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1.
J Transl Med ; 22(1): 445, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735939

RESUMO

BACKGROUND: Endometriosis, characterized by the presence of active endometrial-like tissues outside the uterus, causes symptoms like dysmenorrhea and infertility due to the fibrosis of endometrial cells, which involves excessive deposition of extracellular matrix (ECM) proteins. Ubiquitination, an important post-transcriptional modification, regulates various biological processes in human diseases. However, its role in the fibrosis process in endometriosis remains unclear. METHODS: We employed multi-omics approaches on two cohorts of endometriosis patients with 39 samples. GO terms and KEGG pathways enrichment analyses were used to investigate the functional changes involved in endometriosis. Pearson's correlation coefficient analysis was conducted to explore the relationship between global proteome and ubiquitylome in endometriosis. The protein expression levels of ubiquitin-, fibrosis-related proteins, and E3 ubiquitin-protein ligase TRIM33 were validated via Western blot. Transfecting human endometrial stroma cells (hESCs) with TRIM33 small interfering RNA (siRNA) in vitro to explore how TRIM33 affects fibrosis-related proteins. RESULTS: Integration of proteomics and transcriptomics showed genes with concurrent change of both mRNA and protein level which involved in ECM production in ectopic endometria. Ubiquitylomics distinguished 1647 and 1698 ubiquitinated lysine sites in the ectopic (EC) group compared to the normal (NC) and eutopic (EU) groups, respectively. Further multi-omics integration highlighted the essential role of ubiquitination in key fibrosis regulators in endometriosis. Correlation analysis between proteome and ubiquitylome showed correlation coefficients of 0.32 and 0.36 for ubiquitinated fibrosis proteins in EC/NC and EC/EU groups, respectively, indicating positive regulation of fibrosis-related protein expression by ubiquitination in ectopic lesions. We identified ubiquitination in 41 pivotal proteins within the fibrosis-related pathway of endometriosis. Finally, the elevated expression of TGFBR1/α-SMA/FAP/FN1/Collagen1 proteins in EC tissues were validated across independent samples. More importantly, we demonstrated that both the mRNA and protein levels of TRIM33 were reduced in endometriotic tissues. Knockdown of TRIM33 promoted TGFBR1/p-SMAD2/α-SMA/FN1 protein expressions in hESCs but did not significantly affect Collagen1/FAP levels, suggesting its inhibitory effect on fibrosis in vitro. CONCLUSIONS: This study, employing multi-omics approaches, provides novel insights into endometriosis ubiquitination profiles and reveals aberrant expression of the E3 ubiquitin ligase TRIM33 in endometriotic tissues, emphasizing their critical involvement in fibrosis pathogenesis and potential therapeutic targets.


Assuntos
Endometriose , Fibrose , Proteômica , Ubiquitinação , Humanos , Feminino , Endometriose/metabolismo , Endometriose/patologia , Endometriose/genética , Adulto , Ontologia Genética , Proteoma/metabolismo , Multiômica
2.
J Integr Plant Biol ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656698

RESUMO

Leaf senescence is an essential physiological process related to grain yield potential and nutritional quality. Green leaf duration (GLD) after anthesis directly reflects the leaf senescence process and exhibits large genotypic differences in common wheat; however, the underlying gene regulatory mechanism is still lacking. Here, we identified TaNAM-A1 as the causal gene of the major loci qGLD-6A for GLD during grain filling by map-based cloning. Transgenic assays and TILLING mutant analyses demonstrated that TaNAM-A1 played a critical role in regulating leaf senescence, and also affected spike length and grain size. Furthermore, the functional divergences among the three haplotypes of TaNAM-A1 were systematically evaluated. Wheat varieties with TaNAM-A1d (containing two mutations in the coding DNA sequence of TaNAM-A1) exhibited a longer GLD and superior yield-related traits compared to those with the wild type TaNAM-A1a. All three haplotypes were functional in activating the expression of genes involved in macromolecule degradation and mineral nutrient remobilization, with TaNAM-A1a showing the strongest activity and TaNAM-A1d the weakest. TaNAM-A1 also modulated the expression of the senescence-related transcription factors TaNAC-S-7A and TaNAC016-3A. TaNAC016-3A enhanced the transcriptional activation ability of TaNAM-A1a by protein-protein interaction, thereby promoting the senescence process. Our study offers new insights into the fine-tuning of the leaf functional period and grain yield formation for wheat breeding under various geographical climatic conditions.

