Dissertations / Theses on the topic 'Diet – Environmental aspects'
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1
Li, Ying Chun 1972. "Modeling the Inuit diet to minimize contaminant while maintaining nutrient intakes." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101605.
Full textAbstract:
The Arctic environment is changing rapidly. The purposes of this study were: (1) to predict the possible changes of diet composition and the subsequent changes in nutrient intakes as a result of environmental changes; (2) to explore the possibility of minimizing the contaminant exposure while maintaining the energy and nutrient intakes using liner modeling. It was found that a decrease of 10% or 50% of caribou or ringed seal will result in decreases for many key nutrients such as protein, zinc, and iron. It is theoretically feasible to minimize each contaminant intake while maintaining energy and nutrients at the levels of the CINE dietary survey in 2000 for Inuit in the Inuvialuit, Kitikmeot, and Kivalliq regions. However, it is theoretically infeasible for Inuit in the Labrador and Baffin regions under other hypothetical conditions. The modeling results would be useful for Inuit to make informed food choice decisions.
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Janoco, Martin. "Evaluating the sustainability of vegetarian, vegan, and New Nordic diets in Sweden : Combining environmental and nutritional aspects." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260278.
Full textAbstract:
Changing the western dietary pattern toward a healthier diet with reduced intake of animal foods is a commonly recognized strategy in the ongoing effort for global sustainability. Since animal foods tend to have a high environmental impact, vegetarian diets are often suggested as an ecological alternative to the typical Western diet. The low sum of environmental impacts, however, does not on its own necessarily translate to a sustainable diet. Sustainability encompasses many other aspects, such as nutritional adequacy, affordability, and cultural acceptability. As regards the elimination of animal foods in particular, health-related aspects ought to be considered since some nutrients are supplied primarily via animal products which may lead to nutritional deficiencies and potential negative health effects in the long term. Furthermore, since the main function of diets is the supply of (adequate) nutrition, the environmental impacts of diets ought to be compared in light of their nutritional quality. In this project the environmental impact on climate change, land use, blue water footprint, and biodiversity damage potential of four diets is assessed, along with their nutritional adequacy and financial cost. The four assessed diets are: an average Swedish diet, New Nordic diet, vegetarian diet, and vegan diet. The environmental impacts are normalized with a nutritient-rich diet score (NRD) to compare the impacts of diets in relation to their nutritional quality. The vegan diet, followed by the vegetarian diet, resulted in the lowest overall impact with the exception of blue water footprint, however, the normalization with NRD score lessened the relative differences between the New Nordic, vegetarian, and vegan diet. Furthermore, the nutritional assessment showed a potentially unsustainable intake of vitamin D in vegetarians and vit. D and B12 in vegans, which is not properly reflected in the nutritional quality score. Nevertheless, the use of the nutritional score is fairly simple and provides opportunity for linking the health-related aspect of diets to their environmental impact. Joined with indicators on other sustainability aspects, such as the economic, this method can offer a more holistic picture of the sustainability of diets.Att ändra det västerländska kostmönstret mot en hälsosammare diet med minskat intag av animaliska livsmedel är en allmänt erkänd strategi i den pågående ansträngningen för global hållbarhet. Eftersom djurfoder tenderar att ha stor miljöpåverkan, är vegetariska dieter ofta föreslagna som ett ekologiskt alternativ till den typiska västerländska kosten. Den låga summan av miljöpåverkan innebär emellertid inte nödvändigtvis att det är en hållbar diet. Hållbarhet omfattar många andra aspekter, såsom näringskrav, överkomlighet och kulturell acceptans. När det gäller avskaffandet av animaliska livsmedel bör i synnerhet hälsorelaterade aspekter beaktas eftersom vissa näringsämnen levereras primärt via animaliska produkter vilket kan leda till näringsbrist och potentiellt negativa hälsoeffekter på lång sikt. Eftersom dietens huvudsakliga funktion är tillförseln av (tillräcklig) näring, borde miljöpåverkan av dieter jämföras med hänsyn till deras näringskvalitet. I detta projekt bedöms miljöpåverkan med avseende på klimatförändringar, markanvändning, blått blåvattenavtryck och biologisk mångfaldskador för fyra dieter tillsammans med deras näringsbehov och ekonomiska kostnader. De fyra bedömda kostvanorna är: en genomsnittlig svensk diet, ny nordisk kost, vegetarisk kost och vegansk kost. Miljöpåverkan normaliseras med ett näringsrikt diettvärde (NRD) för att jämföra effekterna av dieter i förhållande till deras näringskvalitet. Vegansk diet, följt av vegetarisk kost, resulterade i den lägsta övergripande effekten, med undantag för blå vattenavtryck, men normaliseringen med NRD-poäng minskade de relativa skillnaderna mellan den nya nordiska, vegetariska och veganska dieterna. Vidare visade näringsvärderingen ett potentiellt ohållbart intag av vitamin D för vegetarianer och vit. D och B12 för veganer, vilket inte korrekt återspeglas I det näringsmässiga kvalitetsresultatet. Ändå är användningen av näringsvärdet ganska enkelt och ger möjlighet att koppla den hälsorelaterade aspekten av dieter till deras miljöpåverkan. Genom att kombinera indikatorer för andra hållbarhetsaspekter, såsom den ekonomiska, kan denna metod erbjuda en mer holistisk bild av dieters hållbarhet.
