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Accumulation and bioconcentration of heavy metals in two phases from agricultural soil to plants in Usangu agroecosystem-Tanzania
Get PDFThis research article was published by Heliyon, 2021The build-up of heavy metals (HM) in agricultural soils accelerates the HM uptake by plants, which could potentially affect food quality and food safety. Here we studied the status and bioaccumulation of HM from soils to plant parts (roots, stem, and grains) in Usangu agro-ecosystem-Tanzania. In total 68 soil samples and 42 rice plant samples from six irrigation schemes were studied. The concentrations of cadmium-Cd, chromium-Cr, copper-Cu, lead-Pb, zinc-Zn, nickel-Ni, and iron-Fe were determined to estimate accumulation, distribution, bioconcentration. Total soil HM concentration in soil and plant samples was determined by acid digestion. The concentration of HM in soils samples (in mg/kg) were Cr (4.58–42.76), Co (1.486–6.12), Fe (3513.56–12593.99), Zn (7.89–29.17), Cd (0.008–0.073), Cu (0.84–9.25), Ni (0.92–7.98), and Pb (1.82–18.86). The total HM concentration in plant samples were (in mg/kg) were Cu (5.18–33.56), Zn (57.03–120.88), Fe (963.51–27918.95), Mn (613.15–2280.98), Cd (4.3–17.46), Pb (0.01–28.25), Cr (12.88–57.34) and Ni (9.65–103.33). The concentration of HM in soil and plant parts was observed to vary among locations where high concentrations of HM were detected in stems and roots compared to grains. The ratio HM in plants and soil samples (bioconcentration) was higher than one for some sites indicating higher HM uptakes by plants leading to possible health risk to soil invertebrates, animals, and humans. The bioconcentration factor varied among schemes, with the highest values at Igalako and Mahongole, which could be caused by artisanal gold mining and mining quarry existed in the area. Therefore, steps are needed to reverse the situation to balance the HM in agricultural soils and plant tissues to be within acceptable limits.
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Design of a Passenger Security and Safety System for the Kayoola EVs Bus
Get PDFThis research article was published by IEEE, 2021Kiira Motors Corporation seeks to avail customer satisfaction, by providing noteworthy passenger experience on its market entry product, the Kayoola EVs bus through deploying a passenger security and safety system to curtail rampant snags like passenger insecurity, loss of passenger property, shortcomings in management and accountability as well as the spread of contagious sicknesses like COVID-19 which are not alien occurrences on commuter taxis and buses in African cities. On this project, a comprehensive system was designed for remote CCTV video surveillance, video analysis for people detection, passenger count and social distance analysis, as well as digital contact tracing to solve the challenges. It denotes significant potential to improve the security of property and passengers, shrink the risk of the spread of contagious diseases, enable timely capture of contact tracing records and lessen the burden of management, monitoring and accountability for the numbers of passengers on buses for fleet owners
Effectiveness of management (coping) strategies for Chromolaena odorata by smallholder farmers in Serengeti District, Tanzania
Get PDFThis research article was published by INNSpub, 2021The study aimed to assess the performance of farmer-led production practices adopted in maize farming systems to recommend the best adoption methods for coping with Chromolaena odorata, one of the world’s deadliest invasive alien species (IAS). The study also aims to make this adaptive strategy available so that smallholder farmers can readily use it to make better decisions on the effective use of land infested with this IAS for crop production, particularly in the Serengeti area, where communities are already experiencing a strong establishment and spread of this and other IAS.Field experiment was conducted in Serengeti District to test if the local community’s management practice for managing Chromolaena odorata as one of the major invasive species dominated the area is cost-effectively and can be adopted for the management of this invasive. The experiment was laid out. The setting up of the Chromolaena odorata management (weeding) plots in the trial sites of this study were done in six different weeding categories. These categories were based on informed management practices conducted by local communities in the Serengeti District as strategies for dealing with Chromolaena odorata infestation in their cultivated land. Weeding levels were used to test which management practice perform well in agricultural field with Chromolaena odorata. One way Analysis of Variance (ANOVA) was used to assess for the significant variation between treatments. The finding indicate that In treatment where Chromolaena odorata was managed well there was an increase of yield compared to the treatment with less management. Such adaptation is a crucial component of securing the invaded crop areas’ future food production in the face of global environmental change. These results should inform relevant sectors, and stakeholders of this important initiative and encourage collaboration for implementation in affected areas
