Poster Sessions 2025

Poster Sessions 2025

101
Robustness of Deep Learning-Based Ultrasound Beamformers to Adversarial and Realistic Distortions
Itamar Salazar
Itamar Salazar
Adversarial perturbations are specially crafted noise patterns designed to degrade the performance of machine learning models. In this study, we investigate their impact on deep learning-based ultrasound beamformers. We evaluate three previously reported end-to-end DNN-based beamformers trained on simulated ultrasound data. These models are assessed under both adversarial perturbations and realistic distortions. Our results reveal a correlation between the distortions caused by adversarial perturbations and those observed in realistic scenarios— a relationship not evident with Gaussian or uniform noise. These findings provide insights into the robustness and generalization of DNN-based beamformers, particularly in scenarios where simulated data is used to train deep learning models, as is common in medical imaging applications.
Adversarial perturbations, medical imaging, generalization
102
How Tiny Titans Excel in Generative Tasks in Portuguese
Gabriel Assis, Aline Paes
Gabriel Assis
The development of Large Language Models (LLMs) has transformed natural language processing, yet their reliance on extensive computational resources poses challenges for regions with limited infrastructure, such as Brazil. This work evaluates language models, including general-purpose models and Portuguese-specialized alternatives, across question answering, text simplification, and summarization tasks in Portuguese. The assessment considers both generative quality and computational efficiency, addressing sustainability concerns. Results highlight the importance of adapting models to linguistic and cultural specificities. By analyzing performance across diverse tasks and metrics, this work aims to contribute to democratizing LLM development and application in low-resource settings, fostering research aligned with regional realities and sustainability goals.
Small language models, Brazilian Portuguese, Natural Language Generation
103
Language Variety Analysis with BERT: Exploring Portuguese in Brazil, Portugal and Mozambique
Annie Amorim, Gabriel Assis, Laura Ribeiro, Daniel de Oliveira, Aline Paes
Annie Amorim
Social network users commonly propose new expressions to make communication faster, more fluid, and more original. Moreover, although they follow a specific idiom, the employed language is also mixed-coded, making even the same idiom go beyond the usual variations. This way, texts in Portuguese from different regions that already have linguistic, syntactic, lexical, and orthographic differences go to a new level when written in social media posts. This work proposes relying on Portuguese language models to analyze the variations of Portuguese in social media posts in Brazil, Portugal, and Mozambique.
Model Merging, Hate Speech, Latam Languages
104
Teaching critical AI at school
Julián Dabbah, Marcos J. Gómez
Marcos J. Gómez
This poster presents a curriculum proposal and didactic materials designed to promote a critical approach to teaching AI in schools. The AI Curriculum proposal is part of Argentina’s broader initiative to include Computer Science in compulsory education. Developed by the Program.AR Initiative of the Sadosky Foundation and researchers from various universities, this proposal defines key AI and CS concepts necessary for full citizenship in a technology-driven society. It outlines a progressive learning path from early childhood to high school, emphasizing data analysis, AI applications, and ethical considerations. Additionally, we share findings from the implementation of an AI workshop for high school students and teacher training programs. The workshop integrates technical and ethical perspectives, focusing on biases in AI models. Participants engage in hands-on activities, experiencing how decisions in AI development introduce biases. Pre and post-test analysis revealed a significant shift in participants’ perceptions, reducing beliefs in AI’s neutrality and superiority over human decision-making. The workshop was perceived as engaging and practical, leading to the creation of educational materials for broader classroom implementation. This work contributes to ongoing discussions on AI education, offering tools for critically analyzing and understanding the role of AI in contemporary society.
AI Curriculum, AI literacy, schools
105
Legal Information Retrieval
Leon Hecht, Helena Gomez Adorno
Leon Hecht
Not available yet
Legal, information, retrieval
106
Causal Inference and Machine Learning in HealthCare
Anisio Lacerda
Anisio Lacerda
The intersection of **Machine Learning (ML) and Causal Inference** holds great promise for advancing healthcare by enabling robust decision-making and personalized treatment strategies. Our research group focuses on **developing and applying causal ML methodologies** to tackle key challenges in **mental health, ECG analysis, and diabetic retinopathy diagnosis**. In mental health, we leverage **interventional modeling** to assess the impact of treatment strategies on patient outcomes, aiding in the design of personalized interventions. For ECG analysis, we integrate ML with **counterfactual prediction frameworks** to estimate the potential effects of different clinical interventions on cardiac health, addressing treatment-effect heterogeneity. In the context of diabetic retinopathy diagnosis, we employ **causal ML techniques** to mitigate confounding biases in predictive models, improving the reliability of automated screening tools. By bridging **causal inference and ML**, our work aims to move beyond correlation-based approaches, enabling more **trustworthy, interpretable, and actionable** healthcare predictions. Our research contributes to the growing field of **causal ML for healthcare**, fostering collaboration between machine learning practitioners and medical experts to improve patient outcomes.
Causal inference, Machine Learning, Healthcare applications
107
Information extraction from Electronic Health Records written in Spanish for epidemic intelligence
Javier Petri, Pilar Bárcena Barbeira, Viviana Cotik
Viviana Cotik
Automatic symptom detection from electronic health records is a valuable source for event-based surveillance systems. In this study, we develop tools to automatically detect symptoms associated with febrile illnesses in electronic health records written in Spanish. Therefore, we use a custom corpus, comprising 6228 expertly labeled and approximately 1 million unlabeled health reports. Our approach involved fine-tuning state-of-the-art named entity recognition models, including BiLSTM-CRF and transformer-based models like RoBERTa. We focused on domain-adaptive and task-adaptive models to enhance performance: the former were pre-trained on biomedical corpora, while the latter were further pre-trained on our unlabeled health reports. Despite computational constraints, our models demonstrated promising results, with RoBERTa-Clinico, a task-adaptive transformer model pre-trained in our unlabeled corpus, showing the best micro recall performance (79.30), and 70.83 micro F1 score, which are comparable to results in similar studies. In this way, we contribute to the limited body of work in BioNLP in Spanish.
Named entity recognition, BioNLP, Spanish electronic health records
108
Analysis of Antisemitic Hate Speech in Digital Newspaper Comments in Latin America
Florencia Altschuler, Viviana Cotik
Florencia Altschuler
Online platforms facilitate the exchange of opinions but also enable the spread of hate speech, including antisemitism. Despite its growing presence in digital news comments, most research on hate speech detection focuses on English, leaving Spanish-language content underexplored.This study investigates antisemitic discourse in digital newspaper comments from Argentina, Chile, Colombia, Costa Rica, Panama, and Uruguay. It identifies temporal and spatial patterns and examines distinctive linguistic features of antisemitic comments. A manually annotated corpus of 13,511 comments from 2,834 news articles mentioning "Israel" since February 2021 was compiled. The study aims to present and describe this dataset while analyzing its lexical characteristics.Unigram analysis identifies characteristic terms in antisemitic versus non-antisemitic comments. Additionally, the study develops automatic detection tools using large language models, such as GPT-4 and Llama 3.2 3B, implementing few-shot and zero-shot learning strategies through prompt engineering. Model performance is evaluated with metrics that account for class imbalance, including the F1 score.This research advances antisemitic discourse detection in Spanish and contributes to the development of essential tools to address the growing phenomenon of online hate speech targeting cultural and religious minorities.
Antisemitism, Hate Speech Detection, Large Language Models
109
UruDendro: Application of Image Processing and Artificial Intelligence Techniques for the Automatic Dendrometry of Native and Commercial Wood Species
Henry Marichal, Veronica Casaravilla, Karolain Mello, Chistine Lucas, Diego Passarella, Ludmila Profumo, Gregory Randall
Henry Marichal
This work presents an automatic Tree Ring Delineation method for complete cross-sections of conifer tree images (CS-TRD) and its extension to angiosperms and shrubs (DeepCS-TRD). The method detects, processes, and connects edges corresponding to tree growth rings. It relies on edge detection parameters and the precise location of the pith—the soft central region of the wood slice, which is concentric to all rings but not always positioned at the geometric center.The pith location is estimated using an automated method based on the concentric structure of tree rings (APD). This approach leverages local ring orientations, estimated via the 2D structure tensor, to identify the optimal pith candidate through a dedicated cost function.DeepCS-TRD enhances CS-TRD by replacing the edge detection step with a deep-learning-based segmentation model (U-Net), enabling its application across diverse imaging modalities—including microscopy, scanner, and smartphone images—and various species.A graphical user interface was developed to compute key wood cross-section metrics such as growth area and perimeter. Users can manually refine ring detections through an intuitive interface.
Tree-Rings, Dendrometry, wood cross-section
110
Temporal Explainability in Audio Models
Cecilia Micaela Bolaños, Leonardo Pepino, Martin Meza, Pablo Riera, Luciana Ferrer
Cecilia Bolaños
Understanding how audio models make predictions is crucial for their interpretability and trustworthiness. In this work, we explore temporal explainability in audio models, aiming to generate explanations that evolve over time and align with the model’s decision-making process. We focus on developing robust evaluation methods to assess the quality of these explanations, ensuring they provide meaningful insights. Additionally, we leverage these explanations to uncover biases and hidden correlations in audio representations
explainability; audo; spurious correlation
111
Differentially Private Optimization with Sparse Gradients
Badih Ghazi, Cristóbal Guzmán, Pritish Kamath, Ravi Kumar, Pasin Manurangsi
Cristóbal Guzmán
Motivated by applications of large embedding models, we study differentially private (DP) optimization problems under sparsity of individual gradients. We start with new near-optimal bounds for the classic mean estimation problem but with sparse data, improving upon existing algorithms particularly for the high-dimensional regime. Building on this, we obtain pure- and approximate-DP algorithms with almost optimal rates for stochastic convex optimization with sparse gradients; the former represents the first nearly dimension-independent rates for this problem. Finally, we study the approximation of stationary points for the empirical loss in approximate-DP optimization and obtain rates that depend on sparsity instead of dimension, modulo polylogarithmic factors.
Differential privacy, Convex Optimization, Learning Theory
112
Identificación de textos relacionados al cambio climático y sustentabilidad utilizando modelos de lenguaje preentrenados en español
Gerardo Huerta Robles , Gabriela Zuñiga Rojas
Gabriela Zuñiga Rojas
Este estudio presenta un método para identificar textos relacionados con el cambio climático y la sustentabilidad en español mediante modelos de lenguaje preentrenados. El objetivo es desarrollar una herramienta que identifique, entre distintos textos, aquellos que aborden temas como el cambio climático y sus efectos. Se creó un dataset etiquetado con textos en español, se entrenó el modelo con estos datos y se evaluó utilizando un conjunto de validación, logrando una precisión de 0.916. F1 Score de 0.95 y Recall de 0.99. Los resultados muestran la efectividad del enfoque propuesto para identificar textos relevantes sobre el cambio climático en español. Este modelo puede ser una herramienta útil para crear y enriquecer repositorios sobre el tema, contribuyendo a una mayor conciencia y comprensión sobre el cambio climático y sus implicaciones.
Cambio Climático, identificación de texto, modelos de IA pre-entrenados
113
Application of GenAI Tools for Data Governance Tasks
Patricia Chandía
Patricia Chandía
This study examines the implementation of generative artificial intelligence (GenAI) to optimize data governance in a Chilean social security entity. Facing current challenges in personal data protection and regulatory compliance, a solution based on fine-tuning and prompt engineering was developed for Google's Gemini foundation model, which automates key metadata management processes. The system implements a pipeline of five main tasks: generation of field and table descriptions, identification of personal and sensitive data, and classification according to business domains. The evaluation through quantitative and qualitative metrics demonstrated high precision in sensitive data identification and significant improvements in operational efficiency. Despite identified technical and organizational limitations, the results validate the feasibility of digital transformation in data governance through GenAI, establishing a precedent for its application in social security organizations.
data governance, generative artificial intelligence, personally identifiable information, data ethics
114
KRASS: Knowledge Retrieval and Analysis for Scientific Support
Jorge Saavedra-Bastidas, Manuel Pérez-Carrasco, Nicolás Núñez
Jorge Saavedra
The landscape of the natural sciences, particularly within computer science, is evolving at an increasingly rapid pace. Scholars face growing challenges in analyzing and synthesizing emerging research before it becomes outdated. Large Language Models (LLMs) currently demonstrate superhuman capabilities in processing and analyzing information at remarkable speeds; however, they are susceptible to generating hallucinations when queried for specific information beyond the scope of their training corpus. In this context, we introduce Knowledge Retrieval and Analysis for Scientific Support (KRASS), an open-source algorithm designed to facilitate literature reviews and state of the art follow-up on a given subject. KRASS leverages Large Language Models within a Conditional Retrieval-Augmented Generation (CRAG) framework to evaluate, retrieve, refine, and analyze academic literature in response to specific expert queries. We evaluated the performance of our algorithm across various Large Language Models and academic topics, and assessed its ability to retrieve sources and generate summaries from the selected literature in response to user queries.
Large Language Models, Retrieval Augmented Generation, Agents
115
Temporal Correspondence Between Human Brain and Vision Transformers in Rapid Stimuli Tasks
Marraffini Giovanni Franco Gabriel, Lützow holm Eric, Tagliazucchi Enzo
Giovanni Marraffini
Visual processing in the human cerebral cortex is hierarchical and highly parallelized. Similarly, in the deep learning architecture known as vision transformers, data is processed iteratively through attention operations, which allow for the parallel evaluation of the importance of certain aspects of the image in the context of the rest of the image. In both the human brain and transformers, the attention mechanism selects parts of the input that are more relevant to the task at hand, enabling the model to prioritize and weigh this information during processing. In this work, we investigate the temporal correspondence between both systems, based on the hypothesis that each successive layer of the transformer will be correlated with temporally ordered components of the EEG response in an object recognition task. First, we analyze the representational similarity between the two systems, then we investigate predicting brain activations based on neural network activations, and finally, we use a state-of-the-art metric to make comparisons between neural network representations. We find that the early layers of the network are mostly aligned with the early stages of electrophysiological signals, while the advanced layers correspond to later stages.
Visual processing, EEG, vision transformers
116
A Software Framework for Multi-Objective Optimization in Machine Learning
Aline C C S Azevedo
Aline Azevedo
Handling conflicting objective functions in machine learning, such as those related to fairness, class imbalance, reinforcement learning, multi-task learning, or multi-class classification, is not an easy task. Using a single loss function, it is hard to properly optimize these conflicting objectives of reducing false positive and false negative rates simultaneously. For that reason, multi-objective optimization methods can be very advantageous as they minimize incorrect answers by tuning the machine to automatically promote lower false positive or false negative rates with different trade-offs, resulting in a set of efficient classifiers.While there are different methods to deal with this challenge, a comprehensive framework for multi-objective optimization in machine learning contexts remains lacking. This research aims to fill this gap by formalizing and implementing such a framework, along with exploring and contextualizing multi-objective optimization methods and their application in machine learning, especially in fair models. Additionally, the goal is to offer a user-friendly implementation through a Python package that can be integrated with other machine learning libraries, such as Scikit-learn, TensorFlow, and PyTorch, to facilitate its use in machine learning problems.
Machine Learning, Multi-Objective Optimization, Ethics
117
Automatic detection of sexual and reproductive health care consults from people with disabilities
Mariela Rajngewerc, Sabrina López,Laura Alonso Alemany, Marina Elichir, Cecilia Palermo, Milagro Teruel, María Victoria Tiseyra, Verónica Xhardez
Mariela Rajngewerc
This work studies the feasibility of automatically detecting consultations on sexual and reproductive health (SSH) in the electronic health records (EHR) of people with disabilities (PWD) with machine learning models. This could be an input to improve access to SSH for this population through the adaptation of future consultations, obtaining better statistics, and supporting health management planning.An interdisciplinary team worked on: the construction of operational definitions of SSH and PWD consultation, the identification of entities in free and structured text of the EHR, the development of a manually annotated data set for training the models, obtaining the classification models for automatic detection and their evaluation with equity metrics.First, a classifier for identifying SSH queries and another for identifying if the query corresponds to PWD where created. Then, the concatenation of these classifiers was considered as the final model.As a result, the accuracy of these models is ~80% for each of these categories separately. However, for the simultaneous classification of SSH and PWD, the accuracy is 62%, which is much higher than that based on regular expressions and logical rules (with an accuracy of 19%). This allows us to guide future work in improving the proposed models.
Electronic Health Records, Sexual and Reproductive Health, People with Disabilities
118
Development of an AI Model for Predicting River Flow Fluctuations to Enhance Hydro-Climatic Risk Management
Boris Luis Ramos, Lina Montoya, Carlos Lincango, Ángelo Yagual.
Boris Luis Ramos Luis
This study is focused on developing an artificial intelligence (AI) model that predicts increases in river flow fluctuations to improve hydro-climatic risk management, thereby mitigating economic losses and saving lives. The research utilizes 26,788 hydrometeorological data points from Colombia (1950–2024) along with climate indices provided by the National Oceanic and Atmospheric Administration (NOAA). The key inputs for the model are the river flow values and corresponding dates, which are merged with the time series of the climatical indices obtaining a multivariate time series.Initially, the model forecasts a single value; however, it is designed to generate multi-step predictions using neural networks. A Long Short-Term Memory (LSTM) model is proposed, leveraging its capability to handle long-term dependencies in multivariate time series. The model is evaluated primarily using the Root Mean Squared Error (RMSE), and its precision and robustness are further validated with complementary metrics: MSE, MAE and RMSLE. Alternative approaches such as Recurrent Neural Networks (RNN) and statistical models (ARIMA, SARIMA) were initially considered, but these exhibit certain limitations. The state-of-the-art review highlights previous models—like cascade feedforward networks and ARIMA—that face constraints in terms of temporal dynamics and variable handling.
LSTM, RMSE, Hydrometeorology.
