Farm Technologies and Production Risk in the Face of Climate Change in Tanzania

In countries where insurance and credit markets are thin or missing, production and consumption risks play a critical role in the choice and use of production inputs and adoption of new farm technologies. This paper investigated the effect of selected farm technologies and their risk implications in different rainfall patterns of Pangani river basin in Tanzania. Given the production risks posed by climate change, such information can be used by decision makers to identify appropriate agricultural practices that act as a buffer against climate change. Using a household and plot-level data set, Just and Pope framework was applied to using a quadratic production function to investigate the impact of selected farm technologies on average crop yields and the variance of crop yields, while controlling for several household and plot level factors. The results revealed that farm technologies perform differently in different rainfall areas, which underscores the importance of careful geographical targeting when promoting and up-scaling farm technologies adoption to climate change

A study of Antimicrobial Activity, Acute Toxicity and Cytoprotective Effect of a Polyherbal Extract in a Rat Ethanol-HCl Gastric Ulcer Model.

The decoction of the aerial parts of Rhynchosia recinosa (A.Rich.) Bak. [Fabaceae] is used in combination with the stem barks of Ozoroa insignis Del. (Anacardiaceae), Maytenus senegalensis (Lam.) Excell. [Celastraceae] Entada abyssinica Steud. ex A.Rich [Fabaceae] and Lannea schimperi (Hochst.)Engl. [Anacardiaceae] as a traditional remedy for managing peptic ulcers. However, the safety and efficacy of this polyherbal preparation has not been evaluated. This study reports on the phytochemical profile and some biological activities of the individual plant extracts and a combination of extracts of the five plants. METHODS: A mixture of 80% ethanol extracts of R. recinosa, O. insignis, M. senegalensis, E. abyssinica and L. schimperi at doses of 100, 200, 400 and 800 mg/kg body wt were evaluated for ability to protect Sprague Dawley rats from gastric ulceration by an ethanol-HCl mixture. ytoprotective effect was assessed by comparison with a negative control group given 1% tween 80 in normal saline and a positive control group given 40 mg/kg body wt pantoprazole. The individual extracts and their combinations were also tested for antibacterial activity against four Gram negative bacteria; Escherichia coli (ATCC 25922), Salmonella typhi (NCTC 8385), Vibrio cholerae (clinical isolate), and Klebsiella pneumoniae (clinical isolate) using the microdilution method. In addition the extracts were evaluated for brine shrimp toxicity and acute toxicity in mice. Phytochemical tests were done using standard methods to determine the presence of tannins, saponins, steroids, cardiac glycosides, flavonoids, alkaloids and terpenoids in the individual plant extracts and in the mixed extract of the five plants. RESULTS: The combined ethanolic extracts of the 5 plants caused a dose-dependent protection against ethanol/HCl induced ulceration of rat gastric mucosa, reaching 81.7% mean protection as compared to 87.5% protection by 40 mg/kg body wt pantoprazole. Both the individual plant extracts and the mixed extracts of 5 plants exhibited weak to moderate antibacterial activity against four G-ve bacteria. Despite Ozoroa insignis being toxic to mice at doses above 1000 mg/kg body wt, the other plant extracts and the combined extract of the 5 plants were tolerated by mice up to 5000 mg/kg body wt. The brine shrimp test results showed the same pattern of toxicity with Ozoroa insignis being the most toxic (LC50 = 10.63 mug/ml). Phytochemical tests showed that the combined extract of the five plants contained tannins, saponins, steroids, cardiac glycosides, flavonoids and terpenoids. Flavonoids, tannins and terpenoids are known to have antioxidant activity. CONCLUSION: The combined extract of the five plants exhibited a dose-dependent protective activity in the rat ethanol-HCl gastric ulcer model. The extracts also exhibited weak antibacterial activity against four Gram negative bacteria and low acute toxicity in mice and brine shrimps. Although the results support claims by traditional healers who use a decoction of the five plants for treatment of peptic ulcers, more models of gastric ulceration and proper animal toxicity studies are needed to validate possible clinical use of the polyherbal extract. It is also evident that the doses of the crude extracts showing protection of the gastric mucosa are too large for realistic translation to direct clinical application, but further studies using bioassay guided fractionation are important to either identify more practical fractions or active compound/s

Cytotoxic Screening of Some Tanzania Medicinal Plants

East and Central African Journal of Pharmaceutical Sciences Vol.6(3) 2003: 52-5

Elucidation of novel, alternative, fiber-reinforced iron-based pozzolanic composites as SCMs