Building Climate Change Adaptation and Resilience through Soil Organic Carbon Restoration in Sub-Saharan Rural Communities: Challenges and Opportunities
Get PDFThis research article was published by MDPI, 2021Soil organic carbon (SOC) is widely recognised as pivotal in soil function, exerting important controls on soil structure, moisture retention, nutrient cycling and biodiversity, which in turn underpins a range of provisioning, supporting and regulatory ecosystem services. SOC stocks in sub-Saharan Africa (SSA) are threatened by changes in land practice and climatic factors, which destabilises the soil system and resilience to continued climate change. Here, we provide a review of the role of SOC in overall soil health and the challenges and opportunities associated with maintaining and building SOC stocks in SSA. As an exemplar national case, we focus on Tanzania where we provide context under research for the “Jali Ardhi” (Care for the Land) Project. The review details (i) the role of SOC in soil systems; (ii) sustainable land management (SLM) techniques for maintaining and building SOC; (iii) barriers (environmental, economic and social) to SLM implementation; and (iv) opportunities for overcoming barriers to SLM adoption. We provide evidence for the importance of site-specific characterisation of the biophysicochemical and socio-economic context for effective climate adaptation. In particular, we highlight the importance of SOC pools for soil function and the need for practitioners to consider the type of biomass returns to the soil to achieve healthy, balanced systems. In line with the need for local-scale site characterisation we discuss the use of established survey protocols alongside opportunities to complement these with recent technologies, such as rapid in situ scanning tools and aerial surveys. We discuss how these tools can be used to improve soil health assessments and develop critical understanding of landscape connectivity and the management of shared resources under co-design strategie
Prevalence and histopathological characterization of Masai Giraffe (Giraffa camelopardalis tippelskirchi) skin disease in Tarangire-Manyara ecosystem, Northern Tanzania
Get PDFThis research article was published by Taylor & Francis online, 2021Background: Masai Giraffes have declined dramatically in recent decades due to loss of
habitat and illegal hunting. Hence, it is critically important that the epidemiology and eti ology of so-called giraffe skin disease (GSD) is understood well.
Aim: To assess the prevalence and histopathological characteristics of GSD in the Tarangire Manyara Ecosystem (TME), northern Tanzania.
Methods: The study used road transects to gather field information on GSD. Eighty-four
giraffes were sighted by systematic random sampling in the six study sites. Examination of
giraffes involved body distribution of lesions, severity of the lesions and whether they were
associated with age and sex of the affected giraffes. Five giraffes with GSD were immobilized
for tissue collection and histopathological analysis.
Results: Prevalence among adults was 79%. Affected animals typically had 1–5 lesions which
were mostly moderate and were predominantly observed on the forelegs. GSD positivity
rate was higher among females versus males, whereas males had a higher rate of severe
lesions and generally had more lesions than females. Calves showed no lesions. All tissue
sections from five affected giraffes showed the presence of large quantities of fungal ele ments (hyphae and spores) that involved hair shafts and sub-cutaneous tissue after staining
with Grocott Methenamine Silver as special fungal staining technique.
Conclusions: Our findings suggest the involvement of fungal infection in GSD pathogenesis.
Clinical relevance: We recommend further characterization of the lesions using modern
molecular techniques and culture to identify primary and secondary or opportunistic etiolo gies, and the order in which the pathogens occur in the lesions
Mathematical models of trypanosoma brucei rhodesiense disease transmission and control strategies
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of
Doctor of Philosophy in Mathematical and Computer Sciences and Engineering of the
Nelson Mandela African Institution of Science and TechnologyHuman African Trypanosomiasis (HAT), also known as sleeping sickness is a neglected dis ease that impacts 70 million people living in 1.55 million km2
in sub-Saharan Africa. The
disease strikes predominantly poor populations in sub-Saharan Africa and has been targeted
for elimination as a public health problem by 2030. Despite decades of control operations, the
disease remains enigmatic and persists in populations at low levels of prevalence. Hence sev eral research approaches must be utilized to infer on the feasibility of attaining the set target.
