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Estudos citogenéticos em espécies das tribos Hypostomini e Ancistrini (Loricariidae, Hypostominae)
(Universidade Federal de São Carlos, 2011-09-02) Rubert, Marceléia; Moreira Filho, Orlando; https://lattes.cnpq.br/3927076022470557; https://lattes.cnpq.br/5065670903691241
Conventional and molecular cytogenetic analysis were performed on 15 species of the subfamily Hypostominae, comprising 12 species of the Hypostomini tribe, genus Hypostomus, and three of the Ancistrini tribe, genera Ancistrus and Hemiancistrus. The chromosome number of 2n=52 was observed for Ancistrus multispinis (14m+14sm+24st-a), A. brevipinnis (14m+14sm+24st-a) and Hemiancistrus punctulatus (14m+26sm+12st-a). The nucleolar organizer regions (Ag-NORs) and 18S rDNA sites are simple and terminal for species, A. brevipinnis, A. multispinis and H. punctulatus. In these species, it can be seen that the NORs are also CMA3+/DAPI-. As for the heterochromatin, H. punctulatus showed a small amount of this chromosome component, while A. multispinis and A. brevipinnis showed a larger amount, with large blocks on the long arm of some st-a pairs. In turn, the different species of Hypostomus showed a variation from 64 to 82 chromosomes, exhibiting differences in the karyotype formula between species. The NORs were multiple for most species analyzed, with different phenotypes observed in the number and position, which was also confirmed by FISH analysis, showing an interindividual and interspecific variability. In all species, the NORs were also CMA3+/DAPI _. The heterochromatin pattern distribution was different in each species, being another important chromosome marker. Cytogenetic, molecular, and morphometry analysis were performed in the species Hypostomus albopunctatus (Piracicaba river, SP) and H. heraldoi (Pirapitinga river, GO), including those morphologically similar samples present in the Mogi Guaçu river (SP). All individuals had 2n=74, whereas H. albopunctatus showed 10m+20sm+44st-a and H. heraldoi 8m+20sm+46st-a. These two karyotype formulae were found in the Mogi Guaçu river population. Distinct Ag-NOR phenotypes were observed among the three populations and confirmed by FISH. Regarding the heterochromatin pattern, H. albopunctatus presented terminal bands and an interstitial block. In H. heraldoi, the heterochromatin was found widely distributed in the terminal and interstitial regions of some st-a chromosomes. In these species, the NORs were also CMA3+/DAPI _. RAPD analysis and sequencing of the cytochrome oxidase subunit I (COI) gene were carried out in these two species, in the Mogi Guaçu population and in three more species, H. regani, H. margaritifer, and H. hermanni, obtaining the same dendrogram pattern. All species could be differentiated by their COI sequences, resulting in a total of 16 haplotypes. These analyses, combined with the morphometric data, showed that H. heraldoi and H. albopunctatus are two valid species and the specimens from the Mogi Guaçu river still retain some characteristics of H. albopunctatus, and were provisionally designated as Hypostomus aff. albopunctatus. Due to the large number of species currently included in the Hypostomus genus, along with both the intra and interspecific variability in morphology and color pattern, there are often problems in the taxonomy of this group, which can be assisted by cytogenetic data. This study provided new chromosomal data for Loricariidae, being a valuable cytotaxonomic tool for the Hypostomini tribe. The joint analysis of different characters, such as cytogenetic, molecular, and morphometric, allowed a more precise characterization of different populations of Hypostomus species, helping to clarify their validity as distinct evolutionary units.
A influência do fósforo na toxicidade de cobre e composição bioquímica de Chlorella vulgaris
(Universidade Federal de São Carlos, 2011-09-02) Souza, Imyra Maíra Martins de; Lombardi, Ana Teresa; https://lattes.cnpq.br/6737850858443813; https://lattes.cnpq.br/3930565568802402
Metal toxicity to microalgae is dependent on environmental conditions, evolutionary history of the microalgae, and previous exposure of the organism to the specific metal. Also, it is importantly influenced by the physiological condition of the algae in the moment of metal exposure. In this research we investigated several combinations of phosphorus (P) and copper (Cu) concentrations on the biochemical composition and Cu toxicity to Chlorella vulgaris. Due to its known toxicity, copper was considered in its free Cu2+ ions specie. Because microalgae physiology reflects the environmental conditions, but it also stores some of the inorganic nutrients, previous to Cu spike in the cultures, the algae were acclimated to each treatment s specific P concentration to be tested in combination with Cu. We considered cells were acclimated to a specific P concentration after its growth rate had been stabilized for at least four generations, always transferring the cells while in the beginning of the exponential growth phase. Biomass and physiological parameters analyzed were cell number (cell.mL-1), chlorophyll-a concentration, dry weight, lipid classes (Iatroscan TLC/FID), and total cellular proteins and carbohydrates at several combinations of P/Cu. The P concentrations tested were 5.0x10-5, 2.5x10-5, 5.0x10-6 and 1.0x10-6 mol.L-1 and the free Cu2+ ions concentrations ranged within 1x10-10 and 5x10-8 mol.L-1, and were determined through ion selective electrode (ISE). Our results showed that Cu toxicity to C. vulgaris increased at low P. Carbohydrate, protein and lipid productions were in general triggered at low P and high Cu, with some exceptions. TAG was the lipid class most affected by stressing situations. AMPL and PL were the lipid classes with the higher percent composition amog the classes; HC, WE and ST were present in minor amounts even under stressing situations.
Os Tupi Guarani de Barão de Antonina-SP: migração, território e identidade
(Universidade Federal de São Carlos, 2011-09-02) Almeida, Lígia Rodrigues de; Peggion, Edmundo Antonio; https://lattes.cnpq.br/9849805103860827; https://lattes.cnpq.br/9263580065240516
This thesis discusses how the Tupi Guarani who live in the district of Barão de Antonima, in the southwest of São Paulo state, conceive their territory in the context of demarcation of indigenous lands. Considering that the area they inhabit is currently undergoing under a process of demarcation. It also reflects how this indians rethink this context of territorial shifts, referring themselves as definers of their territories. And discussing the way how the myth treats about seeking for Lands free from evils. It (re) means locating the place where this land can be found. Not in the east, how the classical biography presents, but in all those places that the ancestors lived in, assuming different ways and contexts. The investigations carried out in the field articulated the bibliography review wish made me believe that if the demarcation of the lands didn't make sense to the Tupi Guarani groups, nowadays it became necessary. It's a way to guarantee inhabitable spaces where those groups would be able to reproduce their life style. This way it's not about the limitation of the movement or the fixation on a delimitated territory, but a way to guarantee that those groups continue to dislocate around a vast territory, circulating around villages and around demarcated indigenous lands.
Utilização dos mecanismos de apoio financeiro à inovação tecnológica por empresas de São Carlos - SP
(Universidade Federal de São Carlos, 2011-09-02) Bueno, Alexandre; Torkomian, Ana Lúcia Vitale; https://lattes.cnpq.br/6407503018881551