Natural Sciences

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A spartial framework for managing sewer and water networks using sensor networks: a case of the university of Zambia.
(The University of Zambia, 2023) Chibuye, Gabriel
Public institutions generally have a lot of facilities and infrastructure catering for the population of the institution. Some important infrastructure such utilities which include water, sewer, electricity, and telecommunications require constant maintenance, management, and adequate monitoring for them to function effectively. This study aimed to build a framework for Managing Sewer and Water Networks Using Sensor Networks at the University of Zambia. The methodology involved understating the existing operations of the Resident engineer’s office to ascertain the user needs. These needs formed the basis of the study, the development and design of the prototype of the Web based Framework. Data Collection was done using various methods. A presurvey (Reconnaissance Survey) was done to have an idea of the existing infrastructure and a more accurate survey was done using GPS GNSS equipment GIS software was used to process data and create shapefiles. A 15-digit coding system was created and was used to assign unique identification numbers and extra attribute information to the water and sewer network shapefiles. A QR code was generated for each node and the serial number recorded. Tagging was done using the QR code for each structure. All the shapefiles were loaded into a PostGreSQL spatial database and were used as input in the Web GIS application. The web application had some tools imbedded in it which were mainly for monitoring and management of the structures. Using internet of things (IOT) technology, water level sensors were placed in a prototype to mimic some critical manholes to help with the monitoring of the sewerage network. The system could therefore be used for identification of any infrastructure by scanning the QR code and a map showing the structure would be seen online by the field technicians. Students could also be able to send out notifications to the resident engineer in case there was a damaged or malfunctioning structure. Monitoring of the sewer system could be done using the sensors and ultimately the framework would ease the management of the water and sewer systems at the University of Zambia.
A framework for an early warning system for the management of the spread of locust invasion based on artificial intelligence technologies.
(The University of Zambia, 2024) Halubanza, Brian
As the global population continues to grow, ensuring food security remains a paramount challenge, especially in light of threats like devastating locust invasions. The agricultural sector in Zambia, particularly in the Sikaunzwe area of Kazungula district, Southern Province, faces unique challenges including inaccurate locust species identification, a lack of field staff, and the inaccessibility of infested areas. Despite advancements in AI and sensor applications for pest management, existing approaches often fail to robustly adapt to varied agronomic conditions or to integrate real-time environmental data effectively. Furthermore, these methods generally lack sufficient engagement of local communities, crucial for the sustained success of locust management strategies. This research addresses these problems by introducing a comprehensive framework that enhances early warning and management of locust invasions. The methodologies employed include Focus Group Discussions (FGDs), semi-structured questionnaires, and field experiments using a Deep Learning model embedded in Internet of Things (IoT) devices and Cloud Computing. The research is guided by the Unified Theory of Acceptance and Use of Technology (UTAUT) and the Design Science Research Methodology, facilitating systematic development and evaluation of an AI-based early warning system. The development of mobile applications and SMS services has significantly enhanced the reach and effectiveness of locust management strategies. The research culminated in the creation and implementation of an advanced Convolutional Neural Network (CNN) model, specifically the MobileNet version 2 quantized model, tailored for automatic identification of locust species. This model achieved an average precision rate of 91% for Locusta migratoria and 85% for Nomadacris septemfasciata using a custom dataset of 1700 images from the study area. Beyond AI-driven identification, the research integrated low-cost IoT devices capable of capturing real-time locust images and uploading them to an online database only if they met an 80% accuracy threshold, while also collecting vital environmental data like temperature and humidity. This integration of AI, IoT, and real-time data collection represents a transformative approach to integrated locust pest management, setting a scalable model for future adoption in similar agricultural contexts. The framework not only addresses immediate locust management challenges but also enhances the broader path of technological progress in agriculture.
A model of the hydrogen atom for l = 1 and l = 3 using the causal interpretation.
(The University of Zambia, 2025) Chiboli, Monica
This study presents a model of the hydrogen atom for the orbital angular momentum l = 1 and l = 3 using the causal interpretation also referred to as the Bohm-de Broglie interpretation of quantum mechanics. The causal interpretation is an alternative interpretation of quantum mechanics that gives a description of underlying physical reality in terms of a single well-defined model which Bohr’s principle of complementarity claims to be impossible. This study presents detailed analytical calculations to determine the electron trajectories for the hydrogen atom states ψ21m and ψ43m. Further analytical calculations were made to determine the net force and magnitude of the angular momentum. The model was also extended to determine the trajectory of the rotated wave function. This was done both analytically and numerically using Maple. Maple was also used to plot the trajectories, net force, and angular momentum. The obtained results show that electrons have definite circular paths which are a result of the net force which is always directed to the z-axis. The results for the angular momentum show consistency with quantum mechanics, as the plots show that the angular momentum vector at various positions of the electron for a given value of m form a cone shape in its movement. The results also show that the electron is stationary form = 0, but rotates anti-clockwise for positive values of m and clockwise for negative values of m. From this work, it can be seen that the causal interpretation can be used to make models of quantum experiments/processes. This research therefore brings new light to the behaviour of an electron in atomic systems, thereby making contributions on the effort to develop a physical reality of quantum systems with implications in quantum chemistry and quantum physics. The presentation of this model also shows the effectiveness of Maple in developing computer models, especially in science and mathematics. Keywords: Causal interpretation, trajectories, wave function, Maple, hydrogen atom, net force, angular momentum.
A multivariate poisson integer-valued autoregressive model for public health surveillance.
