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3 - Advanced biopolymer-based green composites: their processing and damage mechanism
(ScienceDirect, 2021-09) Mwesigwa, Ronald; Nkomo, Nkosilathi Zinti; Mwasiagi, Josphat Igadwa; Wanyama, Aaron
Composites are constructions of lightweight bearing high toughness and custom-made properties for precise use, globally. In addition, bio-based composites are constructions made from natural and/or synthetic fibers and petroleum-based polymers and/or biodegradable polymers. Furthermore, green composites are constructions obtained from biopolymers and agricultural/natural or biofibers that are more environmentally friendly hence highly sought after worldwide. Currently, green composites are offering enormous benefits that are promoting them in the automotive, packaging, construction, electrical and insulation, furniture, consumer, and household industries among others. This chapter therefore presents advanced biopolymer-based green composites in relation to their processing and damage mechanism. Subtopics covered include processing and characterization of biopolymers, agricultural/natural fibers, and green composites. Various failure and damage mechanisms pertaining to green composites are also covered.
Acid production, growth kinetics and aroma profiles of lactobacillus flora from stilton cheese
(Elsevier: Food Chemistry., 2019-02-23) Mugampoza, Diriisa; Gkatzionis, Konstantinos; Linforth, Robert S.T.; Dodd, Christine E.R.
The effect of Lactobacillus plantarum isolates from Stilton cheese on aroma profiles of milk fermentation was examined. Representative Lb. plantarum isolates were cultured alone and in combination with acid-producing and non-acid producing Lactococcus lactis NCIMB 9918 in UHT milk at 30 & 18 °C for 48 h & 12 weeks, respectively in presence and absence of salt, simulating cheese production and ripening. During long-term ripening, Lb. plantarum grew faster when co-cultured with non-acid producing Lc. lactis in the presence of salt. One isolate of Lb. plantarum produced the highest concentration of alcohols, organic acids and acetoin. Co-culture of Lb. plantarum with acid-producing Lc. lactis enhanced acid and alcohol production, whereas co-inoculation with non-acid producing Lc. lactis increased acetoin synthesis. Lb. plantarum is an incidental organism in cheese and its presence is unpredictable. Occurrence of different genotypes of Lb. plantarum could contribute to batch to batch variation in the cheese aroma characteristics.
Activity levels of gamma ray emitting radionuclides in food crop samples in selected tobacco farming areas in Aura and Maracha districts
(Kyambogo University (unpublished work), 2017-12) Anguani, Epiphany Mike
The farming activities, especially Tobacco production in Terego East and Terego West in Arua district and Maracha East County in Maracha district employ fertilizers such as NPK, DAP, CAN, TSP and UREA to enhance soil fertility property and to increase Tobacco production. Fertilizers are known to contain radionuclides such as uranium, radium, potassium etc., that originate from phosphate rocks; that could accumulate in the soil over the years and these may be absorbed by food crops grown on such soils. Humans who feed on these food crops may then absorb such radionuclides. As Human cells absorb radiation energy, molecules in them get damaged resulting into malfunction of cells through genetic mutation and this can then be a health risk. in this study the specific activity levels of gamma ray emitting radionuclides in selected food crop samples (maize, rice, sorghum, cassava, ground nuts, beans and simsim), grown in soils contaminated by fertilizers was determined using Gamma ray spectroscopy technique, that uses Nal(Tl) detector. The samples were obtained from the six Sub Counties of Omugo, Aii-vu, Odupi, Oriama, Katrini and Bileafe in Arua District and three Sub Counties of Tara, Yivu and Nyadri in Maracha District. The sampling technique used was purposive and simple random. In summary, the mean specific activity levels of radium, thorium, uranium and potassium were 64.0 Bqkg·1 , 6.0Bqkg·1, 3.5 Bqkg·1 and 185.1 Bqkg·1 respectively, in the crop samples considered. The mean specific activity levels for potassium was the highest, followed by radium, thorium ·and the least level shown by uranium. The mean absorbed dose rate was 40.9 nGy/h and the mean annual effective dose rate was 0.1 mSv/yr., for all the crop samples considered. The mean annual effective dose rate for all crop samples determined in this study were within the range recommended by the International Atomic Energy Agency as having no observable effects in the human body. Therefore it is recommended that consumption of the food crops investigated should continue as it poses no potential radiation hazard. It is further recommended that investigation should be performed on other crops which are not investigated in this study.