119
Global-MuMu Exams: In-language Exams for Massively Multilingual Vision Evaluation
Israfel Salazar*, Manuel Fernández Burda*, Shayekh Bin Islam*, Arshia Soltani Moakhar*, Shivalika Singh*, Angelika Romanou, Danylo Boiko, Fabian Farestam, Dipika Khullar, Mike Zhang, Dominik Krzemiński, Jekaterina Novikova, Luísa Shimabucoro, Joseph Marvin Imperial, Rishabh Maheshwary, Sharad Duwal, Alfonso Amayuelas, Swati Rajwal, Jebish Purbey, Ahmed Ruby, Nicholas Popovič, Azmine Toushik Wasi,Ram Mohan Rao Kadiyala, Olga Tsymboi, Maksim Kostritsya, Bardia Soltani Moakhar, Gabriel da Costa Merlin, Otávio Ferracioli Coletti, Maral Jabbari Shiviari, MohammadAmin farahani fard, Silvia Fernandez, María Grandury, Dmitry Abulkhanov, Drishti Sharma, Marek Suppa, Andre Guarnier De Mitri, Leticia Bossatto Marchezi, Johan Orbando, Nazar Kohut, Diyi Yang, Desmond Elliot**, Enzo Ferrante**, Sara Hooker**, Marzieh Fadaee**
Manuel Fernández Burda
The evaluation of vision large language models (VLLMs) has mainly relied on English-language benchmarks, leaving significant gaps in both multilingual and multicultural coverage. While multilingual benchmarks have expanded, many rely on translations of English datasets, failing to capture cultural nuances. In this work, we propose Global Multimodal and Multilingual Exams (Global MuMu Exams) as the most comprehensive exams benchmark for multilingual evaluation to-date of vision models. Global MuMu Exams is a large-scale, in-language multimodal benchmark designed to evaluate MLLMs across diverse languages and visual inputs. We cover 18 languages, 14 different subjects, and a total of 20,911 multiple-choice questions, of which 55% require image understanding. Built through a direct collaboration with a diverse group of researchers worldwide, Global MuMu Exams ensures linguistic and cultural authenticity. We evaluate top performing multilingual vision-language models, and find that they perform poorly on low-resource languages and in complex multimodal scenarios. Our results highlight the need for progress on culturally inclusive multimodal evaluation frameworks.
Large Language Model Evaluation, Multimodality, Multiligual
120
Breast Tumor Detection for MRI with Contrast
Marcelo Carneiro, Otávio Moreira, Rodrigo Schuller
Marcelo Carneiro
We'll present partial results of our ongoing research (in partnership with DASA) in tumor detection and classification in breast MRI's. Mainly focusing on the results obtained using CNN's and the impacts of data augmentation. Although our objectives are detection and classification, we'll present only detection, since classification is still in early development.
Segmentation, cancer, CNN
121
Towards Audio-Based Harmonic Analysis: Initial Results with DeepToneNets
Thiago Poppe, Luisa Lopes, Fernando Tonucci, Flavio Figueiredo
Luisa Carvalhaes
Functional Harmony, or Roman Numeral Analysis, studies the roles of chords within a musical progression, categorizing them into functions like tonic (stability), subdominant (instability and change), and dominant (dissonance and transition). This task is challenging because a chord's function depends on the overall musical context, and the same chord can have different roles even within the same piece. While deep learning has advanced symbolic music analysis, directly analyzing functional harmony from audio signals remains a complex and underexplored problem. We propose DeepToneNets (DTNs), a novel deep-learning approach that combines neural networks for harmonic and bass chromagram extraction with the Tonnetz, a geometric representation of tonal relationships. We evaluate the impact of the Tonnetz and compare DTNs to state-of-the-art methods in both symbolic and audio domains. Our initial results demonstrate promising trends, with room for improvement. We also highlight the potential of integrating audio-based harmonic analysis with deep learning, providing a foundation for future research.
Functional Harmony, Deeplearning, Audio Processing
122
Subtle or Evident? Confidence Reports Indicate the Success of Adversarial Attacks in Humans
Trinidad Borrell and Enzo Tagliazucchi
Trinidad Borrell
While research shows that people can be vulnerable to adversarial perturbations, it remains unclear whether their influence operates similarly to artificial neural networks. Here, we investigate whether biases arise from explicit semantic content or if subtle attacks distort perception, causing subjects to exhibit bias without confidently articulating their reasoning.To address this, we conducted two forced-choice experiments with 20 participants: one with brief stimulus exposure and another with unlimited exposure. Adversarial perturbations of different magnitudes were designed to mislead an ensemble of six convolutional neural networks. Human responses, confidence levels, reaction times, and eye movements were recorded, and a post-hoc survey was conducted in the unlimited exposure experiment.Results indicate that in brief exposure, participants predominantly selected the original category, and when they did choose the adversarial category, they did so with low confidence. In one category pair, statistical significance showed that adversarial perturbations successfully misled participants. However, in unlimited exposure, perturbations had an evident effect, shown by increased confidence when selecting the adversarial image. This effect was linked to participants noticing alterations meant to deceive their classification or identifying semantic features resembling the target category, implying that misleads occur when adversarial attacks are evident rather than subtle.
adversarial attacks, human vision, computer vision
123
Decoding Marine Microbiome Life via Explainable Machine Learning
Luis Valenzuela, José Vásquez, Nayat Sánchez-Pi, Luis Martí
Luis Valenzuela
Oceans, covering over 70% of Earth’s surface, regulate the global climate by absorbing heat and CO2. Marine microbiomes support food webs and drive the biological carbon pump. However, the relationships between taxonomy, gene expression, metabolism, and environmental factors remain poorly understood.We applied Explainable Artificial Intelligence using Symbolic Regression and a SHAP-based approach to model these complex interactions with the OMR Gene Catalog, which contains 47 million genes annotated across 9,024 molecular functions. We generated 36,214 interpretable models, enabling the prediction of: (i) omics-derived features from environmental factors, (ii) relationships within taxonomic compositions, and (iii) taxonomic composition based on functional traits.Our results revealed that environmental factors predicted 22.6% and 29.4% of molecular functions and metabolic pathways from metagenomes, while only 4.9% and 3.5% were predicted from metatranscriptomes (R2 ≥ 0.5). The most accurate predictions involved molecular functions linked to carbon sequestration pathways. By providing a dataset of equations predicting omics-derived features, our work enables data-driven hypotheses on microbial function and taxonomic dynamics under environmental changes, as well as simulations of potential shifts under climate change scenarios.
explainable machine learning, metagenomics, marine microbiome
124
Reduction of instrumental effects an exoplanet finding spectrograph with supervised machine learning
Juan Serrano Bell, Rodrigo F. Díaz, Guillaume Hébrard
Rodrigo Díaz
The SOPHIE spectrograph, operational since 2006, enables detection of Earth-mass exoplanets through high-precision radial velocity (RV) measurements. However, systematic effects can cause variations in the nightly zero point (NZP), which are traditionally corrected using regular observations of standard stars. These systematic variations are believed to stem from residual environmental changes within the instrument and vary depending on the characteristics of the target star. We present a novel data-driven approach using machine learning to model and correct these NZP variations, incorporating housekeeping variables, stellar properties, and observational conditions. To validate our method, we tested it on 12 SOPHIE targets with known planetary companions, analyzing each system using three different sets of RVs: those processed with our correction method, those using the traditional master correction, and uncorrected data. Results demonstrate that both correction methods consistently outperformed uncorrected data, with our approach showing superior results in approximately half the cases. This demonstrates the effectiveness of our machine learning-based approach as a viable alternative to traditional NZP correction methods in high-precision RV measurements.
astronomy, supervised learning, systematic effects
125
A declarative language for explainability of probabilistic graphical models
Alexander Pinto, Marcelo Arenas
Alexander Pinto
Machine learning models, particularly sub-symbolic ones, have experienced rapid development and adoption across various fields. However, their complexity and opacity pose significant challenges for interpretation and justification. The field of Formal Explainable AI (FXAI) has emerged to provide rigorous, theoretically grounded explanations, addressing the limitations of heuristic explainability methods.Most work in formal explainability has focused on Boolean models. However, to address the inherent uncertainty in many real-world problems, it is necessary to consider models that incorporate probabilistic aspects. In this context, probabilistic circuits (PC) present themselves as a particularly promising class of probabilistic graphical models (PGM), combining the expressivity of neural networks with formal properties that facilitate their analysis.Our main objective is to develop the theoretical and practical foundations of a declarative language that allows users to formulate and execute explainability queries in PC models. Based on the extension of First-Order Interpretability Logic, we analyze expressivity limits, design tractable extensions, study computational complexity, and develop corresponding algorithms. This work contributes to FXAI by proposing an approach to improve the explainability of PGM.
explainable AI, probabilistic graphical models, logic
126
SHAP-Based Explainable Clustering for Medical Records Insights
Adriano Mauricio Lusso, Antonella Torres, Germán Braun , Christian Nelson Gimenez
Adriano Lusso
Machine Learning is a fundamental tool for information analysis. Among its various techniques, clustering stands out as a family of algorithms capable of dividing large datasets into distinct groups based on similarity. In the healthcare domain, state-of-the-art research has been conducted, leveraging the vast availability of patient medical data, which makes clustering a powerful tool for knowledge discovery. However, Machine Learning also presents limitations, such as difficulties in explaining its results and the potential for unethical biases, which pose significant challenges for real-world applications. This study explores opportunities for applying clustering techniques within the Social Security Insurance system of Universidad Nacional del Comahue, a university located in Neuquén, Argentina. Additionally, clustering will be combined with the SHAP framework to enhance the explainability of the obtained results.
AI in healthcare,clustering,SHAP
127
Characterization of the use of propaganda on social networks
Miguel Fernández, Maximiliano Ojeda, Lilly Guevara, Diego Varela, Marcelo Mendoza and Alberto Barrón-Cedeño
Lilly Guevara and Miguel Fernández
Identifying propaganda in social media posts is essential for understanding the strategies employed by policymakers and stakeholders to shape public perception. In this poster, we present our approach to the automated detection and characterization of propaganda techniques and narratives used by diplomats from major powers on social media. Our primary focus was to address class imbalances in the datasets provided for Task 1 of the DIPROMATS 2024 competition.Our initial evaluation revealed that certain propaganda techniques were underrepresented in the dataset. To address this, we implemented two data augmentation strategies to improve performance in these categories. The first strategy involved translating text samples between Spanish and English, enriching the dataset with new instances in both languages. The second strategy leveraged large language models (LLMs) to generate paraphrased samples, facilitating cross-lingual transfer between Spanish and English.Our solution ranked first in Subtask-1a for English (ICM score: 0.2123) and in the bilingual evaluation (ICM score: 0.2048).
Disinformation, Propaganda, LLMs
128
I Still Haven’t Found (What I’m Looking For): Cognitive-based visual search modeling
Gonzalo Ruarte, Matias J Ison, Juan E Kamienkowski
Gonzalo Ruarte
Human visual search is a complex, multifaceted process involving a sequence of eye movements to locate a target. While deep neural networks can predict eye movement patterns, they offer limited insight into the underlying cognitive mechanisms of attention, decision making, and working memory. By contrast, white-box approaches that explicitly model separate cognitive processes can clarify how the brain orchestrates search and guide AI systems under real-life constraints. We propose an iterative Bayesian decision-making model leveraging both prior knowledge and new information from each fixation. The prior is based on a saliency map while each fixation adds new information about the image. We are extending our model with segmentation and large language models to incorporate contextual information. By dissecting visual search into interpretable components, our framework offers a transparent way to study its cognitive foundations in humans and machines. Finally, our model closely replicates human behaviour across the datasets in the public ViSioNS benchmark.
Neuroscience, Visual Search, Cognition
129
Generalized Graph Variational Auto-Encoders
Kleyton da Costa (DI/PUC-Rio), Bernardo Modenesi (University of Utah), Ivan Menezes (DEM/PUC-Rio), Hélio Lopes (DI/PUC-Rio)
Kleyton da Costa
In this paper, we introduce the Generalized Graph Variational Auto-Encoder (GGVA), a novel framework that extends traditional Variational Graph Autoencoders by incorporating generalized divergence measures for distribution regularization in the latent space. Our main contributions are twofold: (1) a flexible variational inference framework for graph-structured data using generalized divergence measures, and (2) the empirical demonstration that these measures can improve accuracy in handling complex network topologies for link prediction tasks.
Learning on Graphs, Generalized Variational Inference, Generalized Divergence Measures, Link Prediction
130
Normalized vs Diplomatic Annotation: A Case Study of Automatic Information Extraction from Handwritten Uruguayan Birth Certificates
Natalia Bottaioli, Solène Tarride, Jérémy Anger, Seginus Mowlavi, Marina Gardella, Antoine Tadros, Gabriele Facciolo, Rafael Grompone von Gioi, Christopher Kermorvant, Jean-Michel Morel, and Javier Preciozzi
Natalia Bottaioli
This study evaluates the recently proposed Document Attention Network (DAN) for extracting key-value information from Uruguayan birth certificates, handwritten in Spanish. We investigate two annotation strategies for automatically transcribing handwritten documents, fine-tuning DAN with minimal training data and annotation effort. Experiments were conducted on two datasets containing the same images (201 scans of birth certificates written by more than 15 different writers) but with different annotation methods. Our findings indicate that normalized annotation is more effective for fields that can be standardized, such as dates and places of birth, whereas diplomatic annotation performs much better for fields containing names and surnames, which can not be standardized.
Automatic information extraction, Handwritten text recognition, Normalized and diplomatic annotation
131
Symmetry-Enhanced AI: Improving Mine Waste Storage Facilities Detection and Segmentation for Simplified Physical Stability Assessment in Chile
Giovanni Cocca-Guardia, Gabriel Hermosilla, Gabriel Villavicencio, Vicente Aprigliano, Manuel Silva, Juan Carlos Quezada, Pierre Breul, Vinicius Minatogawa and Jaime Morales
Giovanni Cocca Guardia
Chile’s mining industry, a global leader in copper production, faces challenges due to the increasing volumes of mining waste. These materials are disposed of in Mine Waste Storage Facilities (MWSFs), which pose significant environmental risks due to their large volumes and hazardous contents. These include Waste Rock Dumps (WRDs), Leaching Waste Dumps (LWDs), and Tailings Storage Facilities (TSFs). The National Geology and Mining Service (SERNAGEOMIN) requires the assessment of the physical stability (PS) of these facilities, but current methods are hindered by data scarcity and resource constraints. Our recent work proposed a simplified assessment methodology using first-order parameters derived from open-access data, integrating Sentinel-2 satellite imagery, geographic information systems (GIS), and artificial intelligence (AI) to automate the detection, segmentation, and remote evaluation of PS for WRDs and LWDs in the Antofagasta region. This study preliminarily extends the methodology to TSFs, incorporating symmetry properties into AI models to enhance the characterization of mining deposits despite satellite image limitations and their diverse visual representations.
mine waste storage facilities, artificial intelligence, physical stability assessment
132
SignAttention: On the Interpretability of Transformer Models for Sign Language Translation
Oscar Agustín Stanchi, Pedro Alejandro Dal Bianco, Facundo Manuel Quiroga, Franco Ronchetti, Enzo Ferrante
Oscar Agustín Stanchi
This paper presents the first comprehensive interpretability analysis of a Transformer-based Sign Language Translation (SLT) model, focusing on the translation from video-based Greek Sign Language to glosses and text. Leveraging the Greek Sign Language Dataset, we examine the attention mechanisms within the model to understand how it processes and aligns visual input with sequential glosses. Our analysis reveals that the model pays attention to clusters of frames rather than individual ones, with a diagonal alignment pattern emerging between poses and glosses, which becomes less distinct as the number of glosses increases. We also explore the relative contributions of cross-attention and self-attention at each decoding step, finding that the model initially relies on video frames but shifts its focus to previously predicted tokens as the translation progresses. This work contributes to a deeper understanding of SLT models, paving the way for the development of more transparent and reliable translation systems essential for real-world applications.
Sign Language Translation,Transformer,Interpretability
133
Deep Learning for COVID-19 in Lung CT: Comparative Perspectives on Segmentation Approaches
Sharon Quispe , Ingrid Arellano , Pedro Shiguihara , Sebastian Paucar and Jorge Valverde-Rebaza
Sharon Quispe Carhuapoma
Segmentation of lung regions affected by COVID-19 in chest CT scans is vital for reliable diagnosis and effectiveevaluation of the disease’s prognosis. Few studies establish a faircomparison of the segmentation methods of CT scans for auto-mated COVID-19 detection using datasets from the literature.Thus, hindering the ability to establish certainty in identifyingwhich method demonstrates consistency. Existing methods oftenrely on independent evaluations using diverse image datasets,leading to inconsistencies and limited comparability. This studyaims to set up a single experimental environment to ensure a fairassessment of the performance of methods from the literature.Additionally, this study incorporates an interpretability analysisbased on the Explainable artificial intelligence discipline, arecent research direction that aims to interpret deep learningmodels’ results. The research framework involves two stages:First, deep learning models are evaluated using standard methods such as dice score, pixel-wise precision, and intersectionover union metrics. Second, the application of the ConfusionMatrix Heatmaps technique to interpret model predictions byvisualizing the feature detection process, intending to benchmark their performance and understand their ability to detect and recognize critical features in medicalimaging tasks.
Image segmentation, COVID- 19, Explainable AI
134
Decoding embryonic development using deep learning
Hernán Morales-Navarrete, Ricardo Velasco
Hernan Andres Morales Navarrete
We explored the application of artificial intelligence to enhance our understanding of embryonic development. Previously, we introduced EmbryoNet, a deep convolutional neural network crafted for the automated phenotyping of zebrafish signaling mutants. This tool effectively identifies and classifies phenotypic anomalies induced by disruptions in critical signaling pathways. Currenlty, we are exploring the temporal evolution of embryo development using recurrent neural networks and autoencoders, aiming to uncover dynamic patterns and temporal relationships that drive developmental processes. These methodologies not only standardize phenotypic classification but also facilitate high-throughput drug screening and comparative embryology across various species.
