Dissertations / Theses: 'Maternal nutrients'

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Regnault, Timothy Robert Hume, of Western Sydney Hawkesbury University, Faculty of Agriculture and Horticulture, and School of Agriculture and Rural Development. "Orchestrated partitioning of maternal nutrients during ovine pregnancy." THESIS_FAH_ARD_Regnault_T.xml, 1997. http://handle.uws.edu.au:8081/1959.7/15.

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Ovine placental lactogen (oPL) is postulated to be involved in the repartitioning of maternal nutrients during pregnancy, through its effect on insulin metabolism. Ovine pancreatic insulin responses to exogenous glucose are depressed during pregnancy and this depression becomes more pronounced as gestation advances. In addition, under the hormonal environment of rising oPL and growth hormone (oGH) concentrations, maternal whole body glucose irreversible loss (GIL) increases. The percentage of GIL accounted for by uterine glucose uptake also increases with advancing gestation and increasing litter size. Regression analysis of oPL concentration with glucose uterine uptake as a percentage of GIL, accounts for 39% of variation. Maternal oPL concentrations which increase with gestational age, were significantly greater in multiple bearing ewes and ewes subjected to reduced metabolisable energy (ME) intakes. It is postulated that through actions on pancreatic sensitivity, oPL plays a major role as a homeorhetic control during pregnancy. Elevated oPL concentrations were strongly associated with continually depressed pancreatic insulin secretory ability. The reduction in pancreatic sensitivity to glucose was not as a result of elevation in GH or non-esterified fatty acid (NEFA) concentrations. Muscle insulin receptor number and affinity were found to increase with increasing litter size, suggesting that pregnancy associated insulin resistance occurs predominantly in adipose tissue. During ovine pregnancy there is a specific stimulation of maternal gluconeogenesis. As gestation advances, an increasingly greater proportion of this glucose is partitioned to the gravid uterus. The development of insulin resistance, together with the suppression of pancreatic activity, ensures the preferential uptake of glucose by non-insulin dependent tissues over insulin dependent tissues. These activities favour uterine glucose uptake, decrease adipose glucose uptake, and also promote adipose mobilisation and hepatic gluconeogenesis, so as to meet the increasing energy requirement of pregnancy. It is postulated that through these effects on insulin secretion and associated adipose tissue mobilisation factors, oPL plays a major role in homeorhesis during pregnancy.
Doctor of Philosophy (PhD)

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Regnault, Timothy Robert Hume. "Orchestrated partitioning of maternal nutrients during ovine pregnancy." Thesis, View thesis View thesis, 1997. http://handle.uws.edu.au:8081/1959.7/15.

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Ovine placental lactogen (oPL) is postulated to be involved in the repartitioning of maternal nutrients during pregnancy, through its effect on insulin metabolism. Ovine pancreatic insulin responses to exogenous glucose are depressed during pregnancy and this depression becomes more pronounced as gestation advances. In addition, under the hormonal environment of rising oPL and growth hormone (oGH) concentrations, maternal whole body glucose irreversible loss (GIL) increases. The percentage of GIL accounted for by uterine glucose uptake also increases with advancing gestation and increasing litter size. Regression analysis of oPL concentration with glucose uterine uptake as a percentage of GIL, accounts for 39% of variation. Maternal oPL concentrations which increase with gestational age, were significantly greater in multiple bearing ewes and ewes subjected to reduced metabolisable energy (ME) intakes. It is postulated that through actions on pancreatic sensitivity, oPL plays a major role as a homeorhetic control during pregnancy. Elevated oPL concentrations were strongly associated with continually depressed pancreatic insulin secretory ability. The reduction in pancreatic sensitivity to glucose was not as a result of elevation in GH or non-esterified fatty acid (NEFA) concentrations. Muscle insulin receptor number and affinity were found to increase with increasing litter size, suggesting that pregnancy associated insulin resistance occurs predominantly in adipose tissue. During ovine pregnancy there is a specific stimulation of maternal gluconeogenesis. As gestation advances, an increasingly greater proportion of this glucose is partitioned to the gravid uterus. The development of insulin resistance, together with the suppression of pancreatic activity, ensures the preferential uptake of glucose by non-insulin dependent tissues over insulin dependent tissues. These activities favour uterine glucose uptake, decrease adipose glucose uptake, and also promote adipose mobilisation and hepatic gluconeogenesis, so as to meet the increasing energy requirement of pregnancy. It is postulated that through these effects on insulin secretion and associated adipose tissue mobilisation factors, oPL plays a major role in homeorhesis during pregnancy.

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Regnault, Timothy Robert Hume. "Orchestrated partitioning of maternal nutrients during ovine pregnancy /." View thesis View thesis, 1997. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030513.111110/index.html.

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Thesis (Ph. D. of Philosophy)--University of Western Sydney, Hawkesbury, 1997.
"A thesis submitted to the School of Agriculture and Rural Development, Faculty of Agriculture and Horticulture, University of Western Sydney Hawkesbury, in part fulfilment of the requirements for the Degree of Doctor of Philosophy." Includes bibliographical references (p. 236-267).

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Angiolini, Emily Jayne. "Regulation of supply and demand for maternal nutrients by imprinted genes in mouse." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608459.

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Martinez, Maria Isabel Vega. "Desenvolvimento e produção de material de referência certificado de folhas de cana-de-açúcar para avaliação da qualidade nutricional." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-09102018-110451/.

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A cana-de-açúcar e produtos derivados são de grande relevância econômica para o Brasil e vários outros países. Inúmeras variedades de cana-de-açúcar são cultivadas e novas variedades têm sido desenvolvidas para buscar ganhos de produtividade. Nesse sentido, são indispensáveis materiais de referência certificados (CRMs) para o controle da qualidade de sistemas de medição e validação de métodos, objetivando o estudo do estado nutricional das diferentes variedades de cana-de-açúcar, de modo a otimizar os procedimentos de fertilização e incrementar a produção. Contudo, segundo a base de dados internacional de materiais de referência certificados (COMAR) não existe um CRM que atenda adequadamente a avaliação do estado nutricional da cana-de-açúcar. Assim, este trabalho investigou a possibilidade de produção de um material de referência de folhas de cana-de-açúcar que supra essa demanda. O trabalho foi dividido em duas etapas principais: 1) estudo de variedades de cana-de-açúcar quanto à composição elementar e 2) desenvolvimento do material de referência. Doze variedades de cana-de-açúcar cultivadas no Estado de São de Paulo foram abrangidas no estudo: CTC2, CTC4, CTC11, CTC14, CTC15, CTC17, CTC20, IACSP955000, RB855156, RB965902, RB966928 e SP832847. As técnicas analíticas utilizadas para a avaliação foram a análise por ativação neutrônica instrumental (INAA) e a espectrometria de emissão óptica com plasma acoplado indutivamente (ICP OES), além do método de Kjeldahl para determinação de N. Em geral, os resultados mostraram macronutrientes em níveis adequados, enquanto, dentre os micronutrientes, Cu e Zn foram encontrados no limite crítico para quase todas as variedades estudadas. A seleção da variedade RB966928 para produção do material de referência candidato foi baseada nas características nutricionais para alta produtividade, nos menores valores de coeficientes de variação de amostragem em campo (CV<30%) e nas características agronômicas. A produção do material candidato foi realizada a partir de 90 kg de folhas, utilizando apenas 15 cm da parte central sem a nervura principal. Após diversos testes para determinar o melhor procedimento de preparo, as folhas foram liofilizadas, moídas e homogeneizadas, obtendo-se 410 frascos do material candidato contendo 20 g cada. A caracterização física mostrou umidade residual do material de 3,8 % e tamanho de partículas < 115 µm. Testes de homogeneidade dentro do frasco e entre frascos foram realizados utilizando INAA e método de Kjeldahl. Os resultados de fração de massa demonstraram a homogeneidade do material dentro de frascos para dezoito elementos, usando massas de 180 mg a 200 mg. Já a homogeneidade entre frascos foi comprovada para vinte elementos. Estudos de estabilidade a curto e a longo prazo demonstraram que o material manteve-se estável nas três condições avaliadas (40°C com umidade relativa a 100%, 20°C e -20°C). A caracterização química final do material foi realizada no National Institute of Standards and Technology (NIST), Estados Unidos, onde foram atribuídos valores para dezoito elementos com respectivas incertezas expandidas associadas: Al, Br, Ca, Ce, Cl, Co, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sc, Sm, Th e Zn. Além disso, foram atribuídos valores estimativos para Hf, N, P, Sb, Sr e V determinados pelo método de Kjeldahl e INAA
The sugarcane and derived products are of great economic importance for Brazil and several other countries. Many varieties of sugar cane are grown and new varieties have been developed to seek productivity gains. In this sense, certified reference materials (CRMs) are necessary for the quality control of measurement systems and validation of methods, aiming at the study of the nutritional status of the different sugarcane varieties for optimizing fertilization and increasing production. However, according to the international database of certified reference materials (COMAR) there is not a suitable CRM for the assessment of nutritional status of sugarcane. Thus, this work investigates the possibility of producing a reference material from leaves of sugarcane to fulfill such a demand. The work was divided into two main steps: 1) study of sugarcane varieties regarding elemental composition and 2) development of the reference material. Twelve varieties of sugarcane grown in the State of São Paulo were covered in the study: CTC2, CTC4, CTC11, CTC14, CTC15, CTC17, CTC20, IACSP955000, RB855156, RB965902, RB966928 and SP832847. The analytical techniques used for the assessment of composition were neutron activation analysis (NAA) and optical emission spectrometry with inductively coupled plasma (ICP OES), in addition to the Kjeldahl method for determination of N. In general, the results showed macronutrients in adequate levels, while, among the micronutrients, Cu and Zn were found in the critical limit for almost all the varieties studied. The selection of the variety RB966928 for producing the candidate reference material was based on the nutritional characteristics for high productivity, on the lower coefficients of variation of sampling in the field (RSD < 30%) and on the agronomic characteristics. The candidate material was produced from 90 kg of leaves, using only 15 cm from the central part without the main rib. After various tests for determining the best preparation procedure, the leaves were lyophilized, milled and homogenized, obtaining 410 bottles of the candidate material containing 20 g each. The physical characterization found residual moisture of 3.8 % and particle size < 115 µm. Homogeneity tests within and between bottles were performed using NAA and Kjeldahl method. The results confirmed the within bottle homogeneity of the material for all eighteen elements, using masses from 180 mg to 200 mg, while the homogeneity between bottles was confirmed for twenty elements. Stability studies in the short and the long term demonstrated that the material was stable in the three conditions used (40°C with a relative humidity of 100%, 20°C and 20°C). The final characterization of the candidate material was performed at NIST, National Institute of Standards and Technology, United States, where values were assigned for eighteen elements with respective expanded uncertainties: Al, Br, Ca, Ce, Cl, Co, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sc, Sm, Th, and Zn. In addition, estimated values were also assigned for Hf, N, P, Sb, Sr and V determined by the Kjeldahl method and INAA

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Kawamoto, Mayumi Silva. "Produção de Materiais de Referência Para Nutrientes e Contaminantes Inorgânicos em Amostras de Ração e Tecido de Peixe." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-14032019-102135/.

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Para que o crescimento da produção pesqueira no Brasil aconteça de maneira sustentável é necessário o desenvolvimento de bases científicas e tecnológicas sólidas, que solucionem as demandas existentes nos diversos elos da cadeia produtiva. Uma das principais evidências da qualidade dos produtos é fornecida pelos resultados analíticos, cuja confiabilidade e exatidão podem ser asseguradas pelo emprego de materiais de referência (RM). Neste contexto, foi desenvolvido material de referência de ração para peixe para macro e micronutrientes e parâmetros bromatológicos e está em fase final de desenvolvimento um RM de tecido de peixe para nutrientes e contaminantes inorgânicos. A produção dos materiais seguiu as diretrizes das ISO Guias 30-35, considerando a preparação, envase, irradiação, massa mínima, homogeneidade, estabilidade a curto e a longo prazo e caracterização do material. Para produzir os RMs de ração e tecido de peixe, as amostras foram obtidas a partir de fornecedores comerciais. Os materiais foram secos/liofilizados, moídos, homogeneizados e envasados em frascos de vidro âmbar que, posteriormente, foram submetidos à irradiação com raios gama, para esterilização do material, visando o aumento do seu tempo de prateleira. A caracterização química do RM de ração foi efetuada através de um ensaio colaborativo, com a participação de laboratórios de diferentes instituições, públicas e privadas. A avaliação da estimativa da massa mínima, da homogeneidade e da estabilidade do material foi realizada utilizando-se como técnicas de determinação a espectrometria de emissão óptica com plasma acoplado indutivamente (ICP OES) e a espectrometria de massa por plasma acoplado indutivamente (ICP-MS). Foi possível observar que o lote de ração para peixe pode ser considerado homogêneo para Ca, Cu, Fe, Mg, Mn, Na e S, uma vez que não foi verificada diferença significativa no intervalo de confiança de 95%. A avaliação da estabilidade a longo prazo do RM de ração foi feita pela análise de resíduos da regressão em conjunto com a ANOVA e a avaliação da estabilidade a curto prazo foi obtida por meio de regressão linear simples. O RM de ração foi considerado suficientemente estável para ser armazenado à temperatura ambiente. Os resultados obtidos durante a produção do RM de ração e através do ensaio colaborativo possibilitaram a caracterização química e o cálculo das componentes de incerteza, sendo elaborado o documento com os valores de referência RM e as incertezas expandidas para cada um dos analitos avaliados. O RM de tecido de peixe foi avaliado em sua homogeneidade e estabilidade a curto prazo, sendo considerado homogêneo e estável para transporte a temperaturas inferiores a 37ºC.
For the growth of fisheries production in a sustainable way is necessary the development of sound scientific and technological basis, addressing the existing demands in the various links in the production chain. One of the main evidences of the quality of the products is provided by the analytical results, whose reliability and accuracy can be assured by the use of reference materials (RM). In this context, it was produced a RM of fish feed for macro-and micronutrients and proximates and it is in its final stage of development a RM of fish tissue for nutrients and inorganic contaminants. The production of reference materials followed the ISO Guides 30-35 norms: preparation and packaging, irradiation, minimum sample, homogeneity, short- and long-term stability, and material characterization. In order to produce a RMs of fish feed and fish tissue, the matrices were obtained from commercial suppliers. The samples were dried/freeze-dried, pulverized, homogenized and aliquoted into amber glass bottles, which later were subjected to gamma Ray irradiation (5-10 KGy), in order to increase its shelf life. The chemical characterization of the candidate fish feed RM was made through a collaborative trial with the participation of various laboratories of different institutions. The study of minimum sample, homogeneity and stability of the material were performed using inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) as determination techniques. The fish feed batch can be considered homogeneous for Ca, Cu, Fe, Mg, Mn and Na, since there was no significant difference in significance level of 0.05. Long-term stability study of the RM of fish feed was performed by the residual analysis in regression and ANOVA and the short-term stability study was performed by simple linear regression. The RM was considered sufficiently stable to be stored at room temperature. The data obtained along the production and through the collaborative trial allowed the characterization of the fish feed RM and the determination of uncertainties components. It was prepared the analysis document with the reference values and expanded uncertainties. The RM of fish tissue was evaluated in its homogeneity and short-term stability and its considered homogeneous and stable to be transported under normal conditions.

