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Fucosylation is a common glycan terminal modification, which has been reported to be inhibited by 2-fluorofucose (2FF) both in vivo and in vitro. The present study aimed to investigate the effect of 2FF on acetaminophen (APAP)-induced acute liver injury, and further clarified the possible mechanisms. In the present study, inhibition of fucosylation by 2FF relieved APAP-induced acute liver injury in vivo. Pretreatment with 2FF remarkably suppressed APAP-induced oxidative stress and mitochondria damage. 2FF markedly enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and simultaneously promoted the expression of downstream proteins including HO-1 and NQO1. Furthermore, pretreatment with 2FF significantly suppressed the expression of inflammation-associated proteins, such as COX2 and iNOS. The data from lectin blot assay revealed that the alteration of α1,6-fucosylation was involved in APAP-induced acute liver injury. The second part of this study further confirmed that the enhancements to antioxidant capacity of 2FF pretreatment and α1,6-fucose deficiency were related to Nrf2/keap1 and NF-κB signaling pathways in HepG2 cells. Taken together, the current study suggested that 2FF might have a potential therapeutic effect for APAP-induced acute liver injury.

Astragalus residue powder (ARP)/thermoplastic starch (TPS)/poly(lactic acid) (PLA) biocomposites were prepared by fused-deposition modeling (FDM) 3D-printing technology for the first time in this paper, and certain physico-mechanical properties and soil-burial-biodegradation behaviors of the biocomposites were investigated. The results showed that after raising the dosage of ARP, the tensile and flexural strengths, the elongation at break and the thermal stability of the sample decreased, while the tensile and flexural moduli increased; after raising the dosage of TPS, the tensile and flexural strengths, the elongation at break and the thermal stability all decreased. Among all of the samples, sample C—which was composed of 11 wt.% ARP, 10 wt.% TPS and 79 wt.% PLA—was the cheapest and also the most easily degraded in water. The soil-degradation-behavior analysis of sample C showed that, after being buried in soil, the surfaces of the samples became grey at first, then darkened, after which the smooth surfaces became rough and certain components were found to detach from the samples. After soil burial for 180 days, there was weight loss of 21.40%, and the flexural strength and modulus, as well as the storage modulus, reduced from 82.1 MPa, 11,922.16 MPa and 2395.3 MPa to 47.6 MPa, 6653.92 MPa and 1476.5 MPa, respectively. Soil burial had little effect on the glass transition, cold crystallization or melting temperatures, while it reduced the crystallinity of the samples. It is concluded that the FDM 3D-printed ARP/TPS/PLA biocomposites are easy to degrade in soil conditions. This study developed a new kind of thoroughly degradable biocomposite for FDM 3D printing.

Astragalus is widely cultivated in China, and the residue of Astragalus particles (ARP) can be used as reinforcements in fused filament-fabricated (FFF) natural fiber/Poly(lactic acid)(PLA) biocomposites. To clarify the degradation behavior of such biocomposites, 3D-printed 11 wt% ARP/PLA samples were buried in soil, and the effects of soil burial duration on the physical appearance, weight, flexural properties, morphology, thermal stability, melting, and crystallization properties were investigated. At the same time, 3D-printed PLA was chosen as a reference. The results showed that, with prolonged soil burial, the transparency of PLA decreased (but not obviously), while the surface photographs of ARP/PLA became gray with some black spots and crevices; especially after 60 days, the color of the samples became extremely heterogeneous. After soil burial, the weight, flexural strength, and flexural modulus of the printed samples all reduced, and greater losses happened to ARP/PLA pieces than pure PLA. With an increase in soil burial time, the glass transition, cold crystallization, and melting temperatures, as well as the thermal stability of PLA and ARP/PLA samples, all increased gradually. Additionally, soil burial had a greater effect on the thermal properties of ARP/PLA. The results showed that the degradation behavior of ARP/PLA was more significantly affected by soil burial than the behavior of PLA. Additionally, ARP/PLA more easily degraded in soil than PLA.

