Faculty of Science

Permanent URI for this community

http://localhost:4000/handle/20.500.14270/6

Browse

Now showing 1 - 20 of 60

1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its derivatives in marketed Clarius werneri caught from Uganda’s major urban wetlands
(Journal of Toxicology and Environmental Health Sciences, 2014-07-29) Nnamuyomba, Proscovia; Jolocam Mbabazi; Muhammad Ntale
The presence of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and derivatives in the Clarius werneri of Uganda’s major urban wetland ecosystems was investigated. Solid dispersion extraction method for extraction, florisil column method for clean-up, gas chromatograph equipped with an electron capture detector (GC-ECD) for analysis and gas chromatograph equipped with mass spectrophotometer (GC-MS) for confirmation of results were used in this study. The major DDT contaminants detected in the samples were p,p’-DDD, p,p’-DDE and p,p’-DDT which were found in 25, 22 and 21% of the samples, respectively. o,p’-DDD was detected in 19% and o,p’-DDT in 13% of the samples. For o,p’-DDE there were no measurable values since the levels were below limit of quantitation (LOQ). The concentrations of DDT derivatives ranged between ND-0.478 µg/kg for p,p’-DDE, ND-0.387 µg/kg for o,p’-DDD, ND-0.476 µg/kg for p,p’-DDD, ND-0.345 µg/kg o,p’-DDT and ND-0.556 µg/kg for p,p’- DDT. The concentration of total DDT in C. werneri was in the range of 1.111 to 1.328 µg/kg dry wt. Generally, all the samples had DDT derivative levels below the maximum residue limit recommended by Food and Agriculture Organisation/World Health Organization (FAO/WHO) Codex Alimentarius Commission.
Adoption of Mobile Banking Among Agri-Entrepreneurs in Northern Uganda: Do Socioeconomic Factors Matter?
(Food and Humanity, 2025-09-24) Jackson Abandu; Benedict Oyo; Geoffrey Maxwell Malinga; Basil Mugonola
Digital financial technologies drive agricultural value chains and food stability in developing regions. Mobile banking in particular, plays an important role in enhancing financial inclusion, improving the livelihoods and food security of rural farming communities. However, the adoption of this technology by agri-entrepreneurs in Uganda is low and under-explored. This study explored the socioeconomic factors driving mobile banking adoption among agri-entrepreneurs in northern Uganda. Utilizing the Technology Acceptance Model (TAM) as a theoretical framework and a cross-sectional survey design, data were collected through structured questionnaires administered to a representative sample of 480 agri-entrepreneurs. PROCESS macro regression analysis shows that gender, age, education level, marital status, income level, mobile device category and ownership were the primary factors driving the behaviors of mobile banking adoption either directly or indirectly via perceived ease of use and usefulness, which are core variables in the TAM framework. The findings suggest that policymakers, financial institutions, and development agencies should tailor mobile banking interventions to the diverse socioeconomic profiles of agri-entrepreneurs. Targeted strategies such as gender-inclusive programs, digital skills training, and age-specific education are essential to enhance perceived ease of use and usefulness. Investments in rural digital infrastructure and affordable mobile technologies are critical to reducing access barriers. By effectively communicating the practical benefits of mobile banking, stakeholders can accelerate adoption, promote financial inclusion, and support broader goals of rural economic empowerment, food security, and poverty reduction in northern Uganda.
Analysis of the Application of the Discovery Learning Model to Students' Creative Thinking Ability in Reaction Rate Material
(Indonesian Journal of Education Research (IJoER), 2023-08-28) Niski Nadila1, 2,; Louis-Charl Cloete Coetzee; Beatrice Arwenyo
Purpose of the study: The purpose of this study was to describe and determine the relationship between the implementation of the discovery learning model in the matter of the rate of reaction with the students' creative thinking abilities. Methodology: This research is a type of correlational descriptive research. The sampling technique used in this study is Simple Random Sampling. The instrument used in this research is the observation sheet. Data analysis techniques using normality and homogeneity tests. Main Findings: The results of this research are that the application of the Discovery Learning model to reaction rate material can be carried out very well. This is because the teacher corrects errors in applying the model at the next meeting and there is a relationship between the application of the Discovery Learning model and students' creative thinking abilities in the reaction rate material in class XI in the medium category. Novelty/Originality of this study: Provide information about the implementation of discovery learning learning models and their correlation with students' creative thinking abilities.
