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Based on a brief introduction of the spatial distribution, rock types and formation ages of the late Mesoarchean–early Neoarchean (2.6~3.0 Ga) rocks in some key areas of the North China Craton, this paper summarizes the ages and geochemical and Nd-Hf-O isotopic compositions of the granitoids all over the craton. The late Mesoarchean–early Neoarchean basement shows the following features: (1) The late Mesoarchean–early Neoarchean magmatism is almost continuous, with a peak period of 2.70~2.75 Ga; (2) The late Mesoarchean–early Neoarchean rocks widely occur in the North China Craton, mainly in the Eastern Ancient Terrane, the Central Ancient Terrane and the Southern Ancient Terrane; (3) The intrusive rocks are mainly tonalite in composition, with trondhjemite, granodiorite, K-rich granite and gabbro-diorite; (4) The supracrustal rocks are commonly small in scale and scatter in granitoids. The rock types are mainly meta-basaltic rocks. In some areas, there are meta-komatiites, meta-andesitic-dacitic rocks and meta-clastic sedimentary rocks; (5) 2.6 Ga can be regarded as the boundary between the early and late Neoarchean in the North China Craton; (6) TTG rocks show large Sr/Y and La/Yb variations, plotting in the high-, medium- and low-pressure TTG areas in the Sr/Y–Y and La/Yb–Yb diagrams. Except for a few K-rich granites, the late Mesoarchean–early Neoarchean rocks are commonly depleted in Nd-Hf isotope compositions, with the magmatic zircon being similar in O isotope composition to that of the Archean magmatic zircon worldwide; (7) Many regions have similar geological characteristics, but some regions show great uniqueness. The research futher supports the understanding that, similar to many other typical cratons worldwide, the late Mesoarchean–early Neoarchean is the most important period of continental accretion in the North China Craton, and the main difference is that the North China Craton underwent a strong and widespread magmato-tectonothermal event at the end of the Neoarchean.

Studies have shown that antidiabetic drugs can alter the gut microbiota. The hypoglycemic effects of the drugs can be attributed in part to certain species in the gut microbiome that help the drugs work more effectively. In addition, increasing energy expenditure via the induction of adipose tissue browning has become an appealing strategy to treat obesity and associated metabolic complications. Currently, glucagon‐like peptide‐1 receptor agonist (GLP‐1 RA) treatment for metabolic disorders such as obesity and type 2 diabetes has been widely studied. To determine the mechanism of a long‐acting GLP‐1 RA affects adipose tissue browning and the gut microbiome, we treated high‐fat diet mice with GLP‐1 RA and demonstrated that the drug can regulate adipose tissue browning. 16S rRNA and untargeted metabolomics assays suggested that it increased the abundance of bacterium Lactobacillus reuteri and decreased serum ceramide levels in mice. L. reuteri was negatively correlated with ceramide. We found that the mechanism of ceramide decline was alkaline ceramidase 2 (Acer2) overexpression. Moreover, L. reuteri can play a therapeutic synergistic role with GLP‐1 RA, suggesting that gut microbiota can be used as a part of the treatment of diabetes. [ABSTRACT FROM AUTHOR]

