Egocentric action recognition from noisy videos

学位の種別: 修士University of Tokyo(東京大学

Compound Prototype Matching for Few-shot Action Recognition

Few-shot action recognition aims to recognize novel action classes using only a small number of labeled training samples. In this work, we propose a novel approach that first summarizes each video into compound prototypes consisting of a group of global prototypes and a group of focused prototypes, and then compares video similarity based on the prototypes. Each global prototype is encouraged to summarize a specific aspect from the entire video, for example, the start/evolution of the action. Since no clear annotation is provided for the global prototypes, we use a group of focused prototypes to focus on certain timestamps in the video. We compare video similarity by matching the compound prototypes between the support and query videos. The global prototypes are directly matched to compare videos from the same perspective, for example, to compare whether two actions start similarly. For the focused prototypes, since actions have various temporal variations in the videos, we apply bipartite matching to allow the comparison of actions with different temporal positions and shifts. Experiments demonstrate that our proposed method achieves state-of-the-art results on multiple benchmarks.Comment: ECCV 202

The impact of monetary policy shocks on income inequality: a tale of two countries

The easing monetary policy after the global financial crisis triggered wide concerns on the responses of income inequality. In this paper, we investigate impact of monetary policy shocks on income inequality. We propose a general equilibrium model and show that monetary policies could affect income inequality by affecting the earnings of high-income households in financial markets and business operations. Using a TVP-FAVAR model, we find contradictory distributional effects of monetary policy shocks in China and the US. Specifically, expansionary monetary policy shocks persistently increase income inequality in China but decrease income inequality in the US. Moreover, the impacts are volatile in the short-term, but stabilise after 10 periods. The investigation on the responses of top 1% and bottom 50% income share confirms the finding of contradictory distributional effects of monetary policy shocks

Metabolism and Excretion Study of Daphnoretin in Rats after Oral Administration

The metabolism and excretion profile in rats were investigated after a single dose of daphnoretin. Metabolites of daphnoretin in rats were characterized by HPLC-MS n analysis. A HPLC-UV method was developed to determine the concentration of daphnoretin in rat urine, feces and bile. Daphnoretin was biotransformed via conjunctive and oxidative pathways to three detected metabolites. The structures of these metabolites were tentatively identified. The cumulative excretion percentage of daphnoretin in urine, feces and bile of rats was 0.13, 52.7, and 0.018 %, respectively. All the metabolites and excretion data are reported for the first time.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Metabolism and Excretion Study of Daphnoretin in Rats after Oral Administration

The metabolism and excretion profile in rats were investigated after a single dose of daphnoretin. Metabolites of daphnoretin in rats were characterized by HPLC-MS n analysis. A HPLC-UV method was developed to determine the concentration of daphnoretin in rat urine, feces and bile. Daphnoretin was biotransformed via conjunctive and oxidative pathways to three detected metabolites. The structures of these metabolites were tentatively identified. The cumulative excretion percentage of daphnoretin in urine, feces and bile of rats was 0.13, 52.7, and 0.018 %, respectively. All the metabolites and excretion data are reported for the first time.Colegio de Farmacéuticos de la Provincia de Buenos Aire

COVID-19 Shock and the Time-Varying Volatility Spillovers Among the Energy and Precious Metals Markets: Evidence From A DCC-GARCH-CONNECTEDNESS Approach

The outbreak of the COVID-19 epidemic intensified the volatility of commodity markets (the energy and precious metals markets), which created a significant negative impact on the volatility spillovers among these markets. It may also have triggered a new volatility risk contagion. In this paper, we introduce the DCC-GARCH-CONNECTEDNESS approach to explore the volatility spillover level and multi-level spillover structure characteristics among the commodity markets before and during the COVID-19 epidemic in order to clarify the new volatility risk contagion patterns across the markets. The results implied several conclusions. (i) The COVID-19 epidemic has significantly improved the total volatility spillover level of the energy and precious metals markets and has enhanced the risk connectivity among the markets. (ii) The COVID-19 epidemic has amplified the volatility of the crude oil market, making it the main volatility spillover market, namely the source of volatility risk contagion. (iii) The COVID-19 epidemic outbreak enhanced the external risk absorption capacity of the natural gas and silver markets, and the absorption level of the external volatility spillover improved significantly. Furthermore, the risk absorption capacity of the gold market weakened, while the gold market has remained the endpoint of external volatility risk during the epidemic and has acted as a risk stabilizer. (iv) The volatility spillover among markets has clear time-varying characteristics and a positive connectedness with the severity of the COVID-19 epidemic. As the severity of the COVID-19 epidemic increases, the volatility risk connectivity among the markets rapidly increases

Epithelial-Mesenchymal Transitions of Bile Duct Epithelial Cells in Primary Hepatolithiasis