Application of biochar for the removal of actinides and lanthanides from aqueous solutions.
(Elsevier Inc., 2022) Bursztyn, Amalia L. Fuentesa; Arwenyo, Beatrice; Nanney, Andie L.M.; Ramirez, Arissa; Jamison, Hailey; Venson, Beverly; Mohan, Dinesh; Mlsna, Todd E.; Navarathna, Chanaka
Actinides and lanthanides are elements with unfilled f orbitals and are collectively labeled as the inner transition elements (ITEs). The actinide series includes 15 radioactive metallic ele ments with atomic numbers 89–103 (Cooper, 2000). The actinide elements are classified as light (Ac, Th, Pa, U, Np, Pu, Am) or heavy (Cm, Bk, Cf, Es, Fm, Md, No, Lr) based on their atomic numbers. The actinides fill their 5f sublevels progressively and exhibit char acteristics of both the d-block and the f-block elements. Elements of the actinide series can have oxidation states from +2 to plus +7. In addition to being radioactive, all actinides are paramagnetic and pyrophoric. Except for actinium with one oxidation state of +3, the other actinides are known to show variable oxidation states and more than one crystalline phase. To date, only the first four elements in the actinide series have been found to occur naturally.
Assessing Users Involvement in Analysis and Design Tasks of Electronic Health Information Systems: Experiences, Challenges, and Suggestions to Optimise Involvement
(HELINA and JHIA, 2019) K. Akello, Christine; F. Bbosa, Francis; Nabukenya, Josephine
User requirements play a vital role in the development of usable EHIS. For developers to design better quality, relevant and safer EHIS that meet user needs, they are required to actively engage stakeholders especially in the analysis and design tasks of its development life cycle. This is because they provide context appropriate solutions based on their needs. However, in most cases developers ignore health stakeholders’ input especially during these tasks due to varying perspectives and expectations, complexity, high cost, and variability in time to complete the tasks. This has resulted into various challenges including difficulty in capturing and interpreting user requirements in an effective and efficient manner, poorly designed and unusable systems, unsatisfied user needs, and high maintenance costs. This study thus aimed at assessing users’ involvement in the analysis and design tasks when developing EHIS with a view to understand their experiences, challenges, and suggestions to optimise their involvement. Methods: We employed a cross-sectional survey to investigate and describe the level of user involvement and challenges faced in the analysis and design tasks of the EHIS development process. A total of 36 health practitioners from 13 Key health institutions located in Uganda were selected as respondents. Results: The study revealed that majority of the respondents was involved in EHIS development, with a few involved at analysis and design tasks. Increased costs associated with data collection, followed by lack of consensus in clarifying, articulating and defining user requirements were recorded as the biggest challenges faced by users at requirements gathering, analysis and system design tasks. Regards suggestions to optimising users’ involvement in EHIS development tasks, the study reported that users were very much interested in being involved at all tasks of EHIS development, and consultation of users was paramount in order to incorporate all their needs in EHIS. Conclusions: The results from the study demonstrate the value of user involvement at the analysis and design tasks of EHIS development cycle. User involvement offers benefits in form of reduction in costs, improved productivity due to users easily arriving at a common consensus and positive growth in user attitudes. The researchers intend to incorporate suggestions that emerged from this study to conduct long-term evaluations of existing EHIS and investigate how users’ involvement changes over time.