3.
J Colloid Interface Sci ; 666: 346-354, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603877

RESUMO

The unique electronic and crystal structures of rare earth metals (RE) offer promising opportunities for enhancing the hydrogen evolution reaction (HER) properties of materials. In this work, a series of RE (Sm, Nd, Pr and Ho)-doped Rh@NSPC (NSPC stands for N, S co-doped porous carbon nanosheets) with sizes less than 2 nm are prepared, utilizing a simple, rapid and solvent-free joule-heat pyrolysis method for the first time. The optimized Sm-Rh@NSPC achieves HER performance. The high-catalytic performance and stability of Sm-Rh@NSPC are attributed to the synergistic electronic interactions between Sm and Rh clusters, leading to an increase in the electron cloud density of Rh, which promotes the adsorption of H+, the dissociation of Rh-H bonds and the release of H2. Notably, the overpotential of the Sm-Rh@NSPC catalyst is a mere 18.1 mV at current density of 10 mAcm-2, with a Tafel slope of only 15.2 mV dec-1. Furthermore, it exhibits stable operation in a 1.0 M KOH electrolyte at 10 mA cm-2 for more than 100 h. This study provides new insights into the synthesis of composite RE hybrid cluster nanocatalysts and their RE-enhanced electrocatalytic performance. It also introduces fresh perspectives for the development of efficient electrocatalysts.

4.
Immunology ; 172(3): 469-485, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38544333

RESUMO

Endometriosis is defined as an oestrogen-dependent and inflammatory gynaecological disease of which the pathogenesis remains unclear. This study aimed to investigate the cellular heterogeneity and reveal the effect of CD8+ T cells on the progress of endometriosis. Three ovarian endometriosis patients were collected, and single-cell RNA sequencing (scRNA-seq) progressed and delineated the cellular landscape of endometriosis containing five cell clusters. The endometrial cells (EMCs) were the major component, of which the mesenchymal cells were preponderant and characterized with increased inflammation and oestrogen synthesis in endometriosis. The proportion of T cells, mainly CD8+ T cells rather than CD4+, was reduced in endometriotic lesions, and the cytokines and cytotoxicity of ectopic T cells were depressed. CD8+ T cells depressed the proliferation of ESCs through inhibiting CDK1/CCNB1 pathway to arrest the cell cycle and triggered inflammation through activating STAT1 pathway. Correspondingly, the coculture with ESCs resulted in the dysfunction of CD8+ T cells through upregulating STAT1/PDCD1 pathway and glycolysis-promoted metabolism reprogramming. The endometriotic lesions were larger in nude mouse models with T-cell deficiency than the normal mouse models. The inhibition of T cells via CD90.2 or CD8A antibody increased the endometriotic lesions in mouse models, and the supplement of T cells to nude mouse models diminished the lesion sizes. In conclusion, this study revealed the global cellular variation of endometriosis among which the cellular count and physiology of EMCs and T cells were significantly changed. The depressed cytotoxicity and aberrant metabolism of CD8+ T cells were induced by ESCs with the activation of STAT1/PDCD1 pathway resulting in immune survival to promote endometriosis.


