2647 research outputs found
Sort by
Rodent abundance, diversity and community structure in a bubonic plague endemic area, northern Tanzania
Get PDFA research article was submitted to journal MammaliaRodent-borne diseases such as bubonic plague remain a significant threat to public health in tropical countries. In plague-endemic areas, little information exists on the factors triggering periodic bursts, thus rendering preparedness strategies for preventing the negative impacts of the deadly zoonosis difficult. In this study, we assessed how species richness, diversity, and community structure of rodents are associated with plague persistence in Mbulu District, Tanzania. Rodent data were collected using the removal trapping technique. We captured 610 rodents belonging to 12 species, with Mastomys natalensis recording highest abundance. There was significantly higher abundance and species richness in persistent than non-persistent plague locality. Also, house premises recorded significantly lower species richness than farm and forest habitats. Additionally, we found three broad rodent community structures that varied significantly between studied habitat types suggesting high rodent populations interaction at fine-scale resource abundance. The high abundance and diversity of plague-susceptible rodent reservoirs suggestively contribute to the plague persistence in the foci. These results may be useful to developing preparedness strategies in these areas to control plague outbreaks
Time series and ensemble models to forecast banana crop yield in Tanzania, considering the effects of climate change
Get PDFA research article was submitted to Resources, Environment and Sustainability Volume 14, December 2023Banana cultivation plays a pivotal role in Tanzania’s agricultural landscape and food security. Precisely forecasting banana crop yield is essential for resource optimization, market stability, and informed policymaking, particularly in the face of climate change. This study employed time series and ensemble models to forecast banana crop yield in Tanzania, offering crucial insights into future production trends. We utilized Seasonal ARIMA with Exogenous Variables (SARIMAX), State Space (SS), and Long Short-Term Memory (LSTM) models, chosen based on regression analysis and data exploration. Leveraging historical banana yield data (1961–2020) and relevant climate variables, we formulated an ensemble model using a weighted average approach. Our findings underscore the potential of time series and ensemble models for accurate banana crop yield forecasting. Statistical evaluation metrics validate their effectiveness in capturing temporal variations and delivering reliable predictions. This research advances agricultural forecasting by demonstrating the successful application of these models in Tanzania. It emphasizes the importance of considering temporal dynamics and relevant factors for precise predictions. Policymakers, farmers, and stakeholders can leverage this study’s outcomes to make informed decisions on resource allocation, market planning, and agricultural policies. Ultimately, our research bolsters sustainable banana production and enhances food security in Tanzania
Rheological and physicochemical analysis of non- edible oils used for biodiesel production
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Masters of Science in Sustainable Energy Science and Engineering of the Nelson Mandela African Institution of Science and TechnologyThe knowledge of the physicochemical and rheological flow characteristics of biodiesel
feedstock is used for quality control in production, storage and transportation processes.
Moreover, the knowledge is applied in redesigning and optimizing facilities that can be used
for manufacturing, storage and transportation of the fuel. Non-edible oils analysed in the
present study were Cashew Nut Shell Liquid (CNSL), Castor Oil (CO), croton megalocarpus
oil (CMO), podocarpus usambarensis oil (PUO) and Thevetia peruviana oil (TPO). Free fatty
acid, acid value, saponification value, peroxide value, iodine value, specific gravity and
moisture content were determined by following the recommended Association of Official
Analytical Chemists (AOAC) methods of analysing physicochemical characteristics.
Physicochemical results show that all the selected non-edible vegetable oils with an exception
of CNSL, do not require any further treatment. However, due to high Free Fatty Acid (FFA)
content in CNSL, direct biodiesel production from the feedstock would be a challenge hence
further treatment to reduce the acidity of the feedstock is essential. Rheological flow parameters
were analysed using VT-550 Thermo Haake Viscotester monitored by a Rheowin Job manager.