Bacterial Diversity and their Association with Anchocerca Volvulus Infection in Simulium Flies in Northern Uganda
(Unpublish Dissertation_Gulu University, 2024) Lakot, Amerida
ABSTRACT Onchocerciasis, also known as river blindness, is a chronic and debilitating neglected tropical disease resulting from recurrent infections with the parasitic filarial worm Onchocerca volvulus. This disease is transmitted by blackflies (Simulium species) and poses significant health challenges to affected populations. To date, vector control of blackflies has largely relied on chemical insecticides, an approach that has several drawbacks. There is a pressing need for alternative biological strategies for vector control, one potential approach being the use of 'probiotic' bacteria to modify the physiology of the vector's gut, thereby creating an environment that is hostile to pathogens. This study aimed to survey the bacterial communities in the guts of blackflies from onchocerciasis foci in northern Uganda to identify species with the potential to interrupt onchocerciasis transmission. Simulium flies (n=534) were collected from five sites in Nwoya, Pader, Amuru and Moyo districts in Northern Uganda. The flies were extracted using the SDS method and tests for O. volvulus infection were done using nested PCR. Twenty-five infected flies and forty-seven non-infected Simulium flies were then run for 16s metagenomic PCR using the 16S Barcoding Kit. The library was then subjected to nanopore sequencing. The sequencing identified 12 bacterial phyla with Proteobacteria as the predominant with a relative abundance of 89.7%. The most abundant genera were Enterobacter with 21.4% out of the 149 bacterial genera identified. The bacterial diversity across the sampled districts were significantly different basing on the Shannon index (p=0.26). Eight bacterial genera were significantly associated with flies infected with O. volvulus: Peptoniphilus (p=0.009), Vogesella (p=0.029), Aquabacterium (p=0.018), Curvibacter (P=0.034), Paucibacter (P=0.004), Massilia (P=0.011), Mannheimia (p=0.011) and Shimwellia (P=0.036). On the other hand, six bacterial genera were identified to be predominantly associated with uninfected status. These included Enterococcus (p= 0.03), Citrobacter (p=0.043), Haemophilus (p=0.037), Shewanella (p=0.035), Halotalea (p=0.020) and Zymobacter (p=0.018). The study identified eight novel bacterial genera linked to O. volvulus infection and six associated with non-infection in Simulium flies. Antibacterial drugs could be developed to target the infection-associated genera, while symbiotic bacteria in non-infected flies could be modified to produce molecules against O. volvulus. Further research is needed to understand the physiological mechanisms of these bacteria, which could lead to effective biocontrol strategies.
Budgetary Controls and financial performance of Manufacturing Companies in Uganda: A case study of Soroti Fruit Limited
(Gulu University, 2024-12-22) DANIEL IKOBA
Budgetary control plays crucial role in improving performance of an enterprise. This study investigated the effect of budgetary control on financial performance of manufacturing companies; the case of Soroti Fruits Limited. The objectives of the study were: to examine the budgetary control practices; to assess the level of financial performance; to examine the effect of budgetary controls on financial performance and to determine the moderating effect of business culture on the relationship between budgetary control and financial performance. The study used cross-sectional research design with a quantitative approach. Data was collected from 103 respondents using questionnaire and analysis was conducted using descriptive and inferential statistics with the help of SPSS Version 25.0. Study result revealed a moderate level of implementation of all the elements of budgetary control measures and average level of financial performance. The study revealed a strong significant relationship between all the dimensions of budgetary control and financial performance; cost allocation and variance analysis significantly affect financial performance. Finally, business culture has a significant moderation effect on the relationship between budgetary control and financial performance. The study concluded that: Cost allocation and variance analysis play pivotal roles in influencing Soroti Fruits Limited’s financial performance; and that business culture influences the role that budgetary control play in enhancing the financial performance. The study recommended that: measures to improve financial performance should focus cost allocation and variance analysis; Soroti Fruits Limited should cultivate a supportive and adaptive organizational culture that aligns with its budgetary control practices.
Calibration of Various Detectors for Commissioning of Total Body Irradiation for a New Installation in Maggiore Hospital, Trieste-Italy
(FAMPO : Federation of African Medical Physics organizations, 2023-07-30) Festo Kiragga 1, Rosella Vidimari 2
Calibration of detectors: Gafchromic EBT3(GAF) and Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) was done under reference conditions for use in Total Body Irradiation (TBI) conditions. Three Source Axis Distances (SAD) were chosen: 5m, 4.5 m, and 4m with minimal or no backscatter from the wall. Lateral-Lateral (LL), gantry angle 90o, collimator angle 0o, and 6 MV energy were chosen with respect to the nature of the bunker. Percentage Depth Doses (PDDs) were evaluated, first with a big water phantom using calibrated dosimetry diode, P and then also with RW3 slab phantom (30 x 30 x 30 cm3) at the three positions using GAF. Afterwards, the PDDs were then compared allowing the beam to be characterized in different setups. MOSFETs calibration factors corresponding to each channel were also obtained by first measuring the average dose with a Farmer chamber under reference conditions in the same position. Then the MOSFETs were cross-calibrated against the Farmer chamber. A length of 140 cm (pediatric) was found to be in the flatness region with a dose variation of 3%. GAF, and MOSFETs were calibrated and a calibration curve was plotted for GAF while a table of calibration factors was made for the MOSFETs to be used in TBI conditions. A dose variation of less than 2% was achieved between the Farmer chamber and GAF readings at similar points in the RW3 phantom. The beam characteristics were important parameters to understand the behavior of the beam in non-reference conditions (TBI conditions). These were within the tolerance range as dose variations of up to ± 10% are allowed in TBI conditions. The doses measured with the calibrated Farmer chamber and GAF were compared with less than 2% difference and this meant that the GAF can be used in any TBI setup. Therefore, the bunker was found fit for carrying out the TBI technique, particularly for pediatrics.
