The main purpose of the current study was to investigate the ameliorative effects of bovine milk osteopontin (bmOPN) on the gut dysfunction of pregnant rats fed a high-fat diet (HFD). Bovine milk ...osteopontin was supplemented at a dose of 6 mg/kg body weight. Bovine milk osteopontin supplementation during pregnancy reduced colonic inflammation of HFD dams, and it also increased the colonic expression of ZO-1 and claudin-4 of HFD dams. Bovine milk osteopontin significantly enriched the relative abundance of Bacteroidetes, whereas it decreased Proteobacteria, Helicobacteraceae, and Desulfovibrionaceae in feces of HFD dams. The levels of isobutyric acid and pentanoic acid in the HFD + bmOPN group were higher than that of the HFD group. Functional predication analysis of microbial genomes revealed that bmOPN supplementation to HFD pregnancies changed 4 Kyoto Encyclopedia of Genes and Genomes pathways including bile acid biosynthesis. Further, bmOPN enriched hepatic taurochenodeoxycholic acid and tauroursodeoxycholic acid plus taurohyodeoxycholic acid in the gut of HFD maternal rats. Our findings suggested that bmOPN improved the gut health of HFD pregnant rats partially through modulating bile acid biosynthesis.
Nitrogen-doped graphitic carbon materials have been extensively studied as potential replacements for Pt-based electrocatalysts for the oxygen reduction reaction (ORR). However, little is known about ...the catalytic mechanisms, including the parameters that determine the selectivity of the reaction. By comparing theoretical calculations of the ORR selectivity at a well-defined graphene nanostructure with experimental results, we propose a model based on interfacial solvation to explain the observed preference for the four-electron pathway in alkaline electrolytes. The hydrophobic environment around the active sites, as in enzymatic catalysis, restricts the access of water and destabilizes small ionic species such as peroxide, the product of the two-electron pathway. This model, when applied to acidic electrolytes, shows the ORR preferring the two-electron pathway, consistent with the well-known pH-dependent ORR selectivity catalyzed by graphitic carbon materials. Because of the similarity between more complex N-doped graphitic carbon materials and our model system, we can extend this model to the former and rationalize nearly all of the previously reported experimental results on the selectivity of ORR catalyzed by these materials.
Fold-and-thrust belts are important locations for oil and gas exploration, but due to the complex sources, migration, and charging histories the exploration risk is extremely high. The Longmenshan ...belt in the NW Sichuan Basin offers an excellent opportunity to study the genesis and sources of natural gas in fold-and-thrust belt. We synthesize existing geochemical data from ∼1100 samples from various strata in the Sichuan Basin. Among them, the bitumen biomarkers and the natural gas molecular compositions and stable carbon isotopes in the Middle Permian of different structural belts were analyzed to investigate the gas genetic types and sources. Then, they were compared with natural gas from other strata in the Sichuan Basin. Results indicate that the Middle Permian natural gases in the NW Sichuan Basin are dominated by hydrocarbon gases, with a small amount of CO2 and N2. The identification of the gas origin and gas-source correlation indicate that there are significant differences between the Middle Permian natural gas in different structural belts of the Longmenshan belt. The natural gas in the thrust nappe belt is mainly oil-cracking gas from the Qiongzhusi Formation (Fm) source rock, and the natural gas in the thrust front belt shows obvious mixed-source characteristics, with both kerogen-cracking gas of the Permian source rocks and oil-cracking gas from the Qiongzhusi Fm source rock. However, the natural gas in the unfaulted belt mainly comes from the kerogen-cracking gas in the Permian source rocks. Overall, from the thrust nappe belt to the thrust front belt, and then to a belt that is largely unfaulted, the contribution of deep source rocks controlled by fault migration channels decreases with gradually weakening deformation. This study will help to better understand the petroleum system in the fold-and-thrust belt and optimize the future exploration strategy.
•The Middle Permian natural gas in the NW Sichuan Basin are typical dry gas.•Oil cracking gas from deep source rock exists in the Middle Permian.•Genesis and sources of natural gas in each structural belt are distinct.•The results are helpful to understand the petroleum system in fold-and-thrust belt.
The seismic vulnerability of interaction system of saturated soft soil and subway station structures was explored in this paper. The coupled nonlinear numerical models of interaction system were ...established using the u-p formulation of Biot's theory to describe the saturated two-phase media. A refined finite element model of interaction system was developed to study its nonlinear seismic responses and seismic hazard mechanism. In this study, the multi-yield elastoplastic constitutive model was adopted for the soil, while a fiber section elastoplastic constitutive model was used for the structure. The seismic response of the structure was calculated by inputting the artificial seismic wave obtained from the power spectrum-triangular series method. The maximum inter-story drift angle was taken as a structural performance parameter for the subway station structure. The structural demand cloud was obtained under random ground motion sequences. Based on the probabilistic seismic demand model analysis method, the seismic vulnerability curve of the subway station structure was plotted, and the seismic vulnerability curve was analyzed as per the vulnerability of performance parameters. With the increase of soil strength, the vulnerability index of subway station structure under different peak acceleration ground motion decreased correspondingly. Based on the above vulnerability theory and analysis methods, it can be found from the above vulnerability theory and analysis methods that the subway station structure with established buried depth in saturated soft soil site exhibits a certain degree of safety and reliability, and can meet the seismic fortification goal of "no damage in small earthquakes, repairable in medium earthquakes and no collapse in large earthquakes". The results of vulnerability analysis are in line with the actual seismic survey, and the vulnerability analysis method proposed in this paper can be applied to the vulnerability analysis of underground structures on saturated soft soil foundation.