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Doyle, Wendy. "Maternal nutrition and low birthweight." Thesis, Brunel University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267895.

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Kato, Lilian Seiko. "Caracterização química de feijão para produção de material de referência certificado." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-26012015-151312/.

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Alimento base da dieta dos brasileiros, o feijão é a leguminosa de maior importância para consumo direto no mundo. Inúmeras pesquisas em relação às propriedades nutricionais do feijão comum e também do feijão de corda têm sido realizadas, no intuito de avaliar sua composição centesimal, mineral e fatores antinutricionais. Em relação à qualidade das determinações analíticas, sabe-se que os materiais de referência certificados (CRMs) estão se tornando cada vez mais necessários em procedimentos de medição. Contudo, ainda há escassez de CRMs para atender às demandas em todos os setores produtivos, especialmente na agricultura. O domínio da tecnologia para sua produção representa, portanto, um avanço estratégico, por colocar o país em condições de fornecer materiais específicos às próprias necessidades. Dessa forma, este trabalho envolveu a primeira etapa para elaboração de um material de referência certificado de feijão, com a caracterização química e nutricional dos principais tipos comerciais disponíveis no mercado, das espécies Phaseolus vulgaris L. (feijão comum) e Vigna unguiculata (feijão caupi), buscando atender demandas metrológicas específicas da pesquisa e da indústria alimentícia. Foram coletadas 55 amostras de feijão de dez tipos comerciais diferentes no varejo da cidade de Piracicaba. Determinaram-se os elementos químicos Br, Ca, Co, Cs, Fe, K, Mo, Na, Rb, Sc e Zn utilizando análise por ativação neutrônica, a composição centesimal empregando metodologia preconizada pela AOAC e o fator antinutricional ácido fítico segundo o método descrito por Grynspan e Cheryan (1989). Os resultados mostraram diferença significativa entre os tipos comerciais de feijão (p<0,05) para Br, Cs, Co, K, Mo, Na e Zn, e também para os teores de proteínas, cinzas, umidade e ácido fítico. O feijão fradinho, da espécie Vigna unguiculata, apresentou diferenças consideráveis em relação ao feijão comum da espécie Phaseolus vulgaris L., tendo a maior concentração média de Na e as menores concentrações médias de Ca, Co, K e cinzas (p<0,05). O feijão preto apresentou as maiores concentrações médias de Ca, Co, Fe, proteínas e ácido fítico, enquanto o feijão cavalo as maiores concentrações médias de K, Mo e Zn (p<0,05). O feijão carioca apresentou valores médios próximos à média global para todos os parâmetros avaliados, exceto para ácido fítico. Alta variabilidade foi identificada para Br, Cs, Mo, Na, Rb e Sc dentro de um mesmo tipo comercial, enquanto baixa variabilidade foi observada para K, Zn, cinzas e proteínas. O conjunto de dados resultantes da caracterização química das 55 amostras de feijão mostra que os tipos comerciais carioca, preto e fradinho são os mais indicados para produção de material de referência certificado. Considerando o critério de comutatividade, o feijão carioca pode ser utilizado para produzir um material de referência que represente todos os tipos comerciais estudados
Basic food of the Brazilian diet, beans are the most important leguminous for direct consumption in the world. Numerous researches on the nutritional properties of common bean and string bean have been performed in order to assess their centesimal and mineral composition as well the antinutritional factors. Regarding the quality of the analytical determinations, it is known that the certified reference materials (CRMs) are becoming increasingly necessary in measurement procedures. However, there is still lack of CRMs to meet the demands from all productive sectors, especially agriculture. Mastering the technology for their production therefore represents a strategic step forward, to put the country in a position to provide specific materials to own needs. Thus, this work involved the first step in developing a bean certified reference material, with chemical and nutritional characterization of the main commercial types available in the market, from the species Phaseolus vulgaris L. (common bean) and Vigna unguiculata (cowpea), meeting the specific metrological demand of research and food industry. In the retail market of the city of Piracicaba, 55 bean samples from ten different commercial types were collected. The chemical elements Br, Ca, Co, Cs, Fe, K, Mo, Na, Rb, Sc and Zn were determined by nêutron activation analysis, the proximate composition using methodology recommended by the AOAC and the anti-nutritional factor phytic acid, according to the method described by Grynspan and Cheryan (1989). The results showed significant differences between commercial bean types (p<0.05) for Br, Cs, Co, K, Mo, Na and Zn, and also for protein, ash, moisture and phytic acid. The black-eyed pea from Vigna unguiculata species showed considerable differences from the common bean Phaseolus vulgaris L. species, having the highest average concentration of Na and the lowest average concentrations of Ca, Co, K and ash (p<0.05). The black bean had the highest average concentrations of Ca, Co, Fe, proteins and phytic acid, while horse bean the highest average concentrations of K, Mo and Zn (p<0.05). The common bean showed mean values close to the global average for all parameters, except for the phytic acid. High variability has been identified for Br, Cs, Mo, Na, Rb and Sc within a commercial type, while low variability was observed for K, Zn, ash, and proteins. The data set resulting from the chemical characterization of 55 samples indicates that the commercial types common bean, black bean and black-eyed pea are more indicated for the production of the certified reference material. Considering the commutability criteria, the common beans could be used to produce a reference material representative of all commercial types studied

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Rhodes, Phillip Steven. "The interaction between maternal nutrient restriction and postnatal nutrient excess in an ovine model." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/12092/.

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Evidence from human and animal studies has highlighted the sensitivity of the developing fetus to environmental insults, such as maternal undernutrition, during gestation. These nutritional perturbations to the intrauterine milieu may engender a legacy of deleterious health consequences in adulthood. This thesis presents a series of studies which test the `mis-match‘ fetal programming theory; that is, whether a nutritionally poor diet prenatally interacts with a nutritionally excessive diet postnatally to overtly increase risk factors for adult disease. The effect of a maternal global energy restriction is contrasted against a maternal specific protein restriction, each fed during either early or late gestation. Adult offspring were subsequently exposed to an obesogenic environment (elevated feed with increased lipid content whilst restricting physical activity). Offspring metabolic flexibility and competence were assessed through routine blood samples throughout postnatal life and at 7, 18 and 24 months of age by glucose (GTT) and insulin (ITT) tolerance tests and body composition by dual energy x-ray absorptiometry. In general males appeared more susceptible to developmental programming than females at a number of timepoints. Furthermore, an increased first-phase or incremental area-under-the-insulin-response curve was observed in 1) offspring following maternal protein restriction in early gestation at 7 and 24 months of age, despite maternal protein restriction in late gestation significantly reducing birthweight and 2) in offspring exposed to maternal energy restriction during late gestation at 24 months of age in response to a GTT. Since, in both groups, the response of all offspring to an ITT (from a euglycemic baseline) was similar, infers that developmental programming in sheep followed by nutritional excess is first revealed as affecting either the pancreas (~insulin hypersecretion) or the liver (hepatic insulin resistance, reduced first-pass insulin metabolism). The studies illustrate the importance of habitual consumption of an `optimal’ balanced diet through gestation on postnatal health, especially in light of the current obesity epidemic.

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Foster, Michelle Rebecca. "Placental nutrient transport in pregnancies complicated by maternal diabetes." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251305.

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Wei, Julia Jia. "Maternal mood during pregnancy, methyl nutrient metabolism, and serotonin transporter." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/35857.

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Depression occurs in 15% of pregnant women and 1/3 are taking selective serotonin reuptake inhibitors (SSRIs) as antidepressants. The neurotransmitter, serotonin, plays a critical role in modulating stress responses and early brain development. Serotonin transporter (SLC6A4) regulates extracellular serotonin levels, and an insertion/deletion variant in the promoter (5HTTLPR) is associated with depression. Maternal mood and SSRIs may program newborns’ behaviour later in life. The underlying molecular mechanism for developmental programming may involve DNA methylation, which requires methyl nutrients as enzymatic cofactors. While low methyl nutrient status (folate and vitamin B₁₂) and a genetic variant in methylenetetrahydrofolate reductase (MTHFR C677T) have been associated with depression in adults, the role of methyl nutrient metabolism in depression during pregnancy remains unclear. Furthermore, little is known about the combined roles of methyl nutrient status and depression in the epigenetic regulation of SLC6A4. The experiments in this thesis explored whether disturbances in methyl nutrient metabolism and depressed mood during the 3rd trimester of pregnancy affect SLC6A4 methylation and expression in mothers and their newborns. Maternal folate status was positively associated with maternal SLC6A4 methylation at CpGs 1, 4, and 8 (P<0.05). Maternal 3rd trimester mood was inversely associated with SLC6A4 CpG 10 methylation in both mothers and newborns (P<0.05). Methylation at SLC6A4 CpG 8 was lower in newborns with mothers with the MTHFR 677TT genotype, and methylation at CpGs 6 and 10 were lower in newborns with the MTHFR 677TT genotype (P<0.05). Maternal SLC6A4 mRNA level was positively associated with mean maternal methylation and methylation at CpGs 5, 7, 8, and 10 (P<0.05). Yet, newborn SLC6A4 mRNA level was negatively associated with newborn methylation at CpGs 4 and 7 (P<0.05). Homozygosity for the minor allele for MTHFR C677T and 5-HTTLPR insertion/deletion variants in mothers were not associated with maternal mood (P>0.05). These results provide evidence to suggest that maternal mood during pregnancy and methyl nutrient metabolism may program SLC6A4 gene expression through DNA methylation in both mothers and their newborns. Mood during pregnancy and disturbances in methyl nutrient metabolism could set up life-long health consequences in the development of the offspring.

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Gilbert, Jeffrey Stephen. "Cardiorenal adaptations of the ovine fetus and offspring to maternal nutrient restriction." Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=1044392391&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Asopa, Sanjay. "Fetal cardiac development and cardiovascular response to maternal nutrient restriction during pregnancy." Thesis, University of Southampton, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536311.

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Gopalakrishnan, Gosala. "Maternal nutrient restriction during pregnancy and programming of offspring blood pressure control." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423303.

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Brennan, Kathryn. "Maternal nutrient restriction alters renal development and blood pressure regulation of the offspring." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439999.

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Mordhorst, Bethany Rae. "Influence of Maternal Nutrient Intake on Placental Vascular Function in Pregnant Beef Cows." Thesis, North Dakota State University, 2014. https://hdl.handle.net/10365/27383.

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Two experiments investigating impacts of maternal nutrition in beef cows were conducted; 1) to test the impact of duration of global nutrient restriction and subsequent realimentation throughout gestation on placentome capillary development; and 2) to test the response of protein supplementation on blood flow to the uterus and mammary gland in late gestation. In experiment one, realimentation following varying periods of nutrient restriction had minor alterations in angiogenic factor mRNA expression of as well as vascularity in the placentome. In experiment two, mammary gland blood flow was not affected, while protein supplementation decreased uterine blood flow. Calf birth weights were not influenced by maternal dietary treatment. Results of these studies are important when considering nutritional management of cows during gestation. Further research is warranted to investigate capillary function to determine how compensation is occurring when vascularity is not being drastically compromised with global maternal dietary restriction. Additionally the mechanism of how DDGS supplementation is decreasing blood flow to the uterus is a question which requires more exploration.

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Reyaz, Arshi. "Influence of Maternal Nutrient Intake on Placental Vascular Function in Pregnant Beef Cows." Thesis, North Dakota State University, 2014. https://hdl.handle.net/10365/26993.

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We hypothesized that global maternal nutrient restriction during early and mid-gestation followed by realimentation in pregnant beef cows would alter placental arterial vascular function. We tested changes in placental caruncular (CAR) and cotyledonary (COT) arterial sensitivity to bradykinin (BK), a potent vasodilator. Cows were randomly assigned to be nutrient restricted for 55 or 110 during early to mid pregnancy. On d 85, 140, and 254 cows were euthanized and CAR and COT arteries were isolated. Maternal nutrient restriction during early and mid-gestation allowed for placental compensation to overcome the loss of nutrients while realimentation returned placental arterial vosoactivity similar to control cows in response to BK. Further, CAR and COT placental arteries may respond to BK induced vasodilation through different pathways which is important when considering possible therapeutics for compromised pregnancies.

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Esposito, Nicole C. "Soil Nutrient Availability Properties of Biochar." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1096.

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Biochar’s high porosity and negative surface charge allows for numerous soil and plant benefits such as increased water retention, high nutrient availability, and plant growth. By analysing biochar’s effect of all of these factors, a system can be put in place in which soils can be remediated with the proper soil amendments. This report discusses and tests the effects of varying rates of biochar on pH levels, cation exchange capacity, and nutrient exchangeability (of calcium, magnesium, sodium, and potassium) in soil. Corn plants were also grown in soils of varying amendment types and analysed for plant growth and germination to determine soil effects on the plant. Testing showed significant differences between treatment types in all areas tested except plant germination. A 2:1 ratio of biochar to compost produced the best overall results for the soil used in testing. This treatment maintained acceptable levels of exchangeable nutrients while raising pH and cation exchange capacity, and also raised the plant growth in the soil by 30%. However, for added soil health, gypsum or calcium fertilizer should be added to the soil to remediate low calcium exchangeability. This testing confirmed that biochar does have a strong positive influence on soil and plant health when used in combination with compost.

