Conflict has been rife in the Democratic Republic of Congo (DRC) for many decades, in a war over minerals. The economic incentive for this conflict lies in the multimillion dollar trade in conflict minerals, and the results are human rights abuses, violent conflict and corruption. International industries from resource-rich countries play a role in business and human rights violations in other countries where governance is weak, such as the DRC. The focus of this study is minerals extracted from the eastern DRC – the ores that produce tin, tantalum, tungsten (the 3Ts) and gold. These minerals are essential to the electronics industry, where various companies, primarily publicly listed companies, use these minerals in their production processes. This study examines the way in which companies at the top of the minerals supply chain use their buying power to influence their suppliers, exerting pressure down the supply chain. There have been dramatic changes in this arena recently, including the passing of conflict minerals legislation in the United States of America (USA) and an evolving multilateral architecture for supply chain due diligence emanating from the United Nations (UN) and the Organization for Economic Cooperation and Development (OECD). This study explores a variety of efforts initiated by a number of companies, governments and non-governmental organisations (both in the DRC and internationally) committed to combating conflict minerals. These efforts are aimed at formulating a regulatory framework on the security exchanges in Africa. Such a system should be conceptualised to regulate the due diligence process relating to minerals to enable end-users to trace supply chains from companies who use these minerals back to the sources of origin, by using independent audit chains of custody in a certification scheme similar to the Kimberley Process for conflict diamonds. This system is intended to be a means to strengthen the global transparency and accountability of electronics companies, together with industry initiatives, the OECD’s guidelines and extractive industry transparency initiatives principles, targeting publicly listed companies. This study, which consisted of a desktop review of books, journals, reports and internet sources, analyses elements of the USA‘s Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (Dodd-Frank Act) and South Africa’s King Code Report III on Corporate Governance of 2009 to determine whether these instruments are appropriate to be applied to African exchanges. It examines whether these instruments can be used to create a system requiring companies trading in or using conflict minerals in their production to compile an annual report that is to be made publicly available, disclosing the source and chain of custody of conflict minerals which originate from conflict zones, notably the DRC and other African countries. Due to the globalised markets, companies are gaining greater power than some governments. Companies are regulated by the legislation of the host country in which they are incorporated. The countries in which these companies operate and publicly trade are usually developing countries, which are characterised by impoverished communities and unstable or emerging democracies. The recent passing of the conflict minerals provisions in the Dodd-Frank Act requires that publicly traded companies in electronics industries report annually to the Securities Exchange Commission (SEC) on whether conflict minerals are part of their supply chains, and if so, what the steps have been taken to ensure that the companies do not contribute to the ongoing conflict. The practical/managerial implications of the African system is that the inconsistencies and instability in these emerging markets legislation and their relaxed rule of law create loopholes in the systems of industry which would normally require adherence to human rights principles and industry’s assistance in developing global standards and/or incorporating such standards into legislation. Industry is still largely unaware of whether products are conflict-free and has no way of determining the status of products. Responsible supply chain co-operation is therefore needed by companies to take steps to trace supply chains, and ensure independent auditing and certification. This study looks at how industry and governments can formulate international standards and regulations that require publicly listed companies using the 3Ts and gold in the production of their goods to put human rights at the heart of their enterprises. The findings of the study highlight the urgent need for due diligence, transparency and an accountability agenda for resource sectors. The study argues that more African states need to buy into these initiatives. Greater transparency must be part of broader governance schemes. The study recognises the important role of stock exchanges and the importance of regulating companies which trade and source minerals from the DRC and other countries in Africa. The study recommends a reform of securities exchanges and the implementation of corporate governance codes. The study argues that Africa can incorporate elements of the Dodd-Frank Act, the SEC Act, King III and the JSE Listing Requirements into national legislation in the individual states to impose important legal duties on companies to promote fairness, accountability, responsibility and transparency. Passing legislation to regulate the international minerals trade is crucial for the promotion of a legal mineral trade. / Dissertation (LLM)--University of Pretoria, 2013. / Centre for Human Rights / unrestricted

Inledning: Surdegsbrödet kom till Centraleuropa för cirka 5000 år sedan och har traditionellt sett bakats på fullkornsmjöl. Under 1900-talets gång har bröd bakat på bagerijäst och siktat mjöl kommit att dominera marknaden, men intresset för traditionella fermenteringsmetoder och fullkornsmjöl har på senare tid ökat. Fullkornsvetemjöl innehåller alla delar av sädeskornet och det är i skalet som de högsta halterna av fytinsyra återfinns. Fytinsyra är den vanligaste lagringsformen för metaller i spannmål. När fytinsyra kommer i kontakt med vatten sker en protolys och den ändrar då form till en anjon och kallas då fytat som är en stark komplexbildare till ett flertal katjoner. Människor kan inte producera enzymet fytas som kan bryta ner fytat, vilket resulterar i att metallerna inte blir biotillgängliga för kroppen. Vid brödjäsning kan fytat brytas ner av mjölets egna fytas eller av mikrobiellt fytas. Syfte: Studiens syfte är att klargöra om surdegsjäsning är en effektivare fermenteringsmetod än jästjäsning för att minska fytathalterna i fullkornsbröd. Det undersöks även om det finns någon samvariation mellan fytathalterna och halterna av Ca, Fe, Cd och Pb för att ta reda på om fytathalten skulle kunna ha betydelse för metallernas biotillgänglighet. Metod: Fytatet extraherades ur degen för att sedan elueras genom anjonbytare, därefter mättes fytathalterna genom spektrofotometri. Metallhalterna analyserades med ICP-MS. Resultat: Resultaten visade på att surdegjäsning hade en effektivare minskning av fytat än jästjäsning. Surdegarna hade inga signifikanta skillnader mellan fytathalterna eller fytatminskning. Järn visade signifikant minskning över tid och samvariation med fytathalterna. Slutsats: Surdegsjäsning är effektivare fermenteringsmetod än jästjäsning om man vill minska fytathalterna, och surdegsjäsning i 21 timmar minimerar fytathalterna i degen. Järn hade samvariation med fytat, vilket tyder på att förtäring av surdegsbröd som jäst i 21 timmar skulle kunna bidra till järnintaget.