The cytochrome P450 family 19 subfamily A member 1 (CYP19A1) gene, encodes aromatase, a key enzyme in estradiol (E2) synthesis, and is down-regulated during porcine follicular atresia. However, its ...role in and the mechanism of transcriptional repression in follicular atresia is largely unknown. In the present study, we show that the CYP19A1 gene stimulates E2 release and inhibits cell apoptosis in porcine granulosa cells (GCs). SMAD4, an anti-apoptotic moderator, was identified as a transcription factor of the porcine CYP19A1 gene and enhanced the expression and function of CYP19A1 in porcine GCs through direct binding to a SMAD4-binding element (SBE) within the promoter region of CYP19A1 gene. Moreover, we found that miR-10b, a pro-apoptotic factor, directly interacted with 3′-UTR of the porcine CYP19A1 mRNA, inhibiting its expression and function in porcine GCs. Collectively, we demonstrated that CYP19A1 is an inhibitor of follicular atresia and is regulated by both SMAD4 and miR-10b. These findings provide further insight into the mechanisms of CYP19A1 in steroid hormone synthesis and GC apoptosis and provide molecular targets for exploring methods of treatment for steroid-dependent reproductive disorders.
•CYP19A1 suppresses porcine GCs apoptosis through controlling E2 release.•SMAD4 promotes CYP19A1 transcription by directly binding to its promoter.•SMAD4-CYP19A1 axis enhances E2 synthesis and prevents porcine GC apoptosis.•miR-10b impairs CYP19A1 expression and functions by targeting its 3′-UTR region.
Single-ended resonant converters such as Class-E inverters have been widely considered as a potential topology for small- and medium-power wireless power transfer (WPT) applications, which feature ...compact circuits, low switching losses, and cost benefits, as they only use a low-side switch with a simple gate driver. However, there remains a practical challenge in the design of voltage stress, efficiency, and power density. In this paper, a single-ended resonant converter with a primary parallel resonant-matching network is investigated to absorb the bulky input-choke inductors of the Class-E inverters into the coil inductance. The analytical expressions for all the converter parameters are derived based on time-domain resonant waveforms, including: (1) analysis of critical zero-voltage switching (ZVS) conditions and (2) power transfer capabilities under the given maximum switch voltage stress. Furthermore, this paper elaborates on the design methodology of the proposed single-ended resonant converters, and an optimal operating point is chosen to ensure soft-switching operation and rated power. Finally, the accuracy of the proposed model is verified by simulation and experimental results.
Improving energy efficiency of electrocatalytic and photocatalytic CO2 conversion to useful chemicals poses a significant scientific challenge. We report on using a colloidal nanographene to form a ...molecular complex with a metal ion to tackle this challenge. In this work, a well-defined nanographene–Re complex was synthesized, in which electron delocalization over the nanographene and the metal ion significantly decreases the electrical potential needed to drive the chemical reduction. We show the complex can selectively electrocatalyze CO2 reduction to CO in tetrahydrofuran at −0.48 V vs NHE, the least negative potential reported for a molecular catalyst. In addition, the complex can absorb a significant spectrum of visible light to photocatalyze the chemical transformation without the need for a photosensitizer.
Metal particles supported by carbon materials are important for various technologies yet not well understood. Here, we report on the use of well-defined colloidal graphene quantum dots as a model ...system for the carbon materials to study metal–carbon interaction. In the case of palladium, our studies show high affinity between the metal nanoparticles with the graphene. IR spectroscopy reveals covalent nature of the interaction between the two, which had been predicted by theoretical calculations yet never directly proven before.
Insulin-stimulated hepatic glycogen synthesis is central to glucose homeostasis. Here, we show that PPP1R3G, a regulatory subunit of protein phosphatase 1 (PP1), is directly phosphorylated by AKT. ...PPP1R3G phosphorylation fluctuates with fasting-refeeding cycle and is required for insulin-stimulated dephosphorylation, i.e., activation of glycogen synthase (GS) in hepatocytes. In this study, we demonstrate that knockdown of PPP1R3G significantly inhibits insulin response. The introduction of wild-type PPP1R3G, and not phosphorylation-defective mutants, increases hepatic glycogen deposition, blood glucose clearance, and insulin sensitivity in vivo. Mechanistically, phosphorylated PPP1R3G displays increased binding for, and promotes dephosphorylation of, phospho-GS. Furthermore, PPP1R3B, another regulatory subunit of PP1, binds to the dephosphorylated GS, thereby relaying insulin stimulation to hepatic glycogen deposition. Importantly, this PP1-mediated signaling cascade is independent of GSK3. Therefore, we reveal a regulatory axis consisting of insulin/AKT/PPP1R3G/PPP1R3B that operates in parallel to the GSK3-dependent pathway, controlling glycogen synthesis and glucose homeostasis in insulin signaling.
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•PPP1R3G is directly phosphorylated by AKT in response to insulin or feeding•PPP1R3G phosphorylation accelerates postprandial glycogenesis and glucose clearance•Phosphorylation of PPP1R3G enhances its association with p-GS•PPP1R3B acts downstream of PPP1R3G to relay insulin signals for glycogen synthesis
Compelling evidence suggests that a GSK3-independent pathway exists, linking insulin signaling with glycogen synthesis. However, the molecular mechanism underlying this pathway remains unclear. Li et al. reveal the presence of an axis for insulin signaling consisting of insulin/AKT/PPP1R3G/PPP1R3B that controls glycogen synthesis and glucose homeostasis in parallel to the GSK3-dependent pathway.
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