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Phylogenetic Diversity of Allspice (Pimenta Dioica) Collections from Tanzania Using Chloroplast (Cp) Rbcl Gene
Get PDFThis research article was published in Heliyon journal, 2023This study aims to investigates the phylogenetic relationship between various collection of Allspice (Pimenta dioica) from Tanzania using cprbcL gene as a DNA barcode. Allspice is an important plant species valued for its economic, medicinal, and cultural uses. The morphological similarities between Allspice and other trees in the Myrtaceae family have led to misidentification, making it crucial to use DNA barcoding to study their evolution history. The molecular phylogeny was conducted using DNA extraction, PCR amplification, and sequencing of the rbcL gene, followed by phylogenetic analysis. The genomic DNA was extract using the CTAB method and the rbcL gene amplified with a forward primer 5’-ATGTCACCACAAACAGAGACTAAAGC-3’ and a reverse primer 5’-GTAAAATCAAGTCCACCRCG-3’. Phylogenetic analysis of Allspice rbcL gene was performed by multiple sequence alignment using MUSCLE 5.1 embedded in Geneious Prime software version 2023.0.1 phylogenetic tree was constructed using the same software. The results showed that DNA specimen amplified at amplicon size of average 560bp with GC content of 44%. BLASTN search resulted into more than 96% similarity to seventeen members of Myrtaceae family namely Eucalyptus torquata (NC_022401), Eucalyptus spathulata (NC_022400), Eucalyptus torquata (KC180794), Eucalyptus spathulata (KC180793), Syzygium polyanthum (OQ355361), Syzygium aromaticum (ON920513), Luma apiculata (KX162972), Eugenia aggregata (OP650216), Eugenia Selloi (MN095411), Myrcianthes pungens (MN095409), Campomanesia xanthocarpa (KY392760), Acca sellowiana (KX289887), Syzygium samarangense (NC_060657), Lophomyrtus bullata (MW214669), Lenwebbia prominens (MW214668), Lenwebbia lasioclade (MW214667), and Syzygium nervosum (NC_053907). In the phylogenetic tree Allspice rbcL gene has a close branch to members of Myrtaceae family. This study concludes that there is high genetic diversity among Allspice collection from Tanzania and between member of the Myrtaceae family. Additionally, this study provides a foundation for future research on the evolutionary history and population genetics of Allspice in Tanzania
Investigating the potential of producing eco-friendly liquid biofertilizer from domestic wastewater
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Master’s in Hydrology and Water Resources Engineering of the Nelson Mandela
African Institution of Science and TechnologyWater bodies experience environmental challenges such as eutrophication due to poor
management of domestic wastewater in developing countries. Meanwhile, the explosion in
population of the world has resulted in a 1.8 percent annual increase in demand for fertilizers
that contain important nutrients. Although domestic wastewater contains nutrients (nitrogen,
phosphorus, and potassium) that can be used in agriculture, its recovery is still a challenge.
Some of the potential methods, such as the use of struvite precipitate in recovering nutrients
from wastewater, are not only costly but also introduce a second pollutant into the ecosystem.
The ion exchange method can recover phosphorus from wastewater; however, its
effectiveness is limited by the presence of competing anions, such as sulfates. Freeze
concentration method is one of the potential techniques for recovering nutrients from
wastewater. However, its optimal condition such as temperature and time in recovering
nutrients from domestic wastewater is not well known by researchers. In this study, method
of freeze concentration was studied to establish its optimal condition in recovering nitrate nitrogen and phosphate nutrients from domestic wastewater processed in anaerobic digester.
