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Search Results: 1 - 10 of 288824 matches for " Maria Célia;Tenenbaum "
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The phytoplankton of Guanabara Bay, Brazil: I. historical account of its biodiversity
Villac, Maria Célia;Tenenbaum, Denise Rivera;
Biota Neotropica , 2010, DOI: 10.1590/S1676-06032010000200030
Abstract: this is a historical account of the biodiversity of phytoplankton in guanabara bay, brazil. it is based on 57 publications that refer to sampling carried out between 1913 and 2004. the publications included are those with direct microscopic identification. although 80% of the studies focus on ecological issues that tend to mention only the most abundant species, 24 publications provide comprehensive check-lists at the species level, especially of taxa > 20 μm. the inventory of species includes, to date, 308 taxa among 199 diatoms, 90 dinoflagellates, 9 cyanobacteria, 5 euglenophyceans, 1 chlorophycean, 1 prasinophycean, 1 silicoflagellate, and 2 ebriids. the most conspicuous species were the dinoflagellate scrippsiella trochoidea and diatoms from the skeletonema costatum complex. the first was the theme of the very first publication in the area (faria 1914) that reported on its bloom associated with the mass mortality of fish due to oxygen depletion; it is still often found in high abundances (106 cell.l-1) in more protected areas. the second was long considered in the literature as a cosmopolitan and opportunistic species, until the recent discovery of cryptic species within the genus; taxonomic re-evaluation of local populations is, therefore, needed. besides these two species, only other 25 species stood out in terms of frequency of occurrence and widespread distribution in the bay, some known to be implicated in harmful blooms elsewhere. the biodiversity of dinoflagellates, especially within the gymnodiniales, and that of other unidentified flagellates (haptophyceae, cryptophyceae, prasinophyceae, raphidophyceae) is largely underestimated because of the use of fixatives that distort/destroy diagnostic characters. from the initial inventory of 124 taxa published in 1917 and the subsequent additions in species numbers, one can have a false perception that the phytoplankton biodiversity has increased throughout the years, despite the overall increase in eutrophicat
Auto- and heterotrophic nanoplankton and filamentous bacteria of Guanabara Bay (RJ, Brazil): estimates of cell/filament numbers versus carbon content
Santos, Viviane Severiano;Villac, Maria Célia;Tenenbaum, Denise Rivera;Paranhos, Rodolfo;
Brazilian Journal of Oceanography , 2007, DOI: 10.1590/S1679-87592007000200006
Abstract: variations of nanoplankton (2-20 μm) and filamentous bacteria (diameter: 0.5-2.0 μm) of guanabara bay (rj, brazil) are presented, considering cell density and carbon content of auto- and heterotrophs. our goal is to contribute to future modeling of local trophic dynamics. subsurface water samples were taken weekly during the year 2000 at two sites: urca (close to the entrance, more saline, eutrophic) and ramos (inner area, less saline, hypertrophic). microscopic analysis was done by epifluorescence and cell density was converted to biomass through cell biovolume. total nanoplankton was about 108 cells.l-1 in most samples (>57%), and total filamentous bacteria densities varied from 105 to 108 fil.l-1. autotroph density was one order of magnitude higher at ramos, both for nanoplankton (md: 108cells.l-1 at ramos and 107cells.l-1 at urca) and for filamentous bacteria (md: 106 fil.l-1 at ramos and 105 fil.l-1 at urca). the same was observed for autotrophic biomass (md: 103μgc.l-1 at ramos and 101μgc.l-1 at urca for nanoplankton; md: 28μgc.l-1 at ramos and 1.4μgc.l-1 at urca for filamentous bacteria). the relative contribution of autotrophs increased after conversion to biomass. seasonal variation was conspicuous for filamentous bacteria at both sites and for nanoplankton only at ramos, with maximum autotrophic abundances during the rainy period (spring-summer).
Protozooplankton characterization of two contrasting sites in a tropical coastal ecosystem (Guanabara Bay, RJ)
Gomes, Eli Ana Traversim;Santos, Viviane Severiano dos;Tenenbaum, Denise Rivera;Villac, Maria Célia;
Brazilian Journal of Oceanography , 2007, DOI: 10.1590/S1679-87592007000100004
Abstract: much time and resources have been invested in understanding plankton dynamics in guanabara bay (brazil), but no attention has been devoted to the protozooplankton. to fulfill this lacuna, abundance and composition of protozooplankton were investigated from january to december - 2000 in fortnightly surface water samplings at two distinct water quality sites (urca - closer to the bay entrance, more saline and cleaner waters; ramos - inner reaches, hypereutrophic waters). the density at urca (103 - 105 cell.l-1) was one to three orders of magnitude lower than at ramos (104 - 105 cell.l-1). a seasonal trend for nanoplankton and protozooplankton was more evident at urca, but both sites had lower densities during the colder period. small heterotrophic dinoflagellates (20-30 mm) were dominant in over 50% of the samples. the protozooplankton abundance and composition reflected the distinct trophic conditions states found at the bay. during the wet-warm season, non-oligotrich ciliates were representative of ramos site with gymnodiniaceae dinoflagellates, while tintinnids and heterotrophic dinoflagellates were predominantly found at urca mainly during the dry-cold season. this first descriptive study towards the understanding of the intricate relationships among the microbial food web components reveals that protozooplankton can be a good indicator of water quality conditions at the bay.
