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As the most common sleep disorder, insomnia seriously affects people's everyday lives. Phytochemicals have been shown to have excellent sleep-promoting effects. Therefore, this study was designed to investigate whether Rg5 and Rk1 extracted from ginseng had sleep-promoting effects and to explore their potential mechanisms. The results showed that Rg5 and Rk1 could significantly lessen the locomotor activity of mice and promote the sleep quality index, including increasing the amount of sleep in a pentobarbital sodium experiment with a threshold dose. In parallel, Rg5 and Rk1 could significantly shorten the sleep latency of mice and prolong the sleep time of mice. Furthermore, Rg5 and Rk1 augmented the GABA/Glu ratio, up-regulating the expression of the GABAA receptor and the GABAB receptor, whereas the GABAA receptor antagonist picrotoxin could antagonize the sleep quality of Rg5/Rk1. In addition, 5-HTP, the precursor of 5-HT, could enhance the sleep effect of Rg5 and Rk1 in mice, and both Rg5 and Rk1 could up-regulate the expression of 5-HT1A. These results were also confirmed by the detection of GABA and 5-HT in mouse cecum content. In conclusion, ginsenoside Rg5/Rk1 can exert sedative and hypnotic effects by affecting the GABA nervous system and the serotonin nervous system.

Exploring high efficient and cost-effective electrocatalysts for oxygen evolution reaction is a determination step towards sustainable green energy applications. Polyoxometalates and layered double hydroxide materials are suggested to be potential catalyst materials; however, those electrocatalytic behaviors are greatly inferior to the state-of-the-art OER electrocatalysts (RuO2 and IrO2). In this work, we employ a self-assembly approach in which polyoxometalate anions are successfully intercalated into NiFe layered double hydroxide. Upon analysis of the composition, the elemental valence state and the infrared spectrum, it confirms that the intercalated polyoxometalate anions in the layers of NiFe layered double hydroxide are in the format of PW12O403−. Even though the partial anions in the as-prepared intercalation NiFe layered double hydroxide are only polyoxometalate anions, its electrochemical performance surpasses the counterpart precursor NiFe layered double hydroxide (NO3−) in many aspects, such as turnover frequencies, overpotentials, kinetics, and stability. The introduction of polyoxometalate anions can optimize the local electronic structure which enhances the charge transport capacity of NiFe layered double hydroxide as well as alter the adsorption/desorption nature of the intermediates during the catalysis process. This work provides a new strategy to boost the OER activity of layered double hydroxide-based electrocatalysts.

Defect engineering has been used to develop low-cost and effective catalysts to boost oxygen reduction reactions. However, the development of catalysts that use metal cation vacancies as the active sites for oxygen reduction reaction is lacking. In this study, ZnS nanoparticles on N-doped carbon serve as an oxygen reduction reaction catalyst. These catalysts were prepared via a one-step method at 900 °C. Amazingly, the high-resolution transmission electron microscope image revealed obvious defects in the ZnS nanoparticles. These facilitated the catalyst synthesis, and the product displayed good electrocatalytic performance for the oxygen reduction reaction in an alkaline medium, including a lower onset potential, lower mid-wave potential, four electron transfer process, and better durability compared with 20 wt% Pt/C. More importantly, the density functional theory results indicated that using the Zn vacancies in the prepared catalyst as active sites required a lower reaction energy to produce OOH* from *OO toward oxygen reduction reaction. Therefore, the proposed catalyst with Zn vacancies can be used as a potential electrocatalyst and may be substitutes for Pt-based catalysts in fuel cells, given the novel catalyst's resulting performance.