Selected outcrops of the Upper Devonian to Lower Carboniferous, Witteberg Group, Cape Supergroup were mineralogically and structurally analyzed. The study area is located approximately 30km northwest of Kirkwood and 10km south of Darlington Dam, Eastern Cape, South Africa. Strata predominantly consist of arenaceous Witpoort Formation, which includes the Perdepoort, and Rooirand Members. The Perdepoort Member is a thinly bedded quartzite also known as the "white streak". The Rooirand Member quartzite is a highly iron stained red-brown quartzite. The dark-grey, pyritic rich shales of the Kweekvlei Formation overlie the Witpoort Formation in the southern half of the study site. These shales are highly deformed and display closely spaced thrust faults and close folds. The study area encapsulates a range of folding from tight to open folds. Faulting consists of low angle north verging thrust fault, south verging back thrusts, south and north dipping normal faults, and strike-slip faults. Closely spaced, fore-land verging thrusts faults predominate over hinterland verging back thrusts. Normal faulting post-dates thrust faulting and utilized weaknesses in axial planar cleavage and in certain instances existing thrust fault planes. Strike-slip faulting post-dates thrusting and has in places reactivated pre-existing thrust fault planes. Macro scale folding includes overturned synclines and large anticlines which have been eroded, exposing older strata. Fold axes plunge at low to moderate angles west-southwest. This correlates with tension gashes which indicate north westward directed forces. Eastward directed forces are confirmed by the presence of tension gashes and strike-slip movement. The local geology displays north westward directed compression followed by strike-slip movement. Normal faulting post-dates all other structures and is associated with the Mesozoic break-up of Gondwana. The Perdepoort Member was sampled along strike, at different outcrop latitudes. Seven samples were selected for scanning electron microscope analysis. Samples are composed almost entirely of quartz; accessories include, biotite, muscovite, sericite, baryte, and apatite. Epigenetic hematite is present along cracks within certain samples Epigenetic hematite occur along cracks with oxides and phosphates in the form of rutile, apatite and monazite present in a number of samples. When compared to other silica extraction operations the Perdepoort Member appears viable for explotation. However, for the solar cell industry the purity of this horizon is clearly far below that required for industy.

Downhole sampling of unboiled liquid at 1350 and 1500 m depth in the seawater-dominated Reykjanes high-temperature geothermal system in Iceland shows that metal concentrations measured at surface are minimum values due to mineral precipitation in the wells; by analogy of similar tectonic setting, host rocks and fluid composition, the metal concentrations measured in many black smoker vents at the seafloor are also minima. Fluids in the Reykjanes geothermal system react with mid-ocean ridge basalt at temperatures as high as 346°C and contain Fe 9-140 ppm, Cu 14-17 ppm, Zn 5-27 ppm, Pb 120-290 ppb, 1-6 ppb Au, and 28-107 ppb Ag. Fluids discharged at surface from the same wells have orders of magnitude lower metal concentrations due to precipitation caused by boiling and vapor loss during depressurization. Upstream of the orifice plate at high pressure (40 bar, 252°C) the precipitates consist mainly of sphalerite and chalcopyrite with a trace of galena and bornite. At the orifice plate of old wells, the pressure decreased sharply to 11 bar (188°C), resulting in abundant deposition of amorphous silica together with minor sphalerite and traces of chalcopyrite. In new wells the pressure at the orifice plate decreases to 22 bar (220°C); this pressure decrease and concomitant boiling causes deposition of fine-grained bornite-digenite solid solution together with sphalerite and galena on the fluid flow control valve. In high-pressure wells (average wellhead pressure 45-35 bar) most metals (mainly as sphalerite) are deposited downstream of the orifice plate, with up to 950 ppm Au and 2.5 wt.% Ag. Bulk concentrations in the scales vary between 15-60 wt.% upstream and downstream of the orifice plate and diminish from there. Iron increases up well from 8 to ~20 wt.% and decreases downstream of the orifice plate from 6 to 2 wt.% at the separation station; Cu downhole is ~3 wt.% but increases to 25 wt.% on the fluid flow control valve and then decreases; Pb downhole 100s ppm but at the wellhead is ~3 wt.%, increasing to 15 wt.% at the fluid flow control valve, then decreasing sharply from there.

