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Perception of procedural competencies for undergraduate medical trainees: a multilevel diagnostic study for curricular intervention
No full textPurpose: Medical education constantly adapts to evolving competencies required by the healthcare system, yet a gap persists in aligning perceived and actual competency requirements. Existing literature suggests that simulation-based medical education could bridge this gap by enhancing skill acquisition and boosting confidence among medical students. This study aims to evaluate the perceptions of medical competencies across different stakeholders of the medical education community in comparison to the standards set by the Association of Chilean Medical Schools (ASOFAMECH).
Methods: A cross-sectional study was conducted with participants from a Chilean School of Medicine, including students, interns, graduates, and faculty. Through a dynamic cross-sectional survey, we assessed perceptions of 35 medical competencies, categorized into nursing skills (NS), emergency skills (ES), and gynecology and pediatrics skills (GPS), comparing them to the national standards defined by ASOFAMECH. Non-parametric statistics were employed for data analysis.
Results: Out of 287 collected surveys, 244 were fully completed and included in the analysis. Confirmatory factor analysis validated the clustering of skills. Results revealed significant discrepancies between the participants’ perceived competencies and national standards, with a general tendency to overestimate the requirements. However, perception of skills taught through standardized simulation training (SST) did not significantly differ from non-SST skills.
Conclusions: We conducted the first comprehensive diagnostic evaluation of competency perceptions and their comparisons with national standards, providing detailed insights into medical training within a specific medical-academic community. This study marks a significant milestone in assessing medical skill development at the undergraduate level in Chile, utilizing validated groups for analysis and a replicable approach to assess both the ASOFAMECH framework and other guidelines. Our findings offer valuable insights for improving curriculum development and assessment, addressing perceived deficiencies and strengths among students, interns, clinicians, and faculty
CPAP improves regional lung strain rate and diaphragm velocity of relaxation in experimental self-inflicted lung injury
No full textBackground Strenuous respiratory effort has been proposed as a second hit in severe acute lung injury (ALI), introducing the concept of “patient self-inflicted lung injury” (P-SILI). In an experimental setting, noninvasive continuous positive airway pressure (CPAP) attenuates lung and diaphragmatic injury, but the underlying mechanisms remains elusive. Here we investigate the effects of noninvasive CPAP on global and regional lung strain and diaphragm velocity of contraction and relaxation in an experimental P-SILI model. Methods Lung injury was induced in Sprague Dawley rats through surfactant depletion followed by either three hours of standard oxygen therapy (Control group) or CPAP support (CPAP group). Subjects were assessed through inspiratory and expiratory muscle activation. Regional lung and diaphragmatic deformation amplitude (strain) and the rate of change (strain rate) maps were developed using a micro-computed tomography (µCT) scan. Morphometric tissue assessment was carried out to study biological damage. Results Compared with the Control group, the CPAP group resulted in: (1) higher SpO2 and lower respiratory rate, nasal flaring, inspiratory and expiratory muscle activation, and minute ventilation at the end of the study; (2) lower global and regional tidal ventilation at the beginning of the study; (3) lower regional inspiratory and expiratory lung strain rate over time; and (4) higher muscle area in the diaphragm morphometric analysis. Furthermore, intragroup analysis showed that only the CPAP group reduced the inspiratory and expiratory muscle activation, the global and regional expiratory lung strain rate and the regional velocity of relaxation of the diaphragm over time. Conclusions Standard oxygen therapy resulted in worse patterns of lung strain rate and diaphragm velocity of relaxation, consistent with P-SILI and load-induced diaphragm injury. CPAP resulted in improved lung function, decreased lung strain rate, and diaphragmatic relaxation velocity throughout the respiratory cycle. We conclude that CPAP promotes biomechanical protection in injured lungs and diaphragm, more noticeably during the expiratory phase
1er Escáner legislativo SECOS. Oportunidades para aportar con evidencia y conocimiento de investigación en la discusión legislativa
No full textEste primer escáner legislativo es parte del Observatorio de Políticas Públicas del Instituto Milenio en Socio-Ecología Costera (SECOS) y fue desarrollado por la Unidad de Ciencia y Políticas Públicas con el objetivo de visibilizar la ventana de oportunidad para informar con evidencia y conocimiento de investigación la discusión legislativa en los temas relacionados con los sistemas socio-ecológicos (SES) de Pesca artesanal, Acuicultura de moluscos y Desarrollo Costero de relevancia para SECOS.Nuestro objetivo es contribuir a visibilizar los proyectos de ley (PDL) que están siendo activamente discutidos en el Congreso Nacional identificando los temas en los que académicos, académicas e investigadores pueden realizar un aporte significativo.Esta primera entrega considera la actividad legislativa de proyectos presentados durante el último semestre del año en curso, periodo en el cual hemos identificado un total de 8 PDL, 4 relacionados con el SES Pesca Artesanal y 4 al SES Desarrollo costero. Además, de estos 8, 6 corresponden a Institucionalidad y regulación, 1 a Gestión y manejo de recursos hidrobiológicos y 1 a Desarrollo socioeconómico.Agradezco el apoyo de SECOS para el desarrollo de este trabajo y los y las invito a revisar la información contenida en este escáner como insumo para identificar áreas potenciales de contribución y participación como ciudadanos y productores de conocimiento. Francisca Reyes.ANID-Programa Iniciativa Científica Milenio; Folio: ICN2019_01
