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Bicyclol is a synthetic drug for hepatoprotection in clinic since 2004. Preliminary clinical observations suggest that bicyclol might be active against hepatitis C virus (HCV) with unknown mechanism. Here, we showed that bicyclol significantly inhibited HCV replication in vitro and in hepatitis C patients. Using bicyclol as a probe, we identified glycolipid transfer protein (GLTP) to be a novel restrictive factor for HCV replication. The GLTP preferentially bound host vesicle-associated membrane protein-associated protein-A (VAP-A) in competition with the HCV NS5A, causing an interruption of the complex formation between VAP-A and HCV NS5A. As the formation of VAP-A/NS5A complex is essential for viral RNA replication, up-regulation of GLTP by bicyclol reduced the level of VAP-A/NS5A complex and thus inhibited HCV replication. Bicyclol also exhibited an inhibition on HCV variants resistant to direct-acting antiviral agents (DAAs) with an efficacy identical to that on wild type HCV. In combination with bicyclol, DAAs inhibited HCV replication in a synergistic fashion. GLTP appears to be a newly discovered host restrictive factor for HCV replication, Up-regulation of GLTP causes spontaneous restriction of HCV replication. KEY WORDS: Bicyclol, Hepatitis C virus, Glycolipid transfer protein, Host restrictive factor, Protein interaction

Improving our understanding of the patterns and drivers of regional carbon budgets is critical to mitigating climate change regionally and globally. Different from previous research, our study attempts to reveal the comprehensive impact of climate change and human activities factors on the carbon budget. Based on the Carnegie–Ames–Stanford approach (CASA) model, the IPCC inventory method, the ordinary least squares (OLS) regression model, the Geodetector model, and the geographically weighted regression (GWR) method, we investigated the spatiotemporal patterns of the carbon budget in the Yangtze River Delta (YRD) region from 2000 to 2015 and analyzed the effects of climate change and human activities on the carbon budget. The results showed that the carbon budget in the YRD region changed from 271.33 million tons in 2000 to −1193.76 million tons in 2015. During this period, the changes in the carbon budget per unit area in the four provinces all showed a decreasing trend, among which Shanghai decreased the most, followed by Jiangsu, Zhejiang and Anhui. In terms of spatial pattern, the carbon budget of the YRD region has a “core-edge” structural feature. The closer it is to Shanghai, the core area, the more severe the carbon budget deficit; the farther from it, the greater the carbon budget surplus. Overall, we found that human activities have a greater impact on the carbon budget than climate change. The top three drivers were, in order, changes in population density, GDP per capita, and unused land, with q values of 0.3317, 0.1202, and 0.0998, respectively. Locally, the impact of the drivers on the carbon budget shows obvious spatial heterogeneity. In particular, the population density was negatively correlated with carbon budget changes in the entire study area, and the coefficients of GDP per capita and unused land were negative in most counties. Based on the results, we put forward suggestions for restricting population flow among the core area and the peripheral area, promoting industrial innovation in the core area and ecological protection in the peripheral area, as well as implementing three-dimensional space development in the core area and controlling the expansion of construction land in the peripheral area. Our study can provide a scientific basis for low-carbon development in the YRD region. The methodology and findings of this study can provide references for similar studies in other urbanized regions around the world.

“Diversity-enhanced extracts” is an effective method of producing chemical libraries for the purpose of drug discovery. Three rare new cytochalasan derivative chaetoglobosins B1-B3 (1–3) were obtained from chemically engineered crude broth extracts of Chaetomium madrasense 375 prepared by reacting with hydrazine monohydrate and four known metabolite chaetoglobosins (4–7) were also identified from the fungus. The structures were identified by NMR and MS analysis and electronic circular dichroism simulation. In addition, the antiproliferative activities of these compounds were also evaluated, and the drug-resistant activities of cytochalasans were evaluated for the first time. Compound 6 possessed potent activity against four human cancer cells (A549, HCC827, SW620, and MDA-MB-231), and two drug-resistant HCC827 cells (Gefitinib-resistant, Osimertinib-resistant) compared with the positive controls.