The pre-set parameters in the Viscotester were the shear rate and temperature. The shear rate
was increased uniformly from 5 −1 –100 −1 in 60 seconds at 30-60˚C. Regardless of the
analysis temperature, all oils exhibited Newtonian flow behavior, indicating that the viscosity
of the oil remained uniform at a constant temperature. The experimental data were fitted into
rheological models: Newton, Bingham, Oswald de Waele (power-law), and Herschel Bulkley
using Rheowin data evaluation software. The results revealed that Newton and Oswald de
Waele models were appropriate to represent the flow behaviour of the oils with the fit of R2 ≥
0.990
Experimental investigation of the variation in the potential of selected natural rocks as thermal energy storage materials
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Master of Science in Sustainable Energy Science and Engineering of the Nelson Mandela African Institution of Science and TechnologyFossil fuels cause greenhouse gas emissions and are perceived to deplete, hence the use of
renewable energy is considered crucial. These renewables include the use of solar thermal
energy in concentrated solar power (CSP) generation and solar drying applications. However,
solar energy is intermittent, thus solved by incorporating thermal energy storage (TES) to store
heat energy for future use. However, the most common weaknesses in TES materials are high
cost of investment, environmentally unfriendly and are not locally available. Using natural
rocks is recommended as they are readily available, affordable and efficient TES materials for
solar drying applications at 40-75 °C and concentrated solar power generation at 500-600°C.
Despite its generational use in thermal applications, soapstone rock has not been studied as a
TES material. Moreover, site specificity has not been investigated in spite of being stated to
affect the potential of rocks in TES. Therefore, this study investigates the potential of soapstone
rock as a TES material, and the influence of the geological-tectonic settings. In the present
study, experimental characterization of selected natural rocks namely soapstone and granite,
was done to investigate their thermal properties at 20-950°C. Conclusively, soapstone rock
from the Craton geo-tectonic setting had the best properties and it had the highest young’s
modulus, thermal capacity, thermal conductivity and had a weight loss of only 0.75 % at 900°C.
At high temperatures, it did not show visible fracture. Moreover, soapstone and granite from
the Craton and Usagaran geo-tectonic settings exhibit significant difference
Risks of snakebite and challenges to seeking and providing treatment for agro-pastoral communities in Tanzania
Get PDFThis research article was published in PLOS ONE, Volume 18, 2023.Continuous occurrence of snakebite incidences and the vulnerability of some communities remain a critical problem in sub-Saharan Africa. Despite causing permanent disability to almost half a million people annually and numerous deaths, snakebite and associated complications are still largely neglected. This study aimed at elucidating risk factors associated with snakebite cases, treatment availability and case management practices for vulnerable agro-pastoralist communities in Northern Tanzania.
Data was collected in the Monduli (Arusha region) and the Simanjiro (Manyara region) districts in Tanzania. Interviews with 101 snakebite victims or their guardians and 13 health professionals from 3 health centers in the districts were conducted. Additionally, case records of patients admitted between 2007 and 2019 to the Meserani Snakebite Clinic were obtained.
This study showed that appropriate treatment for snakebite including anti-venom, is difficult to access and that snakebite incidences were significantly linked to factors such as gender, age, socio-economic activity, season of the year, and whether being at home or out in the fields. Anti-venom and trained health professionals were only available at the Meserani Snake Park Clinic. Men were bitten most often (χ2 = 62.08, df = 4, p-value < 0.0001). Overall, adults between the ages of 18 and 60 years (χ2 = 62.08, df = 4, p-value < 0.0001) received most bites, usually while outdoors herding cattle in the dry season. A significant majority of victims looked for traditional treatment first (52.7%, χ2 = 29.541, df = 2, p-value = 0.0001). The results of this study present crucial information on what is needed to improve the accessibility to appropriate treatment after a snakebite among agro-pastoral communities.