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Brett, Kendra Elizabeth. "Maternal Phenotype, Directly Measured Physical Activity and Associations with Placenta Nutrient Transport Related Gene Expression." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32514.

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The intrauterine environment plays an important role in fetal development and downstream health. Given the rise in maternal obesity and the incidence of babies being born large-for-gestational-age, research is needed exploring the mechanisms through which maternal obesity and health behaviours affect the delivery of nutrients to the fetus. This thesis includes three manuscripts in the pursuit of two objectives: 1) To determine whether there are changes in placenta nutrient transport-related gene expression in response to obesity, excess gestational weight gain, and variations physical activity and diet, and 2) To examine whether the Pregnancy Physical Activity Questionnaire is a reliable estimate of physical activity during the second trimester of pregnancy. In manuscript 1, we found that maternal obesity was not related to placenta nutrient transport-related gene expression, with the exception of lower placental mTOR expression in obese women who delivered male offspring, however, gestational weight gain was related to the gene expression of key proteins in the placenta. In manuscript 2, it was determined that the Pregnancy Physical Activity Questionnaire significantly overestimates physical activity and is not correlated with direct measures of activity and thus should not be used in future research. In manuscript 3, we found that physical activity and diet modify the expression of the genes involved in placenta nutrient transport. Meeting physical activity guidelines was associated with lower expression of a fatty acid transporter and higher expression of an amino acid transporter, while sugar intake was related to the expression of a glucose transporter. Together, the studies that make up this thesis suggest that there are numerous factors that may be contributing to placenta nutrient transport-related gene expression in humans and that future research on the placenta ought to include direct measures of physical activity and maternal diet, as well as account for gestational weight gain with respect to the guidelines and fetal sex.

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Cowley, Michael Anthony. "Investigating the role of the imprinted Grb10 gene in the regulation of maternal nutrient transfer." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518301.

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Imprinted genes are a subset of loci, positioned on autosomes and the X-chromosome, which are expressed monoallelically in a parent-of-origin specific manner. The influence of such genes on the regulation of embryonic growth and postnatal energy homeostasis is well established. The parental conflict hypothesis predicts that, in utero, paternally-expressed genes will promote maternal resource acquisition and thus growth, whereas maternally-expressed genes will oppose this action, restricting resource investment in a single brood in the interests of the lifetime reproductive success of the mother. Grb10 is an imprinted gene which encodes the cytoplasmic adaptor protein Growth factor receptor bound protein 10. In the majority of tissues, Grb10 is expressed from the maternally-derived chromosome. Consistent with conflict theory, transgenic mice inheriting a disrupted Grb10 allele through the maternal line (Grb10Δ2-4m/+) exhibit embryonic overgrowth, although the mechanisms and signalling pathways responsible for this effect are unclear. Grb10Δ2-4m/+ mice also demonstrate enhanced insulin signalling and improved whole body glucose clearance, consistent with the established role of imprinted genes in the regulation of postnatal metabolism. An integrated LacZ gene-trap in the Grb10Δ2-4 allele failed to fully recapitulate endogenous Grb10 expression, notably within the central nervous system. To address this issue, a second transgenic mouse line, Grb10KO, was created. This allele produced strong LacZ reporter expression in the central nervous system, but only when transmitted through the paternal line (Grb10KO+/p), establishing Grb10 as the only known imprinted gene with a reciprocal imprinting profile between the central nervous system and peripheral tissues. Grb10KO+/p mice exhibit a social dominance phenotype, suggesting distinct roles for maternally- and paternally-expressed Grb10, consistent with their respective sites of expression. The current study characterised the Grb10KO allele at the genetic level, and in doing so, revealed a phenotypic difference between Grb10KOm/p and Grb10Δ2-4m/p mice for which a possible explanation was provided. Importantly, with this knowledge, the current study elucidated the genetic and molecular basis for inconsistencies in reporter expression between the two transgenic lines, identifying a novel tissue-specific enhancer element at the locus. In addition to the central nervous system, this enhancer appeared to be active in the mammary epithelium, identifying a novel site of Grb10 expression, which was pregnancy-dependent and specifically from the maternally-inherited chromosome. Characterisation of the functional significance of expression in this tissue revealed that maternally-expressed Grb10 mediates a supply/demand system between lactating mother and suckling pup, acting as a supply promoter and demand suppressor. This role is inconsistent with conflict theory, but suggests the maintenance of the Grb10 imprint in the mammary epithelium might be associated with improved coadaptiveness between mother and offspring. Intriguingly, in utero, Grb10 is both a demand and supply suppressor. When considered together, these findings suggest a wider role for maternally-expressed Grb10 in the homeostatic control of growth and achievement of optimal fitness.

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Bossu, Carla Maíra. "Produção e caracterização de material de referência de forrageira para nutrientes e contaminantes inorgânicos." Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/6280.

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Universidade Federal de Minas Gerais
The main aim of this work was to produce a candidate material for national reference material, the forage Brachiaria brizantha Stapf. cv. Marandu, containing known levels of contaminants (Cr, Pb, Cd, and As) and macro and micronutrients (Ca, P, Mg, K, Cu, Fe, Mn, Zn and Na). Brachiaria brizantha Stapf cv. Marandu was shown in 400 pots containing 25 kg of soil. The pots were kept in a greenhouse at Embrapa Southeast Livestock located in Sao Carlos, SP. A previous study was conducted in order to establish an appropriate concentration of contaminants that would not harm the dry matter production critically. In order to produce a reference material containing inorganic contaminants in its structure, the dose of 25 mmol/pots was chosen and added into 375 pots. The first harvest occurred after approximately 60 days of plant growth, and the second one after 120 days. Then, the samples were oven-dried at 45°C for 72 hours and grounded first in a cutting mill and then in an ultra-centrifugal mill to reduce particle size. It was produced 20 kg of dried and grounded material. After this, the homogenization and other processes were carried out, including packaging and gamma irradiation dosage in the range of 5-10 kGy to increase the shelf life. Other relevant studies were also undertaken, such as: particle size distribution, betweenbottles and within-bottle homogeneity evaluation, short and long term stability tests using ICP-MS techniques for As, Cd, Cr and Pb, and ICP OES for Ca, P, Mg, K, Cu, Fe, Mn , Zn and Na. Relative humidity and homogeneity between-bottles were also carried out using INAA. All tests presented results within the range of 95%, assuring homogeneity and stability of the candidate material for forage reference material. The consensus values for the 13 elements were determined by collaborative program. All these experiments were performed in accordance with the ISO Guides 30 to 35.
O objetivo do trabalho foi produzir material candidato a material de referencia nacional de forrageira Brachiaria brizantha Stapf. cv. Marandu, contendo teores conhecidos de contaminantes (Cr, Pb, Cd e As) e de macro e micronutrientes (Ca, P, Mg, K, Cu, Fe, Mn, Zn e Na). Foram montados 400 vasos com solo coletado da fracao 0-20 cm, o qual foi corrigido com calcario e N, P e K antes do plantio. Foi feito um estudo previo em 16 vasos, para a definicao de doses de contaminantes que nao prejudicasse de forma critica a producao de materia seca, sendo definida a dose de 25 mmol/vaso de Cr, Pb, Cd e As, adicionados na forma de sais, a cada um dos 375 vasos restantes. Apos aproximadamente 60 dias foi feito o primeiro corte da planta forrageira, sendo o segundo corte realizado apos 120 dias. Apos secagem em estufa a 45 oC e moagem em moinho de facas seguido de segunda moagem em moinho ultra-centrifugo, obteve-se aproximadamente 20 kg de material seco e moido. Apos essa etapa foi realizada a homogeneizacao em homogeneizador tipo Y, envase, irradiacao com raios gama na faixa de dosagem entre 5 e 10 kGy, visando ao aumento do tempo de prateleira e ao mesmo tempo a preservacao das caracteristicas originais da amostra. Em seguida realizou-se os estudos pertinentes, tais como: distribuicao de tamanho de particula, estudos de homogeneidade intra e inter-amostral e estudos de estabilidade a curto e longo prazo utilizando tecnicas de espectrometria de massa com plasma indutivamente acoplado (ICP-MS) para As, Cd, Cr e Pb e espectrometria de emissao optica com plasma indutivamente acoplado (ICP OES) para Ca, P, Mg, K, Cu, Fe, Mn, Zn e Na. Foi feito tambem estudo de umidade relativa e realizado estudo da homogeneidade inter-amostral utilizando analise por ativacao neutronica instrumental (INAA). Os resultados apresentaram medias dentro do intervalo de confianca de 95%, assegurando homogeneidade e estabilidade do material candidato a material de referencia de forrageira. Os valores de consenso para os 13 elementos foram determinados por meio de ensaio colaborativo. Todos estes experimentos foram realizados em conformidade com as ISO Guias 30 a 35.

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Verhalen, Tatiane Rosane. "Preparo e caracterização de material de referência de solo para nutrientes e contaminantes inorgânicos." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/6600.

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Financiadora de Estudos e Projetos
The certified reference materials make an important role in the establishment of traceability in analytical chemistry, ensuring reliability and accuracy to the measurements and are fundamental for the validation of analytical methods. The demand for new certified reference materials increases in all areas of knowledge, with emphases to the agriculture. Basis for the production of farming products, the demand for soil analysis is great and the existence of a reference material of a typical Brazilian soil is important to ensure the quality of results. In this context, the present work describe the preparate and the characterization of a national reference material for Cr, Pb, Cd, and As soil contaminants and Ca, P, Mg, K, Cu, Fe, Mn, Zn, and Na macro and micronutrients. The material was produced following the internationally accepted ISO Guides 30-35 norms considering the preparation and packaging, homogeneity, short and long term stability, and material characterization and certification. A Typic Paleudult soil was artificially contaminated with As, Cd, Cr, and Pb, added as salt solutions from Pb(NO3)2; Cd(NO3)2.4H2O; Na2HAsO4.7H2O, and Cr(NO3)3.9H2O salts. After 12 month of contamination, 65 kg of soil was dried at room temperature, ground (particles size < 390μm), homogenized, packaged and irradiated with gamma ray (20 - 25 kGy) aiming to increase the shelf-life. The analyte soil extractions were based on methodology recommended by Brazilian legislation (CONAMA N° 420), with in turn follows the protocol established by American environmental agency (USEPA 3051). It was performed by assisted microwave oven with the use of 14 mol L-1 HNO3. The evaluation of the estimate minimum amount, homogeneity and stability of the material were carried out, using inductively coupled plasma optical emission spectroscopy (ICP OES) determination technique. The results were submitted to analysis of variance of single factor (ANOVA). The homogeneity and stability of the material presented means within a confidence interval of 95% for As, Cd, Pb, Cr, Ca, Cu, Fe, Na, K, Mg, Mn, and P. The chemical characterization of the material was performed through a collaborative test and the uncertainties related to each step of the material prepare were calculated to obtain the expanded uncertainty for each one of the analytes and to the final drafting of the control chart with the results of the reference material.
Os materiais de referência certificados desempenham papel fundamental no estabelecimento da rastreabilidade em química analítica, assegurando confiabilidade e exatidão dos resultados de medição e são fundamentais para a validação dos métodos analíticos. A demanda por novos materiais de referência cresce a cada dia, em todas as áreas do conhecimento, entre as quais destaca-se a agricultura. Base para a produção dos produtos agrícolas, a demanda por análises de solo é grande e a existência de um material de referência de solo tipicamente brasileiro é importante para garantir a qualidade dos resultados. Nesse contexto, o presente trabalho descreve o preparo e a caracterização de um material de referência nacional de solo para os contaminantes Cr, Pb, Cd e As e os macro e micronutrientes Ca, P, Mg, K, Cu, Fe, Mn, Zn e Na. O material foi produzido seguindo as etapas, estabelecidas pelas normas ISO GUIAS 30 a 35, internacionalmente aceitas no preparo e envase do material, na avaliação da homogeneidade, no teste de estabilidade a curto e a longo períodos e na certificação do material. O solo utilizado, latossolo vermelho amarelo foi artificialmente contaminado com Cr, Pb, Cd e As, adicionados na forma de soluções preparadas a partir dos seguintes sais: Pb(NO3)2; Cd(NO3)2.4H2O; Na2HAsO4.7H2O e Cr(NO3)3.9H2O. Após 12 meses da adição dos contaminantes, 65 kg de solo foi seco a temperatura ambiente, moído (granulometria < 390 μm), homogeneizado, envasado e irradiado com radiação gama (20 - 25 kGy), visando o aumento do tempo de prateleira. O preparo da amostra visando obtenção dos teores extraíveis dos analitos empregou ácido nítrico 14 mol L-1 com aquecimento assistido por radiação micro-ondas e foi baseada em metodologia recomendada pela legislação brasileira (CONAMA N° 420), que por sua vez segue protocolo estabelecido pelo órgão ambiental americano (USEPA 3051). A avaliação da estimativa da massa mínima, da homogeneidade e da estabilidade do material foi realizada utilizando-se como técnica de determinação a espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Os resultados foram submetidos à análise de variância de fator único (ANOVA). A homogeneidade e a estabilidade do material apresentaram médias dentro do intervalo de confiança de 95% para As, Cd, Pb, Cr, Ca, Cu, Fe, Na, K, Mg, Mn e P do material candidato a material de referência de solo. A caracterização química do material foi realizada por meio do ensaio colaborativo, com a participação de laboratórios nacionais e as incertezas associadas a cada passo da preparação do material foram calculadas para se obter a incerteza expandida para cada analito em estudo e a elaboração final da carta de controle com os resultados do material de referência.

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Gedi, Mohamed Abdulkadir. "Nutrient composition and digestibility of chloroplast rich fractions from green leaf materials." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/43285/.