Lithium is one of the most strategically important minerals at the time of writing. The demand for lithium and lithium compounds to be used in lithium-ion batteries is increasing day by day. Zimbabwe possesses a considerable resource of lithium ore, estimated at 23 000 mt Li. Beneficiation of this lithium ore could indeed be a very promising business in the near future. This work focuses on processing of petalite concentrate from the Bikita deposit in Zimbabwe for production of Li2CO3, with subsequent preparation of LiF and LiCl. Analysis performed on the petalite showed that the average Li2O content is 4.10 %. The extraction method used involves roasting the pre-heated concentrate with concentrated H2SO4 followed by water leaching of the resulting Li2SO4, solution purification and precipitation of Li2CO3 with subsequent preparation of LiF and LiCl. Investigation of the roasting and leaching showed that the dissolution rates are significantly influenced by roasting temperature and stirring speed. 97.3 % optimum rate of extraction was attained at 320 rpm and roasting temperature of 300 C. Water-washed lithium carbonate with a purity of 99.21 %( metal basis) and an average particle size of 1.4 ìm was produced. Good quality LiF and LiCl can be produced with purity of 99.36 % and 99.02 % respectively. The pH, concentration and agitation have a great influence on the morphology of the precipitated LiF. Lower pH values and optimum concentration of the Li2CO3 solution results in smaller particle size. High recovery of 96.53 % LiF was realised. Anhydrous LiCl was found to absorb moisture when exposed to air at ambient temperature. The synthesised LiCl melts at 606.2 C with a corresponding enthalpy of fusion of 18.4 kJ mol-1, close to the values reported in the literature. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Chemical Engineering / unrestricted

Orientador: Helena Teixeira Godoy / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade Engenharia de Alimentos / Made available in DSpace on 2018-08-04T01:18:33Z (GMT). No. of bitstreams: 1 Miranda_LucileneSoares_D.pdf: 1006638 bytes, checksum: 8fcf9b18416304ecfe4d7daaf5314935 (MD5) Previous issue date: 2004 / Resumo: O enriquecimento de alimentos com vitaminas e minerais atualmente é uma prática bastante difundida, permitindo melhorar o valor nutricional dos alimentos ou repor os nutrientes perdidos durante o processamento e/ou estocagem. Entretanto, alguns nutrientes podem sofrer interação negativa durante a vida de prateleira do alimento, como a do ferro (pró-oxidante) e as vitaminas A e E (antioxidantes). Portanto, estudos de interação e estabilidade de nutrientes e técnicas de análise eficientes e precisas são necessárias para garantir ao consumidor o consumo adequado de nutrientes e informações nutricionais seguras. No presente estudo objetivou-se avaliar a influência da adição de diferentes fontes de ferro na degradação do a-tocoferol acetato (TA) e do retinil acetato (RA) em leite desnatado UHT (Ultra Higth Temperature) e farinha de arroz enriquecidos, bem como o efeito do tipo de embalagem (permeável e não permeável à passagem de luz) e do processo de cocção convencional para a farinha de arroz e validar metodologia para análise simultânea destas vitaminas. O procedimento analítico consistiu na extração das formas vitamínicas com etanol, seguida de partição em hexano e limpeza com metanol:água (9:1). A fração do hexano foi evaporada e ressuspendida em etanol. Para a separação das vitaminas foi utilizada coluna C18 com sistema de eluição por gradiente, com fase móvel composta por metanol, água e tetrahidrofurano, a vazão de 1 ml/min. A detecção foi feita na região do UV, a 325 nm e 282 nm para a vitamina A e E, respectivamente. Os limites de detecção determinados foram de 1,3 ng/ml e 64,77 ng/ml, enquanto os de quantificação foram 2,6 ng/ml e 129,54 ng/ml para o retinil acetato e a-tocoferol acetato, respectivamente. A repetibilidade e a recuperação, em dois níveis de adição para as vitaminas, apresentaram valores entre 4,4 a 10,5% e media de 96%, respectivamente. Tanto na farinha de arroz quando no leite enriquecido para o RA não houve diferença significativa quando adicionou-se as fontes de ferro, enquanto a estabilidade do TA foi influenciado negativamente pela adição das formas químicas aminoácido quelato de ferro (Fe-AQ), sulfato ferroso (SF) e lactato de ferro (LF) na farinha e LF no leite desnatado. Para as farinhas, as embalagens utilizadas e o processo de cocção não influenciaram na perda relativa das formas vitamínicas estudas. A metodologia proposta e validada apresentou-se eficiente quando aplicada em leite desnatado e farinha de arroz enriquecidos. O enriquecimento da farinha de arroz com RA e TA e Fe de forma concomitante é mais indicado com ferro-ácido etileno-diamino tetraacético (Fe-EDTA) e ferro reduzido (FR) e o do leite desnatado com Fe-EDTA e Fe- AQ / Abstract: The food enrichment with vitamins and minerals is a very common practice nowadays, allowing to improve the nutritional value of the food and to replace nutrients lost during the processing and or stocking. However, the added nutrients can suffer negative interaction during rack life of the food, as it happens with iron (pro-oxidant) and vitamins A and E (antioxidant). Therefore, studies