Proyectos

Plants, with their two-layered immune system, are equipped to combat pathogen invasion. The first layer, Pattern Triggered Immunity (PTI), is a powerful defense mechanism. It relies on Pattern Recognition Receptors (PRRs) to detect Microbe-Associated Molecular Patterns (MAMPs) from microbes, triggering a robust defense response. This response, including signaling cascades, gene expression changes, and production of antimicrobials and defense hormones, contributes to restricting pathogen colonization. PTI activation can trigger a systemic response known as Induced Systemic Resistance (IRS), enhancing plant defenses throughout the organism and leading to Non-Host-Resistance. The potential of PTI activation to enhance a plant's overall defensive capacity is a promising strategy to improve crop health. PTI activation at infection sites triggers the production of mobile signals within the plant, which then spread IRS throughout the plant, enhancing its overall defensive capacity. Flg22 and xyn11, two well-known MAMPs, trigger PTI in tomato, activating various defense responses and, interestingly, including IRS in tomatoes and other plants. Plant roots, often overlooked in discussions of plant immune systems, possess their own immune system, though less potent than leaves. They respond to MAMPs like Flg22 and chitin, but with weaker production of defense chemicals. Despite this difference, roots activate various defenses like PR proteins and callose deposition. Uniquely, roots secrete antifungal secondary metabolites like flavonoids. These root exudates play a crucial role in shaping the surrounding microbiome, attracting beneficial microbes, and possess antimicrobial activity itself. Studies have shown that root exudate composition can be manipulated to influence the soil microbiome and potentially enhance plant growth. This underlines the importance of considering roots in our understanding of plant immune systems, particularly how defense responses are displayed in the root after immune activation in leaves in terms of a systemic immune response. This often overlooked aspect is crucial for a comprehensive understanding of plant immunity. Plants and microbes communicate two-way, establishing an interaction, by instance, plant root exudates influence the composition of the rhizosphere microbiome, which in turn regulates plant growth and immunity. Research suggests that specific bacteria within the rhizosphere microbiome can enhance plant immunity. In fact, transplanting the microbiome from a resistant tomato variety to a susceptible one improved disease resistance. Understanding this plant-microbiome-soil interaction is crucial for developing sustainable agriculture. Our ongoing research investigates how soil type influences tomato immunity and its connection to the soil microbiome. Preliminary results show that different soil types affect the strength of plant immunity responses, even though the overall bacterial types (phyla) are similar. Interestingly, specific bacterial isolates from a soil type with higher immunity were able to directly trigger plant defense mechanisms. Unraveling the intricate interplay between soil type, the rhizosphere microbiome, and tomato immunity holds the key to unlocking sustainable and resilient agricultural practices. This proposal aims to investigate the potential of targeted Pattern-Triggered Immunity (PTI) activation in tomato leaves to enhance plant defense against diverse pathogens. We hypothesize that leaf application of microbial elicitors (flg22 and Xyn11) will trigger PTI, leading to changes in root gene expression and root exudate composition. These alterations are expected to enrich beneficial bacteria in the rhizosphere microbiome, ultimately enhancing resistance against both the foliar pathogen Pseudomonas syringae pv. tomato and the soil-borne pathogen Fusarium oxysporum f.sp. lycopersici. To achieve this, we have defined three specific objectives: 1) Evaluate the impact of leaf-applied elicitors on pathogen susceptibility, root gene expression, root exudate composition, and soil microbiome composition. 2) Develop synthetic exudates mimicking PTI-activated plants and construct synthetic microbial communities potentially containing beneficial bacteria. 3) Assess the effectiveness of leaf-applied elicitors and synthetic microbial communities on the root microbiome and plant health under field conditions. With this, we aim to elucidate the mechanisms by which leaf-based PTI activation influences root-level processes and shapes the rhizosphere microbiome to enhance tomato plant defense against various pathogens. The findings hold promise for developing novel and sustainable strategies for disease management in tomato production.

