Diffusion-based methodologies have shown significant potential in blind face restoration (BFR), leveraging their robust generative capabilities. However, they are often criticized for two significant problems: 1) slow training and inference speed, and 2) inadequate recovery of fine-grained facial details. To address these problems, we propose a novel Truncated Diffusion model for efficient Blind Face Restoration (TD-BFR), a three-stage paradigm tailored for the progressive resolution of degraded images. Specifically, TD-BFR utilizes an innovative truncated sampling method, starting from low-quality (LQ) images at low resolution to enhance sampling speed, and then introduces an adaptive degradation removal module to handle unknown degradations and connect the generation processes across different resolutions. Additionally, we further adapt the priors of pre-trained diffusion models to recover rich facial details. Our method efficiently restores high-quality images in a coarse-to-fine manner and experimental results demonstrate that TD-BFR is, on average, 4.75× faster than current state-of-the-art diffusion-based BFR methods while maintaining competitive quality.

The breakthrough in cryo-electron microscopy (cryo-EM) technology has led to an increasing number of density maps of biological macromolecules. However, constructing accurate protein complex atomic structures from cryo-EM maps remains a challenge. In this study, we extend our previously developed DEMO-EM to present DEMO-EM2, an automated method for constructing protein complex models from cryo-EM maps through an iterative assembly procedure intertwining chain- and domain-level matching and fitting for predicted chain models. The method was carefully evaluated on 27 cryo-electron tomography (cryo-ET) maps and 16 single-particle EM maps, where DEMO-EM2 models achieved an average TM-score of 0.92, outperforming those of state-of-the-art methods. The results demonstrate an efficient method that enables the rapid and reliable solution of challenging cryo-EM structure modeling problems.

Blind face restoration usually synthesizes degraded low-quality data with a pre-defined degradation model for training, while more complex cases could happen in the real world. This gap between the assumed and actual degradation hurts the restoration performance where artifacts are often observed in the output. However, it is expensive and infeasible to include every type of degradation to cover real-world cases in the training data. To tackle this robustness issue, we propose Diffusion-based Robust Degradation Remover (DR2) to first transform the degraded image to a coarse but degradation-invariant prediction, then employ an enhancement module to restore the coarse prediction to a high-quality image. By leveraging a well-performing denoising diffusion probabilistic model, our DR2 diffuses input images to a noisy status where various types of degradation give way to Gaussian noise, and then captures semantic information through iterative denoising steps. As a result, DR2 is robust against common degradation (e.g. blur, resize, noise and compression) and compatible with different designs of enhancement modules. Experiments in various settings show that our framework outperforms state-of-the-art methods on heavily degraded synthetic and real-world datasets.

Due to the broadcast feature of the wireless channels, users are easily eavesdropped by eavesdroppers during data transmission, resulting in data leakage. To ensure the Device-to-device (D2D) communications security, in this paper, we propose a UAV-assisted secure communication system where a mobile UAV can transmit the jamming signal to counter the ground eavesdropper to enhance the security of communication. We develop a connection outage probability model to ensure the continuous communication and derive the closed form expression of the connection outage probability for D2D users. We formulated a secrecy rate maximization problem by jointly optimizing UAV’s trajectory and jamming power, in which, the secrecy rate is defined as the difference between the transmission rate and the eavesdropping rate. To solve it, we propose a TD3-based algorithm to optimize the UAV’s trajectory and jamming power. Simulation results illustrate that the overall average secrecy rate of D2D users achieved by our proposed algorithm outperforms other baselines.

Abstract Automatic generation of calligraphy fonts has attracted broad attention of researchers. However, previous font generation research mainly focused on the known font style imitation based on image to image translation. For poor interpretability, it is hard for deep learning to create new fonts with various font styles and features according to human understanding. To address this issue, the font fusion network based on generative adversarial networks (GANs) and disentangled representation learning is proposed in this paper to generate brand new fonts. It separates font into two understandable disentangled features: stroke style and skeleton shape. According to personal preferences, various new fonts with multiple styles can be generated by fusing the stroke style and skeleton shape of different fonts. First, this task improves the interpretability of deep learning, and is more challenging than simply imitating font styles. Second, considering the robustness of the network, a fuzzy supervised learning skill is proposed to enhance the stability of the fusion of two fonts with considerable discrepancy. Finally, instead of retraining, the authors' trained model can be quickly transferred to other font fusion samples. It improves the efficiency of the model. Qualitative and quantitative results demonstrate that the proposed method is capable of efficiently and stably generating the new font images with multiple styles. The source code and the implementation details of our model are available at https://github.com/Qinmengxi/Fontfusion .

SUMMARY: Evaluation of the capacity for separating actives from challenging decoys is a crucial metric of performance related to molecular docking or a virtual screening workflow. The Directory of Useful Decoys (DUD) and its enhanced version (DUD-E) provide a benchmark for molecular docking, although they only contain a limited set of decoys for limited targets. DecoyFinder was released to compensate the limitations of DUD or DUD-E for building target-specific decoy sets. However, desirable query template design, generation of multiple decoy sets of similar quality, and computational speed remain bottlenecks, particularly when the numbers of queried actives and retrieved decoys increases to hundreds or more. Here, we developed a program suite called RApid DEcoy Retriever (RADER) to facilitate the decoy-based assessment of virtual screening. This program adopts a novel database-management regime that supports rapid and large-scale retrieval of decoys, enables high portability of databases, and provides multifaceted options for designing initial query templates from a large number of active ligands and generating subtle decoy sets. RADER provides two operational modes: as a command-line tool and on a web server. Validation of the performance and efficiency of RADER was also conducted and is described. AVAILABILITY AND IMPLEMENTATION: RADER web server and a local version are freely available at http://rcidm.org/rader/ . CONTACT: [email protected] or [email protected] . SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.