Despite the fact that biometric systems won many desirable advantages such as high security and convenience, biometric data are vulnerable to various attacks. Once the biometric data are compromised during any point of the authentication process, they are lost forever. In this paper, we propose a security information management approach to address privacy concerns emerging from the management of biometric data in remote Photoplethysmogram (rPPG) biometric authentication systems. In our design, Fully Homomorphic Encryption (FHE) is introduced to protect PPG signals in the transmission and storage phases. We further design an efficient FHE-based Convolutional Neural Network (CNN) model and encrypt the key model parameters of the CNN to realize secure inference. In addition, Principal Component Analysis, Max-Relevance and Min-Redundancy, and Relative Mutual Information methods are employed in the feature extraction stage to screen out the most representative PPG features, thus improving the accuracy of PPG authentication. In the experiments, we adopt eight publicly PPG/rPPG databases and our own rPPG dataset collected via a remote camera to evaluate our proposed biometric authentication system. The experimental results show that our proposed remote PPG biometric authentication system outperforms the state-of-the-art related work in terms of balancing authentication accuracy and biometric privacy protection.

Positron emission tomography (PET) is a nuclear medical imaging technique where image quality depends on the dose of radionuclides administered to the patient. While standard-dose PET (SPET) offers high-quality imaging, it also poses radiation risks. If reconstructing low-dose PET (LPET) images can guarantee the same level of imaging quality, LPET could serve as a safer alternative by reducing patient radiation exposure. Recent approaches using convolutional neural networks (CNNs) struggle to capture complex features of LPET images due to the fixed convolutional kernels and local receptive fields. Generative adversarial network (GAN)-based methods may suffer from mode collapse and unstable training. Diffusion model-based works can ensure stability and high-quality sample generation but come with high computational costs. Furthermore, all these methods focus solely on spatial domain information, neglecting crucial frequency domain information.To address these issues, we propose an efficient residual-based LPET reconstruction framework combining CNN and diffusion model. Our framework includes a multi-scale dynamic convolution network with a wavelet reconstruction module (MN-WR) to leverage multi-scale spatial and frequency domain information. We also introduce a residual-based diffusion model (ReD) to enhance local detail reconstruction while reducing computational costs. Finally, we design a wavelet-based frequency domain fusion (WFF) module to combine low-frequency edge information from MN-WR with high-frequency details from ReD. Experimental results on public LPET datasets show that our method outperforms state-of-the-art techniques and significantly reduces computational costs. Code is available at https://github.com/TAI-Medical-Lab/LPET-Reconstruction.

While deep learning models play a crucial role in predicting antibody-antigen interactions (AAI), the scarcity of publicly available sequence-structure pairings constrains their generalization. Current AAI methods often focus on residue-level static details, overlooking fine-grained structural representations of antibodies and their inter-antibody similarities. To tackle this challenge, we introduce a multi-modality representation approach that integates 3D structural and 1D sequence data to unravel intricate intra-antibody hierarchical relationships. By harnessing these representations, we present MuLAAIP, an AAI prediction framework that utilizes graph attention networks to illuminate graph-level structural features and normalized adaptive graph convolution networks to capture inter-antibody sequence associations. Furthermore, we have curated an AAI benchmark dataset comprising both structural and sequence information along with interaction labels. Through extensive experiments on this benchmark, our results demonstrate that MuLAAIP outperforms current state-of-the-art methods in terms of predictive performance. The implementation code and dataset are publicly available at https://github.com/trashTian/MuLAAIP for reproducibility.

Vision-Language Models (VLMs), with their strong reasoning and planning capabilities, are widely used in embodied decision-making (EDM) tasks in embodied agents, such as autonomous driving and robotic manipulation. Recent research has increasingly explored adversarial attacks on VLMs to reveal their vulnerabilities. However, these attacks either rely on overly strong assumptions, requiring full knowledge of the victim VLM, which is impractical for attacking VLM-based agents, or exhibit limited effectiveness. The latter stems from disrupting most semantic information in the image, which leads to a misalignment between the perception and the task context defined by system prompts. This inconsistency interrupts the VLM's reasoning process, resulting in invalid outputs that fail to affect interactions in the physical world. To this end, we propose a fine-grained adversarial attack framework, AdvEDM, which modifies the VLM's perception of only a few key objects while preserving the semantics of the remaining regions. This attack effectively reduces conflicts with the task context, making VLMs output valid but incorrect decisions and affecting the actions of agents, thus posing a more substantial safety threat in the physical world. We design two variants of based on this framework, AdvEDM-R and AdvEDM-A, which respectively remove the semantics of a specific object from the image and add the semantics of a new object into the image. The experimental results in both general scenarios and EDM tasks demonstrate fine-grained control and excellent attack performance.