Ivermectin also called the wonder drug has been used over the years to control internal and external parasites in livestock. In humans it has been used for the control of several neglected tropical diseases. With regards to efforts to control malaria, mass drug administration (MDA) of ivermectin in humans and livestock has been considered as a potential tool. This is due to challenges in malaria preventive strategies such as insecticide resistance in mosquitoes, shift in their behaviors and residual transmission. Ivermectin reduces malaria transmission by targeting the mosquito nervous system resulting in their death. Ivermectin and its metabolites could have great impacts on the environment as well as human and health. In temperate settings, impacts of ivermectin in the environment were studied due to intense use of the drug in livestock. There is also a necessity to study effects of ivermectin in the tropics before MDA for malaria vector control. Despite its great potential, previous studies done recorded toxicity and sensitivity of the drug to most arthropods mainly dung organisms because ivermectin is released in dung at high concentrations for the case of livestock. With dung organism activity being affected the dung decomposition process is disrupted, cattle avoid these grazing areas leading to financial losses. In the tropics where there is a high number of malaria cases, there is no information on the impacts of the drug in the environment. We placed standardized dung pats from ivermectin-treated and control cattle to determine the effect of ivermectin on dung degradation and dung fauna in Tanzania. For the dung degradation study, at 15, 30 and 45 days post placement, we observed a total of 220 dung pats in the field. We measured termite colonization; wet weight of the entire pat; water content; dry weight of the 10 g subsamples and organic matter from subsamples and the whole pat. For the dung fauna study, we collected fresh dung 3, 10 and 29 days post treatment and put the pats out in the field to be colonized by insects before being transferred to emergence traps. We also did a semi field study where we collected dung pats 1,2,3 and 5 days post treatment to obtain larvae counts. We qualitatively assessed insect larvae activity in the field experiment and observed and counted larvae in the semi field study. We found that termites colonized pats from cattle treated with ivermectin more readily compared to controls (p < 0.001). Compared to control pats, the treated pats' wet weight decreased more slowly on day 15 (p < 0.001), day 30 (p < 0.001), and on day 45 (p = 0.037). Percent dry weight increased over time and similarly between the treatments as water content decreased. Organic matter of the 10g sub samples was similar between the treatments. Total organic matter in the whole pats showed significant differences on day 15 (p < 0.001), and day 30 (p = 0.003), but not on day 45 (p = 0.291). Qualitatively, we observed that pats from treated cattle had less insect larvae activity as compared to controls in the field study. In the semi field study, we counted less larvae in the pats from ivermectin-treated cattle than in the control pats (p < 0.001). Our results indicate that ivermectin and its residues affect dung degradation and dung fauna in tropical savanna settings, and the environmental safety may be at risk upon mass drug administration in livestock. / Master of Science in Life Sciences / Ivermectin is a drug commonly used in livestock and humans to control most parasitic infections. Malaria is a disease transmitted by female Anopheles mosquitoes and prevalent in tropical regions mostly the sub-Saharan Africa. There are efforts worldwide to reduce transmission of malaria such as the used of insecticide treated bed nets as well as use of repellents and spraying insecticides indoors. These efforts are challenged by insecticide resistance in mosquitoes, change in mosquito behavior as well as remaining malaria cases after such interventions are applied. With such challenges comes a need to use ivermectin which has the ability to kill mosquitoes. Despite its great potential, evidence from temperate regions record that ivermectin affects the environment by decreasing dung insect activity, affecting the developmental process and causing a delay in dung decomposition. These effects cause cattle to avoid such pasture areas, resulting in an increase in pest pressure and affecting the economy in general. In the tropics where malaria is prevalent and plans are in place to use ivermectin in mass drug administration for mosquito control, there is a need to look at the environmental impact of the drug. We placed 1 kg dung pats from ivermectin-treated and control cattle to determine the effect of ivermectin on dung degradation and dung fauna in Tanzania. For the dung degradation study; at 15, 30 and 45 days after pats were placed in the field, we observed a total of 220 dung pats. We measured termite colonization; wet weight of the entire pat; water content; dry weight of the 10 g subsamples and organic matter from subsamples and the whole pat. For the dung fauna study, we collected fresh dung 3,10 and 29 days post treatment and put the pats out in the field to be colonized by insects before being transferred to emergence traps. We also did a semi field study where pats were collected 1,2,3 and 5 days post treatment to obtain larvae counts. We qualitatively assessed insect larvae activity in the field experiment and observed and counted larvae in the semi field study. We found that termites colonized pats from cattle treated with ivermectin more readily compared to controls, and treated pats' wet weight decreased more slowly. Dry weight of dung increased as water content decreased with no differences between the treatments. Organic matter of the subsamples did not differ in the treatments but the average mass of organic matter of the individual dung pats decreased slower in ivermectin-treated pats. Qualitatively, we observed that pats from treated cattle had less insect larvae activity as compared to controls in the field study. In the semi field study, we counted more larvae in control pats than the ivermectin pats. Our results indicate that ivermectin and its residues affect dung degradation and dung fauna in tropical savanna settings, and the environmental safety may be at risk upon mass drug administration setting.

