Publications by authors named "Mingkai Xu"

Gas-phase heterogeneous catalytic CO hydrogenation to commodity chemicals and fuels via surface frustrated Lewis pairs is a growing focus of scientific and technological interest. Traditional gas-phase heterogeneous surface frustrated Lewis pair catalysts primarily involve metal oxide-hydroxides (MOH•••M). An avenue to improve the process performance metrics lies in replacing the Lewis base MOH with a stronger alternative; an intriguing example being the amine MNH in metal nitrides.

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Background: High-voltage workers often experience fatigue due to the physically demanding nature of climbing in dynamic and complex environments, which negatively impacts their motor and mental abilities. Effective monitoring is necessary to ensure safety.

Methods: This study proposed an experimental method to quantify fatigue in climbing operations.

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Article Synopsis
  • * Oral SEC2 is detected in various parts of the body and promotes the growth and differentiation of key immune cells, resulting in increased production of important immune molecules like cytokines and immunoglobulin A.
  • * SEC2 also improves gut health by enhancing the intestinal barrier and positively influencing gut microbiota, suggesting its potential as an oral immunostimulant for boosting immunity and supporting cancer treatment.
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Sunlight-responsive minerals contribute significantly to biogeochemical cycles by activating oxygen (O) to generate reactive oxygen species (ROS). However, the role of crystal water, incorporated into minerals through hydration during rock cycles, in O activation remains largely unexplored. Here, we construct tungstite models containing oxygen vacancies to elucidate the modulation of mineral-based ROS dynamics by the synergy between oxygen vacancy and crystal water.

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Manipulating exciton dissociation and charge-carrier transfer processes to selectively generate free radicals of more robust photocatalytic oxidation capacity for mineralizing refractory pollutants remains challenging. Herein, we propose a strategy by simultaneously introducing the cyano-group and Na into graphitic carbon nitride (CN) to obtain CN-Cy-Na, which makes the charge-carrier transfer pathways the dominant process and consequently achieves the selective generation of free radicals. Briefly, the cyano-group intensifies the local charge density of CN, offering a potential well to attract the hole of exciton, which accelerates the exciton dissociation.

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Micro/nanoplastics in the environment can be ingested by organisms and spread throughout the food chain, ultimately posing a threat to human health. However, the risk of continuous oral exposure in mammals remains unresolved. In this study, we utilized a continuous gavage mouse model to investigate the potential intestinal risks associated with oral exposure to polystyrene micro/nanoplastics (PS-MNPs) with environmentally relevant concentrations.

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Background: To accurately measure students' science, technology, engineering and mathematics (STEM) career interest, researchers must get inside the 'black box' to understand students' conceptualizations of STEM careers.

Aims: The aim of Study 1 was to explore whether students' conceptualizations of STEM included medical careers. The aim of Study 2 was to explore whether predictors of STEM career interest (e.

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As a biological macromolecule, the superantigen staphylococcal enterotoxin C2 (SEC2) is one of the most potent known T-cell activators, and it induces massive cytotoxic granule production. With this property, SEC2 and its mutants are widely regarded as immunomodulating agents for cancer therapy. In a previous study, we constructed an MHC-II-independent mutant of SEC2, named ST-4, which exhibits enhanced immunocyte stimulation and antitumor activity.

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Asthe most-used pesticides in the agricultural production process, herbicides are mainly applied to protect crops from weeds. However, with the increased global demand for food, the dosage of herbicides is rising annually, and the efficacy of herbicides is getting stronger, which can cause some environmental issues including the accumulation, migration and transformation, and toxic effects of herbicides in agricultural soils. According to the characteristics of herbicide contamination and regional agricultural production, developing green and low-carbon technologies to reduce the ecological risks of herbicides to the soil-crop systems is a current concern in the ecological environment field.

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Chlorimuron-ethyl is a widely used herbicide in agriculture. However, uncontrolled chlorimuron-ethyl application causes serious environmental problems. Chlorimuron-ethyl can be effectively degraded by microbes, but the underlying molecular mechanisms are not fully understood.

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Chlorimuron-ethyl is a commonly used sulfonylurea herbicide, and its long-term residues cause serious environmental problems. Biodegradation of chlorimuron-ethyl is effective and feasible, and many degrading strains have been obtained, but still, the genes and enzymes involved in this degradation are often unclear. In this study, whole-genome sequencing was performed on chlorimuron-ethyl-degrading strain, Chenggangzhangella methanolivorans CHL1.

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Excessive application of the herbicide chlorimuron-ethyl (CE) severely harms subsequent crops and poses severe risks to environmental health. Therefore, methods for efficiently decreasing and eliminating CE residues are urgently needed. Microbial consortia show potential for bioremediation due to their strong metabolic complementarity and synthesis.

