Resumo Uma das contribuições fundamentais da perspectiva bourdieusiana é a proposta de uma teoria da prática como resultado da relação dialética entre significado objetivo e significado vivido, o que implica uma tomada de posição que é, ao mesmo tempo, epistemológica, teórica e metodológica. Neste texto, vamos primeiro explicar esses aspectos e, em seguida, no âmbito de uma pesquisa sobre a desigualdade social em Córdoba, vamos propor uma maneira de articular os dois sentidos, com foco em estratégias educacionais e enfatizando suas conseqüências metodológicas.

Abstract One of the fundamental contributions of the Bourdieusian perspective is its proposal of a theory of practice as a result of the dialectical relation between objective meaning and experiential meaning, which implies a position taking that is, at the same time, epistemological, theoretical and methodological. In this text, we will first explain these aspects and then, within the framework of a research on social inequality in Córdoba, we will propose a way to articulate both senses, focusing on educational strategies and emphasizing their methodological consequences.

Resumen Uno de los aportes fundamentales de la perspectiva bourdieusiana es su propuesta de una teoría de la práctica como resultado de la relación dialéctica entre sentido objetivo y sentido vivido, lo que implica una toma de posición que es, a la vez, epistemológica, teórica y metodológica. En este texto, explicitaremos primero estos aspectos y luego, en el marco de una investigación sobre la desigualdad social en Córdoba, propondremos una manera de articular ambos sentidos, focalizando en las estrategias educativas y haciendo hincapié en sus consecuencias metodológicas.

Forest environments have continuously existed in Antarctica since the late Paleozoic and only disappeared from this continent since the Neogene. Nevertheless, the structure of these forests underwent substantial evolutionary changes. During the late Cretaceous, forests dominated by conifers and pteridophytes were gradually replaced by angiosperm-dominated forests. Elements common to these Antarctic forests are important constituents of the recent Valdivian Forest. During the Turonian stage of the Late Cretaceous, the Antarctic Peninsula and Patagonia were reconnected by a land bridge after a separation since the end of the Jurassic. Using biogeographic tools applied to the palynological and leaf imprint record, outcrops of Campanian-Maastrichtian age were studied from the Snow Hill, James Ross and Seymour (Marambio) Islands in the James Ross basin, Antarctica; Skua Bay, Half Three Point, Price Point and Zamek Hill on King George Island, Antarctica, and Rocallosa Point, Cerro Guido, Las Chinas, Dorotea Hill, Cazador Hill and La Irene in Chilean-Argentinian Patagonia, comparing the current distribution and the paleogeography, as well as the influence of potential areas of endemism and vicariants events. The analysis indicates that vegetation evolved under environmental conditions subject to intense volcanic and climatic disturbances, with changes from a period with extreme greenhouse climate (Turonian-Campanian) to strong cooling during the Maastrichtian. We suggest that a continuous forest existed in southern South America and Antarctica, which was shaped during the Latest Cretaceous by the presence of marine basins and and intermittent connection and disconnection of the flora.

Se sabe que al menos desde fines del Paleozoico ambientes boscosos habrían existido en la Antártica y habrían desaparecido de ella solo a fines del Terciario. Sin embargo, la estructura no ha sido la misma, evolucionando desde un bosque dominado por coníferas y pteridófitas durante el Cretácico Inferior, a bosques dominados por angiospermas a partir del Cretácico Superior, con elementos comunes a los constituyentes actuales de la Selva Valdiviana. Durante el Turoniano la Península Antártica y Patagonia se reunieron por un puente terrestre rompiendo millones de años de desconexión, y gracias a una variedad de ambientes de sedimentación, se han conservado numerosos vestigios de la flora que cubrió ambos subcontientes. Mediante herramientas biogeográficas aplicadas al registro palinológico y de improntas foliares, afloramientos campaniano-maastrichtianos de islas Snow Hill, James Ross y Seymour (Marambio), en la cuenca de James Ross, Antártica; bahía Skúa, punta Half Three, punta Price y cerro Zamek, en la isla Rey Jorge, Antártica; y punta Rocallosa, cerro Guido, Las Chinas, cerro Dorotea, cerro Cazador y La Irene en la Patagonia chileno-argentina, se estudió la relación entre la distribución actual y la paleogeografía, considerandolos potenciales eventos vicariantes y áreas de endemismo establecidas. Reconstrucciones paleoecológicas muestran que los elencos vegetacionales habrían evolucionado en el marco de ambientes sometidos a intensa perturbación volcánica y climáticamente habrían estado sometidos a uno de los lapsos más cálidos de la historia natural, pero con fuertes pulsos de enfriamiento durante el Campaniano y Maastrichtiano. Se sostiene que entre el Maastrichtiano y el Eoceno, existió un continuo forestal entre Patagonia y Sudamérica que habría sido modelado por la presencia de las cuencas marinas finicretácicas y la intermitente conexión-desconexión de las floras.

Zn-EDTA degradabilty by catechol-driven Fenton reaction was studied. Response surface methodology central composite design was employed to maximize this complex degradation. Theoretical speciation calculations were in good agreement with the experimental results. Fenton and Fenton type treatments are typically thought to be applicable only in the highly acidic range, representing a major operational constraint. Interestingly, at optimized concentrations, this CAT-driven Fenton reaction at pH 5.5 achieved 100% Zn-EDTA degradation; 60% COD and 17% TOC removals, using tiny amounts of CAT (50 µM), Fe(III) (445 µM) and H2O2 (20 mM) with no evident ferric sludge.