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Since random uncertainty may cause severe aerodynamic performance fluctuations for the wing-mounted aircraft, the Gaussian process regression (GPR) surrogate model method based on was proposed. The strategy of adding sample points by active-learning method can effectively reduce model uncertainty and improve the accuracy of uncertainty prediction. Focusing on incoming flow with uncertainty, the polynomial chaos expansion (PCE) method based on Smolyak sparse grid and the GPR surrogate model method based on the strategy of adding sample points by active-learning method were used to analyze the uncertainty of the wing-body-nacelle-pylon geometry combined with the Sobol sensitivity analysis method. Results show that the uncertainty of angle of attack and Mach number will cause dramatic fluctuation in lift coefficient and drag coefficient of the wing-mounted aircraft under transonic condition. The fluctuation of lift coefficient is affected by angle of attack and Mach number, and the fluctuation of drag coefficient is mainly determined by Mach number.

In the rail vehicle manufacturing industry, effective information coordination between manufacturers and suppliers is crucial for supply chain performance. However, the presence of externalities can complicate the strategic choices of these stakeholders. This paper investigates the information coordination strategy between rail vehicle manufacturers and suppliers, considering the impact of externalities. By employing evolutionary game theory, we construct an interest matrix and analyze the equilibrium points and strategic choices under various scenarios. Our findings reveal that the degree of information cooperation, the distribution of cooperation income, and the unilateral opportunity income are the key factors influencing the choice of cooperation strategy. Specifically, a higher degree of information synergy and a more balanced distribution of cooperation benefits promote the adoption of cooperation strategies. Conversely, high unilateral opportunity benefits hinder cooperation. These insights provide valuable guidance for managers and decision-makers in the rail vehicle manufacturing industry to design effective information coordination mechanisms and enhance supply chain performance. By understanding the factors that drive cooperation and the strategic dynamics between manufacturers and suppliers, stakeholders can make informed decisions to foster collaboration and optimize their operations.

Ralstonia insidiosa can survive in a wide range of aqueous environments, including food processing areas, and is harmful to humans. It can induce Listeria monocytogenes to form suspended aggregates, resulting from the co-aggregation of two bacteria, which allows for more persistent survival and increases the risk of L. monocytogenes contamination. In our study, different groups of aggregates were analyzed and compared using Illumina RNA sequencing technology. These included R. insidiosa under normal and barren nutrient conditions and in the presence or absence of L. monocytogenes as a way to screen for differentially expressed genes (DEGs) in the process of aggregate formation. In addition, sterile supernatants of R. insidiosa were analyzed under different nutrient conditions using metabolomics to investigate the effect of nutrient-poor conditions on metabolite production by R. insidiosa. We also undertook a combined analysis of transcriptome and metabolome data to further investigate the induction effect of R. insidiosa on L. monocytogenes in a barren environment. The results of the functional annotation analysis on the surface of DEGs and qPCR showed that under nutrient-poor conditions, the acdx, puuE, and acs genes of R. insidiosa were significantly upregulated in biosynthetic processes such as carbon metabolism, metabolic pathways, and biosynthesis of secondary metabolites, with Log2FC reaching 4.39, 3.96, and 3.95 respectively. In contrast, the Log2FC of cydA, cyoB, and rpsJ in oxidative phosphorylation and ribosomal pathways reached 3.74, 3.87, and 4.25, respectively. Thirty-one key components were identified while screening for differential metabolites, which mainly included amino acids and their metabolites, enriched to the pathways of biosynthesis of amino acids, phenylalanine metabolism, and methionine metabolism. Of these, aminomalonic acid and Proximicin B were the special components of R. insidiosa that were metabolized under nutrient-poor conditions.

Abstract Background Although cholesterol metabolism is a common pathway for the development of antitumor drugs, there are no specific targets and drugs for clinical use. Here, based on our previous study of sterol O-acyltransferase 1 (SOAT1) in hepatocelluar carcinoma, we sought to screen an effective targeted drug for precise treatment of hepatocelluar carcinoma and, from the perspective of cholesterol metabolism, clarify the relationship between cholesterol regulation and tumorigenesis and development. Methods In this study, we developed a virtual screening integrated affinity screening technology for target protein drug screening. A series of in vitro and in vivo experiments were used for drug activity verification. Multi-omics analysis and flow cytometry analysis were used to explore antitumor mechanisms. Comparative analysis of proteome and transcriptome combined with survival follow-up information of patients reveals the clinical therapeutic potential of screened drugs. Results We screened three compounds, nilotinib, ABT-737, and evacetrapib, that exhibited optimal binding with SOAT1. In particular, nilotinib displayed a high affinity for SOAT1 protein and significantly inhibited tumor activity both in vitro and in vivo. Multi-omics analysis and flow cytometry analysis indicated that SOAT1-targeting compounds reprogrammed the cholesterol metabolism in tumors and enhanced CD8+ T cells and neutrophils to suppress tumor growth. Conclusions Taken together, we reported several high-affinity SOAT1 ligands and demonstrated their clinical potential in the precision therapy of liver cancer, and also reveal the potential antitumor mechanism of SOAT1-targeting compounds. Graphical Abstract