Objective: To investigate the associations between short-term exposure to fine particular matter (PM2.5) and ischemic stroke (IS) in Yancheng, China, from 2017 to 2019. Methods: We designed a time-series study based on generalized additive models to explore the association of PM2.5 and IS admitted in two major hospitals in Yancheng. We built different lag patterns and conducted stratification analyses by age, gender, and season. Moreover, we examined the robustness of the associations adopting two-pollutant models and fitted the concentration-response curves. Result: We observed positive and significant associations at lag 0 day. Every 10 μg/m3 increase in PM2.5 (lag0) was associated with 1.06% (95% CI: 0.21%–1.91%) increases in hospitalizations for IS. The association remained stable and statistically significant to the adjustment of carbon monoxide and ozone. We observed that the associations were stronger in females and during cold seasons. The overall concentration-response relationship curve was linear positive and increased slowly but rose sharply at higher concentrations in the cold season. Conclusion: Our study added to the evidence that short-term exposure to PM2.5 may induce IS, and the government should take action to address the air pollution issues and protect susceptible populations.

In order to utilize the low-concentration gas directly discharged into the atmosphere from 1.1% to 1.50% in coal mine production, the heat storage and oxidation equipment of gas was improved, and the heat storage and safety of gas under high-temperature environment were tested. The experimental results show that the regenerative oxidation system could provide a high-temperature oxidation environment of 1000°C for gas oxidation after changing the heating mode and enhancing the sealing property. The pressure curves of air and gas in the burner were similar. With the increase of gas concentration, the pressure difference between inlet and outlet tended to increase linearly with a minimum pressure differential of 4 kPa (air) and a maximum pressure differential of 11 kPa (1.50% gas). The internal pressure was relatively stable without an instantaneous pressure surge or explosion. The result of this study provides a reference for further research on the low-concentration gas regeneration oxidation unit at high temperatures.

Multivariate time series prediction is a very important task, which plays a huge role in climate, economy, and other fields. We usually use an Attention-based Encoder-Decoder network to deal with multivariate time series prediction because the attention mechanism makes it easier for the model to focus on the really important attributes. However, the Encoder-Decoder network has the problem that the longer the length of the sequence is, the worse the prediction accuracy is, which means that the Encoder-Decoder network cannot process long series and therefore cannot obtain detailed historical information. In this paper, we propose a dual-window deep neural network (DWNet) to predict time series. The dual-window mechanism allows the model to mine multigranularity dependencies of time series, such as local information obtained from a short sequence and global information obtained from a long sequence. Our model outperforms nine baseline methods in four different datasets.

The mining area is the main place for the development and utilization of Coalbed Methane (CBM), and there are a series of systems for the development and utilization of CBM. However, owing to lack of a clear understanding of demand-side gas consumption rules and a reasonable resource allocation system, a large amount of CBM resources in the mining area are wasted. In order to predict the demand for CBM dynamically, the Seasonal Auto Regressive Integrated Moving Average (SARIMA) model, Additive Holt-Winters (AHW) model and Multiplicative Holt-Winters (MHW) model based on time series are used to predict the monthly demand for CBM in Yangquan Mine Area in 2020, respectively. Then the predicted results are evaluated by using the prediction model parameters combined with the characteristics of actual demand for CBM. Finally, a resource allocation system under different supply and demand conditions is built to reduce the waste of resources. In this paper, it is found that the information of the actual data is not sufficiently extracted in the MHW model while the SARIMA model can reflect the cyclical trend of monthly demand for CBM under ideal conditions. Furthermore, the AHW model can reasonably predict the demand for CBM under the influence of COVID-19, with a mean relative error of 0.099. The supply and demand distribution system built based on the proposed models can solve the problem of seasonal unevenness of CBM demand in mining areas and ensure the economic benefits of mining areas.

l-theanine, a non-protein-derived amino acid, is widely used as a functional ingredient in foods. Here, we evaluated the in vivo effects of l-theanine on glutamine metabolism in healthy rats and in a stressed rat model, which was established by infecting rats with enterotoxigenic Escherichia coli (E44813). The results showed that l-theanine significantly enhanced the synthesis of glutamine and stabilized the intestinal tract in healthy rats. In E44813-stressed rats, l-theanine could replace l-glutamine, thereby alleviating intestinal stress by reducing the expression of inflammatory factors, enhancing the activities of antioxidant enzymes, and regulating glutamine metabolism by modulating its synthesis. Treatment with a combination of l-theanine and l-glutamine was superior to treatment with l-glutamine alone in enhancing the activity of antioxidant enzymes, reducing the expression of inflammatory factors, and increasing the intestinal villi height and crypt depth.

