•Investment sentiment of renewable energy is constructed using Google search index.•Static and dynamic spillover of three is analysed in terms of return and volatility.•Spillover effect of volatility ...system was stronger than that of return system.•Impact of fossil energy market on renewable stock market was greater than sentiment.•Sentiment can explain return and volatility of renewable stock to a certain degree.
This study investigates the dynamic directional information spillover of return and volatility between the fossil energy market, investor sentiment towards renewable energy and the renewable energy stock market using the connectedness network approach. Empirical results show that the spillover effects of the volatility system are generally stronger than that of the return system, which suggest that risk transmission among the markets is more obvious. In both systems, the impact of the fossil energy market, especially crude oil, on the renewable energy stock market is greater than the impact of investor sentiment on the renewable energy stock market. This finding shows that the renewable energy stock market is closely related to the fossil energy market. Furthermore, the rolling window approach is adopted to examine the time-varying information spillover among them. The dynamic findings suggest that investor sentiment towards renewable energy can explain the return and volatility of renewable energy stock to a certain degree.
This paper constructs the returns and volatility system networks of the global new energy companies using the connectedness network approach. Then, it measures the information spillover direction and ...degree among the global new energy companies for the two systems, furthermore, exploring the rolling-windows estimating method to investigate the time-varying characteristics of the information spillover mechanism. It selects 20 large energy companies with a weighting greater than 1.24% from the NEX index and obtains the weekly stock prices for these companies from November 24, 2006 to January 4, 2019. Some new findings can be obtained: (1) The total information spillover degree among the global new energy companies is very high, especially for the volatility system. (2) The static and dynamic asymmetry indexes confirm the existence of asymmetric effect for the information transmission mechanism, which shows that the bad news does contribute more to the systemic risk of global new energy company stock market than the good news. (3) Some new energy companies act as net information transmitters, which are relatively important in the networks. These new findings could provide a reference for investors in the new energy sector to develop specific portfolios and risk management, as well as advise relevant policy makers.
•Returns and volatility system networks of global new energy companies are constructed.•Dynamic information spillover among global new energy companies is explored.•Total information spillover degree among global new energy companies is very high.•Asymmetric effect exists for the information transmission mechanism.•Some new energy companies acting as net transmitters are important in networks.
Major depressive disorder (MDD) is one of the most common mental disorders. We designed a fast-onset antidepressant that works by disrupting the interaction between the serotonin transporter (SERT) ...and neuronal nitric oxide synthase (nNOS) in the dorsal raphe nucleus (DRN). Chronic unpredictable mild stress (CMS) selectively increased the SERT-nNOS complex in the DRN in mice. Augmentation of SERT-nNOS interactions in the DRN caused a depression-like phenotype and accounted for the CMS-induced depressive behaviors. Disrupting the SERT-nNOS interaction produced a fast-onset antidepressant effect by enhancing serotonin signaling in forebrain circuits. We discovered a small-molecule compound, ZZL-7, that elicited an antidepressant effect 2 hours after treatment without undesirable side effects. This compound, or analogous reagents, may serve as a new, rapidly acting treatment for MDD.
Seismic time-frequency analysis methods play an important role in seismic interpretation for its superiority in significantly revealing the frequency content of a seismic signal changes with time ...variation. Variational-mode decomposition (VMD) is a newly developed methodology for decomposition on adaptive and quasi-orthogonal signal and can decompose a seismic signal into a number of band-limited quasi-orthogonal intrinsic mode functions (IMFs). Each mode is an AM-FM signal with the narrow-band property and nonnegative smoothly varying instantaneous frequencies. Analysis on synthetic and real data shows that this method is more robust to noise and has stronger local decomposition ability than the empirical mode decomposition (EMD)-based methods. Comparing with the short-time Fourier transform (STFT) or wavelet transform (WT), instantaneous spectrum after VMD promises higher spectral and spatial resolution. Application of the VMD on field data demonstrates that instantaneous spectrum after VMD targets the thickness variation in the coal seam more sensitively than the conventional tools and highlights the fine details that might escape unnoticed. The technique is more promising for seismic signal processing and interpretation.