Releitura da Biblioteca Nacional
Portella, Célia Maria;
Estudos Avan?ados , 2010, DOI: 10.1590/S0103-40142010000200016
Abstract: history and memory of the national library. the concept of public and national library. integration between physical and digital library. reading and citizenship. transparency. accessibility. a new conception of the national library foundation, based upon an unitarian structure of time, wich holds past present and future, wich gathers a retropective, perspective and prospective approach. lesson and life of the national library foundation.
Higher Education in Brazil and the policies for increasing the number of vacancies from Reuni: advances and controversies
Maria Célia Borges
Educa??o : Teoria e Prática , 2012,
Abstract: This paper presents a discussion on the policies to expand Higher Education, stating the influences of neoliberalism and explaining the contradictions in legislation and reforms at this level of education in Brazil after the 1990s. It questions the model of the New University with regard to the Brazilian reality and the poor investments available for such a reform. It calls attention to the danger of prioritizing the increase in the number of vacancies instead of the quality of teaching, something which would represent the scrapping of the public university. It highlights the contradictions of Reuni, with improvised actions and conditioning of funds, through the achievement of goals. On one hand, it recognizes the increasing number of vacancies in Higher Education and, on the other, it reaffirms that democratization of access requires universities with financial autonomy, well-structured courses with innovative curricula, qualified professors, adequate infrastructure, and high quality teaching, with research aiming the production of new knowledge, as well as university extension.
Marxism and literature Marxismo e literatura
Maria Célia Leonel
Estudos de Sociologia , 2007,
Saberes docentes e forma??o de professores: um breve panorama da pesquisa brasileira
Educa??o & Sociedade , 2001, DOI: 10.1590/S0101-73302001000100003
Abstract: the researches about teacher's education and profession point to a comprehension's revision of pedagogical practice of the teacher who is consider as a professional knowledge mobilizer. it consider so, that this, in your trajectory, build and rebuild your knowledge as according to the necessity of your utilization, your experiences, your professional and formative routes, etc. the objective of this text is present analysis of how and when the question of teachers knowledge appears on researches about teacher's education in the brazilian educational literature, identifying the different references and theoretical-methodological approaches that justify them, the focus and typology utilized and created by brazilian researchers. it believes that the investigations of this thematic will allow identify a way of research developed with own characteristics, but in time with a international tendency in the scope of researches about teaching and about teachers.
Reforma do Estado e reforma de sistemas de saúde: experiências internacionais e tendências de mudan?a
Almeida,Célia Maria de;
Ciência & Saúde Coletiva , 1999, DOI: 10.1590/S1413-81231999000200004
Abstract: this text discusses the agenda for reform of the state, assessing the central themes and the difficulties facing implementation; it identifies the forms it takes in models being implemented in the area of health care and analyzes some countries' reforms (usa, united kingdom and colombia). it also points to approaches emerging as trends in proposals for sector reform in brazil, vis a vis the international experience, where the idea of split between financing and provision functions has been flourished, and that introducing competition mechanisms into resource allocation has been hardly criticized. although beginning from far more precarious conditions, latin american reforms have been more radical and accompanied by extreme financial constraints, with substantial under-funding of the sector. one trend in the region is towards the increasing likelihood of previous systems being dismantled with no guarantee of substantive improvements in coverage or equity, either because of the radicalism of the processes, or because of the high degree of experimentation with which reforms are being implemented.
A critical discourse analysis approach to news discourses and social practices on race in Brazil
Magalh?es, Célia Maria;
DELTA: Documenta??o de Estudos em Lingüística Teórica e Aplicada , 2006, DOI: 10.1590/S0102-44502006000200003
Abstract: in this paper i set out from brazilian social theories on race to analyse a contemporary corpus of news reports in a brazilian broadsheet newspaper. the aim is investigating change in mediated discourses on race. based on critical discourse analysis (cda) and with the help of corpus linguistics methodological tools i focus on lexical items used to categorise race, the semantic relations created and their association with discourse representation in the newspaper. the combined analysis of semantic relations and interdiscursivity has allowed for the perception of tensions over the use of terms from different semantic fields to categorize race and of conflicting discourses of race classification in the paper. the analysis has also allowed for a cautious interpretation of dialogicality and of different orientations to racial difference, following the social research inventories in fairclough (2003) in the reports.
Deslocamentos intra-urbanos e estrutura??o socioespacial na metrópole brasiliense
Caiado, Maria Célia Silva;
S?o Paulo em Perspectiva , 2005, DOI: 10.1590/S0102-88392005000400004
Abstract: the objective of this paper is to evaluate the alterations in the distribution and in the socio spatial mobilite of the population that may be associated to the urbanization process and to the intra urban structuring in the ride _ integrated region of development of federal district and adjacency. the ride presents specific characteristics related to the process of economical development, to the territorial occupation and to the urban administration, which differs it from the other urban agglomerations and from the national metropolitan areas, resembling itself however, as for the inaqualities in the process of socio spatial distribution of the population.
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