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Ostertag, Sonja. "Estimated dietary exposure to perfluorinated compounds in Canada." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112549.
Full textAbstract:
Perfluorinated carboxylates (PFCAs), sulfonates (PFSs) and perfluoroalkylsulfonamides (PFOSAs) have been detected in whole blood and serum of non-occupationally exposed humans, yet sources of exposure have not been fully elucidated. The objectives of this study were to estimate dietary exposure to perfluorooctane sulfonate (PFOS), PFCAs (C7--C 11) and fluorotelomer unsaturated carboxylates (FTUCAs) for the general Canadian and Inuit populations prior to the phase-out of perfluorooctyl-sulfonyl production by 3M and voluntary reductions in PFOA emissions under the PFOA stewardship program. PFCs were measured in 65 archived composite food samples prepared for the 1998 Canadian Total Diet Study (TDS) and 68 archived traditional foods from Nunavut using a newly developed methanol extraction combined with a solid phase extraction clean up. Dietary exposure was estimated using food intake data available from studies carried out between 1997 and 1998 in southern Canada and Nunavut.PFCs were detected in eight composite food samples from the Canadian TDS and in 61 traditional food samples. Elevated concentrations of PFCs were found in caribou liver (6.2+/-5.5 ng/g), ringed seal liver (7.7, 10.2 ng/g), polar bear meat (7.0 ng/g), beluga meat (7.0, 5.8 ng/g), luncheon meats (5.02 ng/g), cookies (2.7 ng/g), processed cheese (2.1 ng/g) and peppers (1.8 ng/g). Low levels of total PFCs (<1.5 ng/g) were measured in 41 traditional foods including: meat (caribou, ptarmigan, snow goose, bearded seal, walrus, black duck), berries, and fish (lake trout, arctic char). PFCs were not detected in beverages, unprocessed meats, breads, cereals and fruits from the TDS composite samples analyzed.
The ranges of estimated daily exposure to PFCs were between 2 and 59 ng-person-1 and 210 to 610 ng-person-1 for average Canadians and Inuit in Nunavut respectively. There were no statistically significant differences in mean PFC exposure levels for different age and gender groups in the general Canadian population. Inuit men in the 41 to 60 year old age group had statistically significantly higher estimated daily exposure to PFCs (p<0.05) than younger men and women from the same age group. This higher exposure was associated with the consumption of beluga muktuk, caribou liver and bearded seal intestine.
Traditional foods contributed a higher percentage to PFC exposure than market foods in all age and gender groups for the Inuit population. In general, caribou meat, arctic char meat and cookies contributed most to dietary exposure for Inuit, with caribou flesh contributing 43 to 75 percent to daily PFC dietary exposure. Dietary exposure for the general Canadian population was associated with the consumption of cakes and cookies, processed cheese, and regular cheese.
Levels of dietary exposure to PFCs estimated in these studies do not pose any significant health risk to either population based on current toxicological information.
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MacIntosh, John 1967. "The influence of heavy metals on the diet changes of Neoperla (Plecoptera) in the northwest Miramichi River, New Brunswick /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79038.
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In the summers 1997, 1998 and 1999, over 100 aquatic invertebrate kick samples were collected in the Northwest Miramichi River of northeastern New Brunswick to examine the effects of chronic heavy metal exposure on the aquatic predatory Plecoptera community. In the group of predators, Neoperla (Plecoptera) was numerically dominant and gut content identifications were used to determine food chain and life cycle stages. Neoperla diet analysis indicated the Chironomidae (Diptera) as the dominant prey with predation upon Trichoptera and Ephemeroptera influenced by the life cycle stage of the predator. Gut content totals were analysed for predatory diet changes due to heavy metal contamination exposure. The Neoperla community indicated a prey shift from a Chironomidae based diet to one including a higher percentage of Ephemeroptera and Trichoptera earlier in the predators life history when compared with upstream control sites. Neoperla diets maintained their shift from the control station diets as the downstream movement of heavy metal contaminated water mixed and dissipated within the study area.
5
Waddington, Kris Ian. "Diet and trophic role of western rock lobsters (Panulirus cygnus George) in temperate Western Australian deep-coastal ecosystems (35-60m)." University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0035.
