Western Norway
Foundation Models -- A Panacea for Artificial Intelligence in Pathology?
Mulliqi, Nita, Blilie, Anders, Ji, Xiaoyi, Szolnoky, Kelvin, Olsson, Henrik, Boman, Sol Erika, Titus, Matteo, Gonzalez, Geraldine Martinez, Mielcarz, Julia Anna, Valkonen, Masi, Gudlaugsson, Einar, Kjosavik, Svein R., Asenjo, José, Gambacorta, Marcello, Libretti, Paolo, Braun, Marcin, Kordek, Radzislaw, Łowicki, Roman, Hotakainen, Kristina, Väre, Päivi, Pedersen, Bodil Ginnerup, Sørensen, Karina Dalsgaard, Ulhøi, Benedicte Parm, Ruusuvuori, Pekka, Delahunt, Brett, Samaratunga, Hemamali, Tsuzuki, Toyonori, Janssen, Emilius A. M., Egevad, Lars, Eklund, Martin, Kartasalo, Kimmo
The role of artificial intelligence (AI) in pathology has evolved from aiding diagnostics to uncovering predictive morphological patterns in whole slide images (WSIs). Recently, foundation models (FMs) leveraging self-supervised pre-training have been widely advocated as a universal solution for diverse downstream tasks. However, open questions remain about their clinical applicability and generalization advantages over end-to-end learning using task-specific (TS) models. Here, we focused on AI with clinical-grade performance for prostate cancer diagnosis and Gleason grading. We present the largest validation of AI for this task, using over 100,000 core needle biopsies from 7,342 patients across 15 sites in 11 countries. We compared two FMs with a fully end-to-end TS model in a multiple instance learning framework. Our findings challenge assumptions that FMs universally outperform TS models. While FMs demonstrated utility in data-scarce scenarios, their performance converged with - and was in some cases surpassed by - TS models when sufficient labeled training data were available. Notably, extensive task-specific training markedly reduced clinically significant misgrading, misdiagnosis of challenging morphologies, and variability across different WSI scanners. Additionally, FMs used up to 35 times more energy than the TS model, raising concerns about their sustainability. Our results underscore that while FMs offer clear advantages for rapid prototyping and research, their role as a universal solution for clinically applicable medical AI remains uncertain. For high-stakes clinical applications, rigorous validation and consideration of task-specific training remain critically important. We advocate for integrating the strengths of FMs and end-to-end learning to achieve robust and resource-efficient AI pathology solutions fit for clinical use.
Understanding Federated Learning from IID to Non-IID dataset: An Experimental Study
Seo, Jungwon, Catak, Ferhat Ozgur, Rong, Chunming
As privacy concerns and data regulations grow, federated learning (FL) has emerged as a promising approach for training machine learning models across decentralized data sources without sharing raw data. However, a significant challenge in FL is that client data are often non-IID (non-independent and identically distributed), leading to reduced performance compared to centralized learning. While many methods have been proposed to address this issue, their underlying mechanisms are often viewed from different perspectives. Through a comprehensive investigation from gradient descent to FL, and from IID to non-IID data settings, we find that inconsistencies in client loss landscapes primarily cause performance degradation in non-IID scenarios. From this understanding, we observe that existing methods can be grouped into two main strategies: (i) adjusting parameter update paths and (ii) modifying client loss landscapes. These findings offer a clear perspective on addressing non-IID challenges in FL and help guide future research in the field.
Segmentation of Non-Small Cell Lung Carcinomas: Introducing DRU-Net and Multi-Lens Distortion
Oskouei, Soroush, Valla, Marit, Pedersen, André, Smistad, Erik, Dale, Vibeke Grotnes, Høibø, Maren, Wahl, Sissel Gyrid Freim, Haugum, Mats Dehli, Langø, Thomas, Ramnefjell, Maria Paula, Akslen, Lars Andreas, Kiss, Gabriel, Sorger, Hanne
Considering the increased workload in pathology laboratories today, automated tools such as artificial intelligence models can help pathologists with their tasks and ease the workload. In this paper, we are proposing a segmentation model (DRU-Net) that can provide a delineation of human non-small cell lung carcinomas and an augmentation method that can improve classification results. The proposed model is a fused combination of truncated pre-trained DenseNet201 and ResNet101V2 as a patch-wise classifier followed by a lightweight U-Net as a refinement model. We have used two datasets (Norwegian Lung Cancer Biobank and Haukeland University Hospital lung cancer cohort) to create our proposed model. The DRU-Net model achieves an average of 0.91 Dice similarity coefficient. The proposed spatial augmentation method (multi-lens distortion) improved the network performance by 3%. Our findings show that choosing image patches that specifically include regions of interest leads to better results for the patch-wise classifier compared to other sampling methods. The qualitative analysis showed that the DRU-Net model is generally successful in detecting the tumor. On the test set, some of the cases showed areas of false positive and false negative segmentation in the periphery, particularly in tumors with inflammatory and reactive changes.
Physics-based deep learning reveals rising heating demand heightens air pollution in Norwegian cities
Cao, Cong, Debnath, Ramit, Alvarez, R. Michael
Policymakers frequently analyze air quality and climate change in isolation, disregarding their interactions. This study explores the influence of specific climate factors on air quality by contrasting a regression model with K-Means Clustering, Hierarchical Clustering, and Random Forest techniques. We employ Physics-based Deep Learning (PBDL) and Long Short-Term Memory (LSTM) to examine the air pollution predictions. Our analysis utilizes ten years (2009-2018) of daily traffic, weather, and air pollution data from three major cities in Norway. Findings from feature selection reveal a correlation between rising heating degree days and heightened air pollution levels, suggesting increased heating activities in Norway are a contributing factor to worsening air quality. PBDL demonstrates superior accuracy in air pollution predictions compared to LSTM. This paper contributes to the growing literature on PBDL methods for more accurate air pollution predictions using environmental variables, aiding policymakers in formulating effective data-driven climate policies.