Calibration of Various Detectors for Commissioning of Total Body Irradiation for a New Installation in Maggiore Hospital, Trieste-Italy
(African Journal of Medical Physics, 2023-07-30) Kiragga , Festo; Vidimari , Rosella
Calibration of detectors: Gafchromic EBT3(GAF) and Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) was done under reference conditions for use in Total Body Irradiation (TBI) conditions. Three Source Axis Distances (SAD) were chosen: 5m, 4.5 m, and 4m with minimal or no backscatter from the wall. Lateral-Lateral (LL), gantry angle 90o, collimator angle 0o, and 6 MV energy were chosen with respect to the nature of the bunker. Percentage Depth Doses (PDDs) were evaluated, first with a big water phantom using calibrated dosimetry diode, P and then also with RW3 slab phantom (30 x 30 x 30 cm3) at the three positions using GAF. Afterwards, the PDDs were then compared allowing the beam to be characterized in different setups. MOSFETs calibration factors corresponding to each channel were also obtained by first measuring the average dose with a Farmer chamber under reference conditions in the same position. Then the MOSFETs were cross-calibrated against the Farmer chamber. A length of 140 cm (pediatric) was found to be in the flatness region with a dose variation of 3%. GAF, and MOSFETs were calibrated and a calibration curve was plotted for GAF while a table of calibration factors was made for the MOSFETs to be used in TBI conditions. A dose variation of less than 2% was achieved between the Farmer chamber and GAF readings at similar points in the RW3 phantom. The beam characteristics were important parameters to understand the behavior of the beam in non-reference conditions (TBI conditions). These were within the tolerance range as dose variations of up to ± 10% are allowed in TBI conditions. The doses measured with the calibrated Farmer chamber and GAF were compared with less than 2% difference and this meant that the GAF can be used in any TBI setup. Therefore, the bunker was found fit for carrying out the TBI technique, particularly for pediatrics.
Comparison of Acid- and Base-Modified Biochar Derived from Douglas Fir for Removal of Copper (II) from Wastewater
(SEPERATIONS:MDPI, 2024-03-01) Beatrice Arwenyo ,; Prashan M. Rodrig; Olalekan A. Olabode; Hashani P. Abeysingh; Jessie N. Tisdal; Rose C. Azuba; Todd E. Mlsna
Copper is a non-biodegradable heavy metal, and high levels in water bodies cause serious environmental and health issues. Douglas fir biochar has a higher number of carboxylic, phenolic, and lactonic groups, which provide suitable active sites for copper removal. Douglas fir biochar (BC) was modified using 20% solutions of KOH (KOH/BC), H2SO4, (H2SO4/BC), and Na2CO3 (Na2CO3/BC). All materials were characterized using SEM, SEM-EDS, FTIR, TGA, XRD, BET, and elemental analysis. These modifications were done to compare the activations of those sites by measuring copper removal efficiencies. KOH/BC, H2SO4/BC, and Na2CO3/BC materials gave surface areas of 389.3, 326.7, and 367.9 m2 g−1, respectively, compared with pristine biochar with a surface area of 578.9 m2 g−1. The maximum Langmuir adsorption capacities for Na2CO3/BC, KOH/BC, BC, and H2SO4/BC were 24.79, 18.31, 17.38, and 9.17 mg g−1, respectively. All three modifications gave faster kinetics at 2 mg/L initial copper concentrations (pH 5) compared with pristine BC. The copper removal efficiency was demonstrated in four different spiked real water matrices. The copper removals of all four water matrices were above 90% at 2 mg/L initial concentration with a 2 g/L biochar dosage. The competitive effects of Pb2+, Zn2+, Cd2+, and Mg2+ were studied at equimolar concentrations of Cu2+ and competitive ions for all four materials.