Full textAbstract:
[Truncated abstract] Removal of consumers through fishing has been shown to influence ecosystem structure and function by changing the biomass and composition of organisms occupying lower trophic levels. The western rock lobster (Panurilus cygnus), an abundant consumer along the temperate west coast of Australia, forms the basis of Australia's largest single species fishery, with catches frequently exceeding 11000 tonnes annually. Despite their high abundance and commercial importance, the diet and trophic role of adult lobster populations in deep-coastal-ecosystems (35-60 m) remains unknown. An understanding of the diet and trophic role of lobsters in these ecosystems is a key component of the assessment of ecosystem effects of the western rock lobster fishery. This study uses gut content and stable isotope analyses to determine the diet and trophic role of lobsters in deep-coastal ecosystems. Dietary analysis indicated adult lobsters in deep-coastal ecosystems were primarily carnivorous with diet reflecting food available on the benthos. Gut content analyses indicate crabs (62 %) and amphipods/isopods (~10 %) are the most important lobster dietary sources. Stable isotope analysis indicates natural diet of lobsters in deep coastal ecosystems is dominated by amphipods/isopods (contributing up to ~50 %) and crabs (to ~75 %), with bivalves/gastropods, red algae and sponges of lesser importance (<10 % of diet each). Diet of lobsters in deep-coastal ecosystems differed from that reported for lobsters inhabiting shallow water ecosystems in this region, reflecting differences in food availability and food choice between these ecosystems. Bait from the fishery was also determined (by stable isotope analyses) to be a significant dietary component of lobsters in deep-coastal ecosystems, contributing between 10 and 80 % of lobster food requirements at some study locations. '...' Given observed effects of organic matter addition in trawl fisheries, and also associated with aquaculture, bait addition is likely to have implications for processes occurring within deep-coastal ecosystems in this region, particularly given its oligotrophic status, most likely by increasing the food available to scavenging species. Removal of lobsters from deep-coastal ecosystems may affect the composition and abundance of lobster prey communities through a reduction in predation pressure. Such effects have been demonstrated for other spiny lobster species. These effects are typically most observable amongst common prey taxa which in other studies have been commonly herbivores. In deep-coastal ecosystems, crabs and amphipods/isopods are the most common prey taxa and most likely to be effected. The ecosystem-impacts of top-down control of non-herbivorous prey species is unknown and constrains the inferences possible from this study. However, the establishment of 'no-take' areas in deep-coastal ecosystems would allow the ecosystem effects of lobster removal to be further assessed in these deep-coastal ecosystems. While data from the current study did not allow the ecosystem effects of lobster removal to be properly assessed, this study provided information regarding the ecology of western rock lobsters in previously unstudied ecosystems.
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Kim, Christine Ji-Hyun. "Assessment of cadmium intake from the consumption of traditional food in Fort Resolution, Northwest Territories." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23902.
Full textAbstract:
The aim of this study was to investigate the cadmium (Cd) exposure level from traditional food in Fort Resolution, Northwest Territories. Cd concentration in the liver and kidney of caribou and moose exceeded the action level (1 $ mu$g/g) established by Agriculture Canada, but the frequencies of consumption of these foods were relatively low. Cd intakes from traditional food ranged from 0.01 to 1713 $ mu$g/day/person. Average Cd intakes from traditional food were estimated to be 10% and 6% of the Provisional Tolerable Weekly Intake (PTWI), 7 $ mu$g/kg body weight/person, for women and men, respectively. The major contributors to the total Cd intake on a population basis were moose liver for women, and flesh of moose and caribou for men. The average Cd inhaled from cigarette smoking was 21.1 $ pm$ 9.1 $ mu$g/day/person. Total Cd intakes from traditional food and smoking were estimated to be 24% and 20% of the PTWI for women and men, respectively. The total Cd intakes of smokers and nonsmokers were significantly different (p $<$ 0.001). The total Cd intake via market and traditional food, and cigarette smoking was 246.4 $ mu$g/week which was lower than the PTWI, 500 $ mu$g/week. Another objective of this study was to investigate an effect of food preparation on Cd speciation in food. (Abstract shortened by UMI.)
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Chitongo, Rumbidzai. "Antibiotics in the Diep River and potential abatement using grape slurry waste." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2575.
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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2017.Pharmaceuticals have found extensive application in human health management. They are released into the environment through urine, excreta and inappropriate disposal methods. Residues of pharmaceutical products have been reported to show toxic consequences in some freshwater and marine organisms. Antibiotics are one of the most important groups of common human pharmaceuticals widely in use as prescribed and non-prescribed drugs. Antibiotics and their metabolites have been quantitated in water and found in trace levels. But even at such low concentrations they can maintain high biological activities with potential adverse effects on humans and animals. Unfortunately, many pharmaceutical compounds are resistant to breakdown in the environment, hence they have tendency for environmental magnification, since they are designed to be biologically active. Therefore, there is need to evaluate their environmental levels and their possible abatement methods using simple, cheap and low cost techniques, in order to avert their potential toxic consequences. In this research, a cost effective, robust, selective and rugged method for the analysis of antibiotics in water samples using liquid chromatography was developed, and used for monitoring levels of the selected antibiotics in Diep River. Also, an effective remediation procedure for these contaminants in water was developed using activated carbon produced from grape slurry waste.
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Chu, Fong Lam 1976. "Total toxaphene and specific congeners in Inuit foods and diets." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33732.
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Elevated toxaphene levels have been reported in the biota of the Arctic. The purpose of this study is to measure total toxaphene levels in food samples commonly consumed by the Canadian Inuit and study the relationship between concentrations of total toxaphene and individual congeners. A total of 127 Inuit food samples were collected for toxaphene analysis. Total toxaphene and the specific toxaphene congeners including Parlar #26, #40/41, #42, #44, #50 and #62 were detected in the food samples. Total toxaphene concentrations ranged from 13 to 2800 ng/g and various congener concentrations ranged from 0 to 610 ng/g. Concentrations of total toxaphene were strongly correlated with congener concentration in marine mammals and weaker in fish. The sum of congeners Parlar #26, #50 and #62 accounted for 0--15% of total toxaphene in fish and 0--66% in marine mammals. Regression models were used to estimate total toxaphene based on individual or combinations of congener concentrations. Dietary intake was estimated to be 1.07 and 0.78 mug/kg body weight per day in Chesterfield Inlet and Igloolik. Our results show that there is no general conversion factor that can be used to estimate total toxaphene concentrations based on congener measurements.