Among them, mathematical modeling is a very successful tool and has been extensively used
for different diseases.
In this study four mathematical models were proposed to evaluate the effects of educational
campaigns, seasonality, memory effects, time delay and heterogeneity in the human population
on Trypanosoma brucei rhodesiense transmission and control dynamics. In the formulated
models the basic reproduction number R0 was computed and qualitatively used to establish the
condition for disease eradication and persistence. In the first model, effects of human awareness
through educational campaigns and use of insecticides on short-and long-term dynamics of the
disease were evaluated. Analytical results of the study showed that the model undergoes a
backward bifurcation.
Further, upon extending the model to incorporate time-dependent educational campaigns and
the use of insecticides, it was noted that when the aforementioned strategies were intensified
the associated costs were also high, and the reverse was true. Moreover, it was also noted that
reducing the upper bound of educational campaign control (u1) from 1 to 0.5 and insecticide
control (u2) from 1 to 0.3 could lead to a 17.6% reduction in costs.
Next, the model system was extended to include temperature and case detection followed by
treatment of infected humans. With the aid of suitable Lyapunov functionals, the global stability
of the model’s steady states was carried out. Upon simulating the model with temperature
fixed at 20 and 25◦C, it was noted that the value of vector control be greater than 30 and 50%
respectively for R0 to be less than unity. Lastly, the time delay factor was included in the model
system to assess the effects of incubation period on the dynamics of T. brucei rhodesiense
disease in the population. The numerical results demonstrated that the inclusion of the time
delay factor in the model system destabilized the endemic equilibrium point leading to Hopf
bifurcation
A Review of Usage and Applications of Social Media Analytics
Get PDFThis research article published by Veritas Publications LTD, 2021This paper presents the report of a social media analytics (SMA) review. The review conducted to find out the methods and tools used in social media analytics, types of social media platforms which the SMA are performed and the field which SMA has been performed. Social media contains a lot of user uploaded data in different formats like text, images, photos, video etc. These large volumes of data are converted in meaningful information which can be understood using different methods and tools which are called social media analytics. A literature review of articles published between 2010-2020 has been conducted using articles obtained from reputable databases IEEE Xplore, ACM digital, Emerald insight, Springer Link and Science direct. A number of 44 articles have been selected for review from 110 retrieved papers. The paper has been reviewed according to the study objectives. The study found that SMA tools and techniques which have been used are sentiment analysis, youtube analytics, visible intelligence, IBM Watson tool and predictive models. The social media platforms which were mostly used are twitter, facebook, youtube, trip advisor and blogs. SMA has been observed in different fields like agriculture, politics, health, social and business sector
Abrogating the nsp10–nsp16 switching mechanisms in SARS-CoV-2 by phytochemicals from Withania somnifera: a molecular dynamics study
Get PDFThis research article published by Taylor & Francis Online, 2021The search for therapeutic small molecules and vaccines for Covid-19 treatment is an urgent but evolving topic. The virus has claimed over 3,782,490 lives (as of 12 June 2021), with the figure expected to rise due to the high versatility of the SAR-CoV-2 variant. Therapeutic options based on SARS-CoV-2 inhibitor are essential. Withanolides have a long history in traditional medicines with versatile biological properties including antiviral activities. In this study, the inhibitory potential of withanolides from Withania somnifera (Ashwagandha) against SARS-CoV-2 non-structural protein 10 (nsp10) was investigated by employing atomistic in silico methods viz molecular docking, molecular dynamics and binding free energy calculations. Investigated Withania somnifera compounds demonstrated binding affinity to the nsp10 and in its complex form, that is, nsp10-nsp16 heterodimer. Two withanolides; withanoside IV and withanoside V isolated from the roots of Withania somnifera demonstrated strong inhibition with binding free energies of −29.5 and −29.1 kJ/mol, respectively. Molecular dynamics and binding free energy ascertained the stability of withanoside IV. Water molecules, although known to play an important role in mediating biological systems, herein, water was found to have a repulsive binding effect to some residues, suggesting that the binding of withanoside IV would require dewetting of the nsp10 or displacing the water to bulk solvents. Interestingly, residues in the nsp10 that are responsible for forming stable interaction at the nsp10–nsp16 were found to be strongly interacting with withanoside IV, hence weakening the nsp10–nsp16 interaction and recognition. Further in vitro and in vivo experiments are recommended to validate the anti-SARS-COV-2 potential of these phytochemicals
