Christos Theodoropoulos
AI Solutions Architect @ Qity
Hello, world!
Hi, I'm Christos Theodoropoulos — currently employed as AI Solutions Architect at Qity, working alongside the developers and system architects to lay the foundations for AI-driven solutions, helping to strengthen and extend the capabilities of Qity platforms on the intersection of Engineering, Regulatory, Quality, and AI. Previously, I worked as Senior Data Scientist at EarlyTracks, where I used artificial intelligence and natural language processing to turn electronic health records into meaningful formal insights. I'm passionate about applying machine learning and artificial intelligence tools to real-world problems, especially in life sciences and human-centered technologies.
I studied Electrical and Computer Engineering at the National Technical University of Athens (NTUA), where I focused on computer science and graduated with great distinction. My thesis explored how deep learning can be used for human emotion recognition from facial expressions in real-time video conversations, uncovering the nuanced interplay of emotions in dynamic interactions — think of it as teaching machines to read the room. After that, I worked on eye-tracking and gaze localization in driving scenarios at the I-SENSE Group, before moving to Belgium to pursue an advanced Master's in Artificial Intelligence at KU Leuven. There, I dug into fMRI data and used deep neural networks to clean up brain scans — work that was later published in a signal processing conference (EUSIPCO).
In my last academic journey, starting at 2020, I pursued my PhD in Computer Science at KU Leuven, focusing on natural language processing and knowledge extraction. I spearheaded the creation of an end-to-end open-source knowledge extraction system from the ground up. This endeavor, potentially incorporated the expert-in-the-loop paradigm, seamlessly aligns with the tenets of lifelong learning. Recognizing the challenge of navigating vast volumes of research text daily, my unwavering focus has centered on the realm of biomedical text. Within this domain, I've embarked on a mission with far-reaching implications by tackling the intricate complexities of two formidable yet unresolved diseases: Alzheimer's disease and Rett syndrome.
However, my aspirations don't stop at disease comprehension through seamless knowledge extraction. During my PhD, my research extended to the frontier of personalized medicine, where I harnessed the potential of person-centric knowledge graphs to create a holistic view of patients. A notable accomplishment that adorns my research journey is the creation of a contrastive learning framework, ingeniously integrating both graph and text modalities to instill relation-oriented structure into Language Models like BERT and RoBERTa. This novel approach has empowered me to transcend the constraints of traditional text encoders, ushering in a new era of possibilities. By translating the acquired embedding spaces into tangible solutions, I've ventured into the realms of relation extraction and named entity recognition, solving these intricate tasks using deceptively simple yet effective classifiers like KNN. At the later stage of my PhD, I've had the chance to conduct a short research visit in the Idiap Research Institute in Switzerland. I've also attended two OxML summer schools organized by AI for Global Goals in collaboration with CIFAR and the University of Oxford diving deeper into health AI, representation learning, and generative models. Along the way, I've served as a reviewer for top journals and conferences like ACL Rolling Review and IEEE TPAMI.
Beyond academia, my expedition led me to the vanguard of innovation as a research scientist intern at IBM Research. Here, I had the privilege of immersing myself in projects that not only stoked the flames of my curiosity but also enriched my repertoire of skills. A significant chapter in this journey involved insights from Electronic Health Records (EHR) to construct person-centric knowledge graphs. This endeavor saw me wield the power of the HSPO ontology and harness the prowess of Graph Neural Networks (GNNs) to tackle the formidable task of predicting intensive care unit readmissions. Embracing the spirit of versatility, my explorations expanded to encompass the fascinating domain of embedding learning for heterogeneous graphs. These explorations are on the brink of yielding results in the shape of upcoming research publications. The team's influence also extends into the realm of open-source collaboration. I've been instrumental in fortifying IBM's commitment to knowledge dissemination, playing a pivotal role in bolstering their open-source initiative, exemplified by the repository. In a testament to my innovation, and inventiveness, I proudly stand as the primary inventor in a patent filing.
As for my roots, I hail from Tripolis, the capital of Arcadia, steeped in history and surrounded by beautiful nature. My formative years were then shaped in Athens, where seven years of studying, working, and immersing myself in the city's energy left an indelible mark. Today, I'm nestled in Brussels, a cosmopolitan hub pulsating at the heart of Europe, characterized by its multicultural essence and lively spirit.
For deeper insights into my journey and potential collaborations, I invite you to explore my CV or reach out to me directly. And if the allure of Greece beckons, I stand ready to offer recommendations. Here's to embracing the journey of knowledge, discovery, and shared experiences!
Experience
Education
Professional Experience
News
- 2025
- 10/2025 Appointed by the Research Executive Agency, under the authority of the European Commission, to serve as Scientific Expert.