(The University of Zambia, 2025) Zulu, Zielesa
This dissertation develops a first-order multivariate Poisson integer-valued autoregressive (MPINAR(1)) model to improve disease outbreak detection in public health surveillance systems. The MPINAR(1) model is proposed as a computationally tractable alternative to the general multivariate integer-valued autoregressive (MINAR(1)) model. While the MINAR(1) framework allows for correlated innovations, it introduces substantial estimation challenges and requires strong distributional assumptions that may not hold in practice. To address these limitations, the MPINAR(1) model simplifies the innovation structure by assuming that the innovation process consists of independent Poisson-distributed components. This assumption retains the discrete nature of the data while reducing computational complexity, allowing for efficient implementation using conditional maximum likelihood estimation. A simulation study is conducted to evaluate the performance of the MPINAR(1) model in detecting simulated outbreaks within trivariate count time series. The model is assessed against independent univariate INAR(1) models using metrics such as average run length (ARL), detection rate, and false alarm rate (FAR). Results show that the MPINAR(1) model outperforms the univariate alternatives, particularly in scenarios involving moderate to large outbreak sizes. The model is further applied to syndromic surveillance data comprising daily counts of fever, cough, and dyspnea among hospitalised COVID-19 patients. Covariate adjustments for dayof-week and seasonal effects are incorporated into the innovation process. The MPINAR(1) model demonstrates superior fit compared to univariate models, producing wider and more reliable prediction intervals and detecting additional potential outbreak events. Residual analyses confirm that the MPINAR(1) model provides a closer approximation to white noise and better captures temporal and cross-sectional dependencies. Overall, the MPINAR(1) model provides a theoretically sound and computationally efficient framework for multivariate count time series modelling in surveillance settings. Its improved detection capabilities and robustness to overdispersion make it a valuable tool for enhancing early warning systems in public health. Future extensions could include more flexible innovation structures and refined alarm decision rules.
A negative binomial ingarch model for overdispersed count time series structure, parameter estimation and application to real data.
(The University of Zambia, 2025) Mulamfu, Carols
This dissertation develops a negative binomial integer-valued generalized autoregressive conditional heteroscedastic model of order p, q (negative binomial INGARCH(p, q)) for overdispersed count time series data with potential extreme values. The model is formulated such that its conditional distribution follows the negative binomial distribution, allowing the conditional variance to exceed the conditional mean and dynamically adjust for overdispersion based on past observations. Furthermore, the unconditional variance exceeding the unconditional mean demonstrates the model’s capability to capture extreme values in the data. A simulation study evaluates the finite sample performance of the Yule–Walker, conditional least squares, and maximum likelihood estimation methods for the three sparsely parameterized negative binomial INGARCH(p, q) models. Results indicate that maximum likelihood estimation is the most efficient and reliable approach. The conditional log-likelihood function is maximized numerically using MATLAB’s fmincon function, with constraints to ensure stationarity and non-negativity of parameters. Conditional least squares estimates serve as initial values to facilitate convergence and enhance stability. For application, the negative binomial INGARCH(p, q) model is applied to syphilis count data from the R ZIM package, originally sourced from the CDC Morbidity and Mortality Weekly Report CDC MMWR. The dataset consists of weekly syphilis cases in Maryland, United States, from January 2007 to May 2010, with 209 observations. The empirical mean (3.47) and variance (9.28) confirm overdispersion, justifying the use of the negative binomial distribution. Model performance is assessed and compared to the Poisson INGARCH(p, q) and double Poisson INGARCH(p, q) models using the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). Additionally, tail probabilities of residuals are analyzed to evaluate the models’ ability to capture extreme values. Results from AIC, BIC, and tail probability analysis indicate that the negative binomial INGARCH(p, q) model outperforms the Poisson INGARCH(p, q) and double Poisson INGARCH(p, q) models.
A pilot study to identify single nucleotide variants in exon 19 of the braca1 gene in female breast cancer patients at Matero level one hospital, Lusaka, Zambia.
(The University of Zambia, 2022) Shakachite, Lisa
Breast cancer (BC) patients in Zambia more commonly present with advanced-stage disease and often at young ages (≤50 years). Breast cancer gene 1 (BRCA1) is a tumor suppressor gene in which mutations have been linked to disease presentation at a young age. More than 600 distinct pathogenic (disease causing) single nucleotide variants with the potential for structural and functional effects on BRCA1 have been documented in ClinVar, a major human variation and phenotype database. The BRCA1 C-terminal (BRCT) region is critical for tumor suppression because it acts in DNA damage repair and cell cycle checkpoint protein control. Mutations in this region have been associated to structural effects and loss of function of BRCA1 in many studies. However, BRCT mutations in young female breast cancer patients from Zambia have not been identified to date. The genetic alterations in exon 19 of the BRCA1 gene were assessed here for the first time in a cohort from Zambia. Seventy-three patients diagnosed with breast cancer at the age of ≤50 years were recruited irrespective of family history of breast and/or ovarian cancer. Genomic DNA was extracted from ten peripheral blood samples and PCR-amplified with exon 19-targeting primers of the BRCA1 gene. Amplicons were sequenced using a Sanger sequencing platform and analyzed using bioinformatics tools at various web-based platforms and ClinVar. Overall, elevensingle nucleotide mutations were identified in three patients, and all known to play a role in determining the structure of BRCA1. Of the identified mutations, one was pathogenic and sevenhad uncertain significances. Six of these mutations were heterozygous and classified in the loss of function category in ClinVar. These variants were specifically associated with Breast-ovarian cancer, familial, susceptibility to, 1 (BROVCA1). Four out of the six heterozygous mutations were missense mutations and two were nonsense mutations. Based on an unpaired two-tailed student’s t-test, the null hypothesis that there was no association between the age of a BC patient and the number of mutations in exon 19 leading to a loss of function of BRCA1, was rejected (P= 0.04). Further studies are clearly necessary to explore how mutations in the entire BRCA1 gene affect disease presentation in the female BC population. The young age (≤50 years) for breast cancer diagnosis in female Zambian patients may be attributed to other factors like other genetic mutation status, epigenetic changes, lifestyle etc. These results will help in decision making with regard to the integration of genomic medicine into breast cancer care in Zambia which has tremendous potential to improve the outcomes and survival of diagnosed patients.
A web based document archiving system using indexing and machine learning for research and innovation grant allocation.
(The University of Zambia, 2024) Lupyani, Rebecca
In today’s rapidly evolving world, research forms a cornerstone of human progress leading to new products, services, and technologies, which, in turn, can stimulate economic growth and enhance the quality of life. Research enables people to learn, innovate and address the complex challenges facing a society. It is a powerful tool for making the world a better place and as such many countries endeavor to support the research landscape by providing research grants in different sectors. The process of allocating research grants plays a pivotal role in fostering scientific progress, innovation and knowledge. The traditional manual selection of grant proposals, while well-established can be resource intensive time-consuming, subjective, and prone to bias. This paper presents an unconventional strategy that leverages machine learning algorithms to enhance the fairness, efficiency, and transparency of the grant allocation process by removing human biases and prejudices that can inadvertently influence funding decisions. The study discussed the design and implementation of a machine learning-based grant allocation system using historical grant data from a reputable funding agency and provided empirical evidence of its effectiveness by selecting the best performing text classification algorithm from a comparative analysis of three models and integrating it into a web based application. The three models compared were the K- Nearest Neighbour, the Naives Bayes and the Support Vector Machine. The Support Vector Machine exhibited the highest performance metrics with an accuracy percentage of 88%, precision of 86%, recall of 87% and F1 score of 87%, whereas the K-Nearest Neighbour portrayed the lowest performance with an accuracy of 41%, precision 52%, recall of 43% and F1 score of 37%. Thus, the Support Vector Machine was integrated into a web based application to facilitate fund allocation. The developed system will promote fair review of research and innovation proposal applications by automatically categorizing them into topic categories that facilitate funding such as engineering, science and technology. The system will also assist in tracking and monitoring the progress for the research projects for which funding institutions invest in and also in digitally archiving the documents in an effective and efficient manner
Abudance,growth and reproductive biology of oreochromis niloticus (Linneaus,1758)compared with tilapiines indigenous to the middle Zambezi
(The University of Zambia, 2017) Nyirenda, Steinslaus Masuzyo
The introduction of Oreochromis niloticus on Lake Kariba has been widely associated with the decline in preponderance of indigenous Tilapiines, especially Oreochromis mortimeri. Comperative aspects of abundances, growth and reproductive biology for O. niloticus, and three known indigeous Tilapiines: Oreochromis andersonii, Oreochromis mortimeri, and Tilapia rendalli were investigated. The study was conducted at the riparian Sinazongwe District of Southern Zambia from August to September, 2014. Weight, length and reproductive stages of the different Tilapiine fish were determined. The morphometric and age data was used to determine growth parameters for the Tilapiines using Von Bertalanffy Growth Function (VBGF). Whole ovaries from sexually mature females (ripe and/ or ripe-running) were weighed and preserved in 5% formalin solution; fecundity was determined using gravimetric procedures. Analyses of Variance (ANOVA) were applied in comparing statistical significances in abundance, growth and reproductive parameters among the studied Tilapiines. Detailed contribution by weight and number for each Tilapiine species at Sinazongwe indicated dominance of O. niloticus (IRI=8.62%) whereas T. rendalli accounted for 0.77%. Oreochromis andersonii and O. mortimeri made insignificant IRI contributions (<1%). Investigation into dependence of Tilapiine abundance on intrinsic growth rate, (K) indicated a positive linear relationship defined by a statistically insignificant regression equation: Abundance=92.49K-8.39 (R2 =0.94; p>0.05). Specimens collected ranged in age from 2-6 years. The intrinsic growth rate, K, was highest in T. rendalli (0.791yr-1), followed by O. mortimeri (0.308yr-1), O. niloticus (0.180yr-1) and least in O. andersonii (0.147yr-1). Growth performance indices (Φ') for the species differed marginally, being highest for T. rendalli (4.98) and O. niloticus (4.58), and moderately lower in O. mortimeri (4.57) and O. andersonii (4.36). There were significant differences (p<0.05) observed on the fecundities among the studied female Tilapiines. Tilapia rendalli had highest average number of oocytes, 5,135. Among the Oreochromis species, O. niloticus had an average 2,923 oocytes whereas O. andersonii had 1,650 oocytes. On the other hand, O. mortimeri had the lowest fecundity, 994 oocytes. Oreochromis niloticus was the most abundant Tilapiine at Sinazongwe, and indeed an established species throughout Lake Kariba, on the Zambian shoreline. The studied characteristics among the Tilapiines indicated that O. niloticus was not superior in every aspect of its growth and reproductive biology.
