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Large-scale land acquisitions exacerbate local farmland inequalities in Tanzania
Get PDFThis research article was published by PNAS Vol. 120 | No. 32Land inequality stalls economic development, entrenches poverty, and is associated with environmental degradation. Yet, rigorous assessments of land-use interventions attend to inequality only rarely. A land inequality lens is especially important to understand how recent large-scale land acquisitions (LSLAs) affect smallholder and indigenous communities across as much as 100 million hectares around the world. This paper studies inequalities in land assets, specifically landholdings and farm size, to derive insights into the distributional outcomes of LSLAs. Using a household survey covering four pairs of land acquisition and control sites in Tanzania, we use a quasi-experimental design to characterize changes in land inequality and subsequent impacts on well-being. We find convincing evidence that LSLAs in Tanzania lead to both reduced landholdings and greater farmland inequality among smallholders. Households in proximity to LSLAs are associated with 21.1% (P = 0.02) smaller landholdings while evidence, although insignificant, is suggestive that farm sizes are also declining. Aggregate estimates, however, hide that households in the bottom quartiles of farm size suffer the brunt of landlessness and land loss induced by LSLAs that combine to generate greater farmland inequality. Additional analyses find that land inequality is not offset by improvements in other livelihood dimensions, rather farm size decreases among households near LSLAs are associated with no income improvements, lower wealth, increased poverty, and higher food insecurity. The results demonstrate that without explicit consideration of distributional outcomes, land-use policies can systematically reinforce existing inequalities
Fuzzy modelling on the depletion of forest biomass and forest-dependent wildlife population
Get PDFA research article was submitted to Franklin Open Volume 4, September 2023This paper presents a system of non-linear differential equations describing the depletion of forest biomass and forest-dependent wildlife population caused by human population and its associated activities. The model incorporates the imprecise nature of the parameters, which are treated as triangular fuzzy numbers to reflect the inherent uncertainty. We utilised cut to transform these imprecise parameters into intervals. Subsequently, employing the principles of interval mathematics, we effectively converted the related differential equation into a pair of distinct differential equations. By leveraging the signed distance of the fuzzy numbers, we further simplified the equations, resulting in a single differential equation, which led to the formulation of a defuzzified model. The existence of equilibrium points with their stability behaviour is presented. Furthermore, the existence of trans-critical bifurcation is analysed. Through numerical simulations, we observe significant differences between the solutions of system in crisp and fuzzy environments. These findings highlight the importance of using fuzzy models to accurately represent the dynamics of complex natural systems. Consequently, we conclude that fuzzy models provide a trustworthy representation of the dynamics of complex natural systems
A mobile application for research knowledge sharing and dissemination: the case of Monduli and mto wa mbu Arusha
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Master’s in Information and Communication Science and Engineering of the Nelson
Mandela African Institution of Science and TechnologyScientific publications continue to be the primary mode of disseminating research findings
from universities. Although appropriate for other scholars, the method is not accessible to the
general public and policymakers, as the language used is often technical and assumes
knowledge of the theories and techniques in the field, while recommendations focus on further
scientific investigations rather than how to implement findings in real-world settings.