Made available in DSpace on 2014-10-09T12:51:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:30Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:04/04148-3

Made available in DSpace on 2014-10-09T12:35:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:51Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:51:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:30Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:04/04148-3

Made available in DSpace on 2014-10-09T12:35:47Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:51Z (GMT). No. of bitstreams: 0 / Os íons terras raras apresentam propriedades espectroscópicas diferenciadas e números de coordenação entre 6 e 12 e seu estado de oxidação mais comum é o íon trivalente. Apesar de esses íons apresentarem uma baixa intensidade de luminescência, em função de sua baixa absortividade molar, esses são capazes de formar complexo onde o ligante absorva luz e transfira para o centro metálico essa energia, fenômeno conhecido como efeito antena. Essas propriedades tornam os seus complexos alvos de estudos como marcadores em ensaios imunoluminescentes, aliado ao uso de nanopartículas poliméricas. Todos esses fatores podem ser utilizados para a montagem de uma metodologia para o diagnóstico da doença de Chagas, doença tropical negligenciada, que apesar de seus mais de 100 anos após descoberta, ainda possui diversas questões em aberto e sem estudo aprofundado. Dessa maneira, propomo-nos a sintetizar e caracterizar nanopartículas de PHB misturadas aos complexos de terras raras, especificamente, complexos -dicetona - Tb3+ , Sm3+ , Gd3+, ou Eu3+. Pretende-se ligar essas nanopartículas a um espaçador como o glutaraldeído ou então diretamente a um anti-IgG humano e assim, num acoplamento antigeno-anticopo verificar sua emissão de luminescência para detecção de soro positivo para a doença. Dessa forma, obtém-se um biomarcador luminescente para diagnóstico da doença de Chagas. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Despite significant vector control advancements in the past years, the current malaria trends suggest that new control strategies are urgently required. These new approaches should address the current frontline intervention challenges like increasing insecticide resistance in mosquitoes and residual transmission issues. Insecticide-treated livestock (ITL) is one of the novel potential strategies to overcome the above challenges. ITL involves treating livestock near humans with an insecticide like ivermectin (IVM) to kill zoophagic malaria vectors. However, ivermectin pharmacokinetics data suggests that most IVM-administered drugs remain intact, and more than 90 % of this drug is eliminated in feces. Biological metabolites: 3′′-O-demethylivermectin (3DI) and 24-hydroxymethyl ivermectin (24OHI) are also excreted in feces. Therefore, using manure from treated cattle as fertilizers contaminates the soil, ground, and surface water with IVM or its metabolites through leaching and hydraulic water flow affecting the soil and aquatic ecosystems. Contemplating the contamination impacts, these drugs' environmental fate and effects could be regarded before massive IVM applications. Many researchers have tried to address this subject in temperate regions compared to the tropics, where IVM is urgently needed. Regional discrepancies such as soil types and climate can independently and dependently determine the fate and impact of ivermectin. Our research investigates the environmental fate of IVM and its primary biological metabolites. Laboratory and field studies in Tanzania and Virginia were conducted to simulate the difference between tropical and temperate climates. Soil and soil-manure mixture spiked with IVM were layered into two 5 mm layers in columns exposed to natural sunlight. The remaining IVM and its primary metabolite were quantified using Liquid Chromatography with a tandem mass spectrometry detector (LC-MS/MS. These compounds degraded up to 1.5 times faster in Tanzania than in Virginia, depending on temperature, soil depths and type, organic matter, and soil moisture. When IVM is subcutaneously injected into cattle, drug residues and metabolites: 3DI and 24OHI are excreted in feces following a positive skewed Poisson distribution profile. IVM, 3DI, and 24OH were found to degrade rapidly when cattle pats when exposed to the field. Since we conducted our study in the Summer, no IVM or its metabolites leached into the soil beneath. The obtained half-lives suggest that ivermectin's massive drug administration has little to worry about, primarily when the dung from treated cattle is spread into the field in thin layers in the Summer before farm application. / Doctor of Philosophy / Despite significant vector control advancements in the past years, the current malaria trends suggest that new control strategies are urgently required. These new approaches should address the current frontline intervention challenges like increasing drug resistance in mosquitoes and residual transmission issues. Treating cattle with ivermectin is one of the novel potential strategies to overcome the above challenges. This strategy is effective because the amount of ivermectin (IVM) found in the blood of treated cattle is enough to kill malaria vectors feeding on them. However, the literature suggests that most IVM-administered drugs remain intact, and more than 90 % of this drug is eliminated in feces. Metabolite bioproducts: 3″-O-demethylivermectin (3DI) and 24-hydroxymethyl