Atomic substitutions at the tetrahedral site (ATd) could theoretically achieve an efficient optimization of the charge at the octahedral site (BOh) through the ATd‐O‐BOh interactions in the spinel ...oxides (AB2O4). Despite substantial progress having been made, the precise control and adjustment of the spinel oxides are still challenging owing to the complexity of their crystal structure. In this work, we demonstrate a simple solvent method to tailor the structures of spinel oxides and use the spinel oxide composites (ACo2O4/NCNTs, A=Mn, Co, Ni, Cu, Zn) for oxygen electrocatalysis. The optimized MnCo2O4/NCNTs exhibit high activity and excellent durability for oxygen reduction/evolution reactions. Remarkably, the rechargeable liquid Zn–air battery equipped with a MnCo2O4/NCNTs cathode affords a specific capacity of 827 mAh gZn−1 with a high power density of 74.63 mW cm−2 and no voltage degradation after 300 cycles at a high charging–discharging rate (5 mA cm−2). The density functional theory (DFT) calculations reveal that the substitution could regulate the ratio of Co3+/Co2+ and thereby lead to the modulation of the electronic structure accompanied with the movement of the d‐band center. The tetrahedral and octahedral sites interact through the Mn−O−Co, and the Co3+Oh of MnCo2O4 with the optimal charge structure allows a more suitable binding interaction between the active center and the oxygenated species, resulting in superior oxygen electrocatalytic performance.
A series of Co‐based spinel oxides coupled with N‐doped carbon nanotubes were synthesized as electrocatalysts for the oxygen reduction/evolution reaction. The cation‐tuning induced ATd‐O‐BOh corner‐sharing effect enables the modulation and optimization of the electronic structure of Co‐based spinel oxides, resulting in the superior electrocatalytic activity.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
With the gradual industrial development of the Fuyu oil formation in the X oilfield and the frequent occurrence of set losses in the stratigraphic parts of the Nengjiang Formation, the importance of ...the overall characterisation of the fracture system has increased significantly. By establishing an integrated model of the fracture system from the Nengjiang Formation to the Quantui Formation, research work such as batch extraction of fracture elements and comparative analysis of the characteristics of the fracture system in the X Oilfield was carried out. The study shows that the Yaojia Formation to Quantou Formation fault system, vertically, has a multi-phase fault inheritance relationship; when the faults formed at a later stage develop, the faults formed at an earlier stage are revived again and grow together with the later faults, and the development pattern of the present-day faults is the result of multiple phases of tectonic movements and the cumulative development of faults.
Improving the sulfur loading in cathodes is a significant challenge for practical lithium–sulfur batteries. Although carbonaceous sulfur hosts can achieve higher sulfur content and loading, the low ...tap densities of carbonaceous materials lead to low volumetric energy densities, restricting practical application. Here, conductive porous laminated vanadium nitride (VN) as a carbon-free sulfur host has been successfully developed to construct high tap density, high sulfur loading, and high energy density sulfur electrodes. The laminated stacking multiscale VN featuring interconnected holes possesses high storage space for sulfur loading, achieving high sulfur loading and utilization. VN@S materials’ sulfur content and tap density can achieve 80 wt % and 1.17 g cm–3, respectively. At the sulfur loading of 1.0 mg cm–2, the VN@S cathode reaches the reversible capacity of 790 mAh g–1 at 1 C after 200 cycles and 145.2 mAh g–1 at 15 C after 500 cycles. Precisely, at a high sulfur loading of 12.6 mg cm–2, the VN@S cathode delivers a reversible capacity of 518.8 mAh g–1 (485.6 mAh cm–3) at 0.1 C after 100 cycles.