Plants, with their two-layered immune system, are equipped to combat pathogen invasion. The first layer, Pattern Triggered Immunity (PTI), is a powerful defense mechanism. It relies on Pattern Recognition Receptors (PRRs) to detect Microbe-Associated Molecular Patterns (MAMPs) from microbes, triggering a robust defense response. This response, including signaling cascades, gene expression changes, and production of antimicrobials and defense hormones, contributes to restricting pathogen colonization. PTI activation can trigger a systemic response known as Induced Systemic Resistance (IRS), enhancing plant defenses throughout the organism and leading to Non-Host-Resistance. The potential of PTI activation to enhance a plant's overall defensive capacity is a promising strategy to improve crop health. PTI activation at infection sites triggers the production of mobile signals within the plant, which then spread IRS throughout the plant, enhancing its overall defensive capacity. Flg22 and xyn11, two well-known MAMPs, trigger PTI in tomato, activating various defense responses and, interestingly, including IRS in tomatoes and other plants. Plant roots, often overlooked in discussions of plant immune systems, possess their own immune system, though less potent than leaves. They respond to MAMPs like Flg22 and chitin, but with weaker production of defense chemicals. Despite this difference, roots activate various defenses like PR proteins and callose deposition. Uniquely, roots secrete antifungal secondary metabolites like flavonoids. These root exudates play a crucial role in shaping the surrounding microbiome, attracting beneficial microbes, and possess antimicrobial activity itself. Studies have shown that root exudate composition can be manipulated to influence the soil microbiome and potentially enhance plant growth. This underlines the importance of considering roots in our understanding of plant immune systems, particularly how defense responses are displayed in the root after immune activation in leaves in terms of a systemic immune response. This often overlooked aspect is crucial for a comprehensive understanding of plant immunity. Plants and microbes communicate two-way, establishing an interaction, by instance, plant root exudates influence the composition of the rhizosphere microbiome, which in turn regulates plant growth and immunity. Research suggests that specific bacteria within the rhizosphere microbiome can enhance plant immunity. In fact, transplanting the microbiome from a resistant tomato variety to a susceptible one improved disease resistance. Understanding this plant-microbiome-soil interaction is crucial for developing sustainable agriculture. Our ongoing research investigates how soil type influences tomato immunity and its connection to the soil microbiome. Preliminary results show that different soil types affect the strength of plant immunity responses, even though the overall bacterial types (phyla) are similar. Interestingly, specific bacterial isolates from a soil type with higher immunity were able to directly trigger plant defense mechanisms. Unraveling the intricate interplay between soil type, the rhizosphere microbiome, and tomato immunity holds the key to unlocking sustainable and resilient agricultural practices. This proposal aims to investigate the potential of targeted Pattern-Triggered Immunity (PTI) activation in tomato leaves to enhance plant defense against diverse pathogens. We hypothesize that leaf application of microbial elicitors (flg22 and Xyn11) will trigger PTI, leading to changes in root gene expression and root exudate composition. These alterations are expected to enrich beneficial bacteria in the rhizosphere microbiome, ultimately enhancing resistance against both the foliar pathogen Pseudomonas syringae pv. tomato and the soil-borne pathogen Fusarium oxysporum f.sp. lycopersici. To achieve this, we have defined three specific objectives: 1) Evaluate the impact of leaf-applied elicitors on pathogen susceptibility, root gene expression, root exudate composition, and soil microbiome composition. 2) Develop synthetic exudates mimicking PTI-activated plants and construct synthetic microbial communities potentially containing beneficial bacteria. 3) Assess the effectiveness of leaf-applied elicitors and synthetic microbial communities on the root microbiome and plant health under field conditions. With this, we aim to elucidate the mechanisms by which leaf-based PTI activation influences root-level processes and shapes the rhizosphere microbiome to enhance tomato plant defense against various pathogens. The findings hold promise for developing novel and sustainable strategies for disease management in tomato production.