Acaricide resistance in Rhipicephalus appendiculatus Neumann, Amblyomma Variegatum (Fabricius) and Boophilus decoloratus (Koch) in Southern and Central Provinces of Zambia
(2012-08-20) Luguru, Stephen M. K.J
Acaricide resistance tests were conducted on 14-21 days old larvae of Rhipicephalus appendiculatus Neumann, Amblyomma variegatum (Fabricius) and Boophilus decoloratus (Koch), using the Food and Agriculture Organization (FAO) Acaricide Resistance Test Kit, and acaricide test papers prepared locally according to the FAO method. Engorged female ticks for larval production were collected from different localities in the Southern and Central (including Lusaka) Provinces of Zambia. The lowest LC50(%) values obtained from sets of data for each tick species were used to calculate resistance factors (RF).The range of LC50(%) values for R. appendiculatus and for B. decoloratus in brackets using the FAO Kit were: cypermethrin, 0.025-0.30 (0.03-0.045), coumaphos, 0.13-0.60, dioxathion, 0.20-0.60 (0.35-0.60), diazinon, 0.03-0.13 (0.015-0.06) and dieldrin, 0.08-0.30. For local papers values were: cypermethrin, 0.026-0.260 (0.012-0.056), chlorfenvinphos, 0.02-0.08 (0.012-0.12), dioxathion, 0.062-0.47 (0.03-0.50) and deltamethrin, 0.005-0.015 (0.004-0.011). For A. variegatu/n values with the FAO Kit and values with local papers in brackets were: dioxathion, 0.15-0.26 (0.032-0.32), cypermethrin, 0.03-0.082 (0.01-0.084), dieldrin, 0.05-0.32 and chlorfenvinphos (0.011-0.052). These results indicated that cattle ticks in the Southern and Central Provinces of Zambia are developing resistance to acaricides. B. decoloratus in the commercial sector and R. appendiculatus in the traditional sector showed resistance to a number of acaricides whereas Amblyomma variegatum showed resistance to dieldrin and dioxathion. Boophilus decoloratus from the traditional sector were however, relatively susceptible. The observed pattern of resistance is attributed to a number of factors such as the frequency of acaricide application, cattle management and type of cattle and other agricultural and ecological factors. Although cypermethrin and dioxathion were the only acaricides which were both in the FAO Kit and locally prepared test papers, results obtained showed some agreements between the two types of test papers. From the results, it is possible to identify resistance using local papers on the same lines as would be with the FAO papers. Since chemical control of ticks is the most practical method of controlling ticks and tick-borne diseases in Zambia, the usage of acaricides should be carefully monitored to avoid development of multiple resistance in tick populations. Although locally prepared papers have their limitations, it is important to note that they may be a useful tool in enabling economically poor countries like Zambia to detect early resistance in ticks in the absence of the standardised FAO Resistance Test Kit. An integrated approach to tick control involving less use of acaricides is discussed.
Access and control over agricultural income and labour in smallholder farming systems: a gendered look from Chipata, eastern Zambia.
(The University of Zambia, 2019) Pelekamoyo, Joan
This study sought to investigate access to and control over agricultural income and labour in smallholder farming households in Chipata district, Zambia. The objectives were to investigate the agricultural practices employed by smallholder farming households in Msandire and Mkanda areas of Chipata District, investigate decision making over agricultural income by men and women in Msandire and Mkanda smallholder farming households and examine the gendered aspects of household labour allocations among smallholders in Msandire and Mkanda agricultural camps. Methods of data collection that were used in this study included household and key informant interviews, focus group discussions and a desk analysis of publications on gender in agriculture. The HAF was used to identify the roles and assess the access to and control over agricultural resources by men and women farmers in the study area. Descriptive analysis such as means and percentages were used to analyse quantitative data, while qualitative data from the focus group discussions, the key informant interviews, and answers to the open-ended questions of the semi-structured interviews were analysed using content analysis. Results show that agricultural practices which were commonly employed by smallholder farming households were flat culture being the most practiced tillage by both male-headed households (71%) and female-headed households (91%). Ploughing was more common among the households headed by men (16%) and in households headed by women, it only occurred in 7%. Then ripping only occurred in male-headed households with none of the women ripping their fields. Only men had access to and control over cattle resulting in a high prevalence of women using the flat culture system due to limited access to draught animals. Decisions were made jointly in male-headed households (48%) over agricultural income while for female-headed households, joint control occurred only in 19% of the cases. The most frequently made joint decisions concerned harvesting, planting, and crop sale. Over half (58%) of the women in female headed households controlled their household‟s agricultural income as compared to only 15% of women in the male-headed households. In the male-headed households only 37% of the men controlled their agricultural income as compared to 23% of the men in the female-headed households. Men allocated most of the labour activities in the male-headed households and women only took charge in the absence of men or in female-headed households. Both men and women in male and female-headed households were involved in manual weeding and harvesting. This study concludes that women generally have access to agricultural resources but do not have control over them. Mostly men have control unless in households where the woman is the head of the household. Hence, to ensure equitable access to and control over agricultural income and labour, this study recommends that Government in partnership with the Ministry of Agriculture, NGOs and community based organisations should ensure continued strengthening of gender mainstreaming strategies by identifying and addressing gender inequalities in relation to income and labour resources through the use of gender analysis, and gender-responsive budgeting processes.
Adaptation of Trypanosoma (NANNOMONAS) Congolense broden 1904 types to different hosts and transmission by Glossina species
(2012-09-19) Masaninga, Freddie
The influence of host bLood on midgut infection, maturation rates in Glossina species, transmission and virulence to mice of Trypanosoma congolense DNA types was investigated. The study was also coiKiucted to identify an optimum technique for isolating Nannomonas stocks from the field. Trypanosoma congolense parasites used in this study were identified by the Polymerase Chain Reaction Technique. Zebra and goat blood supported higher midgut and labral infection rates of T. congolense in Glossina morsitans centralis than pig, donkey, black rhinoceros, Thomson's gazelle and eland blood. Of these hosts, zebra supported the h^est metacyclic loads in the hypopharynx. The proportion of midgut infections maturing (transmission index) was generally high for most blood types. It ranged from about 58.0% for tsetse infected with eland blood to 97.0% for tsetse infected with zebra blood. From a practical view point, this study suggests that areas with many goats should have higher infection rates of some T. congolense genotypes. Zebra being a less favoured host probably has a lesser inpact on the infection rates. The pattern of T. congolense Savannah, Kilifi and Riverine / Forest infection rates in G. m. centralis infect«l with goat, black rhinoceros and Boran cow blood was similar during the first 10 days of infection. Rates were highest (up to 90%) on day 3, and dropped 1^ day 5 to reach constant values (ranging from 5% to 45%) by day 10. The 10th day midgut infection rates did not differ significantly from those on day 21 in fifes infected with pig, zebra, goat and eland blood. Carbohydrate binding proteins (lectins) and otter factors are considered to play a role in controlling trypanosoma establishment and maturation. Male G. m. centralis infected with zebra and eland blood matured significantly more gut infections than females. A higher proportion of mice became infected with T. congolense when the infection was initiated by the bite of male tsetse (56.0%) than when the infection was initiated by the bite of a female tsetse (33.0%). This firming was interpreted to suggest an inportant impact on the application of the Sterile Male Technique (SMT) for controlling tsetse flies. Kilifi T. congolense took a significantly shorter tin« to infect mice (13 days) than the Savannah DNA type (18 days). The Kilifi type of T. congolense (K60/1) killed a higher proportion of mice than the Savannah type within 45 days after infection. It also showed earlier parasitaemic peaks than the Savannah type, thus suggesting that the former (Kilifi T. congolense) used in this investigation is nwre virulent than the latter (Savannah T. congolense). Studies on parasite diversity have implications on trypanosomiasis control because they can provide clues to questions on factors that maintain trypanosomes at endemic or factors that can encourage trypanosomes to go into epidemic levels. Trypanosoma congolense (Kilifi type) was detected earlier in mice when the transmitting tsetse was fed on infective goat blood (mean =11 days) than When they were fed on infective eland blood (mean = 14 days). Transmission rates of Kilifi and Savannah types of T. congolense to mice were similar and were not influenced by the host blood type used to infect the transmitting fly. Therefore, the study suggests that host blood can exert host-specific effects on metacyclic devetopment in the tsetse fly that can be subsequently observed when the animal are transmitted with the trypanosomes. Isolation and cloning of trypanosomes by mouse isolation were more effective in Balb/c than Swiss mice. Isolation of T. congolense through gut-form transfer fi-om one tsetse species to another (procyclic expansion technique) was most effective in laboratory reared G. m. centralis and not effective in G. pallidipes and G. m. morsitans. Tsetse passaged with procyclics suspended in fresh goat blood generally survived well during the observation period (survival rates ranged from 58% to 95%). Cholesterol and D(+)-glucosamine added to the goat infective bloodmeal increased infection rates of son» but not all stocks of procyclics. Double cholesterol feeds supported significantly higter midgut infection rates than single cholesterol feeds. Tsetse fed on cholesterol-trypanosome-blood mixtures survived well (survival rates ranged from about 60% to 80%). D(+)-glucosamine facilitated infection rates of procyclics in G. m. centralis but also caused mortality. Pocyclics incubated in different blood mixtures, including cow and goat serum, reconstituted goat red blood cells, heated or unheated, retailed viability for a day at room temperature (25°C.). This suggested that the media used for cryopreserving procyclics was not a critical factor. This study suggests that it is feasible to isolate T. congolense types of trypanosomes by feeding laboratory - reared G. m. centralis tsetse on fresh goat blood and chemical additives such as cholesterol, but maintaining the flies on a rabbit. This finding is discussed in relation to other methods such as the use of G. m. morsitans fed on synthestic diets or the combined use of culture and laboratory reared tsetse flies to isolate T. congolense from wild hosts.
Advancing prostate cancer therapy: synthesis and characterization of docetaxel-loaded magnetic iron oxide nanoparticles for controlled drug release.
(The University of Zambia, 2024) Chisenga, Ian
Prostate cancer is one of the most common cancers among men worldwide, and current drug administration methods of front-line drugs like Docetaxel (DXL) face challenges, including non-specific treatment causing several side effects and the development of drug resistance, which affects patients' response and quality of life during treatment. Hence, there is a need for drug carriers such as Iron oxide nanoparticles, which are suitable for novel drug delivery systems due to low toxicity, biocompatibility, loading capacity, and controlled drug delivery to cancer cells. The purpose of the present study was to synthesize DXL-loaded pegylated magnetic Iron oxide nanoparticles (Fe3O4NPs) for controlled drug release in prostate cancer cells. In this study, Fe3O4NPs were synthesized by the co-precipitation, functionalized with folic acid (FA), loaded with DXL and encapsulated with polyethylene glycol (PEG). Structural analysis was done using ultraviolet-visible (UV-Vis) spectroscopy which showed changes in absorption spectra with each attached molecule a blue shift was observed due to particle size increase. X-ray diffraction (XRD) pattern showed that pure magnetite nanoparticles were synthesized. The Fourier Transform Infrared (FT-IR) results showed a peak at 583, 1089, and 1584 cm-1 these confirmed that Fe3O4 NPs were synthesized. The Langmuir adsorption isotherm model (R2 =0.9947) was favoured over the Freundlich (R2 =0.9441) and Temkin (R2=0.8218). Drug release was faster at a potential of Hydrogen (pH) of 4.8 compared to pH 6.0, 7.0, and pH 7.45 with drug release percentage of 62.4%. 37.8%, 28.3%, and 24.0% respectively after 72 hr. Un-PEGylated Docetaxel-loaded nanoparticles showed a rapid drug release of about 98.8% after 7 hr. Drug release follows the Korsmeyer-Peppas kinetic model (R2= 0.9949) via the Fickian release mechanism. This study showed that Docetaxel-loaded pegylated Fe3O4NPs could be beneficial for increasing the effect of anticancer drugs on cancer cells while minimizing side effects.