- 09/2025 Our paper "Reduction of Supervision for Biomedical Knowledge Discovery" with Andrei Catalin Coman, dr. James Henderson, and prof. Marie-Francine Moens got accepted into the BMC Bioinformatics journal.
- 07/2025 Accepted an offer to join Qity as AI Solutions Architect.
- 06/2025 Our paper "Fast-and-Frugal Text-Graph Transformers are Effective Link Predictors" with Andrei Catalin Coman, prof. Marie-Francine Moens and dr. James Henderson got accepted into ACL '25 (findings).
- 04/2025 Released the pre-print of our publication "Reduction of Supervision for Biomedical Knowledge Discovery" with Andrei Catalin Coman, dr. James Henderson, and prof. Marie-Francine Moens.
- 03/2025 Officially defended my PhD publicly.
- 01/2025 Successfully defended my PhD privately.
- 01/2025 Accepted an offer to join EarlyTracks as Senior Data Scientist, aiming to improve the quality of Electronic Health Records.
- 2024
- 11/2024 Our paper "Enhancing Biomedical Knowledge Discovery for Diseases: An End-To-End Open-Source Framework" with Andrei Catalin Coman, dr. James Henderson, and prof. Marie-Francine Moens got accepted into the IEEE Access journal.
- 07/2024 Participated in OxML summer schools on health and bio AI and representation learning and generative AI, organized by AI for Global Goals in collaboration with CIFAR and the University of Oxford.
- 06/2024 Our follow-up paper "Evaluating the Predictive Features of Person-Centric Knowledge Graph Embeddings: Unfolding Ablation Studies" with Natasha Mulligan and dr. Joao Bettencourt-Silva got accepted into MIE '24.
- 06/2024 Our paper "GADePo: Graph-Assisted Declarative Pooling Transformers for Document-Level Relation Extraction" with Andrei Catalin Coman, prof. Marie-Francine Moens and dr. James Henderson got accepted into KnowledgeNLP-ACL '24.
- 04/2024 Conducted a short research visit at Idiap Research Institute and gave a talk on knowledge discovery.
- 2023
- 10/2023 Our paper "Representation Learning for Person or Entity-Centric Knowledge Graphs: An Application in Healthcare" with Natasha Mulligan, prof. Thaddeus Stappenbeck, dr. Joao Bettencourt-Silva got accepted into K-CAP '23.
- 09/2023 Presented our paper "An Information Extraction Study: Take In Mind the Tokenization!" (oral talk) at EUSFLAT '23.
- 03/2023 Our paper "An Information Extraction Study: Take In Mind the Tokenization!" with prof. Marie-Francine Moens got accepted into EUSFLAT '23.
- 2022
- 11/2022 Gave a talk on Person-Centric Knowledge Graph Extraction from Electronic Health Records to solve downstream tasks in "Show & Tell" session of IBM Research.
- 10/2022 Submitted my first patent as the primary inventor, working in IBM Research.
- 10/2022 Heavily contributed to IBM's open-source project (HSPO ontology).
- 01/2022 Accepted an offer to join IBM Research (Human-centric AI team) for a research scientist internship.
- 2021
- 11/2021 Presented our paper (lecture talk) about imposing relation structure in language-model embeddings using contrastive learning at CoNLL '21.
- 10/2021 The official code of our paper "Imposing Relation Structure in Language-Model Embeddings Using Contrastive Learning" has been released.
- 09/2021 Our paper "Imposing Relation Structure in Language-Model Embeddings Using Contrastive Learning" with dr. James Henderson, Andrei Catalin Coman and prof. Marie-Francine Moens got accepted into CoNLL '21.
- 08/2021 Presented our paper about automatic denoising of resting-state fMRI using deep learning at EUSIPCO '21.
- 07/2021 Became member of ContinualAI organization.
- 04/2021 Our work with dr. Christos Chatzichristos and prof. Sabine Van Huffel on automatic denoising of resting-state fMRI using deep learning got accepted into EUSIPCO '21.
- 2020 & Earlier
- 09/2020 Received FWO Ph.D. fellowship.
- 08/2020 Graduated from KU Leuven, M.Sc. in Artificial Intelligence, with Magna Cum Laude.
- 07/2019 Received scholarship for postgraduate studies by Eugenides Foundation for the academic year of 2019-2020.
- 06/2019 Received scholarship for postgraduate studies by Bodossaki Foundation for the academic year of 2019-2020.
- 10/2018 Graduated from National and Technical University of Athens, M.Eng. in Electrical and Computer Engineering, with great distinction.
Publications
2025
2024
2023
2021
Contact
My first name (Christos) is pronounced as: