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31.
Graphite anodes are well established for commercial use in lithium-ion battery systems. However, the limited capacity of graphite limits the further development of lithium-ion batteries. Hard carbon obtained from biomass is a highly promising anode material, with the advantage of enriched microcrystalline structure characteristics for better lithium storage. Tannin, a secondary product of metabolism during plant growth, has a rich source on earth. But the mechanism of hard carbon obtained from its derivation in lithium-ion batteries has been little studied. This paper successfully applied the hard carbon obtained from tannin as anode and illustrated the relationship between its structure and lithium storage performance. Meanwhile, to further enhance the performance, graphene oxide is skillfully compounded. The contact with the electrolyte and the charge transfer capability are effectively enhanced, then the capacity of PVP-HC is 255.5 mAh g−1 after 200 cycles at a current density of 400 mA g−1, with a capacity retention rate of 91.25%. The present work lays the foundation and opens up ideas for the application of biomass-derived hard carbon in lithium anodes.  相似文献   
32.
In this study, Scenedesmus sp. FSP3 was cultured using a two-stage culture strategy for CO2 fixation and lutein production. During the first stage, propylene carbonate was added to the medium, with 5% CO2 introduced to promote the rapid growth and CO2 fixation of the microalgae. During the second stage of cultivation, a NaCl concentration of 156 mmol L−1 and a light intensity of 160 μmol m−2 s−1 were used to stimulate the accumulation of lutein in the microalgal cells. By using this culture method, high lutein production and CO2 fixation were simultaneously achieved. The biomass productivity and carbon fixation rate of Scenedesmus sp. FSP3 reached 0.58 g L−1 d−1 and 1.09 g L−1 d−1, with a lutein content and yield as high as 6.45 mg g−1 and 2.30 mg L−1 d−1, respectively. The results reveal a commercially feasible way to integrate microalgal lutein production with CO2 fixation processes.  相似文献   
33.
Indigenous Saccharomyces cerevisiae, as a new and useful tool, can be used in fermentation to enhance the aroma characteristic qualities of the wine-production region. In this study, we used indigenous S. cerevisiae L59 and commercial S. cerevisiae FX10 to ferment Prince (a new hybrid variety from Lion Winery) wine, detected the basic physicochemical parameters and the dynamic changes of fungal communities during fermentation, and analyzed the correlations between fungal communities and volatile compounds. The results showed that the indigenous S. cerevisiae L59 could quickly adapt to the specific physicochemical conditions and microbial ecology of the grape must, showing a strong potential for winemaking. Compared with commercial S. cerevisiae FX10, the wine fermented by indigenous S. cerevisiae L59 contained more glycerol and less organic acids, contributing to a rounder taste. The results of volatile compounds indicated that the indigenous S. cerevisiae L59 had a positive effect on adding rosy, honey, pineapple and other sweet aroma characteristics to the wine. Overall, the study we performed showed that selection of indigenous S. cerevisiae from the wine-producing region as a starter for wine fermentation is conducive to improving the aroma profile of wine and preserving the aroma of the grape variety.  相似文献   
34.
Vanadomolybdates (VMos), comprised of Mo and V in high valences with O bridges, are one of the most important types of polyoxometalates (POMs), which have high activity due to their strong capabilities of gaining/losing electrons. Compared with other POMs, the preparation of VMos is difficult due to their relatively low structural stability, especially those with unclassical architectures. To overcome this shortcoming, in this study, triol ligands were applied to synthesize VMos through a beaker reaction in the presence of V2O5, Na2MoO4, and organic species in the aqueous solution. The single-crystal X-ray diffraction results indicate that two VMo clusters, Na4{V5Mo2O19[CH3C(CH2O)3]}∙13H2O and Na4{V5Mo2O19[CH3CH2C(CH2O)3]}∙13H2O, with a similar architecture, were synthesized, which were both stabilized by triol ligand and {MoO6} polyhedron. Both clusters are composed of five V ions and one Mo ion in a classical Lindqvist arrangement with an additional Mo ion, showing an unprecedented hepta-nuclear VMo structure. The counter Na+ cations assemble into one-dimensional channels, which facilitates the transport of protons and was further confirmed by proton conductivity experiments. The present results provide a new strategy to prepare and stabilize VMos, which is applicable for developing other compounds, especially those with untraditional architectures.  相似文献   
35.
