrophages with no malignant cells. She had antituberculosis and responded satisfactorily to the treatment. The second case was a 50-year-old grand-multiparous with recurrent abdominal swelling one month after surgery for suspected ovarian cancer in a private hospital. The histology of surgical specimen did not show malignant cells. The abdomen was distended with ascites and firm irregular 12-14 weeks suprapubic mass confirmed from ultrasonography as a left adnexal complex mass. The Mantoux test and HIV screening were positive. She was treated with antituberculotic and antiretroviral drugs with satisfactory improvement. Conclusion: With the high prevalence of HIV-TB co-infection in our environment, the possibility of abdominal tuberculosis should be considered in HIV positive patients with abdominal mass. This diagnosis should be high in our differentials and use of ancillary investigations can be helpful in resolving this diagnosis to avoid unnecessary surgical interventions. 1 results 1
- Abdominal tuberculosis 1 results 1
- Aim: To describe a rare case of pelvic desmoid tumour simulating as a huge uterine leiomyoma causing a diagnostic dilemma in a premenopausal woman. Case Presentation: This was a 44-year-old, para 2 (2 alive) who was referred to our gynaecology clinic from a secondary health facility on account of slowly increasing abdominal swelling of 2 years Case Report Ajani et al.; JAMMR, 32(2): 94-99, 2020; Article no. JAMMR.54612 95 duration. There was no nausea, vomiting or diarrhoea. There was associated mild to moderate dull lower abdominal pain that did not radiate to any other part of the body. There was no change in her monthly menstrual flow. Physical examination revealed a pelvic mass about 32 weeks pregnancy size and firm. Computed Topography scan showed a huge pedunculated sub-serous uterine fibroid. A huge mass adherent to the anterior surface of the body of the uterus was completely surgically excised at exploratory laparotomy. Histology of the excised tumour revealed a definitive histological diagnosis of pelvic desmoid tumour. The patient was clinically stable and discharged home 10 days post operation and was followed-up on out-patient gynaecology clinic basis. Discussion: Pelvic desmoid is a rare mesenchymal tumour caused by abnormal proliferation of fibroblasts. It is three times more common in women and occurs mostly between 25 and 35 years of age which correspond to the same age peak incidence for uterine fibroids. The tumour can easily be misdiagnosed as uterine leiomyoma and imaging cannot reliably distinguish the two conditions. Conclusion: Pelvic desmoid tumour should be considered as a differential diagnosis in premenopausal women who present with abdominal swelling. Relevant clinical history, Radiological imaging and Histopathological assessment are essential in making prompt accurate diagnosis. 1 results 1
- Air-conditioning system design and ducting analysis has over the years been an aspect of Engineering, which even though has developed greatly, yet it brings about very tedious tasks of analysis, low level of accuracy, and a lot of time input in carrying out its analysis manually. This work makes provision for the use of a software package, designed for ducting analysis. It has the capability of handling analysis for buildings having as much as nine (9) floors, with each floor having up to twenty (20) rooms. The report gives an account of the method used and the programming aspect of the package for ducting analysis. The thermal analysis of a building forms the basis for the equipment selection in terms of capacity of the cooling equipment, quantity of dehumidified air required and the type of system to be recommended. The estimated air quantity is then used in carrying out the analysis of the system. The package has been designed in such a way that results of analysis made could be printed out for use. Also, it can be easily used on any computer that has a floppy drive for its installation, and has been produced using Visual Basic 6.0. it would be very useful for professionals, as it can carry out analysis which might take hours to develop in few seconds, and also, can be used in higher institutions as teaching aid to INSTRUCT Engineering students. 1 results 1
- Autocorrelation plot 1 results 1
- Babcock University 1 results 1
