Made available in DSpace on 2014-06-11T19:26:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-25Bitstream added on 2014-06-13T20:54:10Z : No. of bitstreams: 1 demore_ps_me_jabo.pdf: 1002271 bytes, checksum: a27ac944079c717a8ba5366fe7e35456 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O oídio em soja, trata-se de uma doença praticamente presente em todos os paises produtores. Os marcadores moleculares microssatélites ou SSR (Simple Sequence Repeat) têm sido amplamente utilizados no processo de seleção assistida de genótipos de soja. Assim, o objetivo deste estudo foi obter marcadores microssatélites próximos ao gene de resistência ao oídio em soja. O estudo foi realizado em duas populações F2, oriundas de cruzamentos entre parentais contrastantes quanto à resistência ao oídio. Para o estudo, foram selecionados marcadores microssatélites a uma distância de até 42 cM ao redor do gene Rmd (resistência ao oídio). Utilizou-se o método de BSA (Bulked Segregant Analysis) na avaliação dos marcadores, para a comparação com a análise fenotípica das populações. Na análise foram utilizados dez iniciadores SSRs para as duas populações, sendo identificados quatro marcadores polimórficos para o cruzamento 1 (MGBR95-20937 x IAC-Foscarin 31) e três para o cruzamento 2 (MGBR 46/Conquista x EMBRAPA 48). Pela análise de Qui-quadrado da avaliação fenotípica, confirmou-se à segregação esperada (3:1) de um gene dominante condicionando a resistência. Os marcadores polimórficos também segregaram conforme o esperado (1:2:1) já que possuem natureza codominante. Para as populações 1 e 2, os melhores resultados foram obtidos com os marcadores Sat_366 e Sat_393, respectivamente, localizando-se a 9,41 e 12,45 cM de distância do gene, sendo considerados promissores na seleção assistida para resistência ao oidio em soja. / Powdery mildew in soybeans, it is a disease present in virtually all producing countries. The molecular markers microsatellites or SSR (Simple Sequence Repeat) have been widely used in the assisted selection of soybean genotypes. The objective of this study was to obtain microsatellites markers near the gene for resistance to powdery mildew in soybeans. The study was conducted in two populations F2, from crosses between contrasting parents about the resistance to powdery mildew. For the study, were selected microsatellites markers at a distance of 42 cM around the gene Rmd (resistance to powdery mildew). It was used the method of BSA (Bulked Segregant Analysis) in the evaluation of markers, for comparison with the phenotypic analysis of populations. In the analysis were used in ten initiators SSRs for the two populations, and identified four polymorphic markers for the crossing 1 (MGBR95-20937 x-IAC Foscarin 31) and three for the crossing 2 (EMBRAPA MGBR 46/Conquista x 48). For the analysis of chi-square of the phenotypic evaluation, it is confirmed the segregation expected (3:1) of a dominant gene conditioning the resistance. The polymorphic markers also segregation as expected (1:2:1) that have already codominante nature. For the populations 1 and 2, the best results were obtained with the markers Sat_366 and Sat_393, respectively, finding itself to 9.41 and 12.45 cM distance of the gene and are considered promising in assisted selection for resistance to soybean in powdery mildew.

