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Fitness surfaces and local thermal adaptation in Drosophila along a latitudinal gradient
(2024) Alruiz Herrera, José Manuel; Peralta Maraver, Ignacio; Cavieres Parada, Grisel Beatriz; Bozinovic Kuscevic, Francisco; Rezende Landaeta, Enrico
Local adaptation is commonly cited to explain species distribution, but how fitness varies along continuous geographical gradients is not well understood. Here, we combine thermal biology and life-history theory to demonstrate that Drosophila populations along a 2500 km latitudinal cline are adapted to local conditions. We measured how heat tolerance and viability rate across eight populations varied with temperature in the laboratory and then simulated their expected cumulative Darwinian fitness employing high-resolution temperature data from their eight collection sites. Simulations indicate a trade-off between annual survival and cumulative viability, as both mortality and the recruitment of new flies are predicted to increase in warmer regions. Importantly, populations are locally adapted and exhibit the optimal combination of both traits to maximize fitness where they live. In conclusion, our method is able to reconstruct fitness surfaces employing empirical life-history estimates and reconstructs peaks representing locally adapted populations, allowing us to study geographic adaptation in silico.
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Formación inicial docente, currículum y sistema escolar: ¿cuál es el lugar de los niños y adolescentes inmigrantes no hispano hablantes en el sistema educativo chileno?
(2022) Toledo Vega, Gloria Macarena; Cerda Oñate, Karina; Lizasoain, Andrea
En esta nota se discute la situación escolar de los inmigrantes no hispanohablantes haitianos en el sistema educativo chileno. Se exploran cuatro dimensiones asociadas a la trayectorias escolares de los inmigrantes haitianos en la escuela chilena: (a) la situación general de la comunidad haitiana en Chile; (b) el currículum de Lengua y Literatura de enseñanza primaria y secundaria y la enseñanza del español como lengua adicional; (c) la Formación Inicial Docente (FID) y la inclusión del español como lengua extranjera en las mallas curriculares; (d) los sistemas de evaluación del desempeño y de ordenamiento de los establecimientos escolares y sus consideraciones respecto de los estudiantes inmigrantes no hispanohablantes. Se concluye con la necesidad de desarrollar e implementar políticas de inclusión para los inmigrantes haitianos que incluyan el currículum escolar, la formación inicial docente, y los sistemas de evaluación de calidad del sistema escolar chileno, con el fin de hacer que las escuelas chilenas sean espacios de apoyo e inclusión para todos los habitantes de Chile.
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Autopolyploidization and in vitro regeneration of three blueberry cultivars from leaves and microstems
(2024) Jarpa Tauler, Gabriela Teresa; Martínez Barradas, Vera Isabel; Romero Romero, Jesús Lucina; Arce Johnson, Patricio
Blueberries are a fruit with an increasing global demand due to their phytochemical and bioactive compounds content. They are promoted worldwide because of their health benefits. For optimal growth and productivity, blueberry crops need acidic soil pH, specific chilling hours, and an adequate atmospheric temperature. This delicate production equilibrium is under severe threat from climate change, potentially leading to reduced yields and increased cultivation costs unless new cultivars are developed for each edafoclimatic zone. Therefore, considering varietal replacements with more productive cultivars offering higher quality and better adaptability to local conditions is imperative. In this study, we employ polyploidization and in vitro tissue culture to promote variability and lay the foundation for new cultivar development. We report the successful induction of octoploids in three blueberry cultivars, namely 'Biloxi,' 'Legacy,' and 'Duke', through whole-genome duplication. Leaves and microstem explants were exposed to 0.1% colchicine for 24 and 48 hours in in vitro culture. After analyzing the polyploid level of 160 regenerated shoots using DNA flow cytometry, we obtained a total of 18 mutants, consisting of 8 mixoploids and 10 octoploids. The number of chloroplasts in the stomata was analysed by fluorescence microscopy, revealing the duplication of these organelles in the induced octoploid plants. To our knowledge, this represents the first successful induction of octoploids in three blueberry cultivars -'Biloxi,' 'Legacy,' and 'Duke'- achieved by exposing leaves and microstem explants to colchicine in in vitro culture. This technique holds promise as a valuable tool for the development of improved blueberry cultivars.
