Agroforestry

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Browsing Agroforestry by Funder "NACOSTI"

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    Publication
    Evaluation of Cercaricidal and Miracicidal Activity of Selected Plant Extracts Against Larval Stages of Schistosoma Mansoni
    (IISTE, 2016) Obare, Benter A.; Yole, Dorcas; Nonoh, James; Lwande, Wilber
    Schistosomiasis is a parasitic disease caused by blood-flukes of the genus Schistosoma. It is one of the most widespread of all human parasitic diseases, ranking second only to malaria in terms of its socioeconomic and public health importance in tropical and subtropical areas.More than 207 million people, 85% of whom live in Africa, are infected with schistosomiasis,and an estimated700 million people are at risk of infection in 76 countries.Control of schistosomiasis faces serious drawbacks of emergence of drug resistant parasites and molluscicide resistant snail hosts.Due to improper waste disposal,infected faecal matter enter water bodies such as canals rivers and springs where miracidia that hatch from parasite eggs develop into cercariae inside snail intermediate hosts and are infective to humans upon release in to the water.This study sought to evaluate the miracicidal and cercaricidal activity of selected plant extracts on larval stages of Schistosoma mansoni.Ten cercariae and miracidia were exposed to extract concentrations ranging from 10-150ppm.The most active extracts were Phytolacca dodecandra (LT50 10.84 and16.91minutes) and Solanum linaeanum (LT50 of 22.86 and 26.96 minutes) respectively that killed 50% of miracidia and cercariae in less than 30minutes.This was followed closely by Solanum americanum (LT50 31.02 and 31.89) and Anonna squamosa LT50 35.29 and 40.46minutes respectively.Piper nigrum was the least active recording LT50 46.84 and 56.75 of miracidia and cercaria respectively.Miracidia were more susceptible to extracts than cercariae.The higher susceptibility of miracidia to extracts has also been reported in other studies and it is advantageous since killing one miracidium prevents the formation of thousands of cercariae which are infective to humans.All the extracts killed larvae within one hour at concentration less than 100ppm and could be categorized as potent cercaricide and miracicides.
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    Publication
    MITIGATION OF IN-DOOR AIR POLLUTION AND GREEN HOUSE GASES BY USE OF RETROFITTED PRESSURE LAMP UTILIZING STRAIGHT VEGETABLE OIL
    (2014) Ogari, A. N.; H. M. Ndiritu; B. B. Gathitu
    The potential of traditional fossil fuels to be exhausted has increased of late. This has affected the many sectors of the economy which rely on petroleum products. Apart from depletion of fossil fuel and escalating oil prices, there is also need to conserve the environment to reduce global warming, ozone layer depletion, and climate change. This will reduce health issues associated with pollutant emissions from fossil fuel use. Among the efforts being made is the search for alternative renewable fuels. The objectives of the study were to study the performance characteristics of pressure lamps while using pure kerosene, kerosene-straight vegetable oil (SVO) blends and finally to modify the pressure lamp to utilize higher SVO/ kerosene blends. The performance of unmodified lamp was investigated and compared to that of a retrofitted pressure lamp utilizing straight vegetable oil/kerosene blends at 1.5 bar, 2.0 bar and 2.5 bar lamp pressure. Light output, carbon monoxide (CO) emission, carbon dioxide (CO2) emission, particulate matter (PM) emission, fuel consumption and heat generated were compared. Using a portable air compressor, air regulators and hoses, the lamps were maintained at constant pressures. Carbon dioxide data logger was used to monitor and record CO2 in real time. Easy Log carbon monoxide data logger was used to record carbon monoxide concentrations. University of Caronia, Barkley (UCB) particle monitor was used to monitor and record particulate matter in the room. Light output was measured using lux meters. Heat generated was measured using thermocouple. The unmodified lamp handled a maximum of 30% blend. Retrofitted lamp had an average of 17% CO reduction, 18% particulate matter reduction, 5.5% fuel consumption reduction, 10% temperature reduction, 5% CO2 increase while light output increased between 11% and 23% compared to the unmodified pressure lamp. In conclusion, the retrofitted pressure lamp utilizing SVO was designed and fabricated. This lamp emitted comparatively more light and CO2 but less PM and CO than the unmodified lamp at all pressures and fuel blends. The fuel consumed increased with increase in lamp pressure for both lamps. It is recommended that the lamps be tested in households to compare the outcome with the lab results. Further work should also be done to improve atomization of the fuel in lamps. Other emissions like NOx, and SOx should also be measured.