Browsing by Author "Castro, Camila"

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    A new species of Alsodes (Anura: Alsodidae) from Altos de Cantillana, central Chile
    (MAGNOLIA PRESS, 2015) Charrier, Andres; Correa, Claudio; Castro, Camila; Mendez, Marco A.
    Based on morphological and molecular evidence (mitochondrial and nuclear sequences) we describe a new species of spiny-chest frog, Alsodes cantillanensis, from central Chile (around 34 degrees S). The type locality, Quebrada Infiernillo, is located in the Coastal Range at approximately 65 km from Santiago (Metropolitan Region), the capital of Chile. The distribution of the new species is included entirely in that of A. nodosus (32-36 degrees S approximately), which was identified as the sister taxon according to molecular phylogenetic analyses. Moreover, both species are sympatric in the type locality. The new species was found in a Nothofagus macrocarpa relict forest potentially threatened by gold mining activities. We identify other threats for its conservation and some biological data needed for understanding the evolution of this species. This discovery reveals the scarce knowledge about biogeography, evolution and ecology of spiny- chest frogs from central Chile.
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    Characterization of Extracellular Polymeric Substances Produced by an Acidianus Species and Their Relevance to Bioleaching
    (2023) Castro, Camila; Donati, Edgardo R.; Vera, Mario
    Extracellular polymeric substances (EPS) produced by microorganisms play a crucial role in various bioprocesses, including bioleaching. The microbial leaching of metal sulfides requires an initial cell attachment, which is facilitated by EPS. These substances are mixtures of polysaccharides, proteins, lipids, and other compounds, and their composition and properties can vary depending on the species, growth conditions, and environmental factors. Despite the significance of iron/sulfur oxidizing species in biomining processes, the knowledge of the interfacial processes between thermoacidophilic archaeal species and mineral surfaces is limited. This study examines the cell surface characteristics and EPS produced by an Acidianus strain. The research was conducted using microscopic techniques, Zeta-potential measurements, spectrophotometric methods, Fourier transform infrared spectroscopy, and fluorescence lectin-binding analysis. The results suggest that non-soluble substrates, such as sulfur or pyrite, induce changes in cell surface structures, including the presence of cell appendages, wider cell envelopes, higher hydrophobicities, and increased EPS production, compared to cells grown with soluble substrates such as tetrathionate or ferrous iron. The EPS mainly consist of proteins and carbohydrates, including glucose, manose, N-acetylgalactosamine, and N-acetylglucosamine residues. This study contributes to a better understanding of the relationship between thermophilic archaea and mineral surfaces in biomining processes.
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    Testing of a Drawing Toy for Children with Blindness: The Kuwu Experience
    (2021) Escobar, Jose-Pablo; Castro, Camila; Garolera, Marion; Sepulveda, Angelica; Santa Cruz, Martin; Rosas, Ricardo
    Play is a fundamental activity in early childhood and a source of cognitive development. One ludic activity in early childhood is drawing, a semiotic activity in which children can build and transform symbols and meanings in a way to reflect their thoughts and emotions. However, drawing has a visual component that is a challenge for some children with blindness or visual impairment. This research aims to evaluate a prototype of a haptic pencil called Kuwu. Through user's usability tests and expert heuristic inspection, we evaluated 10 children with blindness or visual impairments between 5 and 8 years old, from 2 schools of Santiago, Chile. Heuristics evaluation shows the minimalist design, ease, and flexibility of use of the pencil that allows children to draw independently. Usability testing is a foundational phase in any technological development, especially when creating from a universal design perspective.