on interaction and stability of nutrients as well as efficient and precise analysis are necessary to guarantee to the consumer the adequate consumption of nutrients and correct nutritional information. This study aimed to evaluate the influence of the addition of iron from different sources in the degradation of a-tocopherol acetate (TA) and retinyl acetate (RA) in UHT (Ultra High Temperature) skim milk and in enriched rice flour packed in packing that allows and that does not allow light crossing, as well as conventional cooking and to validate a methodology for simultaneous analysis of these vitamins. The analytic procedure consisted in the extraction of the vitamins with ethanol, followed by partition in hexane and cleaning with methanol:water (9:1). The hexane fraction was evaporated and ressuspended in ethanol. For the separation of the vitamins a C18 column was used, with eluition system for gradient, with a mobile phase composed by methanol, water and tetrahidrofurane, in a flow of 1 ml/min. The detection was made in UV's Region of 325nm and 282nm to vitamin A and E, respectively. The limits of detection varied from 1.3 ng/ml to 64.77 ng/ml, while those of quantification were 2.6 ng/ml for retinyl acetate and 129,54 ng/ml for -tocopherol acetate, respectively. Repetibility and recovery, in two addition levels for the vitamins, showed values from 4.4 to 10.5% and measures of 96%, respectively. In the rice flour, as well as in the RA enriched milk, there was no significant difference for the added iron sources, while the stability of the TA was negatively influenced by the addition of the chemical forms Fe- AQ, SF and LF in the flour and LF in the skim milk. For the flours, the used packages and the cooking process did not influence the relative loss of the studied vitamin forms. The proposed and validated methodology showed to be efficient when applied in enriched skim milk and rice flour. The concomitant enrichment of rice flour with RA and TA and Fe showed to be better with Fe-EDTA and FR and the of skim milk with Fe-EDTA and Fe-AQ / Doutorado / Doutor em Ciência de Alimentos

Um dos sistemas de proteção de substratos metálicos mais comumente empregado na indústria é o de tintas. Os fatores favoráveis à utilização das tintas em pó incluem a não utilização de solventes, facilidades de processamento/aplicação e possibilidade de reaproveitamento do material que não aderiu na superfície da peça. As características térmicas, mecânicas e químicas da tinta são influenciadas principalmente pelo tipo de resina utilizada. As tintas em pó híbridas (epóxi/poliéster) visam conciliar a característica de resistência ao intemperismo e ação dos raios UV com as características de resistência química e mecânica. Nas tintas em pó podem ser adicionados nanocargas que tem por finalidade melhorar as propriedades térmicas, mecânicas e químicas dos revestimentos. Outra característica das nanocargas é o baixo custo financeiro, decorrente da utilização de uma menor quantidade de carga, com elevado nível de desempenho. Dentre as nanocargas utilizadas, pode-se citar a mica muscovita e a montmorilonita 30B (MMT 30B) que, quando incorporadas às tintas, mesmo em baixas concentrações, apresentam propriedades de barreira superiores que às cargas convencionais. Este trabalho tem por objetivo desenvolver e caracterizar uma tinta em pó híbrida contendo diferentes teores de mica muscovita e MMT 30B. Os argilominerais foram incorporados numa formulação padrão de tinta em pó híbrida nas proporções de 2, 4 e 6% (m/m), separadamente. Antes da aplicação da tinta, os substratos metálicos foram submetidos a um pré-tratamento de fosfatização com fosfato de zinco. Após isso, a tinta em pó foi aplicada em painéis com dimensões de 70 x 120 x 0,65 mm de aço carbono AISI 1010 através de pulverização eletrostática. Os argilominerais, a tinta em pó e o revestimento foram analisados empregando diferentes técnicas de caracterização, tais como análise granulométrica, análise termogravimétrica (TGA), calorimetria exploratória diferencial (DSC), espectroscopia de infravermelho por transformada de Fourier (FTIR) e microscopia eletrônica de varredura por emissão de campo (MEVFEG). O efeito da incorporação dos argilominerais nas propriedades físicas e de proteção à corrosão das tintas foi avaliado com ensaios de medida de brilho, aderência, flexibilidade, resistência ao impacto, impedância eletroquímica (EIE), exposição à névoa salina (NS) e ensaio de chama. Para todas as tintas contendo argilominerais foi constatado o aumento da dureza superficial e a redução de brilho com o aumento do teor do argilomineral, sendo este efeito mais pronunciado com a adição de 6% (m/m) de MMT 30B. A aderência da tinta ao substrato não foi alterada pela presença dos argilominerais. As tintas contendo mica muscovita apresentaram melhores resultados nos ensaios de resistência ao impacto e de flexibilidade quando comparados as tintas contendo MMT 30B, nas concentrações testadas. A amostra TH/6/MICA apresentou melhor resultado no ensaio de impedância eletroquímica em relação aos outros sistemas estudados. No ensaio de névoa salina todas as amostras apresentaram elevada proteção à corrosão. Não foram observados bolhas ou pontos de corrosão na superfície de nenhuma das amostras. Porém, no ensaio subsequente de migração subcutânea, a amostra TH/2/MMT 30B foi a que apresentou maior desplacamento. No ensaio de chama, as tintas com incorporação de mica muscovita apresentaram melhores resultados que as tintas com MMT 30B. Após a análise de todos os ensaios, conclui-se que a adição de mica muscovita na proporção de 4% resultou em uma tinta com melhores propriedades térmicas, mecânicas e químicas. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. / One of metallic substrates protection systems most commonly used in the industry is the paint. Factors favorable to the use of powder coatings include non-use of solvents, processing facilities/application and the possibility of reuse of material that did not adhere to the surface of the pieces. The thermal, mechanical and chemical characteristics of the obtained paint are influenced principally by the type of resin used. Hybrid (epoxy/polyester) powder coatings aimed at reconciling the weathering resistance characteristic and action of UV rays with the chemical resistance and mechanical characteristics. In the powder coatings can be added nanofillers which aims to improve the thermal, mechanical and chemical coatings. Another feature of nanofillers is the low financial cost resulting from the use of a lesser amount of filler, with a high level of performance. Among the nanofiller used, it can be cited muscovite mica and montmorillonite 30B (MMT 30B) that, when incorporated into the coatings, even at low concentrations, have higher barrier properties than conventional fillers. This work aims to develop and characterize a hybrid powder coating containing different amounts of muscovite mica and MMT 30B. Clayminerals have been incorporated in a standard formulation hybrid powder coatings in proportions of 2, 4 and 6% (w/w). Before applying the coating, the metal substrates were subjected to a pretreatment phosphating with zinc phosphate. After this, the powder paint was applied to panels with dimensions 70 x 120 x 0.65 mm carbon steel AISI 1010 through electrostatic spraying. The clayminerals, the powder paint and coating were analyzed using various characterization techniques, such as particle size analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), infrared spectroscopy in Fourier transform (FTIR) and scanning electron microscopy for field emission (SEM-FEG). The effect of the incorporation of clayminerals in the physical properties and corrosion protection of coatings was evaluated with brightness measurement tests, adhesion, flexibility, impact resistance, electrochemical impedance spectroscopy (EIS), exposure to fog saline (NS) and flame test. For all coatings containing clayminerals was found to increase the surface hardness of the coating and reduced gloss with increasing clay content, this being more pronounced effect with the addition of 6% (w/w) of MMT 30B. The adhesion of the coating to the substrate was not altered by the presence of clayminerals. The coatings containing mica muscovite showed better results in impact resistance tests and flexibility when compared to coatings containing MMT 30B. The sample TH/6/MICA showed better results in the electrochemical impedance test in relation to other systems studied. In the salt spray test all samples showed high corrosion protection. There were no blistering or corrosion spots on the surface of any of the samples. However, in the subsequent test of subcutaneous migration, the sample TH/2/MMT 30B showed the greatest peeling. In the flame test, coatings with incorporation of muscovite mica showed better results than coatings with MMT 30B. After analyzing all the tests, it is concluded that the addition of muscovite mica in the proportion of 4% resulted in an paint with improved thermal, mechanical and chemical properties.

Orientador: Wanilson Luiz Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-27T06:38:54Z (GMT). No. of bitstreams: 1 Volpato_Juliano_M.pdf: 8591527 bytes, checksum: 58b14d8c8d308419f349e7d957c88674 (MD5) Previous issue date: 2015 / Resumo: A existência de sedimentos altamente enriquecidos principalmente por Fe e P, provenientes das indústrias siderúrgica e de fertilizantes localizadas próximas ao estuário do rio Morrão, um dos principais receptores de efluentes industriais do Sistema Estuarino de Santos-Cubatão (São Paulo Brasil), juntamente com as condições físico-químicos do meio, constitui elementos especiais para avaliar se as condições formadoras de minerais como magnetita, hematita, pirita e vivianita podem ser influenciadas por contribuições químicas antrópicas. Este trabalho analisou as condições de formação desses minerais nos sedimentos superficiais do estuário do rio Morrão, na sua relação com a geoquímica dos sedimentos, condições físico-químicas, texturas sedimentares e conteúdo de matéria orgânica. A coleta de sedimentos de superfície consistiu em uma malha amostral de 10 x 10 m, em três transectos paralelos que cruzaram perpendicularmente o canal do rio Morrão. Os resultados mostraram que os sedimentos do rio Morrão encontram-se enriquecidos em diversos elementos químicos dentre os quais Fe, P, elementos terras raras (ETR) e vários metais-traço. O ambiente sedimentar do rio Morrão mostrou-se favorável à autigênese e coexistência de minerais como hematita, magnetita, pirita e