Aflatoxin Metabolites in Relation to Protein-Energy Malnutrition in Zambia
(2011-04-05) Samuel, Derina Sara
Findings in the Sudan show a possible association between aflatoxins and kwashiorkor, a category of Protein-Energy Malnutrition (PEM). Similarities in the geographical and seasonal prevalence of aflatoxins and kwashiorkor, as well as similarities in the metabolic derangements caused by aflatoxins and observed in kwashiorkor suggest that aflatoxins may play an etiological role in the pathogenesis of kwashiorkor. Studies in Zambia have shown that aflatoxin contamination occurs in commonly eaten foods, suggesting that the Zambian population is exposed to the toxin. The presence of urinary aflatoxins in patient with and without liver pathology at an incidence which reflects the level of contamination has also been reported. PEM is known to be endemic in Zambia witlva seasonal prevalence similar to that observed with aflatoxin contamination of food. A one-year survey was therefore undertaken to investigate the relationship between aflatoxins and the various categories of PEM. Metabolism of the aflatoxins was determined by analyzing urine and serum samples of PEM cases and appropriate controls from the University Teaching Hospital, Lusaka. As previous studies had shown a higher level of aflatoxin contamination in foods in the Eastern province, urine samples from PEM cases and appropriate controls were obtained from St. Francis1 Hospital, Katete, for comparison. The incidence of urinary aflatoxins in samples from Lusaka and Katete was 6.1 per cent, with a mean concentration of 0.365 ng/ml. Aflatoxin B, and aflatoxicol were detected. Aflatoxicol concentrations were highest in control and lowest in kwashiorkor samples, though aflatoxicol was detected slightly more frequently in the latter. Aflatoxin B, excretion was observed to follow a similar pattern. Comparing the incidences in Lusaka and Katete, a significant difference was not observed. In serum samples the incidence of aflatoxins was 2.8 per cent, with a mean concentration of 1.87 ng/ml. Aflatoxin B, and aflatoxicol were detected with aflatoxicol only being detected in one case of kwashiorkor. Total aflatoxin concentration was higher in kwashiorkor than controls while the incidence was similar in the two groups. The incidence of urinary aflatoxin in the rainy season (18.8 per cent) was greater than in the dry season (5 per cent), however, no significant difference was observed in the seasonal variation of aflatoxins in sera. Urinary aflatoxins were detected more often in males than in females but no significant difference occurred in the sera analyses. The results suggest that there may be certain unusual associations in the incidence, concentrations and type of aflatoxin detected between the different nutritional groups, in particular the role of aflatoxicol in kwashiorkor and the lower excretion levels observed. Possibly this indicates a decreased capacity to deal with aflatoxins. Whether this a cause or an effect of the kwashiorkor syndrome, is still not clear. These preliminary findings merit an extended study to examine more closely the relationship of aflatoxins and kwashiorkor in Zambian children.
AFlatoxin residues in edible tissue of poultry in Zambia
(2011-04-05) Nalube, Sidney Muntanga
The aflatoxins, toxins produced by the fungus Aspergillus flavus, have been detected in both imported as well as locally grown maize in Zambia.The problem of toxicity caused by the ingestion of aflatoxin-contaminated maize was approached by determining the levels of residues in edible tissue of poultry from known dietary levels of aflatoxin in maize. The livers and spleens, gizzards and hearts, and thighs were chosen for aflatoxin residue analysis. This study was conducted to determine the aflatoxin residue levels in tissues of village chickens that had been fed diets containing total aflatoxin concentration of 4750mg/kg of feed (equivalent to aflatoxin Bl concentration of 1650 mg/kg) at 0% (for controls) 25% (for low AF diet) and 75% (for high AF diets) inclusion levels for 21 days. Residues of aflatoxin were determined by thin layer chromatography. Results show that aflatoxins Bl, B2,Gl, G2 and Ml were deposited in all tissues analysed. The highest levels were present in the livers and spleens (8.0 mg/kg, low AF diet; 15.4 mg/kg, high AF diet) and the lowest were in the thighs (1.6 mg/kg, low AF diet; 9.4 mg/kg,high AF diet) . At the end of the experiment, the livers were observed to be pale, enlarged and friable.Since only a small fraction (less than 1%) of the highest level of aflatoxin tested and ingested was deposited in the tissues, either as the original compound or as its metabolite, there appears to be little danger of carry-over of dietary aflatoxin to poultry tissue. The toxic levels (i.e. levels that can cause death) to humans is considered to be approximately 1.7 mg/kg daily (Campbell and Stoloff, 1974), which means that the amount the poultry would need to consume to reach this tissue level would cause pathological symptoms or even death. Therefore the chance of these contaminated birds entering the food chain can be considered to be minimal since people traditionally do not eat poultry dying of unknown cause.