Advanced biopolymer-based green composites: their processing and damage mechanism
(Sustainable Biopolymer Composites : Woodhead Publishing, 2021-09-17) Mwesigwa, Ronald; Nkomo, Nkosilathi Zinti; Mwasiagi, Josphat Igadwa; Wanyama, Aaron
Composites are constructions of lightweight bearing high toughness and custom-made properties for precise use, globally. In addition, bio-based composites are constructions made from natural and/or synthetic fibers and petroleum-based polymers and/or biodegradable polymers. Furthermore, green composites are constructions obtained from biopolymers and agricultural/natural or biofibers that are more environmentally friendly hence highly sought after worldwide. Currently, green composites are offering enormous benefits that are promoting them in the automotive, packaging, construction, electrical and insulation, furniture, consumer, and household industries among others. This chapter therefore presents advanced biopolymer-based green composites in relation to their processing and damage mechanism. Subtopics covered include processing and characterization of biopolymers, agricultural/natural fibers, and green composites. Various failure and damage mechanisms pertaining to green composites are also covered.
Aflatoxins in Uganda: an encyclopedic review of the etiology, epidemiology, detection, quantification, exposure assessment, reduction, and control
(International Journal of Microbiology, 2020-01-08) Timothy, Omara; Winfred, Nassazi; Tom, Omute; Aburu, Awath; Fortunate, Laker; Raymond, Kalukusu; Bashir, Musau; Brenda, Victoria Nakabuye; Sarah, Kagoya; George, Otim; Eddie, Adupa
Uganda is an agrarian country where farming employs more than 60% of the population. Aflatoxins remain a scourge in the country, unprecedentedly reducing the nutritional and economic value of agricultural foods. This review was sought to synthetize the country’s major findings in relation to the mycotoxins’ etiology, epidemiology, detection, quantification, exposure assessment, control, and reduction in different matrices. Electronic results indicate that aflatoxins in Uganda are produced by Aspergillus flavus and A. parasiticus and have been reported in maize, sorghum, sesame, beans, sunflower, millet, peanuts, and cassava. The causes and proliferation of aflatoxigenic contamination of Ugandan foods have been largely due to poor pre-, peri-, and postharvest activities, poor government legislation, lack of awareness, and low levels of education among farmers, entrepreneurs, and consumers on this plague. Little diet diversity has exacerbated the risk of exposure to aflatoxins in Uganda because most of the staple foods are aflatoxin-prone. On the detection and control, these are still marginal, though some devoted scholars have devised and validated a sensitive portable device for on-site aflatoxin detection in maize and shown that starter cultures used for making some cereal-based beverages have the potential to bind aflatoxins. More efforts should be geared towards awareness creation and vaccination against hepatitis B and hepatitis A to reduce the risk of development of liver cancer among the populace.
Analysis of fitness trends among urban dwellers in Kampala: the case of selected health clubs and fitness studios
(Kyambogo University (un published work), 2004-11) Soita, W. Paschal
Physical fitness is important in its general contribution to one s health. For effectiveness programme delivery has to be handled professionally and ethically to meet specific minimum standards. These include safety state-of-the-art equipment and trained practitioners. When well harnessed, some of societal health problems traditionally associated with hypokinetic conditions and sedentary work practices may be prevented, reduced or even eliminated. This study therefore assessed the extent to which personnel facilities and programmes within health clubs in Kampala City meet the minimum professional standards as required. To elicit the data a number of research tools were employed, including Questionnaires, Observation and Interviews with consumers and providers of products and services. A random sample of 144 (23% of the target population) subjects was selected from 12 purposively selected health clubs out of 35 considered for the study. The data collected \ as mainly subjected to qualitative treatment although at some point Chi-square, x 2,was used to establish if there existed correlation between age and gender with participation. The major findings of the study included: • Fitness as a fast-growing industry in Kampala but embroild with weaknesses in membership admission, low practitioner education levels and to a large extent obsolete equipment they use.