Contribution of modified P-enriched biochar on pH buffering capacity of acidic soil
(Elsevier Journal of Environmental Management, 2022-11-06) Arwenyo, Beatrice; Varco, Jac J.; Dygert, Andrew; Brown, Sydney; Pittman, Charles U.; Mlsna, Todd
Biochar can directly hold cations in soil because of the negative charge that exists on its surfaces. Besides, improving soil cation exchange capacity, the negative charges on biochar surfaces can buffer acid soil by pro tonation and deprotonation mechanisms. Moreover, biochar ameliorates soil acidity due to the presence of ox ides, carbonates, and hydroxides of its basic cations (Ca, Na, K, and Mg). Both biochar surface functional group and basic cation concentrations can be altered by modification with chemical agents which can affect its soil pH buffering capacity. However, the impact of modified biochar application on soil pH buffering capacity is still scanty. This study investigated the pH buffering capacity of acidic soil amended with three P-enriched modified Douglas fir biochars and compared this buffering capacity to amendment with untreated Douglas fir biochar. These three P-enriched biochars, were prepared by treating Douglas fir biochar (DFB), respectively, with: 1) anhydrous calcium chloride (CaCl2) and potassium phosphate monobasic (KH2PO4), 2) calcium carbonate (CaCO3) and diammonium phosphate {(NH4)2HPO4} and 3) an aqueous solution of magnesium sulfate (MgSO4), potassium hydroxide (KOH) and potassium phosphate monobasic (KH2PO4). The three P-enriched biochars were designated as CCPP, CAPP and MSPP, respectively. The soil pH buffering abilities were largely dependent on the added biochar’s alkalinity and ash contents. The residual soil CEC was highly correlated (r ≥ 0.9), with the soil buffering capacity. Both alkalinity and pH buffering capacity improved following the order CCAP > CCPP > MSPP > DFB, while residual soil CEC followed the order CAPP > MSPP > CCPP > DFB. The pH buffering ca pacity of the soil after amendments with 10% CAPP, CCPP MSPP and BFB rose by 84.8, 58.3, 3.0 and 2.5%, respectively. Whereas MSPP had higher concentrations of K+ and Mg2+, greater concentrations of Ca2+ were present in CCAP and CCPP than MSPP. So, Ca2+ concentrations in biochar exerts a greater influence on alkalinity and buffering capacity than Mg2+ and K+ because of 1) its smaller effective hydration radius and larger charge density. 2) calcium hydroxide has a greater water solubility than magnesium hydroxide providing more available base. Since pH buffering capacity depends on cation exchange sites, soil additives containing Ca2+ are prone to create greater impacts than Mg2+ and K+ additives.
Dichloro-diphenyl-trichloroethane (DDT) residue levels in marketed Silver Fish (Rastreneobola argentea) caught from major water bodies in Uganda
(Academic Journal, 2014-06-25) Nnamuyomba, Proscovia; Mbabazi, Jolocam; Ntale Muhammad
Silver fish (Rastreneobola argentea) samples from Lake Victoria and Lake Kyoga were analyzed for dichloro-diphenyl-trichloroethane (DDT) and metabolites using a Gas Chromatograph equipped with an Electron Capture Detector. Confirmation of results was by Gas Chromatography equipped with Mass Spectrophotometer (GC-MS). DDT and metabolites were detected in 90% of the total samples (63 out of 70). pp’ DDT was the most frequently detected residues in the samples whereas op’ DDE was detected in none of the samples. The mean ΣDDT concentrations in fish from Lake Victoria varied from 0.147 to 0.396 µg/kg while that in Lake Kyoga varied from 0.207 to 0.506 µg/kg dry wt of fish sample. The concentration of total DDT in the fish samples ranged from 0.147 to 0.506 µg/kg dry wt. This was far below the recommended FAO limit of 5000 µg/kg for fish (edible portion), implying that the fish are safe for human consumption.