AI is already more creative than YOU: ChatGPT outperformed humans in creative thinking experiment
Artificial intelligence outperforms humans in strategy games, website design and data processing, but now the tech can add creative thinking to the list. AI chatbots surpassed humans when asked to devise alternative uses for everyday objects. Researchers said the AI used a skill known as divergent thinking, a thought process or method used to generate creative ideas by exploring many possible solutions. The study by the University of Stavanger in Norway involved 256 human volunteers and three AI chatbots – ChatGPT3, ChatGPT4, and Copy.Ai - that were asked to provide multiple uses for a rope, box, pencil and candle. When assessed with a type of divergent thinking exercise known as alternate uses tasks, which asks a person to think of as many uses as possible for a simple object, chatbots, on average, performed better than humans.
AI just beat a human test for creativity. What does that even mean?
While the purpose of the study was not to prove that AI systems are capable of replacing humans in creative roles, it raises philosophical questions about the characteristics that are unique to humans, says Simone Grassini, an associate professor of psychology at the University of Bergen, Norway, who co-led the research. "We've shown that in the past few years, technology has taken a very big leap forward when we talk about imitating human behavior," he says. "These models are continuously evolving." Proving that machines can perform well in tasks designed for measuring creativity in humans doesn't demonstrate that they're capable of anything approaching original thought, says Ryan Burnell, a senior research associate at the Alan Turing Institute, who was not involved with the research. The chatbots that were tested are "black boxes," meaning that we don't know exactly what data they were trained on, or how they generate their responses, he says.
CT Perfusion is All We Need: 4D CNN Segmentation of Penumbra and Core in Patients With Suspected Ischemic Stroke
Tomasetti, Luca, Engan, Kjersti, Høllesli, Liv Jorunn, Kurz, Kathinka Dæhli, Khanmohammadi, Mahdieh
Precise and fast prediction methods for ischemic areas comprised of dead tissue, core, and salvageable tissue, penumbra, in acute ischemic stroke (AIS) patients are of significant clinical interest. They play an essential role in improving diagnosis and treatment planning. Computed Tomography (CT) scan is one of the primary modalities for early assessment in patients with suspected AIS. CT Perfusion (CTP) is often used as a primary assessment to determine stroke location, severity, and volume of ischemic lesions. Current automatic segmentation methods for CTP mostly use already processed 3D parametric maps conventionally used for clinical interpretation by radiologists as input. Alternatively, the raw CTP data is used on a slice-by-slice basis as 2D+time input, where the spatial information over the volume is ignored. In addition, these methods are only interested in segmenting core regions, while predicting penumbra can be essential for treatment planning. This paper investigates different methods to utilize the entire 4D CTP as input to fully exploit the spatio-temporal information, leading us to propose a novel 4D convolution layer. Our comprehensive experiments on a local dataset of 152 patients divided into three groups show that our proposed models generate more precise results than other methods explored. Adopting the proposed 4D mJ-Net, a Dice Coefficient of 0.53 and 0.23 is achieved for segmenting penumbra and core areas, respectively. The code is available on https://github.com/Biomedical-Data-Analysis-Laboratory/4D-mJ-Net.git.
Inductive Bias for Emergent Communication in a Continuous Setting
Villanger, John Isak Fjellvang, Bojesen, Troels Arnfred
We study emergent communication in a multi-agent reinforcement learning setting, where the agents solve cooperative tasks and have access to a communication channel. The communication channel may consist of either discrete symbols or continuous variables. We introduce an inductive bias to aid with the emergence of good communication protocols for continuous messages, and we look at the effect this type of inductive bias has for continuous and discrete messages in itself or when used in combination with reinforcement learning. We demonstrate that this type of inductive bias has a beneficial effect on the communication protocols learnt in two toy environments, Negotiation and Sequence Guess.
Underwater autonomous mapping and characterization of marine debris in urban water bodies
Fossum, Trygve Olav, Sture, Øystein, Norgren-Aamot, Petter, Hansen, Ingrid Myrnes, Kvisvik, Bjørn Christian, Knag, Anne Christine
Marine debris originating from human activity has been accumulating in underwater environments such as oceans, lakes, and rivers for decades. The extent, type, and amount of waste is hard to assess as the exact mechanisms for spread are not understood, yielding unknown consequences for the marine environment and human health. Methods for detecting and mapping marine debris is therefore vital in order to gain insight into pollution dynamics, which in turn can be used to effectively plan and execute physical removal. Using an autonomous underwater vehicle (AUV), equipped with an underwater hyperspectral imager (UHI) and stereo-camera, marine debris was autonomously detected, mapped and quantified in the sheltered bay Store Lungegaardsvann in Bergen, Norway.
Beyond Cuts in Small Signal Scenarios - Enhanced Sneutrino Detectability Using Machine Learning
Alvestad, Daniel, Fomin, Nikolai, Kersten, Jörn, Maeland, Steffen, Strümke, Inga
We investigate enhancing the sensitivity of new physics searches at the LHC by machine learning in the case of background dominance and a high degree of overlap between the observables for signal and background. We use two different models, XGBoost and a deep neural network, to exploit correlations between observables and compare this approach to the traditional cut-and-count method. We consider different methods to analyze the models' output, finding that a template fit generally performs better than a simple cut. By means of a Shapley decomposition, we gain additional insight into the relationship between event kinematics and the machine learning model output. We consider a supersymmetric scenario with a metastable sneutrino as a concrete example, but the methodology can be applied to a much wider class of supersymmetric models.