The tumor-suppressor gene, WW domain-containing oxidoreductase (WWOX), has been found to be lost in various types of cancers. ROS result as a tightly regulated signaling process for the induction of cell senescence. The aim of this study was to investigate the role of WWOX in the regulation of ROS and cell senescence, which is intriguing in terms of the possible mechanism of WWOX contributing to bladder cancer. In this study, we used the AY-27 rat bladder tumor cell line and F344 orthotopic bladder tumor models to reveal the pro-senescence effects of WWOX and the corresponding underlying mechanism in bladder cancer. WWOX-overexpressing lentivirus (LV-WWOX) remarkably stimulated cellular senescence, including increased senescence-associated secretory phenotype (SASP) formation, enlarged cellular morphology, and induced SA-β-Gal-positive staining. A further mechanism study revealed that the pro-senescence effect of LV-WWOX was dependent on increased intercellular reactive oxygen species (ROS) generation, which subsequently triggered p21/p27. Moreover, LV-WWOX significantly inhibited the tumor size by 30.49% in the F344/AY-27 rat orthotopic model (p < 0.05) by activating cellular senescence. The expression of p21 was significantly enhanced in the orthotopic bladder tumors under WWOX treatment. The orthotopic bladder tumors in the groups of rats verified the effect in vivo. Our study suggests that WWOX, an ROS-dependent senescence-induced gene, could be further studied for its therapeutic implications in bladder cancer.  相似文献   
36.
Pickled radish (Raphanus sativus) is a traditional Asian ingredient, but the traditional method takes decades to make this product. To optimize such a process, this study compared the saponin content of pickled radishes with different thermal processing and traditional processes (production time of 7 days, 10 years, and 20 years) and evaluated the effects of different thermal processes on the formation of radish saponin through kinetics study and mass spectrometry. The results showed that increasing the pickling time enhanced the formation of saponin in commercial pickled radishes (25 °C, 7 days, 6.50 ± 1.46 mg g−1; 3650 days, 23.11 ± 1.22 mg g−1), but these increases were lower than those induced by thermal processing (70 °C 30 days 24.24 ± 1.01 mg g−1). However, it was found that the pickling time of more than 10 years and the processing temperature of more than 80 °C reduce the saponin content. Liquid chromatography–mass spectrometry (LC-MS) analysis showed that the major saponin in untreated radish was Tupistroside G, whereas treated samples contained Asparagoside A and Timosaponin A1. Moreover, this study elucidated the chemical structure of saponins in TPR. The findings indicated that thermal treatment could induce functional saponin conversion in plants, and such a mechanism can also be used to improve the health efficacy of plant-based crops.  相似文献   
37.
Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease with limited therapeutic options. Pseudognaphalium affine (D. Don) Anderb. is a medicinal and edible plant used to treat cough, asthma, and COPD for a long time in folk medicine. The objective of this study is to evaluate the effect of Pseudognaphalium affine (D. Don) Anderb. extract (GAE) and investigate the possible underlying mechanism in vivo and in vitro. In vivo, the administration of GAE in a rat COPD model could significantly ameliorate lung damage and pulmonary function by inhibiting the production of pro-inflammatory cytokines. Western blot and real-time PCR results showed that GAE could suppress nuclear translocation of nuclear factor-kappa B (NF-κB), which indicated that GAE down-regulated the NF-κB pathway. Moreover, GAE protected against tumor necrosis factor (TNF)-α induced inflammatory response in BEAS-2B and inhibited the NF-κB pathway. All data suggested that GAE exhibited its anti-COPD effect by inhibiting pro-inflammatory cytokines, which may be associated with the inhibition of the NF-κB pathway.  相似文献   
38.
Allergic inflammation is a T helper 2 (Th2) cell-driven pathophysiological phenomenon, but the mechanism by which the metabolic cascade affects Th2 cell differentiation remains unclear. In this study, we investigated the roles of AMP-activated protein kinase (AMPK) and intracellular energy sensors in Th2 cell differentiation and the pathogenesis of allergic inflammation. Accordingly, T-cell-specific AMPK or Sirtuin 1 (Sirt1)-knockout mice were subjected to allergic inflammation, and their Th2 cell responses were investigated. The results demonstrated that inducing allergic inflammation in AMPK- and Sirt1-knockout mice increased Th2 cell responses and exacerbated allergic phenotypes. Furthermore, treatment with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), an activator of AMPK, ameliorated allergic inflammation in mice. Mechanistically, our findings revealed that AMPK repressed mechanistic target of rapamycin complex 2 (mTORC2), which downregulated the expression of suppressor of cytokine signaling 5 (SOCS5) in CD4+ T cells. In addition, the loss of AMPK signaling reduced SOCS5 expression and increased interleukin-4-STAT6–GATA3 axis-mediated Th2 cell differentiation. Finally, the T-cell-specific deletion of Rictor, a member of mTORC2, in Sirt1T-KO mice led to the reversal of allergic exacerbation to the level in control mice. Overall, our findings suggest that AMPK in CD4+ T cells inhibits the differentiation of Th2 cells by repressing mTORC2 and thus serves as a potential target for Th2 cell-associated diseases.Subject terms: Lymphocytes, Inflammation  相似文献   
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