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Estudo da variação do perfil químico de Citrus sinensis sobre Citrus limonia após a inoculação da bactéria Xylella fastidiosa
(Universidade Federal de São Carlos, 2011-06-22) Soares, Márcio Santos; Silva, Maria Fátima das Graças Fernandes da; https://lattes.cnpq.br/0457632122660653; https://lattes.cnpq.br/7277672046313544
The present work describes the study of variation in the chemical profile of citrus after inoculation of Xylella fastidiosa, in charge of the Citrus Variegated Chlorosis is one of the most serious diseases that cause damage in Brazilian citrus. The bacterium X. fastidiosa was inoculated in Citrus sinensis grafted on C. limonia and was evaluated using chemometric tools and development of analytical methods such as HPLC-DAD, LC-MS/MS, LC-UV-SPE-NMR and HRMAS quantitative variation of some secondary metabolites such as coumarins and flavonoids identified both in grafts and in the matrix C. sinensis and C. limonia. The chemometric methods PCA and HCA applied to the data obtained in studies by HPLC-DAD and HR-MAS allowed to discriminate plants contaminated with the bacteria of the species healthy, as well as the respective individuals. By analyzing the change in the chemical profile of citrus studied by HPLC-UV-SPE-NMR it was possible to detect the presence of a new class of secondary metabolites derived from p-hidroxy-cinnamic acid containing oxidized dihydropyran and dihydrofuran rings. Similarly, when analyzing the compounds of medium polarity by LC-MS/MS technique was identified, until now, in the roots and leaves several coumarins not cited in the literature for any of the species that constitute the graft, as dihydrosuberenol, 2 ', 3'-dihydrosuberosin, citrubutin the limonoid diosfenol limonin and flavonoid 3-hydroxy-3', 4 ',5,7,8- pentamethoxyflavone. Finally, was observed that coumarin bergapten is present in reasonable quantities only in the leaves of Rangpur lime, which is tolerant to X. fastidiosa, and when the graft presents with symptoms of citrus variegated chlorosis is a small production of this in their leaves, indicating that this is a phytoanticipin.
Desenvolvimento de união de multimateriais através de rebitagem por injeção (Injection Clinching Joining)
(Universidade Federal de São Carlos, 2011-06-22) Abibe, André Bastos; Hage Júnior, Elias; https://lattes.cnpq.br/1240692926327687; https://lattes.cnpq.br/4861834283924996
Multimaterial structures are currently a technologically attractive field of research. The growing use of polymer composites replacing metals in structures aiming for weight and emission reduction is part of the motivation of this study. The currently used techniques adhesive bonding and mechanical fastening are limited in certain aspects, opening a path for innovation in this area. Joining of polymers and metals via Injection Clinching Joining (ICJ) is an innovative technique based in injection molding, adhesive bonding and staking. This work studies this technology in its theoretical aspects and applies it to a preliminary study with commercial materials: 30% short glass fiber reinforced polyamide 6,6 (PA66/FG30%); and aluminum alloy AA2024-T351. A design of experiment of one factor at a time analyzed effects of the process parameters on macro- and microstructure, local and global mechanical properties, and thermal properties. It was possible to create joints in which the polymer completely filled cavities in the metallic hole, but the reproducibility was not good, for most joints had only partial filling of the cavities, factor which improves the mechanical performance of the joint. The lap shear testing of overlapped joints determined the global mechanical strength of the joint, which ranged from 20,90 MPa to 51,48 MPa (35,9% to 88,5% of the ultimate tensile strength of PA66/FG30%), and the best performances are attributed to a large contact volume of polymeric material with the chamfer on top of the stud, and effective cavity filling. Two types of fracture were observed, a ductile and gradual (rivet pull-out), and a fragile and catastrophic (net-tension). The thermal properties of the polymer after joining were not significantly changed compared to the base material. This scientific and technological research featured ICJ as a viable process for joining of multimaterial structures, achieving good mechanical performance without significantly changing the properties of the base materials.
Estudo morfológico dos estádios ninfais das fêmeas de Ceroplastinae Atkinson (Hemiptera: Coccoidea: Coccidae)
(Universidade Federal de São Carlos, 2011-06-22) Rosa, Keila de Cassia Coelho; Silva, Carlos Roberto Sousa e; https://lattes.cnpq.br/4890369735136839; https://lattes.cnpq.br/6984640335958321
The immature females of twelve species of Ceroplastinae (wax scale insects) were described and compared, macro and microscopically, with the purpose of contributing to the understanding the groups of the species of this subfamily, whose generic status is controversial. The morphology of the immatures, although little studied and not yet used in the phylogenetic studies of this subfamily, was very important for the grouping of the studied species. Nymphs of the first and second instars varied widely in relation to the wax test and the stigmatic setae, separating the species studied in three main groups: I) C. cirripediformis Comstock, 1881, C. floridensis Comstock, 1881, C. formicarius Hempel, 1900, C. grandis Hempel, 1900, C. mosquerai Ben-Dov, 1993 and C. rusci (Linnaeus, 1758), with dry wax filaments and with cylindrical or slightly conical and conical stigmatic setae with rounded apex in the first instar and setae totally conical in the second instar; II) C. formosus Hempel, 1900, C. janeirensis (Gray, 1828) and C. lucidus Hempel, 1900 with a shell of wax glassy and absence of lateral expansions or dry filaments and with stigmatic setae cylindrical with rounded apex and wider than the base, in the two first instars, and III) C. diospyros Hempel, 1928, C. flosculoides Matile-Ferrero, 1993 and C. iheringi Cockerell, 1895 with intermediate characteristics in waxy covering and setae with pentagonal or irregular shapes. The pattern of wax test observed for the group I, previously mentioned for other authors, was the most frequent among the studied species and better distributed in the world, being probably the most common pattern in Ceroplastinae. The patterns of wax cover observed for Groups II and III are here described for the first time for the immature females of Ceroplastinae. The group II is probably restricted to the Neotropical region, and the group III, including Neotropical species, probably has representative species in the Afrotropical region.