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IJS, KILJ, NUK, PNG, UL, UM
Festuca kryloviana is a significant native grass species in the Qinghai Lake region, and its low emergence rate is a primary factor limiting the successful establishment of cultivated grasslands. The ...region's arid and low-rainfall climate characteristics result in reduced soil moisture content at the surface. Despite the recognized impact of water availability on plant growth, the specific role of moisture in seedling development remains not fully elucidated. This study aims to investigate the germination rate and seedling growth velocity of F. kryloviana seeds under varying moisture conditions, and to integrate physiological and transcriptomic analyses of seedlings under these conditions to reveal the mechanisms by which water influences seedling development. The emergence rate of F. kryloviana seedlings exhibited an initial increase followed by a decrease with increasing moisture content. The highest emergence rate, reaching 75%, was observed under 20% soil moisture conditions. By the eighth day of the experiment, the lengths of the plumules and radicles under the optimal emergence rate (full water, FW) were 21.82% and 10.87% longer, respectively, than those under closely matching the soil moisture content during the background survey (stress water, SW). The differential development of seedlings under varying moisture regimes is attributed to sugar metabolism within the seeds and the accumulation of abscisic acid (ABA). At FW conditions, enhanced sugar metabolism, which generates more energy for seedling development, is facilitated by higher activities of alpha-amylase, sucrose synthase, and trehalose-6-phosphate synthase compared to SW conditions. This is reflected at the transcriptomic level with upregulated expression of the alpha-amylase (AMY2) gene and trehalose-6-phosphate synthase (TPS6), while genes associated with ABA signaling and transduction are downregulated. Additionally, under FW conditions, the expression of genes related to the chloroplast thylakoid photosystems, such as photosystem II (PSII) and photosystem I (PSI), is upregulated, enhancing the seedlings' light-capturing ability and photosynthetic efficiency, thereby improving their autotrophic capacity. Furthermore, FW treatment enhances the expression of the non-enzymatic antioxidant system, promoting metabolism within the seeds. In contrast, SW treatment increases the activity of the enzymatic antioxidant system, including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), to cope with water stress. Our experiment systematically evaluated the impact of moisture conditions on the growth and development of F. kryloviana seedlings. Physiological and transcriptomic data collectively indicate that adequate water (20%) supply enhances seedling growth and development by reducing ABA levels and increasing alpha-amylase activity within seeds, thereby boosting sugar metabolism and promoting the growth of seedling, which in turn leads to an improved emergence rate. Considering water management in future cultivation practices may be a crucial strategy for enhancing the successful establishment of F. kryloviana in grassland ecosystems.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
(a) The schematic illustration of ZnSn catalysts growth on Zn foil and (b) the possible reaction pathways for the electrochemical reduction of CO2 to C1 products on the surface of ZnSn catalyst.
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The introduction of tin (Sn) into Zn-based catalyst can change its intrinsic properties of the electrochemically reduction of CO2 to CO, obtaining a high formate yield. The electron transfer from Zn to Sn lowers down the d-band center of Sn, leading to a more reliable surface adsorption of the *OCHO intermediate and high formate selectivity. The obtained ZnSn catalyst enables formate formation with a drastically boosted Faradaic efficiency (FE) up to 94%, which is 2.04 and 1.34 times of pure Zn and Sn foils, respectively, indicating a synergistic effect between Zn and Sn. During the electrochemical CO2 reduction reaction (eCO2RR) process, the morphology of the ZnSn catalyst evolved from nanoparticles to nanosheets, nanoneedles and collapsed structures, corresponding to the activation, stabilization and decay stages, respectively. This study provides a facile and controllable approach for the construction of novel bimetallic catalyst favoring formate selectivity based on the synergistic effect.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Alterations in the composition and function of the gut microbiota have been reported in patients with type 2 diabetes mellitus (T2DM). Emerging studies show that prescribed antidiabetic drugs distort ...the gut microbiota signature associated with T2DM. Even more importantly, accumulated evidence provides support for the notion that gut microbiota, in turn, mediates the efficacy and safety of antidiabetic drugs. In this review, we highlight the current state-of-the-art knowledge on the crosstalk and interactions between gut microbiota and antidiabetic drugs, including metformin, α-glucosidase inhibitors, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter 2 inhibitors, traditional Chinese medicines and other antidiabetic drugs, as well as address corresponding microbial-based therapeutics, aiming to provide novel preventative strategies and personalized therapeutic targets in T2DM.
