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CFD Analysis of Flow Characteristics and Diagnostics of Leaks in Water Pipelines
Full text linkThis research article was published by Engineering, Technology & Applied Science Research volume14 2024This study utilizes Computational Fluid Dynamics (CFD) to generate pressure and flow rate values for the
analysis of flow characteristics and the diagnosis of leaks in inclined pipelines. The Semi-Implicit Method
for Pressure-Linked Equations (SIMPLE) solver in OpenFOAM software was modified to incorporate the
effect of pipe orientation angle. Subsequently, the SIMPLE solver was employed to simulate the flow of
water through the pipe. Leakage rates were observed to vary in magnitude with respect to leak position
and pipe orientation angle, except that leaks close to the flow inlet and pipes with a greater inclination
were associated with higher leakage rates. A mathematical leak model is proposed based on non-
dimensional flow variables and pipe orientation angle. To generate sufficient pressure values and leakage
rates, the CFD simulation was performed 70 times. These values were then incorporated into the
mathematical model for the leak location to be predicted. The proposed method is applicable to the
detection of leakages of varying sizes in pipelines with different orientations. Therefore, knowing the pipe
orientation angle and measurements of inlet flow rate, outlet flow rate, and pressure drop, the model can
be used to precisely locate leaks in a pipeline
Application of a constructed wetland for the removal of antibiotic residue, antibiotic-resistant bacteria, and antibiotic-resistance genes from pharmaceutically contaminated wastewater
Full text linkA Dissertation Submitted in Partial Fulfillment of the Requirements for the award of the Degree of Doctor of Philosophy in Environmental Science and Engineering of the Nelson Mandela African Institution of Science and TechnologyThe significant increases in abundance of pharmaceuticals, antibiotic-resistant bacteria (ARB),
and antibiotic resistance genes (ARGs) in the environment have drawn attention over public
health. The presence of these contaminants in wastewaters is well-documented as a factor
contributing to the decreased potency of antibiotics used in healthcare. These types of
contaminants can be removed from wastewater using a number of techniques, including
phytoremediation, which has demonstrated effectiveness. The removal of these contaminants
by various aquatic plants has been explored, and the results are promising. The aim of this
research was first, to analyze antibiotic resistance patterns of bacteria isolated from hospital
wastewater effluent, which is a consequence of antibiotics occurrence in wastewater. Second,
to investigate the removal of some selected antibiotics from synthetic wastewater in
constructed wetland (CW) planted with Cyperus alternifolius, Canna indica, and one planted
with both of these plant species, as well as the influence of antibiotics on microbial density and
community in CW. Hospital wastewater samples were collected from the Benjamin Mkapa
Hospital in Dodoma, Tanzania, where the hospital's wastewater is treated in a horizontal
subsurface flow CW planted with Typha latifolia before being discharged into the environment.
The results of hospital wastewater analysis showed that bacteria isolated from treated hospital
wastewater were resistant to tested antibiotics and harbored antibiotics resistance genes. These
findings demonstrate that CW can disseminate ARB and ARGs despite hospital wastewater
treatment, which poses a risk to the public's health. In the pilot CW, the system planted with a
single plant species (Cyperus alternifolius) outperformed those planted with mixed plant
species or Canna indica alone in the removal of tested antibiotics from wastewater. This
is supported by the observation of higher bacteria abundance in CW with Cyperus altenifolius
than Canna indica, while the difference was not significant (p > 0.05). The findings of this
investigation revealed that although there is a general decline in bacteria abundance, there is
no significant change (p > 0.05) due to antibiotic presence in wastewater. It is concluded that,
despite variations in performance, the plants studied play a significant role in pharmaceuticals
remediation from wastewate
Utilizing tilapia fish skin biomaterial for burn wound dressing: A systematic review
No full textThis research article was published by Scientific African, Volume 24, 2024Burn wound management remains a burden in our hospitals with more than 180,000 people
dying annually due to burn-related complications. Bacterial infections further affect the healing
duration of the wound hence most treatment modalities have aimed at maintaining aseptic
conditions on the wound. Silver sulphadiazine (SSD) cream 1 % has demonstrated the ability to
bind to bacteria cell walls, its amino acids and DNA, and interferes with its respiratory chain
resulting in bacteria death. SSD is considered the gold standard treatment of burn wounds despite
its shortfalls in the treatment of burns. As a result, recent studies have focused on finding better
burn treatment alternatives. Traditional wound dressings like gauze, lint, bandages, and cotton
wool are being replaced by modern wound dressings like hydrogels, alginates, and membranes.
