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Obtenção de blenda biodegradável PLA: amido para a incorporação do micronutriente manganês
(Universidade Federal de São Carlos, 2016-09-30) Malafatti, João Otávio Donizette; Paris, Elaine Cristina; https://lattes.cnpq.br/8475640212486290; https://lattes.cnpq.br/9880071190362996
The incorporation of particulate fertilizers in polymeric fibers aims to release these active principles from a substrate with a high surface area and biodegradable and biocompatible properties. It also seeks to provide the release thereof, and minimize the effects of leaching, increasing the efficiency of absorption by the roots in direct soil application. Thus, the present study was to interest obtaining a composite biodegradable matrix of acid poly -L- lactic (PLA):starch in the form of fibers, impregnating particulate solids that can act as sources of manganese ions. It is also aimed to assess any improvement in the release of the Mn2+ ions in an aqueous medium by means of variations in the processing of biodegradable blends. PLA fibers were obtained employing the electrospinning method, various solvent systems primarily been studied for obtaining a polymer solution, in order to obtain the best morphological characteristics for the support, such as control of the fiber diameter and porosity. Then there was the addition of different concentrations of starch in order to find the best embodiment of this condition to the fibers. Finally, we performed the inclusion of MnO, MnO2, MnCO3 and MnSO4, to act as sources of manganese ions, in order to observe possible and different interactions of these with the polymer matrix. In the release test, the same concentration of manganese ions 12.5% (w/v) was added experimentally to a medium extractant citric acid 2 % (w/ w) at 25 ° C in a range of 6 days for all the aforementioned precursors. It was observed that the presence of starch in the PLA fiber increased water vapor permeability (WVP) which promotes the degradation of the blend. The incorporation of salts and oxides in the blends PLA:starch used by the process resulted in different effects of the merger, agglomeration and dispersion in the composite due to its grain size and dispersive characteristics in the solvents used. The behavior of salts and manganese oxides embedded in composite promoted the rapid and direct release of assets. The composites PLA:starch is a polymeric support with high surface area which minimizes the effects of leaching allowing direct release of different precursors ion Mn2 + as fertilizer sources.
Abordagens sintéticas para a funcionalização de novas porfirinas
(Universidade Federal de São Carlos, 2016-09-30) Barona Castaño, Juan Camilo; Oliveira, Kleber Thiago de ; https://lattes.cnpq.br/3759761373942891; https://lattes.cnpq.br/1969014633859806
Herein, we optimized some conditions in the synthesis of a β-octasubstitued porphyrin with electron withdrawing groups (1). This system was used to study the bromination of the meso position aiming at subsequent cross-coupling reactions and meso-functionalization of these porphyrin systems (Scheme 3). The main goal was to obtain porphyrin derivatives with modulations in the UV-visible spectra with potential application as photosensitizers for photodynamic therapy treatments (PDT). We found better conditions for the preparation of the porphyrin 1 changing the formaldehyde precursor from trioxane to dimethoxymethane, and reducing the time of second step in the reaction (oxidation of the porphyrinogen). The yield was increased to 13%. After the optimization of 1, different bromination methodologies were tested in order to obtain the meso-bromoporphyrins 2 or 3; but unsuccessfully. In this perspective, we also proposed the synthesis of β-fused porphyrins with imide moieties (Scheme 4), being the functionalized pyrrole 8 the starting material. Porphyrins 9 and 11 might be alternatives for the preparation of new substituted derivatives via cross-coupling reactions, leading to compounds with different photophysical properties. The synthesis of porphyrin 9 was not succeeded by the approaches adopted here, showing only complex mixtures or total degradation of 8. Furthermore, experiments for the formation of dipyrrolmethane 10 were made without any success, precluding the construction of the porphyrin 11. Certain intermediates of interest could be isolated with relative success, and future explorations will be considered.