Embryonic development, Deep learning, autoencoders
135
Demographic Biases and Gaps in the Perception of Sexism in Large Language Models
Judith Tavarez Rodríguez, Fernando Sánchez Vega, Adrián Pastor López Monroy
Judith Tavarez Rodríguez
The use of Large Language Models (LLMs) has proven to be a tool that could help in the automatic detection of sexism. Previous studies have shown that these models contain biases that do not accurately reflect reality, especially for minority groups. Despite various efforts to improve the detection of sexist content, this task remains a significant challenge due to its subjective nature and the biases present in automated models.We explore the capabilities of different LLMs to detect sexism in social media text using the EXIST 2024 tweet dataset. It includes annotations from six distinct profiles for each tweet, allowing us to evaluate to what extent LLMs can mimic these groups’ perceptions in sexism detection. Additionally, we analyze the demographic biases present in the models and conduct a statistical analysis to identify which demographic characteristics (age, gender) contribute most effectively to this task.Our results show that, while LLMs can to some extent detect sexism when considering the overall opinion of populations, they do not accurately replicate the diversity of perceptions among different demographic groups. This highlights the need for better-calibrated models that account for the diversity of perspectives across different populations.
Sexism Perception, Large Language Models, Demographic Bias
136
Viral Networks: Enhancing Epidemiological Response by Targeting Fast-Growing Disease Clusters
Rocío Carrasco-Hernández , Humberto Valenzuela-Ponce, Maribel Soto-Nava, Claudia García-Morales, Margarita Matías-Florentino, Joel O. Wertheim, Davey M. Smith, Gustavo Reyes-Terán, Santiago Ávila-Ríos
Rocío Carrasco Hernández
AbstractTimely identification and analysis of disease transmission networks is becoming an emerging approach for understanding and mitigating the local spread of infectious diseases such as HIV and Hepatitis C. At the Centro de Investigación en Enfermedades Infecciosas, Mexico, we collect blood samples from local clinics, of people infected and sequence specific viral genes. Using bioinformatic tools (e.g. HIV-TRACE), we construct putative transmission networks by linking sequences with genetic distances below 1.5%. These networks allow us to identify clusters of related cases, which serve as epidemiological units of study. By analyzing cluster properties, such as size and connectivity, we investigate associated genetic, clinical, and demographic risk factors that contribute to the dynamics of viral spread.Despite the utility of these networks, the computational demands of network-building algorithms, particularly when applied to large datasets, remain a significant challenge. Artificial intelligence (AI) could offer transformative potential in this domain by improving the scalability, speed, and accuracy of network construction. Machine learning models could assist in optimizing sequence similarity thresholds, predicting cluster growth, and identifying key drivers of transmission.
Pandemics, Genetic Sequences, Networks
137
Energy, Weather, and AI: Short-Term Electricity Demand Forecasting Model
Uhrig, Mariela N., Leandro D. Vignolo, and Omar V. Müller
MARIELA NOELIA UHRIG
The province of Entre Ríos (Argentina) lacks an automated model for electricity demand forecasting, which would notably enhance its management and daily operations. Accurate prediction remains a challenge due to the non-linear nature of electricity consumption. This work addresses this challenge using deep learning techniques with demonstrated success in time series prediction and growing application in energy forecastingWe propose an LSTM-based model for short-term electricity demand forecasting using a recurrent neural network (LSTM) capable of capturing temporal dependencies without manual feature extraction. The model takes as input a combination of meteorological variables (e.g., temperature, humidity) and energy-related variables (e.g., historical demand, time of day) to predict electricity demand. We evaluated various temporal window configurations and other hyperparameters to assess their impact on predictive performance. Results demonstrate that the LSTM model effectively captures temporal dependencies, providing accurate demand forecasts compared to classical methods. This study highlights the potential of deep learning for optimizing energy system operations and supporting decision-making in power management
electricity demand forecasting, deep learning, times series prediction
138
Cross-lingual Multitask Learning for Rumor Detection
Eliana Providel, Marcelo Mendoza, Mauricio Solar
Eliana Providel
Rumor detection has been widely studied from various perspectives and across multiple languages. However, for low-resource languages, such as Spanish, research remains limited due to the lack of labeled datasets necessary for training neural networks. In this work, we address this challenge by leveraging datasets from related tasks, including stance classification with English data and bot detection with both English and Spanish data. Our study explores how these datasets can support and transfer knowledge to improve rumor detection in Spanish.
Rumor Detection, Multitask, Deep Learning
139
MangroveNet: mapping and monitoring mangrove ecosystems based on U2-Net model using Satellite Images
Manuel Josue Malla Campoverde - Universidad Técnica de Machala, Eduardo Alejandro Tusa Jumbo - Universidad Técnica de Machala
Manuel Josue Malla Campoverde
Mangrove ecosystems are vital for biodiversity conservation and coastal protection but face severe threats from human activities, particularly in El Oro, Ecuador. This study presents MangroveNet, an advanced deep learning approach for mapping and monitoring mangrove forests using U2-Net and multispectral satellite data from Landsat and Sentinel-2. By integrating six spectral bands (RGB, NIR, SWIR-1, SWIR-2) and four multispectral indices (NDVI, NDWI, NDMI, MNDWI), our model achieves precise segmentation of mangrove areas. Unlike traditional methods, U2-Net's multi-scale feature extraction enhances accuracy in complex landscapes, enabling better tracking of deforestation and ecosystem changes. Performance is evaluated using Precision, Recall, Intersection over Union (IoU), and Dice score, ensuring robust segmentation. The results provide critical insights for conservation strategies, supporting reforestation efforts and sustainable management policies. This study demonstrates the potential of deep learning and remote sensing in environmental monitoring, offering a scalable solution for real-time mangrove ecosystem assessment.
Deep Learning, Remote Sensing, Segmentation
140
Thesis proposal: At the interface of Natural Semantic Metalanguage and Artificial Intelligence
Lenin Pavón Alvarez & Ximena Gutiérrez Vasques
Lenin Pavón Alvarez
Natural Semantic Metalanguage, theory formalized by Anna Wierzbicka, proposes a set of words whose meaning is universal across languages and cultures. Through this framework several datasets and academic papers have been published, along them the Longman Common Dictionary of English rewritten to be NSM-compliant. However, there is a gap in the literature regarding the complexity behind the induced network of semantic relationships. Through the study of this network, we may be able to create new architectures that are more efficient and allow us to inspire and analogous Physics Informed Neural Operator for Language Models.
Natural Semantic Metalanguage, Neural Networks, Semantics
141
Considerations on Open Science from Researchers in the Global South: An Analysis Using NLP Tools
Jesica Formoso, María Cristina Nanton, Patricia Loto
Jesica Formoso
The adoption of Open Science practices in Latin America presents both challenges and opportunities. This study examines the perceptions of 285 Spanish-speaking researchers and technicians regarding the barriers to Open Science implementation and its impact on the relationship between the scientific community and the public. To explore these perspectives, we apply a text mining approach using tools from the tidy ecosystem in R.Data were collected from registration forms for an Open Science training conducted in 2024 by MetaDocencia, based on NASA materials contextualized into Spanish. We employed classical NLP techniques, including frequency analysis, tf-idf computation, sentiment analysis, and topic modeling. The findings offer a structured overview of key challenges, such as institutional barriers and a lack of incentives, as well as expected benefits, including increased transparency and public trust. This study enhances our understanding of how the research community perceives the transition to Open Science and provides valuable insights for designing strategies that support its implementation.
Natural language processing, open science, researcher's perception
142
Reduced Representations of Turbulent Rayleigh-Bénard Flows via Autoencoders
Melisa Vinograd and Patricio Clark di Leoni
Melisa Vinograd
We analyzed the performance of Convolutional Autoencoders in generating reduced-order representations the temperature field of 2D Rayleigh-Bénard flows at $\Pr=1$ and Rayleigh numbers extending from $10^6$ to $10^8$, capturing the range where the flow transitions to turbulence.We present a way of estimating the minimum number of dimensions needed by the Autoencoders to capture all the relevant physical scales of the data that is more apt for highly multiscale flows than previous criteria applied to lower dimensional systems.We compare our architecture with two regularized variants as well as with linear methods, and find that manually fixing the dimension of the latent space produces the best results.We show how the estimated minimum dimension presents a sharp increase around $Ra\sim 10^7$, when the flow starts to transition to turbulence. Furthermore, we show how this dimension does not follow the same scaling as the physically relevant scales, such as the dissipation lengthscale and the thermal boundary layer.
Turbulence, Dimensionality reduction, autoencoders
143
Fair Mixture of Probabilistic Principal Component Analyzers
Beatriz Cardoso Nascimento, Marcos Medeiros Raimundo, Alessandro Gaio Chimenton
Beatriz Nascimento
Principal Component Analysis (PCA) is a widely used technique for data processing, compression, and visualization. However, its reliance on linear projections and the absence of mechanisms to ensure fairness introduce significant limitations in many practical applications. To address these challenges, we propose a novel framework based on a mixture of Probabilistic Principal Component Analyzers (PPCA). This approach allows for the modeling of complex, nonlinear data structures while incorporating explicit controls for fairness across distinct groups. Our method leverages a probabilistic foundation to ensure robustness and interpretability, with applications spanning diverse domains where ethical and unbiased data representation is critical.
Mixture Models, Fairness, Dimensionality Reduction
144
Empowering teachers with AI for participatory bias assessment of language technologies: Scaling teachers’ engagement to Latin America
Luciana Benotti, M. Emilia Echeveste, Marcos J Gomez, Guido Ivetta, Pietro Palombini, Laura Alonso Alemany, Nair Carolina Mazzeo, Beatriz Busaniche
Pietro Palombini
Es el resumen del proyecto de Google Assessing AI technology for biased and toxic behaviors is a crucial issue in developing human-centered applications based on AI. Existing approaches often fail to take into account culturally situated evaluations and lack representation from marginalized regions like Latin America. There are significant challenges in obtaining rich socio-cultural knowledge that requires community engagement. Empowering high-school teachers and their students to carry out such assessments themselves contributes to creating a responsible ecosystem, where they can understand the risks and make informed decisions on how to use AI. We are carrying out a large professional development (PD) course in Argentina with 30 university professors, 400 high school teachers, and 6K students that empower high school teachers and students to carry out such assessments systematically, as we teach them how they can use generative AI tools responsibly in their daily tasks. Teachers and students will generate outputs based on diverse prompts, analyze potential stereotypes and biases in these outputs, and validate findings with socio-cultural perspectives specific to Latin America. As a by-product of the exploration of biases carried out by teachers and students, datasets that represent harmful stereotypes are also produced, validated, and consolidated to assess biases and other risks in language technologies. This project proposes to scale this initiative to other 4 countries in Latin America: Brazil, México, Chile and Uruguay. Almost 400 million people, more than 60% of the latinamerican population, live in one of these 5 countries. We will investigate differences in methodology required by different cultures and contexts of application, and diversify and consolidate materials and methodologies adequate to those contexts. We will release the created datasets so that future work on society-centered AI can evaluate alignment in a more culturally aware way in Latin America.
AI ethics education, hands-on workshop, AI biases, teachers professional development
145
Identifying Exoplanet Transit Candidates in TESS Full-Frame Image Light Curves
Yesenia Helem Salinas, et al.
Yesenia Helem Salinas
The study of planetary transits is essential for detecting and characterizing exoplanets, enabling the analysis of their physical, atmospheric, and orbital properties, and improving our understanding of planetary system formation. As astronomical datasets, such as those from the operational Transiting Exoplanet Survey Satellite (TESS), survey a large fraction of the sky, they generate a vast database of photometric time series with the goal of identifying exoplanets. This work presents a Transformer-inspired neural network to detect exoplanet transit signals directly from Full Frame Image (FFI) light curves in the 30-minute cadence data, without relying on periodicity, prior transit parameters, or phase folding. The network is trained to learn characteristics of the transit signal, such as the dip shape, which helps distinguish planetary transits from other variability sources, such as eclipsing binaries. Our method successfully identified new planetary system candidates from TESS sectors 1-26 with a radius greater than 0.27 Jupiter radius. With inference times of just milliseconds per light curve, the TESS 30-minute cadence dataset can be processed efficiently, enabling real-time analysis of new data.
Astronomy, Exoplanets, Machine Learning
201
Sof+IA a feminist chatbot to report Digital Gender Violence on social media
Patricia Peña, Daniela Moyano
Patricia Peña
The poster presents the design of SOF+IA (Sistema de Oída Feminista), a technological prototype, under development, of a chat-bot (conversational agent) that allows reporting digital gender-based violence (DGBV) on social networks, anonymously, and providing information to women who experience it daily in Chile. DGBV is a growing problem, especially with the modification of content moderation policies on the main social networks and the lack of regulation of this problem in the country. Programmed as a conversational AI, it works on a web platform (https://sofiachat.cl/), to provide guidance as a helpline to address and prevent it with digital security recommendations. The report can be downloaded as a record, if the person needs to use this information. Also generates a database that visualises the occurrence of these cases for public visibility, research and advocacy.Sof+IA has been designed with UX methodology and feminist co-design principles and tested with women with a public voice such as activists, leaders, academics, among others who live this type of situation on a daily basis. This has allowed us to identify errors, improve aspects such as anonymity, privacy and system violations.
Digital gender violence, feminist chatbot, feminist AI
202
A detection system for hydrocarbon-derived pollutants in water using surface-enhanced Raman spectroscopy and machine learning.
Ayelen Arias, Esteban Roitberg, Julian Gargiulo, Ianina Violi, Fernanda Cardinal
Ayelen Arias
Argentina is the second-largest unconventional hydrocarbon reservoir. Its extraction can contaminate significant volumes of water with toluene and xylene, compounds harmful to both human health and the environment. Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive technique for molecules detection. We developed a detection system for toluene and xylene in water using SERS and machine learning. A custom dataset of Raman spectra was collected from pure water and artificially contaminated samples at varying concentrations. A comprehensive workflow was implemented for preprocessing and feature extraction. Three distinct feature sets were evaluated: two derived programmatically and one based on expert knowledge. Various classifiers were trained to predict both the identity and concentration of contaminants. When distinguishing pure water from contaminated samples, accuracies ranged from 0.87 to 0.91. More complex tasks, such as predicting both the identity and concentration of contaminants, achieved 0.78 accuracy using expert knowledge-based features, and 0.78 to 0.87 for the programmatic methods. The proposed methodology effectively identified varying concentrations of toluene and xylene, underscoring the importance of expert knowledge in feature selection for machine learning applications in water pollution detect.
dataset, feature engineering, pollutant detection
203
Innovating Environmental Policy Monitoring in Guatemala with Computer Vision
UNDP Accelerator Lab Guatemala, SDG AI Lab
Carlos Mazariegos
This project aims to identify illegal waste dumping sites in Guatemala through state-of-the-art geographical information systems (GIS), computer vision and machine learning methods. Co-led by UNDP Accelerator Lab Guatemala and SDG AI Lab, and in collaboration with Politecnico di Milano (Polimi), the project uses satellite imagery analysis to facilitate efficient and cost-effective monitoring of dumpsites. This joint effort aligns with the strategic goals of the National Development Plan and Country Priorities.
climate action, computer vision, policy monitoring
204
Revealing distributed and multiplexed information in the brain with neuronal encoding and decoding models
Facundo Montiel, Juan Ignacio Ponce, Lucca Salomon, Sol Ramos, Noel Federman, Antonia Marin-Burgin, Sebastián A. Romano
Facundo Montiel
To understand the brain, we must examine how it represents information through neuronal activity patterns. We present an example of how Machine Learning offers a powerful framework for this task. The current paradigm in Neuroscience posits a hierarchical functional model of the brain, where complex information essential for cognition and behavior is only represented in higher-order brain areas, while lower-level areas specialize on simpler sensory and motor processing. We provide evidence that challenges this view. In a virtual reality setup, we trained mice to pair odors with virtual environments and recorded neuronal activity from the primary olfactory cortex (a “low-level” sensory processor) and the hippocampus (an integrative area involved in memory and spatial cognition). Neuronal encoding models based on Generalized Linear Models reveal that the olfactory cortex encodes olfactory information, spatial location, running speed, and other behavioral and cognitive variables. Furthermore, feed-forward and recurrent neural networks trained to decode spatial information from neuronal activity show similar accuracies in both the olfactory cortex and hippocampus. These results indicate that complex and multiplexed information is already present at early sensory processing stages, challenging the traditional hierarchical model. This supports a more distributed and decentralized view of brain organization.
computational neuroscience, brain decoding, neuronal networks
205
Deep Learning in Fluid Dynamics: FNO-Based Neural Networks for Direct and Inverse Modeling of Channel Flow
Jonathan Poblete, Yarko Niño, Luis Zamorano
Jonathan Poblete
This study presents a novel application of Fourier Neural Operators (FNO) for modeling water flow in channels, addressing both direct simulation and inverse problem solving. Using TELEMAC2D simulations, we trained neural networks to either predict flow characteristics or reconstruct channel bed geometry from surface velocities. The models incorporate physics-informed loss functions based on shallow water equations and demonstrate successful dimensionless parameter handling. Our results show promising performance in both direct simulation acceleration and bottom geometry inference, with effective transfer learning capabilities across different geometry types. This approach offers a computationally efficient alternative to traditional numerical methods while maintaining physical consistency.
