Additionally, we conduct ablation studies to explore the robustness of our method concerning various hyperparameters.

Then,wecalculatethe mean stiffness of the value network across all state pairs and report its average computed over all trainingepochs. Eachagentis trained on 200 training levels for 25M environment steps. The mean and standard deviation are computedover10differentruns. Morespecifically,wecollect100 training episodes throughout the training and evaluate the value network prediction for the initial stateofeachtrajectory. Each agent is trained on 200 training levels for 25M environment steps.

We appreciate the reviewers' thoughtful comments. We will do our best to address the reviewers' other points in the paper's next version. Incorrect link to code and reproducibility (R1, R3): We most sincerely apologize for the error! We have verified that the code is now available at the included link. R3 on assumption for Theorem 4.2: This simplifying assumption is contained to Section 4.2 of the paper, for the purpose Our analysis and experiments do not require this assumption in general.

The 12-lead electrocardiogram (ECG) is the gold standard for cardiovascular monitoring, offering superior diagnostic granularity and specificity compared to photoplethysmography (PPG). However, existing 12-lead ECG systems rely on cumbersome multi-electrode setups, limiting sustained monitoring in ambulatory settings, while current PPG-based methods fail to reconstruct multi-lead ECG due to the absence of inter-lead constraints and insufficient modeling of spatial-temporal dependencies across leads. To bridge this gap, we introduce P2Es, an innovative demographic-aware diffusion framework designed to generate clinically valid 12-lead ECG from PPG signals via three key innovations. Specifically, in the forward process, we introduce frequency-domain blurring followed by temporal noise interference to simulate real-world signal distortions. In the reverse process, we design a temporal multi-scale generation module followed by frequency deblurring. In particular, we leverage KNN-based clustering combined with contrastive learning to assign affinity matrices for the reverse process, enabling demographic-specific ECG translation. Extensive experimental results show that P2Es outperforms baseline models in 12-lead ECG reconstruction.

This study introduces a novel method that transforms multimodal physiological signals -- photoplethysmography (PPG), galvanic skin response (GSR), and acceleration (ACC) -- into 2D image matrices to enhance stress detection using convolutional neural networks (CNNs). Unlike traditional approaches that process these signals separately or rely on fixed encodings, our technique fuses them into structured image representations that enable CNNs to capture temporal and cross - signal dependencies more effectively. This image - based transformation not only improves interpretability but also serves as a rob ust form of data augmentation. To further enhance generalization and model robustness, we systematically reorganize the fused signals into multiple formats, combining them in a multi - stage training pipeline. This approach significantly boost s classification performance, with test accuracy improving from 92.57% (using individual signal orderings) to 95.86% when using the combined strategy. While demonstrated here in the context of stress detection, the proposed method is broadly applicable to any domain invo lving multimodal physiological signals, paving the way for more accurate, personalized, and real time health monitoring through wearable technologies.