COVID-19 and China commodity price jump behavior:An information spillover and wavelet coherency analysis

Jumps in commodity prices can make asset risk management challenging. This study explores the influence feature of the COVID-19 epidemic on China's commodity price jumps, using 5-min intraday high-frequency futures data of three China's commodity markets (energy, chemical, and metal) from January 23, 2020 to June 10, 2022. We find that firstly the information spillover from the COVID-19 spread situation to China's energy price jumps is relatively weak, and the COVID-19 epidemic shows the most substantial jump information spillover pattern to China's chemical price. The information spillover pattern is time-varying across the COVID-19 spread situation phase. Secondly, there are co-movement patterns between China's commodity price and China/global COVID-19 confirmed cases. This co-movement feature mainly occurs at the medium- or long-run time scales, and varies across commodities. Thirdly, the demand elasticity for China's commodities and its dependence on imports and exports are the main factors influencing the sensitivity of its price jumps to the COVID-19 outbreak

Metabolic Profiling Study of Yang Deficiency Syndrome in Hepatocellular Carcinoma by H

This study proposes a 1H NMR-based metabonomic approach to explore the biochemical characteristics of Yang deficiency syndrome in hepatocellular carcinoma (HCC) based on serum metabolic profiling. Serum samples from 21 cases of Yang deficiency syndrome HCC patients (YDS-HCC) and 21 cases of non-Yang deficiency syndrome HCC patients (NYDS-HCC) were analyzed using 1H NMR spectroscopy and partial least squares discriminant analysis (PLS-DA) was applied to visualize the variation patterns in metabolic profiling of sera from different groups. The differential metabolites were identified and the biochemical characteristics were analyzed. We found that the intensities of six metabolites (LDL/VLDL, isoleucine, lactate, lipids, choline, and glucose/sugars) in serum of Yang deficiency syndrome patients were lower than those of non-Yang deficiency syndrome patients. It implies that multiple metabolisms, mainly including lipid, amino acid, and energy metabolisms, are unbalanced or weakened in Yang deficiency syndrome patients with HCC. The decreased intensities of metabolites including LDL/VLDL, isoleucine, lactate, lipids, choline, and glucose/sugars in serum may be the distinctive metabolic variations of Yang deficiency syndrome patients with HCC. And these metabolites may be potential biomarkers for diagnosis of Yang deficiency syndrome in HCC

The Main Progress of Perovskite Solar Cells in 2020–2021

Perovskite solar cells (PSCs) emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world. Both the efficiency and stability of PSCs have increased steadily in recent years, and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step. This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency, stability, perovskite-based tandem devices, and lead-free PSCs. Moreover, a brief discussion on the development of PSC modules and its challenges toward practical application is provided

Combined Removal of Sr2+ by Montmorillonite-carbonate Mineralizing Bacteria

Adsorption and biomineralisation are two important methods in the treatment of various radioactive heavy metal pollution. Among them, adsorption is considered by researchers as one of the most promising methods for the treatment of heavy metal wastewater due to its lower cost and better treatment effect, while biomineralisation is one of the hot spots of research at home and abroad today for its environmental friendliness and high operability. However, the combination of these two approaches in some way will be significant in expanding the treatment of radioactive heavy metal contaminated wastewater. In this work, a typical clay mineral, montmorillonite, a mineralising microorganism, carbonate mineralising bacteria and the radioactive heavy metal ion Sr2+ were selected as the objects of study, and a montmorillonitecarbonate mineralising bacteria composite system was constructed. The combined effect of clay minerals and microorganisms on the removal of Sr2+ was investigated by comparing the pH, carbonate concentration, Sr2+ concentration in the liquid phase and its fugitive state with time under the influence of montmorillonite and the constructed composite system of montmorillonitecarbonate mineralising bacteria, respectively. The results show that montmorillonite and carbonate mineralizing bacteria can remove Sr2+ through adsorption and microbial mineralization, respectively. In a single adsorption system, the removal rate of Sr2+ in liquid phase is proportional to the dosage of montmorillonite. In the constructed complex system, montmorillonite and carbonate mineralizing bacteria play different roles at different time and the overall effect of montmorillonite on Sr2+ adsorption decreases with increasing time, while the mineralizing effect of carbonate mineralizing bacteria increases with increasing time, that is to say, in the whole process of Sr2+ removal, the adsorption effect of montmorillonite is dominant in the early stage of the experiment, and the mineralizing effect of carbonate mineralizing bacteria is dominant in the later stage. The results of XRD and FT-IR analysis of the sediment at the end of the experiment show the formation of strontium carbonate precipitation, which verifies that carbonate mineralizing bacteria can achieve removal of Sr2+ through biomineralization. Under the liquid phase environmental conditions with the montmorillonite dosage of 40 g/L and the initial Sr2+ concentration of 1 10019 mg/L, the highest removal rate of Sr2+ by the montmorillonite single adsorption system is only 2848%, while the removal rate of Sr2+ by the constructed montmorillonitecarbonate mineralizing bacteria composite system is as high as 9792%. Therefore, compared with the traditional single montmorillonite adsorption system, the constructed montmorillonitecarbonate mineralizing bacteria composite system can effectively achieve the removal of Sr2+. Based on the adsorption of clay minerals and the biomineralization of microorganisms, the montmorillonitecarbonate mineralising bacteria composite system constructed in this study provides a reference for the future treatment of Sr2+ radioactive contaminated wastewater

