Browsing by Author "Torres, Rodrigo"
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- ItemAbundances and morphotypes of the coccolithophore Emiliania huxleyi in southern Patagonia compared to neighbouring oceans and Northern Hemisphere fjords(COPERNICUS GESELLSCHAFT MBH, 2021) Diaz Rosas, Francisco; Alves de Souza, Catharina; Alarcon, Emilio; Menschel, Eduardo; Gonzalez, Humberto E.; Torres, Rodrigo; von Dassow, PeterCoccolithophores are potentially affected by ongoing ocean acidification, where rising CO2 lowers seawater pH and calcite saturation state (omega(cal)). Southern Patagonian fjords and channels provide natural laboratories for studying these issues due to high variability in physical and chemical conditions. We surveyed coccolithophore assemblages in Patagonian fjords during late spring 2015 and early spring 2017. Surface omega(cal) exhibited large variations driven mostly by freshwater inputs. High-omega cal conditions (max. 3.6) occurred in the Archipelago Madre de Dios. omega(cal) ranged from 2.0-2.6 in the western Strait of Magellan and 1.5-2.2 in the inner channel and was subsaturating (0.5) in Skyring Sound. Emiliania huxleyi was the only coccolithophore widely distributed in Patagonian fjords (> 96 % of total coccolithophores), only disappearing in the Skyring Sound, a semi-closed mesohaline system. Correspondence analysis associated higher E. huxleyi biomasses with lower diatom biomasses. The highest E. huxleyi abundances in Patagonia were in the lower range of those reported in Norwegian fjords. Predominant morphotypes were distinct from those previously documented in nearby oceans but similar to those of Norwegian fjords. Moderately calcified forms of E. huxleyi A morphotype were uniformly distributed throughout Patagonia fjords. The exceptional R/hyper-calcified coccoliths, associated with low omega(cal) values in Chilean and Peruvian coastal upwellings, were a minor component associated with high omega(cal) levels in Patagonia. Outlying mean index (OMI) niche analysis suggested that pH and omega(cal) conditions explained most variation in the realized niches of E. huxleyi morphotypes. The moderately calcified A morphotype exhibited the widest niche breadth (generalist), while the R/hyper-calcified morphotype exhibited a more restricted realized niche (specialist). Nevertheless, when considering an expanded sampling domain, including nearby southeast Pacific coastal and offshore waters, even the R/hyper-calcified morphotype exhibited a higher niche breadth than other closely phylogenetically related coccolithophore species. The occurrence of E. huxleyi in naturally low pH-omega(cal) environments indicates that its ecological response is plastic and capable of adaptation.
- ItemBecoming vegan: A study of career and habitus(SAGE PUBLICATIONS LTD, 2021) Giacoman, Claudia; Alfaro, Juan; Aguilera Bornand, Isabel Margarita; Torres, RodrigoThis article aims to understand the stages of adopting veganism in young people. To achieve this objective, we analyze 30 biographical interviews with young vegans in Santiago, Chile. The participant's stories allow us to identify that the transition to this new lifestyle implies acquiring a secondary habitus, that is, a gradual shift in understanding and acting in the world, which entails progressive identity changes until becoming vegan. This transition consists of five steps: personal questioning, vegetarianism attempt, vegetarianism, veganism, and activism. This path constitutes a career process but presents nuances according to the young people's social class of origin and individual characteristics. The main contribution of this article is to delve into the career stages that lead to the consolidation of a vegan identity, based on two classical sociological concepts (career and habitus).
- ItemDance to resist: emotions and protest in Lindy Hop dancers during October 2019 Chilean rallies(ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2021) Giacoman, Claudia; Torres, RodrigoOn 18 October 2019, a mass revolt began in Chile against the results of the neoliberal political and economic system. In the context of strong repression by the police, different artistic manifestations appeared as an expression of opposition to the government. This included concerts, performances, street theater and dance as political action. In this article, we present the case of a community of Lindy Hop dancers to explain the meaning given to dancing in public spaces as a protest action during this Chilean social crisis. Using an auto-ethnographic approach, we show that hoppers redefined their dance practices in public spaces as an act of resistance to state violence, from a political and an emotional perspective. However, these actions generated conflict within the hopper community, and the legitimacy of such practice was brought into question.