The primary objective of this research is to evaluate the feasibility of using ultrasonic acoustic imaging as a non-intrusive, in situ technique to assess the plastic behavior of commercial metals and alloys. Specifically, it aims to explore the potential of ultrasonic acoustic imaging to identify and monitor various plastic deformation mechanisms in stainless steel and aluminum. The selection of materials is based on their distinct plastic deformation behaviors: aluminum releases internal energy through dislocation mechanisms, while stainless steel releases energy through deformation, first by dislocation and then by twinning. To achieve this goal, the study will continuously measure changes in sound velocity and the nonlinear acoustic parameter β while subjecting the materials to uniaxial tensile tests at different levels of applied stress. Previous studies conducted by our research group have demonstrated that changes in sound velocity, in relation to strain, offer a reliable means of quantifying dislocation density in local measurements on aluminum, copper, and stainless steel specimens. Furthermore, these studies have observed that alterations in the nonlinear acoustic parameter, specifically second harmonic generation, exhibit more pronounced changes compared to variations in linear acoustics (speed of sound). Building upon these findings, the proposed research involves the generation of both linear and nonlinear acoustic images over wider spatial regions to advance our understanding of the plastic behavior of materials undergoing different microstructural changes. The challenge of applying the results of this research to in situ measurements in the industry is not trivial, as the highly controlled laboratory conditions are not maintained in service components. In this regard, the incorporation of machine learning tools in the proposal aims to identify the parameters most sensitive to the various deformation mechanisms through clustering techniques. It is expected that the correlation of different acoustic parameters with the various plastic deformation mechanisms of both materials under study will generate an optimal database that reflects the variety of scenarios present in service components, thus paving the way for the industrial use of the proposed characterization system. The adoption of diagnostic techniques and the utilization of metallic material state analysis in service significantly enhance our ability to comprehend and control plastic deformation mechanisms, contributing to improved material reliability and robustness, and facilitating informed decision-making and maintenance strategies. Additionally, ex-situ standard microstructural tests, including XRD (X-ray diffraction), EBSD (electron backscatter diffraction), and TEM (transmission electron microscopy), will be performed to characterize the material’s state after deformation. These complementary tests will provide valuable microstructural information, enabling the correlation of deformation states with the acquired acoustic images. All the acoustic and microstructural information described above, in conjunction with previous research group data, will be stored in a robust and comprehensive database. This database will serve as the input for a Machine Learning algorithm, which will facilitate the identification of patterns of correspondence between acoustic and microstructural parameters. This approach aims to enable the future prediction, with a high level of probability, of the specific type of plastic deformation mechanism that a material is undergoing based on the acoustic parameter measurements. The successful development of this research proposal would yield several significant outcomes. Firstly, it would enable the early detection of microstructural changes in materials long before fractures occur. Moreover, it would establish a non-intrusive tool for characterizing materials by identifying the underlying mechanisms driving plastic deformation and monitoring the evolution of materials in service over time. Ultimately, this research has the potential to advance our understanding of the plastic behavior of stainless steel and aluminum, opening avenues for improved analysis, design, and performance evaluation of materials in various industrial applications.