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Green leaf material is recognized as a good source of many valuable nutrients including vitamins, fatty acids and minerals. Chloroplast-rich-fractions (CRFs) were prepared from green plant species and their nutrient composition compared with the whole leaf materials (WLMs). Digestibility of CRFs from spinach was also compared with the WLM using simulated in vitro oral, stomach and small intestinal conditions. The impact of pancreatic lipase-related protein 2 from guinea pig (gPLRP2) on the hydrolysis of galactolipids compared to neutral lipid, Tributyrin was subsequently determined in vitro. Porcine pancreatic lipase was also used against the same substrates compared to gPLRP2. Furthermore, spinach CRFs and WLMs were fed to zebrafish and the impact of CRFs and WLMs on growth performance and transition of certain compounds into zebrafish body was evaluated. Results indicated that compared with the WLM, the CRFs were enriched in more lipids and fatty acids, and more proteins and amino acids. Spinach CRFs possessed the highest α-tocopherol (62 mg 100 g-1 , dry weight (DW)), β-carotene (336 mg 100 g-1 DW) and lutein (341 mg 100 g-1 DW) contents, whilst grass CRFs had the highest alpha-linolenic acid (ALA) concentration (69.5 mg g-1). Of the minerals, iron was most notably concentrated in CRF. The digestive conditions caused changes in the structure and composition of the material providing some indication of its digestibility and bioaccessibility. Whilst PLRP2 was more active on galactolipids, with moderate reaction against the neutral lipid, pancreatin indicated higher activity on Tributyrin with almost no activity against MGDG. Diets with 10% zebrafish meal reduction improved growth rate with significant reduction in feed conversion ratio (FCR) compared to the control. CRFs diets showed greater ALA content and distinct pigmentation of zebrafish egg and flesh due to the CRF carotenoids. Overall, the results indicated that CRF is a potential digestible source of vital nutrients.

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Jakrawatana, Napat Civil &amp Environmental Engineering Faculty of Engineering UNSW. "An integrated decision support tool for more sustainable management of biomass resources in agricultural regions." Awarded By:University of New South Wales. Civil & Environmental Engineering, 2009. http://handle.unsw.edu.au/1959.4/44547.

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Agriculture currently faces a number of environmental sustainability issues. Three key issues that are the focus of this study are greenhouse gas emissions, depletion of mineral phosphorus resources and cadmium contamination in agricultural soil. Biomass can potentially be used as a renewable energy source and can also be returned to improve the nutrient and drainage structure of agricultural soils. Sustainable management of biomass and agriculture can have significant impacts on reducing greenhouse gas emissions from a region. Moreover, it reduces the demand for external energy supply, phosphorous (P) based fertilizer, and it??s associated Cadmium (Cd) impurity which can contaminate the soil, plant and food chains. These three issues have typically been considered separately, and managed by different agencies or organisations. The aim of this thesis is to develop an integrated decision support tool that can be used for evaluating alternative options for management and resource recovery from biomass for enhancing recovery of energy, returning carbon (C) and phosphorus (P) from biomass back to soil, reducing greenhouse gas emissions and also cadmium (Cd) contamination in an agricultural region. This research employed a combination of the tools of Material Flow Analysis (MFA), Geographic Information System (GIS) and Cost-Benefit Analysis (CBA). MFA is used as the primary tool for this research. GIS and CBA are combined with MFA in later stages of the overall procedure to develop an integrated decision support tool. This integrated tool has been applied to the Murrumbidgee Irrigation Area (MIA) in Australia. Tracking the flow of essential substances using MFA has identified current resource management efficiency and substances accumulation across the region. Integrating a spatial analysis tool (GIS) with MFA has provided a feedback driven monitoring tool for evaluating trends of spatial accumulation of substances on agricultural land. This enables the time remaining before acceptable limits are exceeded to be estimated on a spatial basis. Integrated MFA and CBA has been applied to evaluate the tradeoffs and potential synergies of alternative biomass management options. Overall the tool can assist in evaluating the effectiveness of alternative scenarios and visualise the results to stakeholders in a systematic way.

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Adams, Zachry Clay Adams James F. "Comparison of broiler litter, broiler litter ash with reagent grade materials as sources of plant nutrients." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Thesis/ADAMS_ZACHRY_50.pdf.

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Rosa, Rodrigo Amighini 1985. "Fluxos de nutrientes e material particulado na bacia de drenagem do complexo estuarino de Paranaguá - PR." reponame:Repositório Institucional da UFPR, 2011. http://hdl.handle.net/1884/25107.

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Resumo: As fontes alóctones de materiais para os ecossistemas costeiros têm as bacias fluviais como principais vias de acesso. A bacia hidrográfica litorânea do Paraná apresenta um elevado potencial erosivo, decorrente da alta instabilidade natural e pela ação antrópica em algumas regiões. O Complexo Estuarino de Paranaguá (CEP) apresenta dois eixos principais: L–O, que corresponde à Baía de Paranaguá e N–S, que contempla a Baía das Laranjeiras. Na primeira, foram investigados os rios Cachoeira, Cacatú, Faisqueira, Nhundiaquara, Guaraguaçú e Sagrado, e na segunda, os rios Guaraqueçaba, Serra Negra e Tagaçaba. As concentrações e os fluxos de nutrientes e material particulado foram quantificados ao longo de um ciclo anual nas bacias fluviais do CEP. A aplicação do índice de potencial de eutrofização costeira (IPEC) permitiu estimar os potenciais das bacias fluviais em eutrofizar o sistema estuarino e áreas costeiras adjacentes. O rio que apresentou maior vazão no CEP foi o Cachoeira, responsável também pelas maiores descargas de MPS (23 Ton/Dia no período chuvoso), nitrato (692 Kg/Dia no período seco), nitrogênio inorgânico dissolvido (NID) (759 Kg/Dia no período seco), fósforo inorgânico dissolvido (PID) (49,45 Kg/Dia no período chuvoso) e silicato (12217 Kg/Dia no período seco) para o sistema. Variações sazonais significativas foram observadas na maioria dos rios para os diferentes aportes. As diferenças espaciais entre a Baía de Paranaguá e a Baía das Laranjeiras foram significativas somente para a concentração e aporte de nitrito. O IPEC exibiu, na maior parte dos rios, valores negativos, indicando ausência de potencialidade de eutrofização costeira pelo aporte fluvial. Apenas o rio Guaraguaçú apresentou valor positivo de IPEC, demonstrando o pequeno potencial de eutrofização costeira causado pelo excesso de N total em relação à sílica dissolvida. As razões N/P obtidas a partir das concentrações molares observadas nos rios que compõem o CEP indicam, em sua maior parte, limitação potencial pela disponibilidade de P em relação ao N. Os rios Guaraguaçú e Tagaçaba apresentaram, no entanto, razões N/P abaixo de 16, configurando assim ambientes que podem sofrer limitação por N. As razões calculadas a partir dos valores molares de N e P, em relação a Si foram baixas, demonstrando elevada disponibilidade de Si, o que permite inferir que os rios investigados no CEP não apresentam concentrações elevadas de nutrientes (N e P) provenientes de fontes antrópicas. Com base nos resultados deste estudo, os principais fatores que controlam os fluxos e concentrações nas bacias de drenagem do CEP são: a geomorfologia, os regimes pluviométricos, e as atividades antrópicas. De acordo com a resolução CONAMA 357/05, os rios investigados apresentaram concentrações de nutrientes e clorofila-a abaixo dos limites críticos preconizados, e podem ser inseridos nos padrões de águas doces da classe 1, se levado em conta apenas os parâmetros investigados. Este trabalho forneceu as informações necessárias para a elaboração e do balanço de materiais no CEP, demandando, portanto, estudos adicionais que contribuam para uma melhor compreensão dos processos biogeoquímicos que atuam neste sistema.

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De, La Torre Mary McCarter. "Maternal anthropometric measures and nutrient intake during the second trimester of pregnancy of normal weight and overweight gravidas." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45644.

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Height, skinfold, and circumference measurements were obtained from 29 normal weight and 17 overweight (>110% of desirable weight for height) healthy pregnant women every four weeks during their second trimester of pregnancy. The mean weight gain and food intake values were not significantly different for both groups. Measurements increased at a greater rate for the normal weight gravidas than for the overweight gravidas in almost every case. For both groups, increases in fat stores were greater in the central sites than in the peripheral sites. No clear relationship between age, prepregnant weight, and weight gain during the second trimester with the birthweight of the baby was found. The infant birthweights of both groups were at an optimal level ( >2500 grams) except for one (born to the mother 151% of her desirable weight for height). The similarity in results for the two groups is greatly due to there not being a large enough difference in prepregnant weights between the two groups. Nevertheless, the results do lend support to a 20 to 30 pound weight gain for an optimal outcome of pregnancy for healthy pregnant women with a wide range of prepregnancy weights. Those women 150% or more of their desirable weight for height may need to gain on the lower end of the spectrum due to their excess endogenous reserves and to possible harm to the fetus with large gains.
Master of Science

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Khosa, Mbokota Candy. "An investigation into the potential of crude and partially separated material of selected non-crop plant species as control agents of root-knot nematodes (Meloidogyne incognita) in tomato / Mbokota Candy Khosa." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8705.

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Plant-parasitic nematodes (PPN) are a serious problem in vegetable production and can cause severe damage to several crops. In rural, low-input farming nematode damage is much higher and yields can be completely destroyed. Some Commercial nematicides have been withdrawn from the market due to health and environment concerns. These need to be replaced by alternative nematode control strategies of which soil amendments is one alternative. Nine non-crop plant species used in various forms in traditional healing, viz. Cassia abbreviata, Cissus cactiformis, Euphorbia ingens, Ipomoea kituiensis, Maerua angolensis, Senna petersiana, Synadenium cupulare, Tabernaemontana elegans and Urginea sanguinea were screened under glasshouse conditions for their effect on the plant-parasitic nematode (PPN) (Meloidogyne incognita) on tomato. Subsequent assessments in microplots and in the field supported the glasshouse results in terms of suppression of root-knot nematode numbers with crudely milled soil amendments of C. cactiformis, M. angolensis and T. elegans. Tomato growth responses in these trials showed a tendency of phytotoxic effects after treatment of soil with crude leaf meal of E. ingens and S. cupulare. In the microplot study, the overall soil-amendment treatment effect was greater than that of three soil types on the performance of the tomato, although soil type might have had an effect on nematode suppression. Due to lack of correspondence between tomato leaf nutrient contents and the nutrient contents of the soil amendments it is suggested that these noncrop materials had negligible soil fertilization effects. In vitro bioassay studies confirmed that extracts of varying polarity of both plant products M. angolensis and T. elegans might be toxic to J2 stages of the root-knot nematode M. incognita. All extracts tested of M. angolensis caused immobility of J2, whereas only three extracts of T. elegans affected mobility of J2 adversely. Duration to 50 % effect, as well as extract concentration to cause immobility of the J2 varied but where movement ceased the J2 did not recover for up to 98 hours. This study has demonstrated the potential of locally available botanical materials for use as amendments in plant-parasitic nematode management and tomato growth and productivity improvement. This would particularly be true for small-scale application in subsistence agriculture. It is believed that these amendments could be used as control measures in integrated nematode control strategies. Their potential use could be adopted by small-scale farming communities, domestic gardeners and commercial farmers in the Mpumalanga, Limpopo and Kwazulu/Natal Provinces of South Africa where the relevant materials are available in useful quantities. Over-exploitation of natural resources should be avoided at all cost, however.
Thesis (PhD (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

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Oliveira, Marielle Ferreira de. "Tratamento de esgotos sanitários em sistema combinado anaeróbio/aeróbio utilizando lodo como fonte endógena de carbono." Universidade Estadual da Paraíba, 2012. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/1720.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The research aimed to treat sewage through combined anaerobic/aerobic system, using primary sludge and lysed excess sludge as an endogenous carbon source for removal of nutrients, aiming to produce effluent with low concentrations of organic material and nutrients and lower production excess sludge. The experiment was conducted in three phases. In the first, were performed respirometric tests as tool to assess the biodegradability of lysed biological sludge, through by techniques of cellular lysis induced: mechanical action, thermal and acid-base reaction. In the second phase, was monitored a Sequential Batch Reactor (SBR) together with Fermentation and Hydrolysis Reactor (FHR), which received excess sludge of SBR, tritured by mechanical action and primary sludge. SBR and FHR were operated with TRC of 3.36 and 10 days respectively. The third phase consisted of an anaerobic reactor followed by Immobilized Submerged with support Medium (polyurethane synthetic sponge) Aerated Reactor (ISMAR) operated in recirculation batch system. The results obtained from the respirometric tests found that the thermal sludge showed concentration biodegradable readily material greater than the tritured sludge and treated sludge by acid-base reaction. Values of the percentages of COD solubilized varied from 1.6% to 4.2%, with an average of 2.6%. The system presented promising results for the removal of nutrients, with removal efficiency of 85%, 93% and 98% for phosphorus soluble, nitrate and nitrite, respectively. However, the final effluent was maintained with concentration average of ammonia of 27 mgN-NH , considered out of the discharge standards. The combined system, anaerobic reactor and Immobilized Submerged with support Medium Aerobic Reactor (ISMAR), removed efficiently carbonaceous material (88%), TSS (86%), SSV (90%), TKN (94%) and N-NH4 - (96%). Producing effluent with average concentrations of nitrite and nitrate, respectively of 0.19 mgN-NO2-.L-1 and 2.52 mgN-NO3-.L. After addition of primary sludge the system, this presented a better performance with efficiency of COD removal gross and filtered 95%. However, the process of phosphorus removal was considered unsatisfactory since there was sludge disposal in the ISMAR reactor. Introducing an efficiency of removing just 20% for total phosphorus and 22% for the orthophosphate.
A pesquisa teve como objetivo principal tratar esgotos sanitários através de sistema combinado anaeróbio/aeróbio, utilizando lodo primário e lodo de excesso lisado como fonte endógena de carbono para remoção de nutrientes, buscando produzir efluente com baixas concentrações de material carbonáceo e de nutrientes e menor produção de lodo de excesso. O experimento foi realizado em três fases. Na primeira, foram realizados testes respirométricos como ferramenta para avaliar a biodegradabilidade de lodo biológico lisado, por meio de técnicas de lise celular induzida: ação mecânica, térmica e reação ácido-base. Na segunda fase, foi monitorado um Reator em Batelada Seqüencial (RBS) conjuntamente com Reator de Hidrólise e Fermentação (RHF), o qual recebia lodo de excesso do RBS, triturado por ação mecânica e lodo primário. O RBS e o RHF foram operados com TRC de 3,36 e 10 dias, respectivamente. A terceira fase foi constituída de reator anaeróbio seguido de reator aerado com meio suporte (esponja sintética de poliuretano) submerso imobilizado (RAMSI) operado em regime de bateladas com recirculação. Os resultados obtidos através dos testes respirométricos constataram que o lodo térmico apresentou concentração de material rapidamente biodegradável superior ao lodo triturado e ao lodo lisado por reação ácido-base. Os valores dos percentuais da DQO solubilizada variaram de 1,6% a 4,2%, com uma média de 2,6%. O sistema apresentou resultados promissores para a remoção de nutrientes, com eficiência de remoção de 85%, 93% e 98% para fósforo solúvel, nitrato e nitrito, respectivamente. Entretanto, o efluente final manteve-se com concentração média de nitrogênio amoniacal de 27 mgN-NH4.L-1, considerada fora dos padrões de lançamento. O sistema combinado, reator anaeróbio e reator aeróbio com meio suporte submerso imobilizado (RAMSI), removeram de forma eficiente material carbonáceo (88%), SST (86%), SSV (90%), NTK (94%) e N-NH4 -(96%). Produzindo efluente com concentrações médias de nitrito e nitrato, respectivamente de 0,19 mgN-NO e 2,52 mgN-NO3 -.L-1. Após a adição do lodo primário no sistema, este apresentou um melhor desempenho, com eficiência de remoção de DQO bruta e filtrada de 95%. No entanto, o processo de remoção de fósforo foi considerado insatisfatório, visto que não havia descarte de lodo no reator RAMSI. Apresentando uma eficiência de remoção de apenas 20% para o fósforo total e 22% para o ortofosfato.