Assuntos
Linfócitos T CD8-Positivos , Endometriose , Fator de Transcrição STAT1 , Células Estromais , Endometriose/imunologia , Endometriose/patologia , Endometriose/metabolismo , Feminino , Linfócitos T CD8-Positivos/imunologia , Humanos , Animais , Camundongos , Células Estromais/imunologia , Células Estromais/metabolismo , Fator de Transcrição STAT1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Endométrio/imunologia , Endométrio/patologia , Modelos Animais de Doenças , Transdução de Sinais , Camundongos Nus , Adulto , Proteína Quinase CDC2/metabolismo , Técnicas de Cocultura , Citocinas/metabolismo
5.
J Clin Pharmacol ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38375685

RESUMO

Ceftazidime/avibactam (CAZ/AVI) is a combination of a well-known third-generation, broad-spectrum cephalosporin with a new beta-lactamase inhibitor that has been approved for the treatment of various infectious diseases (especially multidrug-resistant Gram-negative bacterial infections) by the Food and Drug Administration (FDA). The current study extensively assessed CAZ/AVI-related adverse events (AEs) in the real world through data mining of the FDA Adverse Event Reporting System (FAERS) database to better understand toxicities. The signals of CAZ/AVI-related AEs were quantified using disproportionality analyses, including the reporting odds ratio, the proportional reporting ratio, the Bayesian confidence propagation neural network, and the multi-item gamma Poisson shrinker algorithms. Out of 10,114,815 records retrieved from the FAERS database, 628 cases were identified, where CAZ/AVI was implicated as the primary suspect drug. A total of 61 preferred terms with significant disproportionality that simultaneously met the criteria of all four algorithms were retained. Several unexpected safety signals may also occur, including melena, hypernatremia, depressed level of consciousness, brain edema, petechiae, delirium, and shock hemorrhagic. The median onset time for AEs associated with CAZ/AVI was 4 days, with most cases occurring within 3 days after CAZ/AVI initiation.

6.
Polymers (Basel) ; 15(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38006157

RESUMO

Hypersonic vehicles encounter hostile service environments of thermal/mechanical/chemical coupling, so thermal protection materials are crucial and essential. Ceramizable composites have recently attracted intensive interest due to their ability to provide large-area thermal protection for hypersonic vehicles. In this work, a novel ceramizable composite of quartz fiber/benzoxazine resin modified with fused SiO2 and h-BN was fabricated using a prepreg compression molding technique. The effects of the fused SiO2 and h-BN contents on the thermal, mechanical, and ablative properties of the ceramizable composite were systematically investigated. The ceramizable composite with an optimized amount of fused SiO2 and h-BN exhibited superb thermal stability, with a peak degradation temperature and residue yield at 1400 °C of 533.2 °C and 71.5%, respectively. Moreover, the modified ceramizable composite exhibited excellent load-bearing capacity with a flexural strength of 402.2 MPa and superior ablation resistance with a linear ablation rate of 0.0147 mm/s at a heat flux of 4.2 MW/m2, which was significantly better than the pristine quartz fiber/benzoxazine resin composite. In addition, possible ablation mechanisms were revealed based on the microstructure analysis, phase transformation, chemical bonding states, and the degree of graphitization of the ceramized products. The readily oxidized pyrolytic carbon (PyC) and the SiO2 with a relatively low melting point were converted in situ into refractory carbide. Thus, a robust thermal protective barrier with SiC as the skeleton and borosilicate glass as the matrix protected the composite from severe thermochemical erosion and thermomechanical denudation.