Orientador: Lauro Tatsuo Kubota / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-10T12:02:32Z (GMT). No. of bitstreams: 1 Mendes_RenataKelly_D.pdf: 1152307 bytes, checksum: c6e7b97417285a7bb4d70d28ba880353 (MD5) Previous issue date: 2006 / Resumo: Neste trabalho foram investigados diferentes métodos de imobilização da enzima HRP empregando como matrizes as monocamadas auto-organizadas formadas sobre eletrodos de ouro, bem como a avaliação da influência do processo de imobilização do elemento biológico no desempenho analítico do biossensor. Para isso. as monocamadas utilizadas foram formadas por meio de tióis com diferentes estruturas, tamanho de suas cadeias carbônicas e grupos terminais. Foi possível constatar que o tamanho da cadeia carbônica de um tioI influencia especialmente no empacotamento da monocamada e, conseqüentemente, na eficácia da imobilização das biomoléculas. Pelos estudos realizados visando a caracterização das SAM sobre a superfície eletródica foi possível verificar que os tióis que possuem em sua cadeia um número menor de carbonos (< 9) tendem a formar monocamadas com uma quantidade considerável de defeitos na superfície do ouro, o que leva a um recobrimento mais baixo. No entanto, os tióis que contém um número mais elevado de carbonos na cadeia apresentam um grau de recobrimento mais elevado e, no entanto, não são boas matrizes para biossensores eletroquímicos, pois podem passivar a superfície, diminuindo a transferência de elétrons e, como conseqüência, a sensibilidade do eletrodo. Quanto a imobilização da enzima nos eletrodos de ouro, verificou-se, por diferentes técnicas, que as monocamadas que possuem grupo terminal -NH2 foram aquelas que proporcionaram os melhores resultados, provavelmente devido ao uso do glutaraldeído como ligante no processo de imobilização. Ao analisar adicionalmente o desempenho do biossensor para a determinação de peróxido de hidrogênio, verificou-se que a SAM formada pela cisteamina é a mais adequada para a imobilização da HRP, por propiciar tanto uma melhor eficácia na adsorção enzima quanto uma sensibilidade mais elevada para H2O2 / Abstract: In this work different immobilization procedures of HRP were investigated using as support mIatrices the self-assembled monolayers formed on gold electrodes, as well as the evaluation of the influence of these immobilization processes in the biosensor performance. For this, the used monolayers were prepared by thiols with different structures, carbon chains size and terminal groups. It was possible to have evidence that the thiol carbon chain size influences especially in the coverage monolayer and, consequently, in the efficiency of the biomolecule immobilization. From the studies carried out for the SAM characterization on the electrode surface it was possible to verify that thiols with smaller chain (n<9) trends to form monolayers with a considerable amount of defects on gold surface, that it leads to a lower coverage. However, the thiols with a higher carbon chain present a higher coverage degree, are not being good matrices for electrochemical biosensors, because it can passive the surface, making difficult the electron transfer and, consequently, the electrode sensitivity. In relation to the enzyme immobilization on gold electrodes it was verified, for different techniques, that monolayers that possess -NH2 terminal group provided the best results, probably due to the use of glutharaldeyde as ligant at the immobilization process. Analyzing the biosensor performance for the hydrogen peroxide determination was verified that SAM formed by cysteamine is more adequate for HRP immobilization, because provide the better efficiency in the enzyme immobilization associated to high sensitivity for H2O2 / Doutorado / Quimica Analitica / Doutor em Ciências

Magíster en Ciencias, Mención Física / En esta tesis se estudian los procesos de oxidación de películas delgadas de cobre desnudas y recubiertas con 1-dodecanotiol. Mediante microscopía de efecto túnel y microscopía de fuerza atómica se estudió la morfología de estos sistemas, y con espectroscopía de fotoelectrones inducida por rayos X y método de cuatro contactos se estudió la evolución de la oxidación superficial. Se observó que el método de fase líquida para la preparación de muestras, en el rango entre un minuto y un día, genera una monocapa auto-ensamblada (SAM) de 1-dodecanotiol bien empaquetada sobre la superficie. La SAM molecular es un buen protector de la corrosión porque inhibe la oxidación de la superficie, sin embargo, al cabo de varias semanas también sufre un proceso de oxidación que deteriora su calidad protectora. Además se observó que las características morfológicas de las muestras sí afectan la oxidación superficial. Concluyendo, para obtener mejor protección a la oxidación superficial, las películas delgadas de cobre deben ser de amplios granos con extensas terrazas, para así favorecer el empaquetamiento y buen ordenamiento de la SAM molecular.

