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Citogenética molecular comparativa do DNAr 18S e 5S em piranhas (Serrasalminae, Characidae) da Amazônia Central
(Universidade Federal de São Carlos, 2007-12-07) Nakayama, Celeste Mutuko; Bertollo, Luiz Antonio Carlos; https://lattes.cnpq.br/7301111160439489
Basic and molecular cytogenetic studies have been performed in 11 species of the subfamily Serrasalminae: Colossoma macropomum, Serrasalmus (S. altispinnis, S. elongatus, S. gouldingi, S. rhombeus, S. cf rhombeus, S. serrulatus and S. maculatus), Pygocentrus nattereri, Pristobrycon striolatus and Catoprion mento, collected along different sites in Central Amazon basin. The diploid number found was 2n=54 chromosomes in Colossoma macropomum, 2n=62 in C. mento and P. striolatus, 2n=60 for all species in the genus Serrasalmus and P. nattereri, except for S. cf. rhombeus, which presented 2n=58. Besides distinct diploid numbers, variable karyotypical formulae were also detected, even between species with the same chromosomal number, showing the occurrence of chromosomal rearrangements in the evolutionary process of this group, such as fusions and centric fisions and pericentric inversions. No sex chromosome heteromorphism was found in the analyzed species. The silver stained nucleolus organizer regions (Ag-NORs) were always telomeric and multiple, ranging from 4 to 12 marks according to each species. In most species, they were observed on short arms of subtelo-acrocentric chromosomes. However, in Colossoma macropomum the Ag-NORs were located at terminal position on long arms and, in Catoprion mento, they were present on short ams of submetacentric chromosomes and on long arms of subtelocentric and acrocentric chromosomes. The 18S rDNA sites were usually coincident with Ag-NORs, although they might occur in a higher number or in distinct chromosomes positions in relation to Ag-NORs. These discrepancies may be attributed to either methodological specificities or to difficulties in detecting some NOR sites, since they are commonly very small within Serrasalminae. The C-banded heterochromatin was observed at pericentromeric region of most chromosomes, being some regions more conspicuous than others, besides some telomeric bands in some chromosomal pairs. All Serrasalmus species presented a proximal heterochromatic block on the long arm of a medium-sized metacentric pair, which seems to be a marker for this genus regarding to its karyotype position (7th pair), once it may be present in other species, such as P. nattereri, but in a larger chromosome (3rd pair). The 5S rDNA sequences were always mapped in a single chromosomal pair. In Serrasalmus species, this pair corresponds to the metacentric pair 7 and in P. nattereri, P. striolatus and C. mento, it corresponds to the medium-sized metacentric pair 3. On its turn, the 5S rDNA sites in C. macropomum were located on short arms of a small metacentric, probably corresponding to the 12th pair. Considering the wide array of the present data, the species of the genera Serrasalmus, Pygocentrus, Pristobrycom and Catoprion, in spite of their specific differentiations, showed higher karyotypic similarity with the presence of metacentric, submetacentric, subtelocentric and acrocentric chromosomes, a preferential location of 18S rDNA sites at telomeric region on short arms of subteloacrocentric chromosomes, besides the number and location of 5S rDNA sites in karyotypes. On the other hand, C. macropomum shows quite divergent features, with 2n=54 meta-submetacentric chromosomes, with 18S rDNA sites at terminal region on long arms and interstitial 5S rDNA sites on short arms of chromosomes. Therefore, the location of C. macropomum far from the piranha clades, according to available phylogeny hypotheses for Serrasalminae, is corroborated by our cytogenetic data. Considering that C. macropomum would be a basal representative in the phylogeny of Serrasalminae, chromosomal rearrangements such as centric fissions, besides pericentric inversions, seem to play an important role in the karyotypic differentiation of this group, increasing the basal number of 2n=54 meta-submetacentric to 2n=58, 60 and 62, and giving rise to distinct chromosome forms in relation to those present in C. macropomum. Analogously, the NOR sites have also undergone numerical and positional changes in chromosomes along the karyotypical differentiation of Serrasalminae. As for the 5S rDNA sites, its location in a same position in morphologically similar chromosomes in all analyzed species of the genera Serrasalmus, Pygocentrus, Pristobrycom and Catoprion suggests that, once established this location from a distinctive ancestor condition, as that seen in C. macropomum, it has been remained conserved.