Agricultural transformation in zambia’s Chibombo, Kapiri Mposhi and Mumbwa districts, during the periods 1980-1990 and 1997-2008
(University of Zambia, 2019) Malambo, Augrey Hicigaali
The governance philosophies of the UNIP and MMD governments were very different. These were expected to drastically influence economic performance and livelihoods. The study was undertaken to compare how agricultural crop production among smallholder farmers changed in time and space. The main objective of this study was to establish the patterns of smallholder crop farming and agricultural transformation of Chibombo, Kapiri Mposhi and Mumbwa districts in Central Province of Zambia between the1980-1990 and 1997-2008 periods. An institutional theoretical framework and a household conceptual approach were used to guide the conduct of this study at the institutional and household levels. The neoliberal theory framework of the 1990s was the basis of the emergence of post-1997 agricultural institutions while the dependency theory of the 1980s guided the agricultural institutions of the 1980s. The Institutional theory guided analysis of institutional changes while the Household Economic Approach was used to analyze effects of policies on families. The establishment of changes which had taken place in smallholder crop farming after 1997 and emerging transformations justified the study. Secondary data was obtained through an extensive review of literature. Primary data was obtained through questionnaires distributed to various agricultural officers and 1,367 smallholder farmers in 226 cooperatives. Other pieces of primary data were obtained through Group and personal interviews and observations. Maps were used in the comparison of agricultural patterns existing between 1980-1990 and 1997-2008 periods. Data was analyzed using quantitative and qualitative methods. The study established that the main crops grown during the 1980-1990 period included maize, cotton and groundnuts. After 1997 only maize and cotton continued to dominate while solanum macrocarpon (impwa), sweet potatoes and other crops emerged. The mono cropping system of the 1980s gave way to multicropping, crop rotation and conservation farming practices. Furthermore, after 1997 maize and cotton production remained relatively stable while production of other crops not prominent during the 1980-1990 period increased. Agricultural support institutions of the 1980s collapsed and their places were taken by new privately owned and more sustainable but less spatially distributed institutions. The quality of transport infrastructure deteriorated while two short roads were tarred in Chibombo District. Liberalization became more entrenched especially around market centres and in easily accessible areas of the study districts. In parts of farming areas where government improved and/or up-scaled its policy implementation, sustainable, rewarding and growing agricultural development emerged while in areas where policies were not well implemented or were not followed or not followed correctly, only marginal and declining agricultural development occurred. It is concluded that maize and cotton were widely grown in both study periods; Sunflower production declined after 1997 while new crops such as solanum macrocarpon became common after 1997. The government supported agricultural institutions of the 1980-1990 period collapsed at the end of the 1980s and, new privately and more sustainable institutions emerged. The state of road infrastructure declined after 1997 while positive agricultural transformations characteristic of liberalization emerged near accessible farming areas and market centres. The study concluded that after 1997 changes occurred in cropping systems, the type of crops they grew and crop production; agricultural support institutions; transport infrastructure and new transformations emerged. Key Words: Agricultural Liberalization, Agricultural Support Institutions, Agricultural Transformation, Farmer Response, Smallholder Crop Farming, Transport Infrastructure.
Agro Informatics System
(2015-10-05) Velemu, Charles
Agriculture can be defined as the science or practice of farming, including the growing of crops and the rearing of animals.Agriculture is one of the most important sectors in Zambia's economy and could benefittremendously with the application of information communication technology. Due to tremendous advances during the last decade, information technology is today affecting all the spheres of human life. We can exploit these advances to design a cost-effective system to provide expert advice to farmers and the general public.This project focuses on how information communication technology can be used to better improveagriculture in Zambia.This will be done by implementing an online electronic Agro trading system, a livestock andvegetable farming information repository, a google maps implementation showing cropdistribution in different farming areas of Zambia and an electronic records management system forlocal cooperatives and associations.
An assessment of the Lusaka decongestion project (LDP): a case study of great east road.
(The University of Zambia, 2024) Ng’andu, Lushomo
Traffic congestion is becoming a common occurrence in many major urban centres in Sub Saharan Africa as the numbers and users of motor vehicles increase. This results in a range of undesirable consequences. The purpose of the study was to investigate the decongestion of traffic on the Great East Road after completion of the Lusaka Decongestion Project. The study had four main objectives as follows: To assess the effectiveness of the Lusaka Decongestion Project in reducing traffic congestion along the Great East Road; to investigate the major causes of traffic congestion on Great East Road; to ascertain major points of traffic congestion on Great East Road; and to examine the perception of affected stakeholders on Great East Road after the Lusaka Decongestion Project. The study employed a case study design. It employed a mixed method approach, questionnaires and interview guides were used to collect quantitative and qualitative data. The respondents comprised of key informants from 4 government institutions namely; Ministry of Local Government and rural development, Lusaka City Council, Zambia police Traffic division, and Road transport and safety Agency; 22 public bus drivers; 30 passengers; and 8 private motorists. Observations were made by the researcher on the ground and car counts were done using a video recording device. The study found that indeed the Lusaka Decongestion Project has been effective in bringing about traffic congestion reduction, as it has been shown through the reduction of the queue length of traffic especially during peak hours. It further revealed that the leading cause of the continued traffic congestion is the increase of vehicles on the road. The major points of traffic congestion on Great East Road were Munali Flyover Bridge, up to NRDC bus stop mainly during peak hour. The study recommends that the government should construct road infrastructure to cater for the increase of vehicles, and the other roads should also be expanded and more alternative roads be constructed from where the LDP ended as these were the mostly congested areas. Lastly the city should also create a big bus station at NRDC so that mini-buses do not park on the main road and cause congestion. KEY WORDS: Decongestion, Congestion, Lusaka Decongestion Project, Traffic Congestion and Redesigning
An evaluation of the effectiveness of the environmental impact assessment (EIA) process in zambia : a case of the Chilanga cement plant.