Analysis of injuries incurred by amateur female rugby players: A case of selected clubs in Kampala district, Uganda
(Kyambogo University[unpublished work], 2013-10) Atukei, Harriet Proscovia
Rugby players are exposed to injuries which are most especially on the upper and lower limbs since the game involves a lot of collisions. The purpose of the study was to analyse the injuries incurred by 25 amateur female rugby players in two selected clubs in Kampala District, Uganda. The objectives of the study were to establish the injuries incurred by female rugby players during rugby playing, to identify the factors that lead to injuries incurred by the female players during the game and to establish relationship between causes and injuries during training and competition. It was hypothesized that: there was no significant relationship between the occurrence of injuries and the time of the day of occurrence; and that there was no significant relationship between the occurrence of injuries and the phase of play; and finally there was no significant relationship between the occurrence of injuries and the site of the body at which the injury occurred. Questionnaires for players, coaches and medical personnel as well as an observation checklist were used to collect data. Finally, an interview guide was used to collect the information that could not be obtained using the other tools. The study was mainly quantitative in which descriptive statistics was used and data__was_analyzed using SPSS. The hypotheses were tested using Chi-square and Pearson's correlation at P < 0.05. Both frequency and cross-tables were used for data presentation. The results indicated that most injuries (92%) were bruises caused by collision with other players and many injuries (56%) were sustained during the middle phase of the games. Participants experienced most injuries around the knee and the treatment given to most injured participants (47%) was pain killers. Occurrence of injuries had no significant relationship to the time of occurrence of the injury, phase within which the injury occurred and the degree of the injury. Based on the findings, the study recommended consideration of time of the day, necessary protective gear and presence of qualified and full time medical personnel during the competitions in addition to sensitization of the teams administration and players about the usefulness of injury prevention in relation to retention and performance of the players. More research should be carried out to find out about injury management and rehabilitation of injured athletes.
Analysis of the 24-h microfilarial periodicity of Mansonella perstans
(Springerlink: Parasitology Research, 2008-12-24) Asio, Santa Maria; Simonsen, Paul E.; Onapa, Ambrose W.
The Mansonella perstans microfilarial (mf) periodicity in peripheral blood was analysed in a group of 32 healthy individuals from an endemic community in Uganda. The majority of individuals had maximum mf intensity during the first and minimum during the last 12 h of the day. Mean mf ratios (i.e. time-specific counts in relation to mean count for the individual) indicated a weak but significant diurnal periodicity with peak intensity around 0800 h. Trigonometric analysis of the ratios, assuming a harmonic wave pattern of periodicity, gave a periodicity index of 11.1 and a peak time of 0645 h. The higher mf intensities in the early morning appeared to coincide with the preferred biting hour of the vectors. The observed weak pattern of mf periodicity indicates that the sampling time of blood specimens for diagnosis will have only minor effect on diagnostic sensitivity.
Analysis of the model on the effect of seasonal factors on malaria transmission dynamics
(Hindawi Journal of Applied Mathematics, 202-08) Yiga, Victor; Nampala, Hasifa; Tumwiine, Julius
Malaria is one of the world’s most prevalent epidemics. Current control and eradication efforts are being frustrated by rapid changes in climatic factors such as temperature and rainfall. This study is aimed at assessing the impact of temperature and rainfall abundance on the intensity of malaria transmission. A human host-mosquito vector deterministic model which incorporates temperature and rainfall dependent parameters is formulated. The model is analysed for steady states and their stability. The basic reproduction number is obtained using the next-generation method. It was established that the mosquito population depends on a threshold value θ, defined as the number of mosquitoes produced by a female Anopheles mosquito throughout its lifetime, which is governed by temperature and rainfall. The conditions for the stability of the equilibrium points are investigated, and it is shown that there exists a unique endemic equilibrium which is locally and globally asymptotically stable whenever the basic reproduction number exceeds unity. Numerical simulations show that both temperature and rainfall affect the transmission dynamics of malaria; however, temperature has more influence.
