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Pneumonia is a common infectious disease of the respiratory system in children. It often leads to death in children by causing acute lung injury. Fibroblast growth factor 21 (FGF21) is a peptide hormone that plays an important role in the regulation of energy homeostasis. This study aimed to investigate the role of FGF21 in alleviating the lipopolysaccharide (LPS)- induced human pulmonary microvascular endothelial cell (HPMEC) injury, as well as the underlying mechanism. The expression of sirtuin 1 (SIRT1), NF-[kappa]B p65, Ac-NF-[kappa]B p65, apoptosis-related proteins, tight junction proteins and adhesion molecules in HPMECs were analyzed by Western blotting. The viability and apoptosis of HPMECs were detected by CCK-8 and TUNEL assays. Lactate dehydrogenase level and levels of inflammatory factors were respectively determined by assay kits. The mRNA expression of adhesion molecules in HPMECs was analyzed by RT-qPCR. As a result, SIRT1 expression was decreased and the expression of NF-[kappa]B p65 and Ac-NF-[kappa]B p65 were increased in LPS-induced HPMECs, which were reversed by recombinant FGF21 (rFGF21). rFGF21 increased the viability and inhibited the apoptosis, inflammatory response, permeability, and release of cell adhesion molecules of LPS-induced HPMECs. In addition, EX527 as SIRT1 inhibitor could reverse the effect of rFGF21 on LPS- induced HPMECs. In conclusion, FGF21 improved LPS-induced HPMEC dysfunction and inflammatory response through SIRT1-mediated NF-[kappa]B deacetylation. Key words: fibroblast growth factor21, pulmonary microvascular endothelial cell dysfunction, inflammatory response, sirtuin 1, NF-[kappa]B deacetylation La pneumonie est une maladie infectieuse de l'appareil respiratoire qui est frequente chez les enfants. Elle entraine souvent des lesions pulmonaires aigues, qui peuvent etre mortelles chez eux. Le facteur de croissance des fibroblastes 21 (FGF21) est une hormone peptidique qui joue un role important dans l'homeostasie energetique. Cette etude portait sur le role du FGF21 dans l'attenuation des lesions des cellules endotheliales des microvaisseaux pulmonaires humains (CEMPH) entrainees par les lipopolysaccharides (LPS), de meme que sur le mode d'action sous-jacent. Nous avons evalue l'expression de SIRT1, du NF-[kappa]B p65, de l'Ac-NF-[kappa]B p65, de proteines liees a l'apoptose, des proteines de jonctions serrees et des molecules d'adherence dans les CEMPH. Nous avons evalue la vitalite et l'apoptose des CEMPH a l'aide des epreuves de CCK-8 et de TUNEL. Nous avons evalue les taux de LDH et de facteurs inflammatoires a l'aide de kits biochimiques. Nous avons etudie l'expression en ARNm de molecules d'adherence dans les CEMPH a l'aide de la technique de PCR quantitative par transcriptase inverse. Resultat, nous avons observe une diminution de l'expression de SIRT1 avec une augmentation de l'expression du NF-[kappa]B p65 et de l'Ac-NF-[kappa]B p65 dans les CEMPH exposees aux LPS, phenomenes qui s'inversaient sous rFGF21. Le rFGF21 entrainait une augmentation de la vitalite des CEMPH exposees aux LPS, avec une inhibition de l'apoptose, de la reaction inflammatoire, de la permeabilite et de la liberation de molecules d'adherence cellulaire. De plus, le EX527, inhibiteur de SIRT1, pouvait entrainer une inversion de l'effet du rFGF21 sur les CEMPH exposees aux LPS. En conclusion, le FGF21 permettait d'attenuer le dysfonctionnement des CEMPH exposees aux LPS et la reaction inflammatoire par l'intermediaire de la desacetylation du facteur NF-[kappa]B mediee par SIRT1. [Traduit par la Redaction] Mots-cles : facteur de croissance des fibroblastes 21, dysfonctionnement des cellules endotheliales des microvaisseaux pulmonaires, reaction inflammatoire, SIRT1, desacetylation du facteur NF-[kappa]B, Introduction Pneumonia is a common infectious disease of the respiratory system in children. In addition to respiratory symptoms such as cough and sputum, pneumonia can also lead to multi-system complications [...]