- Background/Aim: Iatrogenic tooth damage is a well recognized and longstanding problem that appears to have refused to disappear from restorative clinical practice. This study was designed to determine the pattern of distribution of iatrogenic tooth surface damage caused by a cross section o f dental students and residents during Class II cavity preparation in a clinical simulated environment. Methods: Residents rotating through the Department of Restorative Dentistry and randomly selected 1SI year and final year dental undergraduates were told to prepare either mesio-occlusal or disto-occlusal Class II cavity on pre-selected normal upper plastic posterior tooth mounted on phantom head after obtaining inform consent. The type of preparation that is selected is based on the adjacent tooth surface that is intact. At the end, the location of the damage and the type (Groove; indentation; Scratches; Extensive) as described by Medeiros and Seddon (2000) was evaluated under a magnifying lens. Summary statistics was generated. Results: The frequency of iatrogenic tooth damage was 100% and “indentation” was the commonest pattern, followed by grooves. More damages occurred in the cervical area. Extensive damage formed 19.0% of the total damages and this type of damage was found more adjacent to MO cavity (25.0%) compare to DO (15.4%) but there was no difference between the extensive damage that occurred on the right and left sides. Conclusion: The frequency of iatrogenic tooth damage was 100% and indentation was the commonest pattern. Extensive type of damage was found more adjacent to MO cavity. 1 results 1
- Background: Unresolved drug therapy-related problems (DTRPs) have economic and clinical consequences and are common causes of patients’ morbidity and mortality. This study evaluated the ability of community pharmacists to identify and resolve DTRPs and assessed the perceived barriers to DTRP identification and resolution. Methods: A cross-sectional study which employed the use of three simulated patients (SPs) visit to 36 selected community pharmacies in 11 local government areas in Ibadan, Nigeria. The SPs played the role of a patient with prescription for multiple ailments (23-year-old male), type 2 diabetes and hypertensive patient with medication packs (45-year-old male) and hypertensive patient with gastric ulcer with a prescription (37-year-old female). They reenacted three rehearsed vignettes when they spoke with the pharmacists. A five-member panel of experts predetermined the DTRPs present in the vignettes (n = 11), actions to take to investigate the DTRPs (n = 9) and recommendations to resolve the DTRPs (n = 9). Pharmacists’ perceived barriers to the identification and resolution of DTRPs were assessed with a self-administered questionnaire. The percentage ability to detect and resolve DTRPs was determined and classified as poor ability (≤30%), fair ability (> 30 - ≤50%), moderate ability (> 50 - ≤70%) and high ability (> 70%). Results: One hundred and eight visits were made by the three SPs to the pharmacies. In total, 4.42/11 (40.2%) DTRPs were identified, 3.50/9 (38.9%) actions were taken, and 3.94/9 (43.8%) recommendations were made to resolve the identified DTRPs. The percentage ability of the community pharmacists to detect and resolve DTRPs varied slightly from one vignette to another (vignette 1–49.3%, vignette 2–39.1%, vignette 3–38.8%). But overall, it was fair (40.9%). Pharmacists’ perceived barriers to DTRP detection and resolution included lack of access to patient’s/client’s medical history and lack of software for DTRP detection. Conclusions: The community pharmacists displayed fair ability in detecting and resolving DTRPs. Several barriers preventing the optimal performance of pharmacist in DTRP identification and resolution were identified including inaccessibility of patient’s/client’s medical history. The regulatory authority of pharmacy education and practice in Nigeria need to mount Continuing Education Program to address this deficit among community pharmacists. 1 results 1
- Basic Science 1 results 1