The aim of this work is to develop a green route for platinum nanoparticles (PtNPs) biosynthesized using Cordyceps flower extract and to evaluate their antioxidant activity and antibacterial activity. Different characterization techniques were utilized to characterize the biosynthetic PtNPs. The results showed that PtNPs were spherical particles covered with Cordyceps flower extract. The average particle size of PtNPs in Dynamic Light Scattering was 84.67 ± 5.28 nm, while that of PtNPs in Transmission Electron Microscope was 13.34 ± 4.06 nm. Antioxidant activity of PtNPs was evaluated by DPPH free radical scavenging ability test. The results showed that the antioxidant activity was positively correlated with the concentration of PtNPs, the DPPH scavenging efficiency of PtNPs (0.50–125.00 μg/mL) was 27.77–44.00%. In addition, the morphological changes of four kinds of bacteria (Escherichia coli, Salmonella typhimurium, Bacillus subtilis, Staphylococcus aureus) exposed to PtNPs were observed by scanning electron microscope. The results showed that the antibacterial activity of PtNPs against Gram-negative bacteria was stronger than that of Gram-positive bacteria.

Lysozyme acts as a kind of cationic antimicrobial protein and effectively hydrolyzes bacterial peptidoglycan to have a bactericidal effect, which also plays an important role in protecting eggs from microbial contamination. Dermacoccus abyssi HZAU 226, a Gram-positive bacterium isolated from spoiled eggs, has egg white and lysozyme tolerance, but its survival mechanism is unknown, especially from a transcriptomics point of view. In this study, the high lysozyme tolerance of D. abyssi HZAU 226 was characterized by three independent experiments, and then the Illumina RNA-seq was used to compare the transcriptional profiles of this strain in Luria–Bertani (LB) medium with and without 5 mg/mL lysozyme to identify differentially expressed genes (DEGs); 1024 DEGs were identified by expression analysis, including 544 up-regulated genes and 480 down-regulated genes in response to lysozyme treatment. The functional annotation analysis results of DEGs showed that these genes were mainly involved in glutathione biosynthesis and metabolism, ion transport, energy metabolism pathways, and peptidoglycan biosynthesis. This study is the first report of bacterial-related lysozyme RNA-seq, and our results help in understanding the lysozyme-tolerance mechanism of bacteria from a new perspective and provide transcriptome resources for subsequent research in related fields.

With the rapid development and widespread adoption of wireless sensor networks (WSNs), security has become an increasingly prominent problem. How to establish a session key in node communication is a challenging task for WSNs. Considering the limitations in WSNs, such as low computing capacity, small memory, power supply limitations and price, we propose an efficient identity-based key management (IBKM) scheme, which exploits the Bloom filter to authenticate the communication sensor node with storage efficiency. The security analysis shows that IBKM can prevent several attacks effectively with acceptable computation and communication overhead.

With the wide adoption of wireless sensor network (WSN), security problems emerge as a challenging issue because of the limited computational power and energy of the sensor nodes. Furthermore, the deployment of WSN in the hostile area with a large number of nodes also poses a threat. In this paper, we proposed a new efficient key management scheme based on Elliptic Curve Cryptography (ECC) and AVL tree for large scale WSNs. In our scheme the Elliptic Curve Paillier Encryption (ECPE) cryptography is adopted for communication and the AVL tree is used to store the neighbors' ID and public key. The number of keys used in our scheme is smaller than the proposed schemes as we store these keys using AVL tree to shorten the search time. Regular key updates are also designed to further improve the security of the whole network. Our scheme has a good scalability where the node addition and deletion are supported. Experimental results and analysis show our scheme can significantly reduce the energy consumed by the node and reduce the memory and computational overhead.

Metabolic pathways in eubacteria and archaea often are encoded by operons and/or gene clusters (genome neighborhoods) that provide important clues for assignment of both enzyme functions and metabolic pathways. We describe a bioinformatic approach (genome neighborhood network; GNN) that enables large scale prediction of the in vitro enzymatic activities and in vivo physiological functions (metabolic pathways) of uncharacterized enzymes in protein families. We demonstrate the utility of the GNN approach by predicting in vitro activities and in vivo functions in the proline racemase superfamily (PRS; InterPro IPR008794). The predictions were verified by measuring in vitro activities for 51 proteins in 12 families in the PRS that represent ~85% of the sequences; in vitro activities of pathway enzymes, carbon/nitrogen source phenotypes, and/or transcriptomic studies confirmed the predicted pathways. The synergistic use of sequence similarity networks3 and GNNs will facilitate the discovery of the components of novel, uncharacterized metabolic pathways in sequenced genomes.