The situation regarding morbidity and mortality due to the inaccessibility of common treatment for snakebite in northern Tanzania is challenging. Reliance on traditional medicine exacerbates the situation. There is dire need to involve affected communities, researchers, the government, clinicians and the public in general, to work together and take part in the global snakebite initiative. Communities and health professionals recognise the underlying challenges and have valuable suggestions on how to improve the situation
Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern Tanzania
Get PDFThis research article was published in Bulletin of Environmental Contamination and Toxicology, 2023Elemental tracer concentrations of copper, lead, nickel and zinc, were assessed in the muscles of Oreochromis amphimelas
and Clarias gariepinus from Lake Manyara, Tanzania, to evaluate their safety to consumers, specifcally humans. Results
revealed that no elemental concentrations exceeded the FAO permissible levels, indicating fsh from all sites are safe for
human consumption. However, based on the highest found concentration of Pb, we recommend a maximum consumption of
2.2 kg of fsh from Lake Manyara per week. No signifcant diferences were observed in the metal concentrations between
the two fsh species, suggesting there is no bioaccumulation in the food chain. Moreover, no signifcant diferences were
found between fsh landing sites, indicating there are no regions in the lake with higher pollution. These fndings indicate
that PTM concentrations have not increased to toxic levels due to increased mobilisation from the catchment. Continued
monitoring of potential toxic metal concentrations in fsh is recommended due to endorheic nature of Lake Manyara and
increasing anthropogenic activities in its catchment area
Influence of phosphate fertilizers on the radioactivity of agricultural soils and tobacco plants in Kenya, Tanzania, and Uganda
Get PDFThis research article was published by Springer Berlin Heidelberg in 2023Three brands of NPK fertilizers that contain variable concentrations of natural radioactivity are commonly used in tobacco
plantations in Kenya, Tanzania, and Uganda. Tobacco plants are known for hyper-accumulation of natural radionuclides,
particularly 238U. This study investigated if the elevated radioactivity in phosphate fertilizers could enhance radioactivity in
soils and tobacco plant leaves. The 232Th, 238U, and 40K radionuclide levels in NPK-fertilized soils and tobacco leaves were
measured using gamma-ray spectroscopy. The research included a one-year reference experiment with tobacco growing in
plots, a ten-year semi-controlled experiment in well-managed tobacco farms, and a field survey of radioactivity in soils and
tobacco leaves at three traditional tobacco fields in Migori (Kenya), Urambo (Tanzania), and Kanungu (Uganda). The findings
demonstrated that soils and tobacco leaves exposed to NPK fertilizers with increased radioactivity had activity concentrations
of 232
Th, 238
U, and 40
K that were considerably higher (at all sites) than in the control samples (with no use of NPK fertilizers).
As the continued application of NPK fertilizers raises concentrations of 232Th, 238U, and 40K in agricultural soils, the study
assessed radiological risks for humans from exposure to agricultural soils enriched with phosphate fertilizers, and it was found
to be below the exposure limit of 1 mSvy-1 suggested by the International Commission on Radiological Protection (ICRP).
However, tobacco consumers, both by snuffing and smoking, may face significant radiological risks, as the snuffing and
smoking resulted in effective doses that were 2.41 to 6.53 and 1.14 to 2.45 times greater than the average yearly dose that the
general public receives from inhalation of natural radionuclides (United Nations Scientific Committee on Atomic Radiations
estimates). Furthermore, the results indicate that the lifetime excess cancer risk for tobacco snuffers and smokers ranged from
5 × 10 -5 to 24.48 × 10 -3 and 2.0 × 10 -5 to 9.18 × 10 -3 , respectively. The influence of phosphorus-derived fertilizer containing
relatively high natural radioactivity, potential human radiation exposure, and radiological risk due to gamma radionuclides
is estimated and discussed. The results reveal that applying phosphate fertilizers enhances natural radioactivity in soil and is
subsequently influenced by soil to tobacco plant uptake. Therefore, the study recommends that countries use fertilizers with
lower radionuclide content to conserve soil quality and reduce gamma-emitting radionuclides in tobacco plants
A quantity-quality tradeoff: Water quality and poverty assessment of drinking water sources in Southern Tanzania
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree Masters in Environmental Science and Engineering of the Nelson Mandela African Institution of Science and TechnologyRegardless of being essential for human survival, access to potable water is still a problem in many
rural African communities with increasing exposure to waterborne illnesses. This study aimed at
establishing accessible quality water sources in 5 drinking water sources in rural southern
Tanzania. The water quality index (WQI) and water poverty index (WPI) were utilized to grade
and measure the water quality and water stress respectively. The 26 households participated in a
socioeconomic survey to gauge the water accessibility in relation to four WPI factors viz.,
preference, accessibility (distance), quality, and seasonal availability. Results from the WPI
computed data revealed that all the investigated water sources possessed poor quality with 222.5
and 112 for surface water and shallow wells (>50 excellent, <300 unsuitable). The WPI scores for
shallow wells were safer than surface water at 45.7 as contrasted to 33.8 for surface water (0-
poorest levels, 100-best levels). This study concluded that, in this area, shallow wells have more
secure water in terms of quality and accessibility. Health data from Milola ward showed high
occurrences of water borne diseases. This study recommends urgent water treatment intervention
by the responsible stakeholders to avail clean, reliable, and accessible drinking water for vulnerable
communities
Does variation in plant diversity and abundance influence browsing intensity in black rhinos?