Magister Artium (Child and Family Studies) - MA(CFS) / Introduction: Malnutrition is the immediate result of inadequate dietary intake, the presence of disease or the interaction between these two factors. It is a complicated problem, an outcome of several etiologies. SAM is one of the leading causes of morbidity and mortality among children under the age of five in developing countries. Although studies in Botswana show some improvement in child malnutrition since the 1980s, severe acute malnutrition still remains a cause for concern in many parts of the country. There is little information on undernourishment situation of children under the age of five years in the urban areas of the country. Aim: The purpose of this study was to determine the risk factors to severe acute malnutrition among children under the age of five years in Francistown, Botswana. The UNICEF conceptual framework was used as a guide in assessing and analysing the causes of the nutrition problem in children and assisted in the identification of appropriate solutions. Methods: The study was conducted on cases who had been admitted and referred at any time between March and July 2015. A quantitative research methodology was used to conduct the study. A case-control study design was utilised. Random selection of cases and controls was done on a ratio of 1:2 case per control. Cases included children under the age of five years admitted to Nyangabgwe Referral Hospital and those referred to the Nutritional Rehabilitation Centre within the hospital in Francistown-Botswana with a diagnosis of severe acute malnutrition. Controls were children of the same age, gender and attending the same Child welfare clinic as the case and with good nutritional status. Data was collected through face-to-face standardised interviews with care-givers. Results: Data collection was done using a combination of a review of records (child welfare clinic registers, and child welfare clinic cards) and structured questionnaires. 52 cases and 104 controls were selected with the primary or secondary care-giver as the respondent. (N=156). Data was collected using a self-developed structured questionnaire and the review of documents. Of all the cases 36.5% (n=19) were diagnosed with MAM, 46.2% (n=24) with SAM, 1.9% (n=1) with moderate PEM and 7.7% (n=4) each for PEM and Severe PEM. All the cases had presented with clinical signs and symptoms of severe acute malnutrition and/or the weight-for-height Z-score of ≤ -3 SD. Following placement of the data in regression models, the factors that were found to be significantly associated with child malnutrition were low birth weight (AOR = 0.437; 95% CI = 0.155-1.231) , exclusive breastfeeding (AOR = 2.741; 95% CI = 0.955-7.866), child illness (AOR = 0.383; 95% CI = 0.137-1.075), growth chart status (AOR =7.680; 95% CI = 1.631-36.157), level of care-giver’s education (AOR = 0.953; 95% CI = 0.277-3.280), breadwinner's work status (AOR = 1.579; 95% CI = 0.293-8.511), mother’s HIV status (AOR = 0.777; 95% CI = 0.279-2.165), alcohol consumption (AOR = 0.127; 95% CI = 0.044-0.369), household having more than one child under the age of five (AOR = 0.244; 95% CI = 0.087-0.682), household food availability (AOR = 0.823; 95% CI = 0.058-11.712), living in a brick type of house (AOR = 13.649; 95% CI = 3.736-49.858), owning a tap (AOR = 1.269; 95% CI = 0.277-5.809) and refuse removed by the relevant authority (AOR= 2.095; 95% CI = 0.353-12.445) were all statistically significantly associated with severe acute malnutrition (p < 0.05). Therefore, all these variables were included in the binary stepwise regression where living in a mud house type was the most significant factor and not being breastfed for at least three months was the least significant. Conclusion: The findings of this study suggested that immediate determinants to SAM were; child born with a low birth weight, appetite and child illness. Underlying contributing factors were; the child not exclusively breastfed for at least three months, growth chart not up to date, care-givers education level, employment status, alcohol consumption, household food availability, type of housing, owning a tap and number of children under the age of five year. Therefore, increasing household food security and strengthening educational interventions for women could contribute to a reduction in the prevalence of SAM in Francistown, Botswana.