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Cochlan, William Patrick. "Nitrogen uptake by marine phytoplankton : the effects of irradiance, nitrogen supply and diel periodicity." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/30628.
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Diel patterns of nitrogen (NO₃⁻, NH₄⁺, urea) uptake were
investigated in natural assemblages of phytoplankton from
neritic and oceanic environments off the coast of British
Columbia. This is the first study to report nitrogen uptake
rates and extensive measurements of ambient NH₄⁺ and urea
concentrations in these waters. Calculated rates of N uptake, 15
based on ¹⁵N incorporation into particulate matter during time course experiments, were maximal during the day and minimal at night. Besides the obvious effects of irradiance, the amplitude of the periodicity in uptake rate was influenced by phytoplankton community composition, ambient nitrogen concentration, forms of nitrogen available, and depth of sampling. Uptake of nitrogen during the night and in artificial darkness were measurable proportions of daytime and light uptake rates, with the importance of dark uptake generally increasing with increasing N limitation. This is the first study of diel urea uptake by marine phytoplankton in the field. The ratios of dark to light urea uptake over a diel cycle were more similar to those of NO₃⁻than those of the other reduced N form, NH₄⁺.
Rates of NO₆⁻ and urea uptake by phytoplankton in the shallow and deep chlorophyll layers of the Strait of Georgia were measured over a gradient of irradiances and results of these experiments could be fitted with a hyperbolic function similar to the Michaelis-Menten equation. Half-saturation constants (KLT) for light-dependent uptake of urea and NO₃⁻
ranged from 0 to 14% of the surface irradiance and dark uptake was a variable, but often substantial (> 50%) portion of the total (light + dark) uptake.
The uptake response of nitrate-replete and -starved populations of the picoflagellate, Micromonas pusilla (Butch.) Manton et Parke, to urea, NH₄⁺ and NO₃⁻ perturbations was determined by both ¹⁵N accumulation and nutrient disappearance
from the culture medium. Maximum specific uptake rates (Vmax) of NH₄⁺ were 0.13 h⁻¹, more than 2 times the Vmax of NO₃⁻ or urea (ca. 0.05 h⁻¹). The half-saturation constants (Ks) for urea, NH₄⁺ and NO₃⁻ were within ± 0.1 µg-at N•L⁻¹ of each other; the average value of 0.41 µg-at. N•L⁻¹ is within the range reported for small, oceanic diatoms. NO₃⁻ uptake was completely inhibited following NH₄⁺ addition (1-10 µg-at. N•L⁻¹), whereas urea addition resulted in only a 28% reduction in NO3- uptake. Starved cultures of M. pusilla exhibited variable uptake of NH₄⁺ and urea as a function of time, with an initial "surge" uptake response. This is the first laboratory study of N uptake by an eucaroyotic picoplankter and demonstrates that many of the transient uptake responses reported for diatoms, with which it competes in the field, are common to this picoplankter.
Diel periodicity of nitrogen uptake and assimilation were measured in N-replete batch cultures of M. pusilla and also in N-limited cyclostat cultures (14L:10D) at three growth rates corresponding to ca. 75, 50 and 25% of it's maximal growth rate. Nitrate uptake was continuous and independent of the
L:D cycle in the cyclostat cultures at the lowest dilution rate, but NO₃⁻ uptake rates exhibited pronounced periodicity in the batch and higher dilution rate cultures, a response similar to that seen in previous studies of cyclostat cultures of some diatoms. Diel patterns in cell division, mean cell volume, potential uptake rates and internal pools of NO₃⁻ were also observed and are discussed with respect to the nutritional status of the cells. The effect of irradiance on the uptake of NH₄⁺ and NO₃⁻ by M. pusilla was also described by Michaelis-Menten kinetics; with increasing N limitation the importance of light for nitrogen uptake decreased and dark uptake increased from 5-20% to 21-39% of NO₃⁻ and NH₄⁺ uptake rates, respectively, at saturating irradiance.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Saavedra, Aracelli Pinelli. "Vitamin E and vitamin C supplementation of sows in a hot environment : effects on reproductive performance, piglet tissue levels and aspects of immune status." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369542.
Full textAbstract:
Summer and winter experiments were carried out to investigate the effects of dietary supplementation with vitamin E and vitamin C of sows in hot environments on reproductive performance, placenta transfer, piglet tissue vitamin E content and some indicators of immune status of sows and their litters. In summer, sows were given the following treatment diets: control, vitamin C 1g/day, vitamin C 10g/day, vitamin E 200 mg/kg feed, vitamin E 400 mg/kg fed, and combined vitamins (vitamin E 200 mg/kg feed + vitamin C 1 g/day). In winter, sows were given the following treatment diets: control, vitamin C 10g/day, vitamin E 500 mg/kg feed, combined vitamins (vitamin E 500 mg/kg/feed + vitamin C 10g/day). Data show that vitamin E had an effect on growth, but not on reproductive performance. Placental vitamin E concentrations were low but increased with dietary vitamin E supplementation. Vitamin E supplementation resulted in an increase in vitamin E content of sow plasma, piglet serum, colostrum and milk and piglet tissues. Supplementation with vitamin E and vitamin C had no consistent effect on parvovirus titer in sows. The relationship between sow plasma vitamin C and vitamin E concentrations and lymphocyte proliferation was not clear. Total Igs and IgG concentrations in piglet serum at weaning were significantly increased by the combined vitamin treatments. However, vitamins supplementation did not appear to have any effect in IgG colostrum. IgA concentration in milk was increased by the high level of vitamin E supplemented in the summer but not in the winter experiment.