Frozen liquid and unfrozen concentrated liquid are produced. The effect of freezing
temperature from -10°C to -80°C, freezing time from 1 hour to 8 hours and energy
consumption on the nutrient recovery were investigated. Freezing temperature of -20°C,
cooling time of 7 hours and energy consumption of 0.197 kWh/L resulted in the highest
nitrate-nitrogen and phosphate nutrient recovery value of 1.114 and 4.667 respectively at the
inlet of anaerobic digester 1, 1.325 and 4.975 respectively at the outlet of anaerobic digester
1, 1.099 and 4.859 respectively at the inlet of anaerobic digester 2, 1.132 and 4.755
respectively at the outlet of anaerobic digester 2 and for gravel filter at the outlet the values
where 1.111 and 4.861 respectively. This study shows that, when the freeze concentration
method is used with the right temperature, time, and energy, a significant amount of nutrients
may be recovered from domestic wastewater that can be used as biofertilizer
Prevalence and risk factors for human leptospirosis at a hospital serving a pastoralist community, Endulen, Tanzania
Get PDFThis research article was published in the PLOS Neglected Tropical DiseasesBackground
Leptospirosis is suspected to be a major cause of illness in rural Tanzania associated with close contact with livestock. We sought to determine leptospirosis prevalence, identify infecting Leptospira serogroups, and investigate risk factors for leptospirosis in a rural area of Tanzania where pastoralist animal husbandry practices and sustained livestock contact are common.
Methods
We enrolled participants at Endulen Hospital, Tanzania. Patients with a history of fever within 72 hours, or a tympanic temperature of ≥38.0°C were eligible. Serum samples were collected at presentation and 4–6 weeks later. Sera were tested using microscopic agglutination testing with 20 Leptospira serovars from 17 serogroups. Acute leptospirosis cases were defined by a ≥four-fold rise in antibody titre between acute and convalescent serum samples or a reciprocal titre ≥400 in either sample. Leptospira seropositivity was defined by a single reciprocal antibody titre ≥100 in either sample. We defined the predominant reactive serogroup as that with the highest titre. We explored risk factors for acute leptospirosis and Leptospira seropositivity using logistic regression modelling.
Results
Of 229 participants, 99 (43.2%) were male and the median (range) age was 27 (0, 78) years. Participation in at least one animal husbandry practice was reported by 160 (69.9%). We identified 18 (7.9%) cases of acute leptospirosis, with Djasiman 8 (44.4%) and Australis 7 (38.9%) the most common predominant reactive serogroups. Overall, 69 (30.1%) participants were Leptospira seropositive and the most common predominant reactive serogroups were Icterohaemorrhagiae (n = 20, 29.0%), Djasiman (n = 19, 27.5%), and Australis (n = 17, 24.6%). Milking cattle (OR 6.27, 95% CI 2.24–7.52) was a risk factor for acute leptospirosis, and milking goats (OR 2.35, 95% CI 1.07–5.16) was a risk factor for Leptospira seropositivity.
Conclusions
We identified leptospirosis in approximately one in twelve patients attending hospital with fever from this rural community. Interventions that reduce risks associated with milking livestock may reduce human infections
Quantifying the effects of temperature and predation on the growth of Aedes mosquito population
Get PDFThis research article was published by Springer Nature, 2023Despite having been tested in multiple settings, the quantitative impact of predatory aquatic insects to reduce mosquito population remains unclear. To address this question, an ecological model of Aedes mosquito population incorporating temperature-dependent entomological parameters and predation is developed. The vector reproduction number is derived and entomological parameters that strongly influence it have been identified. Implications of predation on mosquito growth are examined. Results show that predators with high daily attack rate can significantly reduce vector reproduction to extremely low values close to zero. The study provides a framework for more detailed, predator specific studies that are essential to develop an improved understanding on the relationship between predatory aquatic insects and Aedes mosquitoes
Smart system for monitoring and controlling oxygen gas level in high purity germanium detector room: a case study of Tanzania atomic energy commission, Arusha-Tanzania
Get PDFA Project Report Submitted in Partial Fulfilment of the Requirements for the Degree of
Master of Science in Embedded and Mobile Systems of the Nelson Mandela African