This paper analyzes the harmonics and vibration under different fault-tolerant current control when one-phase winding of dual three-phase permanent magnet synchronous motor (PMSM) is an open circuit fault. Firstly, the dual three-phase load condition subdomain model of breadloaf surface-mounted permanent magnet (PM) PMSM is established. Secondly, the working conditions of an open circuit fault of one-phase winding are set from the perspectives of no fault-tolerant (NFT) control, maximum torque (MT) control, minimum copper loss (MCL) control and single three-phase mode (STPM) control. The torque harmonics and electromagnetic force harmonics of the four working conditions are analyzed. Then, considering the multi-physical field of electromagnetic and structural coupling, the electromagnetic force in the motor air gap acts on the stator core, and the vibration under four different working conditions is calculated and analyzed. Through the comparison between the analytical method and finite element method, the accuracy of the established model is verified. The calculation method is effective and accurate, it can quickly predict the motor performance in case of one-phase open circuit fault of dual three-phase PMSM.

The performances of data transmissions in vehicular network are investigated. In the vehicular network, the data transmissions are realized by the proposed transmission strategies. Under a cognitive way, the specific strategy is adopted in the corresponding transmission duration. In this paper, the vehicle-to-pedestrian, vehicle-to-vehicle, and vehicle-to-infrastructure/network transmission modes are adopted to implement the data transmission. In the data transmission durations, the transmission modes transit among one another based on the strategies decisions. A state transition model is proposed to describe the communication and evaluate the performances. The concept of effective capacity is adopted, and the mathematical expression of effective capacity is derived. Besides, the effective capacity under the parameter constraints is also demonstrated. From the specific simulations, it is shown that the effective capacity is the most sensitive to quality-of-service exponent. The pedestrian density and vehicle density also impose significant impact on the transmission performances. Besides, short transmission range of the infrastructures and vehicles is necessary to improve the effective capacity.

Tea [Camellia sinensis (L.)] plants are important economic crop in China. Chilling stress and freezing damages have seriously affected the quality of tea products that have been already regarded as the main restricting factors to industry’s development. Nitric oxide (NO) plays a crucial role in resistance of abiotic stresses. An experiment was conducted in an artificial climate chamber to study the effect of NO on tea plants grown under chilling stress (−2 °C) for 0, 6, 24, 48, and 72 h. Foliar application of sodium nitroprusside (SNP) at a rate of 500 μmol·L−1 was used as NO donor. The experiment contained two factors: the first was the foliar application with SNP or distilled water, and the scond one was the chilling (−2 °C) exposure time (0, 6, 24, 48, and 72 h). The effects of NO on membrane lipid peroxidation, osmotic adjustment substances, and antioxidant activity under cold stress were studied. In addition, the gene expression of CsICE1 and CsCBF1 in respond to NO addition were also investigated using real-time polymerase chain reaction (RT-PCR). The results show that foliar addition of NO (500 μmol·L−1 of SNP) reduce the relative conductivity of tea leaves, inhibits the elevated malondialdehyde content, promotes the accumulation of proline, soluble protein and sugar, and increases the superoxide dismutase, catalase activities, thereby alleviates the damage of cold stress on tea leaves. The CsICE1 expression in 500 μM SNP treatment was peaked at 24 h of low temperature stress, while it did not express at normal temperature. Therefore, the current study is considered a good scientific material in understanding how tea plants sense and defense the chilling stress and that plays an important role to improve the level of production and economic benefits. It is also provided significant theory bas to control chilling stress in tea plants.