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Borucki, Castro Sylvia Irene. "Altering electrolyte balance of diets for lactating dairy cows to reduce phosphorus excretion to the environment." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=78324.
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The study was designed to test the hypothesis that P excretion in manure of dairy cattle could be reduced by manipulating electrolyte balance of the diet. Feces was the main route of P excretion, but fecal P was not affected by dietary cation-anion (DCAB) (P > 0.05). Plasma concentration of P tended (P < 0.10) to be higher at lower DCAB levels, implying that DCAB may have influenced P homeostasis. The overall P balance was not affected by the different DCAB levels. The range of DCAB where both P excretion and animal performance could be optimised is very narrow (+250 to +350 mEq/kg DM), so using DCAB to control P excretion in dairy cattle requires caution. (Abstract shortened by UMI.)
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Fagbayigbo, Bamidele Oladapo. "Perfluorooctane acid (PFOA) and perfluorooctane sulfonate (PFOS) in the Plankenburg (Stellenbosch) and Diep (Milnerton) Rivers, and potential remediation using vitis vinifera leaf litter." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2668.
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Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2017.This study represents the first monitoring campaign to assess the seasonal trend of nine perfluorinated compounds (PFCs) in surface water and sediment from the Plankenburg and Diep Rivers in the Western Cape, South Africa. An analytical protocol was developed and validated for qualitative and quantitative routine determination of nine perfluorinated compounds (PFCs), in water and sediment samples using Ultra performance liquid chromatography-mass spectrometry quadrupole time of flight (UPLC-QTOF-MS). This method was applied to determine levels of PFOA and PFOS in environmental samples. Samples were collected along the Diep (Milnerton) and Plankenburg (Stellenbosch) Rivers respectively. Samples were pre-treated, cleaned-up and extracted using solid-phase extraction (SPE) procedures with hydrophilic-lipophilic balance (HLB) C-18 cartridges. Seasonal variation and distribution of PFCs in surface water and sediment was also investigated. Levels of PFCs were monitored in four seasons (summer, autumn, winter and spring) to establish their trend in the environment. The removal of PFOA and PFOS from aqueous solutions using agro-waste biomass of Vitis vinifera (grape) leaf litter was also studied. Activated carbons were produced from the biomass and chemical activation achieved with phosphoric acid (H3PO4) and potassium hydroxide (KOH) for the modification of the carbons’ (AC-H3PO4 and AC-KOH respectively). Activated carbons were characterized using Fourier Transform infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Brunauer- Emmett-Teller (BET) in order to understand the removal mechanisms of the contaminants by activated carbons. The effects of solution concentration, pH, adsorbent dosage, contact time, and the temperature were optimized for evaluation of the removal efficiency of the activated carbons. Adsorption isotherm models were used to analyze the equilibrium data obtained and kinetic models were applied to study sorption mechanisms. A fixed bed column study was conducted using: AC-H3PO4 adsorbent. Experimental parameters such as initial concentration of the solution, column bed height, flow rate and initial concentrations of the influent were optimized to establish the best adsorption efficiency parameters of the column system. Breakthrough curve and exhaustion time were predicted using Adam-Bohart, Yoon-Nelson, and Thomas models for the fixed bed column under varying experimental conditions.
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Wickramasinghe, Kremlin. "Quantifying the impact of policies addressing sustainable and healthy diets." Thesis, University of Oxford, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.711872.
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Mudumbi, John-Baptist Nzukizi. "Perfluorooctane sulfonate and perfluorooctanoate contamination of riparian wetlands of the Eerste, Diep and Salt Rivers." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2017.
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Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2012.Perfluorinated compounds (PFCs), in particular perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) have been found in aquatic environments throughout the world. Recent studies have reported that owing to their bioaccumulative nature, PFCs may also be present in various water sources, resulting in human and wild-life exposure. Although, these PFCs usually occur at low concentration levels, their presence in the environment has nevertheless been a concern in both developed and developing countries, since water remains an important natural resource for most living species. Water and sediment from rivers are one of the matrices in which PFC contamination is studied, since rivers receive water from various sources. However, limited studies have been conducted in South Africa on PFC contamination of river water and sediments. Although PFCs are sometimes unintentionally released into the environment, the concentration and type of PFCs that contaminate water sources vary among countries and depend on the types of industry releasing them into the environment, suggesting that PFC contamination patterns can be expected to differ from country to country, with PFOA and PFOS being the predominant perfluorinated contaminants. The aim of this study was therefore to determine the concentration of PFOS and PFOA in riparian wetlands of the Western Cape, focusing on the Eerste, Diep and Salt rivers, which are the primary rivers in the largest catchment areas of the Western Cape, South Africa.
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Erasmus, Deborah Vivian. "Metal bioaccumulation, membrane integrity and chlorophyll content in the aquatic macrophyte ceratophyllum demersum from the Diep River, Western Cape." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2027.