Institution of Science and TechnologyLow-oxygen air causes death all around the world. Even though the number of fatalities varies
from year to year and location to location, nitrogen gas replaces oxygen in the atmosphere,
increasing its percentage to less than 21% by volume. Special environment/room such as High
Purity Germanium Detector Room (HPGDR) requires tailored techniques to ensure that oxygen
levels are properly monitored to avoid any hazard. This study was designed for the HPGDR at
Tanzania Atomic Energy Commission (TAEC). The V-Model was used which works well for
small projects with clear requirements. It facilitated each step before moving on to the next level
of development, resulting in the design of an error-free and high-quality system. The ESP32
microcontroller which is built in Wi-Fi was used to send data to the Blynk cloud server. The
developed system is made up of four parts: The sensing component continuously monitors
environmental parameters with Oxygen, MQ-135, and DHT22 sensors. The processing section
processes and analyzes sensor data. The notification component alerts workers via a buzzer and
Short Message Service (SMS). While the controlling component replaces the contaminated
compressed air with fresh air from outside. To provide real-time monitoring, the developed system
employs the Blynk Application. All processed data was accessible via mobile phones using the
Blynk application. The system eliminates both danger and fear because it alerts workers through
SMS and switches on exhaust fan automatically. The HPGDR workers and the administrators are
the main beneficiaries of the developed system
Diversity of Ralstonia solanacearum Causing Tomato Bacterial Wilt Disease in Tanzania
Get PDFA research article was published by International Journal of Plant Pathology Year: 2023 | Volume: 14Background and Objective: Ralstonia solanacearum (Smith) is one of the most destructive bacterial plant pathogens in the world. It causes bacterial wilt disease (BWD) in several plant species including tomato. This research was carried out to understand the diversity of the causing bacterial isolates and develop management strategies based on the characteristics of the prevailing pathogens in Tanzania. Materials and Methods: Forty isolates were collected from the infected tomato plants preserved in the laboratory from the BWD field survey in 2018 in Tanzania. Isolates were grown on TTC medium and DNA was extracted from a single colony of each isolate using the bacterial DNA extraction kit for molecular analysis using PCR. The similarity coefficients were predicted by the Dice technique for all possible isolate pairs based on the fingerprint groups. Finally, the aligned sequences were contrasted with the standard strains in the National Center for Biotechnology Information (NCBI) database to determine resemblance using the Basic Local Alignment Tool (BLAST). Results: According to the results of the phylogenetic analysis, 80% of the samples belonged to phylotypes I and III of the R. pseudosolanacearum and 20% to phylotype II of the R. solanacearum genospecies, respectively. Findings have shown that Tanzania has a diversified population of the Ralstonia solanacearum species complex that causes tomato BWD. Two species and three phylotypes of infections that cause tomato BWD were found to predominate in various agro-ecological zones across the nation. Phylotypes I and III of Ralstonia pseudosolanacearum and phylotype II of Ralstonia solanacearum were the isolates that were found. Conclusion: Strong standard phytosanitary measures must be implemented worldwide by plant health authorities as a result of the first report of phylotype II of RSSC in Tanzania.Background and Objective: Ralstonia solanacearum (Smith) is one of the most destructive bacterial plant pathogens in the world. It causes bacterial wilt disease (BWD) in several plant species including tomato. This research was carried out to understand the diversity of the causing bacterial isolates and develop management strategies based on the characteristics of the prevailing pathogens in Tanzania. Materials and Methods: Forty isolates were collected from the infected tomato plants preserved in the laboratory from the BWD field survey in 2018 in Tanzania. Isolates were grown on TTC medium and DNA was extracted from a single colony of each isolate using the bacterial DNA extraction kit for molecular analysis using PCR. The similarity coefficients were predicted by the Dice technique for all possible isolate pairs based on the fingerprint groups. Finally, the aligned sequences were contrasted