vivianita. As fases minerais hematita e magnetita ocorrem amplamente no ambiente, já as fases minerais pirita e vivianita têm sua distribuição mais restrita. Os locais mais favoráveis à ocorrência de pirita e vivianita foram áreas de menor energia de fluxo, tais como planícies de intermaré lamosa, onde há altos teores de enxofre, ferro, fósforo, matéria orgânica e sedimentos finos / Abstract: The presence of sediments highly enriched by contaminant elements, mainly Fe and P, derived from a steel plant and fertilizer industries located near the Morrão River Estuary, the most anthropogenically influenced estuary of the Santos-Cubatão Estuarine System (São Paulo, Brazil), together with the environment physic-chemical conditions constitute special elements to evaluate if the forming conditions of mineral such as magnetite, hematite, pyrite and vivianite can be influenced by the anthropogenic input into the environment. This work studied the forming conditions of these minerals in the superficial sediments of the Morrão River Estuary in its relation with sediment geochemistry, physicochemical conditions, sedimentary texture, and organic matter content. The sample collection comprised a 10 by 10 meters grid composed of three parallel transects crossing perpendicularly the Morrão River channel. The results showed the sediments of Morrão River Estuary are enriched by several chemical elements among which Fe, P, REE and multiple trace elements. The sedimentary environment of the Morrão River showed to be propitious to the authigenesis and coexistence minerals such as hematite, magnetite, pyrite, and vivianite. Magnetite and hematite broadly occur in the environment, and pyrite and vivianite have restrict distribution. Moreover, the places more favorable to the pyrite and vivianite occurrence are areas with low water flux action, such as the intertidal mudflats, where concentrations of S, Fe, P, organic matter, and fine sediments are high / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

Orientador: Gabriela Alves Macedo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-27T13:41:19Z (GMT). No. of bitstreams: 1 Lima_FabiolaAliagade_D.pdf: 3830264 bytes, checksum: c4a5b890059ac6893391ad89b28572c4 (MD5) Previous issue date: 2015 / Resumo: Os ácidos fenólicos possuem propriedades biológicas que desempenham ação antioxidante, anti-inflamatória, antiproliferativa e antimicrobiana. Porém, esses fenólicos de cereais integrais podem ser difíceis de serem absorvidos totalmente pelo organismo, pois estão ligados a outros componentes da parede celular do vegetal ou a um antinutriente (taninos). O zinco, ferro e fósforo de grãos integrais são importantes para o desenvolvimento e manutenção do organismo. No entanto, os cereais ricos em fitato podem apresentar esses minerais complexados ao antinutriente e se tornarem indisponíveis para a absorção. Uma alternativa para melhorar a disponibilidade de ácidos fenólicos e minerais de cereais integrais é o tratamento enzimático. A tanase, tanino acil hidrolase (EC 3.1.1.20), é uma enzima com habilidade de atuar em ligações éster e depsídicas de taninos hidrolisáveis e já foi descrita como capaz de hidrolisar outros fenólicos como ácido tânico, ácido clorogênico, epigalocatequina, dentre outros. A fitase microbiana atua na desfitinização de cereais ricos em fitatos e sua ação melhora a bioacessibilidade de ferro e zinco na formulação infantil. A bioacessibilidade é uma alternativa aos ensaios 'in vivo' que apresentam alto custo de experimental, e pode ser medida pelo modelo de digestão 'in vitro'/absorção pelas células Caco-2. O objetivo deste trabalho foi verificar o efeito de tanase de 'Paecilomyces variotii' e fitase comercial, adicionadas à farinha de centeio, quanto ao teor de fenólicos totais e à identificação e quantificação por CLAE-DAD dos ácidos fenólicos; à capacidade antioxidante (DPPH, ORAC e FRAP); à disponibilidade de minerais (zinco e ferro); ao teor de antinutrientes (tanino hidrolisável e fitato); e à bioacessibilidade dos ácidos fenólicos da farinha. A tanase adicionada à farinha foi capaz de reduzir o teor de tanino hidrolisável, aumentar os fenólicos totais e potencializar a capacidade antioxidante. A farinha tratada com fitase apresentou menor teor de fitato e aumento no conteúdo de fósforo inorgânico proveniente da degradação enzimática. A disponibilidade de zinco e ferro, medida pela razão molar entre os minerais e o fitato foi melhorada após o tratamento da farinha com fitase. Foram identificados os ácidos ferúlico, sinápico e vanílico da farinha de centeio, que após o tratamento com a tanase apresentou aumento no teor de ácido ferúlico em cinco vezes em relação à farinha não tratada. Esse resultado evidencia a ação inédita da tanase de 'P. variotii' como possível feruloil esterase. A farinha biotransformada com tanase apresentou maior teor dos ácidos vanílico, ferúlico e sinápico, porém ao se avaliar a bioacessibilidade houve menor eficiência de transporte desses ácidos quando comparada à farinha controle. Provavelmente, a farinha biotransformada apresentou saturação desses fenólicos sobre a porção apical das células Caco-2 que reduziu a capacidade do transportador de ácidos monocarboxílicos (MCT1) nas duas horas de incubação. Isso corrobora com os resultados obtidos da