Dichlorodiphenyltrichloroethane (DDT) and its metabolites in house dust, soil and selected food crops from indoor residual sprayed areas of Apac and Oyam Districts, Uganda
(African Journal of Pure and Applied Chemistry, 2022-06-12) Mukasa paul; Wasswa John; Namuyomba Proscovia; Ntambi Emmanuel
Dichlorodiphenyltrichloroethane (DDT) levels and its metabolites are reported in 75 soil and 75 vegetable samples from the vicinity of homesteads sprayed with DDT during indoor residual spraying (IRS) pilot exercise, carried out in 2008 in Apac and Oyam districts, Uganda as a measure to control malaria. The samples were randomly and conveniently collected in 2020 from selected villages of the districts, extracted using solid dispersion and multi-residue methods for soil and vegetable samples, respectively and analyzed using GC-ECD and GC-MS. DDT residues were detected in all samples collected. The ΣDDT (µg kg-1) in all indoor house dust, outdoor soil samples from villages of Apac and Oyam districts and control areas were 69.9±20.9 and 8.9±4.7, 113.4±22.6 and 15.4±4.3, and 1.13±0.27 and 1.8±0.9, respectively. ΣDDT were significantly higher (p < 0.05) in the study areas than the control areas. In vegetables, ∑DDT (µg kg-1) ranged between 1.7±0.3 and 8.3±4.0 and 2.3±0.4 and 11.4±7.5 in the study and control areas, respectively. Abelmoschus esculentus and Gynandropsis gynandra had the highest levels. The results suggest that IRS had an effect on DDT levels in the environment. However, ∑DDT in vegetables were significantly below (P < 0.05) the EU EMRL, thus, the results raise no concern regarding the potential health effects of DDT to the residents. Nevertheless, due to bioaccumulation effects of DDT, to control malaria, measures like Ecohealth rather than IRS of DDT should be embraced.
Diet acceptance and preference of the edible grasshopper Ruspolia diferens (Orthoptera: Tettigoniidae)
(The Japanese Society of Applied Entomology and Zoology, 2018-02-23) Malinga, Geofrey M.; Valtonen, Anu; Lehtovaara, Vilma J.; Rutaro, Karlmax; Opoke, Robert; Nyeko, Philip; Roininen, Heikki
The edible grasshopper Ruspolia diferens (Orthoptera: Tettigoniidae) gathered seasonally from the wild is a highly valued and an economically important edible insect, particularly in East Africa. To reduce the pressure on wild populations, a sus tainable mass production technique needs to be developed. Unfortunately, however, basic biological know-how on feeding habits of R. diferens is poorly understood, which poses a constraint on the development of mass-rearing technology. Here, we evaluated the acceptance and feeding preference of R. diferens for 16 cultivated or processed foods using no-choice and multiple-choice laboratory bioassays. The results indicated that adult R. diferens can eat a wide variety of foods but does not necessarily accept all the foods equally. Furthermore, our experiments showed that R. diferens has high ability to select diet among those available. The order of decreasing preference was wheat bran > germinated fnger millet > rice seed head > fnger millet seed head > chicken feed egg booster > sorghum seed head. Finally, our study indicated that sex and color morph are not associated with the order of acceptance and preference of diets in R. diferens. These results show potential foods that could be utilized for developing future mass-rearing methods for R. diferens.
EFFECTIVENESS OF THE SHIELDING MECHANISM IN ROOMS HOUSING X-RAY DIAGNOSTIC EQUIPMENTS :A CASE STUDY OF MULAGO HOSPITAL, UGANDA
(International Journal of Innovative Research in Advanced Engineering (IJIRAE), 2018-02-02) Festo Kiragga; Kisolo Akisophel; Nakatudde Rebecca
The effectiveness of the shielding against ionizing radiation in controlled and supervised areas of four (4) selected imaging rooms of Mulago hospital was determined. Scattered radiation transmitted to the operator’s console, leakage through the walls and doors to the patient waiting areas was also determined. The effective doses to occupational workers were also determined. The availability and effectiveness of the lead aprons and other protective gears was also investigated. Thermoluminiscent Dosimeters (TLDs) were installed at selected points for a period of four (4) weeks. Radiation leakages to the members of the public were measured using a survey meter, scattered X-ray radiation to staff was measured using TLD badges. The mean scattered radiation in the imaging rooms varied from 1.19 mSv/month in the Computed Tomography (CT) room to 0.38 mSv/month from the Casualty Center (CC). The effective doses to occupational staff were highest in Room 4 (R4) (plain radiography) of 6.8 mSv/yr and lowest in CC at 1.4 mSv/yr. Radiation leakages through selected doors were found to be 18.1 mSv/hr at the Uganda Cancer Institute (UCI). Though there was some leakage, the available shielding was found to be generally effective.