7.
J Colloid Interface Sci ; 650(Pt A): 742-751, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37441967

RESUMO

Layered transition metal oxides have the greatest potential for commercial application as cathode materials for sodium-ion batteries. However, transition metal oxides inevitably undergo an irreversible oxygen loss process during cycling, which leads to structural changes in the material and ultimately to severe capacity degradation. In this work, using density function theory (DFT) calculations, the Ni-O bond is revealed to be the weakest of the M-O bonds, which may lead to structural failure. Herein, the synergistic surface CeO2 modification and the trace doping of Ce elements stimulate oxygen redox and improve its reversibility, thus improving the structural stability and electrochemical performance of the material. Theoretical calculations prove that Na0.67Mn0.7Ni0.2Co0.1O2 (MNC) obtains electrons from CeO2, avoiding destruction of the Ni-O bond by over-energy released during the charging process and inhibiting oxygen loss. The capacity retention was 77.37% for 200 cycles at 500 mA g-1, compared to 33.84% for the unmodified Na0.67Mn0.7Ni0.2Co0.1O2. Overall, the present work demonstrates that the synergistic effect of surface coating and doping is an effective strategy for realizing tuning oxygen release and high electrochemical performance.

8.
Eur J Sport Sci ; 23(12): 2291-2298, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37338107

RESUMO

ABSTRACTPrevious studies have shown that the school-based physical activity programme entitled "11 for Health" has been effective in improving the physical fitness, well-being and overall health profile of European children. The main purpose of the present study was to examine whether the "11 for Health" programme can have a positive impact on the physical fitness of primary school pupils in China. A total of 124 primary school pupils aged 9-11 years were included in the experiment, randomly divided into the experimental group (EG, n = 62) and the control group (CG, n = 62). EG carried out three weekly 35-minute sessions of small-sided football for a total of 11 weeks. All data were analysed by a mixed ANOVA with the Student-Newman-Keuls post hoc test. The results showed greater improvements (p<0.001) in EG than CG in relation to systolic blood pressure (-2.9 vs +2.0 mmHg). Moreover, greater improvements (all p<0.05) were observed in postural balance (13 vs 0%), standing long jump (5.0 vs 0.5%), 30-metre sprint (4.1 vs 1.3%) and Yo-Yo IR1C running performance (17% vs 6%). In both EG and CG, physical activity enjoyment was observed to be higher (P<0.05) compared to the start of the intervention with increases of 3.7 and 3.9 AU respectively. In conclusion, the study revealed that the "11 for Health" programme has positive effects on aerobic and muscular fitness, and it appears to be a relevant tool in the physical activity promotion in the Chinese school system.


The combined health education and football programme "11 for Health" was tested for the first time in the Chinese school system.The "11 for Health" programme had positive effects on the cardiovascular and muscular fitness of 9­11-year-old Chinese school children.The "11 for Health" programme seems to be a relevant tool for physical activity promotion in the Chinese school system, but further studies are warranted to test the implementation potential of the programme and the broadspectrum effects on physical activity enjoyment, wellbeing and health profile.


Assuntos
Futebol Americano , Corrida , Criança , Humanos , Aptidão Física/fisiologia , Exercício Físico , Teste de Esforço
9.
Am J Reprod Immunol ; 89(3): e13659, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36412044

RESUMO

BACKGROUND: Endometriosis is a benign gynecological disease with the feature of estrogen dependence and inflammation. The function of autophagy and the correlation with inflammation were not yet revealed. METHODS: Autophagosomes were detected by transmission electron microscopy. Gene Expression Omnibus (GEO) database was referred to analyze the expression of autophagy-related genes. Quantification of mRNA and protein expression was examined by qRT-PCR and Western Blot. Immunohistochemistry was performed to explore the expression of proteins in tissues. The mouse model of endometriosis was performed to analyze the autophagic activity and effect of LXA4. RESULTS: The expression of autophagy-related genes in endometriotic lesions were unusually changed. The number of autophagosomes and LC3B-II expression was diminished, and p62 was increased in ectopic lesions from both patients and mice. Interleukin 1ß (IL1ß) attenuated the expression of LC3B and promoted the level p62. The autophagy activator MG-132 upregulated the expression of LC3B and reduced IL1ß, IL6, and p62. LXA4 reversed the inhibitory effect of IL1ß on the expression of LC3B and p62, and blocking the receptor of LXA4 AhR (aryl hydrocarbon receptor) resulted in the incapacitation of LXA4 to influence the effect of IL1ß. LXA4 depressed the phosphorylation of AKT and mTOR to against IL1ß, and blocking AhR negatively regulated the effect of LXA4 on AKT/mTOR pathway. LXA4 reduced the ectopic lesions and the expression of IL1ß and p62, but enhanced LC3B-II in endometriotic mouse models. CONCLUSION: In endometriosis, increased inflammation of ectopic lesions prominently depresses autophagy. LXA4 could regulate autophagy by suppressing inflammatory response through AhR/AKT/mTOR pathway.