Filogenia molecular e filogeografia do gênero Salminus (Characiformes)
(Universidade Federal de São Carlos, 2016-09-30) Silva, Carolina de Barros Machado da; Galetti Júnior, Pedro Manoel; https://lattes.cnpq.br/7398754661670478; https://lattes.cnpq.br/5400931880079477
Salminus is a genus comprised of four Neotropical medium- and large-sized fishes species, top predators, with both recreational and commercial importance. The paucity of information on taxonomy, phylogeny and phylogeography make appropriate conservation policies difficult for the genus, which is in a significant population decline. For this reason, our goal was, by using mitochondrial (COI, Cytb and D-loop) and nuclear (RAG2 and S7 intron) molecular makers, to elucidate taxonomic uncertainties, identify cryptic diversity, investigate the phylogenetic relationship among the species and infer the historical processes that shaped the current Salminus distribution. To assist in taxonomic issues, we employed the traditional DNA barcoding and GMYC COI-based analyses in 110 specimens, representing the four valid species. In both methodologies, eight MOTUs (molecular operational taxonomic units) were identified. Only two species, Salminus affinis and Salminus franciscanus, represented a MOTU each. The species Salminus brasiliensis and Salminus hilarii were represented by two and four MOTU, respectively. These MOTUs are distributed in distinct hydrographic basins where morphological polymorphisms had already been described. The average intraspecific distances greater than the optimal threshold of 1.1% (S. brasiliensis – 3.6%, e S. hilarii – 5%), reinforce the idea of more taxonomic units in Salminus. The multiloci analysis recovered interesting information about the cryptic diversity: the paraphyletic mitochondrial lineages of S. brasiliensis, one from Upper Paraná river and another composed of specimens from the other regions of the Platina basin, formed a unique monophyletic group. For S. hilarii, despite the four MOTUs observed, only three of them were recovered. Therefore, based on multiloci analysis and phylogenetic species concept, we proposed a new taxonomic scenario for Salminus. The genus is now composed of six species: S. affinis, S. franciscanus, S. brasiliensis, S. hilarii, Salminus sp. Amazonas and Salminus sp. Araguaia. The phylogeny reconstruction refuted hypotheses previously proposed. S. affinis, the only trans-Andean species, was the sister species of the other Salminus, which formed two main groups: Northwest group, composed of S. sp. Amazonas and S. sp. Araguaia, and Southeast group, formed by S. brasiliensis, S. franciscanus and S. hilarii. The divergence processes among Salminus began in Later Miocene and it is associated with vicariance and geodispersion events that shaped the hydrological landscape in the past 12 million years. For the first time, it was used a model-based approach in order to test alternative biogeographic scenarios and to distinguish phylogeography signatures among the events responsible for Neotropical fishes’ diversification. We evidenced that the distinct vicariance and geodispersion signatures could be detected in our biological model. A clear description of these species brings in a valuable information for conservation, because, now, six biological units need to be protected. As these species are located in distinct hydrographic basins, each basin becomes one important biogeographic unit to maintain the evolutionary and ecological processes that sustain the species permanence and diversity.
Zircônia CO-dopada por compensação de cargas nos sistemas (ZrO2)1-(x+y)(InO1,5)x(MOz)y com MOz = TaO2,5, NbO2,5, MoO3 ou WO3, como revestimento para barreira térmica
(Universidade Federal de São Carlos, 2016-09-30) Piva, Roger Honorato; Morelli, Márcio Raymundo; https://lattes.cnpq.br/0172837599844991; https://lattes.cnpq.br/0515321727144523
InO1.5-stabilized zirconia (InSZ) is a potential hot corrosion resistant thermal barrier coating (TBC). However, the thermal instability prevents real applications of InSZ-based TBC. This thesis investigates the hypothesis of co-doping using the charge compensation to improve the phase stability of InSZ. Four co-doping systems were synthesized by coprecipitation and studied: (ZrO2)1-(x+y)(InO1.5)x(MOz)y with MOz = TaO2.5, NbO2.5, MoO3, or WO3. After synthesis, 9 mol% of InO1.5 plus the charge-compensating oxides was sufficient to stabilize the tetragonal phase. Specific surface area up to 106.1 m2.g-1 and crystallite size ~11 nm were achieved using ethanol washing followed by azeotropic distillation as dehydration technique in the precipitates. In these powders, initial thermal stability analysis indicated instability of the tetragonal phase, with extension of the t→m transformation less detrimental in the InMoSZ system. Further increase in the concentration of InO1.5:MoO3 results in monophasic samples with retention of cubic phase in the InMoSZ. Cubic InMoSZ exhibited hardness and thermal expansion coefficient of 13.5% and 9% higher than those of InSZ, respectively. However, thermal treatments at T ≥ 1200 °C showed that the InMoSZ is also passive to destabilization of the high temperature cubic polymorph. Although the cubic InMoSZ was the most promising system found in this thesis, the stability results do not support its application as TBC for temperatures ≥ 1000 ºC. A deep evaluation of the phase transformations between 1000 to 1200 °C indicated that the instability of the proposed systems is due to a progressive c→t→m destabilization of the polymorphs. This c→t→m transformation is directly associated with the reduction of the InO1.5 stabilizer in solid solution by volatilization as In2O during heat treatment. At temperatures ≤ 800 ºC, the c→t phase transformation do not occurs, then, InSZ-based TBC is stable in these conditions.