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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2012.The Diep River is approximately 80 km in length and runs through agricultural land and urban parts of greater Cape Town, South Africa before entering the Atlantic Ocean, via an estuary. Generally, metal pollution in South African rivers is not well documented and using plants to monitor metal bioaccumulation is even less documented. The aim of this study was to investigate aluminium, iron, copper and zinc metal pollution in the Diep River and bioaccumulation of these metals in the leaves and stems of the submerged macrophyte Ceratophyllum demersum L. Furthermore, the effects of bioaccumulated metals on membrane integrity and chlorophyll content of these plants were investigated. Site 1 was situated in the upper reaches of the river adjacent to agricultural land, while site 2 was in an urban area, where industrial activities predominate. C. demersum (from an uncontaminated source) were introduced into the river at the two sites and compared with one another on a fortnightly basis over a 12 week period. Plants at site 2 were also compared to existing plants that were naturally growing at the site. Comparisons were also made between leaves and stems of the plants, to establish the organ of preference regarding metal accumulation and storage. Samples were digested with nitric acid and an ICP-MS was used to analyse metal concentrations in the water, sediment and plants. Chlorophyll extraction was done using dimethyl sulphoxide (DMSO) and the absorbance values determined using a spectrophotometer. Chlorophyll a, chlorophyll b and total chlorophyll contents were recorded and compared. Cell membrane integrity was determined by leaving plants for 24 hours in deionised water and measuring electrical conductivity and solutes (sodium, calcium, potassium and magnesium) before and after placement of the plants.
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Gore, Asa M. "The effect of soybean oil in starter diets on nursery air quality and performance of weanling pigs." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53072.
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Crossbred pigs 3 to 4 weeks of age were randomly assigned from outcome groups based on weight and sex to one of four dietary treatments either with or without added soybean oil or hulls. Nursery air quality was evaluated by measuring the concentrations of ammonia, carbon dioxide, settled dust, suspended particle size, and by microbiologically culturing air samples. Weekly performance data was also collected.
ADG was unaffected by dietary treatment. ADFI was increased when soybean hulls were added to the ration with the difference being significant in trials 1 and 2 and over-all. Adding soybean oil to the ration produced slightly lower feed intakes over all trials but was not significant. Rations with added soybean oil reduced F/G, whereas, the addition of soybean hulls increased F/G for over-all trials. The response to soybean oil was less when soybean hulls were added. A comparison of rations 1 and 4 showed only slight differences in ADG, ADFI and F/G. The addition of soybean oil resulted in a 47% reduction in settled dust for trials 1 and 2 combined, and a 45% reduction for trial 3. Mean bacterial colony counts for each week and over-all for trial 3 were lower when soybean oil was added to the ration. Ammonia and carbon dioxide concentrations were not affected by dietary treatment.
From the results of this experiment, the addition of soybean oil to starter diets improved nursery air quality and performance in some cases, however, gas concentrations were not different.Master of Science
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Ayeni, Olutoyosi Olaide. "An investigation into the effect of metals on chlorophyll content and photosynthesis activity of the wetland plant phragmites australis in the lower Diep River, Milnerton, Cape Town." Thesis, Cape Peninsula University of Technology, 2011. http://hdl.handle.net/20.500.11838/2016.
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Thesis (MTech (Environmental Management)))--Cape Peninsula University of Technology, 2011.A study involving a wetland plant, common reed (Phragmites australis L.) was carried out along the bank of the lower Diep River and the adjacent soil samples from four different sites (Milnerton Lagoon, Lower Estuary, Milnerton Bowling Club and Woodbridge Island), Cape Town, South Africa. The aim was to determine the extent of metal contamination and its impact on physiological indices. Results showed that among the metals evaluated, AI and Fe were consistently higher in all the soil samples (from both river bank and the adjacent soil) followed by Zn, Mn, Pb, Cu, Cd, Co, Cr and Ni. The concentrations of AI in the river banks ranged between 1214.1 - 3176 mg.kg-1 compared with the adjacent soils, where AI concentration ranged from 434.8 - 2445.4 mg.kq". The Fe concentrations from the river bank values ranged from 1136.4 - 4897.2 mg.kg-1 compared with Fe concentrations of the adjacent soil samples which ranged from 402.2 - 2459.8 mg.kg-1 . Generally, Zn ranged from 2.4 - 211.5 mq.kq"; Mn: 5.5 - 48.05 mg.kq': Pb: 0.97 - 71.7 mg.kq"; Cu: 0.3 - 45.9 mg.kq'; Cd: 0.0 - 9.3 mg.kq": Co: 0.2 - 2.7 mg.kq': Cr: 0.3 - 2.1 mg.kg-1 ; and Ni: 0.02 - 2.6 mg.kg-1. Overall, Ni had the lovest concentrations in the ecosystem. Results also showed that the abundance of metals from plant samples were in the order of AI > Pb > Cd > Co > Ni > Cr; and for micronutrients, Fe > Mn > Zn > Cu both in the shoots and roots sampled from all the sites investigated. The values of chlorophylls a, b and total chlorophyll as well as photosynthesis were significantly higher in the P. australis plant samples and from the adjacent soil compared with those from the river bank. These results suggest that contamination of soils and wetland ecosystem by metals over and above plant requirements may affect the chlorophyll and photosynthesis rate of the plant thereby undermining the physiological functioning of plants growing along river systems.