Assuntos
Endometriose , Lipoxinas , Humanos , Feminino , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Endometriose/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Endométrio/patologia , Serina-Treonina Quinases TOR/metabolismo , Lipoxinas/metabolismo , Inflamação/metabolismo , Autofagia
10.
Colloids Surf B Biointerfaces ; 220: 112893, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36270139

RESUMO

Endometriosis is an inflammation-dependent disorder characterized by the abnormal growth of endometrium-like lesions. In recent years, there is a great deal of interest in the development of anti-inflammatory therapy. Herein, an acid-sensitive calcium carbonate nanoparticle (CaNP) incorporated BML-111 (BML@CaNP) was prepared. BML@CaNP acted as a Ca2+ nanomodulator for efferocytosis (macrophages engulf apoptotic cells). Specifically, BML@CaNP induced the apoptosis of endometriotic stromal cells and enhanced the efferocytosis of macrophages. In addition, the particle can also deliver BML to the ectopic lesion for resolving the inflammatory response. In vivo BML@CaNP effectively suppressed lesion growth in endometriosis mice model, which could be attributed to the enhancing efferocytosis of cells and the lower levels of inflammatory factors in peritoneal fluid. In addition, these nanoparticles did not show side effects. In all, we provide a new anti-inflammatory strategy by both enhancing efferocytosis and resolving inflammation for the treatment of endometriosis.


Assuntos
Endometriose , Nanopartículas Multifuncionais , Camundongos , Humanos , Animais , Feminino , Endometriose/tratamento farmacológico , Fagocitose , Macrófagos , Inflamação/tratamento farmacológico
11.
ACS Appl Mater Interfaces ; 14(40): 45494-45502, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36170546

RESUMO

In recent years, rechargeable aqueous zinc-ion batteries (ZIBs) have shown extraordinary potential due to their safety, nontoxicity, sustainable zinc resources, and low price. However, the lack of suitable cathode materials hinders the development of ZIBs. Recently, layered phosphates have been widely used as cathode materials. As one typical phosphate cathode, vanadium oxyphosphate (VOPO4) has inherently low electronic conductivity and structural dissolution in electrochemical reactions, limiting its development. To solve these problems, VOPO4/C is prepared by combining multifunctional carbon material with a VOPO4 interlayer and an external surface, which not only improves the electronic conductivity of the composite material but also effectively inhibits the dissolution of VOPO4 in the electrolyte. As a result, the prepared VOPO4/C could deliver a reversible capacity of 140 mA h g-1 at a current density of 100 mA g-1. Furthermore, the rate performance of the VOPO4/C composite has also been improved significantly. In the process of charging and discharging, zinc ions in the composite show perfect intercalate and deintercalate performance.