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Nikiema, Sompassaté Josiane. "Attenuation of greenhouse gas emissions by means of methane biofiltration optimization of the operating parameters." Thèse, Université de Sherbrooke, 2008. http://savoirs.usherbrooke.ca/handle/11143/1911.

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The main goal of this work has been that of optimizing the operating conditions of a biofilter, intended for the control of methane, an important greenhouse gas widely emitted by older or smaller landfill installations.The specific objectives were: (1) to select a suitable packing material (of organic or inorganic type); (2) to optimize the concentrations of input nutrients, mainly consisting of nitrogen, phosphorus, potassium and copper, which are intended to be introduced via the nutrient solution; (3) to determine the optimized values of the most important design parameters, such as the methane inlet load (which depends on the air flow rate and the inlet methane concentration); and (4) to model the biofilter performance. Firstly, the comparison of the two packing materials, one of organic type, and the other of inorganic type, has revealed that the latter was the more appropriate material for the methane biofiltration. Then, through the use of the selected packing material, the influence of each individual nutrient on the efficiency of the process has been investigated.The results obtained have shown that both nitrogen and phosphorus concentrations have to be controlled, while potassium and copper were revealed as being nutrients of only minor importance. Secondly, the optimization of the inlet gas flow rate and of the inlet methane concentration (and consequently, of the methane inlet load also), has been performed. According to the results of the studies, these parameters require good control during methane biofiltration because a limitation in biofilter performance could otherwise be induced. In addition, it was noted that the increase in the inlet gas flow rate led generally to a greater decrease of the methane conversion than the one induced by the inlet methane concentration. Finally, a new method, based on the use of solid extracts sampled from the methane biofilter, has been applied to the determination of methane biofilter kinetic parameters. Following this study, a steady state model of the methane biofiltration, taking into consideration the important operational parameters, as identified previously, has been developed. One particular feature of this model is that it takes into consideration the influence of the biofilter average temperature.The prediction results, obtained with the use of the model, have been successfully compared with the experimental results.

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31

Deenik, Jonathan Leonard. "Correcting soil nutrient deficiencies with organic materials in the atoll soils of the Marshall Islands." Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/597.

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The coralline soils of atolls suffer from multiple nutrient deficiencies that severely limit crop growth. This study was conducted to assess the nutrient status of the soils of the inhabited atolls within the Marshall Islands (MI), and to determine what local materials could be used to correct deficiencies limiting crop growth. Surface and subsoils from 25 atolls were collected and analyzed for their chemical properties, and soil test results were evaluated with a missing element pot study. Soil tests revealed that the MI soils were severely deficient in K (0.12 cmol c kg -1 ) and marginally deficient in Cu (0.13 ug g -1 ). The missing element study showed that the soil was deficient in K, S, N, P, and Cu. An incubation experiment and a series of greenhouse experiments were conducted to evaluate the ability of locally available organic materials to mineralize N and supply adequate nutrients to crops. Vigna marina and fish meal showed the highest N mineralization capacity, and the Gompertz equation provided the best fit. Chinese cabbage plants grew as well in soils amended with chicken manure, Vigna marina , and copra cake as they did in soil treated with chemical fertilizers. Plants grown in soil amended with fish meal did not grow as well due to inadequate K supply. Nitrogen recovery was highest in V. marina treatment at 92% followed by the chemical control (83%), chicken manure (34%), fish-meal (18%), and copra cake (9%). Added coconut leaves immobilized N and resulted in very poor cabbage growth. Comparisons between relative growth rate (RGR) and nutrient relative accumulation rate (RAR) showed that nutrients supplied from the V. marina amendment to the cabbage plant matched plant demand. In a rate experiment in the greenhouse, adding 10.1 g kg -1 of V. marina leaves (dry weight) supplied 350 mg N kg -1 to 5 week-old corn plants representing 38% of the total amount of N added in the amendment. Splitting the application quantity improved corn growth at the highest addition rate. Copra cake showed less promise as a suitable organic amendment. Supplementing copra with chemical N and P, and V. marina leaves with and without Cu and B did not improve crop growth compared with copra alone. The soil exhibited low P adsorption capacity, and corn and lettuce growth responded to high Olsen P soil levels. The results of the greenhouse experiments showed that V. marina is a potential organic fertilizer material to correct soil nutrient deficiencies for good crop growth in the Marshall Islands.

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32

Lingas, Rania I. "The impact of acute maternal nutrient restriction on the development and long-term function of the hypthalamo-pituitary-adrenal axis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0018/MQ54185.pdf.

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33

Downing, Diane Elaine. "Maternal anthropometric measures and nutrient intake during the second and third trimesters of pregnancy of normal weight and overweight gravidas." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/101271.

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Weight, height, skinfold thicknesses, circumference measurements, and 72-hour food records were collected from pregnant women (N=51) at four-week intervals between the 12th and 40th weeks of gestation. Subjects were divided Into two groups according to percent standard prepregnant weight for height: overweight > 110% (N=17) and normal weight < 110% (N=28). Changes In weight, skinfold thicknesses and circumference measurements were similar between the two groups during the third trimester (weeks 28 to 40 of gestation). Significant increases in weight (1.58 kg per four weeks) and waist circumference and significant decreases in calf and abdominal skinfold thicknesses are reported. When the second and third trimesters (weeks 12 to 40 of gestation) were considered mean weight gain was 1 .87 kg per four-week interval. Overweight gravidas demonstrated a significantly greater decrease in abdominal skinfold thickness than normal-weight gravidas. The patterns of change over the second and third trimesters were different between the two groups for abdominal, knee, and calf skinfold thickness, hips and thigh circumference, body fat, and percent body fat. Caloric and macronutrient consumption was similar between groups and did not change throughout the second the two and third trimesters. Maternal weight gain was significantly associated with infant birth weight in both groups.
M.S.

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Hijo, Carlos Alberto Grossi. "Quantificação do efeito do açude castanhão sobre o fluxo de material particulado em suspensão e nutrientes para o estuário do rio jaguaribe, Ceará - Brasil." reponame:Repositório Institucional da UFC, 2009. http://www.repositorio.ufc.br/handle/riufc/11428.

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HIJO, C. A. G. Quantificação do efeito do açude castanhão sobre o fluxo de material particulado em suspensão e nutrientes para o estuário do rio jaguaribe, Ceará - Brasil. 2009. 39 f. Dissertação (mestrado em Ciências Marinhas Tropicais) - Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, 2009.
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The coastal zone is composed by highly environmental relevance ecosystems therein biodiversity is based on transitional land and marine features. This area has large biological productivity which is sustained by intricate biogeochemistry cycle of chemical species influenced by both adjacent watershed and coastal processes. Another feature of this area is the highly anthropogenic pressures that drive significant modifications of riverine material fluxes. Among such modifications, we can exemplify the damming of rivers and reservoir flooding usually occurred on the State of Ceará. The semi-arid climate enforce a large scheme of water management based on reservoir flooding which might induce changes on riverine fluxes from watershed to the coast as well as the ecosystem feature modification. Considering the above-mentioned scenario, this work aim to quantify the fluxes and budgets of water, suspended matter, and nutrients for the Castanhão reservoir from which the reservoir retention or export capacity of the riverine fluxes of the Jaguaribe watershed to the coast were estimated. Across the Castanhão reservoir water sampled were collected at three areas to characterize the concentration, fluxes, and budgets of riverine materials. According to proposed budget, there were a reduction of suspended matter, phosphorous, and nitrogen concentration. Additionally, the strong reduction of water outflow compared to inflow into reservoir was measured and it is the main process inducing the modification of riverine material fluxes. The budgets showed that the Castanhão reservoir and the operational dam procedure invert the natural functioning of the portion of Jaguaribe drainage basin. According to these results the reservoir changes the land-sea water, suspended matter and nutrient fluxes reducing and trapping from 88% to 98% of inflow loads into reservoir over hydrological and chemical conditions measured.
A zona costeira abriga um mosaico de ecossistemas de alta relevância ambiental, cuja diversidade é marcada pela transição de ambientes terrestres e marinhos. Esta área representa uma elevada produção biológica sustentada por um intricado ciclo biogeoquímico de espécies químicas que acopla processos relacionados tanto à bacia de drenagem dos rios que deságuam nestas áreas quanto os que ocorrem na zona costeira. Outra característica destas áreas é a intensa ação antrópica que tem sido responsável por alterações significativas nos fluxos fluviais destes materiais. Dentre estas alterações podemos exemplificar o barramento dos rios através da formação de reservatórios, usualmente observadas no Estado do Ceará. Devido às condições climáticas imposta pelo clima semi-árido, o Estado do Ceará tem a necessidade de manter um esquema de manejo hídrico baseado na construção de açudes que podem modificar os fluxos fluviais para a zona costeira sugerindo a indução das características destas áreas. Diante do cenário descrito, o objetivo deste estudo é quantificar os fluxos de água, nutrientes e material particulado em suspensão (MPS) ao longo do açude Castanhão e formular balanços de massa com os quais podemos inferir sobre a capacidade e a intensidade do açude em reter ou exportar materiais fluviais da bacia de drenagem do rio Jaguaribe em direção à zona costeira. Ao longo do açude Castanhão foram escolhidos três pontos para a realização das amostragens e a caracterização das concentrações, fluxos e balanços dos materiais fluviais. Segundo o balanço proposto houve uma redução das concentrações de espécies de fósforo e nitrogênio e do MPS. Associado a esta redução pode observar uma intensa redução da vazão de água na entrada em relação à saída da barragem sendo o principal processo que induz a modificação do fluxo fluvial. Os balanços de massa mostram que o açude Castanhão e a rotina de operação da barragem invertem o funcionamento natural desta parte da bacia de drenagem. Segundo os dados apresentados, o açude Castanhão modifica o fluxo fluvial de água, MPS e nutrientes no rio Jaguaribe podendo reter até 98% da carga de entrada e conseqüentemente a transferência destes materiais para a zona costeira.

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Kassa, Meheret. "Phosphorous Desorbing Capacity of the Filter Materials Polonite® and Sorbulite®." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171844.

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Replacing the lost Phosphates from different ecosystems is not a question it’s an onus. This none replaceable and renewable resource is one of the vital nutrients where without it, cells, crops and human beings cannot function and live. Though available in environment, its natural cycle is disturbed as its need especially in agriculture sector increases significantly. Phosphorus recovery from waste water sorbents is one of the innovative and promising concepts. The core goal of this paper is to evaluate the phosphorus desorbing capacity of two reactive materials (waste water sorbents) using chemical extracts. The experimental work emphasized on investigation four extracts, HNO3, NaHCO3, P-AL and H2O on phosphate desorption capacity of two inorganic reactive materials namely Polonite® and Sorbulite® which are widely known for their high P-sorption capacity. The kinetics and desorption were examined in batch experiments and consequently the plant availability were investigated using Flow Injection Analyzing (FIA) spectroscopy (wet chemistry) method. The maximum average orthophosphate desorption at 100 rpp for 48 hrs was interpreted to be 33.12 mg g−1and 3.11 mg g−1 from Sorbulite® and Polonite® respectively using 4M HNO3 extract. The orthophosphate desorption characteristic using the above extracts tended to decrease in the following order HNO3 ≤ P-AL ≤ NaHCO3 ≤ H2O. Polonite® shows a higher recovery potential, where almost 6 times higher ammonium lactate (AL)-extractable P was observed when compared with Sorbulite®. Batch experiment was proved to be a tool for investigating and evaluating Phosphorus desorption capacity of mineral-based filter materials.

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36

Kremmyda, Lefkothea-Stella. "Salmon in Pregnancy Study (SIPS) : the effects of increased oily fish consumption on maternal nutrient intake, fatty acid status and immunity." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/196579/.