Additionally, the vast majority of publications are not open access and thus require either
paying an average of 16 000
for institutional access to various publications. Evidence-based decision-making is a pillar for
sustainable development, and therefore, this accessibility gap can have major implications for
achieving development goals. Recently, researchers have utilized platforms such as personal
websites, social media, blogs, and other ICTs to disseminate the key findings of their research
in a succinct and non-technical format. Field dissemination methods such as workshops are
also increasingly utilized, especially in low-resource communities. However, field methods can
be costly and do not provide community members with long-term, repeated access to the
presented information and to newer findings on the same topic. In this study, we aimed to
determine how mobile technologies can be effectively utilized for continuous knowledge
dissemination from researchers to low-resource communities. As a case study, we used the
Monduli and Mto wa Mbu areas in Arusha, Tanzania, and the communities participating in 5
VLIR-UOS projects from NM-AIST, spanning from soil fertility to land use mapping. A user centered design approach was used to determine the requirements from the researchers,
community members, and government extension officers (n = 106). The results indicate that
the application has the potential to enhance research collaboration and dissemination at
Monduli and Mto wa Mbu, and provide insights into the challenges and opportunities
associated with the use of mobile technologies for research knowledge sharing and
dissemination in academic contexts
Removal of heavy metals from binary and multicomponent adsorption systems using various adsorbents – a systematic review
Get PDFThis research article was published in Journals Research Society of Chemistry Volume13, Issue19,2023The ecosystem and human health are both significantly affected by the occurrence of potentially harmful
heavy metals in the aquatic environment. In general, wastewater comprises an array of heavy metals, and
the existence of other competing heavy metal ions might affect the adsorptive elimination of one heavy
metal ion. Therefore, to fully comprehend the adsorbent's efficiency and practical applications, the
abatement of heavy metals in multicomponent systems is important. In the current study, the
multicomponent adsorption of heavy metals from different complex mixtures, such as binary, ternary,
quaternary, and quinary solutions, utilizing various adsorbents are reviewed in detail. According to the
systematic review, the adsorbents made from locally and naturally occurring materials, such as biomass,
feedstocks, and industrial and agricultural waste, are effective and promising in removing heavy metals
from complex water systems. The systematic study further discovered that numerous studies evaluate
the adsorption characteristics of an adsorbent in a multicomponent system using various important
independent adsorption parameters. These independent adsorption parameters include reaction time,
solution pH, agitation speed, adsorbent dosage, initial metal ion concentration, ionic strength as well as
reaction temperature, which were found to significantly affect the multicomponent sorption of heavy
metals. Furthermore, through the application of the multicomponent adsorption isotherms, the
competitive heavy metals sorption mechanisms were identified and characterized by three primary kind
The Application of Online and Blended Learning During Outbreaks, Epidemics and Pandemics: The Case of Higher Education Institutions (HEIs)
Get PDFA research article was published by Emerald insightIn 2020, the Covid-19 pandemic resulted in full or partial lockdowns of higher education institutions (HEIs) in most countries worldwide. On the other hand, HEIs around the world were faced with the difficult questions of how to continue to provide training, learning and research activities to students during outbreaks, epidemics and pandemics. Online and blended learnings are relatively new modes of teaching and learning activities which enable HEIs to offer either online only or a combination of online and physical-based programs of study respectively. Adoption of such learning practices helped ensure continued HEIs operations during outbreaks, epidemics and pandemics. However, there are HEIs which still have no or limited investment in online and blended learning. This chapter outlines the different models of online and blended learning that HEIs can adopt, demystify the benefits, values and challenges posed by these models, necessary infrastructure including information and communication technologies (ICTs) as well as required staff and student support services to ensure effective and efficient uptake and usage. It further shows that with a deliberate initial investment in the necessary infrastructure, staff and student support services, the resources of and potential for online and blended programs can be enormous. It also outlines remote learning models that HEIs can adopt, how to support students’ readiness for online and blended learning, the benefits and challenges posed by employing online and blended learning in HEIs and the necessary infrastructure and support services