12.
Water Res ; 224: 119121, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126626

RESUMO

Sedimentary denitrification and anaerobic ammonium oxidation (anammox) are two microbially-mediated nitrogen removal pathways with distinct climatic feedbacks. Estuaries receive large fluxes of anthropogenic nitrogen and serve as hotspots for nitrogen loss. Applying 15N isotope pairing technique and sediment intact core incubation in two subtropical estuaries, the Yangtze River Estuary (YRE) and Jiulong River Estuary (JRE), we show that denitrification predominates the sedimentary nitrogen loss with a minor contribution (8.6 ± 7.5%) from anammox. Particulate organic matter degradation sustains the sedimentary nitrogen removal linking the nitrogen transformations between water column and sediment. Our results indicate that estuarine sediments exhibit high areal nitrogen removal rate, but play a relatively weak role in eliminating the nitrogen inputted from river basin due to the limited area. The riverine excess nitrogen will eventually enter into the adjacent continental shelf and be removed via phytoplankton assimilation-sedimentation-degradation-coupled nitrification-denitrification. In addition, sedimentary denitrification causes 1.8 ± 2.2% of nitrogen flow towards nitrous oxide (N2O) production and the derived N2O release flux accounts for 59% and 65% of the daily sea-air N2O emission in the YRE and JRE, respectively. These findings contribute to a better understanding of estuarine sedimentary nitrogen removal and associated climate feedbacks, and to the parameterization of Earth system models.


Assuntos
Compostos de Amônio , Estuários , Desnitrificação , Retroalimentação , Sedimentos Geológicos , Nitrogênio/metabolismo , Óxido Nitroso/análise , Rios , Água
13.
Polymers (Basel) ; 14(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35890560

RESUMO

Carbon fiber fabric-reinforced phenolic resin composites are widely used as thermal protection materials for thermal protection systems in hypersonic vehicles and capsules. In this work, carbon fiber fabric-reinforced boron phenolic resin composites modified with MoSi2 and B4C were prepared via a compression molding technique. The high-temperature performance of the composites as well as the oxidation behavior of the carbon fibers was studied. The results indicate that the incorporation of B4C improves the performance of composites at high temperatures. The residual weight rate of composites with 15 phr B4C (BP-15) sufficiently increased from 23.03% to 32.91% compared with the composites without B4C (BP-0). After being treated at 1400 °C for 15 min, the flexural strength of BP-15 increased by 17.79% compared with BP-0. Compared with BP-0, the line ablation rate and mass ablation rate of BP-15 were reduced by 53.96% and 1.56%, respectively. In addition, MoSi2 and B4C particles had a positive effect on the oxidation of carbon fibers in the composites. After treatment at 1400 °C, the diameter of the as-received carbon fiber was reduced by 31.68%, while the diameter of the carbon fiber in BP-0 and BP-15 decreased by 15.12% and 6.14%, respectively. At high temperatures, the liquid B2O3 from B4C and MoSi2-derived complex-phase ceramics (MoB, MoB2, Mo2C, Mo4.8Si3C0.6) acted as an oxygen barrier, effectively mitigating the oxidation degree of the carbon fibers.

14.
Nanomaterials (Basel) ; 12(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35683751

RESUMO

Development of high-performance graphene-based microwave absorbing materials with low density and strong absorption is of great significance to solve the growing electromagnetic pollution. Herein, a controllable open-cell structure is introduced into graphene aerogels by the graphene oxide (GO) Pickering emulsion. The open-cell graphene aerogel (OCGA) with multiple microstructures shows a significantly enhanced microwave absorption ability without any additions. A high microwave absorption performance with the minimum value of reflection loss (RLmin) of -51.22 dB was achieved, while the material density was only 4.81 mg/cm3. Moreover, by means of centrifugation, the graphene cells were arranged by their diameter, and a gradient, open-cell graphene structure was first fabricated. Based on this unique structure, an amazing microwave absorption value of -62.58 dB was reached on a condition of ultra-low graphene content of 0.53 wt%. In our opinion, such excellent microwave absorption performance results from multiple reflection and well-matched impedance brought by the open-cell and gradient structure, respectively. In addition, the structural strength of the OCGA is greatly improved with a maximum increase of 167% due to the introduction of cell structure. Therefore, the OCGAs with the gradient structure can be an excellent candidate for lightweight, efficient microwave absorption materials.