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The prevalence of childhood atopic diseases (eczema, asthma, allergies, hay-fever) has increased during the last 30 years. Epidemiological studies link higher fish intake during pregnancy with lower risk of atopy in the offspring. Oily fish provide the long chain (LC) n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as vitamin D and antioxidants (selenium). Fish oil provides EPA and DHA and fish oil supplementation during pregnancy alters offspring immunity in a way that would be consistent with lowered risk of atopy. There are no studies of oily fish intervention in pregnancy. The Salmon in Pregnancy Study (SIPS) is the first randomised controlled trial of oily fish intervention during pregnancy. The main outcome measures of SIPS were the clinical signs of atopy in the offspring (not reported here). The current thesis presents and discusses results of SIPS mainly relating to the mother. The hypotheses examined here are that increased oily fish consumption during pregnancy will: a) increase maternal LC n-3 PUFA intake b) increase maternal LC n-3 PUFA status, c) alter maternal immunity, which may influence the developing foetal immune system in a way that would decrease atopy risk for the offspring. Pregnant women (n = 123) with high risk of having atopic offspring and with low habitual intake of oily fish (≤ 2/month) were randomised at 20 weeks of pregnancy to either consuming 2 portions/week of farmed salmon (n = 62) or continuing their habitual diet (n = 61) until the end of pregnancy. The women attended a clinic at weeks 20 (n = 123), 34 (n = 110), and 38 (n = 91) of pregnancy at which fasting blood samples were collected for fatty acid and immunological analysis, and a food frequency questionnaire (FFQ) was administered (at 20 and 34 weeks). At delivery, placenta and umbilical cord tissue were collected for fatty acid analysis. Mothers were followed-up at 3 months postpartum when the FFQ was administered (n = 88). Maternal plasma, peripheral blood mononuclear cell (PBMC), placenta nad umbilical cord tissue fatty acid compositions were determined by gas chromatography (GC). Maternal immune cell subsets were determined by flow cytometry (FACS); ex-vivo cytokine production by PBMC in response to stimulants (allergens, mitogen, and toll-like receptor (TLR) ligands) was determined by cytometric bead array (CBA) and FACS; and eicosanoid (prostaglandin (PG) E2) production by PBMC was determined by enzyme-linked immunosorbent assay (ELISA). Subjects complied with the salmon intervention and this increased their intakes of EPA, DHA, vitamin D and selenium. The salmon intervention prevented the pregnancy-associated depletion in LC n-3 PUFA and resulted in higher LC n-3 PUFA status in maternal plasma, maternal PBMC, placenta and cord tissue. Effects of pregnancy on many of the immune parameters assessed here were identified. However, the salmon intervention had only limited impact on maternal immunity as measured here, and thus it cannot be concluded whether the intervention would have an effect on the immune system of the offspring

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37

Zhang, Yan. "Comparison of Functional Porous Organic Polymers (POPs) and Natural Material Zeolite for Nitrogen Removal and Recovery from Synthetic Urine." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7657.

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Urine comprises around 1% of domestic sewage volume but holds 80% of total nitrogen. Source separation is a sustainable way to wastewater management than traditional way due to low energy cost and preventing certain pollutants into wastewater treatment plants. Currently, removing and recovering nitrogen from source-separated urine has attracted more and more interests. Of them, ion exchange was used for removal and recovery of nitrogen in the form of ammonia from synthetic urine for potential application as a fertilizer in agriculture. No previous research studies were conducted to investigate the removal and recovery of nitrogen from hydrolyzed urine by ion exchange using POPs (porous organic polymers). So this study focused on evaluating the performance of POPs and comparing with clinoptilolite in synthetic hydrolyzed urine in terms of adsorption capacity (isotherm), adsorption rate (kinetics), regeneration rate, and cost. The ammonium removal from hydrolyzed urine using POPs was rapid with a high capacity of 68.03 mg/g than clinoptilolite (15.36 mg/g), and the regeneration efficiency of clinoptilolite and POPs can achieve 91% and 95.3%, respectively based single time use result. Although POPs had the better performance at one time use and multiple times use, it also had high materials cost. Additionally, the capacity of POP was estimated using the integrated ion exchange regeneration process model as 30.24 mg/g and 28.65 mg/g on cycle 10 and cycle 24, respectively. The regeneration efficiency of POPs was predicated as 45.4% and 38.4% in cycle 10 and cycle 24, respectively. The predicted capacity decreased with the number of cycles, but remained at about 55% of virgin POPs after 24 cycles, indicating POPs can maintain good performance after multiple reuses than clinoptilolite.

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38

Silva, Juliana Brito da. "Micronutrientes em perfis de solos do Escudo Sul-riograndense." Universidade Federal de Pelotas, 2009. http://repositorio.ufpel.edu.br/handle/ri/1178.

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The highlands from the southern region of State of Rio Grande do Sul have been traditionally used for extensive cattle raising, which practically does not demand soil analysis and fertilization. The sustainable use of the soils with other agricultural activities, such as forestry, that has been increased in the last few years, needs a more suitable and accurate knowledge of the needs of soil fertilization, including the micronutrients. In this context, this study has the objective of quantifying the micronutrients availability and reserve present in the different types of soils of the region. For this purpose, 22 soil profiles representative of the different soil parent material and profile development found in the region were sampled and chemical analysis of the total, available and oxide bound Cu, Zn, B, Fe and Mn were performed. The results indicate that for the majority of the soils the available and total contents of micronutrients are high, with more likely deficiency possibilities for Cu and B, in this order, related to specific soil parent material types. For Zn and Mn, despite the high available contents, there is the possibility of deficiency in the future due to a low reserve in case the crop withdraw be not returned. The ammonium oxalate extracted Cu and Zn data indicate that the reserve of these micronutrients in low cristallinity Fe (and Mn) is negligible. Only a small fraction of the total Cu is found in oxides in the soils studied, in opposition to the Zn, where in a topsoil it reached around 65%.
As terras altas da região sul do estado do Rio Grande do Sul vêm sendo tradicionalmente utilizadas com pecuária extensiva, que praticamente não demanda análise e correção de solo. O uso sustentável do solo com outras atividades como a silvicultura, que começou a ser implantada em maior escala nos últimos anos, necessita de um conhecimento mais adequado com relação às necessidades de correção do solo, incluindo os micronutrientes. Nesse contexto, este trabalho tem como objetivo quantificar a disponibilidade e a reserva de micronutrientes presentes nos diferentes tipos de solos da região. Para tal, foram coletadas amostras de 22 perfis de solos representativos da variedade do material de origem e do grau de desenvolvimento dos solos presentes na região e realizadas análises químicas dos teores disponíveis, totais e ligados aos óxidos dos micronutrientes Cu, Zn, B, Fe e Mn. Os resultados indicam que para a maioria dos solos os teores disponíveis e a reserva são altos, com maiores possibilidades de deficiência de Cu e B, nessa ordem, em solos oriundos de materiais de origem específicos. No caso do Zn e do Mn, apesar dos teores disponíveis altos, em casos particulares, uma baixa reserva pode gerar possibilidade de deficiência desses micronutrientes no futuro. Os dados de Cu e Zn com oxalato de amônio indicam que a reserva dos micronutrientes Cu e Zn em óxidos de Fe (e de Mn) de baixa cristalinidade é inexpressiva. Nos solos estudados, apenas uma pequena fração do Cu total está presente nos óxidos, ao contrário do Zn onde essa chegou, em um determinado solo, a atingir 65%.

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Silva, Caroline Santos da. "Produção e avaliação de materiais de referência para nutrientes e contaminantes inorgânicos em amostras agronômicas." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/7860.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The intensive search for the reliability of results increases the role of reference materials, mainly in analytical chemistry, because they provide metrological references to ensure traceability of measurements and are still central to the validation of analytical methods. The increasing demand for new reference materials is gradual in all areas of knowledge, but the agricultural and food sectors are among the neediest. In Brazil, this requirement is met only by the import of the material at high costs, being frequently the lack of adequate material to the needs of the country. In this context, this work aimed at the production of reference material for inorganic nutrients and contaminants present in a phosphate rock, the raw material used to manufacture fertilizers. The material was produced by following the next steps, internationally established by ISO GUIDES 30 to 35: preparation and ackaging material, assessment of uniformity, stability test in short and long periods and in prior characterization that was the assembly of the collaborative trial, with the distribution of the prepared material to laboratories that were willing to collaborate with the project.Sample preparation studies also have been conducted, aimed at speed and reduced use of reagents. The evaluation of the estimated minimum mass, homogeneity, and stability of the material was performed using inductively coupled plasma optical emission spectrometry (ICP OES) as determination technique. Phosphorus determination was evaluated by laser-induced breakdown spectroscopy (LIBS).Analysis of single-factor variance (ANOVA) was applied to results and the homogeneity and stability of the material presented averages within the 95% confidence interval. The obtained resultsalong the prepare and with collaborative trialallowed the chemical characterization and the determinationof the uncertainties related to each stage of the preparation of the material, and final preparation of the chart control with results of the reference materialwith the expanded uncertainty for each of the analytes under study.Part of the work was developed by the National Research Council Canada (NRCC) in Ottawa in Canada.The applicability of the microwave-induced combustion for sample preparation of previously prepared national reference materials, bovine liver (RM-Agro E3001a) and forage (RM E1001a-Agro) was evaluated for the determination of As, Cd, Cu, and Pb by inductively coupled plasma mass spectrometry (ICP-MS), and the recults coulb be applied in other organic and inorganic materials.
A intensa busca por confiabilidade de resultados torna cada vez mais importante o papel dos materiais de referência, principalmente em química analítica, pois fornecem referências metrológicas visando assegurar a rastreabilidade de medições e ainda são fundamentais para a validação de métodos analíticos. O aumento da demanda por novos materiais de referência é gradativo em todas as áreas do conhecimento, porém os setores agropecuários e de alimentos estão entre os mais carentes. No Brasil, essa demanda é atendida somente pela importação do material a custos elevados, sendo freqüente a inexistência de materiais adequados às necessidades do país. Nesse contexto, o presente trabalho visou à produção de material de referência para nutrientes e contaminantes inorgânicos em fosfato de rocha, matéria-prima utilizada para a fabricação de fertilizantes. O material foi produzido seguindo as seguintes etapas, estabelecidas internacionalmente pelas ISO GUIAS 30 a 35: preparo e envase do material, avaliação da homogeneidade, teste de estabilidade a curto e a longos períodos e na caracterização prévia, que consistiu na montagem do ensaio colaborativo, com a distribuição do material preparado a laboratórios que se dispuseram a colaborar com o projeto. Ainda foram realizados estudos voltados ao preparo da amostra visando a rapidez e redução de uso de reagentes. A avaliação da estimativa da massa mínima, da homogeneidade e da estabilidade do material foi realizada utilizando-se como técnica de determinação a espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Para a determinação de fósforo foi avaliado o emprego de espectrometria de emissão com plasma induzida por laser (LIBS). Os resultadosforam submetidos à análise de variância e fator único (ANOVA) e a homogeneidade e a estabilidade do material apresentaram médias dentro do intervalo de confiança de 95%. Os resultados obtidos durante o preparo e através do ensaio colaborativo possibilitaram a caracterização química e o calculo das incertezas relativas a cada etapa do preparo do material, sendo elaborada a carta controle com os resultados do material de referência e as incertezas expandidas para cada um dos analitos em estudo. Parte do trabalho foi desenvolvido junto ao National Research Council Canada (NRCC) em Ottawa no Canadá, onde foi avaliada a aplicabilidade do sistema de combustão iniciada por radiação microondas no preparo de amostras de materiais de referência nacionais anteriormente preparados, fígado bovino (RM-Agro E3001a) e forrageira (RM-Agro E1001a), para a determinação de As, Cd, Cu e Pb por espectrometria de massas com plasma indutivamente acoplado (ICP-MS), sendo obtidos resultados que poderão ser aplicados em outros materiais orgânicos e inorgânicos.

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Clark, W. Andrew, Norman Assad, Tasha H. Ferrell, and Nicole S. Litwin. "Nutrient Intake, Oxidative Stress and Fatty Acid Profiles of Women with and Without Fertility Issues." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/2517.

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Faria, Obede Borges. "Utilização de macrófitas aquáticas na produção de adobe: um estudo de caso no reservatório de Salto Grande (Americana - SP)." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-10022003-103821/.

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Este trabalho busca otimizar a utilização de biomassa de macrófitas aquáticas na produção de adobe (tijolos de terra crua, secos ao sol), baseado na determinação e estudo de suas características físicas e mecânicas, assim como nas características físicas e químicas destas plantas. A pesquisa foi desenvolvida no reservatório de Salto Grande, no município de Americana - SP. Este lago está localizado em uma área com déficit de habitações de interesse social, apresentando altos índices de urbanização e industrialização, o que acarreta no seu avançado processo de eutrofização artificial, decorrente das ações antrópicas. As macrófitas aquáticas predominantes no reservatório (Brachiaria arrecta, Eichhornia crassipes e Pistia stratiotes) apresentam níveis elevados de metais pesados e nutrientes (nitrogênio e fósforo), o que torna inviável sua utilização como forragem ou fertilizante. A utilização desta biomassa em materiais de construção é aqui apresentada como uma alternativa de manejo integrado do lago, na forma de encapsulamento (ou solidificação / estabilização) destas substâncias químicas, além de possibilitar a autoconstrução de habitações de baixo custo. Uma outra função do uso da biomassa no adobe é a estabilização do solo, que apresenta alto teor de argila (59 %, com 21 % de silte e 20 % de areia, classificado como A-7-6 HRB) e sofreria grandes retrações durante o processo de secagem, com surgimento de fissuras excessivas e conseqüente redução de resistência mecânica dos tijolos. A adição da biomassa contribuiu com a redução destas fissuras e da massa específica dos tijolos. Os resultados demonstraram ser esta utilização perfeitamente viável, com expressiva retirada de biomassa (juntamente com os metais e nutrientes) do sistema, além de significativas melhorias na qualidade do adobe, tanto físicas como mecânicas. Em linhas gerais, Eichhornia crassipes se mostrou a mais eficiente neste aspecto. Além de tudo, os resultados da pesquisa mostram que, apesar do adobe ser talvez o mais antigo material de construção manufaturado, sua aplicação se mostra perfeitamente viável, numa perspectiva mais ampla de sustentabilidade, se apresentando como um material completamente ecológico e adequado para regiões tropicais.
This work intends to optimise the utilization of aquatic macrophyte biomass in the adobe (a sun-dried mud brick) production, based on the study of the physical and mechanical characteristics of these bricks and the macrophytes biomass estimate as well as their chemical characteristics. The research was developed in the Salto Grande Reservoir region, in Americana (a town in São Paulo State, Brazil). This lake is located in an area of high urbanization and industrialization level, with common dwelling deficit, which is in advanced artificial eutrophication process by human activity action. The aquatic macrophytes found in that place (Brachiaria arrecta, Eichhornia crassipes and Pistia stratiotes) present a high level of heavy metals and nutrients that make impracticable their utilization as forage or fertilizer. The biomass utilization in the construction of materials appears here as an alternative of integrated management of the lake in the stabilization/solidification (or encapsulation) of these chemical substances, in addition to the fact that it makes possible the self-building of low cost dwellings. The other biomass function is to stabilize the soil that has a high clay concentration (59%, with 21% silt and 20% sandy) and would suffer a large drawing back during the drying process, with the introduction of excessive fissures. This biomass addition was made to reduce these fissures and the specific mass of the bricks. Besides, the research results show that, even though the adobe bricks are perhaps the oldest manufactured building material, their application persists practicable mainly in the sustainability hopes for being a completely ecological building material and adequate for the tropical regions.