Re-powering solar PV plants is an upcoming discussion on the global stage. Although the respective component warranties indicate the time to change the system machinery, the methodology and justification for carrying this out are two aspects that need further study. The rooftop solar PV system on top of Dalarna University was re-positioned in 2014. Prior to installing the system in its new position, the system arrays were reconfigured and new inverters were installed. This thesis aimed to compare and analyze two sections of the solar power plant to understand which amongst them performs better. Graphs depicting energy, current, voltage and other parameters were formulated to ascertain the efficacy of the array configurations for this Nordic latitude. Thereafter, PVsyst and SAM were used to compare the simulated results with the actual output from the system. It was found that the measured energy output from one section of the solar power plant was higher than that of the other during 2014. On an annual basis, this difference was 21.5 kWh or 2%. On closer inspection, this contrast was attributed to a difference in yield early in the morning. Further, PVsyst simulated the annual energy with a deviation of less than 1% than what was measured, whereas SAM measured a deviation in energy measurement of 2.5% higher than the actual measured energy. These values were obtained using the detailed design options for both softwares. A point to keep in mind is that prior experience of working with both these softwares is recommended prior to carrying out the simulations on these softwares. An underlying point to note in this study is its limitations. This study is valid in the northern latitudes, such as the Nordic climates, since other regions would not have such low (sub-zero) temperatures to account for while sizing the inverter. In regions of high irradiance, a system re-powered in a way such as the system in this case would have higher clipping losses. Relevant previous studies and related topics have been visited, summarized and cited.

The research in this thesis aims to develop new mechanistic knowledge for coating processes at 2024-Al alloy surfaces, ultimately to aid the design of new protective coatings. Coatings formed by phosphating, chromating, and permanganating were characterized especially by scanning Auger microscopy (SAM), X-ray photoelectron spectroscopy, and scanning electron microscopy . The objective was to learn about growth (nm level) as a function of time for different coating baths, as well as a function of lateral position across the different surface microstructural regions, specifically on the μm-sized Al-Cu-Mg and Al-Cu-Fe-Mn particles which are embedded in the alloy matrix . The research characterizes coating thickness, composition, and morphology. The thesis emphasizes learning about the effect of different additives in zinc phosphating baths . It was found that the Ni²⁺ additive has two main roles : first, the rate of increase in local solution pH is limited by the slower kinetics of reactions involving Ni²⁺ compared to Zn²⁺, leading to thinner zinc phosphate (ZPO) coatings when Ni²⁺ is present. Second, most Ni²⁺ deposition occurs during the later stages of the coating process in the form of nickel phosphate and a Ni-Al oxide in the coating pores on the alloy surface, increasing the corrosion resistance. Aluminum fluoride precipitates first during the initial stages of the coating process, followed by aluminum phosphate, zinc oxide, and finally ZPO. When Ni²⁺ is present in the coating solution at 2000 ppm, ZnO predominates in the coating above the A-Cu-Fe-Mn particle while ZPO dominates on the rest of the surface. The Mn²⁺ additive gives a more even coating distribution (compared with Ni²⁺) across the whole surface. The Mn²⁺ -containing ZPO coating is similar to the chromate coating in terms of evenness, while there is more coating deposition at the second-phase particles for permanganate coatings. The oxides on the Al-Cu-Fe-Mn and matrix regions are similar before coating, thereby confirming that a variety of observed differences in ZPO coating characteristics at these regions arise from the different electrochemical characteristics of the underlying metals. Upon exposure to a corrosive solution, the ZPO coating provides more protection to the second-phase particles compared to the matrix. / Science, Faculty of / Chemistry, Department of / Graduate