Fourier Neural Operators (FNO), Computational Fluid Dynamics, Deep Learning
206
Challenges and New Questions for Security Engineering in ML
Enrique Chaparro
Enrique Chaparro
Safe ML systems are a common goal, but safety implies security, and security requires engineering. Beyond the risks common to any computer system, ML systems pose a new set of risks.Current status in the ML world seems the “penetrate and patch” hamster-wheel-like process which was common on the field of software security by the end of the past century. Early work in security and privacy of ML has taken more of an “operations security” tack focused on securing an existing ML system and maintaining its data integrity. This work in progress aims to contribute to the foundation of good security engineering practices specific to ML.In our view architectural risk analysis (ARA) is needed at this stage. An ARA takes a design-level view of a system and teases out systemic risks so that those risks can be properly mitigated and managed as a system is created. In general an ARA is much more concerned with design tradeoffs and solid engineering than it is with particular bugs in a specific system or individual lines of code. Other security guidelines are explored, e.g. Saltzer-Schroeder principles and IEEE Top Software Security Design Flaws.
security engineering, architectural risk, attack surfaces
207
Optimal Transport-Based Transfer Learning Across Subjects for Brain-Computer Interfaces with Minimal Calibration
Catalina M. Galván, Diego H. Milone, Rubén D. Spies, and Victoria Peterson
Catalina Maria Galvan
Training machine learning models to decode motor imagery (MI) brain activity from electroencephalography (EEG) signals requires extensive subject-specific data, leading to tedious calibration sessions. This limits practical application of brain-computer interfaces (BCIs) based on MI. A promising strategy to shorten calibration is leveraging available data from other subjects through transfer learning. However, EEG signals exhibit high inter-subject variability, which we propose to mitigate through an effective domain adaptation strategy.Here, we use a supervised version of the backward optimal transport for domain adaptation method to align the features from a target subject with the distribution from training subjects. The decoding model is first trained on MI-EEG data from multiple subjects and a small set of target subject data is used to learn the transport mapping, adapting the features while keeping the trained model frozen. Experiments on publicly available EEG datasets show that our approach significantly outperforms the model trained without adaptation and fine-tuning and retraining strategies.These findings demonstrate that optimal transport-based adaptation can effectively mitigate inter-subject variability in EEG data, enabling accurate decoding with subject-specific minimal calibration, and enhancing the usability of MI-BCIs in practical applications like motor rehabilitation.
Brain Computer Interfaces, Transfer Learning, Optimal Transport
208
Artificial Neural Networks
Rubenia Borge
Rubenia Borge
This poster presents the building blocks of neural networks and an analysis of why these function estimators are so widely used in Artificial Intelligence.
Artificial, Neural, Networks
209
Optimizing Academic Performance by applying Data Science to the Entrance Exam
Israel N. Chaparro-Cruz, Luciana N. Huertas-Condori, Silvana B. Cabana-Yupanqui, Americo Chaparro-Guerra
Israel Nazareth Chaparro Cruz
This study applies data science techniques to analyze the relationship between entrance exam scores and academic performance, with a focus on optimizing student retention at Jorge Basadre Grohmann National University (UNJBG). Using a dataset of 1,526 students admitted in 2017 and tracked through 2024, we employ machine learning models and statistical methods to uncover patterns in admission scores, academic success, and dropout. Key findings confirm that Verbal Reasoning and Language are moderately correlated with academic performance, while discipline-specific subjects such as Biology and Mathematical Reasoning exhibit varying degrees of influence depending on the field of study. Furthermore, predictive models highlight a strong inverse relationship between admission scores and dropout rates, with Spearman correlations of -0.8 (average scores) and -0.77 (minimum scores). Leveraging these insights, we propose a data-driven admission framework that dynamically adjusts minimum score thresholds per study track, aiming to enhance retention without compromising accessibility. For instance, our model suggests that optimizing admission criteria for Health and Biomedical Sciences could reduce dropout rates by 24.29% while only decreasing admissions by 16.56%. This research demonstrates the potential of data science to refine higher education admission policies in the Peruvian academic landscape.
data science, academic performance, entrance exam
210
APPLICATION OF SELF-SAMPLING FOR TREE SEGMENTATION IN A SCENARIO OF LIMITED LABELS
Luiz Fernando Souza Luz, Matheus Pinheiro Ferreira, Laura Elena Cué la Rosa, Hudson Franklin Pessoa Veras, Ernandes Macedo da Cunha Neto, Evandro Orfanó Figueiredo, Ana Paula Dalla Corte, Carlos Roberto Sanquetta e Dário Augusto Borges Oliveira
Luiz Luz
This work explores the application of a self-sampling method in Deep Learning models for instance segmentation of tree species using remote sensing images. The aim is to develop an effective method capable of mapping different tree species in forest areas with high precision, even when faced with a limited initial set of annotated data. The proposed approach aims to cover a larger area of the forest while maintaining satisfactory prediction quality. The introduction of these techniques resulted in an increase in the model’s segmentation coverage from 4.4% to 23.7% of the study area, while maintaining a high macro-average F1-Score, ranging between 60% and 45%.
Self-Sampling, Deep Learning, Remote Sensing, Forest Monitoring, Instance Segmentation
211
Measuring Speech Rate Using Pre-Trained Models
Tomas Palazzo and Pablo Riera
Tomas Palazzo
Speech analysis has long been considered an attractive case study in the scientific field. Studying speech rate can be useful in areas such as health and education. Historically, measuring speech rate has been based on counting syllables from audio signals, utilizing techniques ranging from classical signal processing to more modern approaches like convolutional neural networks.In this study, neural networks pre-trained for the task of phoneme alignment in texts will be used to evaluate speech rate, encompassing both average and instantaneous rates. By exploring various attributes, we developed a model that accurately predicts speech rate, valid for evaluations of both average rate (with pauses R² ≈ 0.725, without pauses R² ≈ 0.726) and instantaneous rate (with pauses R² ≈ 0.728, without pauses R² ≈ 0.725).
Speech Rate, Linguistics, Text Alignment
212
Automatic Strain Quantification in Cardiac Magnetic Resonance Images
Agustín Bernardo, Germán Mato, Matías Calandrelli, Jorgelina Medus and Ariel Curiale
German Mato
We introduce a deep learning method for myocardial strain analysis while also evaluating the efficacy of the method across a public and a private dataset for cardiac pathology discrimination. We measure the global and regional myocardial strain in cSAX CMR images by first identifying a ROI centered in the LV, obtaining the cardiac structures (LV, RV and Myo) and estimating the motion of the myocardium. Finally, we compute the strain for the heart coordinate system and report the global and regional strain. We validated our method in two public datasets and a private dataset, containing healthy and pathological cases (acute myocardial infarction, DCM and HCM). We measured the mean Dice coefficient and Hausdorff distance for segmentation accuracy, and the absolute end point error for motion accuracy, and we conducted a study of the discrimination power of the strain and strain rate between populations of healthy and pathological subjects. The results demonstrated that our method effectively quantifies myocardial strain and strain rate, showing distinct patterns across different cardiac conditions achieving notable statistical significance.
deep learniing, medical imaging, cardiac strain
213
Pixel-Wise Recognition for Holistic Surgical Scene Understanding
Nicolás Ayobi, Santiago Rodríguez, Alejandra Pérez, Isabela Hernández, Nicolás Aparicio, Eugénie Dessevres, Sebastián Peña, Jessica Santander, Juan Ignacio Caicedo, Nicolás Fernández, and Pablo Arbeláez
Nicolas Aparicio
This poster presents the Holistic and Multi-Granular Surgical Scene Understanding of Prostatectomies (GraSP) dataset, a curated benchmark that models surgical scene understanding as a hierarchy of complementary tasks with varying levels of granularity. Our approach encompasses long-term tasks, such as surgical phase and step recognition, and short-term tasks, including surgical instrument segmentation and atomic visual actions detection. To exploit our proposed benchmark, we introduce the Transformers for Actions, Phases, Steps, and Instrument Segmentation (TAPIS) model, a general architecture that combines a global video feature extractor with localized region proposals from an instrument segmentation model to tackle the multi-granularity of our benchmark. Through extensive experimentation in ours and alternative benchmarks, we demonstrate TAPIS's versatility and state-of-the-art performance across different tasks. This work represents a foundational step forward in Endoscopic Vision, offering a novel framework for future research towards holistic surgical scene understanding.
Robot-Assited Surgery, Prostatectomy Procedures, Transformers
214
Riometry data processing techniques in the fifth era of technology
Pedro González Soto, Gonzalo Burgos, Rodrigo Reeves, Miguel Martínez-Ledesma, Manuel Bravo, Guillermo Rodríguez, Ricardo Ezequiel García, Alberto José Foppiano
Pedro Gonzalez Soto
Advances in geophysical and astronomical instrumentation have significantly increased data throughput by enhancing sensitivity, bandwidth, and sensing channels. Modern digital technologies have exponentially expanded data volumes, posing challenges in storage, retrieval, and analysis. To address this, the Ionospheric Spectral Imager (ISI), a new FPGA-based multispectral riometer, is being developed to handle vast daily data with intensive real-time analysis. Machine Learning (ML) algorithms for dimensional reduction and clustering are proposed to efficiently process Cosmic Noise Absorption (CNA) images. Opacity functions of CNA are generated, and Principal Component Analysis (PCA) is applied to estimate variance explained by different components. To validate this approach, CNA was analyzed using data from Trelew’s 2D SARINET riometer. Dimensionality reduction and clustering techniques were applied to track the temporal evolution of principal components during the March 11, 2015 solar flare. This event, identified blindly from the data without prior information, demonstrated the effectiveness of the proposed analysis method.
Riometer, Machine Learning, Cosmic Noise Absorption
215
A Hybrid Supervised and Self-Supervised Graph Neural Network for Edge-Centric Applications
Eugenio Borzone, Leandro Di Persia and Matias Gerard
Eugenio Borzone
This work presents a novel graph-based deep learning model for tasks involving relations between two nodes (edge-centric tasks), where the focus lies on predicting relationships andinteractions between pairs of nodes rather than node properties themselves. This model combines supervised and self-supervised learning, taking into account for the loss function the embeddings learned and patterns with and without ground truth. Additionally it incorporates an attention mechanism that leverages both node and edge features. The architecture, trained end-to-end, comprises two primary components: embedding generation and prediction. First, a graph neural network (GNN) transform raw node features into dense, low-dimensional embeddings, incorporating edge attributes. Then, a feedforward neural model processes the node embeddings to produce the final output.Experiments demonstrate that our model matches or exceeds existing methods for protein-protein interactions prediction and Gene Ontology (GO) terms prediction. The model also performs effectively with one-hot encoding for node features, providing a solution for the previously unsolved problem of predicting similarity between compounds with unknown structures.
GNN, Edge-centric, Property Prediction
216
Spectrogram Inpainting for Epileptogenic Pattern Detection with Probabilistic Diffusion Models
Damonte Aparicio Rocío
Rocío Damonte Aparicio
Spectrograms are key in the study of invasive electroencephalograms (iEEG) since they help with the detection of epileptogenic patterns. The responsive neurostimulator (RNS) system records iEEG data in basal state as well as during epileptogenic patterns, and it stimulates the epileptogenic focus. Unfortunately, this system cannot sense and stimulate at the same time. Therefore, during the stimulation time, there are blanks in the information given by the iEEG. This results in gaps in the spectrograms, which make the detection of epileptogenic patterns difficult. To overcome this challenge, the use of probabilistic diffusion models for spectrogram inpainting is explored. In this study, an AI based on denoising diffusion probabilistic models (DDPM) is being implemented. The final objective is to test the results with iEsPnet, an AI that can detect epileptogenic patterns with 90% of reliability. These findings give the necessary information to adjust the RNS. Consequently, better stimulation and more effective treatment of epilepsy should be achieved.
Inpainting, denoising diffusion probabilistic models (DDPM), invasive electroencephalograms (iEEG)
217
Identification of climate change and sustainability texts using pre-trained Spanish language models
Gerardo Huerta Robles , Gabriela Zuñiga-Rojas
Gabriela Zuñiga Rojas
This study presents a method to identify texts related to climate change and sustainability in Spanish using pre-trained language models. The objective is to develop a tool that identify among different texts those that address topics such as climate change and its effects. A dataset labeled with Spanish texts was created, the model was trained with this data and evaluated using a validation set, achieving an accuracy of 0.916. F1 Score of 0.95 and Recall of 0.99. The results show the effectiveness of the proposed approach to identify relevant texts on climate change in Spanish. This model can be a useful tool to create and enrich repositories on the subject, thus contributing to a greater awareness and understanding of climate change and its effects.
climate change, text identification, pre-trained Spanish language models
218
CAMPEONES: Continuous Annotation and Multimodal Processing of EmOtions in Naturalistic EnvironmentS – Pilot Data and Preliminary Analysis
D'Amelio, Tomás Ariel; Rodriguez Cuello, Jerónimo; Aboitiz, Julieta; Bruno, Nicolás Marcelo; Cavanna, Federico; De la Fuente, Laura Alethia; Muller, Stephanie; Pallavicini, Carla; Engemann, Denis-Alexander; Vidaurre, Diego; Tagliazucchi, Enzo
Tomás Ariel D'Amelio
This study at the intersection of affective neuroscience and artificial intelligence presents a pilot version of a public database that integrates real-time self-reports of emotional experiences in immersive virtual reality (VR) environments with simultaneous physiological measurements. In the experiment, all emotional annotations were recorded using a joystick that continuously captured the trajectories of participants' ratings. We assess the potential relationship between subjective emotional reports and peripheral physiological signals. By using VR to elicit realistic and controlled emotional responses, our methodology ensures high quality data and lays the foundation for the implementation of AI models capable of predicting the temporal evolution of affective states. Ultimately, this framework aims to deepen our understanding of the interplay between subjective emotional experience and its physiological correlates, providing valuable insights for future applications in affective computing.
Affective Computing, Virtual Reality, Physiology
219
Classifying Cognitive Task Performance in EEG Data Using Ensemble Learning and Hankel Matrix Eigenvalue Features
Ana Marcillo-Vera, Karen Cáceres-Benítez
Ana Marcillo Vera and Karen Cáceres
This study explores the classification of cognitive task performance quality using EEG data recorded during arithmetic problem-solving. Ensemble learning methods are employed to address the complexity of EEG signals. Advanced feature extraction techniques, including eigenvalue decomposition and Hankel matrices, transform sequential EEG time series into structured representations that capture time-locked correlations and dynamic neural behavior. Quantitating principal dynamic modes through eigenvalue analysis reveals the magnitude and distribution of eigenvalues, offering insight into underlying neural processes. Experimental results demonstrate robust classification performance. The CatBoost boosting model attained 86.9% accuracy, 92.1% AUC, and an F1-score of 86.4%, outperforming other ensemble approaches. Soft Voting classifiers also yielded high accuracy and AUC. A standalone Support Vector Machine (SVM) surpassed all ensemble models. Finally, With Hyperband optimization, SVM achieved the highest accuracy of 91.04%, an AUC of 0.950, and an F1-score of 0.909, emphasizing the impact of hyperparameter tuning. In future work, we will apply this approach to a dataset that uses cognitive tests to collect EEG signals in environments analogous to microgravity, aiming to explore cognitive performance in space missions.
EEG Classification, Ensemble Learning, Feature Extraction
220
Balance Heuristics for Off-Policy Evaluation with Multiple Behaviors in Reinforcement Learning
Amanda Camacho Novaes de Oliveira, Daniel Ratton Figueiredo, Bruno Castro da Silva
Amanda Camacho Novaes de Oliveira
In the era of artificial intelligence, each day it becomes more evident the potential of its methods, and the incredible things they can achieve. A great part of these advancements is due to reinforcement learning (RL), one of the three main paradigms in machine learning. RL is based on human learning, where an agent learns through experience to maximize the rewards it receives as a consequence of its actions.Within the broad RL field, the ideas of off-policy evaluation (OPE) have emerged with the intent of utilizing historical data to boost RL applications. For safety-constrained environments, where one cannot randomly interact with the environment without possibly causing harm, utilizing historical data is often the only option to train RL agents. However, OPE methods typically have high variance, which often makes them unsuitable for many practical applications.As an attempt to help mitigate this issue, this preliminary work proposes a framework that combines data from multiple logging policies to provide better off-policy estimates. This framework incorporates multiple importance sampling (MIS) with the balance heuristics method to traditional OPE estimations.