A novel framework for the use of mobile applications in inducing smallholder-farmers’ response to farming as a business via benchmarking
Get PDFA Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor
of Philosophy in Information and Communication Science and Engineering of the
Nelson Mandela African Institution of Science and TechnologyFarming as a business (FAAB) is currently acknowledged as the best route out of poverty for
the majority of rural poor farmers in developing countries like Tanzania. Supporting farmers
to participate in FAAB translates into assisting them to go through a farming life cycle of
five interrelated stages namely: Agricultural domains recognition, farm characterization,
simulation of predictive solutions, identification of limiting factors, and post production
evaluation. Managing FAAB processes, resources and products, requires benchmarking as its
analytical tool; hence, the concept of farming as a business via benchmarking (FAABB).
Supporting a farmer to achieve FAABB is the primary role of an Extension Officer (EO).
Since FAABB is a data-intensive activity, computational and cognitive limitations of an EO
decrease quality and efficiency and increase time spent as well as costs related to facilitating
smallholder farmers to achieve FAABB. Several research efforts have demonstrated that
mobile apps bring in significant capabilities for helping EOs deal with the
challenges associated with FAABB.
However, in Tanzania, data capture and codification are the two greater obstacles in
developing useful mobile applications, than gaps in conceptual theories or available methods
for FAABB. This research takes advantage of available technologies to develop a mobile
framework for FAABB that embeds data capture and codification services to support rapid
development of domain specific m-apps. The main objective of this research is, therefore, to
develop a mobile framework for FAABB (m-FFAABB) that facilitates knowledge capture
and codification for rapid development and use of m-apps that induce farmers‟ response to
FAABB.
The research adopted a Design Science Research (DSR) through Soft System Methodology
(SSM). In the reported work, the framework was designed and two corresponding prototypes
were developed and evaluated to show the applicability of m-FFAABB. The data collected
during the experiments show that the mobile apps developed through the m-FFAABB
are useful, well integrated and easy to use. Moreover, statistical analysis of the
results indicates that the framework reduces time, costs, and intellectual effort of the EOs
A Secure and Efficient Multi-Factor Authentication Algorithm for Mobile Money Applications
Get PDFThis research article published by MDPI, 2021With the expansion of smartphone and financial technologies (FinTech), mobile money emerged to improve financial inclusion in many developing nations. The majority of the mobile money schemes used in these nations implement two-factor authentication (2FA) as the only means of verifying mobile money users. These 2FA schemes are vulnerable to numerous security attacks because they only use a personal identification number (PIN) and subscriber identity module (SIM). This study aims to develop a secure and efficient multi-factor authentication algorithm for mobile money applications. It uses a novel approach combining PIN, a one-time password (OTP), and a biometric fingerprint to enforce extra security during mobile money authentication. It also uses a biometric fingerprint and quick response (QR) code to confirm mobile money withdrawal. The security of the PIN and OTP is enforced by using secure hashing algorithm-256 (SHA-256), a biometric fingerprint by Fast IDentity Online (FIDO) that uses a standard public key cryptography technique (RSA), and Fernet encryption to secure a QR code and the records in the databases. The evolutionary prototyping model was adopted when developing the native mobile money application prototypes to prove that the algorithm is feasible and provides a higher degree of security. The developed applications were tested, and a detailed security analysis was conducted. The results show that the proposed algorithm is secure, efficient, and highly effective against the various threat models. It also offers secure and efficient authentication and ensures data confidentiality, integrity, non-repudiation, user anonymity, and privacy. The performance analysis indicates that it achieves better overall performance compared with the existing mobile money systems