Dynamic weed control using selective laser application with object tracking and target scheduling
No full textSelective laser application for weed control is emerging as one of the most sustainable practices for various crops. The system targets weeds using a laser beam with specific time and intensity settings to eliminate undesired plants through thermal damage. However, this process — commonly known as static weed laser treatment — reduces machinery efficiency, as the platform must remain stationary until all visible weeds are treated. To address this limitation, the current work proposes a dynamic laser weeding approach that predicts weed positions while the platform is in motion, thereby improving operational efficiency. Several deep learning architectures (e.g., YOLO series for weed detection and DeepSORT for weed tracking) are evaluated to identify the most effective models for detecting and tracking multiple weeds in RGB images. In addition, a time-constrained scheduling strategy is implemented to determine the order in which weeds are treated, minimizing the number of missed targets. We find that receding horizon control offers the best performance, particularly under strict time and energy constraints. Field deployment results show that YOLOv7 achieves the highest precision, recall, and mean Average Precision (mAP) for weed detection. The dynamic laser weeding system significantly outperforms the static counterpart, enabling up to 2.8 times faster movement while successfully treating 90% of detected weeds. This work presents a proof of concept for dynamic weeding, laying the foundation for future developments in intelligent, autonomous crop protection systems
Mathematical analysis and applications of neural networks, with applications to image reconstruction
No full textTesis (Phd in Mathematics)--Pontificia Universidad Católica de Chile, 2025This thesis explores two fundamental aspects of neural networks: their frequency learning behavior and their application to quantitative Magnetic Resonance Imaging (MRI) reconstruction. The first part investigates the phenomenon of frequency bias, the empirical observation that neural networks tend to learn low-frequency components of a target function more rapidly than high-frequency ones. To provide a rigorous understanding of this behavior, we develop a theoretical framework based on Fourier analysis. Specifically, we derive a partial differential equation that governs the evolution of the error spectrum during training in the Neural Tangent Kernel regime, focusing on two-layer neural networks. Our analysis centers on Fourier Feature networks, a class of architectures where the first layer applies sine and cosine activations using pre-defined frequency distributions. We demonstrate that the network's initialization, particularly the initial density distribution of first-layer weights, plays a crucial role in shaping the frequency learning dynamics. This insight provides a principled way to control or even eliminate frequency bias during training. Theoretical predictions are validated through numerical experiments, which further illustrate the impact of initialization on the inductive biases of neural networks.The second part of the thesis applies neural network techniques to the reconstruction of quantitative MRI data. Quantitative MRI enables the estimation of tissue-specific parameters (e.g., T1, T2, and T2*) that are vital for clinical diagnosis and disease monitoring. However, these methods typically require long acquisition times, which are often mitigated through aggressive undersampling of k-space data. Undersampling, in turn, introduces reconstruction artifacts that must be addressed through regularization. To this end, we propose CConnect, a novel iterative reconstruction method that incorporates convolutional neural networks into the regularization term. CConnect connects multiple CNNs through a shared latent space, allowing the model to capture common structures across different image contrasts. This design enables the effective suppression of aliasing artifacts and improves image quality, even in highly undersampled scenarios. We evaluate CConnect on in-vivo brain T2*-weighted MRI data, demonstrating its superiority over classical low-rank and total variation methods, as well as standard deep learning baselines.ANI
Political science and Gender: from Historical Divorce to Constructive dialogue