Anthropometric characterisation of male soccer players in northern Uganda
(Kyambogo University, 2021-08) Opiyo, Washington
The study purpose was to assess anthropometric characterisation of male soccer players in Northern Uganda. One hundred ninety-two players aged between 16 and 36years were sampled taking into account their playing positions as goalkeepers (GK), defenders (DF), midfielders (MF) and forwards (FW). Descriptive cross- sectional design was employed. The ISAK protocol was considered to measure anthropometric variables: weight; height; circumferences; n_/10; skinfolds, n_/2; and breadths, n_/6. BMI n-1, %BF, and somatotype were determined. The data was analyzed by STATA version 14C, Bartlett’s test for hypothesis done and level of significance was set at (p<0.05). The results showed that GK (71.3kg ± 4.5; 177.5 cm ± 6.7) were the heaviest and tallest compared to others and MF (67.2 kg ± 6.6; 171.6 cm ± 5.9) were the lightest and shortest.Majority (82.8%) of the players had normal BMI, with higher mean %BF (16.3%) than the recommended fat percentage(6-13%) and they showed dominancy in mesomorphic somatotype.There was no significant difference (p ≤ 0.05) in; BMI (p=0.30, F=1.22), %BF (p=0.22, F=1.49), endomorph (p=0.20, F=1.57), and ectomorph (p=0.56, F=0.68) with exception of mesomorph (p=0.01, F=3.65) that showed significant difference among players in different playing positions. The study concluded that players in Northern Uganda were generally heavier and taller with most of them having higher body fat percentage than the recommended fat percentage for soccer players. Therefore, this study recommended that coaches should design training that cater for the anthropometric requirements of each playing position to improve soccer performance. Keywords: Anthropometry, body composition, soccer performance.
Antibacterial and anticancer activities of green-synthesized silver nanoparticles using Photinia glabra fruit extract
(Nanomedicine, 2023-08) Tabbisa, Namulinda; Lei-Lei, Bao; Justus, Kwetegyeka; Ivan, Gumula; Yi-Jia, Yan; Zhi-Long, Chen
Aims: We prepared Photinia glabra (PG) aqueous fruit extract, utilized it to synthesize silver nanoparticles (PG-Ag NPs) and evaluated the antibacterial and anticancer activities of the nanoparticles (NPs). Materials & methods: Silver nitrate aqueous solution was reduced to PG-Ag NPs using aqueous PG fruit extract. NP shape, size, composition and functionalization were determined using transmission electron microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared and x-ray diffraction. Results & conclusions: PG-Ag NPs were spherical, approximately 39–77 nm-sized, functionalized surfaces with notable antibacterial activity against both Escherichia coli and Staphylococcus aureus, with an MIC <30 ug/ml and cytotoxicity toward esophageal cancer cells, with IC50 values less than 20 ug/ml. PG-Ag@rt NPs have been shown to be a potent antibacterial and anticancer agent, and their enriched particle surfaces can be conjugated with other compounds for multibiomedical applications.
Antibacterial properties of phytochemicals isolated from leaves of alstonia boonei and aerial parts of ipomoea cairica
(Natural Product Communications, 2024-09-26) Gumula, Ivan; Kyarimpa, Christine; Nanyonga, Sarah Kiwanuka; Kwesiga, George; Busulwa, George; Opio, Boniface; Heydenreich, Mathias; Omara, Timothy
Objective: The leaves of Alstonia boonei and aerial parts of Ipomoea cairica are used for treatment of microbial infections among other ailments in African traditional medicine. The aim of this study was to investigate the antimicrobial phytochemicals in A. boonei leaves and Ipomoea cairica aerial parts to validate their traditional use in Ugandan herbal medicine. Methods: The plant materials were separately extracted using a dichloromethane/methanol (1:1) solvent system and subjected to repeated chromatographic separation to isolate pure compounds. The chemical structures of the isolated compounds were determined through 1H NMR, 13C NMR and 2D NMR(COSY, HSQC and HMBC). The antibacterial activity of the extracts and pure compounds were assessed using the agar well diffusion method. Results: Chromatographic fractionation of the extracts yielded trans-fagaramide and a pentacyclic lupane-type triterpenoid, lupeol, from A. boonei, and friedelin from I. cairica. Trans-fagaramide was identified for the first time in the Alstonia genus while friedelin was identified for the first time in I. cairica. The isolated compounds demonstrated antibacterial activity, with trans-fagaramide showing a minimum inhibitory concentration (MIC) of 125 μg/mL against Pseudomonas aeruginosa and 250 μg/mL against Staphylococcus aureus, Salmonella typhi and Escherichia coli. Friedelin exhibited a MIC of 125 μg/mL against Escherichia coli and 250 μg/mL against Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhi. Conclusion: The antibacterial activities observed in this study support the traditional use of A. boonei and I. cairica by indigenous communities in Uganda for treating microbial infections.
