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Impact of tobacco curing on the environment andsocio-economic aspects in the Urambo District
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Master’s in Environmental Science and Engineering of the Nelson Mandela African
Institution of Science and TechnologyDespite the efforts that have been employed to reduce tobacco curing related deforestation in
many countries including Tanzania. The economic importance of tobacco production on
employment creation and foreign exchange makes production continue to increase which
increases the demand for wood fuel that results in deforestation. This study assessed the impact
of the tobacco curing process on the environment and socio-economic aspects. This was
achieved through a structured questionnaire and Specific Fuel Consumption (SFC)
assessments. A cross-sectional study design was adopted whereby structured questionnaires
were administered to 892 respondents who are tobacco farmers from nine Primary Tobacco
Farmer Cooperatives in the Urambo district. Structured questionnaires’ data were analyzed
using Microsoft Excel to determine the Cost-Benefit Analysis then subjected to SPSS for
descriptive statistics. In addition, SFC data were employed to estimate annual woodland area
cleared, carbon emission, and carbon dioxide hindered from sequestration. The results show
that 95% of all tobacco farmers have been harvesting wood fuel from forest woodland. This
caused tobacco related-deforestation of 6355.47 ha in 2018/19 that hindered 6 3554.73 tons of
atmospheric carbon dioxide from sequestration. Also, the emission of 3 3366.24 tons of carbon
dioxide was recorded during the curing process. Rocket barn version 2 (RB2) and traditional
barn (TB) were observed to have higher net revenue compared to rocket barn version 3 (RB3)
and standard barn (SB). For this reason, rocket barn and traditional barn are more preferred
than rocket barn and standard barn. The findings also revealed the social aspects associated
with tobacco curing including labor intensity and food insecurity. Based on these findings, it
is recommended that to improve the sustainability of tobacco farming, alternative and
affordable tobacco curing technologies should be instantly developed to replace wood fuel that
poses problems of environmental degradation
Nutritional and functional values of microalgae (spirulina) naturally found in East Africa
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Doctor of Philosophy in Life Sciences of the Nelson Mandela African Institution of
Science and TechnologySub-Saharan Africa has a higher prevalence of undernutrition, which is the underlying cause
of stunting and underweight problems in children. Undernutrition is generally caused by
insufficient intake of nutrients; in Africa, it’s mainly due to over-reliance on plant-based staple
diets which contain inadequate amount of essential nutrients. Spirulina is a naturally abundant
microalgae with great nutritional values and could be utilized to fortify diets to enhance human
health. Therefore, this study evaluated nutrient content, bioavailability and safety of locally
found Spirulina products, focusing specifically in East Africa, to enable possible food-based
strategic interventions aimed at improving human nutrition in the region. A field survey was
conducted to identify local Spirulina producers in East Africa and obtain samples. A total of
54 mice were used in evaluating the nutrient bioavailability and safety in vivo. A randomized
control trial research design was used to select and allocate mice into treatment groups.
Randomly grouped mice were separately fed three diets: control (basal), test (15% Spirulina
powder blended with 85% basal diet) and standard (basal diet supplemented with standard
nutritional supplements). The test and standard diets had equivalent nutrient content to enable
direct comparison of results. Nutrients content analyses showed that a 100 g analyzed Spirulina
samples contains 70 g protein, 82 mg iron, 84.5 mg zinc, 1302 mg calcium, 628 mg
phosphorous, 27 g vitamin A, 246.8 g vitamin B9, 3.99g vitamin B12, 1.92 mg QE/g total
flavonoid and 2.99 mg GAE/g total phenolic. The nutrients bioavailability from the control diet
was statistically lower than those of test and standard diets, whose results were comparable.
After the feeding experiment, mice had no significant differences in their serum aspartate
aminotransferase (AST), alanine aminotransferase (ALT), cystatin C and troponin I
concentrations, indicating that the studied concentrations of control, test and standard diets had
no adverse effect on critical organs (liver, heart, or kidney) of the mice. These results indicate
the safety of Spirulina and reinforce its importance in reducing undernutrition in humans
Performance of inclined plates settler integrated with constructed wetland for high turbidity water treatment
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Masters in Hydrology and Water Resources Engineering of the Nelson Mandela African
Institution of Science and TechnologyThe purpose of this study was to investigate and demonstrate a cost-effective treatment
technology for high turbid water, commonly used for domestic purposes in rural areas of
Tanzania where conventional water treatment techniques are not available. A study was
conducted on the water quality status of five permanent earth dams within Monduli district
during the wet and dry seasons, by analyzing physicochemical and microbial characteristics.