Abstract Kalanchoe daigremontiana reproduces asexually by producing plantlets along the leaf margin. The aim of this study was to identify the function of the SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 gene in Kalanchoe daigremontiana (KdSOC1) during plantlet morphogenesis. In this study, KdSOC1 gene expression was detected at stem cell niche during in vitro somatic embryogenesis and plantlet morphogenesis. Disrupting endogenous auxin transportation suppressed the KdSOC1 gene response. Knockdown of the KdSOC1 gene caused a defect in cotyledon formation during the early heart stage of somatic embryogenesis. Over-expression (OE) of the KdSOC1 gene resulted in asymmetric plantlet distribution, a reduced number of plantlets, thicker leaves, and thicker vascular fibers. Higher KdPIN1 gene expression and auxin content were found in OE plant compared to those of wild-type plant leaves, which indicated possible KdSOC1 gene role in affecting auxin distribution and accumulation. KdSOC1 gene OE in DR5-GUS Arabidopsis reporting lines resulted in an abnormal auxin response pattern during different stages of somatic embryogenesis. In summary, the KdSOC1 gene OE might alter auxin distribution and accumulation along leaf margin to initiate plantlet formation and distribution, which is crucial for plasticity during plantlet formation under various environmental conditions.

With mining technology and mechanization degree being improving, fully mechanized caving mining technology (FCM) has become a main method for thick coal seam extraction in China. However, roof-coal caving characteristics in turn restrict its recovery efficiency, especially for the coal seam with complicated structure (CCS), that is, the coal seam comprises hard or soft coal and gangue. In order to explore the key factors influencing the roof-coal caving and recovery characteristics, related research work has been conducted as follows: firstly, a mechanical model of CCS has been established, which indicates the strength of the coal and gangue will directly affect the roof-coal recovery. Meanwhile, based on the geological settings of Qinyuan coal mine, numerical simulation on roof-coal caving law under different thicknesses of hard or soft coal and gangue has been performed using UDEC software. The results show that the maximum principal stress will increase with the increase of mining depth, making the roof-coal to break easily. Furthermore, the range of the plastic zone of the top coal and the damage degree of the top coal increase with the increase of mining depth. Physical modeling results show that when an extraction-caving ratio is 1, the number of times the coal arch forms is 0.43 at every caving, up to a maximum of 3; the number of times coal arch forms with an extraction-caving ratio of 2 is 4.65 times larger than that with an extraction-caving ratio of 1. The probability of coal arch formation with an extraction-caving ratio of 3 is minimal, about 0.4, which is due to that the arch span is large and the curvature is small, so it is difficult to form a stable arch structure. According to the mechanical characteristics of roof-coal in Qinyuan coal mine, deep-hole blasting technique has been used to reduce the fragments of roof-coal crushed. The results show that this technique can effectively improve the recovery of roof-coal.

A chelating fabric was prepared by graft polymerization of glycidyl methacrylate (GMA) onto a nonwoven fabric, followed by attachment reaction of N-methyl-D-glucamine (NMDG) using an organic solvent-free process. The graft polymerization was performed by immersing the gamma-ray pre-irradiated fabric into the GMA emulsion, while the attachment reaction was carried out by immersing the grafted fabric in the NMDG aqueous solution. The chelating capacity of the chelating fabric prepared by reaction in the NMDG aqueous solution without any additives reached 1.74 mmol/g, which further increased to above 2.0 mmol/g when surfactant and acid catalyst were added in the solution. The boron chelation of the chelating fabric was evaluated in a batch mode. Fourier transform infrared spectrophotometer (FTIR) was used to characterize the fabrics. The chelating fabric can quickly chelate boron from water to form a boron ester, and a high boron chelating ability close to 18.3 mg/g was achieved in the concentrated boron solution. The chelated boron can be eluted completely by HCl solution. The regeneration and stability of the chelating fabric were tested by 10 cycles of the chelation-elution operations. Considering the organic solvent-free preparation process and the high boron chelating performance, the chelating fabric is promising for the boron removal from water.