Reator enzimático de membrana para proteólise de soro de queijo, visando à produção de concentrado protéico com baixo teor de fenilalanina
(Universidade Federal de São Carlos, 2007-12-07) Padilla, Rebeca Yndira Cabrera; Giordano, Roberto de Campos; https://lattes.cnpq.br/0214528880301310
Enzymatic hydrolyzed proteins present some advantages over the pool of amino acids obtained after a chemical hydrolysis: lower osmolality (easier absorption by the organism) and better sensorial characteristics. The removal of phenylalanine (Phe) from these hydrolysates allows their use in the diet of phenylktonuria (PKU) patients. This Thesis studies the sequential hydrolysis of cheese whey proteins. This process aims at producing a protein hydrolysate with low contents of Phe, after two reaction stages: in the first one, concentrated cheese whey proteins are hydrolyzed by the endoprotease chymotrypsin, immobilized on agarose gel. The substrate of the second stage is the product of the first one. This reaction is the central focus of this Thesis, and consists in a hydrolysis using the exoprotease carboxipeptidase A (CPA), immobilized on the same matrix. Since the scope of this work was a process for obtaining a protein hydrolysate with low contents of Phe for phenylketonurics, another stage had to be incorporated: ultrafiltration, to separate the amino acids released by the action of CPA, mainly Phe (and other amino acids that inhibit the reaction). With this purpose, an enzymatic membrane reactor (EMR) is proposed. It should be noticed that, to the best of our knowledge, the reactor design presented here has not been published yet. The EMR had spherical agarose particles within the reaction space, retained by a stainless steel mesh (400 Tyler). Hence, the ultrafiltration membrane was in charge only of the separation of the amino acids in the hydrolysate, which was continuously recycled to the flask containing the immobilized enzyme. Assays to characterize the membranes were performed. These membranes were then used in the integrated process (reaction with immobilized enzyme coupled to the ultrafiltration), for different experimental conditions. The substrates where Prato and Minas Frescal cheese whey. Two set-ups of the ultrafiltration unit were tested: flat plate and hollow fiber, both with 1 kDa cut-off. The reactor volume/membrane area ratios were 7.5×10-2 cm and 76.9×10-2 cm, respectively. Finally, the performance of three systems was compared: EMR with flat plane and hollow fiber and a batch reactor, followed by diafiltration. The hollow fiber EMR showed the best performance (85% conversion, productivity of 275.2×10-7 ghidrolisado/mgPhe/UH-PHE/h and only 1% retention of Phe in the membrane, after assays of 10 h). The resulting product was appropriate for phenylketonurics, with high protein contents (53.4 g/L), mainly constituted by small peptides (≤ 5.8 kDa) and with 19.9 mgPhe/gProteína, within the admissible range for PKU
Construção da ação docente: aprendizagens de professoras leigas em classes multisseriadas na escola do campo
(Universidade Federal de São Carlos, 2007-12-07) Rocha, Solange Helena Ximenes; Mizukami, Maria da Graça Nicoletti; https://lattes.cnpq.br/2111834686921552
The investigation of different processes that involve the teaching formation has been object of studies in Brazil and abroad and point a to the necessity of that the teachers know and do its daily one. Its still considered important, that the studies fill existing gaps in different sectors of the magistery and contemplate the rural schools and far way from great centers as the rural schools and its teachers. This research argues the learning of teaching and formation of four teachers who had entered as lay people multisseries classrooms in the rural school and had as its professional development in multisseries classrooms. This work characterizes as being an description-analytical study of qualitative nature. It requires as main axles of the analysis the not explicit strategies of formation and the investigation teachers. It was used as support theoretical the studies of Lortie (1975), Huberman (2000), Zeichner and Liston (1993 and 1996), Shulman (2004), Bransford et al (2000), Mizukami et al (2003), Darlind-Hammond and Baratz-Snowden (2005), Hammerness, Darling- Hammond and Bransford, (2005), among others. The analyses of the teachers speaking had evidenced that the learnings of the teaching had given by means of the comment and of the creative imitation of the practical ones of its old teachers. They had pointed that the more the trought content approaches to the lived deeply context, more they have the facility of dealing with them. On the other hand, the more the content to be given moved away context lived deeply by the teachers, more difficulties they have in dealing with them. One still perceived that the new contents need some time to be assimilated and the teachers count on aid of the coleagues of the other schools to surpass such difficulties. One still perceived, that teachers who act in the rural schools in the city of Santarém, had on the basis of established the teaching. A in multisseries classrooms aspects little based theoretically. They seem to have slight knowledge of the general pedagogical knowledge and on it establish your teach. They dominate of precarious form beddings of specific knowledge the each teach and repeat what they had learned with its teachers (know, but do not know as they know). With the two weak axles, the base of knowledge for education is weak mechanics and stereotypicals (Shulman, 1986,1987). It was still proven that the limitation imposed for the absence of formal preparation for the exercise of magistery had shown imperative and the teachers had recognized this as one hindrance in its process of professional development
Foi com o trabalho que me tornei homem: trabalho, gênero e geração
(Universidade Federal de São Carlos, 2007-12-07) Perticarrari, Daniel; Lima, Jacob Carlos; https://lattes.cnpq.br/9244132532446607; https://lattes.cnpq.br/5533449825584711
The research had as objective to study how the increase on the number of women labor force has affected the division of the domestic work and the construction of the masculine social identity based in the provider paper, through the workers' perception on this change. This study examines the re-meaning or reiteration of the gender identities, having as cross section the generation insertion in the world of the work. Forty two metallurgic workers of São Carlos, SP (being thirty men and twelve women) had been interviewing, recovering the trajectories of life and work and their gender attributions, in the industrial and domestic space. The choice of the metallurgic sector elapsed for consisting in a space of masculine work historically recognized, being this profile changed, slowly, in last the two decades. It was possible to verify a generation cross section that delimits the position of the workers in relation to the work division and their expectation on their gender identity. It has been noticed that the oldest workers (with more than 40 years old), still see in the formal job market (with steady work and labor register) the privileged way of access in the labor and familiar structuring and the construction and valuation of the masculine identity. Presence of a speech of bigger equality between men and women was verified in workers between 30 to 39 years old. Finally, it was observed that young workers (until 29 years old) have greater propensity to insert themselves in the logic of transformations of flexible capitalism, marked for the instability in the labor trajectories. This context has influenced some changes in the gender perception in relation to the sexual division of the work and the biggest dubiousness of the construction of the masculine identity entailed to the work