Uso da terra e avaliação da naturalidade para o planejamento e manejo ambiental de bacias hidrográficas (Sudeste do Brasil)
(Universidade Federal de São Carlos, 2016-09-30) Costa, Rômulo Theodoro; Fushita, Ângela Terumi; https://lattes.cnpq.br/1078644223231926; Santos, José Eduardo dos; https://lattes.cnpq.br/8533387365058570; https://lattes.cnpq.br/4398421359856351
Ecosystems managed manifest vulnerability according to decline of ecological resilience and depletion or loss of the main ecosystem service flows. Driving forces acting in landscape result in changes, which require regional management actions and / or local, in conjunction with other external factors. To operationalize these concepts in landscape management, this study approached the dynamics of the intensity changes in land use and conservation conditions of biodiversity scenarios, between 2004 and 2014, for the Jacaré-Guaçu and Jacaré-Pepira watershed rivers. The same analyzes were applied on floodplains formed at the Jacaré-Guaçu and Jacaré-Pepira headwaters in 2004, 2014 and 2015. Conditions of sustainability, involving environmental aspects from the land use and cover dynamic and sustainability indicators were assessed in these areas. Land use and cover dynamics maps were produced based on visual interpretation of Landsat images. Biodiversity conservation scenarios were designed based on Urbanity Index, which estimates the naturalness landscape conditions. The results showed a predominantly anthropogenic scenario, induced by expansion of the agricultural anthropogenic and non-agricultural anthropogenic land uses, and trough conversion of other land use types in sugarcane and forestry. The historical process of land use occupation for agricultural production remains the main driving force of landscape changes, which currently occupies more than 70% of the watersheds area. The Jacaré-Guaçu watershed river presented a critical scenery due to naturalness areas losses and critical naturalness areas increase. The biodiversity conservation scenery showed a reduction area and spatial displacement between 2004 and 2014, resulting from loss and fragmentation of natural capital in the watersheds. Despite the increase in natural vegetation areas, the watershed are far from a sustainable condition, according to loss of carrying capacity and the ecosystem services provision. There was no changes evidenced in land use and cover in floodplains, however, the localization of floodplains showed high vulnerability due to agricultural and urban areas, which indicates evidence of sustainability losses evidences.
Trajetórias e caminhos : uma cartografia dos bebês
(Universidade Federal de São Carlos, 2016-09-30) Oliveira, Julia Yoko Tachikawa de; Abramowicz, Anete; https://lattes.cnpq.br/2502752385941894; https://lattes.cnpq.br/5130233558284874
This research aimed to trace the movements of the babies through the cartography, considering them protagonists of the traces. Aiming to promote a discussion about the research methodology for studies of babies in their specificities on the spaces they occupy, the work mapped the babies movements and actions daily in a public space, in a collective context of experiences, in an institution of early child education and care. The methodology of research was qualitative approach in the ethnographic type with participant observation, capture of images and records, this documentation and diaries was transcribed in maps accompanied by subtitles and descriptions of scenes. The theoretical framework was based on the Sociology of Childhood, with William Corsaro, with the model of the global web and a cultural routines, and in Fernand Deligny, for a cartography, whose practices of maps were revealed as a form of transcription of the "voices", movements, affections, encounters and not the explanation of the origin or nature of movements or other forms of interpretations about behaviors and standardized actions. The research uses a language for the possibility of indicate some paths and tracks to enlarge our understanding of the " babies world " and looked for knowledge in how works can be as starting points babies participation as sources and informants, to be constitute in a research with babies, not just about babies.
O problema pseudoviscoso e a equação de BBM-Burgers estocásticos
(Universidade Federal de São Carlos, 2016-09-30) Carneiro, Evaneide Alves; Kondo, Cezar Issao; https://lattes.cnpq.br/0900348462714778; https://lattes.cnpq.br/7748150619501176
This work is divided in two parts: In the first part, we study the convergence of a sequence of approximating solutions to a solution of the stochastic conservation law, in the additive and multiplicative case. In the second part, we obtain existence, uniqueness and regularity results to a solution of the Benjamin-Bona-Mahony-Burgers (BBMB) stochastic equation.