No full textEste artículo examina la relación entre la ciencia política y los estudios de género, destacando una evolución desde el distanciamiento inicial hacia una creciente integración. Aunque persisten resistencias dentro de la disciplina, las perspectivas feministas han generado aportes clave en temas como representación política, análisis institucional y políticas públicas. A su vez, los estudios de género han ampliado los objetos, metodologías y enfoques de la ciencia política. A partir de una revisión sistemática de la literatura y el análisis de casos paradigmáticos en América Latina, se identifican siete áreas de diálogo fructífero que han contribuido a transformaciones políticas concretas. Se concluye que, para una integración más plena, se requiere mayor apertura disciplinaria y un compromiso con enfoques verdaderamente interdisciplinarios.This article examines the relationship between political science and gender studies, highlighting a shift from an initial disconnect toward increasing integration. Although resistance within the discipline persists, feminist perspectives have made key contributions to issues such as political representation, institutional analysis, and public policy. In turn, gender studies have broadened political science’s objects of study, methodologies, and approaches. Drawing on a systematic literature review and an analysis of paradigmatic cases in Latin America, the article identifies seven areas of fruitful dialogue that have contributed to concrete political transformations. It concludes that achieving fuller integration requires greater disciplinary openness and a commitment to genuinely interdisciplinary approaches
"The Earth Trembled and the Rocks Broke" (Mt 27,51). An Anthropo-cosmic Reading of the Easter of Jesus as a Crack, Crisis and Break
No full textEl artículo tiene como propósito reconocer cómo el acontecimiento de la Pascua de Jesús, en cuanto expresión de una grieta, de una fisura, de un quiebre o una crisis permite el surgimiento de una narrativa, de una escritura o de un discurso que, tomando en consideración dicha crisis, abre otro espacio del decir. Para lograr el mencionado propósito se ofrecen una serie de reflexiones que ponen a la teología en diálogo con diversas ciencias humanas como la literatura, el psicoanálisis y la antropología, en cuanto disciplinas que modulan la categoría y experiencia de lo agrietado. En definitiva, se trata de mostrar que la grieta y la crisis son experiencias que animan la reflexión teológica porque su constitutivo, la resurrección de Jesús, es en sí misma una experiencia de la grieta
Measurements of W+W− production cross-sections in pp collisions at √s = 13 TeV with the ATLAS detector
No full textMeasurements of W+W− → e±νμ∓ν production cross-sections are presented, providing a test of the predictions of perturbative quantum chromodynamics and the electroweak theory. The measurements are based on data from pp collisions at s = 13 TeV recorded by the ATLAS detector at the Large Hadron Collider in 2015–2018, corresponding to an integrated luminosity of 140 fb−1. The number of events due to top-quark pair production, the largest background, is reduced by rejecting events containing jets with b-hadron decays. An improved methodology for estimating the remaining top-quark background enables a precise measurement of W+W− cross-sections with no additional requirements on jets. The fiducial W+W− cross-section is determined in a maximum-likelihood fit with an uncertainty of 3.1%. The measurement is extrapolated to the full phase space, resulting in a total W+W− cross-section of 127 ± 4 pb. Differential cross-sections are measured as a function of twelve observables that comprehensively describe the kinematics of W+W− events. The measurements are compared with state-of-the-art theory calculations and excellent agreement with predictions is observed. A charge asymmetry in the lepton rapidity is observed as a function of the dilepton invariant mass, in agreement with the Standard Model expectation. A CP-odd observable is measured to be consistent with no CP violation. Limits on Standard Model effective field theory Wilson coefficients in the Warsaw basis are obtained from the differential cross-sections
El Paisaje Cultural del Santuario de la Naturaleza Humedales del Río Maullín: hacia una guía metodológica para su identificación y catalogación desde una perspectiva hidrocultural
No full textTesis (Magíster en Patrimonio Cultural)--Pontificia Universidad Católica de Chile, 2025Este proyecto aborda el Santuario de la Naturaleza Humedales del Río Maullín desde el enfoque de los paisajes culturales, proponiendo una guía metodológica orientada a la identificación e inventariado de sus elementos patrimoniales desde una perspectiva hidrocultural. En un contexto de acelerada fragmentación territorial, producto de la proliferación de parcelas de agrado y la mercantilización del suelo, se analiza cómo estas transformaciones afectan las formas ancestrales de habitar, las prácticas artesanales y los equilibrios ecológicos del sistema de humedales, revelando las limitaciones de los marcos oficiales de conservación centrados en criterios cargadamente bio-ecológicos. El estudio se articula a partir de herramientas metodológicas provenientes de los estudios críticos del patrimonio, la ecología política y las posthumanidades, integrando análisis de archivo, observación participante y etnografía multiespecie. Desde una mirada relacional del paisaje, se interpreta el territorio del Río Maullín como una red activa de significados, memorias y agencias, donde confluyen actor es humanos y otros-que-humanos en la creación de valor patrimonial.El proyecto culmina con el diseño de una guía metodológica destinada a facilitar procesos participativos de identificación y puesta en valor del paisaje cultural del sistema de humedales del Río Maullín. Esta herramienta propone criterios y actividades que reconocen la dimensión hidrocultural del territorio, integrando saberes comunitarios y cosmologías indígenas como parte fundamental del inventario patrimonial.Fondecy