Reinforcement Learning, Off-Policy Evaluation, Multiple Importance Sampling
221
Repulsive Latent Score Distillation for Solving Inverse Problems
Nicolas Zilberstein, Morteza Mardani, Santiago Segarra
Nicolas Zilberstein
Score Distillation Sampling (SDS) has been pivotal for leveraging pre-trained diffusion models in downstream tasks such as inverse problems, but it faces two major challenges: mode collapse and latent space inversion, which become more pronounced in high-dimensional data. To address mode collapse, we introduce a novel variational framework for posterior sampling. Utilizing the Wasserstein gradient flow interpretation of SDS, we propose a multimodal variational approximation with a repulsion mechanism that promotes diversity among particles by penalizing pairwise kernel-based similarity. This repulsion acts as a simple regularizer, encouraging a more diverse set of solutions. To mitigate latent space ambiguity, we extend this framework with an augmented variational distribution that disentangles the latent and data. This repulsive augmented formulation balances computational efficiency, quality, and diversity. Extensive experiments on linear and nonlinear inverse tasks with high-resolution images (512x512) using pre-trained Stable Diffusion models demonstrate the effectiveness of our approach.
diffusion models, inverse problems, accelerated sampling
222
Transformers for Genomic Prediction: working with Yeast and Wheat traits
Graciana Castro, María Inés Fariello, Romina Hoffman, Federico Lecumberry, Mateo Musitelli
Graciana Castro
Genomic prediction, Deep Learning, Transformers
223
Learning Low-Dimensional Manifolds for Path Integration in Neural Networks
Facundo Emina, Emilio Kropff
Facundo Emina
Path integration (PI) enables autonomous agents to track their position in space without external cues, a fundamental capability for navigation. In the mammalian brain, this function is thought to be implemented by grid cells—neurons in the entorhinal cortex that exhibit periodic spatial firing patterns. These cells are believed to integrate speed and direction information, with their activity emerging from either recurrent attractor networks or self-organizing feedforward networks. While recurrent attractor models naturally support PI, they typically rely on rigid, ad hoc connectivity patterns, which can limit their flexibility. In contrast, feedforward models are more adaptable and capable of learning representations, although they have traditionally not been associated with PI. In this work, we explore how unsupervised learning mechanisms in feedforward networks can support PI. Using numerical simulations, we show that adaptive and competitive networks can learn attractors from a tutor signal using Hebbian plasticity rules, encoding low-dimensional manifolds that enable spatial navigation. Our findings provide a potential bridge between representation learning in neural networks and biological navigation. Furthermore, this biologically inspired approach shares similarities with challenges in robotics—particularly in Simultaneous Localization and Mapping (SLAM)—and may offer insights for developing more robust, landmark-independent navigation strategies.
path integration, unsupervised learning, feedforward networks
224
Back to the Basics on Predicting Transfer Performance
Levy Chaves, Eduardo Valle, Alceu Bissoto, Sandra Avila
Levy Chaves
In the evolving landscape of deep learning, selecting the best pre-trained models from a growing number of choices is a challenge. Transferability scorers propose an efficient alternative by calculating a proxy to rank a pool of pre-trained model candidates. But, their recent proliferation, ironically, poses the challenge of their own assessment. In this work, we propose both robust benchmark guidelines for transferability scorers and showcase an opportunity to use transferability scorers to create ensembles of scorers, which we show consistently improves their results. We extensively evaluate 13 scorers from literature across 11 datasets, comprising generalist, fine-grained, and medical imaging datasets. We show that few scorers match the predictive performance of the simple raw metric of models on ImageNet, and that all predictors suffer on medical datasets.
transferability estimation, transfer learning, benchmark
225
ANALYZING CONSTRAINED LLM THROUGH PDFA-LEARNING
Matías Carrasco, Franz Mayr, Sergio Yovine, Johny Kidd, Martín Iturbide, Juan da Silva y Alejo Garat
Franz Mayr
We define a congruence that copes with null next-symbol probabilities that arise when the output of a language model is constrained by some means during text generation. We develop an algorithm for efficiently learning the quotient with respect to this congruence and evaluate it on case studies for analyzing statistical properties of LLM.
LLM, Analysis, Probabilistic Deterministic Finite Automata
226
Detection of Stress and State-Anxiety based on Physiological Signals
Matheus C. Lindino, Aurea S. Vargas and Anderson Rocha
Matheus Lindino
Stress and state-anxiety are natural defense mechanisms crucial for human adaptation and survival. However, untreated, they can progress into severe conditions like post-traumatic stress disorder, generalized anxiety disorder, and depression, as outlined in the DSM-5. Diagnosing these conditions often relies on professional interviews, which face challenges due to symptom overlap, periodic assessments, and the absence of continuous monitoring. To address these limitations, this study focuses on developing objective metrics for early detection and continuous monitoring of stress and state anxiety, aiming to prevent health deterioration and enhance treatment outcomes. The research employs machine-learning models to analyze and classify stress, and state anxiety by examining semantic differences and physiological impacts through signals like heart rate, galvanic skin response, and blood volume pressure.
Mental Health, Machine Learning and Physiological signals
227
A New Approach to Automatically Detect Trypanosoma cruzi in Blood Images Using Image Processing and Enhanced Data
Richard Sucuy Zhingre, Bertha Mazon-Olivo, Eduardo Tusa
Richard Sucuy Zhingre
Early diagnosis of Chagas disease remains a challenge due to its reliance on manual microscopic analysis, which is prone to human error. This study presents a machine learning approach for automating the detection of Trypanosoma cruzi in microscopic blood images using a Random Forest classifier and semantic segmentation. The methodology follows the CRISP-DM framework, integrating feature extraction and data augmentation to improve model performance. Preprocessing includes grayscale conversion, normalization, and contrast enhancement using CLAHE. Regions of interest (ROIs) are segmented using the Felzenszwalb method, ensuring precise parasite differentiation. Controlled rotation-based data augmentation increases dataset diversity and reduces overfitting. Experimental results show that the proposed model achieves 97.16% accuracy on the test set, surpassing previous studies by over five percentage points. Learning curve analysis confirms strong generalization capability. These findings highlight the potential of machine learning for automating Trypanosoma cruzi detection, providing a scalable and efficient tool for Chagas disease diagnosis. Future work aims to enhance dataset diversity, optimize feature selection, and explore hybrid models combining deep learning and traditional classifiers. Deploying this approach in real-world diagnostic systems could significantly improve early detection and treatment outcomes in endemic regions.
Trypanosoma cruzi, Semantic Segmentation, Random Forest
228
Machine Learning-Driven Prediction of Subject Phenotypes from EEG Spectral Signatures
Cecilia Jarne, Ben Griffin &Diego Vidaurre
Cecilia Jarne
Predicting subject traits from brain data is critical in neuroscience, with applications in clinical and cognitive research. While neuroimaging dominates prior work, electroencephalography (EEG)—a cost-effective, non-invasive modality—remains underexplored due to its complexity and reliance on manual feature extraction, which risks bias. We propose a data-driven approach using kernel methods to predict traits directly from EEG spectrograms, bypassing manual feature engineering. By reinterpreting each channel’s spectrogram as a probability distribution, we leverage kernel mean embedding regression (KMER) to rigorously model nonlinear relationships between spectral signatures and traits. We compare KMER to kernel ridge regression (KRR) and non-kernelized methods, demonstrating that kernel techniques improve prediction accuracy by capturing nonlinear dynamics inherent in EEG. Applying KMER to the multinational HarMNqEEG dataset, we predict biological age across diverse experimental setups, showcasing the method’s generalizability. Our results highlight the superiority of kernel methods in handling EEG complexity while maintaining computational rigor. This framework advances EEG-based trait prediction, offering a scalable, automated alternative to manual feature extraction and enabling broader applications in neuroscience and personalized medicine.
brain age, EEG, Kernel regression
229
Machine Learning in Microservices: A Multivocal literature review
Danelys Brito Gonzalez, Gastón Márquez, Julio Sotelo, Marcelo Visconti
Danelys Brito Gonzalez
The microservices architecture has gained considerable popularity over the past decade due to its ability to enhance the scalability, flexibility, and maintainability of complex applications. Simultaneously, Machine Learning has emerged as a powerful tool for the automation and optimization of various tasks, with applications in multiple domains, including the implementation and management of microservices. This document describes the design of a multivocal literature review on the application of Machine Learning techniques in microservices-related contexts. Through a comprehensive analysis of academic publications and relevant studies, predominant methodologies, tools, and approaches in this emerging field are identified and categorized. The study highlights current trends, challenges encountered, and future opportunities, providing a comprehensive guide for researchers and professionals interested in optimizing software architecture through machine learning techniques.
Microservices, Machine Learning, Multivocal literature review
230
Modeling Behavioral Dynamics: Machine Learning for Scalable Personalized E-commerce Recommendations
Rodrigo Laguna, Pablo Rodriguez Zivic, Jorge Sanchez
Rodrigo Laguna
Personalized recommendations are essential for e-commerce success, but delivering them effectively at scale presents several challenges. This poster focuses on sequential recommendations, as user actions within the system can be modeled as a sequence of events. This approach draws parallels with language modeling and gives rise to the development of large recommendation models (LRMs). Since user actions depend on the specific system, relying on pre-trained solutions is not feasible, necessitating the creation of context-specific LRMs.Techniques and architectures similar to those used in large language models (LLMs) are applied, along with a study of scaling laws and optimal compute allocation. It is important to note that recommendation tokens differ from language tokens, and the variety of event types adds further complexity to the modeling process.This poster outlines the challenges encountered and lessons learned, contributing to a broader understanding of personalized e-commerce and enhancing user experiences in a competitive marketplace.
Sequential Recommendation, Large Recommendation Models (LRMs), E-commerce Personalization
231
TiEBe: A Benchmark for Assessing the Current Knowledge of Large Language Models
Thales Sales Almeida, Giovana Kerche Bonás, João Guilherme Alves Santos, Hugo Abonizio, and Rodrigo Nogueira
Giovana Bonás
In a rapidly evolving knowledge landscape and the increasing adoption of large language models, a need has emerged to keep these models continuously updated with current events. While existing benchmarks evaluate general factual recall, they often overlook two critical aspects: the ability of models to integrate evolving knowledge through continual learning and the significant regional disparities in their performance. To address these gaps, we introduce the Timely Events Benchmark (TiEBe), a dataset containing over 11,000 question–answer pairs focused on globally and regionally significant events. TiEBe leverages structured retrospective data from Wikipedia, enabling continuous updates to assess LLMs' knowledge of evolving global affairs and their understanding of events across different regions. Our benchmark demonstrates that LLMs exhibit substantial geographic disparities in factual recall, emphasizing the need for more balanced global knowledge representation. Furthermore, TiEBe serves as a tool for evaluating continual learning strategies, providing insights into models' ability to acquire new information without forgetting past knowledge.
Benchmark, Factual recall, Significant events
232
La Leaderboard: A Large Language Model Leaderboard for Spanish Varieties and Languages of Spain and Latin America
María Grandury, Javier Aula-Blasco, Júlia Falcão, Clémentine Fourrier, Miguel González Saiz, Gonzalo Martínez, Gonzalo Santamaría, Rodrigo Agerri, Nuria Aldama, Sebastian Cifuentes, Javier Conde, Marta Guerrero Nieto, Guido Ivetta, Natàlia López Fuertes, Flor Miriam Plaza-del-Arco, María-Teresa Martín-Valdivia, Helena Montoro Zamorano, Carmen Muñoz Sanz, Pedro Reviriego, Leire Rosado Plaza, Alejandro Vaca Serrano, Jorge Vallego, Estrella Vallecillo-Rodríguez, Irune Zubiaga
María Grandury
Leaderboards are the most widespread and convenient way to measure the performance evolution of Large Language Models (LLMs). To motivate the development of LLMs that represent the linguistic and cultural diversity of the Spanish-speaking community, we present La Leaderboard, the first open-source leaderboard to evaluate generative LLMs in languages and language varieties of Spain and Latin America. La Leaderboard is a community-driven project that aims to establish an evaluation standard for everyone interested in developing LLMs for the Spanish-speaking community. This initial version combines 66 datasets in Catalan, Basque, Galician, and different Spanish varieties, showcasing the evaluation results of 40 models. To encourage community-driven development of leaderboards in other languages, we explain our methodology, including guidance on selecting the most suitable evaluation setup for each downstream task. In particular, we provide a rationale for using fewer few-shot examples than typically found in the literature, aiming to reduce environmental impact and facilitate access to reproducible results for a broader research community.
LLM Evaluation, Leaderboard, Low-Resource NLP
233
Exploration of Transformer-Based Architectures for Generative Models of Eye Movement Behavior
Christ Devia
Christ Devia
In the present study, we explore the efficacy of a transformer-based architecture in the generation of synthetic eye movement data. Our method involved training a compact GPT architecture with real eye scanning data obtained from human subjects. The development of this model hinged on the unique benefits offered by the transformer architecture in handling sequential content. Taking into consideration previous research findings, we conceptualized eye behavior as a syntactic entity. We designed a parser that translated the parameters of eye behavior into a textual representation. The model was subsequently trained using this textual representation of behavior.The performance of the resulting model was evaluated mainly as the quality of the generated data, which was assessed by measuring the similarity between the statistical features of the generated data and the behavior of real subjects. In this context, we also explored the impact of context size on the generated data. Our findings suggest that generative models of eye movements have the potential to significantly impact a variety of disciplines, ranging from behavioral neuroscience to robotic vision.
Eye-movements; GPT; Synthetic data
234
Exploring political alignment in LLMs
Mateo Servent
Mateo Servent
LLMs, Alignment, Politics
235
Temporal correspondence of visual processing of rapid stimuli between the human brain and artificial neural network architectures
Eric Lützow Holm, Giovanni Marraffini, Enzo Tagliazucchi
Eric Lützow Holm
The visual cortex processes information hierarchically, from low-level features to complex patterns that enable object categorization. Similarly, in the most successful artificial models for object recognition, images are processed through multiple layers of artificial neural networks trained to determine the corresponding class. The goal of this work is to compare these models in terms of their temporal correspondence with EEG data recorded during visual perception tasks to determine whether the similarity between both systems depends on generic aspects or if it is influenced by the specific computations of each model. Using public EEG data from tasks involving rapid visual stimuli and the architectures AlexNet, MoCo, ResNet-50, VGG-19, and ViT, we found that the initial layers correlate better with activity evoked in early stages and low-level image statistic features, while the later layers correlate better with late components and semantic information. These results suggest a universal parallelism between human processing and that of artificial systems for the recognition of rapid visual stimuli.
EEG, CNN, vision
236
Scaling Laws for domain specialization (I would love to also give a speech about the overall work that my group is doing, if a slot is available)
Roseval Malaquias Junior, Ramon Pires, Thales Sales Almeida, Kenzo Sakiyama, Roseli Romero, Rodrigo Nogueira
Rodrigo Nogueira
Scaling laws for language models have often focused on finding the compute-optimal model size and token count for training from scratch. However, achieving this optimal balance requires significant compute resources due to the extensive data demands when training models from randomly-initialized weights. Continual pre-training offers a cost-effective alternative, leveraging the compute investment from pre-trained models to incorporate new knowledge without requiring extensive new data. Recent findings suggest that data quality influences constants in scaling laws, thereby altering the optimal parameter-token allocation ratio. Building on this insight, we investigate the interplay between domain specialization and model size during continual pre-training under compute-constrained scenarios. Our goal is to identify a compute-efficient training regime for this scenario and, potentially, detect patterns in this interplay that can be generalized across different model sizes and domains. To compare general and specialized training, we filtered a web-based dataset to extract legal domain data. We pre-trained models with 1.5B, 3B, 7B and 14B parameters on both the unfiltered and filtered datasets, then evaluated their performance on legal exams. Results show that, as model size increases, the compute-effectiveness gap between specialized and general models widens
Scaling Laws, Domain Specialization, LLMs
237
Modelos de Machine Learning para Predecir Ideación Suicida: Un Análisis de Factores Psicológicos y Demográficos en Estudiantes Universitarios"
Fernanda Rubio
Fernanda Rubio
Se implementan y evalúan 5 modelos de machine learning para predecir la ideación suicida en estudiantes universitarios, utilizando datos psicológicos y demográficos en sus versiones numéricas y categóricas. Los modelos utilizados incluyen Regresión Logística, Random Forest, SVM, Redes Neuronales y XGBoost, aplicados con y sin técnicas de reducción de características (RFECV) y balanceo de clases. Los principales resultados indican que los modelos de Regresión Logística optimizada con datos numéricos y XGBoost con RFECV fueron los más efectivos en términos de equilibrar las métricas de recall y accuracy. El análisis de importancia de características destaca la relevancia de variables como la depresión, la desesperanza, la soledad, un diagnóstico de neurodivergencia y el género en la predicción de riesgo suicida.
Machine learning, Clasificación, Salud mental
238
Semi Supervised Multi-Task Learning for Explainable Quality Assessment of Fundus Images
Lucas Gabriel Telesco, Ignacio Larrabide and José Ignacio Orlando
Lucas Telesco
Retinal image quality assessment (RIQA) tools play a vital role in screening platforms for the diagnosis of eye diseases. However, current methods primarily focus on classifying overall image quality, offering little feedback on acquisition defects or explainable outputs to assist technicians in improving image capture. To address these limitations, we propose a semi-supervised, multi-task learning approach that reduces labeling costs while enhancing both performance and explainability. Our method leverages a Teacher model pre-trained on a small labeled dataset to generate annotations for an unlabeled dataset. These weak annotations, combined with ground-truth quality labels, are used to train a multi-task model capable of evaluating overall image quality and identifying specific acquisition defects simultaneously. Experiments on the EyeQ and DeepDRiD benchmarks demonstrate that our approach improves F1-scores for quality assessment compared to single-task models (0.875 vs. 0.863 on EyeQ; 0.778 vs. 0.763 on DeepDRiD). Additionally, our multi-task model produces GradCAM visualizations that are more explainable, with better ROAD metrics compared to single-task. Our results also show that weakly supervised annotations are as reliable as expert-level labels, confirming their validity. All annotations will be published to promote further advancements.
Retinal imaging, Semi supervised, Multi-task learning
239
Quantifying Language Complexity
Felipe R. Serras, Marcelo Finger
Felipe Ribas Serras
Quantifying and measuring language complexity remains an open problem in classical linguistics, crucial for understanding the mechanisms underlying human language and its potential for variation. Additionally, it has proven useful for enhancing language technologies. This study investigates potentially universal methods for assessing linguistic complexity using information theory and data compression techniques, presenting key findings and unresolved questions.
Natural Language Processing, Computational Typology, Data Compression
240
Integrative multi-omics approaches for rare diseases diagnosis
Camila Simoes, Hugo Naya, Lucía Spangenberg
Camila Simoes
Rare diseases (RDs) affect between 3.5% and 5.9% of the global population. Their low prevalence, heterogeneity, and complex symptoms make diagnosis particularly challenging. It is estimated that 80% of RDs have a genetic origin, highlighting the importance of identifying their molecular basis for accurate diagnosis. Next-generation sequencing (NGS) has significantly improved RD diagnosis; however, approximately 50% of patients remain undiagnosed after applying whole exome sequencing (WES) or whole genome sequencing (WGS). In these cases, multi-omic approaches are needed, integrating data from different biological fields such as transcriptomics and proteomics. However, integrating multi-omic data poses challenges such as noisy and missing data, high dimensionality, and batch effects. Additionally, the Uruguayan population is admixed and underrepresented in genomic databases, which may impact diagnostic accuracy. Developing integrative approaches that account for these factors can enhance disease diagnosis and improve understanding of molecular mechanisms in admixed populations. In this context, we present ongoing advancements in multi-omic data integration using machine learning strategies for rare disease diagnosis, within the Bioinformatics Unit at the Institut Pasteur de Montevideo and UdelaR.