exposição das células Caco-2 aos padrões de ácidos ferúlico e vanílico na concentração de 50 µl.ml-1 que apresentaram inibição da expressão gênica do MCT1. Contudo, o uso de enzimas como fitase e tanase na farinha de centeio é interessante, pois potencializa sua ação antioxidante, aumenta o teor de fenólicos, aumenta a disponibilidade de zinco e ferro, aumenta o conteúdo de fósforo e reduz os antinutrientes. Para trabalhos futuros seria relevante estudar o tempo de residência de ácidos fenólicos da farinha de centeio no ensaio de transporte celular, pois duas horas de incubação pode ter sido insuficiente para verificar todo o potencial da farinha tratada com tanase / Abstract: Phenolic acids have biological properties that perform antioxidant, anti-inflammatory, antiproliferative and antimicrobial. However, these phenolic of whole grains may be difficult to be completely absorbed by the body because they are connected to other cell wall components of plant or an antinutrient (tannins). Zinc, iron and phosphorus of whole grains are important for the development and maintenance of the organism. However, cereals rich in phytate may have these minerals complexed to antinutrient and become unavailable for absorption. An alternative to improve the availability of phenolic acids and minerals of whole grains is the enzymatic treatment. Tannase, tannin acyl hydrolase (EC 3.1.1.20) is an enzyme with the ability to act on ester bonds and depside bonds of hydrolysable tannins and has been described as capable of hydrolyzing tannic acid, chlorogenic acid, epigallocatechin, among others. Microbial phytase acts on dephytinization of cereals rich in phytate and its action improves the bioaccessibility of iron and zinc in infant formulation. Bioaccessibility is an alternative to in vivo tests that has expensive experimental cost, and can be measured by 'in vitro' model of digestion / absorption by the Caco-2 cells. The aim of this study was to investigate the effect of tannase Paecilomyces variotii and of commercial phytase added to rye flour, as to the total phenolic content and the identification and quantification by HPLC-DAD of phenolic acids; to the antioxidant capacity (DPPH, ORAC and FRAP); to the availability of minerals (zinc and iron); to the antinutrients content (phytate and hydrolyzable tannin); and as to bioaccessibility of phenolic acids of the flour. Tannase added to flour was able to reduce the hydrolyzable tannin content, increase total phenolic and enhance the antioxidant capacity. Flour rye treated with phytase decreased phytate content and increased content of inorganic phosphorus from enzymatic degradation. Availability of zinc and iron of the flour after treatment with phytase was improved, it was measured by the molar ratio between the mineral and phytate. Acids ferulic, sinapic and vanillic were identified and quantified of the rye flour, which after treatment with tannase showed an increase in ferulic acid content in five times bigger that the untreated flour. This result shows the tanase being an original action of 'P. variotii' as possible feruloyl esterase. Biotransformed flour rye with tannase showed a higher content of vanillic acid, ferulic and sinapic, however, when assessing the bioaccessibility was lower transport efficiency of these acids when compared to the control flour. Probably the biotransformed flour showed saturation of these phenolics about the apical portion of Caco-2 cells, they reduced the capacity of the monocarboxylic acids transporter (MCT1) within two hours of incubation. This corroborates the results of exposure of Caco-2 cells to standards of ferulic acid and vanillic at concentration of 50 ?l.mL-1, that showed inhibition of gene expression MCT1. However, the use of enzymes such as phytase and tannase in rye flour is interesting because it enhances antioxidant capacity, it phenolic content is incremented, availability of zinc and iron is bettered, increases the phosphorus content and reduces antinutrients. For further work, would be relevant the study of the residence time of the phenolic acids of rye flour on the cell transport assay, since two hours of incubation may have been insufficient to verify the full potential of flour treated with tannase / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos

Orientadores: Antonio Fernando Ribeiro, José Roberto Negrão Nogueira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-28T09:12:18Z (GMT). No. of bitstreams: 1 Hortencio_TaisDaieneRusso_D.pdf: 2122387 bytes, checksum: 6b337a8713273a2fcc11dbc17230038f (MD5) Previous issue date: 2015 / Resumo: Introdução O desenvolvimento da nutrição parenteral (NP) na década de 1960 e sua subsequente utilização na prática clínica tem tido um enorme impacto sobre os pacientes com numerosas doenças para as quais a nutrição foi impossível por outra via. Mas, esta nova tecnologia tem riscos associados, incluindo o desenvolvimento de distúrbios metabólicos, superalimentação e complicações infecciosas. Método Foram realizados dois estudos. O primeiro estudo teve como objetivo avaliar, em uma coorte histórica de pacientes pediátricos no Brasil que receberam NP individualizada e exclusiva, a prevalência de hipofosfatemia, hipocalemia e hipomagnesemia em até 48 horas antes do início da infusão de NP (P1), do 1° ao 