- ItemDETERMINATION OF LOW MOLECULAR WEIGHT CARBOHYDRATES IN CABERNET SAUVIGNON RED WINES(2009) Matsuhiro, Betty; Torres, Rodrigo; Zuniga, Elisa A.; Aguirre, Maria J.; Mendoza, Leonora; Isaacs Casanova, Mauricio
- ItemHacia un giro en las reformas educativas para una calidad equitativa.(2015) Torres Núñez, Pablo Enrique; Torres, Rodrigo; Facultad de Educación, Pontificia Universidad Católica de ChileUna serie de reformas se han incorporado a nuestro sistema escolar en las últimas décadas. Como producto de ellas se han logrado importantes avances en términos de cobertura y mejoramientos en resultados de aprendizajes, y más recientemente equidad. No obstante, nuestro sistema educativo sigue siendo en términos comparativos, un sistema de bajos resultados y de grandes desigualdades fuera del contexto latinoamericano. En este ensayo ofrecemos un análisis general del carácter de las reformas escolares llevadas a cabo hasta ahora y en carpeta. Proponemos un posible camino que pensamos sería beneficioso comenzaran a tomar futuras reformas. Para esta nueva etapa, creemos que las políticas educativas debieran perfilarse con foco en la calidad de los aprendizajes, dentro de un ámbito que vela por la equidad, o lo que podríamos denominar calidad equitativa. Para lograr esto argumentamos por la necesidad de girar el énfasis de las reformas escolares hacia los docentes y los procesos de enseñanza-aprendizaje. Estos son temas centrales que la evidencia internacional respalda como prioritarios y que forman parte central de nuestros estudios doctorales en Inglaterra desde la economía de la educación y la psicología educativa.
- ItemOvercalcified forms of the coccolithophore Emiliania huxleyi in high CO2 waters are not pre-adapted to ocean acidification(2017) Dassow, Peter von; Díaz Rosas, Francisco Javier; Bendif, El-Mahdi; Gaitan-Espitia, Juan-Diego; Mella-Flores, Daniella; Rokitta, Sebastian; John, Uwe; Torres, Rodrigo
- ItemSchool Segregation across the World: Has any progress been made in reducing the separation of the rich from the poor?(2020) Gutiérrez Cofre, Gabriel Jesús; Jerrim, John; Torres, RodrigoThe segregation of secondary school students into different schools has important implications for educational inequality, social cohesion and intergenerational mobility. Previous research has demonstrated how between-school segregation varies significantly across countries, with high levels of segregation occurring in central European nations that ‘track’ children into different schools and much lower levels in Scandinavia. This paper contributes to this literature by examining whether industrialised countries have made any progress in reducing levels of between-school segregation over time. Using six waves of data from the Programme for International student Assessment (PISA), this work shows how the segregation of rich and poor students has remained broadlyunchanged across OECD countries. This is despite major economic and political events occurring during this period, along with the introduction of numerous policy initiatives designed to reduce socioeconomic gaps. Therefore, the conclusions indicate that structural factors are likely to be the main drivers of between-school segregation (e.g.neighbourhood segregation or long-standing school admission policies) and that education policymakers may need to be much more radical if they are to foster greater levels of integration between the rich and the poor.
- ItemVibrational spectroscopy characterization and anticoagulant activity of a sulfated polysaccharide from sea cucumber Athyonidium chilensis(ELSEVIER SCI LTD, 2012) Matsuhiro, Betty; Osorio Roman, Igor O.; Torres, RodrigoExtraction of Athyonidium chilensis body wall afforded a light brown powder in 4.2% yield which was fractionated by ion-exchange chromatography. The main fraction F1 contained glucuronic acid, galactosamine and fucose in a molar ratio of 1.0:1.1:1.1, and 32.9% of sulfate group. The second derivative FT-IR spectroscopy and Surface-enhanced Raman scattering (SERS) give more information than the normal IR and Raman spectroscopies. The broad band in the normal FT-IR spectrum of F1 at 850.6 cm(-1) assigned to sulfate group was resolved in the second derivative spectrum into three bands at 856.4 cm(-1), 837.4 cm(-1) and 818.6 cm(-1) assigned to sulfate group attached to axial C4 and equatorial C2 and C6, respectively, in glycosidic residues. The most important bands in SERS of F1, but not observed in Raman spectrum are bands at 1648 cm(-1) (nu C=O), 1377 cm(-1) (delta C-H) assigned to methyl group of N-acetyl group, at 1173 cm(-1) and at 956.2 cm(-1) (nu C-O-C) of glycosidic linkage: and bands at 925.5 cm(-1) and 890.4 cm(-1) (delta C-1-H) assigned to a and beta anomeric configurations of glycosidic residues, respectively. By NMR studies, glycosidic linkages and sulfation pattern of F1 was confirmed. Results obtained indicated that fraction F1 is chondroitin 4,6-disulfate substituted at position O-3 of glucuronic acid by partially 2,4-disulfated alpha-fucopyranosyl residues. Moreover, the anticogulant activity, measure in APTT of F1 showed at low concentration, a good correlation with heparin. (C) 2012 Elsevier Ltd. All rights reserved.