Antimicrobial activity of cotton and silk fabrics dyed with Datura stramonium (Jimson weed) plant leaf extracts
(African Journal of Microbiology Research, 2019-11) Musinguzi, Alex; Mwasiagi, Josphat Igadwa; Wanyama, Aaron; Gumisiriza, Onesmas
Functional finishes are agents that are applied to fabrics to make them suitable for specific uses and contribute a specific attribute to a fabric without altering its appearance. In this context, the present study reveals the importance of dyed fabrics with Datura stramonium plant leaf extracts to control antibiotic-resistant bacteria, which have been a threat to human health and posed noticeable challenges confronted with medical physicians in the treatment of many infectious diseases. More still, the importance of using natural dye is not limited to its antimicrobial and other medicine values but also to its wide range of advantages via elimination of environmental pollution due to the usage of synthetic dyes. 100% plain woven, desized, scoured and bleached cotton fabric samples and 100% degummed and bleached hand knitted silk fabric samples were dyed with aqueous extracts from D. stramonium plant leaves in combination with Alum and Iron Sulphate as mordants using post-mordanting method and then tested against two strains of Staphylococus aureus (Gram-positive bacteria) and Pseudomonas aeruginosa (Gram-negative bacteria) using Agar diffusion method as per SN195920-1992 standard. The fastness properties (wash fastness, light fastness and rubbing fastness) of the dyed fabrics were assessed following guidelines from The American Association of Textile Chemists and Colorists (AATCC) and International Organization for Standardisation (ISO) testing methods. Spectrophotometric experiments were employed to evaluate the colour strength (K/S) of the dyed samples. The antimicrobial activity results showed that for both cotton and silk dyed fabric samples; there was an interruption of the microbial growth beneath the fabric and a clear zone of inhibition around the fabric. Dye ability and fastness results showed that dyed fabric samples with D. stramonium extracts using mordants had relatively high colour strength (K/S) values as compared to the control fabrics which were dyed without a mordant and their colorant was more stable to light, rubbing and washing, respectively.
Antimicrobial, Growth, Acid and Aroma Properties of the Dominant Microflora Isolated at Different Stages of Gouda Cheese Production
(Kyambogo University [unpublished work], 2023-10) Namiiro, Josephine
The microflora of Gouda cheese is dominated by starter culture lactic acid bacteria (SLAB) and non-starter organisms, which are not deliberately added. Both of these groups of microorganisms are responsible for development of the cheese flavor and organoleptic properties during ripening. This study generally aimed to characterize the dominant microbial species at different stages of Gouda cheese production in order to identify non-starter bacterial strains with positive effects for possible application as starter culture adjuncts in fermented dairy matrices. Ten (10) independent samples from the Gouda cheese production line at Sanatos Dairies (U) Limited were collected at each of the following stages of production: raw milk, pasteurized milk, non-spiced Gouda cheese of one week, non-spiced Gouda cheese of one month, and spiced Gouda cheese of one month. The samples were enumerated within 8 h, for total viable counts (TVC), yeast and molds, total Lactococci, Staphylococcus spp., total coliforms/E. coli and total LAB using standard protocols. After enumeration of plates, colonies with different morphologies were purified (isolated) and examined for cell morphologies, Gram reaction and biochemical characteristics for presumptive identification and subsequently speciated the bacterial isolates using 16S rDNA sequence analysis. The dominant species were examined for genetic diversity using Unweighted Pair Group Method with Arithmetic Mean (UPGMA) clustering. Selected isolates from each of the major clusters were evaluated for antimicrobial activity, growth, acid and aroma production capacity in Ultra High Temperature (UHT) milk in order to prospect their possible application as starter culture adjuncts in fermented milk. LAB (2.34 - 7.77 log CFU/g) dominated the microflora of raw milk and cheese samples. TVC in respective samples corresponded with LAB counts implying that LAB were the major organisms in different samples examined. Of the 125 microbial isolates, 121 (96.8%) were found to be bacteria and were presumptively identified as Staphylococcus spp. (26.5%), Streptococcus, or Enterococcus (23.9%), Klebsiella, Enterobacter, Eschericia coli, Salmonella, Proteus, Serratia, or Yersinia (19%), Bacillus, Streptomyces, Listeria or Corynebacterium (9.9%) and Lactobacillus or Clostridium were 14.1%. 