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Karunarathna, Mudugamuwe Hewawasam Jayan Savinda. "Photochemistry of iron(III) with carboxylate-containing polysaccharides for sustainable materials." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1586468303760847.

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Sanpera, Calbet Isis. "Global changes in headwater streams: effects of hydrological and nutrient fluctuations on the quality of basal resources = Canvis globals en rius de capçalera: efectes de les fluctuacions hidrològiques i dels nutrients en la qualitat dels recursos basals." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/145433.

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Streams are complex and highly diverse ecosystems. Within the stream network, headwater streams (1st to 3rd order) are highly important. Headwaters represent most of the total length, influence the structure and functioning of higher order streams, generate most of the water flow and support higher rates of biogeochemical processing, with a higher rate of nutrient removal. Moreover, they offer high habitat diversity, both within and among streams. From all the drainage basin, it is the riparian zone which has the greatest influence in the structure and functioning of these streams. The in-fall of vegetation and leaching from plant litter are major sources of energy for stream food webs. All energy available to consumers originates from primary producers from either out- or in-stream and food webs are fuelled by a complex mixture of allochthonous and autochthonous resources. In headwaters, allochthonous basal resources are generally larger than autochthonous energy sources. However, both the quantity and quality of allochthonous and autochthonous resources influence the stream structure and functioning. Quality of resources determines their potential nutritional value for the invertebrates feeding on them. The nutritional quality of organic matter (OM) can be assessed by measuring the elemental or biomolecule composition (polysaccharide, protein and lipid content). Lipids are the most efficient energy-storing compounds, and within lipids, fatty acids and sterols include essential molecules for consumers. In a context of global change, streams are highly affected by multiple direct and indirect anthropic impacts, such as climate change, land use changes and water course alterations, affecting hydrology and nutrient and light availability, which in turn affect the quality and quantity of basal resources. The aim of this thesis was to determine how environmental factors influence the quantity and quality (biochemical composition) of basal resources in headwater streams. Of the multiple environmental factors affected by global change, the present study focused on changes in hydrology and nutrient and light availability, with particular reference to headwater Mediterranean streams. This study has been mainly performed in Fuirosos, a Mediterranean stream in the northeast of the Iberian Peninsula, but also in the Mayfly creek artificial channels, in the Pacific Coast Mountains of Canada. Several methods were used, such as the measure of particulate and dissolved OM fluxes, elemental composition of OM, nutrient addition; chlorophyll content, bacterial density and extracellular enzymatic activities of biofilms, and the measurement of the biochemical quality of the basal resources. (i.e., epilithic and epipsammic biofilms, leaves and, transported particulate and dissolved OM). We have demonstrated that the El Niño Southern Oscillation (ENSO) affected riparian inputs to the stream through teleconnections that alter average precipitation (during El Niño periods, average annual precipitation was lower than in other periods, causing higher riparian inputs, due to the hydric stress of riparian trees while, during La Niña periods, precipitation was higher than at other times, leading to decreased riparian inputs). Drought periods caused a bimodal distribution of annual riparian inputs and reduced the quality of basal resources, whereas accumulated drought events diminished the riparian inputs. Floods decreased the benthic OM, increased the amount of transported OM and modified its quality. The addition of nutrients led to a decrease in carbon content, and higher light availability led to a decrease in protein content of allochthonous resources. Biofilm quality was generally higher with the addition of nutrients when light availability was higher. We consider that the nutritional quality of basal resources is a complex parameter. Whilst elemental and biochemical composition can sometimes be related, knowledge on the latter enables a better understanding of the mechanism by which abiotic changes affect the quality of resources. However, the complexity of measuring elemental composition, biochemical composition and fatty acid composition gradually increases. Hence, we suggest that the choice of the indicators of quality used would depend on the goal of the study that want to be performed and on the trade-off between analysis effort and information that wants to be obtained. Because food webs are fuelled by a complex mixture of allochthonous and autochthonous resources, the quantity and quality of these resources are limiting factors for stream secondary production. Hence, the changes observed in this study, will probably affect stream food webs.
Els rius són ecosistemes complexes i molt diversos. Dins la xarxa fluvial, les rius de capçalera (de 1er a 3er ordre) tenen una gran importància. Els rius de capçalera representen la major part de la longitud total, influencien l’estructura i el funcionament dels rius d’ordre més gran, generen la major part del cabal i donen suport a taxes altes de processament biogeoquímic, amb una alta taxa d’eliminació de nutrients. A més a més, contenen un gran diversitat d’hàbitats, tant dins dels rius com entre ells. De tota la conca, és la zona ripària la que té una més gran influència en l’estructura i el funcionament d’aquests rius. La caiguda de la vegetació i el lixiviat de les fullaraca són importants fonts d’energia per les xarxes tròfiques. Tota l’energia disponible pels consumidors prové dels productors primaris tant de dins com de fora del riu i les xarxes tròfiques estan sustentades per una complexa barreja de recursos al•lòctons i autòctons. En els rius de capçalera, els recursos basals al•lòctons són generalment més importants que les fonts d’energia autòctones. Tot i això, tant la quantitat com la qualitat dels recursos al•lòctons i autòctons influencies l’estructura i el funcionament d’aquests rius. La qualitat dels recursos determina el seu valor nutritiu potencial pels invertebrats que s’alimenten d’ells. La qualitat nutritiva de la matèria orgànica (MO) es pot ser avaluada mesurant la composició elemental o de biomolècules (contingut de polisacàrids, proteïnes i lípids). Els lípids són els components d’emmagatzematge d’energia més eficients, i dins dels lípids, els àcids grassos I els esterols inclouen molècules essencials pels consumidors. En un context de canvi global, els rius estan afectats de forma molt important per múltiples impactes antròpics directes i indirectes, tals com el canvi climàtics, els canvis d’usos del sòl i les alteracions dels cursos fluvials; els quals afecten la hidrologia i la disponibilitat de nutrients i llum, els quals al seu torn, afecten la quantitat i la qualitat dels recursos basals en els rius de capçalera. Dels múltiples factors ambientals afectats pel canvi global, aquest estudi es centra en els canvis en la hidrologia i la disponibilitat de llum i nutrients, en particular als rius de capçalera Mediterranis. Aquest estudi ha estat realitzat principalment a Fuirosos, un riu Mediterrani al nord-est de la Península Ibèrica, però també als canals artificials de Mayfly creek, a les muntanyes de la costa Pacífica de Canadà. En aquest estudi s’han utilitzat diversos mètodes, tal i com la mesura dels fluxos de MO particulada i dissolta, la composició elemental de la MO, l’addició de nutrients; el contingut de clorofil•la, la densitat bacteriana i les activitats enzimàtiques extracel•lulars del biofilm i la mesura de la qualitat bioquímica dels recursos basals (és a dir, els biofilms epilítics i epipsàmics, les fulles i la MO particulada i dissolta transportada). Hem demostrar que El Niño/Oscil•lació del Sud (ENOS) va afectar les aportacions ripàries al riu a través de teleconnexions que van alterar la precipitació mitjana (durant els períodes de El Niño, la precipitació mitjana anual era més baixa, provocant un augment de les aportacions ripàries, degut a l’estrès hídric dels arbres, mentre que durant els períodes de La Niña, la precipitació era més alta que en altres moments, portant a una disminució de les aportacions ripàries). Els períodes de sequera van causar una distribució bimodal de les aportacions ripàries anuals i van reduir la qualitat dels recursos basals, mentre que els episodis de sequera acumulats van provocar la disminució de les aportacions ripàries). Les avingudes van provocar la disminució de la MO bentònica, van augmentar la quantitat de MO transportada i van modificar la seva qualitat. L’addició de nutrients va portar a una disminució del contingut de carboni, i una disponibilitat més alta de llum va provocar una disminució del contingut de proteïnes dels recursos al•lòctons. La qualitat del biofilm era generalment més alta amb l’addició de nutrients quan la disponibilitat de llum era més alta. Considerem que la qualitat nutritiva dels recursos basals és un paràmetre complex. Tot i que la composició elemental i bioquímica poden estar relacionades en alguns casos, el coneixement d’aquesta última permet una millor comprensió dels mecanismes a través dels quals els canvis abiòtics afecten la qualitat dels recursos. Tot i això, la complexitat de mesurar la composició elemental, la composició bioquímica i els àcids grassos, augmenta gradualment. Així doncs, suggerim que la tria dels indicador de qualitat utilitzats dependrà de l’objectiu de l’estudi que es vulgui realitzar i en el balanç entre l’esforç d’anàlisi i la informació que es vol obtenir. Com que les xarxes tròfiques estan sustentades per una complexa barreja de recursos al•lòctons i autòctons, la quantitat i la qualitat d’aquests recursos són factors que limiten la producció secundària en el riu. Així doncs, els canvis observats en aquest estudi, afectaran probablement les xarxes tròfiques fluvials.

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Franzé, Rodrigo Vezzani. "Qualidade tecnológica e teores de nutrientes da cana-de-açúcar sob efeito de maturadores /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/96958.

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Resumo: O presente trabalho teve por objetivo avaliar o uso de diferentes produtos químicos como maturadores, em diferentes doses e misturas na qualidade tecnológica e também quantificar os teores de nutrientes nas lâminas foliares e no caldo da cana-planta cv. SP83-2847. O experimento foi conduzido na Fazenda São Francisco do Itaquerê, da Usina Santa Fé, Nova Europa, SP, Brasil de maio a julho de 2008. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e quatro repetições. Os 14 tratamentos principais foram testemunha; glifosato; Moddus; Curavial; fosfito de potássio; sugar plus e sugar super plus, em suas doses e misturas aplicados no dia 21/05/2008. As subparcelas constituíram-se em seis épocas de amostragens para análises tecnológicas (-1; 14, 28, 42, 56 e 70 dias após a aplicação - d.a.a.) e duas épocas para avaliação do teor de nutrientes nas lâminas foliares (LF) obtidas das folhas +1 e caldo de cana (28 e 56 d.a.a.). O uso de glifosato como maturador e em mistura com Moddus, fosfito de potássio e sugar pus apresentaram os melhores resultados tecnológicos, o mesmo observado com o uso do Curavial. Em função da maturação a quantidade de nutrientes na segunda época de avaliação foi significativamente menor principalmente no caldo. O uso do fosfito de potássio e do sugar super plus, nas dosagens de 2,0 L ha-1 e 2,5 L ha-1, respectivamente, não incrementaram a qualidade. No geral, os maturadores utilizados não alteraram a composição nutricional da cultivar SP83-2847, exceto para Mn e Fe nas lâminas foliares e de Fe e Cu no caldo
Abstract: This study aimed evaluate the use of chemical ripeners at different doses and blends in technological quality as well to quantify the sugarcane SP83-2847 leaves and juice mineral levels. The experiment was installed during the 2008/2009 season (May - July 2008) and carried out at "Fazenda São Francisco do Itaquerê" (farm), "Usina Santa Fé" (Sugar Mill), Nova Europa, SP, Brazil under a split-plot. The experiment design was the randomized blocks, in split-plot, with four replications. The 14 main treatments were control (only water); glyphosate; Moddus; Curavial; potassium phosphite; sugar plus, and sugar super plus. Their doses and mixtures were applied at 21st May 2008. The subplots were the sampling dates: -1; 14, 28, 42, 56 and 70 days after application (d.a.a.) and two samples to quantify mineral levels in the leaves and juice (28 and 56 days). The use of glyphosate as ripper and its blends with Moddus, potassium phosphite and sugar plus resulted in raw material technological quality improvement. The same effect was observed using Curavial. According to the ripening the nutrients amount at the second sampling date was significantly lower mainly in the juice. The potassium phosphite and sugar super plus use at 2.0 L ha-1 and 2.5 L ha-1, respectively, did not improve the technological quality. In general, the ripeners did not change the SP83-2847 sugarcane nutrition levels, except for Mn and Fe in the leaves and Fe and Cu in the juice
Orientador: Miguel Angelo Mutton
Coorientadora: Márcia Justino Rossini Mutton
Banca: Marcelo de Almeida Silva
Banca: Durvalina Maria Mathias dos Santos
Mestre

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Renman, Agnieszka. "On-site wastewater treatment : Polonite and other filter materials for removal of metals, nitrogen and phosphorus." Doctoral thesis, KTH, Mark- och vattenteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4811.