The water characteristics of the five earth dams tested were significantly correlated (p < 0.05)
and most of the tested parameters including turbidity and faecal coliform (FC) were above the
Tanzania Bureau of Standards (TBS) drinking water standards. In this study, a pilot-scale
inclined plates settler integrated with constructed wetland (IPS-CW system was tested on
Nadosoito dam water with turbidities ranging from 186 to 4011 NTU. The IPS-CW system
was meant to remove organic matter, nutrients and pathogens, with major focus on turbidity
and FC removal, at the test flow rates of 20, 15, 10 and 5 L/min. The system removed
substantial amount of contaminants, thereby achieving maximum removal efficiency of
95.9% and 94.3% for turbidity and FC respectively. Although using this combination of
technologies in improving drinking water quality is uncommon, nitrate
and biochemical
oxygen demand met the TBS and World health Organization drinking water standards of ≤ 50
mg/l and ≤ 6 mg/L respectively. Due to low production cost and simplicity in operation, the
system can be implemented in rural communities with high turbidity water sources however,
further disinfection is required to ensure zero FC
The Importance of Educating Girls and Women in Sciences
Get PDFThis book chapter published by University of Technology Sydney ePress, 2021For the past decades, focus on attaining gender equality in science education has attracted
a lot of attention. Governments and international community believe that girls’/women’s
science education is a worthwhile investment; it has many direct effects on economic
growth and human welfare. In this chapter, we discuss this view as a tool for development
as well as the moral aspect of creating equality. We focus on what practically is being done
to promote girls’/women’s science education and why their participation continues to be
low despite many efforts and heavy investmen
Controlling ammonia and sulfide inhibition during anaerobic digestion of slaughterhouse waste
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Philosophy in Materials Science and Engineering of the Nelson Mandela African
Institution of Science and TechnologyThe performance of experimental batch-reactor loaded with slaughterhouse waste at mesophilic
temperature was investigated as well as the inhibition of both ammonia and sulfide in the
aqueous phase during phase I of anaerobic digestion. The methylene blue method was used to
quantify the amount of sulfide in the liquid phase whereby the amount of total ammonia
nitrogen in the liquid phase was quantified by using Nessler method. The maximum CH
4
content of 69.6% was achieved at 0.37 VFA/Alkalinity ratio and pH of 7.51 during day 37 of
anaerobic digestion. However, a sudden increase of ammonia nitrogen in the digester from day
44 to day 68 decreased the methane content by 62.15% from 65% to 24.6%. During phase II of
anaerobic digestion, the efficacy of inorganic additives on the removal of total ammonia
nitrogen and sulfide in the aqueous phase of slaughterhouse waste undergoing anaerobic
digestion in the batch reactor was investigated for 65 days. A mixture of natural inorganic
additives processed from the anthill and red rock soil samples collected from Arusha, Tanzania
were used as adsorbents in different ratios. XRD analysis revealed that the anthill soil sample is
endowed with quartz and hematite major mineral phases while red rock soil contains albite,
pyroxene, and quartz as predominant phases. The anthill and red rock soil samples calcined at
900 ℃ displayed higher BET surface areas of 815. 35 and 852.35 m
2
/g, respectively. Among
all the adsorbent ratios investigated at different calcination temperatures, the ratio of 1:1 and
calcination temperature of 700℃ produced the highest adsorption capacities of both TAN and
sulfide. Adsorption isotherm studies revealed that Jovanovich model fitted better to the
experimental data than Langmuir and Freundlich models. The findings of this study have
demonstrated that anthill and red rock soils can be exploited as affordable, ecofriendly and
efficient adsorbents for mitigation of TAN and sulfide from the liquid phase and sustenance of
methanogenesis
Modeling the Effect of Binding Kinetics in Spatial Drug Distribution in the Brain
Get PDFThis research article published by Hindawi, 2021A 3-dimensional mathematical model is developed to determine the effect of drug binding kinetics on the spatial distribution of a