Geology, opaque mineralogy, and alteration assemblages of the Sam Goosly copper-silver-antimony deposit are described in detail and a model for ore genesis is proposed. The deposit occurs in an inlier of Cretaceous sedimentary, pyro-clastic, and volcanic rocks. This inlier is intruded by a quartz monzonite stock in the western part of the property and by a gabbro-monzonite complex in the eastern half. Flat lying to shallow dipping Tertiary andesitic to basaltic flows uncomfortably overlie Cretaceous rocks around the flanks of the inlier. Based on careful examination of over 4,875 m of drill core and on limited surface mapping, four stratigraphic subdivisions striking about 015 degrees and dipping about 45 degrees west have been identified. The Clastic Division, composed of a lower polymictic conglomerate and an upper chert pebble conglomerate, is lowermost and is thought to be correlative with the Skeena Group. Sedimentary rocks are overlain by the Pyroclastic Division, a heterogeneous sequence of tuff, breccia, and reworked pyroclastic debris. Tuff, sandstone, and conglomerate of the Sedimentary-Volcanic Division have well defined bedding and overlie pyroclastic rocks. The uppermost unit composed of andesitic and dacitic flows, is the Volcanic Flow Division. Copper-silver-antimony ores at Sam Goosly are contained in the Main Zone and Southern Tail deposits and are associated with tourmaline, andalusite, scorzalite, and corundum (only in the Main Zone). They are epigenetic and cross-cutting relationships are visible both in hand specimen and throughout the deposit as a whole. The ores occur within the Pyroclastic Division and although they are controlled mainly by structure, crude strati graphic controls are also apparent. Other mineralized areas at Sam Goosly are a zone of porphyry copper-molybdenum mineralization in and adjacent to the quartz monzonite stock and a zone of tourmaline breccia. Similarities in mineralogy, textures, and paragenesis among all four mineralized areas suggest that they are genetically related. Potassium-argon dating of hydrothermal alteration indicates that mineralization occurred almost simultaneously with, the emplacement of the quartz monzonite stock. It is suggested here that copper-silver-antimony ores are related to the porphyry system and were deposited in a subvolcanic environment peripheral to porphyry mineralization. Early stages of mineralization took place between 400° C and 491° C; sulfides continued to form as the system cooled below 300° C. During subsequent thermal metamorphism of the Main Zone deposit adjacent to the gabbro-monzonite complex, pyrrhotite and sillimamite formed in an aureole about 90 m wide. Temperatures during metamorphism are thought to be above 750°C and pressures to be less than 350 bar (about 1 km depth). / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Unknown

This thesis is a critical history about Cranbrook BC, the town where I grew up. It explores a historical origin story that historians have called the ‘Kootenai Uprising,’ as well as the annual regional holiday that commemorates that event - Sam Steele Days. By unpacking the symbols utilized in remembering history, applying new historical evidence towards the long accepted narrative and collaborating with Ktunaxa Nation, this thesis attempts to set the historical record straight, include Ktunaxa perspectives in the regional historical narrative and critically examine the practice of mythology in settler society as a way to both remember and forget the past. / Graduate / 2021-08-28

We investigated the transfer of three antioxidants - melatonin, S-adenosyl methionine (SAM) and various forms of vitamin E - across the term, normal human placenta. The transport technique involved the single, isolated placental cotyledon system in vitro. Melatonin crossed the placenta rapidly, equally to the freely diffusible marker, antipyrine. There was no biotransformation of the agent. SAM was transferred slowly, similarly to passively transported L-glucose as a marker. There was a breakdown of SAM to at least one other derivative; the process appeared to be nonenzymatic. Vitamin E was transferred slowly, at a rate only 10% of L-glucose. The natural RRR (nonracemic) form of vitamin E was transported best. Free vitamin, rather than the acetate seems to be transferred best, a finding that will require further study.

Electrochemical biosensors have been used to detect biomarkers sensitively at low limits of detection. The organic electrochemical transistor (OECT) is a special class of electrochemical biosensors characteristically known for its intrinsic amplification abilities. Nevertheless, if the biosensor is to be used with real clinical samples a strategy aiming to increase the specificity of the device other than the dependance on the respective biorecognition unit is necessary to minimize, if not eliminate, interference from foulants in complex biological media. In this work we test the antifouling performance of several Poly(ethylene glycol) based SAMs using Electrochemical impedance spectroscopy (EIS). We also evaluate the overall performance of the device and its ability to detect total α-synuclein, its aggregate and phosphorylated forms spiked in heat-inactivated human serum. Limits of detection in the fM and aM ranges were achieved.