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Quantum measurement transition and entanglement of trapped ions and optomechanical systems
(2024) Araya Sossa, Kevin Jordan; Orszag Posa, Miguel; Pontificia Universidad Católica de Chile. Instituto de Física
Although quantum mechanics has been able to explain a wide range of physical, chemical, and even biological events with unprecedented accuracy, fundamental problems remain. For instance, the problem of quantum measurement and quantum entanglement, which are the most perplexing problems that have persisted since the foundation of quantum mechanics. Both are crucial quantum resources with broad applications in quantum information science, quantum computing and quantum optics. For this reason, this thesis is devoted to research the quantum measurement from the weakest regime to the strongest one as well as the dynamics of entanglement of different quantum systems. In this work, we study the measurement transition for a coherent-squeezed pointer state
through a transition factor Γ that involves a system-pointer coupling by using an arbitrary measured observable A. In addition, we show that the shift in the pointer’s position and momentum establishes a relationship with a new value defined as the transition value, which generalizes the weak value as well as the conditional expectation value. Furthermore, a new strategy is introduced to achieve different measurement regimes by just adjusting the r and ϕξ parameters of the coherent-squeezed pointer state, opening an interesting way to test quantum mechanics foundations. Our scheme has been theoretically applied in a trapped ion illuminated by a bichromatic laser beam, with a high potential to be implemented in future experimental setups. Besides, we propose a method to regulate the quantum entanglement in the system mentioned before as well as a dispersive-hybrid system where a qubit is directly coupled to a cavity and a mechanical resonator. Entanglement can be controlled by only tuning the squeezing parameters associated with the vibrational mode. As the squeezing amplitude becomes larger, the maximal entanglement abruptly falls to zero at specific squeezing phases. For the hybrid system, it is also possible to generate entanglement for bipartitions from the qubit-cavity-resonator system after applying this strategy. Entangled qubit-cavity states are created through squeezing, even though there is no direct interaction between them. We also analyze the effect of atomic, optical, and vibrational losses on the quantum entanglement. We finally discuss our schemes to be implemented in future experimental setups and promote further studies to generalize the concept of “monogamy of entanglement” in tripartite systems outside qubit-composite states, in particular, (2 ⊗ 2 ⊗ n)-dimensional systems.
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Análisis de la historia de Griselda del Decamerón desde una reescritura protofeminista realizada por Eleanora Louisa Hervey
(2024) Bardin Quesieh, María Fernanda; Goellner, Letícia Vieira de Souza; Pontificia Universidad Católica de Chile. Facultad de Letras
Esta investigación pretende ampliar los estudios del libro The Feasts of Camelot: with the Tales that Were Told There (1863) de la escritora victoriana Eleanora Louisa Hervey, quien ha sido históricamente relegada del canon literario. En este sentido, las escasas investigaciones sobre su obra, llevadas a cabo en su mayoría por la académica Renée Ward, han demostrado un interés por recuperar a esta autora y sus escritos; sin embargo, sigue existiendo un gran vacío respecto a esta materia. En la presente investigación se busca evaluar, a partir de la intertextualidad, si la obra mencionada se puede catalogar como una reescritura protofeminista bajo una perspectiva traductológica enfocada en la traducción feminista (Flotow, 1991, 1997, 2019; Castro, 2008). De este modo, se analizó la reescritura de la historia de Griselda que se encuentra en los capítulos VI y VII de The Feasts of Camelot, a partir de su comparación y contraste con tres textos: la versión de la historia de Griselda presentada primero, en el capítulo “Décima Narración” de la “Décima Jornada” del Decamerón de Boccaccio, y las reescrituras posteriores realizadas por Petrarca y Chaucer. Debido a la inclusión de cambios temáticos y de focalización en la narración de Hervey que se vinculan a estrategias de traducción feminista como el secuestro, la retraducción y la selección estratégica de textos, la investigación dio como resultado que la historia de Griselda presente en la obra de Hervey constituye una reescritura protofeminista.