Acetylene chemical process, especially catalyzing acetylene acetoxylation for the synthesis of vinyl acetate (VAc), has attracted wide attention in coal-rich countries. Although great efforts have been made to prepare different catalysts to improve the VAc synthesis via acetylene acetoxylation, the acetic acid (HAc) conversion cannot achieve a satisfactory level, much lower than 60%. Herein, ZnO nanoparticles in situ wrapped on zinc-nitrogen-carbon materials (ZnO@ Zn–N–C) have been successfully synthesized. Due to the simultaneous presence of nitrogen and carbon in chitosan, the obtained carbon material achieved in situ nitrogen doping during the high-temperature treatment. Furthermore, the as-obtained ZnO@Zn–N–C exhibits high specific surface area of 1430.1 m2/g and pore volume of 0.92 cm3/g, because Zn composites have the ability to etch carbon to form pores. In particular, ZnO@Zn–N–C displays an amazing catalytic activity for acetylene acetoxylation to synthesize VAc with the HAc conversion high up to 88.8%, which is much higher than those reported in other papers before.

Fe-based carbon materials are widely considered promising to replace Pt/C as next-generation electrocatalysts towards oxygen reduction reaction (ORR). However, the preparation of Fe-based carbon materials is still carried out by conventional heating method (CHM). Herein, a novel microwave-assisted carbon bath method (MW-CBM) was proposed, which only took 35 min to synthesize Fe/Fe3C nanoparticles encapsulated in N-doped carbon layers derived from Prussian blue (PB). The catalyst contained large specific surface area and mesoporous structure, abundant Fe-Nx and CN active sites, unique core-shell structure. Due to the synergistic effects of these features, the as-prepared Fe/Fe3C@NC-2 displayed outstanding ORR activity with onset potential of 0.98 VRHE and half-wave potential of 0.87 VRHE, which were more positive than 20 wt.% Pt/C (0.93 VRHE and 0.82 VRHE). Besides, Fe/Fe3C@NC-2 gave a better stability and methanol tolerance than Pt/C towards ORR in alkaline media, too. Keywords: Fe/Fe3C nanoparticles, Prussian blue, Microwave, Carbon bath method, Oxygen reduction reaction

High active and durable non-noble metal electrocatalysts are urgently developed to satisfy the high performance oxygen reduction reaction (ORR). We successfully synthesized Co-CoOx anchored on nitrogen-doped carbon via a facile sand-bath method (SBM), i.e., Co-CoOx/N-C (SBM). The as-obtained Co-CoOx/N-C (SBM) exhibited overwhelming superiorities to Co-CoO/N-C prepared by conventional heat treatment (CHT), particularly in electrochemical performance of ORR. Although Co-CoOx/N-C (SBM) showed smaller specific surface area of 276.8 m2/g than that of 939.5 m2/g from Co-CoO/N-C (CHT), the Co-CoOx/N-C (SBM) performed larger pore diameter and more Co3O4 active component resulting in better ORR performance in 0.1 mol/L KOH solution. The Co-CoOx/N-C (SBM) delivered onset potential of 0.91 V vs. RHE, mid-wave potential of 0.85 V vs. RHE and limited current density of 5.46 mA/cm2 much better than those of the Co-CoO/N-C (CHT). Furthermore, Co-CoOx/N-C (SBM) showed greater stability and better methanol tolerance superior to the commercial 20 wt% Pt/C.

BackgroundAbscisic acid (ABA) plays an important role in plant growth and adaptation through the ABA signaling pathway. The ABA-responsive element binding (AREB/ABF) family transcriptional factors are central regulators that integrate ABA signaling with various signaling pathways. It has long been known that ABA inhibits rhizobial infection and nodule formation in legumes, but the underlying molecular mechanisms remain elusive.ResultsHere, we show that nodulation is very sensitive to ABA and exogenous ABA dramatically inhibits rhizobial infection and nodule formation in soybean. In addition, we proved that GmbZIP1, an AREB/ABF transcription factor, is a major regulator in both nodulation and plant response to ABA in soybean.GmbZIP1was specifically expressed during nodule formation and development. Overexpression ofGmbZIP1resulted in reduced rhizobial infection and decreased nodule number. Furthermore,GmbZIP1is responsive to ABA, and ectopic overexpression ofGmbZIP1increased sensitivity of Arabidopsis plants to ABA during seed germination and postgerminative growth, and conferred enhanced drought tolerance of plants. Remarkably, we found that GmbZIP1 directly binds to the promoter ofGmENOD40–1, a marker gene for nodule formation, to repress its expression.ConclusionOur results identified GmbZIP1 as a node regulator that integrates ABA signaling with nodulation signaling to negatively regulate nodule formation.