This paper proposes a novel physics-based equivalent circuit model of the lithium-ion battery for electric vehicle applications that has comprehensive electrochemical significance and an acceptable level of complexity. Initially, the physics-based extended single particle (ESP) model is improved by adding a correction term to mitigate its voltage bias. Then, the equivalent circuit model based on the improved extended single particle (ECMIESP) model is derived. In this model, the surface state of charge (SOC) of solid particles is approximated using a capacity and multi first-order resistance-capacity equivalent circuits with only two lumped parameters. The overpotential of electrolyte diffusion is approximated using a first-order resistance-capacitance equivalent circuit. The electrochemical reaction overpotential is characterized by a nonlinear resistance. The voltage accuracies of ECMIESP and conventional 2RC equivalent circuit model (ECM2RC) are compared across the entire SOC range under various load profiles. The results demonstrate that the ECMIESP model outperforms ECM2RC model, particularly at low SOC or when the electrochemical reaction overpotential exceeds 50 mV. For instance, the ECMIESP model shows an 820.4 mV reduction in voltage error compared to the ECM2RC model at the endpoint during a 2C constant current discharge test. Lastly, the ECMIESP model was used for SOC estimation with extended Kalman filter, resulting in significantly improved accuracy compared to the conventional ECM2RC model. Therefore, the ECMIESP model has great potential for real-time applications in enhancing voltage and SOC estimation precision. [ABSTRACT FROM AUTHOR]

Electroreduction of CO2 into formic acid (HCOOH) is of great economical value and potential for industrialization. However, it is still a substantial challenge due to the lack of efficient catalysts with simultaneously high activity, selectivity, and durability. Herein, a single‐atom bismuth loaded on N‐doped hollow carbon sphere (Bi–SA/NHCS) catalyst is reported and its catalytic activity and selectivity are modulated by changing the coordination structure of Bi center. The obtained Bi–SA/NHCS with a Bi–N3 site exhibits significantly enhanced electrocatalytic activity and selectivity of HCOOH synthesis from CO2 reduction. The HCOOH production rate achieves 16.2 mmol L−1 h−1 cm−2 at a current density of 20 mA cm−2, and its Faradaic efficiency remains 100% during a long‐term reaction. The HCOOH production rate normalized by catalyst loading is at a molar level of nearly 1.5 mol h−1 gcat−1. The production rate and Faradaic efficiency of HCOOH electrosynthesis on Bi–SA/NHCS are significantly boosted as compared with other catalysts reported in the literature. Experimental and density‐functional theory results demonstrate that the boosted activity and selectivity of HCOOH synthesis owe to the electronic structure modulation to the Bi center via threefold coordinated N‐ligands, leading to a proper binding energy of HOCO* intermediates. [ABSTRACT FROM AUTHOR]

To study the sampling and compilation method of load spectrum of passenger car transmission,taking a certain type of front-engine,front-wheel-drive passenger car transmission as an example,according to different road conditions,the road random load of this passenger car transmission is collected.According to the characteristics of the load,the amplitude cycle counting method is employed to complete the statistical treatment for various time dependent loads tested in the road test.The design load spectrum of the passenger car transmission is compiled.The sampling and compilation method of load spectrum of the passenger car transmission is established.The method can provide accurate design input conditions for passenger car transmission,and provide a reference for accurate fatigue life prediction and fatigue test.

BACKGROUND Weed seeds in rice‐wheat continuous cropping fields spread via flowing water during irrigation of the rice crop. However, the ability of their adaptation to water dispersal and their structural mechanisms remain unclear. One hundred and ten species of weed seeds from 35 families were selected for this study. Seed slices were made through freeze sectioning to observe and assess the proportions of parenchyma, aerenchyma and lignified tissue. Microstructure and morphological traits, such as relative size and appendages were integrated into an analysis. RESULTS: Multivariate statistical analysis showed that floating time was significantly positively correlated with the shape, aerenchyma and parenchyma of the weed seeds and negatively with lignified tissue. Cluster analysis divided all the tested seeds into four categories. The first category was super floating weeds, which had a large proportion of parenchyma or air chamber and floated on water surfaces for > 400 h, including 16 species; the second category was strong floating weeds, which had a flat shape, parenchyma or air chamber structures and floated for 120 to 400 h, including 17 species; the third category was floating weeds, which were usually dense in structure with a floating time < 120 h, including 78 species; the fourth category showed no floating ability with a large size and mass, and dense structures including seven species. CONCLUSION: Most weeds had floating ability, which was closely related to the adaptability of their anatomical structures. This study takes an insight into understanding ecological adaptation of weeds and the sustainable ecological weed control through removing floating weed seeds. [ABSTRACT FROM AUTHOR]