A nonwoven fabric adsorbent loaded with 2-ethylhexyl hydrogen-2-ethylhexylphosphonate (EHEP) was developed for the separation and recovery of dysprosium (Dy) and neodymium (Nd) from an aqueous solution. The adsorbent was prepared by the radiation-induced graft polymerization of a methacrylate monomer with a long alkyl chain onto a nonwoven fabric and the subsequent loading of EHEP by hydrophobic interaction and chain entanglement between the alkyl chains. The adsorbent was evaluated by batch and column tests with a Dy (III) and Nd (III) aqueous solution. In the batch tests, the adsorbent showed high Dy (III) adsorptivity close to 25.0 mg/g but low Nd (III) adsorptivity below 1.0 mg/g, indicating that the adsorbent had high selective adsorption. In particular, the octadecyl methacrylate (OMA)-adsorbent showed adsorption stability in repeated tests. In the column tests, the OMA-adsorbent was also stable and showed high Dy (III) adsorptivity and high selectivity in repeated adsorption–elution circle tests. This result suggested that the OMA-adsorbent may be a promising adsorbent for the separation and recovery of Dy (III) and Nd (III) ions.

To determine the molecular weight of graft chains in grafted films, the polystyrene graft chains of PVDF−g−St films synthesized by a pre-irradiation graft method are cleaved and separated by boiling xylene extraction. The analysis of the extracted material and the residual films by FTIR, nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) analyses indicates that most graft chains are removed from the PVDF−g−St films within 72 h of extraction time. Furthermore, the molecular weight of the residual films decreases quickly within 8 h of extraction and then remains virtually unchanged up to 72 h after extraction time. The degradation is due to the cleavage of graft bonds, which is mainly driven by the thermal degradation and the swelling of graft chains in solution. This allows determination of the molecular weight of graft chains by GPC analysis of the extracted material. The results indicate that the PVDF−g−St prepared in this study has the structure where one or two graft chains hang from each PVDF backbone.

The inductive reaction sphere (RS) brings the benefit of simple, economical, and miniaturized design, and it is capable of multi-DOF torque generation. Thus, it is a suitable choice for the angular momentum exchange actuator in attitude control of micro-spacecrafts. To synthesize symmetric distribution of eddy currents and improve the speed and stability of rotation, a novel 4-pole winding design is proposed. However, the developed simplified analytical model shows that reduced pole number degrades the torque generation. To enhance the output torque of 4-pole RS, its curved cores and electromagnets are redesigned to enable the side teeth to be functional. As the analytical torque model for the RS with the slotted cores is not available, a constrained optimization problem is formulated, and the optimized parameters are calculated based on the prediction model from supported vector machine and finite element analysis. The lab prototypes are developed to validate the proposed design and test the speed performance. The experimental results show that the 4-pole RS prototype obtains a stable rotation over 700 rpm about X, Y and Z axis respectively with the angular momentum of 0.08 kg·m 2 /s, being superior to the 6-pole counterpart.

To remove chromium from wastewater effectively, two types of nitrogen-containing fabric adsorbents, having amidoxime ligand groups and quaternary ammonium anion exchange groups, respectively, were prepared by radiation grafting. In brief, the amidoxime adsorbent is obtained by grafting of acrylonitrile (AN)/methacrylic acid (MAA) onto a nonwoven fabric and subsequent amidoximation with hydroxylamine, while the ammonium adsorbent is obtained by grafting of chloromethylstyrene (CMS) followed by quaternization with trimethylamine. The AN/MAA-grafting reaches a high degree of grafting more than 100%, and the resulting amidoxime adsorbent reaches a high amidoxime density of 4.53 mmol/g. On the other hand, the CMS-grafting reaches a much higher degree of grafting above 200%, and the resulting ammonium adsorbent reaches a high ammonium density of 3.51 mmol/g. FTIR/ATR and TGA/DTA are used for the characterization of the grafted fabrics as well as the relevant fabric adsorbents. Furthermore, the chromium removal of the prepared fabric adsorbent is tested in both batch and column modes. It has been confirmed that the chromium removal was largely dependent on the pH of the solution. At pH 5.0, the amidoxime adsorbent shows a high Cr(III) adsorption capacity of 31.68 mg/g, while the ammonium adsorbent shows a much higher Cr(VI) adsorption capacity of 130.65 mg/g.