Constipation is the most common gastrointestinal complaint all over the world, and it is a risk factor of colorectal cancer. In this study, the protective of Quercetin against loperamide‐induced ...constipation and its potential mechanism in a rat model were investigated. Results showed that Quercetin at 25 mg/kg and 50 mg/kg could significantly (p < .05) increase the intestinal transit rate, motilin, gastrin, substance P levels, and concentration of short‐chain fatty acids (SCFAs), reduce the somatostatin levels, and improve the gastrointestinal peristalsis of rats. In addition, the expression levels of enteric nerve‐related factors, glial cell line‐derived neurotrophic factor (GDNF), transient receptor potential vanilloid 1 (TRPV1), nitric oxide synthase (NOS), c‐Kit, stem cell factor (SCF), and aquaporin 3 (AQP3) were examined by RT‐qPCR and/or Western blot analysis. The results suggest that Quercetin relieves loperamide‐induced constipation by increasing the levels of interstitial cells of Cajal markers (c‐Kit and SCF), as well as AQP3. In conclusion, the present study suggested that Quercetin exerted a protective effect against loperamide‐induced constipation, which may be associated with its role in regulation of multiple signal pathways.
Quercetin exerted a protective effect against loperamide‐induced constipation. The possible protective mechanisms of Quercetin might involve the innate immune response via modulating the c‐kit/SCF pathway and other pathways.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Aimed at discovering small molecules as anticancer drugs or lead compounds from plants, a lindenane-type sesquiterpene dimer, chlorahololide D, was isolated from Chloranthus holostegius. The ...literature review showed that there were few reports on the antitumor effects and mechanisms of chlorahololide D. Our biological assay suggested that chlorahololide D blocked the growth and triggered apoptosis of MCF-7 cells by stimulating the reactive oxygen species (ROS) levels and arresting the cell cycle at the G2 stage. Further mechanism exploration suggested that chlorahololide D regulated apoptosis-related proteins Bcl-2 and Bax. Moreover, chlorahololide D inhibited cell migration by regulating the FAK signaling pathway. In the zebrafish xenograft model, chlorahololide D was observed to suppress tumor proliferation and migration significantly. Considering the crucial function of angiogenesis in tumor development, the anti-angiogenesis of chlorahololide D was also investigated. All of the research preliminarily revealed that chlorahololide D could become an anti-breast cancer drug.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Receptor clustering on the cell membrane is critical in the signaling of many immunoreceptors, and this mechanism has previously been attributed to the extracellular and/or the intracellular ...interactions. Here, we report an unexpected finding that for death receptor 5 (DR5), a receptor in the tumor necrosis factor receptor superfamily, the transmembrane helix (TMH) alone in the receptor directly assembles a higher-order structure to drive signaling and that this structure is inhibited by the unliganded ectodomain. Nuclear magnetic resonance structure of the TMH in bicelles shows distinct trimerization and dimerization faces, allowing formation of dimer-trimer interaction networks. Single-TMH mutations that disrupt either trimerization or dimerization abolish ligand-induced receptor activation. Surprisingly, proteolytic removal of the DR5 ectodomain can fully activate downstream signaling in the absence of ligand. Our data suggest a receptor activation mechanism in which binding of ligand or antibodies to overcome the pre-ligand autoinhibition allows TMH clustering and thus signaling.
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•Transmembrane helix of death receptor 5 oligomerizes to drive downstream signaling•The transmembrane helix in lipid bilayer forms dimer-trimer interaction network•Receptor ectodomain in pre-ligand state inhibits receptor clustering and activation•Ligand binding overcomes the pre-ligand autoinhibition
Unlike traditional receptor clustering mediated by intracellular and extracellular domain oligomerization, the transmembrane domain alone of some TNF family receptors can form higher-order structures competent to drive signaling, basally inhibited by the unliganded ectodomain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In science classrooms, technology affordance varies depending on device-student ratios (DSR) and the ways virtual manipulatives on mobile devices are used. Additionally, external scripts (ES) are ...widely used to promote effective group interaction in collaborative learning. Therefore, this research explored the influence of DSR and ES on collaborative inquiry learning. This research adopted a counterbalanced design between two rounds of experiments. A total of 128 students (including 11 dropouts) from four sixth-grade classes participated, with the four classes randomly divided into four experimental groups. Thematic analysis, social network analysis, and statistical analysis methods were used to analyze the distribution and transition of roles, the interaction between roles, and the self-efficacy and collective efficacy of the roles. The results illustrated that the role distribution was affected by DSR and ES, and frequent transitions of operational roles in groups emerged when DSR was exchanged. Moreover, the role of ES was reported in this study; it promoted the stability of role interaction on the one hand while significantly promoting self-efficacy and collective efficacy on the other. The study also proposed that the discourse statuses of different roles in collaborative learning were significantly different, and roles with a weaker discourse status had lower self-efficacy.
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BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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