In order to further explore the feasibility of the application of the residue of Chinese herbal medicine in FDM 3D technology and enrich the kinds of printing materials, Astragalus residue powder(ARP)/poly(lactic acid) (PLA) biocomposite was FDM 3D-printed, meanwhile, two traditional biocomposites, i.e., wood flour (WF)/PLA and rice straw powder (RSP)/PLA, were prepared by the same method, and the properties of the biocomposites were comparatively investigated. The results showed that, the tensile and flexural strengths of ARP/PLA were 28.33 MPa and 97.60 MPa, respectively, which were 2.85% and 10.89% smaller than those of WF/PLA, while 15.73% and 7.04% greater than those of RSP/PLA. WF/PLA showed typical brittle fracture characteristics, ARP/PLA and RSP/PLA both showed ductile fracture, but not obviously. Among the three kinds of biocomposites, ARP/PLA was the most thermally stable, followed by WF/PLA and RSP/PLA in turn. The incorporation of natural plant powder had no significant effect on the glassy transition, melting, and cold-crystallization behaviors of PLA, but the crystallinity of PLA could be increased from 0.3% to 2.0% and 1.9%, respectively, by adding ARP and WF. At 20 °C, the storage modulus of ARP/PLA, WF/PLA and RSP/PLA was 2759.4 MPa, 3361.3 MPa, and 2691.5 MPa, respectively, indicating that WF/PLA has the greatest stiffness, and the stiffness of RSP/PLA was the least. In addition to these, all the biocomposites were hydrophilic, the contact angle of the distilled water on the surface of ARP/PLA, WF/PLA or RSP/PLA was correspondingly 73.5°, 77.6° and 71.2°. Overall, it can be concluded that ARP/PLA has moderate strengths, stiffness and wettability, meanwhile, it is the most thermal stable among the three biocomposites, and can be processed at a temperature close to that of PLA. ARP/PLA is suitable as a new kind of feedstock material for FDM 3D printing.

In order to develop a new kind of filament material for the fused deposition modeling (FDM) 3D printing, the residue of Astragalus (ROA), one of the most important Chinese herbal medicines, and polylactic acid were chosen as the raw materials to FDM 3D print biomass composite specimens, the effects of the printing parameters on the properties of the specimens were investigated. The results indicated that the mechanical properties and thermal stability of the printed specimen were affected obviously by the parameters while the melting and crystallization behavior of the specimens were little affected. For the wettability, it was also little affected by the printing parameter except for the printing speed. Increasing the printing temperature and the filling density or reducing the printing speed and the layer thickness could improve both the mechanical properties and the thermal stability of the FDM 3D printed PLA/ROA composite specimen; reducing the deposition angle could also improve the mechanical properties while having little effect on the thermal stability of the specimen.

The hollow axle is the key component of the high-speed train, and the realization of high-quality forming is the key to ensure the safety of train operation. In this paper, the specimen of the variable-diameter section of the hollow axle is taken as the research object, and the generation mechanism of surface spiral mark defects and the formula of spiral mark depth of variable-diameter section in the TRSR (three-roll skew rolling) process with variable roll spacing are explored. The external roundness error and the function C to measure the wall thickness uniformity of the cross-section were taken as the evaluation indexes and the single-factor simulation experiment was established and simulated in the software Simufact.forming16.0 to obtain the influence law of each process parameter on the external roundness error and wall thickness uniformity of the rolled piece. Orthogonal tests were designed and the order and optimal combination of process parameters on the forming quality were obtained by range analysis and ANOVA analysis. The research results provide theoretical guidance for improving the forming quality of the variable-diameter section of the hollow axle in three-roll skew rolling, and promote the transformation of the TRSR process to high performance and accurate forming.

Fucosylation is one of the most important glycan terminal modifications that affects multiple biological activities of proteins. 2-Fluorofucose (2FF), its specific inhibitor, has recently been reported to reveal numerous biological effects by blocking fucosylation both in vitro and in vivo. The current study aimed to evaluate the effect of 2FF on hydrogen peroxide (H2O2)-induced oxidative damage in vitro. In our study, treatment with H2O2 increased the level of fucosylation, and 2FF improved the cell viability in H2O2-treated HepG2 cells. Our study also showed that 2FF significantly decreased the overproduction of reactive oxygen species (ROS) induced by H2O2 and the activities of catalase, glutathione and Mn-superoxide dismutase were remarkably increased by 2FF pretreatment. Furthermore, 2FF attenuated H2O2-induced early mitochondria dysfunction. The second part of the study revealed that 2FF enhanced antioxidant capacity by affecting Nrf2/keap1 and NF-κB signaling pathways in HepG2 cells. Being pretreated with 2FF significantly increased the nuclear translocation of Nrf2 and simultaneously promoted the expression of downstream proteins, such as HO-1 and NQO1. Moreover, 2FF remarkably suppressed the expression of inflammation-associated proteins. Taken together, these data suggest that 2FF might have a potential therapeutic effect for oxidative stress.

