In this paper, we model the knowledge graph by constructing the new mechanism of tax collection and administration under the empowerment of IoT technology and give the knowledge subgraph and ...operation of the new mechanism of tax collection and administration. For the knowledge element extraction of the new mechanism of tax collection and administration, a dual-attention mechanism knowledge extraction model is constructed based on TransH coding and sentence feature attention model. Experiments on knowledge element extraction of the new mechanism of tax collection and administration are conducted for the model constructed in this paper. The results show that the model in this paper improves by 12.32%, 14.95% and 13.38% in accuracy, recall and F1 value, respectively, compared with the BiLSTM-CRF model. The model employed in this paper is effective in extracting the knowledge elements of the new tax collection and administration mechanism constructed based on the knowledge graph.
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•Fermentation and enzymes hydrolysis (FE) increased total phenolic content of GLT.•Soluble and insoluble-bound forms of phenolics were analyzed by HPLC.•FE processing gave the ...greatest yields of quercetin and kaempferol from GLT.•FE processing upgraded the antioxidant and α-glucosidase inhibition activity of GLT.
There are both soluble and insoluble-bound forms of phenolics in tea-leaf products. In order to increase total soluble phenolics contents, guava leaves tea (GLT) was first fermented with Monascus anka and Saccharomyces cerevisiae, and then hydrolyzed with complex enzymes. The changes in phenolics profiles, antioxidant activities and inhibitory effect on α-glucosidase in processed GLT were investigated. Compared with the un-fermented GLT, fermentation and complex enzymatic processing (FE) significantly increased the total phenolics, total flavonoids, quercetin and kaempferol contents by 2.1, 2.0, 13.0 and 6.8 times, respectively. After the FE, a major proportion of phenolics existed in the soluble form. Quercetin was released in the highest amount among different phenolics. In addition, soluble phenolic extracts from GLT following FE exhibited a highest antioxidant activity and inhibitory effect on α-glucosidase. The paper suggested an improved method for processing GLT into high-value products rich in phenolics and flavonoids aglycones with enhanced health benefits.
Due to the toxicity of petroleum compounds, the increasing accidents of marine oil spills/leakages have had a significant impact on our environment. Recently, different remedial techniques for the ...treatment of marine petroleum pollution have been proposed, such as bioremediation, controlled burning, skimming, and solidifying. (Hedlund and Staley in Int J Syst Evol Microbiol 51:61–66, 2001). This review introduces an important remedial method for marine oil pollution treatment—bioremediation technique—which is considered as a reliable, efficient, cost-effective, and eco-friendly method. First, the necessity of bioremediation for marine oil pollution was discussed. Second, this paper discussed the species of oil-degrading microorganisms, degradation pathways and mechanisms, the degradation rate and reaction model, and the factors affecting the degradation. Last, several suggestions for the further research in the field of marine oil spill bioremediation were proposed.
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•Ultrasonic conditions significantly affect extraction efficiency.•Guava leaf polysaccharides (GLP) has good antioxidant activity.•GLP exhibits remarkable hypoglycemic activity in ...vitro.
Plant polysaccharides possess multiple physiological activities. Box-Behnken design (BBD) was employed to optimize the ultrasound-assisted extraction of polysaccharides from guava leaves (GLP). It was found that ultrasonic time, temperature and power has a significant effect on the extraction efficiency. The yield of GLP was 1.00 ± 0.04% under the optimal condition of extraction time of 20 min, temperature of 62 ℃ and ultrasound power of 404 W. The DPPH and ABTS+ radical scavenging rate of GLP was 56.38% and 51.73% at 100 μg/mL, respectively. The rate of inhibition of α-amylase by GLP was only 14.06% at 1 mg/mL; however, its α-glucosidase inhibition rate reached 99.54% at 100 μg/mL. These results suggested that the ultrasound-assisted extraction for GLP is effective and environmentally friendly and GLP has wide application potentials as natural antioxidants and α-glucosidase inhibitors.
A generic small-signal model of modular multilevel converter (MMC) based DC grid is established and a DC virtual impedance damping control to suppress the resonance and instability is proposed. The ...averaged-value model (AVM) of MMC is employed to derive the Thévenin equivalent model of the converter from its DC side using the power-balancing principle considering the dynamics of phase-locked loop (PLL) of the interconnected ac system. The single section π-typed line model is selected to develop the nodal admittance equations of the DC network in s domain. The stability criterion of the DC grid is given after establishing the generic linearization model. The key factors affecting the DC grid's stability are identified using the root locus method and participation factors analysis. The parameters and the performances of the damping controller are designed and studied. Electromagnetic transient simulation model and RT-LAB real-time simulation are used to validate that the proposed damping control can suppress the instability of the DC grid and improve its operating performance.
Phenolics in food and fruit tree leaves exist in free, soluble-conjugate, and insoluble-bound forms. In this study, in order to enhance the bioavailability of insoluble-bound phenolics from guava ...leaves (GL), the ability of enzyme-assisted extraction in improving the release of insoluble-bound phenolics was investigated. Compared to untreated GL, single xylanase-assisted extraction did not change the composition and yield of soluble phenolics, whereas single cellulase or
-glucosidase-assisted extraction significantly enhanced the soluble phenolics content of PGL. However, complex enzyme-assisted extraction (CEAE) greatly improved the soluble phenolics content, flavonoids content, ABTS, DPPH, and FRAP by 103.2%, 81.6%, 104.4%, 126.5%, and 90.3%, respectively. Interestingly, after CEAE, a major proportion of phenolics existed in the soluble form, and rarely in the insoluble-bound form. Especially, the contents of quercetin and kaempferol with higher bio-activity were enhanced by 3.5- and 2.2-fold, respectively. More importantly, total soluble phenolics extracts of GL following CEAE exhibited the highest antioxidant activity and protective effect against supercoiled DNA damage. This enzyme-assisted extraction technology can be useful for extracting biochemical components from plant matrix, and has good potential for use in the food and pharmaceutical industries.