The purpose of this study was to explore the role of epithelial-mesenchymal transition in the pathogenesis of hepatolithiasis. Thirty-one patients with primary hepatolithiasis were enrolled in this study. Expressions of E-cadherin, α-catenin, α-SMA, vimentin, S100A4, TGF-β1 and P-smad2/3 in hepatolithiasis bile duct epithelial cells were examined by immunohistochemistry staining. The results showed that the expressions of the epithelial markers E-cadherin and α-catenin were frequently lost in hepatolithiasis (32.3% and 25.9% of cases, respectively), while the mesenchymal markers vimentin, α-SMA and S100A4 were found to be present in hepatolithiasis (35.5%, 29.0%, and 32.3% of cases, respectively). The increased mesenchymal marker expression was correlated with decreased epithelial marker expression. The expressions of TGF-β1 and P-smad2/3 in hepatolithiasis were correlated with the expression of S100A4. These data indicate that TGF-β1-mediated epithelial-mesenchymal transition might be involved in the formation of hepatolithiasis

Neointimal hyperplasia persists at six months after sirolimus-eluting stent implantation in diabetic porcine

BACKGROUND: Observational clinical studies have shown that patients with diabetes have less favorable results after percutaneous coronary intervention compared with the non-diabetic counterparts, but its mechanism remains unclear. The aim of this study was to examine the changes of neointimal hyperplasia after sirolimus-eluting stent (SES) implantation in a diabetic porcine model, and to evaluate the impact of aortic inflammation on this proliferative process. METHODS: Diabetic porcine model was created with an intravenous administration of a single dose of streptozotocin in 15 Chinese Guizhou minipigs (diabetic group); each of them received 2 SES (Firebird, Microport Co, China) implanted into 2 separated major epicardial coronary arteries. Fifteen non-diabetic minipigs with SES implantation served as controls (control group). At 6 months, the degree of neointimal hyperplasia was determined by repeat coronary angiography, intravascular ultrasound (IVUS) and histological examination. Tumor necrosis factor (TNF)-α protein level in the aortic intima was evaluated by Western blotting, and TNF-α, interleukin (IL)-1β and IL-6 mRNA levels were assayed by reverse transcription and polymerase chain reaction. RESULTS: The distribution of stented vessels, diameter of reference vessels, and post-procedural minimal lumen diameter were comparable between the two groups. At 6-month follow-up, the degree of in-stent restenosis (40.4 ± 24.0% vs. 20.2 ± 17.7%, p < 0.05), late lumen loss (0.33 ± 0.19 mm vs. 0.10 ± 0.09 mm, p < 0.001) by quantitative angiography, percentage of intimal hyperplasia in the stented area (26.7 ± 19.2% vs. 7.3 ± 6.1%, p < 0.001) by IVUS, and neointimal area (1.59 ± 0.76 mm(2 )vs. 0.41 ± 0.18 mm(2), p < 0.05) by histological examination were significantly exacerbated in the diabetic group than those in the controls. Significant increases in TNF-α protein and TNF-α, IL-1β and IL-6 mRNA levels were observed in aortic intima in the diabetic group. CONCLUSION: Neointimal hyperplasia persisted at least up to 6 months after SES implantation in diabetic porcine, which may be partly related to an exaggerated inflammatory response within the blood vessel wall. Our results provide theoretical support for potential direct beneficial effects of anti-diabetic and anti-inflammation medications in reducing the risk of restenosis after stenting

Survival effect of PDGF-CC rescues neurons from apoptosis in both brain and retina by regulating GSK3β phosphorylation

Platelet-derived growth factor CC (PDGF-CC) is the third member of the PDGF family discovered after more than two decades of studies on the original members of the family, PDGF-AA and PDGF-BB. The biological function of PDGF-CC remains largely to be explored. We report a novel finding that PDGF-CC is a potent neuroprotective factor that acts by modulating glycogen synthase kinase 3β (GSK3β) activity. In several different animal models of neuronal injury, such as axotomy-induced neuronal death, neurotoxin-induced neuronal injury, 6-hydroxydopamine–induced Parkinson’s dopaminergic neuronal death, and ischemia-induced stroke, PDGF-CC protein or gene delivery protected different types of neurons from apoptosis in both the retina and brain. On the other hand, loss-of-function assays using PDGF-C null mice, neutralizing antibody, or short hairpin RNA showed that PDGF-CC deficiency/inhibition exacerbated neuronal death in different neuronal tissues in vivo. Mechanistically, we revealed that the neuroprotective effect of PDGF-CC was achieved by regulating GSK3β phosphorylation and expression. Our data demonstrate that PDGF-CC is critically required for neuronal survival and may potentially be used to treat neurodegenerative diseases. Inhibition of the PDGF-CC–PDGF receptor pathway for different clinical purposes should be conducted with caution to preserve normal neuronal functions