The tail risk safe haven property of China's energy futures against US market implied volatility

This paper analyses the tail risk contagion of US market implied volatility (USIV) on China's energy futures (CEF) markets, exploring how to utilize operations in the CEF to achieve a safe haven. Leveraging CEF characteristics to simultaneously take both long-/short-positions and engage in long-/short-run investment horizons, this paper defines eight different CEF safe haven attributes to counteract the tail risk of extreme increases in USIV. Using trading data from March 27, 2018, to October 30, 2023, the empirical results show that, first, in the analysis of the entire sample period, China's coking coal futures can serve as a weak safe haven, aiding long-position investors in mitigating the tail risks associated with US gold and stock market implied volatility. Coking coal futures also assist short-position investors in countering US stock market implied volatility tail risk. Second, in the sub-period analysis, the safe haven attributes of CEF exhibit strong heterogeneity and asymmetry across different periods. Finally, the time span during which CEF exhibits a particular safe haven attribute does not persist for an extended period

Do weather conditions drive China's carbon-coal-electricity markets systemic risk? A multi-timescale analysis

This paper uses the wavelet coherency method to reveal the timescale-varying driving mechanism of 12 different types of weather conditions data on risk measures of China's Carbon-Coal-Electricity (CCE) system. First, we find that temperature may be a major factor influencing the co-movement pattern of China's CCE system on a long-term timescale, but cannot affect information spillover pattern of the CCE system. Second, snowfall, cloud, and wind levels could influence the long-term variation of the CCE system's risk measurement. Third, none of the selected weather condition indicators could influence the short- and medium-run CCE systemic risk

Screening and Identification of a Strain of Heterotrophic Nitrification Bacteria and Its Application in Wastewater Treatment of Rural Farming

【Objective】Aiming at the problem of being difficult to treat the high concentration of NH4+-N in farming wastewater, one heterotrophic nitrification bacterium was isolated and screened from the lake sediment.【Method】The screened strains were subjected to Gram staining, scanning electron microscopy and strain identification. Homology analysis of 16SrDNA sequencing results was performed in the Blast database and phylogenetic trees were constructed. The heterotrophic nitrification and aerobic denitrification properties of this strain under different nitrogen sources were studied, and the denitrification characteristics were studied with different inoculum levels, carbon source, initial pH, temperature, C/N, and initial NH4+-N concentration as environmental factors. Finally, the strain was added to the actual rural pig wastewater to evaluate its application ability.【Result】The strain of heterotrophic nitrification strain was identified as Acinetobacter sp and named L-1. Univariate experiments showed that L-1 had the best heterotrophic nitrification effect under inoculation ratio of 2%, carbon source of sodium citrate, pH 6-9, temperature 20-30 ℃, C/N 10-20, and NH4+-N initial concentration of 50 mg/L. In the actual pig wastewater, L-1 was added to the wastewater for nitrogen removal, in which the 1 000 mg/L NH4+-N wastewater was reduced to 298.46 mg/L at the 96th hour. The removal rate of NH4+-N reached 70.15%, which was 45.78% higher than that of the blank control group, while both concentrations of NO3--N and NO2--N were decreased.【Conclusion】The strain L-1 has the ability of heterotrophic nitrification and aerobic denitrification, which has certain reference value in the study of heterotrophic nitrification bacteria for the treatment of pig wastewater

Nanotheranostics: Congo Red/Rutin-MNPs with Enhanced Magnetic Resonance Imaging and H2O2-Responsive Therapy of Alzheimer's Disease in APPswe/PS1dE9 Transgenic Mice

As nanotheranostics, Congo red/Rutin-MNPs combine the abilities of diagnosis and treatment of Alzheimer&#39;s disease (AD). The biocompatible nanotheranostics system based on iron oxide magnetic nanoparticles, with ultrasmall size and excellent magnetic properties, can specifically detect amyloid plaques by magnetic resonance imaging, realize targeted delivery of AD therapeutic agents, achieve drug controlled release by H2O2 response, and prevent oxidative stress.</p