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Aiming at the problems of aerodynamic resistance, noise, and operation safety of rubber windshields, a new mechanical external windshield for the train was designed. Based on the model of three car high-speed train, the frequency spectrum characteristics of aerodynamic noise were analyzed under 300 km/h, 400 km/h, and 500 km/h working conditions, and the aerodynamic characteristics and flow field distribution of mechanical external windshield were compared with those of the existing windshields. The results show that under the same speed, the pressure distribution of the mechanical external windshield was relatively gentle, and the velocity loss of the vortex generated in the cavity was small. The radiated noise from the dipole sound source on the train surface decreased with the increase of the distance from the vehicle body. Also, as the frequency increased, the noise sound pressure presented a downward trend, and the distribution tended to be uniform gradually. In directivity, the sound pressure on both sides of the windshield has a certain symmetry. The sound pressure fluctuation was consistent with the frequency change, and the maximum sound pressure occurred at the position where the curvature change at the upper end of the windshield was the largest. The research results in this paper can provide some reference for the design of the train windshield structure and the reduction of train resistance and noise.

ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) is a well-recognized cause of bacterial pneumonia in general. The gut microbiota and their metabolic byproducts act as important modulators of the gut-lung axis. Our investigation indicates a significant reduction in the abundance of butyrate producer unclassified_f__Lachnospiraceae within the lung and gut microbiota of MRSA-infected mice, as well as a significant decrease in the levels of butyrate in gut and serum. Additionally, supplementary sodium butyrate (NaB) significantly reduces bacteria colonization in the lung, suppresses pro-inflammatory cytokines expression, and enhances lung tissue morphology in MRSA-treated mice. The results of high-throughput 16S rDNA sequencing demonstrate that NaB reshapes the gut and lung microbiota by drastically reducing the abundance of potential pathogenic bacteria in the gut and cell motility-related bacteria in the lung, which are induced by MRSA. Moreover, NaB treatment augments the gut and circulating butyrate levels. Mechanistically, NaB promotes signal transducer and activator of transcription 1 (STAT1) acetylation and inhibits dimer STAT1 phosphorylation by reducing the binding of histone deacetylase 3 to STAT1, thereby altering alveolar macrophage polarization toward the M2 phenotype. Collectively, our findings suggest that NaB exerts a preventative effect against MRSA-induced pneumonia by enhancing the gut-lung microbiota and promoting macrophage polarization toward an anti-inflammatory M2 phenotype. The prophylactic administration of NaB emerges as a promising strategy for combating MRSA pneumonia. IMPORTANCE Pneumonia caused by methicillin-resistant Staphylococcus aureus (MRSA) continues to carry a high burden in terms of mortality. With the roles of gut microbiota in mediating lung diseases being gradually uncovered, the details of the molecular mechanism of the “gut-lung axis” mediated by beneficial microorganisms and small-molecule metabolites have gradually attracted the attention of researchers. However, further studies are still necessary to determine the efficacy of microbial-based interventions. Our findings indicate that sodium butyrate (NaB) alleviates MRSA-induced pulmonary inflammation by improving gut-lung microbiota and promoting M2 polarization of alveolar macrophages. Therefore, the preventive administration of NaB might be explored as an effective strategy to control MRSA pneumonia.

Developing a bio-sensor for rapid detection of biological hydrogen sulfide (bio-H2S) is of great significance to human health. Metal-oxide-semiconductor heterostructure based sensors have attracted extensive attention due to their large area, order structure, fast response, and high sensitivity. In this study, we prepared the Cu2O/NiO nanoarrays by the two-dimensional electrochemical in-situ assembly deposition method for bio-H2S detection. The sensors based on Cu2O/NiO nanoarrays were measured by a customized test system. The experimental results indicated that the sensor exhibited excellent sensitivity, low detection level and good selectivity to bio-H2S in the range of 1 ∼ 200 µmol/L. Moreover, we proposed that the superior performance of the nanoarrays was mainly attributed to the synergistic effects of Cu2O/NiO heterostructure as well as vulcanization reaction of Cu2O. The results demonstrate that the Cu2O/NiO nanoarrays based sensor is a potential candidate for high performance bio-H2S sensor.

Summary: The therapeutic administration of recombinant proteins is utilized in a multitude of research studies for treating various diseases. In this study, we investigate the therapeutic potential of Orosomucoid 2 (Orm2), an acute phase protein predominantly secreted by hepatocytes, for treating non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). Our results show that high Orm2 expression prevents high-fat-diet (HFD)-induced obesity in mice. Pharmacological administration of recombinant ORM2 protein ameliorates hepatic steatosis, inflammation, hepatocyte injury, and fibrosis in mouse livers afflicted by NAFLD and NASH under dietary stress. Orm2 knockout mice develop spontaneous obesity under a regular diet and exacerbate HFD-induced steatosis, steatohepatitis, and fibrosis. Mechanistically, Orm2 deletion activates the Erk1/2-PPARγ-Cd36 signaling pathway, increasing fatty acid uptake and absorption in hepatocytes and mice. Overall, our findings underscore the critical role of Orm2 in preventing NASH and associated NAFLD in the context of obesity.