16S rDNA sequence analysis delineated 28 species with Lactococcus lactis (12.5%), Streptococcus lutetiensis (8.8%) and Lactobacillus plantarum (5%) being the major LAB species detected in all cheese samples; the rest of the isolates were either spoilage or pathogenic bacteria that could have found their way into the cheese post production. UPGMA clustering of these organisms associated them according to their different species and source of isolation; L. lactis from non-spiced Gouda cheese matured for one week were clustered together with L. lactis from spiced Gouda cheese matured for one month implying similar genetic relatedness. Each of the S. lutetiensis and L. plantarum clusters were only obtained from spiced Gouda cheese matured for one month. Thus, Lactococcus lactis and Lactobacillus plantarum were evaluated further for growth, antimicrobial activity against selected pathogenic bacterial strains, acid and aroma production properties. Single and mixed cultures of these organisms had similar growth patterns. All isolates inhibited E. coli, Salmonella and S. aureus on solid media assays but only one isolate of Lc. lactis (Gw-05) inhibited E. coli and Salmonella in the cell-free supernatant assay. In single culture, Lc. lactis had better acid production properties than Lb. plantarum. Mixed of these organisms enhanced acid production. During short term ripening, L. plantarum synthesized more organic acids, ketones, esters and aldehydes (13.7%, 2.3%, 9.3%, and 0.8%, respectively) than L. lactis which mostly produced organic acids and esters (38.7%, 6.6%, respectively). Co-culture of these organisms inhibited aroma production; only three organic acids and one ester were produced. During long term ripening, each of L. lactis and L. plantarum only produced organic acids and esters. However, L. plantarum produced more esters than L. lactis. Co-culture of the organisms enhanced aroma production resulting from synthesis of organic acids, esters and one ketone. It was therefore concluded that LAB dominate the microflora of Gouda cheese production. L. lactis has better prospects for application as primary starter culture in dairy products because they promote rapid acidification of milk, which is desirable for curd formation. Short-term fermentation of milk by single culture of L. lactis and L. plantarum enhance aroma production, while long term ripening enhances aroma production in mixed culture. Single cultures of these organisms could therefore enhance aroma formation in yoghurt, which requires short-term fermentation, whereas mixed culture could be applied in cheese, which requires long-term ripening.
Assessing games teachers' competence in training kids athletics events in primary schools in soroti city, Uganda
(Kyambogo University [unpublished work], 2023-09) Opio, Nicholas
This study assessed games teachers' competence in training kids' athletics events in primary schools in Soroti City, Uganda. The study looked at the competence of games teachers in relation to the selection and use of appropriate materials in training kid's athletics events, establish the games teachers' competence to organize and demonstrate kids' athletics events, assess challenges that affect games teachers in training kids' athletics and suggest way of mitigating the challenges that affect games teachers' competence in training kids' athletics events in Soroti City. The study was carried out to 36 Games Teachers and two hundred sixteen (216) pupils throughout eighteen (18) chosen primary schools in Soroti City, Uganda. The schools were purposefully selected and the participants were games teachers and Pupils between (7 to 14) years, this mixed methods study employed a descriptive cross-sectional design. Interviews, questionnaires, and observations were used to gather data. Statistical Packages for Social Scientists (SPSS) software was used to conduct a descriptive analysis of the data. Frequency distributions, percentages and mean tables, were used to illustrate the findings. The study results showed that game teachers knew how to choose materials and other supplies for Kids' Athletics. The teachers were competent in organizing and demonstrating shot-put (M=2.94 ±SE= 0.18), event compared to other selected activities. The major challenges observed in the study were lack of training courses and equipment that affect the training of kid's athletics programme. The study recommends that the best way to address the issues mentioned is to provide equipment and refresher courses.