Despite that these modern dressings provide a moist environment to necessitate wound healing,
they also have disadvantages including limited exudate absorptive capacity and lack of antimi-
crobial effect. Alternatively, the use of tilapia fish skin biomaterial has gained interest over the
past years in the treatment of burn wounds. Its usage has been attributed to its high percent
composition of collagen type I and III and its ability to influence cell proliferation, differentiation,
migration, and synthesis of other proteins on the wound site. In this review, we focus on the
various roles that the tilapia fish skin has played in burn wound treatment applications. We
discuss how the tilapia fish skin biomaterial has been tailored to be used in different forms of
wound dressings and how its processed products have been utilized in treating burns. In this
review, we also make a proposition on how the tilapia fish skin biomaterial can be enhanced to be
an effective treatment modality for burn wounds
Characterization of phenotypic traits associated with anthracnose resistance in selected common bean (Phaseolus vulgaris L.) breeding material
Full text linkA research article was published by Heliyon, volume 10 (2024)Anthracnose caused by Colletotrichum lindemuthianum is the major common bean disease worldwide causing complete yield loss under favourable disease conditions. This study aimed to determine phenotypic traits associated with anthracnose resistance for future use in breeding programmes. Twenty-two common bean varieties (CBVs) were selected basing on susceptibility to anthracnose, advanced breeding lines, improved variety resembling advanced breeding lines and the farmer variety widely grown in Tanzania. Selected varieties were planted in anthracnose hotspot fields and the same CBVs were planted in a screen house to validate resistance to anthracnose. Anthracnose infection score, leaf length, leaf width, length of fifth internode, length of petiole, plant vigour, canopy height and canopy width were recorded. Data on number of plants emerging; days to flowering; days to maturity; plant stands at harvest; and grain yield were also collected and analysed using R software. Phenotypic traits evaluated differed significantly among genotypes, environment and genotype by environment interaction. Seventy-five percent of phenotypic traits evaluated were positively correlated to anthracnose resistance.
Highly-strong correlations to anthracnose were observed on number of days to maturity, plant stands at harvest, plant vigour and grain yield. Leaf length, leaf width, length of fifth internode, length of petiole and number of stands emerging were strongly correlated to anthracnose resistance. Additive main effects and multiplicative interaction analysis (AMMI) revealed highest contribution of environment on anthracnose infection-58.9% and grain yield −84.9% compared to genotype effects on anthracnose infection −32.7% and grain yield-15.7%. Based on these results, four traits – plant vigour, number of days to maturity, number of plant stands at harvest and grain yield – are recommended for selecting anthracnose-resistant varieties. NUA 48, NUA 64 and RWR 2154 were superior varieties, resistant to anthracnose and high yielding, while Sweet Violet and VTT 923-23-10 were most stable varieties across environments. Further on-farm research is suggested to assess their performance and identify traits preferred by farmers
The randomness and uncertainty in dynamics of lymphatic filariasis: CTMC stochastic approach
Full text linkThis Research Article was published by the The European Physical Journal Plus:Volume 139, article number 162, (2024)Lymphatic filariasis represents the primary cause of long-term, permanent disability, and dysfunction in the human immune system. In this study, we have devised and assessed deterministic and continuous-time Markov chain (CTMC) stochastic models to gain insights into the dynamics of lymphatic filariasis and approximate the probabilities of disease extinction or outbreak. The CTMC stochastic model is an adapted version of the existing deterministic model that accounts for uncertainties and variations in disease transmission dynamics. The findings from the deterministic model indicate that disease extinction is possible when , while an outbreak is likely when . Further examination of the deterministic model emphasizes the significant role of asymptomatic individuals in the transmission of