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Eagan, April Hurst. "Heritage and Health: A Political-Economic Analysis of the Foodways of the Paiute Indian Tribe of Utah and the Bishop Paiute Tribe." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/685.
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Funded by Nellis Air Force Base (NAFB), my thesis research and analysis examined Native American knowledge of heritage foods and how diminished access to food resources has affected Native American identity and health. NAFB manages the Nevada Test and Training Range (NTTR), land and air space in southern Nevada, which includes Native American ancestral lands. During a research period of 3 months in the spring/summer of 2012, I interviewed members of Native American nations culturally affiliated with ancestral lands on the NTTR, the Paiute Indian Tribe of Utah (PITU) and the Bishop Paiute Tribe. My research included participant observation and 31 interviews with tribal members considered knowledge holders by tribal leaders. In dialogue with the literature of the anthropology of food, political economy, and Critical Medical Anthropology, my analysis focused on the role of heritage foods in everyday consumption, taking into account the economic, social, environmental, and political factors influencing heritage foods access and diet. My work explored the effects of structural forces and rapid changes in diet and social conditions on Native American health. I found shifts in concepts of food-related identity across ethnic groups, tribes, ages, and genders. I also found evidence of collective efforts to improve diet-related health at tribal and community levels. Through the applied aspects of my research, participants and their families had the opportunity to share recipes and food dishes containing heritage foods as a way to promote human health and knowledge transmission.
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Ramsey, Sheryll Elaine. "The effect of selected health, environmental, and socioeconomic variables on energy and protein intake in the Dominican Republic." 1985. http://hdl.handle.net/2097/27523.
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Madad, Leila. "The interaction of intrauterine environment and diet on the pathogenesis of Type 2 Diabetes." Master's thesis, 2010. http://hdl.handle.net/1885/150619.
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Introduction: Prenatal environmental factors such as intrauterine growth retardation (IDGR), as well as postnatal factors such as over-nutrition and sedentary lifestyle contribute to the development of type 2 diabetes (T2D) in predisposed individuals. The aim of this study was to determine in a rat model whether IDGR and high fat lipogenic diet interact in T2D pathogenesis. Methods: A previously described surgical model ((bilateral uterine artery ligation (BDAL)) of IDGR Sprague-Dawley rats with sham-operated controls was used. Male and female IDGR and sham pups were fed high fat or chow-diets from weaning. Serial measurements of body weight and serum variables including blood glucose, free fatty acids and triglyceride were taken. Intraperitoneal glucose tolerance tests including insulin response measurements were performed at 13 and 23 weeks of age. At 24 weeks of age, the rats were euthanased and pancreases were harvested. Pancreases were assessed histologically with haematoxylin and eosin staining for islet morphology, perl staining for iron, trichrome staining for collagen. Sections were also immunostained for insulin. Results: The BDAL surgery resulted in IDGR pup weights that were approximately 25% less that the sham pup weights. Thus, the BDAL procedure was effective in producing moderately severe intrauterine growth restriction. The chow-fed IDGR rats developed an abnormal metabolic phenotype, but this was mild compared to the previously reported IDGR model. The chow-fed IDGR rats did not develop overweight or diabetes, but did develop fed-state hypertriglyceridaemia (female only) and fasting hyperlipacidaemia (male only) as well as hyperinsulinaemia (evident at 23 weeks of age in male rats with a trend for this evident in female rats). Control sham rats on high fat-diet developed hyperglycaemia, fed-state hyperlipacidaemia, fasting and fed-state hypertriglyceridaemia and mildly impaired glucose tolerance with evidence of marked post-glucose load hyperinsulinaemia. Unexpectedly, the high fat-fed IUGR rats were protected against excessive weight gain (most evident in female rats), nonfasting hyperglycaemia and glucose intolerance (evident in female rats only). IUGR rats on the HF diets, however, had higher non-fasting triglyceride levels and had accentuated hyperinsulinaemia in response to a glucose load at 23 weeks of age. Thus, IUGR and high fat-diet most likely caused a greater degree of hyperinsulinaemia. Despite mild effects of IUGR on the metabolic phenotype of the rats, the histological analyses of the pancreases showed major changes in male rats. Two of four chow-fed IUGR had evidence of multiple large disorganized islets; where four of five high fat fed IUGR rats had these disorganized islets. No sham rat pancreases had any of these abnormal islets. Staining for iron showed marked peri-islet iron accumulation associated with these abnormal islets and staining for collagen showed marked islet fibrosis. The insulin immunohistochemistry confirmed the abnormal islet architecture. Conclusion: IUGR chow-fed rats did not develop T2D, which is at variance from previously reported studies. IUGR did alter the effects of high fat-diet on the metabolic phenotype causing more severe hypertriglyceridaemia and insulin resistance, but again diabetes did not develop. The Canberra IUGR rat, as opposed to the one previously reported, is capable of successful islet beta cell compensation. However, islet morphology was severely disturbed in the Canberra male IUGR rats that appeared worse with high fat feeding. The presence of increased iron staining associated with these abnormal islets may have pathophysiological significance. We postulate that genetic background and its effect on islet susceptibility to insults (intrauterine and post-natal) is an essential component in pathogenesis of T2D, explaining the differences between IUGR models.
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Walburger, Kenric. "The effects of timber harvest and herbivory on understory vegetation and composition of beef cattle diets on forested rangelands." Thesis, 2005. http://hdl.handle.net/1957/29756.