Reversible addition-fragmentation chain transfer (RAFT) agent was added into a simultaneous radiation grafting system and its effects on graft polymerization and homopolymerization were investigated. Chloromethylstyrene (CMS) was graft polymerized onto ethylene-tetrafluoroethylene copolymer (ETFE) films under γ-ray sources via simultaneous irradiation. The non-grafted poly(CMS) in the grafted films were extracted by xylene at 120 °C. The poly(CMS) was characterized by NMR and GPC instruments. Addition of the RAFT agent suppressed both graft polymerization and homopolymerization. However, under a high concentration of RAFT agent, the homopolymerization in the monomer solution could occur through a typical RAFT polymerization while polymerization in the ETFE films proceeded via RAFT and conventional radical polymerization, resulting in poly(CMS) in the ETFE films with molecular weight dispersity higher than 1.0 but lower than that without RAFT agent. Furthermore, it was found that the molecular weight of the poly(CMS) in the ETFE films was several times higher than that of the poly(CMS) in the monomer solution.

Free-piston linear generators (FPLGs) have attractive application prospects for hybrid electric vehicles (HEVs) owing to their high-efficiency, low-emissions and multi-fuel flexibility. In order to achieve long-term stable operation, the hybrid system design and full-cycle operation strategy are essential factors that should be considered. A 25 kW FPLG consisting of an internal combustion engine (ICE), a linear electric machine (LEM) and a gas spring (GS) is designed. To improve the power density and generating efficiency, the LEM is assembled with two modular flat-type double-sided PM LEM units, which sandwich a common moving-magnet plate supported by a middle keel beam and bilateral slide guide rails to enhance the stiffness of the moving plate. For the convenience of operation processes analysis, the coupling hybrid system is modeled mathematically and a full cycle simulation model is established. Top-level systemic control strategies including the starting, stable operating, fault recovering and stopping strategies are analyzed and discussed. The analysis results validate that the system can run stably and robustly with the proposed full cycle operation strategy. The effective electric output power can reach 26.36 kW with an overall system efficiency of 36.32%.

This paper proposes a decoupling design approach for a free-piston linear generator (FPLG) constituted of three key components, including a combustion chamber, a linear generator and a gas spring serving as rebounding device. The approach is based on the distribution of the system power and efficiency, which provides a theoretical design method from the viewpoint of the overall power and efficiency demands. The energy flow and conversion processes of the FPLG are analyzed, and the power and efficiency demands of the thermal-mechanical and mechanical-electrical energy conversion are confirmed. The energy and efficiency distributions of the expansion and compression strokes within a single stable operation cycle are analyzed and determined. Detailed design methodologies of crucial geometric dimensions and operational parameters of each key component are described. The feasibility of the proposed decoupling design approach is validated through several design examples with different output power.

In the title compound, [Ce(C9H4N2O4)(C2H3O2)(H2O)]n, the CeIII ion is coordinated by five O atoms and one N atom from four 1H-benzimidazole-5,6-dicarboxylato (L) ligands and by two O atoms from an acetate ligand and one aqua ligand, forming a slightly distorted tricapped trigonal–prismatic geometry. The L ligands are bridging, forming a layered polymer parallel to (010). In the crystal, O—H...O and N—H...O hydrogen bonds connect the polymer layers into a three-dimensional network.

The crystal structure of the two-dimensional polymeric title compound, [Pb(C9H4N2O4)]n, comprises one crystallographically independent PbII atom and one fully deprotonated 1H-benzimidazole-5,6-dicarboxylate (H2L) ligand. The PbII atom is seven-coordinated by six O atoms and one N atom from the H2L ligands, giving a capped octahedral coordination geometry. The structure is a layered two-dimensional coordination polymer extending parallel to (100) with N—H...O hydrogen bonds interactions between the layers, stabilizing the crystal structure.