drug within the brain. The key components, namely, transport across the blood-brain barrier (BBB), drug distribution in the brain
extracellular fluid (ECF), and drug binding kinetics are coupled with the bidirectional bulk flow of the brain ECF to enhance the
visualization of drug concentration in the brain. The model is developed based on the cubical volume of a brain unit, which is a
union of three subdomains: the brain ECF, the BBB, and the blood plasma. The model is a set of partial differential equations
and the associated initial and boundary conditions through which the drug distribution process in the mentioned subdomains is
described. Effects of drug binding kinetics are investigated by varying the binding parameter values for both nonspecific and
specific binding sites. All variations of binding parameter values are discussed, and the results show the improved visualization
of the effect of binding kinetics in the drug distribution within the brain. For more realistic visualization, we suggest
incorporating more brain components that make up the large volume of the brain tissue
Development of self-monitoring mobile system for diabetes management in adult population of Tanzania
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Master of Science in Embedded and Mobile Systems of the Nelson Mandela African
Institution of Science and TechnologyDiabetes is a chronic disease that affects millions of people globally and the number alarmingly
increases annually. Since it results in an excessive amount of glucose in the blood, if not well
managed and controlled, diabetes can cause severe complications such as cardiovascular and
renal issues, blindness and nerve damage. Apart from the medication and injections that
patients get from their health centers to control it, the biggest responsibility falls on the patient
themselves to take the medication, eat proper diet, maintain good weight and regularly exercise
to manage the illness. It is for this reason that this mobile platform is developed. DiabAssistant
is a mobile and web app developed using Flutter and Django respectively with an API to bridge
the two. This supportive platform helps diabetic patients be able to follow the trends of their
glucose levels, get suggestions of possible reasons for the spikes based on the data they entered
as well as get recommendations of what to do next to lower the glucose level. They can also
choose to share with their doctor the reports generated from the app to better help the doctors
come up with a more efficient treatment plan based on real data from the patient. Patients and
endocrinologists were involved in different stages of the project to capture what a Tanzanian
diabetic patient needs and the most user-friendly way to deliver those needs. The platform was
found useful among diabetic patient as well as their doctors since it served as an assistant in
aiding in the control and management of the disease
Illegal harvesting threatens fruit production and seedling recruitment of Balanites aegyptiaca in Dinder Biosphere Reserve, Sudan
Get PDFThis research article published by Elsevier, 2021Illegal harvesting negatively affects the forest tree populations, particularly in sub-Saharan Africa, but little is known how fruit production and seedling recruitment are impacted. We assessed recruitment parameters of Balanites aegyptiaca trees in the Dinder Biosphere Reserve (DBR) across 100 sample plots of 25 m x 40 m in both human-impacted (disturbed) and undisturbed sites. We found that the average number of fruiting branches of B. aegyptiaca in the undisturbed sites were three times as high as those in the disturbed sites (F1,98 = 139, P < 0.001). Further, fruiting branches were positively correlated with crown width (R2 = 0.71, β = 7.1, P = 0.01) across both sites. The height and crown width of B. aegyptiaca in the undisturbed sites were double that of the disturbed sites (F1,196 = 80, P < 0.001; F1,196 = 94.8, P < 0.001). Saplings and seedlings at the undisturbed sites were three times and twice that of the disturbed sites, respectively (F1,196 = 94.5, P < 0.001; F1,196 = 100.8, P < 0.001), with a positive correlation to the average number of fruiting branches (R2 = 0.74, β = 0.45, P < 0.001). The soil nitrogen and phosphorus contents beneath trees in the undisturbed sites were almost double that of those in the disturbed sites (F1, 196 = 68.1, P < 0.001; F1, 196 = 97.9, P < 0.001) while sodium and electrical conductivity were by about 50% lower (F1, 196 = 535.8, P < 0.001; F1, 196 = 16.1, P < 0.001). We conclude that illegal harvesting in DBR severely reduced tree structure and recruitment parameters of B. aegyptiaca, which might also have impacted soil fertility. We urge for intensive monitoring and awareness-raising programs to conserve this vulnerable tree species