Assessing the radiological hazards due to radionuclides in sediments and tailings around Kilembe copper mines, Western Uganda
(International Journal of Environmental Analytical Chemistry, 2024-03-19) Evarist, Turyahabwa R. S.; Farooq, Kyeyune; Eric, Mucunguzi; Akisophel, Kisolo; Manny, Mathuthu
Copper mining in Kilembe Valley, Western Uganda, between 1956 and 1982 resulted in multiple tailing sites, raising concerns about potential increases in the natural background radiation. In this study, the radioactivity concentrations of 226Ra, 232Th, and 40K in 31 sediments and tailing samples from the Kilembe copper mines area were determined using HPGe-based gamma spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K in sediment samples were 38.6 ± 8.9, 37.4 ± 7.8, and 708.0 ± 147.3 Bq kg−1, respectively. While in tailing samples, the mean values were 171.3 ± 31.7, 34.8 ± 14.9, and 792.4 ± 208.2 Bq kg−1, respectively. These values exceeded global averages of 35, 30, and 400 Bq kg−1 for 226Ra, 232Th, and 40K, respectively. To assess the radiological hazards due to radionuclides in sediments and tailings, several parameters such as the radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), gamma representative index (Iγ), absorbed dose rate (D), total annual effective dose (Etot), and total excess lifetime cancer risk (ELCRtot) were determined. In sediments, most of these hazard parameters were above the world’s average values, except Raeq, Iγ, Hex, and Hin. While in tailings, all the hazard parameters surpassed the global average values except Raeq and Hex. Pearson correlation coefficient and hierarchical cluster analysis showed that 226Ra was the main contributor to the assessed radiological hazards. The study suggests potential radiological risks linked to natural radioactivity from sediments and mine tailings, especially when used as building materials.
Assessment of levels, speciation, and toxicity of trace metal contaminants in selected shallow groundwater sources, surface runoff, wastewater, and surface water from designated streams in lake Victoria Basin, Uganda
(Journal of Environmental and Public Health, 2019-05) G. K., Bakyayita; A. C., Norrström; R. N., Kulabako
The levels, speciation of elements, and toxicity of selected trace metals as well as other parameters in selected surface water, shallow groundwater sources, landfill leachate, and associated surface runoff in the Lake Victoria basin, Uganda, were studied. The WHO guidelines, Ugandan standards, Canadian guidelines and Swedish EPA were used for assessment. The shallow groundwater was acidic with pH values below 6.5. The pH, dissolved organic carbon, flouride, and sulphate levels for all springs were below the guideline values although 52.8% was contaminated with nitrates while 39% was contaminated with chloride ions. Some surface water samples had levels of major elements, such as iron, chromium, aluminium, and manganese, above the guideline values. Speciation studies showed that 74% of the metal ions was bound to dissolved organic matter in surface water, whereas in landfill leachates, the dominant ionic species was metal hydroxides or fulvic acid bound. Risk analysis based on the Swedish EPA showed varied risks of negative effects in 30%–76% of the sample sites ranging from high to increased risk in surface water, whereas the results from modelling sorption data using the Bio-met tool showed potential risk to toxicity effects of Cu2+, Ni2+, Zn2+, and Pb2+ in 15.3%–30.8% surface water samples and 8.3%–62.5% groundwater samples.
Assessment of selected health related fitness components of the Uganda Police Force from the Central region of Uganda
(Kyambogo University(Unpublished work), 2009-08) Balagana, Charles G. M.
This study was conducted in the Police force from the central region of Uganda. The objectives of the study were: to establish the fitness levels of the Uganda Police force with regard to selected fitness variables and to ascertain the relationship between duty performance and the selected fitness variables in the police force. Four (4) health related physical fitness components were assessed and these are: Aerobic endurance, Flexibility, Strength endurance and Percent body fat. The sample comprised of 60 subjects split equally between the Traffic police and the Riot police departments. A pre-experimental research design was used in this study. Purposive sampling procedure was employed in selecting the Police Departments. Stratified random sampling procedure was used in selecting the subjects and simple random sampling technique was used to choose the subjects per their duty stations, within the same department and of the same gender. The results were then compared to the already established norms as published by the American Alliance for Health, Physical Education, Recreation and Dance (AAHPERD 1985). Fitness tests for each of the selected fitness components were carried out and the data obtained was compared with the norms as established by AAHPERD (1985). There after, the data was analyzed using the analysis of variance (ANOV A) method in order to test the research hypotheses. For the aerobic condition, 73.3% from the traffic police department and 53.3% from the riot police department showed bad aerobic condition. For strength endurance levels; 60% of the subjects from the traffic police department scored strength endurance levels below average while 50% of the subjects from the riot police department scored above average. On the side of flexibility scores; 66.6% of the total sample from the riot police department had flexibility scores above the average mark while 50% of the total sample from the traffic police had their flexibility scores above the average mark. The flexibility scores from both the riot and traffic police departments therefore put all the subjects within the acceptable range. Body composition results revealed that there was no subject that was over fat from both the riot and traffic police department. It was recommended that regular fitness test programmes should be initiated in the Uganda police force.