The research aim of this work was to understand the effects of the soil burial of rice straw on the morphology and properties of 3D-printed rice straw powder (RSP)/polylactic acid (PLA) biocomposites. The rice straw buried in the soil for various days was grounded and sieved into powder at 120 mesh. The RSP was then mixed with PLA at a mass ratio of 15/100 and the mixture was extruded into filament, followed by a fused deposition modeling 3D printing process. The as-prepared products were characterized in terms of morphological, mechanical, thermal, and nonisothermal crystallization properties. The results show that cavities with large holes induced by fused deposition modeling exhibit on the cross section of RSP/PLA biocomposite. The longer the burial duration of rice straw, the more the cavities with large holes could be observed on the surface. Therefore, soil burial of rice straw improved the thermal stability of the biocomposites while depressing their mechanical properties due to the amplification of the cavities. The crystallinity of the biocomposites was maintained at a low level (

Apocarotenoids, which play important roles in the growth and development of horticultural plants, are produced by the action of carotenoid cleavage oxygenase (CCO) family members or nonenzymatic cleavage actions. Apocarotenoids are commonly found in leaves, flowers, and fruits of many horticultural plants and participate in the formation of pigments, flavors, hormones, and signaling compounds. Some of them are recognized as important aroma components of fruit and flower with aromatic odor, such as βß-ionone, β-damascenone, and 6-methyl-5-hepten-2-one in tomato fruit, and have low odor thresholds with β-ionone having odor threshold of only 0.007 ppb. In this review, the main apocarotenoid aroma components in horticultural plants were listed, and factors influencing their production were discussed at first. Then, the biosynthetic pathway of apocarotenoid aromas was briefly introduced, and the CCDs gene family was highlighted, and the nonenzymatic production of apocarotenoid aromas was also mentioned. Next, chemical and molecular regulations of apocarotenoid aromas and their biological activities were summarized. Finally, further exploration aspects needed were suggested. We anticipate that this review can afford some crucial information for comprehensive application of apocarotenoid volatile compounds in horticultural plants.

To improve the production quality and efficiency of the concave ring, a multi-pass stamping technology is used to replace the spinning technology to form the concave ring. First, the multi-pass stamping dies are designed according to the structural characteristics of the concave ring. Then, the process parameters are determined based on the bending conditions and the dimensional requirements of the concave ring. Next, the rationality of the designed stamping dies is verified by analyzing the stress and strain field of the multi-pass stamping concave ring. Finally, the stamping experiments are carried out. Experimental results show that the dimensional error of the concave ring formed by multi-pass stamping is less than 0.5%. The multi-pass stamping technology is feasible to form the concave ring. The reasonable design of the mold is the key factor to prevent defects in the workpiece. The concave ring formed by multi-pass stamping meets the industrial requirements.

To reveal growth properties of Chlorella sorokiniana UTEX 1230, four monosaccharides (glucose, fructose, galactose and xylose) were individually supplemented into medium as carbon sources for the cultivation of C. sorokiniana UTEX 1230. Supplementation with glucose increased OD750, biomass and lipid yield but decreased protein abundance per unit dry weight of biomass under all concentrations examined, the maximum OD750, biomass and lipid yield increased 2.04, 6.78 and 12.43 times, respectively, compared with autotrophic controls. A low concentration of glucose (

Reference proteins and biomarkers are important for the quantitative evaluation of protein abundance. Chlamydomonas reinhardtii was grown under five stress conditions (dark, cold, heat, salt, and glucose supplementation), and the OD750 and total protein contents were evaluated on days 0, 1, 2, 4, and 6 of culture. Antibodies for 20 candidate proteins were generated, and the protein expression patterns were examined by western blotting. Reference protein(s) for each treatment were identified by calculating the Pearson’s correlation coefficient (PCC) between target protein abundance and total protein content. Histone H3, beta tubulin 1 (TUB-1), ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (RBCL), and mitochondrial F1F0 ATP synthase subunit 6 (ATPs-6) were the top reference proteins, because they were expressed stably under multiple stress conditions. The average relative-fold change (ARF) value of each protein was calculated to identify biomarkers. Heat shock protein 90B (HSP90B), flagellar associated protein (FAP127) and ATP synthase CF0 A subunit (ATPs-A) were suitable biomarkers for multiple treatments, while receptor of activated protein kinase C1 (RCK1), biotin carboxylase (BCR1), mitochondrial phosphate carrier protein (MPC1), and rubisco large subunit N-methyltransferase (RMT1) were suitable biomarkers for the dark, cold, heat, and glucose treatments, respectively.

In order to improve the competitiveness of wind power in participating in the power market, promote low-carbon operation of the power system, and meet the new requirements for the completeness and flexibility of the production simulation model due to the uncertainty of wind power output,this paper analyzes the electricity cost composition from the perspective of low-carbon economy, and applies the stochastic programming theory to propose a short-term production simulation model of power system containing wind power. Considering the participation of the carbon trading market, this model aims to minimize the expected cost of electricity production in a short-term time scale, and coordinately optimize the day-ahead power output, real-time power regulation, power reserve capacity, wind curtailment, and load shedding. Taking the modified IEEE 39-bus system as an example, this paper quantitatively evaluates the impact of carbon trading mechanism, carbon trading price, and wind power installed capacity on electricity costs and their contributions to carbon emission reduction. The simulation results show that the proposed model can effectively analyze the short-term electricity cost, carbon emissions, and operational risks of the power system containing wind power under the carbon trading environment, thus has a promise application prospect.