In this paper, we study the magnitude of the effective prestressing force of steel strands in prestressed reinforced concrete structures. Through the theory of micro-hole release, the functional relationship equation between tensile stress and strain-containing coefficients A and B is established. Then, Midas FEA NX 2022 (v1.1) finite element software is used to establish the stress-release model of strand drilling holes and analyze the influence of parameters such as drilling depth, drilling diameter, hole–edge distance, and tension stress on the amount of stress release. Finally, through a homemade tensioning platform, we verify the reasonableness of the finite element simulation calculation law and determine coefficients A and B. The results of the study show that based on Kirsch's analytical formula and the theory of microvia release, the axial tension force and axial strain are linearly correlated; the Midas FEA NX finite element software can effectively simulate the force state of strand cross-section; and through the strand-drilled hole model simulation and analysis, it is found that the tension stress value and the stress-release amount are related to the tensile stress value and the tensile stress value. We found that the value of tensile stress and the amount of stress released are positively correlated; with the increase in the hole margin, the amount of stress released gradually decreases; with the increase in the diameter of the hole, the amount of strain released gradually increases; and the greater the depth of the hole, the greater the amount of strain release. Moreover, the use of a hole margin of 3–6 mm, a hole diameter of 1.5 mm and 1.8 mm, and a hole depth of 2.5 mm is more reasonable in the test conditions, as follows. Through the drilling test conditions of 1.5 mm drilling diameter, 2.5 mm drilling depth, and 4 mm hole side distance, we verified the measured strain value of the steel wire and the tensile force value of the linear correlation between the functional relationship and the use of this functional relationship to determine the theoretical derivation of the coefficient to be determined: A is 1.12 and B is 57.84. [ABSTRACT FROM AUTHOR]

Background & Aims: In liver cancer, leucine‐rich repeat‐containing G‐protein coupled receptor 5 (LGR5) compartment represents an important tumor‐initiating cell (TIC) population and served as a potential therapeutic target. Cancer‐associated fibroblasts (CAFs) is a critical part of the tumor microenvironment, heavily influenced TIC function and fate. However, deeply investigations have been hindered by the lack of accurate preclinical models to investigate the interaction between CAFs and TIC. Organoids model have achieved major advancements as a precious research model for recapitulating the morphological aspects of organs, and thus also serving as a candidate model to investigate the mutual interaction between different cell types. Consequently, this study aimed to construct a three‐dimensional (3D) co‐culture organoid model of primary LGR5‐expressing tumor stem cells from primary murine liver tumors with CAFs to investigate the impact of CAFs on LGR5 marked TICs in liver cancer. Materials and Methods: First, both of the transgenic LGR5‐diphtheria toxin receptor (DTR)‐GFP knock‐in mice and transgenic Rosa26‐mT mice developed primary liver tumors by diethylnitrosamine (DEN) administration. Tumor organoids and CAFs were generated from those primary liver cancer separately. Second, LGR5‐expressing TICs organoid with CAFs were established ex vivo based on cell–cell contact or trans‐well co‐culture system, and the mutual influence between those two types of cells was further investigated. Subsequently, immunodeficient mouse‐based xenograft model was further adopted to evaluate the influence of CAFs to LGR5 tumor stem cell, tumor formation, and metastasis. Results: The co‐culture organoid model composed of murine liver tumor LGR5+ tumor‐initiating cells and CAFs in 3D co‐culture was successfully established, with the intention to investigate their mutual interaction. The existence of CAFs upon engrafting tumor organoids resulted in dramatic higher number of LGR5+ cells in the neoplasia when compared with engrafting tumor organoids alone. Furthermore, ex vivo culture of isolated LGR5+ cells from tumors of co‐engrafted mice formed significantly larger size of organoids than mono‐engrafted. Our results also indicated significantly larger size and number of formed organoids, when LGR5+ cells co‐cultured with CAF in both cell–cell contact and paracrine signaling in vitro, comparing to LGR5+ cells alone. Furthermore, we found that specific knockout of LGR5 expressing cells suppressed CAF‐mediated promotion of tumor formation, growth, and metastasis in the experimental mice model. Conclusions: Altogether, in a 3D co‐culture type of murine liver LGR5+ cells and cancer‐associated fibroblasts, we have demonstrated robust effects of CAFs in the promotion of LGR5 marked liver TICs. We also further revealed the influence of tumor microenvironment on stem cell‐related therapy, suggesting the possibility of combing CAF‐targeted and tumor stem cell targeted therapy in treating liver cancer. [ABSTRACT FROM AUTHOR]