Assessment of the cold chain capacity used in bulk handling of perishable agricultural produce in Uganda
(Kyambogo University [unpublished work], 2023-11) Abaasa, Paula
High food post-harvest losses negate the efforts geared towards improving food security and livelihoods of the population. There has been increased interest in addressing challenges associated with food post-harvest losses in policy circles, academia, and the private sector. Of the several mitigation measures suggested, investment in the food cold chain has been repeatedly pointed out as a solution to extensive postharvest losses worldwide, especially for perishable agricultural produce. This study assessed the cold chain capacity used in bulk handling of perishable agricultural produce (milk, meat, fish, fruits and vegetable) in the 16 cities of Uganda (Arua, Gulu, Jinja, Mbarara, Mbale, Masaka, Hoima, Entebbe, Lira, Kampala, Fort Portal, Kabale, Moroto, Nakasongola, Wakiso, and Soroti). Furthermore, the study monitored temperature and relative humidity management of the cold chain facilities and lastly assessed knowledge, attitude and practices of perishable produce retailers towards the cold chain. A total of 51 cold chain facilities used for bulk handling of perishable agricultural produce were found in 09 out of the 16 cities. These were spread out across the cities of Kampala, Wakiso, Mbarara, Fort Portal, Entebbe, Gulu, Masaka, Soroti and Jinja, with Kampala having the highest proportion (47.37%). The total bulk refrigerated storage space in the 16 cities was 39849.25 m3 serving a total ‘within city’ local population of about 8.8 million people which translates to a refrigerated storage capacity of 4.50 m3 per 1,000 inhabitants. The private sector owned the highest proportion (75.44%) of the cold chain facilities and only 21.05% were publicly owned. Generally, the temperatures of the cold chain facilities were not managed effectively as they varied significantly from the respective set point(s) of the cold rooms over the study period. Majority (51.4%) of the perishable produce retailers had no knowledge of the cold chain and 71.56% reported absence of nearby cold chain storage options. Therefore, there is inadequate refrigerated storage capacity for bulk handling of perishable agricultural produce in Uganda and this presents a need for investment in this sector by both public and private players. Cold chain operators need to actively monitor and manage the cold storage temperature and humidity. Interventions should target sensitization of perishable produce retailers on the paramount importance of cold chain management. These interventions will contribute to reduction of post-harvest losses in perishable agricultural produce.
Assessment of the cold storage capacity used in bulk handling of perishable agricultural produce in Ugandan cities{fr}Évaluation de la capacité d'entreposage frigorifique utilisée pour la manutention en vrac de produits agricoles périssables dans les villes ougandaises
(International Journal of Refrigeration, 2024-06-08) Matia, Mukama; Paula, Abaasa
Investment in the food cold chain has been reportedly identified as a solution to extensive postharvest losses worldwide. However, cold chain investment in the Ugandan food value chain is largely unknown. This study located, characterised, and determined the efficacy of bulk cold storage facilities used in handling perishable agricultural food produce in the 16 city districts of Uganda. Only 9/16 city districts had bulk cold storage facilities, translating to a cold storage capacity of 4.5 m3 per 1,000 inhabitants. The private sector owned the highest proportion by volume (90.3%) of these facilities with the highest volume used for handling multiple perishable products (11,590 m3). Generally, temperature varied significantly from the respective set points in the facilities. Variations were observed for between 1/3 to 3/4 of the logged period above maximum allowable storage temperatures for the different products, showing efficacy lapses. These results indicate investment and management gaps and opportunities in this indelible sector in food value chain by both government and private sector players.

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