Cartilage tissue engineering has become the trend of cartilage defect repair owing to the engineered biomimetic tissue that can mimic the structural, biological and functional characteristics of natural cartilage. Biomaterials with high biocompatibility and regeneration capacity are expected to be used in cartilage tissue engineering. Herein, in this study, a dual-network bovine serum albumin/sodium alginate with hydroxyapatite nanowires composite (B-S-H) hydrogel scaffold has been prepared for cartilage repair. The obtained B-S-H hydrogel scaffold exhibits ideal physical properties, such as excellent mechanical strength, high porosity and swelling ratio, as well as the excellent biological activity to promote the human bone marrow derived mesenchymal stem cells (hBMSCs) proliferation and differentiation. The in vivo study further shows that the B-S -H hydrogel scaffold can obviously promote the generation of new cartilage that integrates well with surrounding tissues and is similar to adjacent cartilage in terms of thickness. It is considered that the B-S-H hydrogel scaffold has great potential in the application of cartilage defects repair.

The aim of this study is to explore the effect of flavonoids from Rosa roxburghii Tratt (FRRT) on doxorubicin (DOX)-induced autophagy of myocardial cells. Primary isolation and culture of myocardial cells and H9C2 myocardial cell lines from 1 to 3-day-old rats were performed, myocardial cells were incubated using 5 μmol/L DOX and a cardiotoxicity model was established, intervention was conducted via FRRT, and the ultrastructure of myocardial cells was observed under a transmission electron microscope. The expressions of LC3-II and P62 proteins were detected through immunofluorescence and Western blotting. The ultrastructure showed a large quantity of autophagic vacuoles of the cells in DOX group with poor cell state. After the FRRT intervention, only a small quantity of autophagic vacuoles appeared in the myocardial cells, and there were many coarse microvilli on the cell surface. The expression of P62 protein was reduced in DOX group, while that in FRRT group was increased (p

Electrocatalysts with strong stability and high electrocatalytic activity have received increasing interest for oxygen reduction reactions (ORRs) in the cathodes of energy storage and conversion devices, such as fuel cells and metal-air batteries. However, there are still several bottleneck problems concerning stability, efficiency, and cost, which prevent the development of ORR catalysts. Herein, we prepared bimetal FeCo alloy nanoparticles wrapped in Nitrogen (N)-doped graphitic carbon, using Co-Fe Prussian blue analogs (Co3[Fe(CN)6]2, Co-Fe PBA) by the microwave-assisted carbon bath method (MW-CBM) as a precursor, followed by dielectric barrier discharge (DBD) plasma treatment. This novel preparation strategy not only possessed a fast synthesis rate by MW-CBM, but also caused an increase in defect sites by DBD plasma treatment. It is believed that the co-existence of Fe/Co-N sites, rich active sites, core-shell structure, and FeCo alloys could jointly enhance the catalytic activity of ORRs. The obtained catalyst exhibited a positive half-wave potential of 0.88 V vs. reversible hydrogen electrode (RHE) and an onset potential of 0.95 V vs. RHE for ORRs. The catalyst showed a higher selectivity and long-term stability than Pt/C towards ORR in alkaline media.

Half-Heusler compounds usually exhibit relatively higher lattice thermal conductivity that is undesirable for thermoelectric applications. Here we demonstrate by first-principles calculations and Boltzmann transport theory that the BiBaK system is an exception, which has rather low thermal conductivity as evidenced by very small phonon group velocity and relaxation time. Detailed analysis indicates that the heavy Bi and Ba atoms form a cage-like structure, inside which the light K atom rattles with larger atomic displacement parameters. In combination with its good electronic transport properties, the BiBaK shows a maximum n-type ZT value of 1.9 at 900 K, which outperforms most half-Heusler thermoelectric materials.