Effects of environmental temperature on the growth performance of a tropical Oreochromis esculentus (Graham, 1928). Implications for the species conservation
(Willey., 2022-09-14) Nagayi, Kalule Yawe jane; Kisakye Joseph; Tenywa Mwanja Matthew ,; Nattabi. Juliet; Opio Alfonse
Climate variability and change are currently recognised global challenges. However, the impacts of rising temperatures may be greatest on tropical freshwater fish, which already exist in warm environments and may be living close to their critical thermal maximum. However, there is limited species- specific information on tropical species’ adaptive capacity to increased temperature. This study examined various growth attributes in juvenile populations (farmed, L. Kacheera and L. Nabisojjo) of a critically endangered tropical Oreochromis esculentus to determine its adaptive potential. Fish were acclimated at 25, 28, 31 and 34°C for 28 days. Overall, survival rates were high. Growth coefficient b was not significantly different from three (b = 3) in all treatments, implying isometric growth. The specific growth rates (SGRs), body condition K, and hepato- somatic indices (his) declined as the acclimation temperatures increased. Although SGR showed significant variations only among populations, the highest in L. Nabisojjo, K and HSI showed significant variations among treatments. Overall, the growth attributes declined at higher acclimation temperatures, but remained within acceptable ranges, implying that the species may attain normal growth at elevated temperatures experienced in outdoor aquaculture systems, despite its warm environmental background. Hence, we recommend selective breeding for temperature resilience and species introduction into aquaculture using broodstock from L. Nabisojjo.
Effects of thermal acclimation and ecological background on the physiological responses of juvenile Oreochromis esculentus (Graham, 1928). Implications for the species adaptive capacity to global warming
(Aquaculture Research, 2021-10-12) Nagayi, Jane Kalule Yawe; KisakyeJohn , Joseph; Tenywa Mwanja, Matthew; Nattabi; Opio Alfonse
Climate change is a recognized global concern in the 21st century. Water temperature elevation is likely to affect fish physiological and ethological function, causing great economic losses for fisheries resources and aquaculture production. Fish are particularly vulnerable to climate change as they are unable to control their body temperatures with changes in environmental temperature. This study assessed the effects of thermal acclimation in three juvenile populations of Oreochromis esculentus on the critical thermal maximum CTmax, cortisol, biochemical and haematological responses to acute temperature increase (0.3°Cmin−1). Fish from Senya farm, Lake Kacheera and Lake Nabisojjo were acclimated at 25°C, 28°C, 31°C and 34°C for 21 days at Kajjansi aquaculture research and development centre KARDC. The CTmax and blood cell counts increased, while plasma cortisol, glucose and proteins decreased at higher acclimation temperatures. Two-way ANOVA showed significant differences among treatments in CTmax, cortisol, proteins and erythrocytes indices, but not in glucose and leucocytes. However, significant variations among populations were only showed in CTmax. Overall, these results suggest that O. esculentus can respond to higher climate change induced temperatures, when allowed time for acclimation. Since temperature adaptation not only depends on the parameters assessed in this study, we recommend further investigations into metabolic rate and digestive enzymatic activity.