Multi-omics, medical genomics, bioinformatics
241
AI Ethics and Education
Javiera Mery (Javiera Ignacia Gonzalez Mery)
Javiera Ignacia Gonzalez Mery
This study is centered in the intersection of Artificial Intelligence (AI) ethics, and education development, approached through a comparative and interdisciplinary lens. Currently exists a growing interest about the ethical implications of emerging technologies, focusing particularly on the anthropological and philosophical dimensions of AI. This study contributes to enhancing educational development in Latin America, with a special emphasis on the Chile-Peru-Brazil axis, fostering international cooperation to address shared challenges and opportunities. This includes the adoption, regulation, technological transfer, and application of AI, particularly in the context of education policy and ethical dimensions. A key focus of this study is a comparative analysis of Brazil and Chile, examining how their distinct governance structures (a federal system in Brazil versus a unitary system in Chile) shape AI Ethics in education policy frameworks. Through comparative analysis, the aim is to better understand and identify the implications of these systems on education reform, equity, inclusivity, development and the integration of emerging technologies in order to educate for an AI-driven world, contributing to a deeper understanding of how AI Ethics can transform education while fostering regional and international collaboration.
AI Ethics, Education, Development
242
Asymmetric Evaluation for Document Classification in Industry
Karen Tovar Parra
Karen Tovar Parra
Traditional evaluation metrics for multi-label document classification assume symmetric importance across labels, which does not reflect real-world industry needs. This work introduces an asymmetric evaluation approach that considers label relevance, class imbalance, and reasoning quality. Standard metrics such as Precision, Recall, F1-score, and Hamming Loss fail to capture the nuanced importance of labels in industry applications. We propose a custom asymmetric metric that assigns higher importance to directly relevant labels, adjusts for class imbalance, and optionally evaluates reasoning quality in LLM-based classification systems. The metric incorporates asymmetric focusing on difficult examples and label smoothing using co-occurrence relationships. Our approach is designed to improve performance evaluation in applications where document categorization must differentiate between essential and secondary labels. We also discuss the feasibility of deriving predicted probabilities from Retrieval-Augmented Generation (RAG) models or ground-truth datasets. This work presents a benchmark pipeline that integrates the proposed asymmetric metric, offering a more realistic evaluation framework for industry-scale document classification tasks.
Asymmetric Evaluation, Document Classification, Industry Benchmarking
243
PAYADOR: Grounding Large Language Models on Structured Representations for Role-playing Games 🎲
Santiago Góngora, Luis Chiruzzo, Gonzalo Méndez
Santiago Góngora
Tabletop Role-playing Games (TTRPGs) are a type of experience where players interact through dialogue, acting as characters exploring a fictional world.All players have a voice, and they can freely act to give life to their characters. That is the reason why TTRPGs are considered frameworks for collaborative storytelling.Among all those players there is a special one, the Game Master (GM), who is in charge of orchestrating the game, narrating the locations the players will explore and designing the challenges they will face there.TTRPGs are very complex games, and several attempts have been made to build computer models of them.One of the main problems is how to update the fictional world after the actions freely taken by the players, in order to keep it consistent and, as a consequence, keep the story coherent.In this poster we present PAYADOR, a strategy to face the world-update problem for GM models.Instead of the classic approach of pre-programming every action that a character or an item can do, we propose to pre-program how the fictional world can change, where an LLM determines which world-transforming actions must be taken after the player’s actions.
Interactive Storytelling, Grounding Large Language Models, Computational Creativity
244
Observatorio Digital de las Mujeres Latinoamericanas - Digital Observatory of Latin American Women
Alejandra J. Josiowicz, Genoveva Vargas-Solar
Alejandra Josiowicz
My project examines sociocultural meanings around Latin American Women Intellectuals, developing datastets from Wikipedia, as well as computational methodologies to process and analyze the data and metadata. Recent studies have critically examined the global, gender, and language inequalities that permeate Wikipedia. These studies point to the hierarchical and exclusionary structure of the platform, both in terms of topics and biographies as well as editorial culture. The privileged position of Wikipedia in the training and development of Language Models makes it an important space to map and reflect on the place of women in the processes of knowledge creation in and on Latin America. This fact only underscores the importance of mapping how this and other platforms considered "high quality" reproduce stereotypes on Latin American women intellectuals. The project seeks to explore 1) the ways in which Language Models amplify existing biases on discourses on Latin American women intellectuals, as seen on Wikipedia 2) the use of Machine Learning in the Wikipedia platform for detecting vandalism towards discourses on Latin American Women 3) the possibility of biases in Machine Learning algorithms that classify articles on Latin American women intellectuals as lesser quality.
Latin America, Women Intellectuals, Science and Technology Studies
245
Tierra de poetas: A Chilean Spanish First-Language Dataset
Sofía Correa Busquets & Valentina Córdova Véliz
Sofía Correa Busquets & Valentina Córdova Véliz
Beyond other quality deficits of K-12 education in the global south, Chile stands out for inequity between its public, subsidized and private education. Added to a profound teacher shortage, any leveling improvements require great scalability, calling for effective educational technology development. We present a dataset of every policy document concerning Chilean public first-language (L1) education for 2024, to provide the necessary domain-specific Chilean Spanish data in plain text. These comprise: curricular bases aimed at education professionals; L1 official student textbooks for first through twelfth grade; and their corresponding teacher guidebooks, which suggest best pedagogical practices for guiding the class using the textbooks. The resulting SQL database formats 25MB of raw text from 36 PDFs into around 11500 rows, allowing to structurally relate every page of student-aimed content to its corresponding page for teacher guidance. Nevertheless, some errors in text order appear, due to the lack of research in transforming textbooks’ multimodal content to plain text. Possible applications for this dataset span large-scale text analytics of pedagogical content to inform policymakers, ease of copy-and-paste format for teachers to semi-automate administrative tasks, and use as a knowledge base for research in Chilean educational technology.
PDF mining, educational technology, Chilean Spanish data
301
Data Distributional Properties as Inductive Bias for Systematic Generalization
Felipe del Río, Alain Raymond-Sáez, Daniel Florea, Rodrigo Toro Icarte, Julio Hurtado, Cristián Buc and Álvaro Soto
Felipe del Río
DNNs struggle at systematic generalization (SG). Several studies have evaluated the possibility to promote SG through different methodologies. Few have focused on the role of training data properties in promoting SG. Here, we investigate the impact of certain data distributional properties, as inductive biases for the SG ability of a multi-modal LM. To this end, we study three different properties. First, data diversity, the number of possible values a latent property may take. Second, burstiness, where we probabilistically restrict the number of possible values of latent factors on particular inputs during training. Third, latent intervention, where a particular latent factor is altered randomly during training. We find that all three factors significantly enhance SG, with diversity contributing an 89% absolute increase in accuracy in the most affected property. We test various hypotheses to understand why these properties promote SG. Finally, we find that Normalized Mutual Information (NMI) between latent attributes is strongly predictive of out-of-distribution generalization. Also, a mechanism by which lower NMI induces SG is in the geometry of representations. In particular, we find that NMI induces more parallelism in neural representations of the model, a property related to the capacity of reasoning by analogy.
302
Smart Lateral Flow Test Analysis with AI for Agriculture
Walter Mayor-Toro
Walter Mayor
Lateral Flow Tests (LFTs) are widely used for rapid diagnostics due to their affordability and ease of use. However, manual interpretation of LFTs can be subjective and error-prone, particularly in field environments like agriculture, where varying lighting conditions and operator inconsistencies can affect accuracy. To address this challenge, we propose an automated pipeline that leverages computer vision and machine learning techniques for robust, objective LFT analysis. Our method consists of two stages: membrane segmentation and line intensity detection. The segmentation stage employs a model to accurately isolate and align the membrane, correcting rotational misalignments to standardize input data. Subsequently, line intensity detection is performed using OpenCV to quantify line visibility against background noise. This quantitative data is used to classify test results as positive, negative, or invalid with high reliability. The pipeline is optimized for deployment on portable devices using ONNX, making it suitable for real-time agricultural diagnostics. Experimental results demonstrate significant improvements in consistency and accuracy over traditional manual methods, providing a scalable solution for automated field-based testing.
Agriculture, Lateral Flow Test, rapid diagnostics
303
Wireless Link Scheduling Algorithm using State Augmentation.
Romina Garcia, Zhiyang Wang, Navid NaderiAlizadeh, Alejandro Ribeiro.
Romina García
In recent years, there have been growing demands for higher data rates and an increasing number of connected devices in wireless networks, leading to a paradigm shift in network management. Efficient resource allocation is now crucial, requiring fairness among users and high success rates. In this context, we address the challenge of transmission scheduling in wireless networks with link interference. We propose an algorithm that combines state augmentation techniques and a Graph Neural Network to optimize resource allocation. This approach maximizes the network's non-conflicting performance while ensuring that all links meet their minimum transmission requirements. The optimization is done for the average of the number of successful transmissions completed in a series of timesteps.
resource allocation, graph neural networks, state agumentation
304
Symbolic Regression and LLM Synergy: Enhancing Explainability in Genomic Predictions
José Vásquez-Bastías, Luis Valenzuela, Nayat Sánchez-Pi, Luis Martí.
José Vásquez-Bastías
Marine microbiome communities are essential for converting CO2 into organic matter and O2. They support marine food webs and drive the biological carbon pump that sequesters CO2 from the surface to the deep ocean. In previous work, approximately 36,000 equations were derived via symbolic regression to capture the relationships among metagenomes, metatranscriptomes, taxonomy, and environmental variables using the Ocean Microbial Reference Gene Catalog (47 million genes annotated into 9024 KEGG functions) generated by Tara Océan.In the present work, we aim to automate the interpretation of these equations using large language models (LLMs). Specifically, we enhance their explainability by leveraging pre-trained LLMs—including DeepSeek-Math-7B, Qwen2.5-Math-7B, and GPT2, and RoBeRTA as baselines—to generate embeddings for the equations. We then apply dimensionality reduction to these embeddings to identify clusters in the latent space. Finally, by providing a comprehensive glossary of variables, we prompted the models to reason about the mathematical structure of each equation relative to its target, comparing their interpretations with those of a domain expert.Our findings demonstrate that SOTA LLMs capture robust mathematical reasoning and biologically meaningful patterns, underscoring their potential for interpreting high-throughput symbolic regression outputs.
Large language models, symbolic regression, bioinformatics
305
EGNN-based Topology Control in Wireless Mobile Infrastructure on Demand with Shared Access Restrictions
Mariana del Castillo, Alejandro Ribeiro, Federico Larroca
Mariana del Castillo
Mobile Infrastructure on Demand (MIoD) deploys a mobile ad-hoc network to support communication for a group of mobile agents. This study optimizes the placement of network agents while considering the shared nature of the wireless medium—an aspect often overlooked in prior approaches focused on graph connectivity or direct communication metrics.We introduce an optimization model that incorporates shared access restrictions, capturing key wireless communication constraints. To approximate the dependency of communication indicators on node positions, we leverage E(n)-Equivariant Graph Neural Networks (EGNNs), which naturally respect translation and rotation symmetries. Using gradient ascent, we then optimize network agent positions.Our approach outperforms traditional methods, achieving better topology control as measured by a higher figure of merit. The key contributions include integrating shared access restrictions into the optimization framework and proposing an EGNN-based Black Box Optimization method for MIoD topology control.
Black box optimization, Graph Neural Networks, Multi-agent System
306
Diversa: Designing Inclusive AI for Latin America and the common good
Diana Mosquera, Francisco Gallegos
Diana Mosquera
Diversa is an AI and data studio dedicated to designing human-centered and environmentally-focused AI solutions that align with the needs, contexts, and rights of people and communities. Our approach integrates a critical lens to continuously evaluate and innovate AI data and processes, incorporating principles of social justice and ethical responsibility at every stage of development. Diversa's interdisciplinary collaborations with organizations and universities address key challenges, such as urbanism from a feminist perspective, migration, or natural resource governance, among others. By prioritizing equity and inclusion, Diversa leverages AI as a transformative tool for justice and sustainable development, ensuring that technological innovations are attuned to the lived realities and aspirations of the communities they are intended to serve.As an active member of the A+ Alliance for Inclusive Algorithms and the Global Feminist AI Research Network (Latin American and Caribbean node), Diversa emphasizes the materiality of artificial intelligence. We highlight the dependence of AI systems on energy, natural resources, labor and data, advocating for a more responsible and informed understanding of their impacts.This poster will show a summary of all the projects implemented at Diversa, addressing how to implement AI from a responsible and community-based perspective.
Co-design with communities, Artificial Intelligence, Responsible innovation
307
Multidimensional Poverty Targeting
Ignacio Girela & Eric Koplin
Ignacio Girela
Poverty is widely acknowledged as a multifaceted phenomenon, demanding policies that reflect its complex nature. This research proposes a novel approach to poverty analysis and policy design using Discrete Markov Networks. We argue that understanding the conditional dependencies between multidimensional poverty indicators is crucial for effective intervention. Our methodology employs a Markov network estimator specifically designed to handle structural zeros, which arise when the positivity condition is violated. This violation occurs when certain combinations of poverty indicators are never observed in the data. By explicitly accounting for these structural zeros, our estimator provides a more accurate representation of the underlying dependency structure. This learned network of conditional independencies serves as the foundation for identifying the most effective poverty reduction policies. We demonstrate how this approach can be used to prioritize interventions and target resources more efficiently, ultimately contributing to a more nuanced and impactful strategy for poverty alleviation.
Multidimensional Poverty, Markov Networks, Reinforcement Learning
308
Neural Conjugate Flows: Higher-Performance Neural Differential Equations.
Arthur Bizzi
Arthur Bizzi
Neural Differential Equations (Neural ODEs) offer a way to construct deep networks with continuous, infinite depth. However, these models are currently too computationally expensive to be used in applications. We present an alternative, called Neural Conjugate Flows, which uses concepts in dynamical systems to produce Neural ODEs that are up to two orders of magnitude faster and are equipped with strong topological structure.
Neural ODEs, Neural Conjugate Flows, Physics-Informed Neural Networks
309
Efficient Image Editing in Diffusion Models with Compressed Latent Representations
José Eduardo Ochoa Luna, María Graciel Cruz Cáceres
María Graciel Cruz Cáceres
Image editing aims to generate images based on a guidance text and a target text. However, current methods using diffusion models face efficiency challenges. High time consumption and difficulty in preserving the original image structure. The objective of this paper is to develop an image editing technique that reduces editing time and preserves the original structure. This technique combines two state-of-the-art models based on diffusion models. We proposed a novel technique that combines the Würsten model and the PnP-Diffusion technique. Würsten generates images guided by target texts using compact image representations. PnP-Diffusion injects features in the generation process. This allowed us to maintain the original structure while representing the target text. The proposed method achieved an Fourteen-times reduction in editing time. Our efficient image editing technique demonstrated significant improvements in speed and resource usage. Also maintaining image high image quality. This approach can potentially democratize access to generative AI models in image editing. It does so by making them more efficient.
diffusion, image edition, text-image
310
Brain Computer Interfaces and Algorithmic Fairness
Bruno J. Zorzet, Victoria Peterson, Diego H. Milone, and Rodrigo Echeveste
Bruno Jose Zorzet
Brain Computer Interfaces (BCI) are systems that allow users to control external devices by modulating their brain activity. Electroencephalography (EEG) is the most common signal used, due to its practicability and high temporal resolution. Motor Imagery (MI) based BCIs are promising for stroke rehabilitation. In this process, individuals imagine executing a movement, and then the signal is decoded into commands to control an external device. Due to the complexity of the EEG signals, increasing availability of datasets, and advances in artificial neural networks, the BCI community is using more and more Deep Learning (DL) models to construct the brain signal decoders. However, it is interesting to study in the context of MI-BCI whether DL models are also susceptible to biases which may lead to disparate performances across subpopulations. In this research, we are interested in understanding how DL algorithms learn inner characteristics from the data related with the ability of subjects to self-regulate their brain activity together with the information of protected attributes. Understanding which variables influence the performance on MI-BCI based on deep learning is important for the development of not only more powerful models but also more fair systems.
Fairness, Brain Computer Interfaces, Deep Learning
311
BNCT and the SIRENs: dose map super resolution using Implicit Neural Representations
Guillermo Marzik. María Eugenia Capoulat, Andrés Kreiner, Daniel Minsky
Guillermo Marzik
A precise treatment plan is crucial for the success of Boron Neutron Capture Therapy. For this purpose, dose distribution maps are simulated using a patient's CT scan and the configuration of the proposed neutron source. However, to reduce computational costs, these dose maps are generated at a much lower resolution than the original CT scan, limiting physicians' ability to assess the treatment's effectiveness. In this work, we propose a super-resolution model based on implicit neural representations to enhance dose distribution maps. Our approach aims to improve the level of detail in dose maps, enabling better tissue-specific analysis. The model was trained on 3D dose distribution maps with a voxel size of 1 cm³ and evaluated on maps with a voxel size of 9 mm³. Four metrics were used to assess model performance: mean squared error, structural similarity index, peak signal-to-noise ratio, and the percentage of voxels with acceptable error. The impact of the loss function, network architecture, and sinusoidal activation function frequencies, comparing each variant against a baseline linear interpolation model, were analyzed. Experimental results show that the proposed model effectively enhances dose map resolution, consistently outperforming the baseline model across all evaluated metrics.