lymphatic filariasis. To estimate the probabilities of disease extinction or outbreak, we employed multitype branching processes and numerical simulations. The results demonstrate that lymphatic filariasis outbreaks are more probable when microfilariae parasites are introduced by exposed humans, asymptomatic humans, acutely infected humans, exposed mosquitoes, or infectious mosquitoes. Conversely, the disease is more likely to be eradicated if it originates from chronically infected humans. Utilizing stochastic methods provides a more authentic portrayal of how lymphatic filariasis spreads, granting a better understanding of the spectrum of potential results and their related probabilities. Therefore, stochastic CTMC models become indispensable for generating reliable forecasts and well-informed choices in situations where deterministic models might oversimplify or inaccurately depict the inherent unpredictability
Parameters estimation, global sensitivity analysis and model fitting for the dynamics of Plutella xylostella infestations in a cabbage biomass
Full text linkThis research article was published by Chaos, Solitons & Fractals: X,Volume 12, 2024Plutella xylostella, commonly called Diamondback moth (DBM), a highly destructive and rapidly spreading
agricultural pest originally from Europe. This pest poses a significant threat to global food security, with estimates
suggesting that periodic outbreaks of Diamondback moth lead to annual crop losses of up to $US 4 − 5 billion
worldwide. Given the potential for such substantial losses, it is crucial to employ various methods and techniques
to understand the factors affecting the interaction between Diamondback moths and cabbage plants, which,
in turn, impact cabbage biomass. In this paper, we propose a deterministic ecological model to capture the
dynamics of Plutella xylostella infestations in cabbage biomass. The model is designed based on the life cycle
stages of the pest, aiming at targeting the specific stage effectively. The synthetic data is generated using Least
Square Algorithm through addition of Gaussian noise into numerically obtained values from existing literature
to simulate real-world data. Global sensitivity analysis was done through Latin Hypercube sampling, highlights
the significance of parameters such as , and positively influence the growth of the diamondback moth in
a cabbage biomass. In light of these findings, the study proposes that control strategies should be specifically
directed towards these sensitive parameters. By doing so, we mitigate the pest population and enhance cabbage
production
Future Trade-Off for Water Resource Allocation: The Role of Land Cover/Land Use Change
Full text linkThis research article was published in the Journals Water,Volume 16, Issue 3, 2024Global croplands, pastures, and human settlements Have expanded in recent decades.
This is accompanied by large increases in energy, water, and fertilizer consumption, along with
considerable losses of biodiversity. In sub-Saharan Africa, policies are implemented without critical
consideration; e.g., agricultural expansions impair ecosystem services. We studied land use/cover
and the associated rate of change for four time epochs, i.e., 1991, 2001, 2011, and 2021. This employed
remote sensing and GIS techniques for analysis, while future projections were modeled using cellular
automata and the Markov chain. The kappa coefficient statistics were used to assess the accuracy
of the final classified image, while reference images for accuracy assessment were developed based
on ground truthing. Overall change between 1991 and 2021 showed that major percentage losses
were experienced by water, forest, woodland, and wetland, which decreased by 8222 Ha (44.11%),
426,161 Ha (35.72%), 399,584 Ha (35.01%), and 105,186 Ha (34.82%), respectively. On the other Hand,
a percentage increase during the same period was experienced in cultivated land, built-up areas, and
grasslands, which increased by 659,346 Ha (205.28%), 11,894 Ha (159.93%), and 33,547 Ha (98.47%),
respectively. However, this expansion of thirsty sectors Has not reversed the increasing amount of
water discharged out of the Kilombero River catchment. We recommend the promotion of agroforests
along with participatory law enforcement and capacity building of local communities’ institutions
Knowledge and practices related to plague persistence in plague-endemic foci, Mbulu District, Tanzania
