This thesis dissertation assessed workers who work in poultry barns and their occupational environment in relation to the type of bird housing in which they were exposed (cage-housed birds (CH) or floor-housed birds (FH)) and examined the environmental variables including dust and endotoxin and potential relationships to respiratory symptoms of workers. <p>A cross sectional study was undertaken to assess the environmental exposure levels and respiratory health effects of workers who worked in CH and FH poultry operations. The respiratory results suggested an asthma-like syndrome in these workers. Workers who worked in CH facilities reported greater current and chronic respiratory symptoms and significantly greater current and chronic phlegm as compared to workers from FH facilities. Workers from CH poultry facilities were exposed to greater endotoxin load than workers from FH facilities, but workers from FH operations were exposed to greater levels of total dust. It was found that endotoxin load (EU/mg) was a significant predictor of chronic phlegm for all poultry workers.<p>The effects on dust and endotoxin measurements when utilizing a Marple impactor with greased or ungreased impaction surfaces when sampling in an agricultural environment were unknown, and the potential for effects was tested. There were no significant differences in the aerosol mass median aerodynamic diameters between the greased and ungreased Marple impactors. Endotoxin analysis results appeared to be influenced by impaction grease particularly when very low amounts of endotoxin were present. <p>Size fractioning the dust and endotoxin using Marple impactors in CH and FH poultry operations showed that endotoxin load (EU/mg) was significantly higher in the respirable fraction of area samples in CH poultry operations as compared to FH operations. There were no differences in endotoxin load in the non-respirable size fractions for area samples between CH and FH operations. FH poultry operations had significantly greater dust mass and dust concentration in both respirable and non-respirable fractions for FH operations. There was significantly greater endotoxin load (EU/mg) in the 3.5-6.0 micron size fraction for the CH poultry operations as compared to the FH operations.

This thesis dissertation assessed workers who work in poultry barns and their occupational environment in relation to the type of bird housing in which they were exposed (cage-housed birds (CH) or floor-housed birds (FH)) and examined the environmental variables including dust and endotoxin and potential relationships to respiratory symptoms of workers. <p>A cross sectional study was undertaken to assess the environmental exposure levels and respiratory health effects of workers who worked in CH and FH poultry operations. The respiratory results suggested an asthma-like syndrome in these workers. Workers who worked in CH facilities reported greater current and chronic respiratory symptoms and significantly greater current and chronic phlegm as compared to workers from FH facilities. Workers from CH poultry facilities were exposed to greater endotoxin load than workers from FH facilities, but workers from FH operations were exposed to greater levels of total dust. It was found that endotoxin load (EU/mg) was a significant predictor of chronic phlegm for all poultry workers.<p>The effects on dust and endotoxin measurements when utilizing a Marple impactor with greased or ungreased impaction surfaces when sampling in an agricultural environment were unknown, and the potential for effects was tested. There were no significant differences in the aerosol mass median aerodynamic diameters between the greased and ungreased Marple impactors. Endotoxin analysis results appeared to be influenced by impaction grease particularly when very low amounts of endotoxin were present. <p>Size fractioning the dust and endotoxin using Marple impactors in CH and FH poultry operations showed that endotoxin load (EU/mg) was significantly higher in the respirable fraction of area samples in CH poultry operations as compared to FH operations. There were no differences in endotoxin load in the non-respirable size fractions for area samples between CH and FH operations. FH poultry operations had significantly greater dust mass and dust concentration in both respirable and non-respirable fractions for FH operations. There was significantly greater endotoxin load (EU/mg) in the 3.5-6.0 micron size fraction for the CH poultry operations as compared to the FH operations.

In this study, annual variations in biochemical composition of seston and zooplankton community were investigated to characterize the nutritional environment of zooplankton in the Mersin Bay, NE Mediterranean Sea. For this goal, seawater and zooplankton samples were collected at monthly intervals from two stations / one representing coastal and other representing open waters characteristics from November 2004 to January 2006. Seawater samples were collected with Niskin bottles from the sea surface. Zooplankton samples were collected both in the horizontal and vertical plane by towing a Nansen net (70 cm mouth diameter with 112 &micro / m mesh). Surface seston chl-a, lipid, protein and carbohydrate concentrations were measured by fractionating seawater into three different size groups, 0.7-2.7, 2.7-18 and &gt / 18 &micro / m representing pico, nano and micro particulates in the seston. Zooplankton biomass and abundance were determined at four size fractions: 112-200, 200-500, 500-1000 and &gt / 1000 &micro / m / dry and organic weights were measured by gravimetric method and major taxonomic groups of zooplankton was identified under stereo-microscope. The nearshore station was always more productive than the offshore station in terms of chl-a, particulate organic matter (POM: protein+lipid+carbohydrate), zooplankton abundance and biomass. Chl-a maxima occured in spring and autumn at both stations. Very low chl-a concentrations at the offshore station (0.02-0.35 &micro / g L-1) confirmed oligotrophic character of the Northeastern Mediterranean. The highest chl-a concentration (2.4 &micro / g L-1) was observed in March 2005 at the nearshore station due to the input of Lamas River nearby. POM varied from 42.1 &micro / g L-1 (in January 2006) to 1082 &micro / g L-1 (in March 2005) and 53.7 &micro / g L-1 (in January 2006) to 246 &micro / g L-1 (in May 2005) at the nearshore and offshore stations, respectively. The oligotrophy of this system was indicated by the extremely low particulate lipid, protein and carbohydrate concentrations (1-3 times lower than in more productive systems). The most evident characteristic of this oligotrophic environment was the dominance of pico-POM throughout the study period, accounting for 31&ndash / 65 % of the total carbohydrates, proteins, lipids and chl-a. The prt:cho ratio was generally lower than 1 (low in organic nitrogen). Carbohydrate was the dominant biochemical component at both stations. Zooplankton varied during the sampling period, and they showed two peak abundances, in spring and autumn, with small increase in summer. The higher biomasses of zooplankton were observed in summer and autumn in the entire water column, but in spring and autumn periods in the surface water. Zooplankton data showed that 200-500 and 112-200 &micro / m size fractions were dominant in abundance at both stations. However, 200-500 &micro / m size fraction was dominant in zooplankton biomass at nearshore, whereas &gt / 1000 &micro / m size fraction was at offshore station. Copepods were the most abundant zooplankton group and dominated the distribution of total zooplankton, followed by crustace nauplii, appendicularia, cladocera and pteropoda.