In this letter, we study the problem of secrecy wireless information and power transfer in a cognitive relay network (CRN), where a secondary transmitter (ST) aids the signal transmission from a ...primary transmitter to a primary receiver (PR), while it also transmits its own signal to a second receiver (SR). Both the PR and SR decode information and harvest energy from the received signals based on a power splitting strategy. Due to the open architecture of a CRN, the information for SR is prone to be eavesdropped by PR. This letter aims to minimize the transmit power at ST while guaranteeing minimum information rates and the amounts of harvested energy at PR and SR, and constraining the potential eavesdropping rate at PR. Considering imperfect channel state information at ST, we propose a joint robust beamforming and transformation matrix at ST and power splitting at the PR and SR schemes, which can minimize the transmit power in the worst case. Finally, simulation results validate the effectiveness of the proposed scheme.
The effects of cinnamate UV absorbers with different structures on the proliferation of human hepatocellular SMMC-7721 cells were investigated, and the mechanisms of toxicity were analyzed from two ...perspectives: cellular models and molecular models.
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•Cinnamate UV absorbers (CUVAs) induced apoptosis and mitochondrial damage.•Bio-toxicity of CUVAs was investigated by cellular models and molecular models.•The toxicological mechanism of CUVAs was related to mitochondrial apoptosis pathway.•The toxicological mechanism of CUVAs was related to protein conformational changes.•The toxicity of CUVAs to SMMC-7721 cells was related to the branched chain structure.
Organic UV absorbers (UVAs) are contaminants of emerging concern. Environmental persistence and potential toxicological enrichment studies of UVAs have attracted international concern. It is important to study the toxicity mechanism of UVAs. This study is the first to report the toxicological mechanism of two cinnamate UV absorbers (CUVAs), 2-ethyl 4-methoxycinnamate (OMC) and isoamyl 4-methoxycinnamate (IMC) based on cellular models and molecular models. Cellular models demonstrated that the CUVAs-induced apoptosis might be associated with cellular mitochondrial damage pathways. The results of molecular models showed that OMC and IMC could affect the binding between major proteins and enzymes in the mitochondrial damage pathway and contaminants, ultimately leading to apoptosis. The cellular-molecular models showed that IMC and OMC have dose–effect relationships on cytotoxicity. The composite model is more informative than a single model. This study further indicate that UVAs causes toxicology effects that have implications for the environment and human health.
The coronavirus disease 2019 (COVID-19) pandemic poses a current world-wide public health threat. However, little is known about its hallmarks compared to other infectious diseases. Here, we report ...the single-cell transcriptional landscape of longitudinally collected peripheral blood mononuclear cells (PBMCs) in both COVID-19- and influenza A virus (IAV)-infected patients. We observed increase of plasma cells in both COVID-19 and IAV patients and XIAP associated factor 1 (XAF1)-, tumor necrosis factor (TNF)-, and FAS-induced T cell apoptosis in COVID-19 patients. Further analyses revealed distinct signaling pathways activated in COVID-19 (STAT1 and IRF3) versus IAV (STAT3 and NFκB) patients and substantial differences in the expression of key factors. These factors include relatively increase of interleukin (IL)6R and IL6ST expression in COVID-19 patients but similarly increased IL-6 concentrations compared to IAV patients, supporting the clinical observations of increased proinflammatory cytokines in COVID-19 patients. Thus, we provide the landscape of PBMCs and unveil distinct immune response pathways in COVID-19 and IAV patients.
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•We generated a single-cell atlas of PBMCs in both COVID-19 and influenza patients•Plasma cells increase significantly in both COVID-19 and influenza patients•COVID-19 is featured with XAF1-, TNF-, and FAS-induced T cell apoptosis•COVID-19 activates distinct pathway (STAT1/IRF3) versus influenza (STAT3/NFκB)
COVID-19 and influenza are both respiratory infections with cytokine release syndrome. Zhu et al. use single-cell RNA sequencing of longitudinally collected PBMCs in both patients to reveal distinct immune response landscapes of the two diseases and identify virus-specific cell composition and immune response pathways.
Self-blocking modular multilevel converter (SB-MMC) is able to block dc fault current with relatively lower number of power semiconductors and lower valve power loss compared to other dc fault ...tolerant MMC topologies. Operating principle, design, reliability, and redundancy analysis of SB-MMC have been studied while the equivalent modeling and application of SB-MMC at overhead VSC-HVDC have not been fully investigated. Since operating principle of SB-MMC is different from half-bridge MMC, the existing equivalent modeling method of half-bridge MMC cannot be directly applied to modeling of SB-MMC. As dc fault at overhead VSC-HVDC are typically temporary, how to securely and quickly restart a VSC-HVDC after isolating dc fault also needs detailed studies. To solve the above two challenges, an equivalent model (EM) and a fast recovery control of overhead VSC-HVDC based on SB-MMC are proposed. Accuracy of the proposed model is verified by extensive simulations in PSCAD/EMTDC. The proposed fast recovery control further exploits the control capability of SB-MMC and enables fast and secure recovery of overhead VSC-HVDC based on SB-MMC. The proposed model and controllers also provide guidance for the modeling and application of other MMC topologies that are able to block dc fault current.
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