Medium manganese steels (MMnS) are currently a subject of active scientific research due to a number of reasons. First, their unique combination of strength and ductility makes them promising candidates for lightweight structural applications in automotive and aerospace industries, where reducing weight without sacrificing mechanical properties is critical. Second, their ability to retain austenite at room temperatures offers advantages in terms of formability and resistance to hydrogen embrittlement, which are significant challenges in steel manufacturing. Third, medium Mn steels have shown potential in enhancing wear and impact resistance, making them suitable for applications in mining, construction, and machinery sectors. Additionally, their corrosion resistance and potential for cost-effective alloying with other elements further expand their utility across various engineering fields. Scientific research on medium Mn steels aims to optimize their microstructure, processing parameters, and alloy compositions to unlock their full potential, thereby contributing to the development of advanced materials that meet the performance requirements of modern industries while promoting sustainability and efficiency in manufacturing processes. The proposed research aims to investigate the stability of austenite in medium manganese steels within ternary Fe-C-Mn and Fe-C-Mn-X systems (X: Al, Si, Cr), focusing on its correlation with processing parameters. The primary objective is to assess the stability of austenite via (i) experimentally determining the martensite start temperature (thermal stability) using dilatometry and thermal analysis techniques, and (ii) to evaluate the fraction of austenite as a function of strain (mechanical stability) under tensile test. These measurements will provide crucial data to understand how variations in processing conditions influence austenite stability. Else, the study will correlate austenite stability with mechanical properties through mechanical tests and in-depth microstructural characterization, aiming to establish predictive models. Additionally, thermodynamic and kinetic calculations will aid in assessing the phase transformation behavior under different thermal histories. The research will extend its scope to evaluate impact and wear properties in relation to austenite stability, crucial for applications in industries requiring high strength and toughness, such as mining and construction. By systematically exploring these relationships, the project seeks to advance the fundamental understanding of medium Mn steels, potentially leading to the development of lightweight, durable materials with enhanced performance characteristics. Ultimately, the findings aim to contribute to the optimization of steel manufacturing processes and the realization of more efficient and reliable engineering solutions in demanding operational environments

Fondecyt de Postdoctorado 2025 Proyecto Nº 3250704, Universidad de Chile y Universidad de O'Higgins - Implementación de la investigación 'Exploración de las bases neuroanatómicas de la alteración del insight en la enfermedad de Alzheimer' como Investigador Postdoctoral

Uso de la química de elementos altamente siderófilos y calcófilos para discriminar rocas asociadas a yacimientos minerales productivos

We propose a three-stage study to explore the roles of BCRNF on NUE, wheat productivity, and nutritional grain quality. In Stage 1, we will assay the effect of BCRNFs on N-dynamics and chemical soil properties through soil incubations performed under controlled conditions for 90 days. We will measure N-losses periodically through volatilization of NH3 and NO2. Additionally, we will quantify potentially mineralizable nitrogen (PMN), changes in the C:N ratio, and changes in pH and soil nutrient content during nine sampling dates. In Stage 2, two independent experiments will be conducted to evaluate the interaction among BCRNFs with soil and its effect on the morphological, physiological, and biochemical plant adaptive strategies related to NUE. In Experiment 1, wheat will be harvested at the pre-anthesis growth stage, and plant growth parameters and N concentration in tissues will be used to determine N uptake efficiency (NUPE). Additionally, it will measure plant adaptative strategies related to N-uptake, such as root architecture, exudation of organic acids by roots, and changes in enzymatic and microbial activities in the soil. In Experiment 2, wheat plants will be harvested at the maturity stage to evaluate the relationship between grain yield and N concentration to determine N utilization efficiency (NUTE). Plant adaptive strategies related to NUTE will also be assessed, including N-translocation and remobilization, CO2 assimilation rate (A), stomal conductance (gs), photosynthesis per unit of N, PNUE. In addition, the leaf response to the fluorescence and stay green trait will also be performed. The amount of nitrogen in grain derived from the fertilizer (Ndff) will be calculated using the δ15N values obtained from grains. In Stage 3, the effect of BCRNFs on wheat productivity and nutritional quality will be evaluated in field conditions. The trials will be conducted over two agricultural seasons, and the impact of BCRNFs on soil and plant samples will be assessed at three different stages: anthesis, soft dough grain, and hard dough grain. During these stages, the chemical properties of the soil, as well as microbial and enzymatic activities, will be evaluated. Photosynthetic parameters such as A, gs, Ci, E, Fo, Fm, and QY will be quantified. The plant height, harvest index, and yield components will be assessed at the end of each growing season. Grain quality indicators like protein content, gluten levels, and sedimentation rate will also be measured. Finally, the amount of nitrogen in grain derived from the fertilizer (Ndff) will be calculated using the δ15N values obtained from grains. This proposal focused on understanding the interconnections among soil, N-fertilizer, and plant physiology, using wheat as a model crop. The primary aim is to boost N management strategies in agriculture, ensuring a balance between productivity and sustainability. The initiative seeks to create a technological solution to enhance NUE, reduce environmental impact, and ensure global food security.