The researchers pioneered incorporating waste materials exhibiting pozzolanic properties and waste fibers from diverse industrial/agricultural fields into the construction industry to formulate enhanced, greener supplementary cementitious composites (SCMs). This research focused objectively on the formulation/evaluation of low-CO2-embodied greener construction materials known as “novel, alternative, fiber-reinforced iron-based binary/ternary pozzolanic composites (abbreviated as NAFRIC)”. The composites incorporated iron powder (Fe), metakaolin (MK), pulverized fly ash (PFA), ground granulated blastfurnace slag (GGBS), palm ash, silica fume, and limestone, which are anticipated to absorb CO2 while producing siderite (ferrous carbonate FeCO3). All the NAFRIC mixes formulated in this study demonstrated up to 4–13% improvement in compressive strength and 70–130% in flexural strength with an enhanced rupture modulus/post-crack ductility. The ternary pozzolanic iron-based fiber-reinforced concrete (FRC) composites containing 8% MK + 10% PFA + 10% GGBS and steel/polypropylene/polyethylene terephthalate (PET) fibers performed the best with attaining up to 70 MPa compressive and up to 8.9 MPa flexural strengths. The sulfate testing evaluated the durability of NAFRIC SCMs formulated in a 1:2:3 ratio better than cement concrete control mix with a 1:1:3 ratio. NAFRIC specimens demonstrated minimal surface deterioration/elongation and negligible/no strength reduction after 270 days of concentrated sulfate attack. The microstructural analysis using X-ray diffraction/fluorescence, scanning electron microscopy/energy-dispersive analysis with X-ray spectroscopy supported the strength and durability parameters by showing minimal/no ettringite formation and increased calcium silicate hydrates gel formation due to the use of FeCO3 and pozzolans. The study demonstrated the sustainable use of these better-performing NAFRIC SCMs with 10–12% reduced embodied CO2 as eco-friendly high-strength SCMs with enhanced engineering/environmental benefits

Citizen scientist monitoring accurately reveals nutrient pollution dynamics in Lake Tanganyika coastal waters

Several studies in Lake Tanganyika have effectively employed traditional methods to explore changes in water quality in open waters; however, coastal monitoring has been restricted and sporadic, relying on costly sample and analytical methods that require skilled technical staff. This study aims in validating citizen science water quality collected data (nitrate, phosphate and turbidity) with those collected and measured by professional scientists in the laboratory. A second objective of the study is to use citizen scientist data to identify the patterns of seasonal and spatial variations in nutrient conditions and forecast potential changes based on expected changes in population and climate (to 2050). The results showed that the concentrations of nitrate and phosphate measured by citizen scientists nearly matched those established by professional scientists, with overall accuracy of 91% and 74%, respectively. For total suspended solids measured by professional and turbidity measured by citizen scientists, results show that, using 14 NTU as a cut-off, citizen scientist measurements of Sec-chi tube depth to identify lake TSS below 7.0 mg/L showed an accuracy of 88%. In both laboratory and citizen scientist-based studies, all measured water quality variables were significantly higher during the wet season compared to the dry season. Climate factors were discovered to have a major impact on the likelihood of exceeding water quality restrictions in the next decades (2050), which could deteriorate lake conditions. Upscaling citizen science to more communities on the lake and other African Great Lakes would raise environmental awareness, inform management and mitigation activities, and aid long-term decision-making

Experimental Study of a Lab Scale Hybrid Fixed Bed Gasifier

This research article published by Science Publishing Group, 2020Thermo-chemical conversion technologies (incineration, gasification and pyrolysis) have emerged as potential technologies for municipal solid waste management (MSWM). This is happening due to the increase of the need for clean and sustainable energy as a result of fossil fuel depletion. The increase in municipal solid waste (MSW) generation as well as land scarcity for MSW disposal is another reason in raising the potential for thermal technology. Incineration has been the most common thermo-chemical technology for solid waste disposal. However, due to environmental concern, gasification technology is currently becoming more preferable since it is environmental friendly for MSW disposal as well as energy recovery. The aim of this study is to analyze the flue gases obtained from the hybrid fixed bed gasifier during gasification of MSW. The fire was initiated by wood charcoal and six kilograms of MSW was fed in the gasifier. The combustion was supported by the air supplied by electric blower. The flue gas analyzer, TESTO 327-1 was used to analyze the concentration of CO, CO2 and O2. Results show that after 150 minutes of the gasification process, O2 concentration increased by 17.2% while CO and CO2 decreased by 0.0% and 3.77% respectively. The experimental results show that, during gasification process the O2 concentration was increasing with time while CO and CO2 concentration decreased