Growth, mortality, exploitation rate and recruitment pattern of Octopus cyanea (Mollusca: Cephalopoda) in the WIO region: A case study from the Mafia Archipelago, Tanzania
Get PDFThis research article was published in Western Indian Ocean Journal of Marine Science, Volume 20, Issue 1, 2021.Octopus cyanea is a commercially important cephalopod in the Western Indian Ocean (WIO) region, but scientific
information to inform management strategies for the species is limited. A study was conducted in 2014, 2015,
2017 and 2018 to investigate biological parameters including growth, mortality, exploitation rates and recruitment
patterns in the sea around Mafia Archipelago, Tanzania. Virtual population analysis (VPA) indicated differential
mortality between two sampling sites; the lowest and highest fishing mortality of F = 1.5yr-1 and F = 2.7yr-1 were
observed in Bwejuu (Dorsal mantle length, DMT = 18-20 cm) and Jibondo (DMT = 8-12 cm) fishing villages, respec tively. The maximum exploitation rate (Emax), which gives the maximum relative yield per recruit, was estimated
at 0.380 and 0.379 for Jibondo and Bwejuu, respectively. The exploitation rates E 0.5, which corresponded to 50%
of the unexploited stock relative biomass per recruit, were estimated at 0.248 for Jibondo and 0.247 for Bwejuu.
These values differ greatly from the exploitation rates of 0.53 and 0.41 for Jibondo and Bwejuu, respectively, sug gesting that the stock of O. cyanea is probably being overfished both in terms of yield per recruit and biomass per
recruit. The stock-recruit pattern was observed to be continuous year-round, with the peak being between May and
July. Since the peak in recruitment of both areas coincides with the south-east monsoon (SE Monsoon) and the level
of maximum sustainable yield has been overshot, it is recommended that management plans are implemented
that will reduce effort while increasing biomass, for example, implementing temporal octopus fishery closures at
a village level
TB or not TB? Definitive determination of species within the Mycobacterium tuberculosis complex in unprocessed sputum from adults with presumed multidrug-resistant tuberculosis
Get PDFA research article was submitted by Tropical Medicine and International Health Volume26, Issue9 September 2021Objectives
Differences among Mycobacterium tuberculosis complex (MTC) species may predict drug resistance or treatment success. Thus, we optimised and deployed the genotype MTBC assay (gMTBC) to identify MTC to the species level, and then performed comparative genotypic drug-susceptibility testing to anti-tuberculosis drugs from direct sputum of patients with presumed multidrug-resistant tuberculosis (MDR-TB) by the MTBDRplus/sl reference method.
Methods
Patients with positive Xpert® MTB/RIF (Xpert) results were consented to provide early-morning-sputum for testing by the gMTBC and the reference MTBDRplus/sl. Chi-square or Fisher’s exact test compared proportions. Modified Poisson regression modelled detection of MTC by gMTBC.
Results
Among 73 patients, 53 (73%) were male and had a mean age of 43 (95% CI; 40–45) years. In total, 34 (47%), 36 (49%) and 38 (55%) had positive gMTBC, culture and MTBDR respectively. Forty patients (55%) had low quantity MTC by Xpert, including 31 (78%) with a negative culture. gMTBC was more likely to be positive in patients with chest cavity 4.18 (1.31–13.32, P = 0.016), high-quantity MTC by Xpert 3.03 (1.35–6.82, P = 0.007) and sputum smear positivity 1.93 (1.19–3.14, P = 0.008). The accuracy of gMTBC in detecting MTC was 95% (95% CI; 86–98; κ = 0.89) compared to MTBDRplus/sl. All M. tuberculosis/canettii identified by gMTB were susceptible to fluoroquinolone and aminoglycosides/capreomycin.
Conclusions
The concordance between the gMTBC assay and MTBDRplus/sl in detecting MTC was high but lagged behind the yield of Xpert MTB/RIF. All M. tuberculosis/canettii were susceptible to fluoroquinolones, a core drug in MDR-TB treatment regimens