Revisiting Classifier: Transferring Vision-Language Models for Video Recognition

Transferring knowledge from task-agnostic pre-trained deep models for downstream tasks is an important topic in computer vision research. Along with the growth of computational capacity, we now have open-source vision-language pre-trained models in large scales of the model architecture and amount of data. In this study, we focus on transferring knowledge for video classification tasks. Conventional methods randomly initialize the linear classifier head for vision classification, but they leave the usage of the text encoder for downstream visual recognition tasks undiscovered. In this paper, we revise the role of the linear classifier and replace the classifier with the different knowledge from pre-trained model. We utilize the well-pretrained language model to generate good semantic target for efficient transferring learning. The empirical study shows that our method improves both the performance and the training speed of video classification, with a negligible change in the model. Our simple yet effective tuning paradigm achieves state-of-the-art performance and efficient training on various video recognition scenarios, i.e., zero-shot, few-shot, general recognition. In particular, our paradigm achieves the state-of-the-art accuracy of 87.8% on Kinetics-400, and also surpasses previous methods by 20~50% absolute top-1 accuracy under zero-shot, few-shot settings on five popular video datasets. Code and models can be found at https://github.com/whwu95/Text4Vis .Comment: Accepted by AAAI-2023. Camera Ready Versio

What Can Simple Arithmetic Operations Do for Temporal Modeling?

Temporal modeling plays a crucial role in understanding video content. To tackle this problem, previous studies built complicated temporal relations through time sequence thanks to the development of computationally powerful devices. In this work, we explore the potential of four simple arithmetic operations for temporal modeling. Specifically, we first capture auxiliary temporal cues by computing addition, subtraction, multiplication, and division between pairs of extracted frame features. Then, we extract corresponding features from these cues to benefit the original temporal-irrespective domain. We term such a simple pipeline as an Arithmetic Temporal Module (ATM), which operates on the stem of a visual backbone with a plug-andplay style. We conduct comprehensive ablation studies on the instantiation of ATMs and demonstrate that this module provides powerful temporal modeling capability at a low computational cost. Moreover, the ATM is compatible with both CNNs- and ViTs-based architectures. Our results show that ATM achieves superior performance over several popular video benchmarks. Specifically, on Something-Something V1, V2 and Kinetics-400, we reach top-1 accuracy of 65.6%, 74.6%, and 89.4% respectively. The code is available at https://github.com/whwu95/ATM.Comment: Accepted by ICCV 202

Reinforcement Learning with Stepwise Fairness Constraints

AI methods are used in societally important settings, ranging from credit to employment to housing, and it is crucial to provide fairness in regard to algorithmic decision making. Moreover, many settings are dynamic, with populations responding to sequential decision policies. We introduce the study of reinforcement learning (RL) with stepwise fairness constraints, requiring group fairness at each time step. Our focus is on tabular episodic RL, and we provide learning algorithms with strong theoretical guarantees in regard to policy optimality and fairness violation. Our framework provides useful tools to study the impact of fairness constraints in sequential settings and brings up new challenges in RL.Comment: Fairness, Reinforcement Learnin

Vasorelaxant Effect of a New Hydrogen Sulfide-Nitric Oxide Conjugated Donor in Isolated Rat Aortic Rings through cGMP Pathway

Endothelium-dependent vasorelaxant injury leads to a lot of cardiovascular diseases. Both hydrogen sulfide (H2S) and nitric oxide (NO) are gasotransmitters, which play a critical role in regulating vascular tone. However, the interaction between H2S and NO in vasorelaxation is still unclear. ZYZ-803 was a novel H2S and NO conjugated donor developed by H2S-releasing moiety (S-propyl-L-cysteine (SPRC)) and NO-releasing moiety (furoxan). ZYZ-803 could time- and dose-dependently relax the sustained contraction induced by PE in rat aortic rings, with potencies of 1.5- to 100-fold greater than that of furoxan and SPRC. Inhibition of the generations of H2S and NO with respective inhibitors abolished the vasorelaxant effect of ZYZ-803. ZYZ-803 increased cGMP level and the activity of vasodilator stimulated phosphoprotein (VASP) in aortic rings, and those effects could be suppressed by the inhibitory generation of H2S and NO. Both the inhibitor of protein kinase G (KT5823) and the inhibitor of KATP channel (glibenclamide) suppressed the vasorelaxant effect of ZYZ-803. Our results demonstrated that H2S and NO generation from ZYZ-803 cooperatively regulated vascular tone through cGMP pathway, which indicated that ZYZ-803 had therapeutic potential in cardiovascular diseases

Biological function and regulation mechanism of MTA2 expression in bladder cancer