An important pathway for biochar to alter the availability of soil phosphorus (P) is to change P sorption characteristics of the soil. The aim of this study was to understand the mechanisms of ...biochar effects on P sorption in acid upland red soils in the presence of different concentrations of exogenous P. Rice straw biochar (RSB) was prepared and applied at rates of 0, 1%, 3%, and 5% (w/w) to three red soils (MZ1, MZ2, and QY1) differing in initial pH (pH = 4.31, 4.82, and 5.68, respectively). The P sorption characteristics of these red soils were described using the Langmuir and Temkin equations and their relationships with soil basic physicochemical properties were analyzed. Furthermore, a representative red soil (MZ2) was selected to analyze the zeta potential of soil colloids and the chemical properties of sorption equilibrium solution, in order to understand their relationships with P sorption characteristics. Results showed that within a certain range of P concentration in the equilibrium solution, the amount of P sorbed by the three red soils decreased and the corresponding amount of P desorbed increased with increasing amendment rate of RSB. RSB showed the greatest effect on P desorption characteristics of MZ2 soil in the presence of higher exogenous P concentration. With increasing RSB amendment rate, the maximum P sorption of MZ1 soil decreased, while those of MZ2 and QY1 soils increased after an initial decrease. Phosphate sorption equilibrium constant and maximum P buffer capacity of each soil first increased and then decreased. However, a single physicochemical property could not interpret complex changes in multi-factors that jointly determine the P sorption characteristics of red soils. In the case of MZ2 soil, RSB amendment shifted the zeta potential of soil colloids to the negative direction; this decreased the positive charge and increased the negative charge on the soil surface, thus reducing P sorption in the MZ2 soil. In the presence of the same concentration of exogenous P, RSB amendment altered the pH, dissolved organic C (DOC), humification index (HIX), and maximum fluorescence intensity (Fmax) in the sorption equilibrium solution. In most cases, the amount of P sorbed by the MZ2 soil was negatively correlated with the pH value, DOC concentration, HIX value, and Fmax value of humic-like dissolved organic matter (DOM), and positively correlated with the Fmax value of protein-like DOM (P < 0.05 or P < 0.01). The relative fractional distribution of the contents for humic-like and protein-like DOM might determine the difference in the P sorption characteristics of MZ2 soil. In conclusion, different amendment rates of RSB affected the release of phosphate from soil surfaces into the solution by altering basic physicochemical and electrochemical properties of red soils and chemical properties of sorption equilibrium solution.
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•Three acid red soils were amended with rice straw biochar (RSB) at different rates.•RSB amendment decreased P sorption by altering soil physicochemical properties.•The increase in humic-like fluorescent dissolved organic matter decreased P sorption.•RSB amendment affected P release from soil surfaces into solution by multi-factors.
We propose a stable seismic Q estimation approach by employing quantum mechanics-based signal representation. For Q estimation, we project a seismic trace onto a specific basis composed of wave ...functions constructed through the resolution of the Schroedinger equation of non-relativistic quantum mechanics at first. Then, based on the specific basis, we derive the quantum mechanics-based Q estimation approach in the local frequency-projection coefficient domain. The Planck constant and the control factor are the two key factors for the quantum mechanics-based Q estimation method. Compared with the traditional methods, the quantum mechanics-based Q estimation approach shows more stability and noise robustness. The synthetic and field data applications illustrate the effectiveness and the superiority of the proposed method. The quantum mechanics-based Q estimation method offers a new field and provides a complementary way for measuring seismic attenuation.