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Hale, V. Cody. "Beyond the paired-catchment approach : isotope tracing to illuminate stocks, flows, transit time, and scaling." Thesis, 2011. http://hdl.handle.net/1957/26625.
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This dissertation integrates a process-based hydrological investigation with an
ongoing paired-catchment study to better understand how forest harvest impacts
catchment function at multiple scales. We do this by addressing fundamental questions
related to the stocks, flows and transit times of water. Isotope tracers are used within a
top-down catchment intercomparison framework to investigate the role of geology in
controlling streamwater mean transit time and their scaling relationships with the
surrounding landscape. We found that streams draining catchments with permeable
bedrock geology at the Drift Creek watershed in the Oregon Coast Range had longer
mean transit times than catchments with poorly permeable bedrock at the HJ Andrews
Experimental Forest in the Oregon Cascades. We also found that differences in
permeability contrasts within the subsurface controlled whether mean transit time
scaled with indices of catchment topography (for the poorly permeable bedrock) or
with catchment area (for the permeable bedrock). We then investigated the process-reasons
for the observed differences in mean transit time ranges and scaling behavior
using a detailed, bottom-up approach to characterize subsurface water stores and
fluxes. We found that the mean transit times in catchments underlain by permeable
bedrock were influenced by multiple subsurface storage pools with different
groundwater ages, whereas storage in the poorly permeable catchments was limited to
the soil profile and that resulted in quick routing of excess water to the stream at the
soil bedrock interface, leading to mean transit times that were closely related to
flowpath lengths and gradients. Finally, we examined how and where forest trees
interacted with subsurface storage during the growing season using a forest
manipulation experiment, where we tested the null hypothesis that near-stream trees
alone influenced daily fluctuations in streamflow. We felled trees within this zone for
two 2.5 ha basins and combined this with isotopic tracing of tree xylem water to test if
water sources utilized by trees actively contributed to summer streamflow. We
rejected our null hypotheses and found that diel fluctuations in streamflow were not
generated exclusively in the near-stream zone. We were unable to link, isotopically,
the water sources trees were utilizing to water that was contributing to streamflow.
Our results provide new process-insights to how water is stored, extracted, and
discharged from our forested catchments in Western Oregon that will help better
explain how forest removal influences streamflow across multiple scales and
geological conditions.Graduation date: 2012
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Joseph, Rowena Yasmin. "A gestalt approach in using music with the emotionally traumatized child." Diss., 2004. http://hdl.handle.net/10500/1785.
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Many of the sources indicated in this work are classical and not updated due to the fact that the origins of Gestalt Philosophy are found in classical worksVerskeie van die geraadpleegde bronne in die literatuurhoofstukke verteenwoordig klassieke werke wat nie binne die erkende periode vir relevante wetenskaplike navorsing val nie. Die oorsprong van die Gestalt Filosofie wat in hierdie studie benut is, word in hierdie klassieke werke gevind en is ook in hierdie werke geraadpleeg
The Gestalt approach was used as the contextual framework to explore how music can be used as a therapeutic medium in the treatment of the emotionally traumatized child. Music as a sensory experience was used during the therapeutic process with each case study, to facilitate the child's process towards healing. The conceptual framework of music as a therapeutic medium was researched in depth to bring clarity to the influence it has on the emotional well-being of the child. The child who entered into therapy was selected according to specific criteria, with the experience of emotional trauma being priority. The researcher also studied the concept of emotional trauma in depth and the consequences it has on a child's overall functional ability. Music was used as an expressive technique during the therapeutic process with each child. The conclusion drawn from this study indicated that the gestalt approach can be applied effectively in using music as a therapeutic medium in the treatment of the emotionally traumatized child.
Die Gestalt benadering is gebruik in hierdie navorsing ten einde 'n kontekstuele raamwerk daar te stel waarbinne musiek as terapeutiese medium in die behandeling van emosionele trauma in kinders gebruik kon word. Musiek kan beskryf word as 'n sensoriese ervaring. Hierdie sensoriese ervaring is binne die terapeutiese proses toegepas ten einde die kind se herstelproses te fasiliteer. Die studie is binne die navorsingskonteks van gevallestudieprosedures gedoen. Musiek is binne die konseptuele raamwerk bestudeer en nagevors ten einde die terapeutiese waarde daarvan in diepte te ondersoek. Hierdie in-diepte ondersoek het aan die navorser 'n duidelike beeld gegee hoe dit toegepas kon word in terapie. Deur dit toe te pas in terapie is die invloed van musiek op die emosionele welsyn van die getraumatiseerde kind gedokumenteer. Die navorsingskriteria vir insluiting in die ondersoek was gegrond op die literatuurondersoek en het onder meer die belewing van trauma ingesluit. Die belewing van emosionele trauma en invloed op die kind se geheelfunksionering was dus 'n verdere eenheid van ontleding en is in diepte deur die navorser bestudeer. Musiek is dus gebruik as 'n ekspressiewe tegniek tydens die terapeutiese proses met elke gevallestudie. Die gevolgtrekking waartoe in hierdie studie gekom kon word is dat musiek binne die konteks van die gestalt benadering suksesvol in die hantering van emosionele trauma by die kind gebruik kan word.
Practical Theology
M.Diac. (Play Therapy)