Full text linkThis research article was published by PLOS NEGLECTED TROPICAL DISEASES,In 2024Plague continues to be a major public health concern in African countries. Several social
practices and environmental conditions have been associated with the reoccurrence of
bubonic plague, especially in places where the disease is prevalent. Therefore, it remains
important to understand people knowledge, behavior and practices related to disease risks
in order to identify factors that may hinder prevention and control strategies in the foci
Electrical power output potential of different solar photovoltaic systems in Tanzania
Full text linkThis research article was published by International Journal of Renewable Energy Development,in 2024This study examines the photovoltaic (PV) energy output and levelized cost of energy (LCOE) in seven regions of Tanzania across five
different tilt adjustments of 1 MW PV systems. The one-diode model equations and the PVsyst 7.2 software were used in the simulation. The results
reveal variations in energy output and LCOE among the regions and tilt adjustments indicating a strong correlation between PV energy output and
solar irradiance incident on the PV panel. For horizontal mounting, the annual energy output ranges from 1229 MWh/year in Kilimanjaro to 1977
MWh/year in Iringa. Among the three optimal tilt adjustments, annually, monthly and seasonal, the last two are predicted to yield larger energy
outputs, whereas the two axis tracking configuration consistently provides the maximal energy output in all regions, ranging from 1533 MWh/year
in Kilimanjaro to 2762 MWh/year in Iringa. The LCOE analysis demonstrates the cost-effectiveness of solar PV systems compared to grid-connected
and isolated mini-grid tariffs. The LCOE values across the regions and tilt adjustments range from 0.16/kWh. In comparison, the tariff
for grid-connected solar PV is 0.181/kWh. The monthly optimal tilt configuration proves to be the
most cost-effective option for energy generation in multiple regions, as it consistently exhibits the lowest energy cost compared to the other four
configurations. The results provide valuable insights into the performance and economic feasibility of various system setups. Through meticulous
simulation and data analysis, we have gained a comprehensive understanding of the factors influencing energy generation and costs in the context of
solar photovoltaic system
Prevalence and Risk Factors of Human Taenia solium Cysticercosis in Mbulu District, Northern Tanzania
Full text linkThis research article was published by MDPI,2024.Background: Taeniosis and cysticercosis are human infections caused by the pork tapeworm,
Taenia solium. This study is a baseline for community-based intervention. We determined the
prevalence of human cysticercosis and associated risk factors following a deworming program
conducted throughout the country, with Mbulu District being among the districts in Northern
Tanzania. Methods: Human cysticercosis was determined by enzyme-linked immunosorbent assay
(Ag- ELISA). Household interviews and observations were conducted to identify risk factors for
cysticercosis transmissions among households and communities. Results: Three hundred individuals
participated in this study. The age ranged from 5 to 89 years, with a median of 19 years. The
prevalence of human cysticercosis was 23 (7.67%). The prevalence was high with 6 (11.76%) among
individuals aged 26 to 35 years and ±45 years. There was no statistically significant difference in the
prevalence by age group, sex, or occupation. Among the 300 participants, 82 (27.3%) had received
anthelmintics during the previous year; among these, 5 (21.7%) were infected. The likelihood of
infection was low among anthelmintic users by 28% [0.72 (0.26–2.01)], but the protection was not
significant. The communities differed in risk factors on the availability of a clean and safe water
supply; 52.7% (46/86) of households visited had no pit latrine. The cysticercosis prevalence showed
a significant difference in communities. Conclusions: The prevalence of human cysticercosis was
high and associated with higher age groups. The prevalence was low among those who had taken
anthelmintics and was associated with lower age groups. The current school deworming program
has a positive effect on school children, while the elderly are at higher risk because the intervention
did not target them. It is recommended to scale up anthelmintic intervention to higher age groups