Fondecyt de Postdoctorado 2025 Proyecto Nº 3250704, Universidad de Chile y Universidad de O'Higgins - Implementación de la investigación 'Exploración de las bases neuroanatómicas de la alteración del insight en la enfermedad de Alzheimer' como Investigador Postdoctoral

La violencia ginecológica y obstétrica es una expresión de violencia de género que afecta directamente a la integridad de las mujeres, impactando negativamente en su salud mental, física, sexual y emocional. En el caso de las mujeres con discapacidad su perpetuación se exacerba y complejiza, debido al entramado de violencias (institucional, médica, sexual, económica, de género) a las cuales se han visto sistemáticamente expuestas. Las intervenciones injustificadas, la desinformación, la sobre medicalización y el maltrato, son manifestaciones de violencia ginecológica y obstétrica naturalizadas al interior de la cultura institucional en tanto forman parte fundacional del modelo biomédico, es por ello que la mayoría de las veces no son cuestionadas como actos de violencia o maltrato, sino más bien, se perciben como prácticas de cuidado. A esta problemática, se añade que la representación social e institucional de las mujeres con discapacidad es capacitista y patriarcal, por lo cual es de esperar que en sus trayectorias de vida experimenten algún tipo de vulneración hacia sus procesos sexuales, reproductivos y no reproductivos, sobre todo, en las atenciones de salud. La violencia ginecológica y obstétrica hacia mujeres con discapacidad, ha sido un fenómeno escasamente abordado por la academia y en menor medida aun por instituciones en la materia. Por este motivo, los objetivos generales de esta investigación son: 1)Profundizar en los significados en torno a la vulneración de los procesos sexuales, reproductivos y no reproductivos de las mujeres en situación de discapacidad; 2) Analizar cómo repercute en sus trayectorias de vida la vulneración de sus procesos sexuales, reproductivos y no reproductivos. Los objetivos específicos son: 1)Caracterizar los aspectos que obstaculizan y facilitan el acceso a las atenciones de salud ginecológica y obstétrica de las mujeres en situación de discapacidad; 2)Explorar los mecanismos de vinculación (comunicación, entrega de información, ajustes razonables, trato) del personal de salud hacia las mujeres en situación de discapacidad en las atenciones de salud ginecológica y obstétrica; 3)Ahondar en las prácticas y/o actos identificados por las mujeres en situación de discapacidad como faltas de respeto, malos tratos o prácticas vejatorias percibidas en las atenciones ginecológicas y obstétricas; 4)Indagar en las consecuencias y efectos de la vulneración de los procesos sexuales, reproductivos y no reproductivos de las mujeres en situación de discapacidad y la relación con su autopercepción, autoestima e imagen corporal; 5)Conocer las estrategias de resistencia autogestionadas por las mujeres en situación de discapacidad y organizaciones de mujeres en situación de discapacidad frente a los actos de violencia ginecológica y obstétrica. Se optó por un diseño cualitativo de investigación con elementos de las Epistemologías feministas latinoamericanas, atendiendo a que las dinámicas de poder inciden directamente en la construcción identitaria, corporal y colectiva de las mujeres con discapacidad. Se utilizarán cuatro técnicas de investigación: entrevistas en profundidad (N:20); etnografías (N:4); mapas corporales (N:12); y grupos de discusión (N:5). El perfil de las participantes será: 1)Mujeres que se identifiquen en situación de discapacidad; 2)Que hayan acudido a atenciones de salud ginecológica y/u obstétrica o, en su defecto, que deseen acudir acompañadas a dichas atenciones; 3)Que habiten en las regiones: Ñuble, Bio-Bio, La Araucanía y Los Ríos; 4)Que sean mayores de edad y deseen participar de la investigación. Así mismo, se invitará a organizaciones ampliamente reconocidas por su defensa a los derechos sexuales y reproductivos de mujeres con discapacidad en Chile: CIMUNIDIS, REPRODIS, ODISEX y FEMACU. Los principios éticos adoptados por la Declaración de Singapur guiarán el desarrollo de esta investigación, considerando los criterios de acceso universal acorde a la situación de discapacidad de las participantes y la aprobación del Comité de Ética de la Institución Patrocinante. Para el análisis se utilizará la técnica del análisis temático cualitativo. Los hallazgos contribuirán a: 1)Conocer la realidad de las mujeres con discapacidad respecto a sus procesos sexuales, reproductivos y no reproductivos; 2)Indagar en los aspectos facilitadores y obstaculizadores en las atenciones de salud ginecológica y obstétrica hacia mujeres con discapacidad; 3)Identificar las barreras físicas, actitudinales y culturales a las que se ven expuestas las mujeres con discapacidad en las instituciones de salud; 4)Profundizar en las repercusiones de la violencia ginecológica y obstétrica en las trayectorias de vida de las mujeres con discapacidad; 5)Trabajar articuladamente con organizaciones de mujeres con discapacidad; 6)Aportar en los diálogos colectivos con especial incidencia en la política territorial y nacional; 7)Consideración de protocolos de buen trato en la atención sanitaria; 8)Revisión de programas regionales enfocados en la salud sexual y reproductiva de mujeres con discapacidad; 9)Presentación en jornadas académicas nacionales e internacionales de los principales hallazgos; 10)Elaboración de producción científica en colaboración con las participantes y organizaciones como expertas por experiencia.