Bladder cancer that occurs on the bladder mucosa is the most common malignant tumor in the urinary system. Exposure to aromatic amine chemicals and cigarette smoking are the two risk factors which causes bladder cancer. The mechanism of complex molecular signaling during its progress is still not understood clearly. High expression of metastasis associated gene 2 (MTA2) in malignant tumors such as ovarian cancer and hepatocellular carcinoma indicates its possible relationship with migration and invasion. However, expression level and biological function of MTA2 in bladder cancer tissues have not been studied. Here, we investigated the biological function, regulation mechanism and clinical application of metastasisrelated genes 2 (MTA2). The expression level of MTA2 in various bladder tumor cells was determined by Western Blot. T24 and EJ cells were selected for in vitro study. T24 cells and EJ cells were transfected with viral vector and SiMTA2, respectively, to induce MTA2 over- or low- expression. MTS colorimetric assay was used to explore the proliferative ability of bladder cancer cells in vitro under MTA2 over- or low-expression. Matrigel invasion assay and Transwell migration assay were used to detect the invasion and migration of cancer cells in vitro under different MTA2 expression conditions. The results of Western Blot assay on bladder cancer cell lines have shown that the MTA2expression level to be significantly lower in T24 cells compared to that of EJ and J82 cells. MTA2 level was significantly higher in MTA2 overexpressed T24 cells than those in the non-transfected and CD511B transfected bladder cancer cells, while the level of MTA2 was much lower in the MTA2-knockdown EJ cells than that in the non-transfected and si-NC transfected. The MTS colorimetric assay significant increase in proliferation of T24 cells with MTA2 overexpression, while the proliferation of EJ cells with MTA2 knockdown was decreased. Results of Transwell migration assay showed that MTA2 overexpression could significantly increase the migration ability of T24 cells, and MTA2 knockdown could significantly reduce the migration ability of EJ cells. Matrigel invasion assay showed that MTA2 overexpression could enhance the invasive ability of T24 cells significantly, while MTA2 knockdown weaken the invasive ability of EJ cells. The expression level of E-cadherin was lower in the T24 cells with MTA2 overexpression than that in the non-transfected group and CD511B transfected group, but the expression level of N-cadherin protein was significantly higher in the T24 cells with MTA2 overexpression compared to the other two groups. The expression level of E-cadherin protein was significantly higher in the EJ cells with MTA2 knockdown than that of the non-transfected group and si-NC transfected group, while the expression level of N-cadherin protein was significantly lower than that in the non-transfected group and si-NC transfected group

Biological function and regulation mechanism of MTA2 expression in bladder cancer

711-716Bladder cancer that occurs on the bladder mucosa is the most common malignant tumor in the urinary system. Exposure to aromatic amine chemicals and cigarette smoking are the two risk factors which causes bladder cancer. The mechanism of complex molecular signaling during its progress is still not understood clearly. High expression of metastasis associated gene 2 (MTA2) in malignant tumors such as ovarian cancer and hepatocellular carcinoma indicates its possible relationship with migration and invasion. However, expression level and biological function of MTA2 in bladder cancer tissues have not been studied. Here, we investigated the biological function, regulation mechanism and clinical application of metastasisrelated genes 2 (MTA2). The expression level of MTA2 in various bladder tumor cells was determined by Western Blot. T24 and EJ cells were selected for in vitro study. T24 cells and EJ cells were transfected with viral vector and SiMTA2, respectively, to induce MTA2 over- or low- expression. MTS colorimetric assay was used to explore the proliferative ability of bladder cancer cells in vitro under MTA2 over- or low-expression. Matrigel invasion assay and Transwell migration assay were used to detect the invasion and migration of cancer cells in vitro under different MTA2 expression conditions. The results of Western Blot assay on bladder cancer cell lines have shown that the MTA2expression level to be significantly lower in T24 cells compared to that of EJ and J82 cells. MTA2 level was significantly higher in MTA2 overexpressed T24 cells than those in the non-transfected and CD511B transfected bladder cancer cells, while the level of MTA2 was much lower in the MTA2-knockdown EJ cells than that in the non-transfected and si-NC transfected. The MTS colorimetric assay significant increase in proliferation of T24 cells with MTA2 overexpression, while the proliferation of EJ cells with MTA2 knockdown was decreased. Results of Transwell migration assay showed that MTA2 overexpression could significantly increase the migration ability of T24 cells, and MTA2 knockdown could significantly reduce the migration ability of EJ cells. Matrigel invasion assay showed that MTA2 overexpression could enhance the invasive ability of T24 cells significantly, while MTA2 knockdown weaken the invasive ability of EJ cells. The expression level of E-cadherin was lower in the T24 cells with MTA2 overexpression than that in the non-transfected group and CD511B transfected group, but the expression level of N-cadherin protein was significantly higher in the T24 cells with MTA2 overexpression compared to the other two groups. The expression level of E-cadherin protein was significantly higher in the EJ cells with MTA2 knockdown than that of the non-transfected group and si-NC transfected group, while the expression level of N-cadherin protein was significantly lower than that in the non-transfected group and si-NC transfected group

Anti-hypercholesterolemic Effects and a Good Safety Profile of SCM-198 in Animals: From ApoE Knockout Mice to Rhesus Monkeys

Although several lipid-lowering agents have been introduced for the treatment of atherosclerosis (AS), currently marketed medications have not solved the problem completely. This study aims to investigate the effects of leonurine (SCM-198) on dyslipidemia in mammals with ApoE knockout (ApoE-/-) mice, New Zealand white rabbits and senile Rhesus monkeys fed with high fat diet were dosed daily with leonurine or atorvastatin. The serum total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL), and high-density lipoprotein (HDL) were determined. Moreover, in Rhesus monkeys, bodyweight, arterial ultrasound of right common carotid artery, Apolipoprotein A1 (ApoA1) and ApoB levels, hematologic and toxicological examinations were detected. Serum TC and TG in both mice and rabbits were significantly reduced by SCM-198 and atorvastatin. In the 10 mg/kg SCM-198 group of monkeys, maximum TC reduction of 24.05% was achieved at day 150, while 13.16% LDL reduction achieved at day 60, without arterial morphologic changes or adverse events. Atorvastatin (1.2 mg/kg) showed similar effects as SCM-198 in improving lipid profiles in monkeys, yet its long-term use could induce tolerance. Furthermore, leonurine suppressed genes expression of fatty acid synthesis, such as fatty acid synthase (FASN), stearoyl-CoA desaturase (SCD-1), sterol regulatory element-binding protein (SREBF) in liver in high fat diet feeding ApoE-/- mice. SCM-198, with a reliable safety profile, is of high value in improving lipid profiles in mammals, providing an alternative to a substantial population who are statin-intolerant