ivermectin (24OHI) are also excreted in feces. Therefore, using manure from treated cattle as fertilizers contaminates the soil, ground, and surface water with IVM or its metabolites through leaching and hydraulic water flow affecting the soil and aqua ecosystems. Contemplating the contamination impacts, these drugs' environmental fate and effects could be regarded before massive IVM applications. Many researchers have tried to address this subject in temperate regions compared to the tropics, where IVM is more needed. Regional discrepancies such as soil types and climate can independently and dependently determine the fate and impact of ivermectin. Our research investigates the environmental fate of IVM and its primary bioproducts. Laboratory and field studies in Tanzania and Virginia were conducted to simulate the difference between tropical and temperate climates. Soil and soil-manure mixture spiked with IVM were layered into two 5 mm layers in columns exposed to natural sunlight. The remaining IVM and its primary metabolite were quantified on the appropriate instrument. These compounds degraded up to 1.5 times faster in Tanzania than in Virginia, depending on temperature, soil depths and type, organic matter, and soil moisture. When IVM drug is injected into cattle, the intact drug and its bioproducts: 3DI and 24OHI, are eliminated in feces following a favorable skewed normal distribution profile. IVM, 3DI, and 24OH were found to degrade rapidly when cattle pats when exposed to the field. Since we conducted our study in the Summer, no IVM or its bioproducts leached into the soil beneath. The obtained data suggest that ivermectin's massive drug administration has little to worry about, primarily when the dung from treated cattle is spread into the field in thin layers in the Summer before farm application.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-01-07T16:15:17Z No. of bitstreams: 0 / Made available in DSpace on 2015-01-07T16:15:17Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-01-07T16:15:17Z No. of bitstreams: 0 / Made available in DSpace on 2015-01-07T16:15:17Z (GMT). No. of bitstreams: 0 / A atmosfera terrestre contém nitrogênio e oxigênio, sendo este último, um composto altamente reativo e fundamental ao desenvolvimento e manutenção da vida. Além desses gases, diversos outros compostos em pequenas concentrações, os quais podem atuar como reagentes e/ou catalisadores também a compõe. Os compostos gasosos variados e material particulado (orgânico e inorgânico) de diferentes dimensões lançados constantemente à atmosfera são provenientes de fontes diversas. Tais fontes podem ser de origem natural ou antrópica e ainda, podem ser pontuais, difusas, primárias, secundárias, móveis e/ou estacionárias. Os processos envolvendo transformações químicas na atmosfera são extremamente importantes porque tendem a manter a sua composição em estado estacionário. A vegetação, que constitui uma fonte natural, é responsável pela emissão de grandes quantidades de compostos carbonados para a atmosfera. Dentre os vários compostos orgânicos emitidos da superfície do planeta, destacam-se em particular, alguns gases traços, denominados compostos orgânicos voláteis (COVs). A emissão dos compostos orgânicos voláteis pela vegetação ocorre, em escala global, predominantemente nos trópicos ou nos meses de verão em outras regiões. As reações fotoquímicas dos compostos orgânicos voláteis desempenham um papel diferenciado e importante na química da troposfera, podendo alterar de forma significativa a concentração de ozônio em áreas tanto urbanas quanto rurais. O presente projeto contempla o estudo de alguns dos inúmeros compostos orgânicos voláteis de origem biogênica (COVBs) emitidos pela vegetação constituinte, das regiões da Floresta Amazônica, da Mata Atlântica e da floresta Tropical da Guiana Francesa, comparando-se os dados de saída gerados pelos Modelos MOZART-4 e CAM-Chem. A escolha dos sítios experimentais para realização deste estudo se deu em parte em função da importância dos locais em termos de biodiversidade, extensão territorial, influência na climatologia (local e/ou regional), bem como também em função da acessibilidade, proximidade a centros urbanos e alterações devido à influência humana. O procedimento metodológico adotado para coleta das amostras de COVBs se deu por meio da técnica conhecida como acumulação de vórtices turbulentos (Relaxed Eddy Accumulation - REA), a qual faz uso de um dispositivo coletor denominado acumulador compacto de vórtices turbulentos (Compact Relaxed Eddy Accumulator - CREA). As amostras gasosas de COVBs foram coletadas por meio de cartuchos comerciais apropriados, compostos por diferentes materiais adsorvedores que apresentavam afinidade química também diferenciada para os variados compostos aos quais foram expostos. Estudos primários para determinação da natureza dos cartuchos que foram utilizados neste projeto foram realizados, a fim de se obter dispositivos adequados a este propósito. Os resultados evidenciam, como esperado, que a presença de isopreno é predominante em todos os sítios experimentais, sendo sua concentração média diária máxima de 5,0 ± 0,3 &mu;g/cm3 registrada na Amazônia e de 8,0 ± 0,4 &mu;g/cm3 (concentração diária) na floresta da Guiana Francesa, seguido pelo alfa-pineno cuja concentração máxima obtida foi de aproximadamente 1,6 ± 0,08 &mu;g/cm3 no último sítio experimental, ambos detectados na estação seca. A emissão de isopreno e dos monoterpenos ocorreu de forma mais acentuada na época seca em comparação ao período úmido. Contudo, observou-se em algumas situações uma pequena discrepância. De maneira geral os resultados gerados pelos modelos estão subestimados, como exceção do parâmetro de radiação fotossinteticamente ativa (PAR), o que indica que a defasagem entre os resultados observados e os simulados pode estar relacionada parâmetros de OH-, NOx e em algumas reações químicas fotoquímicas envolvendo o ozônio. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