Nanotip arrays with high aspect ratio, which have attracted much attention due to their potential applications, have been fabricated by many methods. Dry etching combined with self-assembly masks is widely used because of the convenience of dry etching and high throughput of self-assembly. In this paper, we report a method combining Cesium Chloride (CsCl) self-assembly with inductively coupled plasma (ICP) dry etching to fabricate silicon nanotip arrays with high aspect ratio and silicon nanotip arrays with aspect ratio 15 have been achieved after optimization of all parameters.

Using a large-scale "genomic enzymology" approach, we (i) assigned novel ATP-dependent four-carbon acid sugar kinase functions to members of the DUF1537 protein family (domain of unknown function; Pfam families PF07005 and PF17042) and (ii) discovered novel catabolic pathways for D-threonate, L-threonate, and D-erythronate. The experimentally determined ligand specificities of several solute binding proteins (SBPs) for TRAP (tripartite ATP-independent permease) transporters for four-carbon acids, including D-erythronate and L-erythronate, were used to constrain the substrates for the catabolic pathways that degrade the SBP ligands to intermediates in central carbon metabolism. Sequence similarity networks and genome neighborhood networks were used to identify the enzyme components of the pathways. Conserved genome neighborhoods encoded SBPs as well as permease components of the TRAP transporters, members of the DUF1537 family, and a member of the 4-hydroxy-L-threonine 4-phosphate dehydrogenase (PdxA) oxidative decarboxylase, class II aldolase, or ribulose 1,5-bisphosphate carboxylase/oxygenase, large subunit (RuBisCO) superfamily. Because the characterized substrates of members of the PdxA, class II aldolase, and RuBisCO superfamilies are phosphorylated, we postulated that the members of the DUF1537 family are novel ATP-dependent kinases that participate in catabolic pathways for four-carbon acid sugars. We determined that (i) the DUF1537/PdxA pair participates in a pathway for the conversion of D-threonate to dihydroxyacetone phosphate and CO2 and (ii) the DUF1537/class II aldolase pair participates in pathways for the conversion of D-erythronate and L-threonate (epimers at carbon-3) to dihydroxyacetone phosphate and CO2. The physiological importance of these pathways was demonstrated in vivo by phenotypic and genetic analyses. [ABSTRACT FROM AUTHOR]

The genome of Labrenzia aggregata IAM 12614 encodes an uncharacterized member of the muconate lactonizing enzyme (MLE) subgroup of the enolase superfamily (UniProt ID A0NXQ8). The gene encoding A0NXQ8 is located between genes that encode members of the proline racemase superfamily, 4R-hydroxyproline 2-epimerase (UniProt ID A0NXQ7; 4HypE) and frans-3-hydroxy-L-proline dehydratase (UniProt ID A0NXQ9; t3LHypD). A0NXQ8 was screened with a library of proline analogues; two reactions were observed with ris-3-hydroxy-L-proline (c3LHyp), competing 2-epimerization to trans-3-hydroxy-D-proline (1,1-proton transfer) and dehydration to Δ¹-pyrroline-2-carboxylate (β-elimination; c3LHyp dehydratase), with eventual total dehydration. The genome context encoding A0NXQ8 both (l) confirms its novel c3LHyp dehydratase function and (2) provides evidence for metabolic pathways that allow L. aggregata to utilize several isomeric 3- and 4-hydroxyprolines as sole carbon sources. [ABSTRACT FROM AUTHOR]

Pyramids and nanoholes are integrated together to form a micro–nano-texture on silicon surface in order to suppress reflection for silicon solar cell application. The nanoholes are formed by inductively coupled plasma (ICP) dry etching employing a nanoporous aluminum (Al) mask which is fabricated by caesium chloride (CsCl) nanoislands lift-off technique. Reflection of less than 4% can be reached by pyramid–nanohole texture, which is much lower than that from pure pyramids or nanoholes texture. Higher short circuit current density (Jsc) and photovoltaic conversion efficiency (PCE) are obtained for the solar cell with pyramid–nanohole texture due to its better antireflection. The average diameter and depth of the nanoholes affect the solar cell properties. The smaller and deeper nanoholes can suppress reflection a lot, but meanwhile, the formation of them means more crystal lattice defects generated from ICP etching. An optimized diameter of 800 nm and depth of 1μm for the nanoholes are obtained in our experiments to get the best photovoltaic performance that is a PCE of 14.89% with a Jsc of 38.25mAcm−2 and an open circuit voltage (Voc) of 544.8mV. [ABSTRACT FROM AUTHOR]