Boron Neutron Capture Therapy, Super resolution, Implicit Neural Representations
312
Causal Discovery using Bayesian Structure Learning and LLMs
Bruna Bazaluk, Benjie Wang, Denis D. Mauá, Flávio Soares C. da Silva
Bruna Bazaluk M V
Researchers have been using Large Language Models (LLMs) in many different tasks, including reasoning, prediction, and causality, the latter being an important field in Sciences, which includes understanding causal relationships between variables in a system rather than correlations. In this work, we use Bayesian Structure Learning (BSL) with the help of LLMs to do Causal Discovery. In our experiments, we concluded that using DiBS (Differentiable Bayesian Structure Learning), one of the many BSL algorithms, with an LLM to define the probabilities of each edge of the causal graph as the prior, yielded better results than using other common priors.
causality, llm, nlp
313
Predictive Modeling for Fetal Health: A Comparative Study of PCA, LDA and KPCA for Dimensionality Reduction
Ariana Deyaneira Jiménez-narváez ,victor David Casa Vaca ,jonathan Javier Loor-duque ,isidro Rafael Amaro Martín ,iván Galo Reyes-chacón ,paulina Vizcaíno ,manuel Eugenio Morocho-cayamcela
Ariana Jiménez
Pregnancy complications significantly impact maternal and fetal health, necessitating timelyand accurate diagnostic methods to ensure life-saving interventions. Traditional manual analysis of cardiotocography (CTG) tests, a widely used technique for fetal monitoring, is labor-intensive and subject to variability. This study explores the application of dimensionality reduction techniques principal component analysis, linear discriminant analysis, and kernel principal component analysis—to improve the performanceof machine learning (ML) models in predicting fetal health based on CTG data. Utilizing a dataset containing 2126 records, we aim to reduce the feature space while preserving essential information, enhancing classification accuracy and efficiency. We deploy several ML classifiers, including logistic regression, random forests, XGBoost, support vector machines, and k-nearest neighbors. The results demonstrate that PCA significantly enhances classification performance by efficiently capturing variance in the data. These findings emphasize the critical role of feature selection and dimensionality reduction in developing robust ML models for fetal health assessment.
Cardiotocography (CTG), Dimensionality Reduction, Machine Learning (ML)
314
Clasificador Inteligente de Imágenes de Cáncer de Mama utilizando Redes Convolucionales y Ant Lion Optimizer
Reyna Der Boghosian, Ignacio Bosch
Ignacio Bosch
Las imágenes de ultrasonido son fundamentales en el diagnóstico del cáncer de mama ya que el análisis de los tejidos permite evaluar su estado fisiopatológico. Este es un proceso que requiere la intervención de especialistas. Los avances en informática permiten optimizar este proceso mediante sistemas inteligentes que automatizan tareas, reducen tiempos y mejoran la exactitud de los resultados. Este trabajo propone diseñar e implementar un sistema inteligente para la clasificación de imágenes de cáncer de mama utilizando redes neuronales convolucionales optimizadas mediante algoritmos metaheurísticos. Se implementaron dos arquitecturas convolucionales: estándar CNN y ResNet50 utilizando como optimizador la metaheurística Ant Lion Optimizer. Esta metaheurística mejora la exactitud de CNN de 56.57% a 81.57% en la clasificación, y en ResNet50 de 86.84% a 92%. Los resultados demuestran la eficacia de combinar arquitecturas de aprendizaje profundo con algoritmos metaheurísticos para la clasificación de imágenes de mama.
Metaheuristics, Convolution, Breast Cancer
315
AI-DRIVEN 11-miRNA PANEL FOR PROGNOSTIC PREDICTION IN OVARIAN CANCER
Cristiane Esteves Teixeira, Nayara Tessarollo, Alessandra Serain, Alexandre Dias Porto Chiavegatto Filho and Mariana Boroni.
Cristiane Teixeira
Ovarian cancer (OC), the most deadly gynecological cancer, receives its diagnosis at an advanced stage mainly due to vague symptoms that hinder early detection. Survival rates decline at these points, underscoring the necessity of precise prognostic instruments to direct therapeutic approaches. Currently, few clinical indicators are available for OC prognosis. Biomarkers supporting clinical decision-making can be found by combining artificial intelligence with omics data. Among omics data, miRNAs are easily detectable and important gene regulators implicated in tumor growth. This research aimed to find new biomarkers linked to OC outcomes and build a miRNA-based prognostic predictor. Patients with OC from The Cancer Genome Atlas were categorized into poor prognosis (survival <3 years, deceased) and good prognosis (survival ≥3 years). Using FCBF, Cox regression and LASSO, 47 miRNAs were selected as relevant. A Random Forest model trained on a final panel of 11 miRNAs achieved excellent performance: AUC = 0.856, sensitivity = 0.780, and F1-score = 0.769. Validation in clinics using an independent cohort achieved 62% accuracy (n=26). This 11-miRNA panel is a reliable prognostic tool. A patent has been filled and a health-tech startup is being developed to translate these findings into clinical practice.
ovarian cancer, prognosis, machine learning
316
Fairness of Deep Ensembles: On the interplay between per-group task difficulty and under-representation
Estanislao Claucich, Sara Hooker, Diego H. Milone, Enzo Ferrante, Rodrigo Echeveste
Estanislao Claucich
Ensembling is commonly regarded as an effective way to improve the general performance of models in machine learning, while also increasing the robustness of predictions. Recent work has shown how in multi-class problems simple homogeneous ensembles may favor performance of the worst-performing target classes. While homogeneous ensembles are simpler to implement in practice, it is not yet clear whether their benefits translate to groups defined not in terms of their target class, but in terms of protected attributes. In this work we show how this simple and straightforward method is indeed able to mitigate disparities, particularly benefiting under-performing subgroups. Interestingly, this can be achieved without sacrificing overall performance, which is a common trade-off observed in bias mitigation strategies. Moreover, we analyzed the interplay between two factors which may result in biases: sub-group under-representation and the inherent difficulty of the task for each group. These results revealed that having balanced datasets may be suboptimal if the task difficulty varies between subgroups. Indeed, we found that a perfectly balanced dataset may hurt both the overall performance and the gap between groups. This highlights the importance of considering the interaction between multiple forces at play in fairness.
fairness, ensembles, difficulty
317
Monitoreo de Ciervos en Peligro con Deep Learning
Agustín Roca, Gabriel Torre, Juan I. Giribet, Gastón Castro, Leonardo Colombo, Ignacio Mas, Javier Pereira
Agustín Roca
Este trabajo analiza el uso de Vehículos Aéreos No Tripulados (UAVs) y aprendizaje profundo para detectar ciervos en peligro de extinción en sus hábitats naturales. Los métodos tradicionales de identificación requieren mano de obra especializada, lo cual es costoso y lento, por lo que se buscan soluciones más eficientes. Utilizando imágenes aéreas de alta resolución, se aplican técnicas avanzadas de visión por computadora para automatizar la identificación de ciervos en dos proyectos en Buenos Aires, Argentina. El primero trabaja con el ciervo de los pantanos en el Delta del Paraná, y el segundo, WiMoBo, con el ciervo de las Pampas en el Parque Nacional Campos del Tuyú. Se entrenó un modelo de detección de objetos, YOLO, con datos obtenidos de imágenes capturadas por UAVs. Los resultados muestran que el algoritmo identifica con alta precisión al ciervo de los pantanos y da indicios de su aplicación al ciervo de las Pampas, aunque con algunas limitaciones. Este trabajo apoya la conservación y destaca el potencial de combinar IA y tecnología UAVs para mejorar el monitoreo y gestión de la fauna.
Wildlife detection, YOLO, UAV
318
Neural Machine Translator for Native Language Aymara
Honorio Apaza, Allison I. Reynoso
HONORIO APAZA
This research develops and evaluates neural machine translation models for translating from Spanish to Aymara, utilizing Seq2Seq with attention and Transformer architectures. The main objective is to improve translation quality in low-resource languages, such as Aymara, and promote access to information and digital services for native communities. Experimental results demonstrate that the Transformer model outperforms the Seq2Seq model in several key metrics. The masked accuracy for the Transformer model is 0.87 compared to 0.68 for Seq2Seq, while the loss is significantly lower at 0.87 versus 1.44. Similarly, evaluation metrics such as BLEU (0.042 vs. 0.031), ROUGE-1 (0.40 vs. 0.29), ROUGE-2 (0.20 vs. 0.11), ROUGE-L (0.39 vs. 0.29), and METEOR (0.40 vs. 0.29) consistently highlight the superior performance of the Transformer. These findings underscore the effectiveness of the Transformer model in improving translation accuracy and efficiency for low-resource languages like Aymara.
NLP, NMT, seq2seq, tranformers, aymara, native language, machine translator
319
An automation bias study for ischemic stroke segmentation in Diffusion-weighted MRI studies: Implications and Insights
Santiago Gómez, Oscar Ramirez, Daniel Mantilla, Ana Araujo, Nelson Escobar, Sofia Velasco, Laura Campaña Perilla, Diego Rosales, Fabio Martínez
Santiago Gómez
Stroke is the second leading cause of mortality and disability in the world. Ischemic stroke is the predominant stroke type, caused by the occlusion of blood vessels. Ischemic lesion segmentation using diffusion-weighted MRI, considered the gold standard for infarct characterization, is essential for guiding clinical interventions and predicting patient outcomes. However, this process is expensive, time-consuming, and susceptible to observational bias from experts. Multiple artificial intelligence strategies have been proposed to support physicians in the lesion delineation process. While promising for protocol optimization, these approaches may introduce biases in lesion characterization, increasing false findings and raising concerns about their efficacy. This study reports preliminary findings about the implications of supporting expert delineations using annotations generated by a multimodal AI strategy. A comprehensive analysis was conducted with 100 DWI studies, to examine the differences between initiating delineations from an initial mask versus starting from scratch. A high similarity in Dice and volume differences in both assisted groups suggests that AI could be an effective tool for characterizing stroke lesions.
Ischemic Stroke Segmentation, Multimodal MRI, Automation Bias
320
SELF-SUPERVISED WEATHER DATA CLUSTERING FOR INSPECTING LOCAL CLIMATE CHANGE
Lívia Cereja Meinhardt, Dário Augusto Borges Oliveira
Lívia Meinhardt
As global warming worsens, we observe an increase in the frequency, duration, and intensity of weather phenomena such as heavy rainfall, heatwaves, and droughts. This project addresses the need for adaptable models by examining these impacts through local climate data, gathering evidence of shifts in climate patterns over time. To conduct the analysis, a self-supervised technique called Swapping Assignments between multiple Views (SwAV) is used alongside ERA 5 Reanalysis data, focused on an area in Brazil characterized by high population density and extensive agricultural land. The methodology has shown promising results, creating meaningful clusters based on temperature and precipitation in the selected region, which could enhance models or applications reliant on weather data.
Weather Clustering, Climate change, Self-Supervised Learning, Earth observation
321
Predictive Models for Water Quality in Laguna del Sauce (Maldonado, Uruguay)
Natalia Botto, Carolina Crisci, Rafael Terra
Natalia Botto
In this work, random forest models were developed to generate water quality predictions (i.e., chlorophyll-a) with one to five days of anticipation. Water quality, hydrological, and meteorological variables, as well as historical data in the "perfect forecasts" scenario, were used.
water quality, predictive models, weather forecasts
322
Do we need more complex representations for structure? A comparison of note duration representation for Music Transformers
Deborah Guimarães, Gabriel Souza, Flavio Figueiredo and Alexei Machado
Deborah Guimarães
In recent years, deep learning has achieved formidable results in creative computing. When it comes to music, one viable model for music generation are Transformer based models. However, while transformers models are popular for music generation, they often rely on annotated structural information. In this work, we inquire if the off-the-shelf Music Transformer models perform just as well on structural similarity metrics using only unannotated MIDI information. We show that a slight tweak to the most common representation yields small but significant improvements. We also advocate that searching for better unannotated musical representations is more cost-effective than producing large amounts of curated and annotated data.
Music Composition, Creative Computing, Deep Learning
323
Training strategies for automatic classification of Pampas wetlands
Estefanía Piegari, Rafael Grimson, Mercedes Salvia, Priscilla Minotti, Patricia Kandus
Estefanía Piegari
This study evaluates different training strategies for classifying Pampas wetlands using Landsat 5 and 8 imagery, leveraging Random Forest algorithms across six pilot sites with different ecological conditions. The first step involved creating a database of labeled points. For each site, 1,500 points were randomly selected and labeled by an expert as dry or humid (roads, buildings, and forests were excluded) for each of the 16 images consisting of one dry and one wet image per season for both sensors.Subsequently, various training strategies were assessed. A nested cross-validation schema was employed to evaluate the classification performance of the different models. Once the optimal model was identified, it was applied to the entire Landsat 5 and 8 image series (1984–2022) to generate wet frequency maps for each pilot site. Points with a wet frequency above a given threshold are then interpreted as wetlands. Finally, an evaluation was conducted for wetland maps produced under different frequency thresholds. Preliminary results suggest that the training strategy has less impact on the final product compared to the selected frequency thresholds. The ultimate model choice depends on the classification objectives, as there is a significant trade-off between precision and recall.
Wetlands, Remote sensing, Random Forest
324
Chapter 1 Integrating Secondary Structure Predictions for Enhanced Segmentation of Cryo-EM Maps
Manuel Zumbado-Corrales, Juan Esquivel-Rodríguez
Manuel Zumbado Corrales
Accurate segmentation of cryo-electron microscopy (cryo-EM) maps at intermediate resolutions remains a challenge due to noise and the complexity of macromolecular assemblies. Traditional deep learning-based methods primarily rely on voxel intensities, limiting their ability to capture underlying structural information. In this work, we propose a dual-branch 3D U-Net that integrates secondary structure probability maps from Emap2sec alongside raw cryo-EM data and user-defined extreme points to enhance segmentation.The first branch processes cryo-EM maps, incorporating interactive extreme points to refine local predictions, while the second branch leverages secondary structure priors from a pretrained model to provide complementary global context. The two branches are fused through a shared backbone with residual connections and attention mechanisms to enhance feature representations and improve segmentation accuracy.By reusing learned structural priors, our approach demonstrates the potential of leveraging prior knowledge and user interaction to enhance segmentation interpretability and assist in structural analysis. Our findings suggest that incorporating domain-specific structural information can address key limitations in segmentation tasks to enhance macromolecular segmentation workflows at intermediate resolutions.
Cryo-EM segmentation, Secondary structure integration, Deep Learning
325
Sample-Efficient Multi-Task and Multi-Objective Reinforcement Learning by Combining Multiple Behaviors
Lucas N. Alegre, Ana L. C. Bazzan, Bruno C. da Silva
Lucas Alegre
One of the main challenges in the field of artificial intelligence, and reinforcement learning (RL) in particular, is the development of generalist and flexible agents that are capable of solving multiple tasks---each requiring the agent to learn a potentially new, specialized behavior. Importantly, tackling this challenge requires agents to learn behaviors that may involve optimizing a single objective, or trading off between multiple conflicting objectives. In this work, we study the problem of how to design flexible RL agents that can, in a sample-efficient manner, adapt their behavior to solve any given tasks---each of which is defined by multiple (possibly conflicting) objectives. We introduce new multi-policy methods that empower RL agents to (i) carefully learn multiple behaviors, each specialized in a different task or in tasks in which an agent assigns different priorities (or preferences) to each of its objectives; and (ii) combine previously-learned behaviors to efficiently identify solutions to novel tasks. The methods we investigate and introduce have important theoretical guarantees regarding the optimality of the set of behaviors they identify and their capability of solving new tasks in a zero-shot manner, even in the presence of function approximation errors.
Reinforcement learning, Multi-objective RL, Multi-task RL
326
DataPruebas: A User-Friendly Platform for Data Collection
Lara Gauder, Gustavo Juantorena, Luciana Ferrer, Juan Kamienkowski
Lara Gauder
We present a user-friendly Spanish platform designed to facilitate data collection. This website taps into people's enthusiasm for participation in science. The users can register, browse, and engage in different experiments either online with instant access or asynchronously via a flexible scheduling system. For researchers, the platform simplifies the process of uploading experimental protocols and specifying participant criteria based on demographic variables such as age, place of birth, and other relevant characteristics.Our goal is to introduce this platform to the native Spanish research community and invite researchers to use it. Additionally, we aim to collaborate by sharing the site's code, enabling translation into other languages, and facilitating its adaptation for use in specific communities. This initiative seeks to expand research opportunities and enhance global cooperation in scientific studies. Because we recognize the challenges of collecting large datasets in regions with limited resources, we want to facilitate the generation of extensive datasets, which are essential for the development of new machine-learning models in a community where such advancements are currently underrepresented.
dataset collection, community research, cognitive experiments
327
Symbolic FOND Planning
Viviane Bonadia dos Santos, Leliane Nunes de Barros
Viviane Bonadia dos Santos
Automated Planning for Artificial Intelligence is the area that studies the process of choosing and organizing actions (synthesis of a plan) with the objective of reaching predetermined goals for a software or robotic agent. Fully Observable Non-Deterministic (FOND) planning is an approach that models a sequential decision-making agent with full observability and non-deterministic actions. Thus, the solution to a FOND planning problem is a set of state-action pairs that guide the agent from its initial state to a goal state. To solve this problem, several approaches have been proposed, including solutions based on heuristic search and temporal logic reasoning.In this work, we present a symbolic approach to FOND planning. Our planner is based on model checking and alpha-CTL logic. The experiments demonstrate that our planner can efficiently find solutions for complex planning goals, compared to state-of-the-art FOND planners.