- Basic Science is a core subject at the basic education level in Nigeria. It is taught to lay foundation for future subjects, such as Biology, Chemistry and Physics. Evidence abound that students dislike, fear and therefore fail the senior secondary science subjects due to inadequate exposure to practical works and skills at the basic education level. Previous studies largely focused on factors affecting teaching and learning of Basic Science practical without emphasis on intervention through regular conduct of laboratory experiments in the subject. This study, therefore, determined the effects of Simulated Laboratory (SL) and Enriched Laboratory Guide Material (ELGM) experiments on students’ achievement and acquisition of Science Process Skills (SPS) in Basic Science in Oyo State, Nigeria. The moderating effects of gender and future career interest in science were also examined. Bruner’s constructivist and Kolb’s experiential learning theories provided the framework, while the pretest-posttest control group quasi-experimental design with a 3x2x2 factorial matrix was adopted. Three local government areas were randomly selected from each of Ibadan (Ibadan South-East, Ibadan South-West, Ibadan North) and Oyo (Afijio, Oyo-East, Oyo-West). Six co-educational public secondary schools were purposively selected based on availability of functional computer and science laboratories. Six randomly selected intact classes of junior secondary three students (130 males and 147 females, ±17 years) were randomly assigned to SL (110), ELGM (60) and Conventional (Expository) Laboratory - CEL (107). The instruments used were: Achievement test in Basic Science (r=0.87), Science process skills test in Basic Science (r=0.72) and Future career interest in Science questionnaire (r=0.99). The treatments lasted seven weeks. Data were analysed using Analysis of covariance and Scheffé post-hoc test at 0.05 level of significance. Treatments had significant main effect (F(2,264)=25.88; partial η2=.16) on students’ achievement in Basic Science. Participants in the ELGM group had highest achievement mean score (24.91) followed by CEL (24.77) and SL (19.40). Future career interest in science had significant main effect (F(1,264)=4.08; partial η2=.02) on students’ achievement in Basic Science. Participants in the Science-Related (SR) group had higher achievement mean score (23.87) than Non-Science Related (NSR) group (22.18). Treatments had significant main effect (F(2,264)=25.51; partial η2=.16) on students’ acquisition of SPS in Basic Science. Participants in the SL group had highest SPS mean score (15.00) followed by ELGM (14.66) and CEL (12.59). Future career interest in science had significant main effect (F(1,264)=17.62; partial η2=.06) on students’ acquisition of SPS in Basic Science. Participants in the SR group had higher SPS acquisition mean score (14.81) than NSR (13.36). There was no significant main effect of gender on students’ achievement and acquisition of SPS in Basic Science. There were no significant two-way and three-way interaction effects on students’ achievement and acquisition of SPS in Basic Science. Enriched laboratory guide material experiment was more effective in enhancing achievement while Simulated laboratory experiment was more effective on acquisition of science process skills. The two modes of laboratory experiments should be adopted for improved achievement and acquisition of science process skills in Basic Science 1 results 1
- CA125 1 results 1
- CROPWAT-8 Model, 1 results 1
- Cervical carcinoma 1 results 1
- Changes in age structure that results from demographic transition have economic consequences. This paper identifies the period of potential window of opportunity or demographic dividends created by Nigeria’s demographic transition. This is done by simulating the period of the demographic window of opportunity in Nigeria. In a simulation covering 1950 – 2050 our results reveal that Nigeria entered the window of opportunity in 2003 and will last beyond year 2050. The highest benefit will accrue in years 2032 and 2033 when the dividend can account for more than 10% of the growth of GDP per capita even if the current performance scenario continues to exist. However, the paper notes that the demographic dividend is not automatically realized and Nigeria needs to embark on strategies that will develop her human capital and position her towards not only capturing the first dividend but the second dividend as well. 1 results 1
- Chloride concentration 1 results 1
- Class 1 results 1
- Coastal aquifer 1 results 1
- Commodity price shocks Social accounting matrix 1 results 1
- Computable General Equilibrium Model 1 results 1
- Cropwat-* model, 1 results 1
- DRAINMOD 1 results 1
- Demographic dividends 1 results 1
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- SUNScholar — Stellenbosch University Repository 259 results 259
- UCTD — University of Cape Town Open Access Repository 214 results 214
- UPSpace — University of Pretoria Institutional Repository 150 results 150
- AUC Knowledge Fountain — bepress 21 results 21
- KNUSTSpace — Kwame Nkrumah University of Science & Technology (Ghana) 6 results 6