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Bed filters using reactive materials are an emerging technology for on-site wastewater treatment. Chemical reactions transfer contaminants from the aqueous to the solid phase. Phosphorus is removed from domestic wastewater by sorption to filter materials, which can then be recycled to agriculture as fertilisers and soil amendments. This thesis presents long-term column and field-scale studies of nine filter materials, particularly the novel product Polonite®. Phosphorus, nitro-gen and metals were removed by the mineral-based materials to varying degrees. Polonite and Nordkalk Filtra P demonstrated the largest phosphorus removal capacity, maintaining a PO4-P removal efficiency of >95%. Analysis of filter bed layers in columns with downward wastewater flow, showed that phosphorus, carbon and nitrogen content was vertically distributed, with de-creasing values from surface to base layer. Polonite and Filtra P accumulated 1.9-19 g P kg-1. Nitrogen in wastewater was scarcely removed by the alkaline filter materials, but transformation from NH4-N to NO3-N was >90%. Pot experiments with barley (Hordeum vulgare L.) revealed that after wastewater treatment, slags and Polonite could increase plant production. Batch experi-ments and ATR-FTIR investigations indicated that amorphous tricalcium phosphate (ATCP) was formed in the materials, so some of the accumulated PO4-P was readily available to plants. Low heavy metal contents occurred in the materials, showing that they can be applied as soil amend-ments in agriculture without contamination risks. A full-scale treatment system using Polonite as filter material showed an average PO4-P removal efficiency of 89% for a 92-week period, indicat-ing the robustness of the filter bed technology.
QC 20100907

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Ciuk, Karlsson Susanna. "Modeling of bark-, sand- and activated carbon filters for treatment of greywater." Thesis, Energi och Teknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-187078.

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ABSTRACT Modeling of bark-, sand- and activated carbon filters for treatment of greywater Susanna Ciuk Karlsson The part of the waste water produced in a household, originating from showers, dish - and wash water, is called greywater. It is possible to treat the greywater separately from the black water (toilet water) as it is less polluted and then use it for purposes such as garden irrigation. There are various methods for purifying greywater. Here, the possibility to purify greywater using three column filters with different materials (activated carbon, pine bark and sand) was examined through modeling in the computer program HYDRUS. A set-up with physical filters was available, where flow measurements were performed. These measurements were used to validate the model that was developed in HYDRUS. When a flow model had been produced that could replicate the measured flow, a module of HYDRUS was used to also model the reactive transport of nutrients and organic matter in the filters. The complete model was used for evaluation of the treatment performance of the filters during a default scenario where they were loaded with 1 liter of water per day containing pollutant concentration corresponding to typical greywater.
REFERAT Modellering av bark-, sand- och kolfilter för rening av BDT-vatten Susanna Ciuk Karlsson I ett hushåll används vatten som då blir till avloppsvatten. Detta avloppsvatten består till stor del av bad, disk och tvättvatten (BDT-vatten). Det är möjligt att behandla BDT-vattnet separat från klosettvattnet då det är mindre förorenat, låta det genomgå rening och sedan använda det för till exempel bevattning av trädgårdar. Det finns olika metoder för att rena BDT-vatten. Här studerades möjligheterna att rena BDT-vatten med hjälp av tre filter av olika material; aktivt kol, tallbark och sand, genom modellering i datorprogrammet HYDRUS. En praktisk experimentuppsättning med filterkolonner fanns att tillgå, där ett experiment med flödesmätningar genomfördes. Mätningarna användes för att validera modellen som utvecklades i HYDRUS. Efter att en flödesmodell som stämde överrens med uppmätta värden utvecklats, modellerades reaktiv transport av näringsämnen och organiskt material i filtren med en modul tillhörandes HYDRUS. Med hjälp av modelleringen kunde filtertypernas reningsförmåga utvärderas för ett iscensatt standardscenario där filtrena belastades med 1 l vatten/dag innehållandes föroreningar motsvarandes ett typiskt gråvatten.

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Swart, Etheresia, and Maryna Lehmann-Maritz. "Evaluation of near infrared reflectance (NIR) spectroscopy to determine the nutrient composition of raw materials and compound ostrich feeds." Thesis, Nelson Mandela University, 2017. http://hdl.handle.net/10948/13779.

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The chemical analysis of feed samples can be time consuming and expensive. The use of near infrared reflectance (NIR) spectroscopy was evaluated in a range of studies as a rapid technique to predict the chemical constituents in feedstuffs and compound ostrich feeds. The prediction of accurate results by NIR spectroscopy relies heavily upon obtaining a calibration set which represents the variation in the main population, accurate laboratory analyses and the application of the best mathematical procedures. This research project was designed to meet five objectives: The first objective was to determine the feasibility of using near infrared reflectance (NIR) spectroscopy to predict dry matter, ash, crude protein, crude fibre, oil content, and fatty acids such as palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) and linoleic acid (C18:2) in sunflower seed meal. The second objective was to develop calibration models to predict the dry matter, crude protein and oil content in milled canola seed, compared to whole canola seeds. The third objective was to investigate the feasibility of using NIR spectroscopy to predict the dry matter, ash, crude protein, crude fibre and oil content in milled lupin seeds, compared to whole lupin seeds. The fourth objective was to describe the development of near infrared reflectance (NIR) spectroscopy calibration equations for the prediction of chemical composition and amino acid content from different populations of alfalfa hay (Medicago sativa L.). The last objective was to determine the potential of NIR spectroscopy to predict the dry matter, ash, crude protein, crude fibre, ether extract, acid detergent fibre (ADF), neutral detergent fibre (NDF), calcium, phosphorus, in vitro organic matter digestibility (IVOMD) and amino acids such as lysine, methionine, threonine and arginine in compound ostrich feed samples. The results of this study indicate that NIR spectroscopy calibrations in sunflower seed meal are only applicable in sunflower breeding programmes for a fast screening as it was not suitable for prediction purposes. Screening of sunflower seeds by NIR spectroscopy represents a rapid, simple and cost effective alternative that is a great utility for users who need to analyse a large number of samples. Calibrations developed for crude protein and oil content in milled canola seeds proved to be better than calibrations for whole canola seeds. Although the results indicated that calibrations were better for milled canola seeds, it indicated values that were typical of equations suitable for screening purposes to select samples for more detailed chemical analysis. According to calibration statistics obtained for crude protein, crude fibre and oil content in whole lupin seeds, there is no need to grind the seeds to scan the meal as similarly accurate results were obtained by analysing whole seeds. Screening of whole lupin seeds by NIR spectroscopy represents a rapid, simple and cost effective alternative that may be of great utility for users who need to analyse a large number of samples with no sample preparation. The calibration and validation statistics obtained in the study to test the potential of NIR spectroscopy to predict the chemical composition and amino acid contents in alfalfa hay, showed the accuracy was too low for routine analysis, although NIR spectroscopy could be used as a screening tool. Further research needs to be done to improve the accuracy of the NIR spectroscopy analysis, including more samples from different cultivars and years. In the study to examine the possibility of using NIR spectroscopy to predict the chemical composition of compound ostrich feeds, the results indicated that NIR spectroscopy is a suitable tool for a rapid and reliable prediction of the crude protein, crude fibre, ether extract, IVOMD, ADF and NDF in compound ostrich feeds. Calibrations can be improved for amino acids if a larger sample pool is used to develop the calibrations. These studies indicated that NIR spectroscopy can be a rapid and successful tool for the prediction of the nutritive value up to certain amino acid contents of feedstuffs and compound ostrich feeds.

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48

Morris, Rebecca Kate. "A quantitative investigation of the crop yield response and nutrient value of treated biosolid materials used in agricultural production." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429601.

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49

Franzé, Rodrigo Vezzani [UNESP]. "Qualidade tecnológica e teores de nutrientes da cana-de-açúcar sob efeito de maturadores." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/96958.

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Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-23Bitstream added on 2014-06-13T18:57:49Z : No. of bitstreams: 1 franze_rv_me_jabo.pdf: 1078770 bytes, checksum: b9f6e8252d0d7eae11c88593967dfec8 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Usina São Martinho
O presente trabalho teve por objetivo avaliar o uso de diferentes produtos químicos como maturadores, em diferentes doses e misturas na qualidade tecnológica e também quantificar os teores de nutrientes nas lâminas foliares e no caldo da cana-planta cv. SP83-2847. O experimento foi conduzido na Fazenda São Francisco do Itaquerê, da Usina Santa Fé, Nova Europa, SP, Brasil de maio a julho de 2008. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e quatro repetições. Os 14 tratamentos principais foram testemunha; glifosato; Moddus; Curavial; fosfito de potássio; sugar plus e sugar super plus, em suas doses e misturas aplicados no dia 21/05/2008. As subparcelas constituíram-se em seis épocas de amostragens para análises tecnológicas (-1; 14, 28, 42, 56 e 70 dias após a aplicação – d.a.a.) e duas épocas para avaliação do teor de nutrientes nas lâminas foliares (LF) obtidas das folhas +1 e caldo de cana (28 e 56 d.a.a.). O uso de glifosato como maturador e em mistura com Moddus, fosfito de potássio e sugar pus apresentaram os melhores resultados tecnológicos, o mesmo observado com o uso do Curavial. Em função da maturação a quantidade de nutrientes na segunda época de avaliação foi significativamente menor principalmente no caldo. O uso do fosfito de potássio e do sugar super plus, nas dosagens de 2,0 L ha-1 e 2,5 L ha-1, respectivamente, não incrementaram a qualidade. No geral, os maturadores utilizados não alteraram a composição nutricional da cultivar SP83-2847, exceto para Mn e Fe nas lâminas foliares e de Fe e Cu no caldo
This study aimed evaluate the use of chemical ripeners at different doses and blends in technological quality as well to quantify the sugarcane SP83-2847 leaves and juice mineral levels. The experiment was installed during the 2008/2009 season (May – July 2008) and carried out at “Fazenda São Francisco do Itaquerê” (farm), “Usina Santa Fé” (Sugar Mill), Nova Europa, SP, Brazil under a split-plot. The experiment design was the randomized blocks, in split-plot, with four replications. The 14 main treatments were control (only water); glyphosate; Moddus; Curavial; potassium phosphite; sugar plus, and sugar super plus. Their doses and mixtures were applied at 21st May 2008. The subplots were the sampling dates: -1; 14, 28, 42, 56 and 70 days after application (d.a.a.) and two samples to quantify mineral levels in the leaves and juice (28 and 56 days). The use of glyphosate as ripper and its blends with Moddus, potassium phosphite and sugar plus resulted in raw material technological quality improvement. The same effect was observed using Curavial. According to the ripening the nutrients amount at the second sampling date was significantly lower mainly in the juice. The potassium phosphite and sugar super plus use at 2.0 L ha-1 and 2.5 L ha-1, respectively, did not improve the technological quality. In general, the ripeners did not change the SP83-2847 sugarcane nutrition levels, except for Mn and Fe in the leaves and Fe and Cu in the juice

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50

Borgestedt, Helena, and Ingela Svanäng. "Towards Sustainable Phosphorus Management : Material Flow Analysis of phosphorus in Gothenburg and ways to establish nutrient recycling by improving urban wastewater systems." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-159721.

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All life forms require the nutrient phosphorus and it cannot be substituted by any other element. The global cycle of phosphorus is special among the major biogeochemical cycles, since it has no significant gaseous compounds and only closes every 10-100 million years. However, human activities, as application of mineral fertilizers, conversion of natural ecosystems to arable land and releases of untreated waste, intensify remarkably thephosphorus flows. The problems with linear flows of a limited resource leading to eutrophication of aquaticenvironments, for instance, have generated national environmental quality objectives for phosphorus in Sweden. The main objective of this master thesis is to get a holistic overview of how phosphorus is moving through Gothenburg today, using Material Flow Analysis as method. The spatial system boundary is the municipality of Gothenburg and the temporal system boundary is the year of 2009. One way of dealing with the linear flows ofphosphorus might be to develop the wastewater systems used in Gothenburg today. Possible changes in phosphorus flows, if kitchen grinders or urine-diverting toilets were installed in Gothenburg, are evaluated. In order to make the phosphorus management more sustainable, the linear flows have to be closed to a larger extent than today. One way towards this ambition is to emphasize other fertilizers than the mineral ones, like urine and low-contaminated sludge. The MFA shows that the absolutely largest input of phosphorus to Gothenburg is via the food. The two large outputs of the same magnitude are the digested sludge from the wastewater treatment plant of Rya and the ashes from the waste-fuelled district heating power plant of Sävenäs. About 7% of the phosphorus input to Gothenburg continues into the aquatic environment. According to this study, urine diversion and separate collection of food seem prospective in order to decrease the phosphorus flows in digested sludge from the wastewater treatment plant, ashes and aquatic deposition. An additional advantage would be generation of recycled fertilizing products with good quality.
Näringsämnet fosfor är nödvändigt för alla levande organismer och kan inte ersättas av något annat grundämne. Den globala fosforcykeln är speciell då den inte innehåller några gasformiga föreningar och sluts var 10-100 miljonte år. Användning av konstgödsel, omvandling av tidigare orörda ekosystem till odlingsmark och utsläppav förorenat avfall är exempel på mänskliga aktiviteter som intensifierar fosforflöden. Problemet med att linjäraflöden av denna begränsade resurs leder till övergödning av vattenmiljöer har genererat nationella miljömål i Sverige för fosfor. Det huvudsakliga målet med detta examensarbete är att få en översikt av hur fosfor rör sig genom Göteborg idag med hjälp av substansflödesanalys. Den rumsliga systemgränsen är kommungränsen för Göteborg och den tidsmässiga avgränsningen är året 2009. Ett sätt att förbättra de linjära fosforflödena kan vara att utveckla deavloppssystem som idag används i Göteborg. Förändringarna som uppstår i fosforflödena vid installation av urinsorterande toaletter alternativt köksavfallskvarnar undersöks. Linjära flöden måste bli återcirkulerade i en högre utsträckning än idag ifall fosforhushållningen ska gå mot hållbarhet. Ett sätt att nå denna ambition är att lyfta fram andra gödselprodukter än konstgödsel, exempelvis urin och renare slam. Flödesanalysen visar att det definitivt största inflödet av fosfor till Göteborg är via livsmedel. De två största fosforutflödena, båda i samma storleksordning, är rötat slam från Ryaverket och aska från sopförbränningsanläggningen Sävenäs. Cirka 7% av den fosfor som flödar in i Göteborg fortsätter vidare ut i vattenmiljön. Enligt denna studie verkar urinsortering och separat insamling av matavfall vara goda lösningar för en framtid med mindre fosfor i slammet från Rya och i aska samt till vattenmiljön. En ytterligare fördel skulle vara erhållandet av hållbara gödselprodukter med god kvalitet.

This master thesis has also been published as a technical report at Chalmers with Report No. 2011:124.

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Dissertations / Theses on the topic 'Maternal nutrients'

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