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As a newly emerging hazardous material, airborne nanoplastics are easily inhaled and accumulated in human and animal alveoli. We previously found that polystyrene nanoplastics (PS-NPs) induced apoptosis and inflammation of human alveolar epithelial A549 cells, implying they increase the risk of pulmonary fibrosis. In this study, we investigated whether PS-NPs induce epithelial-to-mesenchymal transition (EMT), the prelude to lung fibrosis, in A549 cells.

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In this study, triazine-degrading strain SB5 was isolated and screened from the activated sludge contaminated with atrazine by enrichment culture technology. Based on its morphology and 16S rRNA gene analysis, strain SB5 was initially identified as sp. It contained the atrazine-degrading genes , and .

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Influenza pandemics pose public health threats annually for lacking vaccine that provides cross-protection against novel and emerging influenza viruses. Combining conserved antigens that induce cross-protective antibody responses with epitopes that activate cross-protective T cell responses might be an attractive strategy for developing a universal vaccine. In this study, we constructed a recombinant protein named NMHC that consists of influenza viral conserved epitopes and a superantigen fragment.

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Nanoplastics can be ingested by organisms and penetrate biological barriers to affect multiple physiological functions. However, few studies have focused on the effects of nanoplastics on the mammalian immune system. We evaluated the effects and underlying mechanism of nanoplastics of varying particle sizes and surface charges on murine splenic lymphocytes.

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As a member of superantigens, Staphylococcal Enterotoxin C2 (SEC2) can potently activate T cells expressing specific Vβ repertoires and has been applied in clinic for tumor immunotherapy in China for more than 20 years. However, excessive activation of T cells by over-stimulation with superantigen are always followed by eliciting regulatory T cells (Tregs) induction and functional immunosuppression, which brings uncertainties to SEC2 application in tumor immunotherapy. In this study, we found that SEC2 could induce CD4CD25Foxp3 Tregs from the murine splenocytes in dose and time related manners.

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Bacterial superantigens potently activate conventional T-cells to induce massive cytokine production and mediate tumor cell death. To engineer superantigens for immunotherapy against tumors in clinic, we previously generated SAM-1, a staphylococcal enterotoxins C2 (SEC2) mutant, that exhibited significantly reduced toxicity but maintained the superantigen activity in animal models. This present study aimed to investigate whether SAM-1 activates T cells and induces apoptosis in human tumor cells.

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CD8 T cells can switch between fatty acid catabolism and mitochondrial energy metabolism to sustain expansion and their cytotoxic functions. ST-4 is a TCR-enhanced mutant derived from superantigen staphylococcal enterotoxin C2 (SEC2), which can hyperactivate CD4 T cells without MHC class II molecules. However, whether ST-4/SEC2 can enhance metabolic reprogramming in CD8 T cells remains poorly understood.

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Solid tumors are intrinsically resistant to immunotherapy because of the major challenges including the immunosuppression and poor penetration of drugs and lymphocytes into solid tumors due to the complicated tumor microenvironment (TME). Our previous study has created a novel superantigen mutant ST-4 to efficiently active the T lymphocytes and alleviate immune suppression. In the present study, to accumulate ST-4 into the TME, we constructed a recombinant protein, ST-4-iRGD, by fusing ST-4 to a tumor-homing peptide, iRGD.

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Purpose: To develop an automated framework for sleep stage scoring from PSG via a deep neural network.

Methods: An automated deep neural network was proposed by using a multi-model integration strategy with multiple signal channels as input. All of the data were collected from one single medical center from July 2017 to April 2019.

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As a kind of newly emerging pollutant, nanoplastics are easily to be ingested by organisms, and cause severe damage to biological functions because of their small size, high specific surface area, and strong biological penetration. Recently, there are increasing reports of numerous airborne microplastics, including polystyrene (PS), being detected in atmospheric samples, which implies a potential risk to the human respiratory system. In this work, we evaluated the effects of polystyrene nanoparticles of two different sizes (PS-NP25: 25 nm diameter and PS-NP70: 70 nm diameter) on the human alveolar epithelial A549 cell line including internalization, cell viability, cell cycle, apoptosis, and associated gene transcription and protein expression.

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SEC2, a major histocompatibility complex class II (MHC II)-dependent T-cell mitogen, binds MHC II and T-cell receptor (TCR) Vβs to induce effective co-stimulating signals for clonal T-cell expansion. We previously characterized a SEC2 mutant with increased recognition of TCR Vβs, ST-4, which could intensify NF-κB signaling transduction, leading to IL-2 production and T-cell activation. In this study, we found that in contrast to SEC2, ST-4 could induce murine CD4 T-cell proliferation in a Vβ8.

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As a kind of superantigen, staphylococcal enterotoxin C2 (SEC2) is well known as a powerful immunomodulator. However, most previous studies about SEC2 focus on its T cell activating characters. But the direct effect of SEC2 on antigen-presenting cells (APCs) which are important for the T cell activation is not clearly.

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