Mathematical modeling of vaccination as a control measure of stress to fight COVID-19 infections
Get PDFA research article was published by Chaos, Solitons & Fractals Volume 166, January 2023The world experienced the life-threatening COVID-19 disease worldwide since its inversion. The whole world
experienced difficult moments during the COVID-19 period, whereby most individual lives were affected by the
disease socially and economically. The disease caused millions of illnesses and hundreds of thousands of deaths
worldwide. To fight and control the COVID-19 disease intensity, mathematical modeling was an essential tool
used to determine the potentiality and seriousness of the disease. Due to the effects of the COVID-19 disease,
scientists observed that vaccination was the main option to fight against the disease for the betterment of
human lives and the world economy. Unvaccinated individuals are more stressed with the disease, hence their
body’s immune system are affected by the disease. In this study, the deterministic model of COVID-
19 with six compartments was proposed and analyzed. Analytically, the next-generation matrix method was
used to determine the basic reproduction number (0). Detailed stability analysis of the no-disease equilibrium
(0) of the proposed model to observe the dynamics of the system was carried out and the results showed that
0 is stable if 0 1. The Bayesian Markov Chain Monte Carlo (MCMC) method for
the parameter identifiability was discussed. Moreover, the sensitivity analysis of 0 showed that vaccination
was an essential method to control the disease. With the presence of a vaccine in our model, the
results showed that 0 = 0.208, which means COVID-19 is fading out of the community and hence minimizes
the transmission. Moreover, in the absence of a vaccine in our model, 0 = 1.7214, which means the disease
is in the community and spread very fast. The numerical simulations demonstrated the importance of the
proposed model because the numerical results agree with the sensitivity results of the system. The numerical
simulations also focused on preventing the disease to spread in the communit
Development of dried African nightshade products for post-harvest loss reduction and shelf-life extension in Tanzania
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Master’s in Life Sciences of the Nelson Mandela African Institution of Science and TechnologyAfrican nightshade (ANS) is a luminary food plant, considered a cheap and potential dietary
source for micronutrients and bioactive compounds. Lack of value addition on ANS, results
to high availability of ANS during peak season and shortage in off-season was the great demand
for developing dried products. This study evaluated the effects of drying techniques on
nutritional (minerals & vitamin C) and anti-nutritional (oxalate & phytate) contents of Solanum
scabrum (SS) and S. villosum (SV). Three methods of drying namely indirect solar drying
(ISD), mixed solar drying (MSD), and open sun drying (OSD) were employed. Furthermore,
blanching (85°C, 2 min) with and without 3% salt (NaCl) were used as pre-treatments for ANS.
The effect of pre-treatment methods on nutrient retention and anti-nutrients removal was also
recorded. From the results ISD was the most effective method for vitamin C (14.76% 19.2%),
Ca (92.90%, 96.57%), Fe (77.88%, 71.54%), and Zn (86.94%, 90.09%) retention for both SS
and SV leaves, respectively. On the other hand, all drying methods significantly reduced levels
of oxalate (4.46% to 35.24% ) and phytate (52.12% to 85.55%). Pannelists rated dried ANS
significantly ≤ 0.05 higher for texture, colour, taste, aroma, bitterness and overall acceptability.
Shelf life studies of dried products were stable at ambient and refrigeration storage for a period
of three months with no growth of bacteria, yeast and mold, with significance loss of Vitamin
C under both conditions. The findings showed that the ISD best method for vitamin C, minerals
retention and anti-nutritional reduction
Sero-molecular epidemiological analysis of leptospirosis in smallholder dairy cattle in selected regions of Tanzania
Get PDFA Thesis submitted in Partial Fulfillment of the Requirements for the Degree of Master’s in Life Sciences of the Nelson Mandela African Institution of Science and TechnologyThe smallholder dairy industry in Tanzania is a promising sector for household income
generation despite challenges of zoonosis such as leptospirosis caused by Leptospira serovar
Hardjo. A total of 2086 blood, serum and additional vaginal swab for female cattle were
collected from smallholder dairy cattle for leptospirosis testing using three complementary tests