(The University of Zambia, 2024) Mwelwa, Patricia
The study sought to evaluate the effectiveness of Environmental Impact Assessment (EIA) in Zambia using the Chilanga plant as a case study. The objectives of the study were to evaluate the quality of the EIA process conducted at Chilanga plant against international EIA standards; assess the extent to which environmental mitigation measures identified in the EIA report for Chilanga plant have contributed to the reduction of environmental problems emanating from the plant; and to examine the extent to the affected public participated in the EIA process of the Chilanga Cement plant. The research embraced qualitative methods because it provided a deep understanding of the responses, moreover, this allowed for triangulation of results (Creswell, 2007). Within this framework an embedded research design was adopted in which the researcher collected and analysed both types of data at the same time. The qualitative data was embedded in the quantitative data in the interpretation of the overall results. The study used the Lee and Colley review package to analyse the effectiveness of EIA at Chilanga Cement plant throughout the entire cycle of the process focusing on the prediction and mitigation of impacts, public participation, monitoring and follow-up, and to assess the strengths and weaknesses of EIA in Zambia based on feedback from a variety of stakeholders involved in the process and to identify gaps and or factors which limit effectiveness. This was achieved through a critical review of existing literature and policy documents, from which the study drew concepts and ideas that informed the proposed study. The key finding of the study showed that EIA is a well-established environmental management tool in Zambia. Nonetheless, the findings also indicate that there were inadequacies in the implementation process within the environmental sector. The inadequacies were particularly in areas relating description of the development, identification, evaluation and mitigation of key impacts, consideration of alternatives, and consultation and participation of the public.
An evaluation of tourism sector participation in the Livingstone city integrated development plan 2005- 2010, Zambia.
(The University of Zambia, 2022) Zulu, Maxwell
Integrated development planning is a process that requires the involvement of stakeholders in determining the strategic development priorities to their development needs. Stakeholder participation is an instrument used meeting citizen’s development needs when they influence and share control over their development. Besides, stakeholder participation provides opportunities for stakeholders to have access to decision-making processes that inform and shape the formulation and implementation of integrated development plans (IDPs). Stakeholder participation is one of the fundamental principles in the formulation and implementation of IDPs.The first City of Livingstone IDP was a five-year plan targeted for implementation between 2005 and 2010. The plan’s strategic focus was tourism development and stakeholder participation from the tourism sector was key in the development of the IDP because of the tourism focus of the IDP. Their engagement was perceived to be cardinal in shaping the Livingstone City IDP and its implementation, which in the long run, influence the promotion of tourism in the City of Livingstone.This study aimed at assessing the extent to which stakeholders in the tourism sector in the City of Livingstone influenced the formulation and implementation of the Livingstone City IDP. The study utilised a case study method which focused more on qualitative data generated from interviews and observations. The sampling approach of the respondent was purposive sampling, and 27 respondents were interviewed. The collected data were analysed qualitatively using themes that emerged from the responses in the field research.The findings revealed that the key stakeholders in the tourism industry in the study area did not adequately participate in the formulation of the Livingstone IDP. The stakeholder participation mechanisms used did not yield meaningful stakeholder engagement. It led to stakeholders in the tourism sector not being influential during the formulation and implementation of the plan.The study concluded that most of the key stakeholders did not participate in the formulation of the first Livingstone IDP (2005-2010) primarily focused on tourism development and hence, its inability to be effectively implemented. This conclusion demonstrates that stakeholder participation is very critical in the entire process of formulation and implementation of the IDPs in Zambia.
An analysis of public perceptions of domestic solid waste management: The case of the make Zambia clean and healthy programme in Livingstone
(2015-04-13) Chilinga, Givers
Solid Waste Management (SWM) continues to be a major concern in Zambia. As such, the Government of the Republic of Zambia (GRZ), through the Ministry of Local Government and Housing (MLGH) in 2004 instituted the Make Zambia Clean and Healthy (MZCH) campaign aimed, in part, at enhancing solid waste collection and disposal to designated dumpsites countrywide. Therefore, a survey on public perceptions of Domestic Solid Waste Management (DSWM) was, between the March and April, 2013, conducted to evaluate the effectiveness of the MZCH campaign in the city of Livingstone. Three representative localities of the city, presumably of different socioeconomic status (with low, medium and high density households), were selected and surveyed. Although the study was largely quantitative, an eclectic approach was used to collect and analyse field data. A total of 202 respondents were successfully sampled through combined simple random and systematic methods. Coded data from the 202 respondents were entered into the SPSS version 16.0 to generate descriptive statistics, and application of Multivariate Analysis of Variance (MANOVA). MANOVA results show that only two independent variables (monthly income and residence classification) reached statistical significant multivariate differences at p ≤ 0.05. For the monthly income variable, F (6, 376) = 3.55, p=0.002; Wilks’ Lambda (λ) = 0.89; partial eta squared = 0.054; and residence classification, F (6,392) = 2.09, p=0.05; Wilks’ Lambda (λ) = 0.94; partial eta squared = 0.031. This MANOVA result indicates firstly that the demographic factors do not influence public perceptions of the effectiveness of the DSWM system under the MZCH programme. Secondly, there were no major differences in public perceptions of the DSWM system among the different socioeconomic households of the city of Livingstone. Further, the results of this study suggest that the campaign was generally viewed as being ineffective, as local community members largely felt they did not participate in the decision making and implementation of the programme. Overall, the findings of this study suggest that the goals of the campaign were not in tandem with the local community’s preferred DSWM strategies. There is a need, therefore, to involve local community members in identifying future waste management solutions and to provide information to all concerned persons about practical aspects of waste management.

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