Para estimar a distribuição das diferentes classes de tamanho do fitoplâncton através de imagens de sensoriamento remoto e as propriedades bio-ópticas esse trabalho foi realizado em duas regiões. Durante o inverno de 2007 foi feito o cruzeiro com 58 estações hidrográficas sobre Banco de Abrolhos e adjacências e em 2009 o cruzeiro hidrográfico a longo do Atlântico Sul entre as plataformas continentais do Brasil e da África, limitado pelas latitudes 20ºS e 30ºS. Os valores de clorofila_a total mostraram que a região do Banco de Abrolhos é oligotrófica, com baixa produtividade primária e sustenta pelas células do picoplâncton que são influenciadas diretamente pela disponibilidade de fosfato. A matéria orgânica dissolvida (cdom) foi o constituinte bio-óptico com os maiores valores. Sobre a plataforma Africana, a presença da Corrente de Bengala influenciou diretamente nas altas concentrações da clorofila_a e nos tamanhos das células do fitoplâncton. A biomassa dessa região de ressurgência é sustentada por células principalmente do nanoplâncton. As propriedades bio-ópticas da plataforma continental da África são diferentes tanto em valores como nas contribuições relativas das observadas na costa do Brasil. Sobre a plataforma Africana a absorção do fitoplâncton foi o constituinte que prevaleceu sobre os demais (adetritos e cdom). / The distribution of different classes of size phytoplankton are estimated using remote sensing and the bio-optical properties this work was carried out in two regions. During the winter of 2007 the cruisers was done with 58 hydrographic stations on Abrolhos Bank and adjacencies and in 2009 the hydrographic cruise of South Atlantic between the continental shelf of Brazil and Africa, limited by the latitudes 20ºS and 30ºS. The values of chlorophyll a showed that the region of the Bank is oligotrophic area, with low primary productivity and supports for cells of picoplankton that are influenced straightly by the availability phosphate. The organic dissolved matter (cdom) was the constituent bio-optical with the highest values. On the African continental shelf, the presence of Benguela Current influenced straightly the high concentrations of chlorophyll a and the sizes of phytoplankton cells. The upwelling biomass of this region is supported by nanoplankton. The bio-optical properties of continental shelf of Africa are different from Brazilian shelf, the values and in the relative contributions the phytoplankton absorption was prevailed over the others constitute (adetritos and cdom).

Para estimar a distribuição das diferentes classes de tamanho do fitoplâncton através de imagens de sensoriamento remoto e as propriedades bio-ópticas esse trabalho foi realizado em duas regiões. Durante o inverno de 2007 foi feito o cruzeiro com 58 estações hidrográficas sobre Banco de Abrolhos e adjacências e em 2009 o cruzeiro hidrográfico a longo do Atlântico Sul entre as plataformas continentais do Brasil e da África, limitado pelas latitudes 20ºS e 30ºS. Os valores de clorofila_a total mostraram que a região do Banco de Abrolhos é oligotrófica, com baixa produtividade primária e sustenta pelas células do picoplâncton que são influenciadas diretamente pela disponibilidade de fosfato. A matéria orgânica dissolvida (cdom) foi o constituinte bio-óptico com os maiores valores. Sobre a plataforma Africana, a presença da Corrente de Bengala influenciou diretamente nas altas concentrações da clorofila_a e nos tamanhos das células do fitoplâncton. A biomassa dessa região de ressurgência é sustentada por células principalmente do nanoplâncton. As propriedades bio-ópticas da plataforma continental da África são diferentes tanto em valores como nas contribuições relativas das observadas na costa do Brasil. Sobre a plataforma Africana a absorção do fitoplâncton foi o constituinte que prevaleceu sobre os demais (adetritos e cdom). / The distribution of different classes of size phytoplankton are estimated using remote sensing and the bio-optical properties this work was carried out in two regions. During the winter of 2007 the cruisers was done with 58 hydrographic stations on Abrolhos Bank and adjacencies and in 2009 the hydrographic cruise of South Atlantic between the continental shelf of Brazil and Africa, limited by the latitudes 20ºS and 30ºS. The values of chlorophyll a showed that the region of the Bank is oligotrophic area, with low primary productivity and supports for cells of picoplankton that are influenced straightly by the availability phosphate. The organic dissolved matter (cdom) was the constituent bio-optical with the highest values. On the African continental shelf, the presence of Benguela Current influenced straightly the high concentrations of chlorophyll a and the sizes of phytoplankton cells. The upwelling biomass of this region is supported by nanoplankton. The bio-optical properties of continental shelf of Africa are different from Brazilian shelf, the values and in the relative contributions the phytoplankton absorption was prevailed over the others constitute (adetritos and cdom).