In this study, we examined how perceived overqualification influences employees' career distress and career planning. Specifically, we drew on role identity theory to hypothesize that perceived overqualification is positively related to individuals' career identity. Based on internal self‐processing dynamics of role identity, we further hypothesized that career identity predicts reduced career distress and increased career planning. We expected career identity to mediate the effects of overqualification on career distress and career planning. Based on the symbolic interactionism perspective of identity, we hypothesized that this mediation is moderated by leader humility so that overqualified employees exhibit stronger career identities in the presence of a humble leader. We found support for our hypotheses in a multi‐wave time‐lagged study of 220 supervisor–subordinate dyads from 50 groups. Overall, our studies highlight that perceived overqualification can have positive effects on employees and organizations under appropriate management conditions. We discuss theoretical and practical implications of these results. [ABSTRACT FROM AUTHOR]

Copper oxides species deposited on ceria rods, particles, and cubes were examined for low-temperature oxidation of CO. It was found that the shape of ceria altered the dispersion and chemical state of copper species considerably. CuOx monolayers and bilayers were formed on ceria rods and particles, while multilayers and faceted particles co-existed on ceria cubes. The formation of Cu+ species at the copper–ceria interface involved a significant charge transfer from copper oxides to the ceria surface via a strong electronic interaction, which was more pronounced on ceria rods. The concentrations of surface Cu+ and oxygen vacancies followed the order rods > particles > cubes, in line with their catalytic activity for CO oxidation at 343 K. [ABSTRACT FROM AUTHOR]

The clinical efficacy of personalized cancer vaccines still needs to be improved due to their insufficient immune effect. The development of innovative adjuvants and lymph node‐targeted delivery systems is the key to improving the clinical efficacy of personalized vaccines. However, there is still a lack of an adjuvant delivery system that is simple in preparation and capable of mass production and integrates adjuvant and lymph node targeted delivery functions. Here, this work reports that a simple dendrimer polypeptide (KK2DP7) nanoparticle enhances the immune efficacy of an OVA/neoantigen‐based vaccine. Due to its multiple functions as a delivery vehicle, immune adjuvant, and facilitator of dendritic cell migration, KK2DP7 efficiently increases the efficiency of antigen uptake and cross‐presentation by antigen‐presenting cells (APCs) and delivers antigens to lymph nodes via APCs. Strikingly, the antitumor effect of KK2DP7/OVA is superior to that of commonly used adjuvants such as poly(I:C), CpG, and aluminum adjuvant combined with OVA. Furthermore, KK2DP7/OVA combined with anti‐PD‐1 antibody is able to prevent tumor recurrence in a postoperative recurrent tumor model. Thus, KK2DP7‐based cancer vaccines alone or in combination with immune checkpoint blockade therapies to treat tumors or postoperative tumor recurrence are a powerful strategy to enhance antitumor immunity. [ABSTRACT FROM AUTHOR]

Human bone marrow-derived mesenchymal stem cells (hBMSCs) are promising candidates for stem cell therapy in clinical trials. Applications of hBMSCs in clinical therapy are limited by cellular senescence due to long-term ex vivo expansion. Metformin, an oral hypoglycemic drug for type 2 diabetes, has been shown to have antiaging effects. However, the mechanisms of metformin in antiaging treatment remain controversial. Here, we used D-galactose (D-gal) to establish an appropriate model of senescent hBMSCs to explore the antiaging effects of metformin. Following metformin treatment with a low concentration range, senescence phenotypes induced by D-gal significantly changed, including generation of reactive oxygen species (ROS), loss of mitochondrial membrane potential (MMP), and cell cycle arrest. In contrast, no apparent change was found in unsenescent hBMSCs. Furthermore, the results show that activation of 5 ′ AMP-activated protein kinase (AMPK) by metformin enhances cell autophagy in senescent hBMSCs. These findings suggest that metformin exerts antiaging function within the low concentration range by enhancing autophagy and exhibits potential benefits for clinical stem cell therapy by ameliorating the ex vivo replicative senescence of hBMSCs. [ABSTRACT FROM AUTHOR]