Preferences or dislikes for specific numbers are ubiquitous in human society. In traditional Chinese culture, people show special preference for some numbers, such as 6, 8, 10, 100, 200, etc. By analyzing the data of 6.8 million users of Sina Weibo, one of the largest online social media platforms in China, we discover that users exhibit a distinct preference for the number 200, i.e., a significant fraction of users prefer to follow 200 friends. This number, which is very close to the Dunbar number that predicts the cognitive limit on the number of stable social relationships, motivates us to investigate how the preference for numbers in traditional Chinese culture is reflected on social media. We systematically portray users who prefer 200 friends and analyze their several important social features, including activity, popularity, attention tendency, regional distribution, economic level, and education level. We find that the activity and popularity of users with the preference for the number 200 are relatively lower than others. They are more inclined to follow popular users, and their social portraits change relatively slowly. Besides, users who have a stronger preference for the number 200 are more likely to be located in regions with underdeveloped economies and education. That indicates users with the preference for the number 200 are likely to be vulnerable groups in society and are easily affected by opinion leaders.

The nanostructures with uniform long-range ordered structure are of crucial importance for performance standardization of high-quality surface-enhanced Raman scattering (SERS) spectra. In this paper, we described the fabrication and SERS properties of Au decorated Cu (Au@Cu) nanoarrays. The Cu nanoarrays with uniform long-range ordered structure were first synthesized by in-situ electrochemistry assembly on insulated substrate. The Cu nanoarrays can reach a size of centimeters with strictly periodic nano-microstructure, which is beneficial for the production and performance standardization of SERS substrates. Then Au nanoparticals were decorated on the Cu nanoarrays by galvanic reaction without any capping agent. The obtained Au@Cu nanoarrays exhibit excellent SERS activity for 4-Mercaptopyridine, and the sensitivity limit is as low as 10−8 M. Therefore, this facile route provides a useful platform for the fabrication of SERS substrates based on nano ordered arrays.

The treatment of sediments is a key challenge with regards to the treatment of black and odorous water. At present, the sediments of black and odorous water bodies are mostly treated using dredging, and the sediments need to be effectively treated to reduce the secondary pollution to the environment. Chemical process is widely used in the treatment of black and odorous sediments due to its obvious and fast treatment effect. In this study, three chemical reagents, namely sodium persulfate, calcium oxide and hydrogen peroxide, were selected to find their optimal dosages to treat the sediments. The results show that persulfate had the most favorable treatment effect on sediments, and exhibited the optimum removal effect for water content, organic matter, total nitrogen, ammonia nitrogen, total phosphorus and heavy metal content of sediments. The optimal dosage of sodium persulfate and calcium oxide was 6 g/L each, while that of hydrogen peroxide was 30 mL/L. For the combination of different reagents, the combined effect of sodium persulfate and hydrogen peroxide was the most favorable. When the dosages of sodium persulfate and hydrogen peroxide were 4.5 g/L and 7.5 mL/L, respectively, the removal rates of total nitrogen, ammonia nitrogen, total phosphorus, cadmium, chromium, nickel, lead, water content and organic matter in sediments reached the values of 69.53%, 74.58%, 77.23%, 39.21%, 41.01%, 43.72% and 21.74%, 21.33% and 2.4%, respectively. [ABSTRACT FROM AUTHOR]

Protein arginine methyltransferase-1 (PRMT1) is an important epigenetic regulator of cell function and contributes to inflammation and remodeling in asthma in a cell type-specific manner. Disease-specific expression patterns of microRNAs (miRNA) are associated with chronic inflammatory lung diseases, including asthma. The de novo synthesis of miRNA depends on the transcription of primary miRNA (pri-miRNA) transcript. This study assessed the role of PRMT1 on pri-miRNA to mature miRNA process in lung epithelial cells. Human airway epithelial cells, BEAS-2B, were transfected with the PRMT1 expression plasmid pcDNA3.1-PRMT1 for 48 h. Expression profiles of miRNA were determined by small RNA deep sequencing. Comparing these miRNAs with datasets of microarrays from five asthma patients (Gene Expression Omnibus dataset), 12 miRNAs were identified that related to PRMT1 overexpression and to asthma. The overexpression or knockdown of PRMT1 modulated the expression of the asthma-related miRNAs and their pri-miRNAs. Coimmunoprecipitation showed that PRMT1 formed a complex with STAT1 or RUNX1 and thus acted as a coactivator, stimulating the transcription of pri-miRNAs. Stimulation with TGF-b1 promoted the interaction of PRMT1 with STAT1 or RUNX1, thereby upregulating the transcription of two miRNAs: let-7i and miR-423. Subsequent chromatin immunoprecipitation assays revealed that the binding of the PRMT1/STAT1 or PRMT1/RUNX1 coactivators to primary let-7i (pri-let-7i) and primary miR (pri-miR) 423 promoter was critical for pri-let-7i and primiR-423 transcription. This study describes a novel role of PRMT1 as a coactivator for STAT1 or RUNX1, which is essential for the transcription of pri-let-7i and pri-miR-423 in epithelial cells and might be relevant to epithelium dysfunction in asthma. [ABSTRACT FROM AUTHOR]

A current-sensing atomic force microscopy is used for measuring the nanoscale capacitance spectroscopy of the two-dimensional electron gas (2DEG) of AlGaN/GaN heterostructures. The current-sensing method has detected the change in Schottky barriers of the probe-sample contact, which has affected the measurement of the threshold voltage of 2DEG.