Soil organic matter (OM) is a complex mixture of compounds, mainly derived from plants and microbes at various states of decay. It is part of the global carbon cycle and is important for maintaining soil quality. OM protection is mainly attributed to its association with minerals. However, clay minerals preferentially sorb specific OM structures, and clay sorption sites become saturated as OM concentrations increase. Therefore, it is important to examine how OM structures influence their association with soil minerals, and to characterize other protection mechanisms. Several techniques, which provide complementary information, were combined to investigate OM composition: Biomarker (lignin phenol, cutin-OH acid, and lipid) analysis, using gas chromatography/mass spectrometry; solid-state 13C nuclear magnetic resonance (NMR) spectroscopy; and an emerging method, solution-state 1H NMR spectroscopy. OM composition of sand-, silt-, clay-size, and light fractions of Canadian soils were compared. It was found that microbial-derived and aliphatic structures accumulated in clay-size fractions, and lignin phenols in silt-size fractions may be protected from further oxidation. Therefore, OM protection through association with minerals may be structure-specific. OM in soils amended with maize leaves, stems, and roots from a biodegradation study were also examined. Over time, lignin phenol composition, and oxidation; and aliphatic structure contribution changed less in soils amended with leaves compared to soils amended with stems and roots. Compared to soils amended with leaves and stems, amendment with roots may have promoted the more efficient formation of microbial-derived OM. Therefore, plant chemistry influenced soil OM turnover. Synthetic OM-clay complexes and soil mineral fractions were used to investigate lignin protection from chemical oxidation. Coating with dodecanoic acid protected lignin from chemical oxidation, and overlying vegetation determined the relative resistance of lignin phenols in clay-size fractions from chemical oxidation. Therefore, additional protection from chemical oxidation may be attributed to OM composition and interactions between OM structures sorbed to clay minerals. Overall, these studies suggest that while association with minerals is important, OM turnover is also influenced by vegetation, and protection through association with clay minerals was modified by OM structure composition. As well, OM-OM interaction is a potential mechanism that protects soil OM from degradation.

Soil organic matter (OM) is a complex mixture of compounds, mainly derived from plants and microbes at various states of decay. It is part of the global carbon cycle and is important for maintaining soil quality. OM protection is mainly attributed to its association with minerals. However, clay minerals preferentially sorb specific OM structures, and clay sorption sites become saturated as OM concentrations increase. Therefore, it is important to examine how OM structures influence their association with soil minerals, and to characterize other protection mechanisms. Several techniques, which provide complementary information, were combined to investigate OM composition: Biomarker (lignin phenol, cutin-OH acid, and lipid) analysis, using gas chromatography/mass spectrometry; solid-state 13C nuclear magnetic resonance (NMR) spectroscopy; and an emerging method, solution-state 1H NMR spectroscopy. OM composition of sand-, silt-, clay-size, and light fractions of Canadian soils were compared. It was found that microbial-derived and aliphatic structures accumulated in clay-size fractions, and lignin phenols in silt-size fractions may be protected from further oxidation. Therefore, OM protection through association with minerals may be structure-specific. OM in soils amended with maize leaves, stems, and roots from a biodegradation study were also examined. Over time, lignin phenol composition, and oxidation; and aliphatic structure contribution changed less in soils amended with leaves compared to soils amended with stems and roots. Compared to soils amended with leaves and stems, amendment with roots may have promoted the more efficient formation of microbial-derived OM. Therefore, plant chemistry influenced soil OM turnover. Synthetic OM-clay complexes and soil mineral fractions were used to investigate lignin protection from chemical oxidation. Coating with dodecanoic acid protected lignin from chemical oxidation, and overlying vegetation determined the relative resistance of lignin phenols in clay-size fractions from chemical oxidation. Therefore, additional protection from chemical oxidation may be attributed to OM composition and interactions between OM structures sorbed to clay minerals. Overall, these studies suggest that while association with minerals is important, OM turnover is also influenced by vegetation, and protection through association with clay minerals was modified by OM structure composition. As well, OM-OM interaction is a potential mechanism that protects soil OM from degradation.