Euler-symmetric complete intersection in projective space

Euler-symmetric projective varieties, introduced by Baohua Fu and Jun-Muk Hwang in 2020, are nondegenerate projective varieties admitting many $\mathbb{C}^{\times}$-actions of Euler type. They are quasi-homogeneous and uniquely determined by their fundamental forms at a general point. In this paper, we study complete intersections in projective spaces which are Euler-symmetric. It is proven that such varieties are complete intersections of hyperquadrics and the base locus of the second fundamental form at a general point is again a complete intersection.Comment: arXiv admin note: text overlap with arXiv:1707.06764 by other author

Globally conservative solutions for the modified Camassa–Holm (MOCH) equation

In this paper, we present the globally conservative solutions to the Cauchy problem for the modified Camassa–Holm (MOCH) equation. First, we transform the equation into an equivalent semi-linear system under new variables. Second, according to the standard ordinary differential equation theory with the aid of the conservation law, we give the global solutions of the semi-linear system. Finally, returning to the original variables, we obtain the globally conservative solutions to the MOCH equation

Preventive and (Neo)Adjuvant Therapeutic Effects of Metformin on Cancer

Metformin, the first-line antidiabetic drug, has become an attractive candidate in cancer therapy since retrospective clinical investigations reported that patients with type 2 diabetes receiving metformin had lower incidence of cancer than those with other glucose lowering drugs. In line with this, preclinical studies have demonstrated that the antitumor activity of metformin could proceed through several mechanisms. Thus far, metformin has been used in cancer prevention with reduced risk as consequence and treatment of various cancers as an adjuvant or neoadjuvant drug. Thus, existing data support the beneficial effects of metformin on many types of cancers such as reducing metastasis and mortality and improving pathological responses and survival rates. However, some reports do not support this and even show adverse effects. The discrepancy may be attributed to expression levels of its transporters or genetic background. Hence, this chapter briefly reviews information on the mechanism of metformin action and summarizes both completed and ongoing clinical trials in an attempt to evaluate the value of metformin in prevention and treatment of various cancer types

Quantifying Spatiotemporal Dynamics of Solar Radiation over the Northeast China Based on ACO-BPNN Model and Intensity Analysis

Reliable information on the spatiotemporal dynamics of solar radiation plays a crucial role in studies relating to global climate change. In this study, a new backpropagation neural network (BPNN) model optimized with an Ant Colony Optimization (ACO) algorithm was developed to generate the ACO-BPNN model, which had demonstrated superior performance for simulating solar radiation compared to traditional BPNN modelling, for Northeast China. On this basis, we applied an intensity analysis to investigate the spatiotemporal variation of solar radiation from 1982 to 2010 over the study region at three levels: interval, category, and conversion. Research findings revealed that (1) the solar radiation resource in the study region increased from the 1980s to the 2000s and the average annual rate of variation from the 1980s to the 1990s was lower than that from the 1990s to the 2000s and (2) the gains and losses of solar radiation at each level were in different conditions. The poor, normal, and comparatively abundant levels were transferred to higher levels, whereas the abundant level was transferred to lower levels. We believe our findings contribute to implementing ad hoc energy management strategies to optimize the use of solar radiation resources and provide scientific suggestions for policy planning

IGN : Implicit Generative Networks

In this work, we build recent advances in distributional reinforcement learning to give a state-of-art distributional variant of the model based on the IQN. We achieve this by using the GAN model's generator and discriminator function with the quantile regression to approximate the full quantile value for the state-action return distribution. We demonstrate improved performance on our baseline dataset - 57 Atari 2600 games in the ALE. Also, we use our algorithm to show the state-of-art training performance of risk-sensitive policies in Atari games with the policy optimization and evaluation

AMPK exerts dual regulatory effects on the PI3K pathway

BACKGROUND AMP-activated protein kinase (AMPK) is a fuel-sensing enzyme that is activated when cells experience energy deficiency and conversely suppressed in surfeit of energy supply. AMPK activation improves insulin sensitivity via multiple mechanisms, among which AMPK suppresses mTOR/S6K-mediated negative feedback regulation of insulin signaling. RESULTS In the present study we further investigated the mechanism of AMPK-regulated insulin signaling. Our results showed that 5-aminoimidazole-4-carboxamide-1 ribonucleoside (AICAR) greatly enhanced the ability of insulin to stimulate the insulin receptor substrate-1 (IRS1)-associated PI3K activity in differentiated 3T3-F442a adipocytes, leading to increased Akt phosphorylation at S473, whereas insulin-stimulated activation of mTOR was diminished. In 3T3-F442a preadipocytes, these effects were attenuated by expression of a dominant negative mutant of AMPK α1 subunit. The enhancing effect of ACIAR on Akt phosphorylation was also observed when the cells were treated with EGF, suggesting that it is regulated at a step beyond IR/IRS1. Indeed, when the cells were chronically treated with AICAR in the absence of insulin, Akt phosphorylation was progressively increased. This event was associated with an increase in levels of phosphatidylinositol -3,4,5-trisphosphate (PIP3) and blocked by Wortmannin. We then expressed the dominant negative mutant of PTEN (C124S) and found that the inhibition of endogenous PTEN per se did not affect phosphorylation of Akt at basal levels or upon treatment with AICAR or insulin. Thus, this result suggests that AMPK activation of Akt is not mediated by regulating phosphatase and tensin homologue (PTEN). CONCLUSION Our present study demonstrates that AMPK exerts dual effects on the PI3K pathway, stimulating PI3K/Akt and inhibiting mTOR/S6K.National Institutes of Health (CA118918, GM057959

Novel glucose sensor based on enzymeimmobilized 81° tilted fiber grating

We demonstrate a novel glucose sensor based on an optical fiber grating with an excessively tilted index fringe structure and its surface modified by glucose oxidase (GOD). The aminopropyltriethoxysilane (APTES) was utilized as binding site for the subsequent GOD immobilization. Confocal microscopy and fluorescence microscope were used to provide the assessment of the effectiveness in modifying the fiber surface. The resonance wavelength of the sensor exhibited red-shift after the binding of the APTES and GOD to the fiber surface and also in the glucose detection process. The red-shift of the resonance wavelength showed a good linear response to the glucose concentration with a sensitivity of 0.298nm(mg/ml)-1 in the very low concentration range of 0.0∼3.0mg/ml. Compared to the previously reported glucose sensor based on the GOD-immobilized long period grating (LPG), the 81° tilted fiber grating (81°-TFG) based sensor has shown a lower thermal cross-talk effect, better linearity and higher Q-factor in sensing response. In addition, its sensitivity for glucose concentration can be further improved by increasing the grating length and/or choosing a higher-order cladding mode for detection. Potentially, the proposed techniques based on 81°-TFG can be developed as sensitive, label free and micro-structural sensors for applications in food safety, disease diagnosis, clinical analysis and environmental monitoring