Imaging in the Land of 1000 Hills: Rwanda Radiology Country Report

Rwanda is an equatorial country in central Africa (Figure 1), and part of the East African Community of Burundi, Kenya, Uganda and Tanzania. It is a small country, just over 10,000 square miles. Its population of nearly 12,000,000 makes it the most densely populated state in continental Africa. Rwanda’s capital, Kigali, is a mile-high city. Its elevation makes the climate much cooler and more comfortable than a typical equatorial climate. The average annual temperature is 20.5 degrees Celsius with a narrow range – April, the coldest month has an average temperature of 20 degrees, whereas August, the warmest month has an average temperature of 21.5 degrees. Economically, Rwanda functions as a subsistence agricultural country but has been actively striving to emerge as a middle-income country. Its primary exports are coffee and tea. In 1994, the majority Hutu population carried out mass genocide of the ethnic Tutsi minority In a coordinated slaughter committed by neighbors against each other, and with low-technology weapons like machetes, nearly 1,000,000 people were killed in 100 days (1). The country was devastated. Immediately post-genocide, Rwanda was one of the poorest countries in the world with nearly 70% of the population living below the poverty line (2). Until 1997, Rwanda had the lowest life expectancy of any country in the world (3). The physician work force was depleted due to the direct and indirect consequences of the Rwandan Genocide. Since this time there has been a steady economic recovery (4), along with remarkable medical recovery. Average life expectancy nationwide, only 27 years in the early 1990s, has now reached 63 years (3). Since the 2012 publication (5) highlighting its advances, radiology in Rwanda has benefitted from the capital infusion that has helped to propel the overall growth in the economic and health sectors. As of 2012, there are five national referral hospitals, 41 district hospitals, one military hospital and 451 health centers (6). The health centers are staffed primarily by nurses, while the district hospitals are staffed by general practitioners (graduates of medical school without a post-graduate education). Of the 625 total physicians in the country in 2011, 150 had completed residency (3)

Effect of interventions to reduce malaria incidence among military personnel on active duty: study protocol for a cluster randomised controlled trial of the impact of etofenprox-treated uniforms, permethrin-treated uniforms and DEET insect repellent

BACKGROUND: While there is strong evidence that bite protection methods such as permethrin-treated clothing and topical insect repellents are protective against insect bites, there are few studies assessing the impact on malaria infection. This study will estimate the protective efficacy of treated uniforms and DEET insect repellent on the incidence of malaria infection among military personnel in an operational setting. Permethrin-treated uniforms used with DEET lotion will be compared to etofenprox-treated uniforms with DEET lotion. The effect of DEET lotion will be estimated by comparing permethrin-treated uniforms with DEET or placebo lotion. METHOD: A cluster randomised double-blind placebo-controlled trial is planned to evaluate the effectiveness of the interventions on preventing malaria infections in soldiers on active duty at Mgambo National Service Camp in Tanga, Tanzania. The arms are (1) permethrin-treated uniform with 30% DEET liposome formula; (2) permethrin-treated uniform with placebo lotion; (3) candidate insect repellent system, i.e. etofenprox-treated uniform with 30% DEET liposome formula; and (4) placebo, i.e. untreated uniforms with placebo lotion. The primary outcome is the incidence of Plasmodium falciparum malaria infection detected by polymerase chain reaction (PCR) by active case detection using surveys every 2 weeks for 12 months. Rapid diagnostic tests will be used for the diagnosis of participants with symptoms. The unit of randomisation will be combania: companies formed by recruits aged 18 to 25 years; combania do activities together and sleep in the same dormitory. Unequal randomisation will be used to optimise statistical power for the primary comparison between permethrin-treated uniforms with DEET and etofenprox-treated uniforms with DEET. DISCUSSION: This trial will provide the estimate of the effects of permethrin with DEET compared to those of the new fabric treatment etofenprox with DEET and any additional effect of using DEET. The results will inform strategies to protect military personnel and civilians who have more outdoor or occupational malaria exposure than the general public. TRIAL REGISTRATION: ClinicalTrials.gov NCT02938975

Simulation and performance analysis of municipal solid waste gasification in a novel hybrid fixed bed gasifier using Aspen plus

This research article published by Taylor & Francis Online, 2020Thermochemical conversion technologies (incineration, gasification, and pyrolysis) have emerged as potential technologies for municipal solid waste management. Incineration is the most common thermo-chemical technology widely used in developing countries; however, the process pollutes the environment. Therefore, this study suggests a novel hybrid fixed bed gasifier for gasification of municipal solid waste (MSW). The gasifier model was developed using the Advanced System for Process Engineering Plus (ASPEN Plus) software to accommodate the four gasification stage (drying, pyrolysis, combustion, and gasification). The aim of developing a novel hybrid fixed bed gasifier is to combine the advantages of downdraft and cross-flow gasifiers in one system and minimize its disadvantages. This combination has revealed the way to a gasifier design that accommodates feedstock with high moisture content (≈ 60%) while maintaining or improving syngas output composition. The analysis of operating parameters such as temperature and equivalence ratio (ER) was also investigated. The results showed that the moisture content (MC) was reduced from 59.8 wt% to 6.8 wt%. The syngas output was highly affected by the changes in temperature as well as ER. High temperature increases H2and CO output composition. The behavior was different for the case of ER where it was observed that H2 and CO decreases while CO2 andH2Oincreases between ER = 0.1 to 0.4 and then starts decreasing gradually. In general, the developed hybrid fixed bed gasifier exhibited an increase inH2 and CO in the producer gas. At this situation, the carbon conversion efficiency of 62.35% and a gasifier conversion efficiency of 54.5% were realized. This suggests the suitability of hybri