A novel hydrocarbon detection technique named the variational mode decomposition (VMD)-based instantaneous centroid method is proposed in this letter. It reveals frequency-dependent amplitude ...anomalies that may reflect some details deeply buried within the intrinsic mode functions (IMFs) in particular frequency bands. Instantaneous amplitude and instantaneous frequency information from each IMF are used to generate each IMF instantaneous centroid. A weighted correlation scheme is employed to generate the VMD-based instantaneous centroid volume for a seismic trace. Model testing and field data from a carbonate reservoir in China illustrate that the VMD-based instantaneous centroid method can provide a better hydrocarbon-prone interpretation with a higher resolution and accuracy. Comparisons between the VMD-based instantaneous centroid method and the short-time Fourier transform, and continuous wavelet transform and prestack wave impedance inversion technology indicate that the proposed method is more convenient and can effectively target gas reservoirs. This letter presents a complementary approach to current methods used to extract frequency-dependent amplitude anomaly information.
Metformin, a biguanide drug, is the most commonly used first-line medication for type 2 diabetes mellites due to its outstanding glucose-lowering ability. After oral administration of 1 g, metformin ...peaked plasma concentration of approximately 20–30 μM in 3 h, and then it mainly accumulated in the gastrointestinal tract, liver and kidney. Substantial studies have indicated that metformin exerts its beneficial or deleterious effect by multiple mechanisms, apart from AMPK-dependent mechanism, also including several AMPK-independent mechanisms, such as restoring of redox balance, affecting mitochondrial function, modulating gut microbiome and regulating several other signals, such as FBP1, PP2A, FGF21, SIRT1 and mTOR. On the basis of these multiple mechanisms, researchers tried to repurpose this old drug and further explored the possible indications and adverse effects of metformin. Through investigating with clinical studies, researchers concluded that in addition to decreasing cardiovascular events and anti-obesity, metformin is also beneficial for neurodegenerative disease, polycystic ovary syndrome, aging, cancer and COVID-19, however, it also induces some adverse effects, such as gastrointestinal complaints, lactic acidosis, vitamin B12 deficiency, neurodegenerative disease and offspring impairment. Of note, the dose of metformin used in most studies is much higher than its clinically relevant dose, which may cast doubt on the actual effects of metformin on these disease in the clinic. This review summarizes these research developments on the mechanism of action and clinical evidence of metformin and discusses its therapeutic potential and clinical safety.
This article provides a general overview of local wave decomposition (LWD) methods including empirical mode decomposition (EMD), ensemble EMD, complete ensemble EMD with adaptive noise, ...synchrosqueezed transform and variational mode decomposition applied to seismic interpretation, covering the theoretical background and applications. We explain how LWD methods can be reviewed as a special and stronger case of the classical seismic time–frequency methods and place emphasis on the interest of using such LWD methods in seismic instantaneous frequency extraction, seismic attenuation estimation and seismic resolution enhancement.
Mitochondria, as the powerhouse of cells, are involved in various processes of cellular homeostasis, especially energy metabolism. The morphology of mitochondria is a critical indicator for their ...functions, referring to mitochondrial fusion and fission. Here, we performed structured illumination microscopy (SIM) to measure the mitochondrial morphology in living cells. Benefitting from its nano-scale resolution, this SIM-based strategy can quantify the fusion and fission of mitochondria with high sensitivity. Furthermore, as type 2 diabetes mellitus (T2DM) is caused by a disorder of energy substrate utilization, this strategy has the potential to study T2DM by analyzing the mitochondrial morphology of insulin-resistant (IR) cells. With SIM, we found that mitochondrial fission was increased in IR MRC-5, LO2, FHs 74 Int, and HepG2 cells but not in IR Huh7 cells with high-invasiveness ability. Furthermore, we found that metformin could inhibit mitochondrial fission in IR cells, and sorafenib could promote mitochondrial fusion in HepG2 cancer cells, especially in those IR cells. To conclude, mitochondrial fission is involved in T2DM, and cancer cells with high-invasiveness ability may be equipped with stronger resistance to energy metabolism disorder. In addition, the pharmacodynamics of metformin and sorafenib in cancer may be related to the inhibition of mitochondrial fission, especially for patients with T2DM.