with the standard strains in the National Center for Biotechnology Information (NCBI) database to determine resemblance using the Basic Local Alignment Tool (BLAST). Results: According to the results of the phylogenetic analysis, 80% of the samples belonged to phylotypes I and III of the R. pseudosolanacearum and 20% to phylotype II of the R. solanacearum genospecies, respectively. Findings have shown that Tanzania has a diversified population of the Ralstonia solanacearum species complex that causes tomato BWD. Two species and three phylotypes of infections that cause tomato BWD were found to predominate in various agro-ecological zones across the nation. Phylotypes I and III of Ralstonia pseudosolanacearum and phylotype II of Ralstonia solanacearum were the isolates that were found. Conclusion: Strong standard phytosanitary measures must be implemented worldwide by plant health authorities as a result of the first report of phylotype II of RSSC in Tanzania
The hydrochemical evolution and water balance of the emakat lake in the northern crater highland of Tanzania
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Master’s in Hydrology and Water Resources Engineering of the Nelson Mandela African Institution of Science and TechnologyThis study aimed to ascertain the hydrochemical evolution and water balance of Emakat Lake,
of the Empakaai Crater. Water and rock samples were collected from the lake and springs on
the inner and outer crater rims, and at the foot of the Empakaai Crater. The results showed that
the lake is a highly alkaline (pH > 10) and saline (electrical conductivity (EC) = 28,860 - 29,460
μs/cm) with the concentration of total dissolved solids (TDS) ranging from14,432 to 14723
mg/L. Springs exhibited lower pH (6.85 - 8.69), EC (562 - 1584 μs/cm) and TDS (276 - 1016
mg/L). The dominant ions in Emakat Lake were Na+
and CO3
2-+HCO3
- which occupy about
80% and 85% of the cation and anion phases with ion distribution of Na+ > K+ > Ca2+ > Mg2+
and (CO3
2- + HCO3
-
) > Cl- >SO4
2- > F- > NO3- > PO4
3-
. Piper, chloro-alkaline indices, Chadha,
and Gibbs plots revealed that Na-K-HCO3 water type dominated Emakat Lake, and a majority
of springs exhibited mixing characteristic water type. Base ion-exchange dominated the
hydrochemical evolution of both lake and springs, influenced by evaporation and water-rock
interaction for the lake and springs respectively. The water balance of Emakat Lake was highly
influenced by groundwater flow which accounted for 49% of the inflow and 56% of the
outflow. This suggest that Emakat Lake plays a major role in the hydrological system in the
area alongside the springs which are the sources of the major rivers of Engaruka and
Engaresero
Tuning water chemistry for the recovery of greener products: pragmatic and sustainable approaches
Get PDFThis research article was published on 17 February,2023 and its available on nm-aist institutional repositoryThe early techniques for recovery of bioactive metabolites
involve conventional cold or hot solvent extraction.1 The choice
is a function of the nature of the bioactive compound of
interest.2 The adverse effect of organic solvents (Table 1) which
are mostly preferred extraction techniques has warranted the
search for greener alternatives. One of the ways green extrac tions is described involves the isolation of medicinally active
portions from a bio-material,3 with the simultaneous use of eco friendly solvents and optimal use of energy.4–9 Prospecting for
green solvents has brought water to the fore of extraction
technology.10 Water is affirmatively described as the “greenest
solvent” imaginable, with its availability at the required purity,
it is cost-effective, readily recycled, non-toxic, non-ammable,
and eco-friendly.10–13 Based on the green chemistry precept,
water is considered a green chemical per excellence.14–16 Water
is useful in the recovery of various phytochemicals including
alcohols, sugars, proteins, and organic acids with natural water soluble properties.12,16–21 However, water as a solvent has some
physical and chemical property disadvantages when compared
to organic solvent.21–23 The polar nature of water in its natural
form reduces its efficacy and acceptability when compared with
organic solvents for some kinds of extractions. Organic solvents
are extensively desirable since they exhibit better recovery than
water at ambient conditions.3 Further setbacks experienced
when using conventional hydro-extraction include time and
energy consumption, thermal decomposition of thermo sensitive metabolites and low recovery of hydro-solvent in its
natural form.