El proyecto constituye una investigación cualitativa con enfoque territorial, transdisciplinario y de género que analiza las experiencias parto y crianza de mujeres migrantes que han dado a luz y residen en la Región de O'Higgins. Explora sus experiencias de maternidades con el propósito de rescatar los procesos que atraviesan las mujeres en movilidad, las resistencias y las luchas que despliegan en el ámbito sanitario. Bajo la teoría de la autonomía de las migraciones y de la interseccionalidad, esta investigación recopila y rescata los procesos vivenciados en sus trayectorias, examinando sus experiencias de gestación, parto y crianzas, con el propósito de dar cuenta de sus percepciones, así como de las estrategias y reivindicaciones que despliegan en la salud pública en esta región, posibilitando una aproximación comprensiva de las maternidades y de las múltiples formas de opresión y resistencia de las mujeres migrantes. Este proyecto aporta una mirada que da espacio a aquellas mujeres migrantes cuyas experiencias suelen ser invisibilizadas por un sistema de salud que en ocasiones naturaliza el silenciamiento, regulando sus vivencias reproductivas acorde al modelo biomédico. En ese marco, es una investigación que, desde una perspectiva feminista situada e interseccional, invita a cuestionar el dispositivo de salud que en ciertas situaciones impone un tutelaje sobre el cuerpo y comportamiento de las personas gestantes, desconociendo las múltiples formas de ejercer la maternidad y de configurar los vínculos maternofiliales. La investigación al hacer visibles estas vivencias y reconocer los sentires y saberes de las migrantes, propone una visión que rescata la diversidad de las experiencias maternas, subrayando las tensiones y contradicciones que se enfrentan en el entorno sanitario. En este sentido, el proyecto aporta al conocimiento analítico de las maternidades, los modos de ejercer las crianzas y los cuidados, proveyendo un examen desde las experiencias de las mujeres en movilidad. En consecuencia, es una indagación que, centrándose en las narrativas de las protagonistas, insta a la politización de las maternidades, valorizando las estrategias que las migrantes gestantes desarrollan en el espacio sanitario. Objetivos: Este proyecto tiene por finalidad: analizar en profundidad las experiencias de maternidades y crianzas de mujeres migrantes en el sistema de salud público de la Región de O’Higgins, recopilando sus voces y vivencias, reconociendo sus procesos y capacidad de agencia. Los objetivos específicos son: 1) identificar las percepciones y experiencias de las mujeres migrantes en relación con el acceso y la calidad de los servicios de salud en la Región de O’Higgins; 2) indagar en las estrategias de resistencia y resiliencia que las migrantes despliegan frente a las barreras en este ámbito y ejercer sus prácticas de cuidado; y, 3) proponer directrices para diseñar políticas públicas que integren un enfoque interseccional, feminista y de derechos humanos, con el fin de adecuar la atención en salud a las necesidades de las mujeres migrantes.