An overall prevalence of 13%, 13.1% and 13.7% for Leptospira serovar Hardjo by ELISA test,
RT-PCR for pathogenic Leptospira spp. and MAT respectively. Based on ELISA test, the
highest prevalence shown in Iringa 30.2% (95% CI 25.1 - 35.7%) and Tanga 18.9% (95% CI
15.7 - 22.6). In multivariable analysis, factors that were a significant risk in smallholder dairy
cattle are: animals over 5 years of age OR = 1.41 (95% CI 1.05 - 1.90); indigenous breed OR
= 2.78 (95% CI 1.47 - 5.26); hiring or keeping a bull for breeding purposes OR = 1.91 (95%
CI 1.34 - 2.71); distance between farms of more than 100 meters OR = 1.75 (95% CI 1.16 -
2.64); livestock kept extensively (OR = 2.31, 95% CI 1.36 - 3.91); farms without cat for rodent
control (OR = 1.87, 95% CI 1.16 - 3.02); farmers with livestock training OR = 1.62 (95% CI
1.15 - 2.27); temperature (OR = 1.63, 95% CI 1.18 - 2.26), and the interaction of higher
temperature and precipitation (OR = 1.5, 95%CI 1.12 - 2.01). This findings provide an
opportunity for future study to include a broad serogroups panel for more identification of
common serogroups circulating in cattle for vaccine target in Tanzanian cattle population
Climate change impacts outweigh conservation efforts in coral reefs that are highly exposed to thermal stresses in Zanzibar, Tanzania
Get PDFThis research article was submitted to Ocean & Coastal Management Volume 238, 1 May 2023With a greater range of management practices and so many threats to coral reefs, assessing coral reef resilience using social-ecological approaches is an important way towards understanding the climatic and non-climatic impacts, and proper conservation efforts in coral reefs. In this study, six reefs (Changuu, Chapwani, Chumbe, Kizimkazi, Mnemba East and Mnemba West) were selected as case study sites to explore resilience potential of coral reefs in Zanzibar in relation to contrasting conservation strategies. Data were collected through household surveys, key informant interviews and biological survey (line-intercept transect and direct observations). Results showed that, Chumbe reefs was perceived to be highly protected followed by Kizimkazi reefs, while Changuu and Chapwani were considered to be less protected. Fishing pressure, climate change, inadequate management and pollution were regarded as the most critical drivers of coral reefs degradation. Coral bleaching was identified to be a main cause of coral reef damage by communities in Chumbe and Mnemba East, whereas inadequate management, pollution and uncontrolled tourisms were identified as the major driver by those in Changuu and Chapwani. Overall, reefs from Kizimkazi was found to have the highest resilience potential as it is under community-based conservation compared to other reefs. We conclude that coral reef resilience is context-specific and influenced by multiple factors, and although conservation efforts have a positive impact on coral reef health, climate change effects outweigh conservation efforts in reefs that are highly exposed to thermal stresses, such as the Chumbe and Mnemba East reefs. We recommend further promotion of viable alternative livelihood activities to reef reliant communities and collaborative management for the improvement of corals' resilience and conservation in the study area
IoT-based on boiler fuel monitoring system: A case of Raha Beverages company limited, Arusha-Tanzania
Get PDFThis research article was published in Research Square journal in 2023.RAHA Beverages Company (RABEC) is one of the banana wine production companies that utilize fuel in
steam production in Arusha-Tanzania where fuel data conditions like temperature, pressure, discharge, fuel level, and
gas leakage with humidity were a challenge to monitor them which provoked boiler malfunction and plant breakdown.
Today, RABEC manually uses a dropping stick into the fuel tank to monitor fuel data conditions which is time consuming and gives inaccurate readings, inefficiency, fuel economy discrepancy, and accidents. This study aimed to
design and develop an IoT-based fuel monitoring system. The flow meter, ultrasonic level, thermistor fuel temperature,
humidity, and pressure sensors were used to gather fuel information where GSM module was employed to send fuel
data messages to the operator’s phone. An AT mega 328 microcontroller was used to process and analyze the fuel data
and send them to the Thing Speak IoT platform using Wi-Fi connectivity. The results showed that when the fuel level
was less than the threshold value, an operator was alerted by a refilling message via GSM technology. At 0.1Psi
pressure, fuel temperature of 120℃, and 80% humidity, the system notifies the operator by an alert message to check
injector pressure and if the fuel-air mixture was perfect. In addition, these data were observed on LCD and ThingSpeak
webpage. To conclude, the developed system proved the best performance with a 99.98% of success rate with high
accuracy, security, and efficiency rate compared to the current monitoring syste