Planning, Planning under uncertainty, symbolic planning
328
Adversarial Attacks on Multimodal Deep Learning Neural Networks for AD Diagnosis
Claudio Sebastian Sigvard, German Mato
Claudio Sebastian Sigvard
In recent years, neural networks have been employed to implement a wide range of use cases, from image classification and speech recognition to disease prediction and the development of advanced generative models. As adoption grows, ensuring their robustness against malicious attacks is an urgent challenge. In particular, these models are vulnerable to adversarial attacks, where subtle input perturbations, invisible to humans, manipulate system behavior to benefit the attacker. Our research focuses on analyzing these adversarial attacks in the context of multimodal deep neural networks applied to medical environments. As a case study, we chose the classification of Alzheimer's patients versus cognitively normal individuals, using magnetic resonance imaging (MRI) and clinical data from psychophysical evaluations. After training the models under different conditions, we generated and evaluated adversarial attacks using the FGSM and DeepFool methods, revealing differences in the characteristics of these attacks. Additionally, we identified statistical features in the average attacks with clinically relevant interpretations. In conclusion, we successfully analyzed the robustness of multimodal models in the medical field against various adversarial attacks. Moreover, we leveraged these attacks to examine the statistical characteristics of the populations that the neural network learns from to solve the classification problem.
Adversarial, Multimodal, Alzheimer
329
Gun detección for LATAM context
Luis Leal
Luis Leal
Crimes such as armed robbery are one of the biggest security problems in Latin America. Although gun detection models exists in industry and academia, they are not focused on the Latin American context and they lack potential scenarios present in some countries of the region such as robberies in stoplights or handmade guns, a model trained with data for this scenarios can be useful for the region
Gun detection, computer vision, Edge AI
330
Data characterization for improved training sets using iterative model training dynamics
Moacir Antonelli Ponti; Arthur Ferreira Pereira; Thais Helena Ferreira; Lucas de Angelis Oliveira; Jade Manzur; Mathias Esteban; Valentina García;Luiz Ricardo Argerich
Moacir Ponti
Real world datasets contain instances that contribute differently during the training stage of a supervised model. This motivates studies to better understanding of the role of data instances with respect to their contribution in good metrics in models. In this paper we propose a method based on metrics computed from training dynamics of Gradient Boosting Decision Trees (GBDTs) and Neural Networks (NNs) to assess the behavior of each training example. We focus on datasets containing mostly tabular or structured data, for which we use either NN epochs or estimators of GBDTs. Our results include ideas for undersampling of instances with low contribution to the learning process, as well as noisy instances removal, showing similar or improved overall metrics as well as more robust results in out-of-distribution scenarios.
data quality, label noise, uncertainty
331
Evaluating In-Context Learning Ability in Vision-Language Models
Gabriel Oliveira dos Santos, Esther Colombi, Sandra Avila
Gabriel Santos
Large Language Models (LLMs) have demonstrated remarkable capabilities in various Natural Language Processing (NLP) tasks, with in-context learning emerging as a key ability that enables models to generalize from a few examples without parameter updates. However, the extension of this ability to Vision-Language Models (VLMs) remains underexplored, particularly in the context of image captioning. In this paper, we systematically analyze in-context learning in VLMs, evaluating six models from four architectures across three image captioning and four Visual Question Answering (VQA) benchmarks. We investigate the impact of instruction-tuning, prompt construction, and demonstration selection on in-context learning performance. Our findings reveal that VLMs exhibit weak in-context learning abilities, often struggling to leverage contextual information effectively. Increasing the number of demonstrations does not necessarily improve performance, and instruction-tuning appears to hinder in-context learning. Additionally, models trained on interleaved image-text datasets show slight advantages, while prompt design plays a crucial role—structured prompts significantly enhance model performance compared to simple concatenation.
vision-language models, multimodality, in-context learning,
332
FG-VLM: A Fact-Guided Vision-Language Model for Visual Grounding and Binary Factual Question Answering in Chest X-ray Analysis
Pablo Messina, René Vidal, Denis Parra, Álvaro Soto, Vladimir Araujo
Pablo Messina
Factual correctness is crucial in medical scenarios, whether for image classification, visual anomaly detection, or report generation. Despite AI advancements in this area, challenges remain due to limited expert-labeled data, particularly for rare diseases with different annotation protocols across datasets. To address this, we introduce FG-VLM, a multimodal vision-language model that enhances factual accuracy and interpretability by integrating text and image representations in a multitask optimization setting. Given an input chest X-ray and a textual fact, we jointly learn to answer binary factual questions and to identify image regions associated with the fact. We evaluate our approach on VinDr-CXR, a dataset of 18K chest X-rays annotated with 28 abnormalities. We demonstrate that visual grounding significantly improves binary fact classification, outperforming competitive baselines. Moreover, we integrate facts from another large-scale dataset named MIMIC-CXR and revise the VinDr-CXR labels with radiologists to promote a more consistent representation of lung opacity annotations. These measures boost lung opacity classification from 17.9% to 90.6% AUPRC without affecting or even improving the performance over other abnormalities, such as cardiomegaly and pleural effusion.
Vision-Language Models, Chest X-ray Analysis, Visual Grounding
333
DUDF: Differentiable Unsigned Distance Fields with hyperbolic scaling
Miguel Fainstein, Viviana Siless, Emmanuel Iarussi
Emmanuel Iarussi
In recent years, there has been a growing interest in training Neural Networks to approximate Unsigned Distance Fields (UDFs) for representing open surfaces in the context of 3D reconstruction. However, UDFs are nondifferentiable at the zero level set which leads to significant errors in distances and gradients, generally resulting in fragmented and discontinuous surfaces. In this paper, we propose to learn a hyperbolic scaling of the unsigned distance field, which defines a new Eikonal problem with distinct boundary conditions. This allows our formulation to integrate seamlessly with state-of-the-art continuously differentiable implicit neural representation networks, largely applied in the literature to represent signed distance fields. Our approach not only addresses the challenge of open surface representation but also demonstrates significant improvement in reconstruction quality and training performance. Moreover, the unlocked field’s differentiability allows the accurate computation of essential topological properties such as normal directions and curvatures, pervasive in downstream tasks such as rendering. Through extensive experiments, we validate our approach across various data sets and against competitive baselines. The results demonstrate enhanced accuracy and up to an order of magnitude increase in speed compared to previous methods.
Differentiable Neural Networks, Implicit Surface Representation, Unsigned Distance Functions
334
From Dense to Symbolic: Learning Abstractions via Sequential Discrete Representations (LASR)
Victor Sebastian Martinez Pozos, Ivan Vladimir Meza Ruiz
Victor Sebastian Martinez Pozos
This work explore how complex visual information can be abstracted into discrete symbolic sequences using self-supervised learning. Inspired by how language structures information for reasoning and generalization, we extend the DINO framework to generate symbolic representations from images. Our approach uses a transformer decoder with cross-attention, making the representations more interpretable by linking symbols to image regions. Initial results show promising levels of abstraction, laying the groundwork for more transparent and structured visual understanding.
Symbolic Representations, Learning Representations, Self Supervised Learning
335
Optimización Evolutiva de modelos para la Detección de Trastornos del Lenguaje
I. Kemmerer , M. F. Gerard , L. D. Vignolo
iara kemmerer
Los trastornos específicos del lenguaje (SLI) afectan las habilidades comunicativas de los niños, por lo que su detección temprana es clave para una intervención adecuada. Investigaciones previas hemos demostrado el potencial de las redes neuronales convolucionales (CNN) y modelos híbridos que combinan CNN con redes recurrentes para esta tarea.Con el objetivo de mejorar la detección de SLI, proponemos el uso de algoritmos evolutivos para la optimización de hiperparámetros. Inspirados en principios de selección natural, estos algoritmos permiten explorar de manera eficiente el espacio de configuraciones sin necesidad de realizar una búsqueda exhaustiva.Nuestro enfoque se centra en el diseño de un algoritmo evolutivo para ajustar hiperparámetros clave, como la tasa de aprendizaje. Además, analizamos el esquema de particionado de datos para lograr particiones más estables y minimizar la variabilidad observada.Los resultados muestran que la optimización mediante algoritmos evolutivos contribuye a mejorar el rendimiento de los clasificadores, aumentando la precisión en la detección de SLI.
SLI, Algoritmo Evolutivo, Redes Neuronales
336
Physics-guided deep learning for digital holographic microscopy
Juan Llaguno, Julia Alonso, Federico Lecumberry
Juan Llaguno
Holography was invented by Gabor in 1948 and involves recording the interference pattern, called a hologram, generated by light coming from an object and a reference beam. When the hologram is recorded by a camera sensor, the technique is referred to as digital holography (DH). If the specimen to be imaged is microscopic and an optical setup consisting of a microscope objective, lenses, mirrors, and beam splitters is used, the technique is called digital holographic microscopy.The reconstruction of a digitally captured hologram is performed computationally using wave optics and signal processing. However, these calculations can be time-consuming, as many of them are iterative or require manual inputs that cannot be automated consistently. In this regard, Deep Learning (DL) has demonstrated impressive results in the fields of image processing, microscopy, and beyond. DL has been applied to DH in various ways, including depth estimation, phase unwrapping, and direct hologram reconstruction using both supervised and unsupervised learning.Physics-guided DL involves incorporating physical constraints into the loss function of a DL model to ensure that the results adhere to the underlying physical laws. This approach enhances the interpretability of the acquired results, making it a valuable tool for DH reconstruction.
Digital Holography, Image Processing, Physics-guided deep learning
337
Comparing Knowledge Injection Methods for LLMs in a Low-Resource Regime
Hugo Abonizio, Thales Almeida, Roberto Lotufo, Rodrigo Nogueira
Hugo Abonizio
Updating large language models (LLMs) with small amounts of text remains challenging due to issues like catastrophic forgetting. This study examines how to inject limited, unstructured knowledge into LLMs and evaluates learning outcomes using a dataset of recent news. By probing models with question-answer pairs, researchers assess knowledge acquisition while ensuring no overlap with pre-training data.Baseline experiments show that simple continued pre-training on limited data leads to modest gains. However, using synthetic data generation techniques—especially those that introduce greater textual diversity—enhances knowledge retention. Diverse prompting methods significantly improve the model’s ability to learn new facts while mitigating forgetting.The study also highlights the limitations of retrieval-augmented generation (RAG) for knowledge injection. RAG-based approaches often degrade performance on control datasets more than parametric updates, suggesting higher sensitivity to injected content.Additionally, the findings suggest that models can generate effective synthetic training data, potentially enabling self-improving updates. This research underscores the importance of balancing new knowledge integration with preserving existing capabilities, offering insights into efficient and reliable small-scale model adaptation.
Large language models, Knowledge injection, Synthetic data
338
A Large-Scale High-Resolution Satellite Dataset with Shadow Masks
Elías Masquil, Roger Marí, Thibaud Ehret, Gabriele Facciolo, Pablo Musé
Elías Masquil
We introduce the first large-scale, high-resolution satellite dataset featuring shadow masks. Built from publicly available imagery, the dataset is carefully processed through tiling, bundle adjustment, and precise alignment with ground truth DSMs. Shadow masks are generated by an algorithm that cast rays over the DSM knowing the sun position, providing a valuable resource for various remote sensing and computer vision applications. We train a shadow detection model that refines noisy labels. This dataset opens new opportunities for improving Earth observation, 3D scene understanding, and satellite-based image analysis.
satellite imagery, shadow detection, remote sensing
339
When AI Met Education: Can They Ever Just Be Friends?
Germán Capdehourat, Isabel Amigo, Ana Clara Nóbile, Brian Lorenzo, Joaquín Trigo, Federica Bascans, María Eugenia Curi, Víctor Koleszar, Pablo Pages, Lucías Pimás, Sofía García, et al.
Germán Capdehourat
In recent years, artificial intelligence has become an integral part of educational innovation. As Uruguay’s national agency for technology-based innovation in education, Ceibal has been pioneering AI-based initiatives to enhance learning experiences. This poster presents two key aspects of Ceibal’s efforts: R&D projects and technological solutions powered by AI, as well as initiatives to bring AI literacy to the educational system. On the technological front, AI-driven applications support teachers and students in various ways, including examples such as LLMs-assisted feedback on text and image-based assignments, or automated assessment of spoken English by means of speech audio analysis. Beyond technology, Ceibal is committed to fostering AI understanding in education through courses and workshops for teachers and students, as well as publications that introduce fundamental AI concepts. These resources explore topics like supervised learning, algorithmic bias, and the ethical implications of AI usage. Taking inspiration from the movie When Harry Met Sally, we pose the question: Can AI and education ever just be friends? This poster explores how AI and education are building a collaborative relationship, shaping the future of learning.
education, AI Literacy, computational thinking
340
Variational Autoencoders for Alzheimer's Disease Classification
Santiago Valentino Blas Laguzza, Martin Alberto Belzunce, Diego Mateos
santiago valentino blas laguzza
In this study, we explore the use of Variational Autoencoders (VAEs) to extract latent features from functional connectivity matrices derived from fMRI data of subjects with Alzheimer's Disease (AD) and cognitively normal (CN) individuals. We utilize these latent representations to classify subjects into AD and CN groups using various machine learning classifiers. The results demonstrate that the latent features learned by the VAE can effectively distinguish between AD and CN subjects, highlighting the potential of deep generative models in neuroimaging analysis and early detection of Alzheimer's Disease.
Variational autoencoders - alzheimer - diagnosis
341
Responsible Application of Artificial Intelligence in the Bolivian Context
Lara Ramos Nayara Carminia , Silva Plata Miguel Ángel , Salazar Edgar
Nayara Lara Ramos
This project proposes guidelines to strengthen knowledge and technological development in the field of Artificial Intelligence in Bolivia. Globally, AI has transformed multiple sectors, such as education, health, industry and security. However, in Bolivia there are not enough tools to guide the population about its use, regulation and possible implications.This proposal seeks to generate a document that establishes clear guidelines on the rights, responsibilities and considerations in the development and application of AI. Through research, it seeks to facilitate access to relevant information that allows students, professionals and institutions to understand the scope and limitations of these technologies. It also encourages the integration of AI in the academic and industrial environment in an ethical and safe manner, promoting its responsible adoption and promoting its positive impact on the country's development.
Artificial Intelligence, Regulation, Bolivia
342
Adversarial Attacks and LLM Safety
Matías Grinberg, Carlos Giudice, Pablo Lorenzatto
Matías Grinberg
This poster reviews security challenges in Large Language Models (LLMs), focusing on external risks from third parties and internal risks related to AI safety stemming from the model's inherent behavior.The discussion on adversarial attacks (external risks) covers prompt injections, data poisoning, and software vulnerability exploitation, among other techniques. We highlight the role of MLSecOps and proactive defense strategies in mitigating these threats, emphasizing the importance of robust security measures in LLM deployment.For AI safety (internal risks), we explore mechanistic interpretability and knowledge editing as tools for understanding and addressing these risks. We demonstrate interventions that adjust model behavior while preserving performance, using practical examples to show how targeted modifications can prevent the model from exhibiting unintended or harmful behavior.
adversarial attacks, LLM safety, AI security
343
Generalized Graph Variational Auto-Encoders
Kleyton da Costa (DI/PUC-Rio), Bernardo Modenesi (University of Utah), Ivan Menezes (DEM/PUC-Rio), Hélio Lopes (DI/PUC-Rio)
Kleyton da Costa
In this paper, we introduce the Generalized Graph Variational Auto-Encoder (GGVA), a novel framework that extends traditional Variational Graph Autoencoders by incorporating generalized divergence measures for distribution regularization in the latent space. Our main contributions are twofold: (1) a flexible variational inference framework for graph-structured data using generalized divergence measures, and (2) the empirical demonstration that these measures can improve accuracy in handling complex network topologies for link prediction tasks.
Learning on Graphs, Generalized Variational Inference, Generalized Divergence Measures, Link Prediction
344
Voices of Latin America: A low-resource TTS system for multiple accents
Jefferson Quispe Pinares
Jefferson Quispe Pinares
This research presents the implementation of a low-resource Text-to-Speech (TTS) system with accents from various regions in Latin America. The evaluation includes different sources of databases such as freely accessible corpora, synthetic data, crowdsourcing, and audio recordings made in a professional studio. The TTS performance is evaluated using metrics such as Word Error Rate (WER) and Comparative Mean Opinion Score (CMOS).
TTS, accent, synthetic data
345
Decoding Semantic Ambiguity in Large Language Models: Aligning Human Behavioral Responses with GPT-2's Internal Representations
Agustín Gianolini, Belén Paez, Facundo Totaro, Julieta Laurino, Fermín Travi, Diego Fernández Slezak, Laura Kaczer, Juan Kamienkowski, Bruno Bianchi
Bruno Bianchi
Large Language Models (LLMs) exhibit human-like text processing, yet their internal mechanisms for resolving semantic ambiguity remain opaque, similar to the “black box” of human cognition. This study investigates how LLMs disambiguate concrete nouns by comparing their semantic biases to human behavioral responses. A corpus of sentences containing ambiguous words (e.g., “arco”) paired with biasing contexts (e.g., short paragraphs related to “football” and “architecture”) was created. Human participants identified their perceived meanings of ambiguous words in these contexts, establishing a behavioral ground truth. To analyze GPT2’s disambiguation processes, two technical steps were implemented: (1) the model was fine-tuned to obtain a word-based tokenization, and (2) each ambiguous word’s meaning was defined using curated word lists. The model’s semantic bias was measured via cosine distances between contextualized embeddings of ambiguous words. Results revealed that GPT2’s middle layers correlated with human disambiguation patterns, particularly when using word-based tokenization, mirroring findings in human-model alignment research. This suggests shared computational principles between human cognition and LLM processing for resolving ambiguity. The study advances interpretability research by linking model-internal representations to human behavioral benchmarks, offering insights into both artificial and biological language systems.
LLMs, Human, Disambiguation