Get PDFThis research article was published by African Journal of Ecology, Volume61, Issue3, 2023.Variations in forage availability, selection and preferences can lead to intense foraging competition and depletion of food consequently lowering diet quality and population performance of black rhino species. This study investigated seasonal variations in rhino diet, foraging, preference and browsing intensity and how this is influenced by plant diversity and availability in Mkomazi National Park (MKONAPA). Fifty-eight square grids were randomly selected in each season, and plots were laid for vegetation assessment during wet and dry seasons in the sanctuary. Browsed species by rhinos were compared with rhino feeding data from fourteen rhino range areas within Africa. More than 85% of species edible in MKONAPA were similar to those in rhino range areas. Acalypha ornata, Grewia similis and Commiphora africana were highly utilised specie in both seasons. Diversity and abundance of consumed browses decreased towards the dry season while browsing intensity increased with forage preference in both seasons and was prominent when browse availability was low in dry seasons. Our study established seasonal variation in dietary composition, browsing intensity and preferences for black rhinos. We suggest establishing nutritional composition of preferred forages, assessing density of competitor browsers, translocating excess rhinos or expanding the sanctuary to meet the recommended ecological carrying capacity
Iot-based computer laboratory equipment tracking system: a case of Université du lac Tanganyika
Get PDFA Project Report Submitted in Partial Fulfillment of the Requirements of the Award the Degree of Master of Science in Embedded and Mobile Systems of the Nelson Mandela African Institution of Science and TechnologyIn today’s digital age, computer laboratories’ adoption in academic institutions and the security
of equipment are crucial to ensure their effective functioning and prevent equipment loss or
damage. These laboratories have valuable equipment, such as laptops, switches, routers,
projectors, printers, and scanners, that require proper security measures to prevent losses or
damages. Manual methods such as pen and paper, spreadsheets and tracking software have
been commonly used in the past for equipment tracking. However, these approaches have
certain limitations, such as being time-consuming, having limited storage and retrieval abilities,
and not providing real-time updates. To overcome these challenges and enhance the lab
equipment tracking system, the objective of the developed system is to identify the necessary
requirements for designing, developing and validating an IoT-based computer lab equipment
tracking system to manage high-value lab equipment at Université du Lac Tanganyika (ULT)
university and prevent the unauthorised removal of equipment from the laboratory. The study
employs Radio Frequency Identification (RFID) technology to track and identify automatically
tags attached to the equipment. This study used Agile’s Scrum framework as a system
development approach, and a qualitative research approach, including interviews,
observations, and focus group discussions, was used to collect data for the functional and non functional requirements. An ESP32 microcontroller was used to collect and process data from
sensors and send the data to the IoT cloud. An Advanced Encryption Standard (AES)
encryption and decryption algorithm using a 128-bit key was implemented to ensure the secure
transmission of RFID data. The system also features an automatic lock-unlock mechanism to
prevent equipment from moving out of the lab without authorisation. A web application with
a simple interface was developed for the equipment management system. Ultimately, the
system validation process engaged 51 participants comprising IT managers, lab assistants, lab
technicians, and lab users. All participants filled out a system evaluation form which resulted
in positive responses. The results of the system validation analysis indicate an average of 87%
of performance, availability, accuracy, efficiency, and effectiveness. Therefore, ULT
University accepted the system due to its effectiveness, security features, and user-friendly
interface