Efficacy of In Ovo Delivered Prebiotics on Growth Performance, Meat Quality and Gut Health of Kuroiler Chickens in the Face of a Natural Coccidiosis Challenge
(MDPI journal of Nutrients, 2019-10-28) Angwech, Harriet; Tavaniello, Siria; Ongwech, Acaye; Kaaya, Archileo N.; and Maiorano, Giuseppe
A study was carried out to assess the efficacy of prebiotic delivered in ovo on performance, carcass traits, meat quality and gut health in the face of a natural coccidiosis infection in Kuroiler chickens. On d 12 of incubation, 150 fertile eggs were divided into a prebiotic group injected with trans-galactooligosaccharides (Bi2 tos) and a control group uninjected. Hatched chicks from each group were further divided: One group received antibiotic chick formula while the other was left untreated, giving rise to 4 groups—Control (C), Antibiotic (A), Bi2 tos (B), and Bi2 tos + Antibiotic (AB). Prebiotic improved growth performance at six weeks of age, AB birds were the heaviest at the end of the rearing period. The highest intestinal lesion scores and oocyst counts were recorded in C birds. B group had a slightly higher carcass weight and cuts yields tended to be higher in treated groups compared to C. Meat from B group displayed a higher amount of polyunsaturated fatty acids compared to C and a positively lower n-6/n-3 ratio compared to C and A. In conclusion, prebiotics with or without antibiotics reduced severity of intestinal lesions and oocyst excretion induced by natural infection with Eimeria, with positive effects on Kuroiler chicken productive traits.
Establishment of Computed Tomography Diagnostic Reference Levels on Paediatric Patients in Uganda
(Journal of Radiation and Nuclear Applications, 2021-08-01) Ayugi. G,; Oruru. B,; Kiragga. F,; Kisembo. H; Kyagulanyi. H
Paediatric dosimetry in radiation protection when compared with adults is based on radiation sensitivity of children to radiation. Children are known to be at a higher risk of developing radiation-induced cancer. The aim of this study was to determine the radiation doses to paediatric patients during computed tomography procedures (CT) so that a diagnostic reference levels (DRLs) could be proposed. DRLs are useful in high dose examinations such as CT to achieve collective dose reduction. Information about patients, protocol and CT system for 684 patients were recorded during 2019 and 2020 from five CT scanners. The dose was determined in four age groups: 0-1 year, 1-5 years, 5-10 years, and 10-15 years for the head, chest and abdomen protocols. The 75th percentile of CTDIvol and DLP were considered as DRLs and compared with IAEC and Japan DRLs. CT dosimetry software Impact CT patient dosimetry calculator, version 1.0.4 with National Radiation Protection Board SR250 data set, was used to validate and compare scanner generated dose values. DRLs are proposed using CTDIvol (mGy) and DLP (mGy cm). The mean DRL of 43.6 and 922 for the head, 3.0 and 258 for the Chest and 3.1 and 292.5 for the abdomen were established during the study. There was high deviation in head CT doses compared to the reported DRLs in IAEC and Japan. The established DRLs for head were higher than those available in other countries. This study showed the need for harmonization of radiation dose optimization of this protocol.
Establishment of Computed Tomography Diagnostic Reference Levels on Paediatric Patients in Uganda
(NSP: Natural Sciences Publishing Cor., 2021-09-01) Ayugi G 1,*, B. Oruru 1, F. Kiragga 2, H. Kisembo 3 and H. Kyagulanyi 1.
Paediatric dosimetry in radiation protection when compared with adults is based on radiation sensitivity of children to radiation. Children are known to be at a higher risk of developing radiation-induced cancer. The aim of this study was to determine the radiation doses to paediatric patients during computed tomography procedures (CT) so that a diagnostic reference levels (DRLs) could be proposed. DRLs are useful in high dose examinations such as CT to achieve collective dose reduction. Information about patients, protocol and CT system for 684 patients were recorded during 2019 and 2020 from five CT scanners. The dose was determined in four age groups: 0-1 year, 1-5 years, 5-10 years, and 10-15 years for the head, chest and abdomen protocols. The 75th percentile of CTDIvol and DLP were considered as DRLs and compared with IAEC and Japan DRLs. CT dosimetry software Impact CT patient dosimetry calculator, version 1.0.4 with National Radiation Protection Board SR250 data set, was used to validate and compare scanner generated dose values. DRLs are proposed using CTDIvol (mGy) and DLP (mGy cm). The mean DRL of 43.6 and 922 for the head, 3.0 and 258 for the Chest and 3.1 and 292.5 for the abdomen were established during the study. There was high deviation in head CT doses compared to the reported DRLs in IAEC and Japan. The established DRLs for head were higher than those available in other countries. This study showed the need for harmonization of radiation dose optimization of this protocol.

Browse

Browsing Faculty of Science by Title

Results Per Page

Sort Options