LogoStyleFool: Vitiating Video Recognition Systems via Logo Style Transfer

Video recognition systems are vulnerable to adversarial examples. Recent studies show that style transfer-based and patch-based unrestricted perturbations can effectively improve attack efficiency. These attacks, however, face two main challenges: 1) Adding large stylized perturbations to all pixels reduces the naturalness of the video and such perturbations can be easily detected. 2) Patch-based video attacks are not extensible to targeted attacks due to the limited search space of reinforcement learning that has been widely used in video attacks recently. In this paper, we focus on the video black-box setting and propose a novel attack framework named LogoStyleFool by adding a stylized logo to the clean video. We separate the attack into three stages: style reference selection, reinforcement-learning-based logo style transfer, and perturbation optimization. We solve the first challenge by scaling down the perturbation range to a regional logo, while the second challenge is addressed by complementing an optimization stage after reinforcement learning. Experimental results substantiate the overall superiority of LogoStyleFool over three state-of-the-art patch-based attacks in terms of attack performance and semantic preservation. Meanwhile, LogoStyleFool still maintains its performance against two existing patch-based defense methods. We believe that our research is beneficial in increasing the attention of the security community to such subregional style transfer attacks.Comment: 14 pages, 3 figures. Accepted to AAAI 202

Neutrophil Extracellular Traps Formation and Aggregation Orchestrate Induction and Resolution of Sterile Crystal-Mediated Inflammation

The formation of neutrophil extracellular traps (NETs) to immobilize pathogens represents a novel antimicrobial strategy of the immune system. The microcrystals related to human diseases are classified into endogenous microcrystals, including monosodium urate (MSU), calcium pyrophosphate dihydrate, calcium carbonate, calcium phosphate, calcium oxalate, cholesterol, and exogenous material like crystals from silica. Although microcrystals possess distinct compositions and shapes, they have a common characteristic: they stimulate neutrophils to release NETs. In low and high densities, neutrophils form NETs and aggregated NETs (aggNETs) that reportedly orchestrate the initiation and resolution of sterile crystal-mediated inflammation, respectively. Here, we summarize the different roles of NETs and aggNETs stimulated by the crystals mentioned above in related inflammatory reactions. The NETosis-derived products may represent a potential therapeutic target in crystal-mediated diseases

Matrix inverses along the core parts of three matrix decompositions

New characterizations for generalized inverses along the core parts of three matrix decompositions were investigated in this paper. Let $A_{1}$, $\hat{A}_{1}$ and $\tilde{A}_{1}$ be the core parts of the core-nilpotent decomposition, the core-EP decomposition and EP-nilpotent decomposition of $A\in \mathbb{C}^{n\times n}$, respectively, where EP denotes the EP matrix. A number of characterizations and different representations of the Drazin inverse, the weak group inverse and the core-EP inverse were given by using the core parts $A_{1}$, $\hat{A}_{1}$ and $\tilde{A}_{1}$. One can prove that, the Drazin inverse is the inverse along $A_{1}$, the weak group inverse is the inverse along $\hat{A}_{1}$ and the core-EP inverse is the inverse along $\tilde{A}_{1}$. A unified theory presented in this paper covers the Drazin inverse, the weak group inverse and the core-EP inverse based on the core parts of the core-nilpotent decomposition, the core-EP decomposition and EP-nilpotent decomposition of $A\in \mathbb{C}^{n\times n}$, respectively. In addition, we proved that the Drazin inverse of $A$ is the inverse of $A$ along $U$ and $A_{1}$ for any $U\in \{A_{1}, \hat{A}_{1}, \tilde{A}_{1}\}$; the weak group inverse of $A$ is the inverse of $A$ along $U$ and $\hat{A}_{1}$ for any $U\in \{A_{1}, \hat{A}_{1}, \tilde{A}_{1}\}$; the core-EP inverse of $A$ is the inverse of $A$ along $U$ and $\tilde{A}_{1}$ for any $U\in \{A_{1}, \hat{A}_{1}, \tilde{A}_{1}\}$. Let $X_{1}$, $X_{4}$ and $X_{7}$ be the generalized inverses along $A_{1}$, $\hat{A}_{1}$ and $\tilde{A}_{1}$, respectively. In the last section, some useful examples were given, which showed that the generalized inverses $X_{1}$, $X_{4}$ and $X_{7}$ were different generalized inverses. For a certain singular complex matrix, the Drazin inverse coincides with the weak group inverse, which is different from the core-EP inverse. Moreover, we showed that the Drazin inverse, the weak group inverse and the core-EP inverse can be the same for a certain singular complex matrix

Switching fractioned R-CHOP cycles to standard r-chop cycles guided by endoscopic ultrasonography in treating patients with primary gastric diffuse large B-cell lymphoma

© 2020 Liu et al. Background: Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is a common subtype of extranodal non-Hodgkin lymphoma (NHL), with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) as the commonly used treatment regimen. However, full cycles of standard R-CHOP present the risk of severe bleeding or perforation, even leading to emergency surgery, especially for those with deep lesions in their first 1–2 cycles of treatment. This study aims to explore the safety and efficacy of fractioned R-CHOP (rituximab d0, 50% dose of CHOP d1 and d5) followed by standard R-CHOP cycles in PG-DLBCL patients guided by endoscopic ultrasonography (EUS). Patients and Methods: Thirty-one PG-DLBCL patients were analyzed in this retrospective study. All patients had lesions infiltrated to at least the 3rd layer of the stomach under EUS at baseline. Patients switched to standard R-CHOP if they showed the reduced infiltrated layers and restricted lesions after fractioned R-CHOP cycles. Results: The overall response rate, 5-year progression-free survival (PFS) and overall survival (OS) of patients in our study were 93.5%, 75% and 84%, respectively. No treatment delay or dosage reduction from gastric adverse event was observed. None of the patients in our study suffered from severe bleeding or perforation during the treatment. Kaplan–Meier analyses showed that PG-DLBCL patients characterized by multiple localization, lesions ≥3cm, having B symptoms, lower serum albumin level, and elevated LDH level were associated with worse PFS and OS. Conclusion: Our data indicate that it might be an effective approach in treating deeply infiltrated PG-DLBCL patients by switching fractioned R-CHOP to standard R-CHOP cycles guided by EUS