There exists the need to investigate water properties that can
be improved to complement its natural advantage and eradicate
its attendant limitations as a solvent for extraction.5,8,10,28,29 have
indicated that improving traditional extraction must entail
decreased energy input, sustainability and a non-toxic nal
product. Improving water to own variable chemistry will aid the
extraction of a broad range of polar and non-polar biomolecules
from sustainable natural products with non-toxic quality and
eco-friendliness.10,21,29 This approach will prevent the use of
organic solvents, fossil energy, chemical waste and risks of
extraction. It is known that water existing in its tunable form
satises the conditions of green solvents.11–13 Recently, th
Designing a novel method for brain volume quantification in investigating childhood brain atrophy and its functional effects
Get PDFA Thesis submitted in fulfillment of the requirements for the award of the Degree of Doctor
of Philosophy in Life Sciences of the Nelson Mandela African Institution of Science and
TechnologyBrain atrophy is a result of volume loss commonly indicated by brain parenchyma separation
from calvarium on neuroimaging. The prevalence of childhood brain atrophy has not been
determined globally. Despite sporadic reports, surprisingly little is known about the prevalence,
risk factors, and functional effects, except in children's brains associated with epilepsy. There is
currently no published alternative to high-priced automated technologies for reproducible manual
quantification of brain volume. The primary aim of the study was to develop a manual diagonal
brain fraction (DBF) formula for quantifying and grading brain volume to evaluate the effects of
brain atrophy among children in the selected East African Countries-Northern Tanzania and
Rwanda. Children in Northern Tanzania and Rwanda were analysed for evidence of brain atrophy
using one-dimension linear radiological techniques and a newly developed formula, revealing a
prevalence of 14.06% and 22% respectively. There were four distinct grades of disease severity.
Head trauma, neonatal hypoxia, central nervous system infections, and increased intracranial
pressure were cited as potential inducers of the atrophy. Significant alterations in brain waves were
observed using EEG, which proved the altered functional implications of brain atrophy. These
included, for example, decreased Delta/Alpha ratios (DAR) and higher beta activity. There is a
negative relation between brain volume and IQ test scores in atrophied brain. Brain atrophy was
also found to be strongly related to the presence of convulsive disorders. The results of this study
conclude that, childhood brain atrophy is quite widespread among the population that was studied.
The DBF is a straightforward technique for evaluating overall brain volume. Possible risks of brain
atrophy in children include birth injury, central nervous system infection, head trauma and
increased intracranial pressure. Beta activities such as Beta/Alpha ratio (BAR) may serve as brain
atrophy bio-markers while the Delta/Alpha ratio (DAR) is trivial in brain atrophy settings. Damage
to the brain's neurocognitive functions is reflected by lower-than-average IQ percentile score for
age in atrophied brains. As a result, it is critical to develop methods of protecting children's mental
health from potential risks
Capacity building to strengthen nuclear security in the safety, operation and utilization of research reactors in Africa
Get PDFThis Research Article was published by the Arab Journal of Nuclear Sciences and ApplicationsResearch reactors are indispensable for developing countries to benefit from the many quiet applications of nuclear science and technology, particularly in health services, food security, water resources, education and training and the development of nuclear technology. However, only eleven of the world's 220 operational research reactors are operational on the African continent. This means that only 3% of the world's nuclear research reactor capacity has access to 17.2% of the world's population in Africa. In this regard, there is a major gap in the nuclear power sector in Africa that needs to be filled for the economic development of developing countries, including the advent of micro and small modular reactors. Since research reactors encompass a wide range of facilities that involve different aspects and security considerations compared to other facilities in the nuclear industry, the nuclear security culture for personnel who work or are expected to work in nuclear reactors is essential for compliance with nuclear safety requirements. In this context, capacity building in the areas of security, operation and use of research reactors is important in order to strengthen the nuclear safety of this installation in developing countries. This paper addresses the need for human resource capacity building in Africa, particularly in Tanzania