4° dia (P2); 5° ao 7° dia (P3) e, investigar se a infusão de caloria e proteína e também a desnutrição foram relacionadas com esses distúrbios. O segundo estudo foi feito no Canadá. Trata-se de um estudo retrospectivo e multicêntrico, avaliando pacientes sob nutrição parenteral domiciliar (NPD), prospectivamente inseridos no Home Parenteral Nutrition Registry (HPN Registry) nos períodos: 2005-2008 ou 2011-2014. Mudanças na demografia, indicações para NPD, prescrição, avaliação nutricional, acesso vascular e número de infecção de cateter por 1000 dias de cateter foram avaliados. Resultados A desnutrição esteve presente em 32,8% dos 119 pacientes avaliados no primeiro estudo, 66,4% estavam em unidade de terapia intensiva pediátrica (UTI Ped), 13,5% morreram. O período de maior prevalência de distúrbios minerais foi o P1 54 (45,3%), no P2 = 35 (31,8%), no P3 = 4 (3,57%). Hipocalemia esteve relacionada à desnutrição OR 2,79 (95% CI 1,09-7,14) p = 0,045. Nos primeiros sete dias, foram infundidas calorias inferior à quantidade recomendada pelas recomendações atuais em até 84,9% dos pacientes e proteína adequada em até 75,7%. Proteína infundida acima da recomendação nos primeiros quatro dias foi relacionada com hypomagnesaemia OR: 5,66 (IC 95% 1,24 - 25,79) p = 0,033. No estudo canadense, comparando os períodos 2011-2014 com 2005-2008, as indicações para a NPD mudaram significativamente com o aumento da proporção de pacientes com câncer (37,9% versus 16,7%) e diminuição da síndrome do intestino curto (32% versus 65,5%). A taxa de infecção de cateter diminuiu de 1,58 para 0,97 por 1.000 dias de cateter; o uso de cateter tunelizado diminuiu de 64,3% para 38,0% e a proporção de cateteres centrais de inserção periférica (PICC) aumentou de 21,6% para 52,9%. Além disso, houve uma redução no número e dias de internações relacionadas à NPD, e mudanças na prescrição de energia, proteína e oligoelementos. Conclusão Hipofosfatemia, hipocalemia e hipomagnesemia foram eventos frequentes, sendo a individualização ferramenta primordial para gerenciá-los. Pacientes desnutridos tiveram maior chance de desenvolver hipocalemia e os que receberam proteína acima da recomendação tiveram mais chances de desenvolver hipomagnesemia. Os resultados sugerem uma mudança no perfil demográfico e acesso venoso no Canadá, com melhora na infecção de cateter, hospitalizações relacionadas à NPD, e prescrições / Abstract: Introduction: The development of parenteral nutrition (PN) in the 1960s and its subsequent use in clinical practice has had a huge impact on patients with numerous diseases for which nutrition was impossible by other route. But, this new technology has associated risks, including the development of metabolic disorders, overfeeding, and infectious complications. Methods We conducted two studies The first study aims to evaluate in a historical cohort of pediatric patients, the prevalence of hypophosphatemia, hypokalemia and hypomagnesaemia until 48th hours before beginning PN infusion (P1), from 1st¿4th day (P2); 5th¿7th day (P3) of PN infusion and, investigate if malnutrition, calories, and proteins infusion were correlated to these disorders. In Canada, a retrospective study evaluating patients who were prospectively entered in the registry either in 2005¿2008 or in 2011¿2014 was done. Changes in patient demography, indications for Home Parenteral Nutricion (HPN), regimen, nutritional assessment, vascular access, and number of line sepsis per 1000 catheter days were evaluated. Results Malnutrition was present 32.8% of 119 patients participants from the first study, 66.4% were in pediatric intensive care unit (PICU), 13.5% died. The P1 was the period of highest prevalence mineral disorders 54 (45.3%), P2 had 35 (31.8%) and, P3=4 (3.57%). Hypokalemia events were related to malnutrition OR 2.79 (95% CI 1.09-7.14) p = 0.045. In the first seven days, infused calories were below the amount recommended by current guidelines in up to 84.9% of patients and protein infused was adequate in up to 75.7%. Protein infused above recommendation was related to hypomagnesaemia OR: 5,66 (95% CI 1,24 ¿ 25,79) p=0,033. In 2011¿2014 compared with 2005¿2008, indications for HPN changed significantly with an increased proportion of patients with cancer (37.9% versus 16.7%) and decreased short bowel syndrome (32% versus 65.5%). The line sepsis rate decreased from 1.58 to 0.97 per 1,000 catheter days; tunnelled catheters decreased as the most frequently chosen vascular access method from 64.3% to 38.0% and the proportion of peripherally inserted central catheters (PICC) increased from 21.6% to 52.9%. In addition, there was a reduction in number, and days of hospitalizations related to HPN, and changes in the prescription of energy, proteins, and trace elements were noted. Conclusion Hypophosphatemia, hypokalemia and hypomagnesemia were frequent events, being individualization primary tool to manage them. Malnourished patients were more likely to develop hypokalemia, and patients receiving protein above the recommendation were more likely to develop hypomagnesemia. Results suggest a shift in patient demography and line access in Canada, with improvement in line sepsis, hospitalizations and HPN prescriptions / Doutorado / Saude da Criança e do Adolescente / Doutora em Ciências