15.
Dalton Trans ; 51(23): 9116-9126, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35666657

RESUMO

The oxygen evolution reaction (OER), as the rate-determining step of electrochemical water splitting, is extremely crucial, and thus it is a requisite to engineer feasible and effective electrocatalysts to shrink the reaction energy barrier and accelerate the reaction. Herein, monodisperse Mn3O4 nanoparticles on a PANI substrate were synthesized by polymerization and in situ oxidation. Combining Mn3O4 nanoparticles and PANI fibers can not only maximize the strong coupling effect and synergistic effect but also construct a well-defined three-dimensional structure with extensive exposed active sites, where the permeation and adherence of the electrolyte are made exceedingly feasible, thus displaying excellent OER activity. Benefiting from the outstanding structural stability, the resulting Mn3O4/PANI/NF is able to deliver a low overpotential of 262 mV at a current density of 10 mA cm-2, which outperforms the commercial RuO2 catalyst (275 mV) as well as presently reported representative Mn-based and PANI-based electrocatalysts and state-of-the-art OER electrocatalysts. The synthetic method for Mn3O4/PANI not only provides a brand-new avenue for the rational design of inorganic material/conductive polymer composites but also broadens the understanding of the mechanism of Mn-based catalysts for highly enhanced OER.

16.
Materials (Basel) ; 15(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35629695

RESUMO

The reliable mechanical properties of ceramizable silicone rubber composites during pyrolysis are necessary for their application in the fire-resistant fields. The effects of liquid-phase amount on the mechanical properties of silicone rubber composites are investigated. The results show a positive correlation between the liquid-phase amount and the flexural strength of the residual products pyrolysis below 800 °C. The nano-γ-Al2O3 in the fillers reacts with liquid B2O3 to form aluminum borate above 800 °C, which consumes the liquid phase and strengthens the residual products to a certain extent. Increasing the B2O3 addition and introducing nano-γ-Al2O3 can control the liquid-phase amount in the range of 15% to 30%, which makes the composites have better residual strength and support performance. The residual strength of composites pyrolysis at 500 °C to 1000 °C is higher than 2.50 MPa, and the maximum is up to 18.7 MPa at 1000 °C.

17.
Front Psychiatry ; 12: 630876, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744804

RESUMO

Background: Previous studies have identified differentially expressed microRNAs in autism spectrum disorder (ASD), however, results are discrepant. We aimed to systematically review this topic and perform bioinformatic analysis to identify genes and pathways associated with ASD miRNAs. Methods: Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses, we searched the Web of Science, PubMed, Embase, Scopus, and OVID databases to identify all studies comparing microRNA expressions between ASD persons and non-ASD controls on May 11, 2020. We obtained ASD miRNA targets validated by experimental assays from miRTarBase and performed pathway enrichment analysis using Metascape and DIANA-miRPath v3. 0. Results: Thirty-four studies were included in the systematic review. Among 285 altered miRNAs reported in these studies, 15 were consistently upregulated, 14 were consistently downregulated, and 39 were inconsistently dysregulated. The most frequently altered miRNAs including miR-23a-3p, miR-106b-5p, miR-146a-5p, miR-7-5p, miR-27a-3p, miR-181b-5p, miR-486-3p, and miR-451a. Subgroup analysis of tissues showed that miR-146a-5p, miR-155-5p, miR-1277-3p, miR-21-3p, miR-106b-5p, and miR-451a were consistently upregulated in brain tissues, while miR-4742-3p was consistently downregulated; miR-23b-3p, miR-483-5p, and miR-23a-3p were consistently upregulated in blood samples, while miR-15a-5p, miR-193a-5p, miR-20a-5p, miR-574-3p, miR-92a-3p, miR-3135a, and miR-103a-3p were consistently downregulated; miR-7-5p was consistently upregulated in saliva, miR-23a-3p and miR-32-5p were consistently downregulated. The altered ASD miRNAs identified in at least two independent studies were validated to target many autism risk genes. TNRC6B, PTEN, AGO1, SKI, and SMAD4 were the most frequent targets, and miR-92a-3p had the most target autism risk genes. Pathway enrichment analysis showed that ASD miRNAs are significantly involved in pathways associated with cancer, metabolism (notably Steroid biosynthesis, Fatty acid metabolism, Fatty acid biosynthesis, Lysine degradation, Biotin metabolism), cell cycle, cell signaling (especially Hippo, FoxO, TGF-beta, p53, Thyroid hormone, and Estrogen signaling pathway), adherens junction, extracellular matrix-receptor interaction, and Prion diseases. Conclusions: Altered miRNAs in ASD target autism risk genes and are involved in various ASD-related pathways, some of which are understudied and require further investigation.