[pt] Este trabalho examina o problema da atenuação por chuvas na propagação da energia em freqüências superiores a 10 ghz, com especial ênfase na aplicação dos resultados em regiões de clima tropical. São discutidos em detalhes os métodos existentes para caracterizar a distribuição estatística pontual da precipitação em uma região. Apresenta-se uma solução semi-empírica para a questão da não uniformidade espacial da distribuição de chuvas em um percurso, empregando o conceito de precipitação equivalente e dados de inúmeros trabalhos experimentais publicados na literatura técnica para diversas freqüências e distancias. Finalizando é feito um exemplo ilustrativo do método proposto, tomando por base os dados pluviográficos do Rio de Janeiro. / [en] This work deals with the problem of rainfall attenuation at frequencies above 10 GHz. Particular enphasis is given to the application of the final results for communications links in a tropical region. The proposed nethods to characterize the punctual rainfall statistical distribution in a specific region are discussed in detail. A solution to the problem of a non-uniform spatial distribution of the rainfall through the propagation path is presented, the concept of equivalent precipitation being applied. A big amount of experimental data from the technical literature was utilized, for different frequencies and distances. Finaly, an example of the proposed method is presented, along with an application based upon Rio de Janeiro rain data.

Forested watersheds play a dominant role in the global hydrological cycle. Very few experimental observatories especially in tropical forested regions of India have been undertaken. This study has been initiated for this reason and to gain insights into functioning of the hydrological system in such climatic conditions. This study involves experimental setup of a watershed, it’s monitoring till date, modelling of the hydrological processes observed and the challenges in modelling components of the water balance in this watershed. A Small Experimental Watershed of 4.3 Km2 was set up at Mule Hole, in South India along the Kerala-Karnataka State borders, and is situated inside the Bandipur National park. After an overview of watershed studies, review of literature related to forest watershed studies and processes in the first two chapters, Chapter 3 introduces the study area, Mule Hole Experimental Watershed and explains the methodology used to study this watershed. Model SWAT was used initially to simulate the water balance components. A brief description of the model, methodology adopted and discussion on the results obtained is presented in Chapter 4. The watershed initially modelled as an ungauged watershed using the default parameters in the model, simulated very high groundwater contribution to the runoff. The calibrated model although performed favourably for annual average values and monthly calibration, the daily calibration was unsatisfactory. An auxiliary study on quantification of actual and potential evapotranspiration (ET0) has been carried out in Chapter 5 . Ten methods including Penman-Montieth were compared and evaluated for efficacy of the methods. All methods except for Hargreaves method showed agreement with the Penman-Montieth for annual average values. Priestly-Taylor method was found be the best estimator in comparison with Penman-Montieth method, when used to estimate AET. Adjusted Hargreaves and FAO Blaney -Criddle method were found to be very useful when few or limited climatic data were available for estimation of Potential evapotranspiration. A multidisciplinary approach of estimating recharge consisting of chloride mass balance technique coupled with study of water table fluctuations and groundwater flow analytical modelling has been attempted in Chapter 6. Direct and localized recharge was estimated at 45 mm/yr and indirect recharge 30 mm/yr for the monitored years in the watershed. The low values of recharge rates implied an unexpected very high evapotranspiration rate. It may be inferred that in the absence of groundwater flow to the stream, the recharge joins groundwater flow as outflow of the hydrologic system. An integrated lumped model incorporating the regolith zone and the capability of the tree roots to access this store is presented in Chapter 7. The model was able to simulate the pattern of lag-time between water table rise was observed in shallow piezometers in comparison with hillslope piezometers. The patterns of water table variation among the different hillslope piezometers suggest that they are linked with local processes and not by a regional aquifer dynamics. This study shows that water uptake, combined with the spatial variability of regolith depth, can account for the variable lag time between drainage events and groundwater rise observed for the different piezometers. Chapter 8 discusses the results, conclusions derived from this study and possibility of further scope of studies.