18.
Polymers (Basel) ; 13(8)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33916970

RESUMO

In this paper, a new polyhedral oligomeric silsesquioxane containing a phenol group (POSS-Phenol) is prepared through the Michael addition reaction, which is added to the synthesis of phenolic resin as a functional monomer. Infrared spectroscopy (IR) is used to demonstrate the chemistry structure of the synthesized POSS modified phenolic resin. After introducing POSS into the resole, a comprehensive study is conducted to reveal the effects of POSS on the thermal degradation of phenolic resin. First, thermal degradation behaviors of neat phenolic resin and modified phenolic resin are carried out by thermogravimetric analysis (TGA). Then, the gas volatiles from thermal degradation are investigated by thermogravimetric mass spectrometry (TG-MS). Finally, the residues after thermal degradation are characterized by X-ray diffraction (XRD). The research indicates that POSS modified phenolic resin shows a better thermal stability than neat phenolic resin, especially at high temperatures under air atmosphere. On the one hand, the introduction of the POSS group can effectively improve the release temperature of oxygen containing volatiles. On the other hand, the POSS group forms silica at high temperatures under air, which can effectively inhibit the thermal oxidation of phenolic resin and make phenolic resin show a better high-temperature oxidation resistance.

19.
Polymers (Basel) ; 13(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925265

RESUMO

In order to study the dynamic mechanical properties of styrene-acrylic latex with a core/shell structure, a variety of latexes were synthesized by semi-continuous seeded emulsion polymerization based on "particle design" with the same material. The latexes were characterized by rotary viscosimeter, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), dynamic mechanical analysis (DMA), and universal testing machine. The effects of difference at the glass transition temperature (Tg) of core and shell and the introduction of the "transition layer" on the damping and mechanical properties of latex film were studied. The results indicate that as the Tg of core and shell gets closer, the better the compatibility of core and shell, from phase separation to phase continuity. Furthermore, the introduction of the "transition layer" can effectively improve the tensile strength and tan δ (max) of the latex film. The tensile strength and maximum loss factor (f = 1 Hz) of latex with the "transition layer" increased by 36.73% and 29.11% respectively compared with the latex without the "transition layer". This work provides a reference for the design of emulsion for damping coating.

20.
Chemistry ; 27(35): 9044-9053, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33861489

RESUMO

Oxygen evolution reaction (OER) is considered as a critical half-cell reaction of water splitting, the kinetics of which is sluggish even not favored, thus requiring highly active electrocatalysts to shrink the reaction energy barrier and improve the energy conversion efficiency. In this study, In-situ generated trimetallic molybdate nanoflowers on Ni foam by a straightforward and time-saving solvothermal method assisted with microwave, not only bring synergistic effect into full play between multiple metals, but also construct a well-defined nanoflower-like structure accompanied by larger specific area (273.3 m2 g-1 ) and smaller size than the pristine NiMoO4 . The resulting Ni0.9 Al0.1 MoO4 -NF requires a relatively low overpotential of 266 mV for OER at 10 mA cm-2 , which outperforms commercial RuO2 catalysts (274 mV). Such excellent performance compares favorably to most previously reported NiMoO4 -based electrocatalysts for OER. This work not only supplies a facile method to construct a well-defined nanoflower-like structure on foam, but also broadens our horizons into the mechanism of OER in alkaline conditions.

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