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External pressure and axial compression are common load cases for stiffened cylindrical shells in underwater structures. Once these two load cases are combined, the buckling behavior will become quite complex, especially when the external pressure is non-uniform. In this study, the influence of external pressure combined with axial compression on the post-buckling behavior of stiffened cylindrical shell is investigated. Then, a high-precision measuring system and loading system for non-uniform external pressure and axial compression is designed and constructed, and the buckling experiment of 1-m-diameter stiffened cylindrical shell under non-uniform external pressure and axial compression is carried out. The numerical results show that the proportion of axial compression is a crucial factor for the mode jumping of cylindrical shell, and it is overly conservative to evaluate the load-bearing capacity of cylindrical stiffened shell by the uniform external pressure. The comparison of experimental and numerical results demonstrates the accuracy and effectiveness of the experimental system. [Display omitted] • The post-buckling behavior of thin-walled shell under non-uniform external pressurewith axial compression is investigated. • A high-precision experimental facility for buckling test (measuring and loading system) is designed and constructed. • The complex post-buckling behavior of stiffened cylindrical shell is validated by the buckling test. [ABSTRACT FROM AUTHOR]

In this paper, the integrated design of curvilinearly grid-stiffened panels is investigated, including stiffener layout design and profile design. The layout design includes the curvilinear path and non-uniform distribution of stiffeners. Firstly, the path of curvilinear stiffeners is defined by the piecewise linear function, and the non-uniform distribution of curvilinear stiffener cluster is described by the proposed representation method based on the PCHIP interpolation function. In addition to the layout design, the variable profile design method of grid-stiffened structures is also proposed in this paper. The variations of the thickness and height of stiffeners are represented by curves respectively. Similarly, the variable profile design of stiffeners is realized by designing the curves. On this basis, various novel configuration of curvilinearly grid-stiffened panels can be obtained by the integrated layout and profile design. The effectiveness of the proposed integrated design framework is validated by numerical examples. Compared with the initial design, the final integrated design improves the critical buckling factor of the grid-stiffened panel by 73.09%, which shows a great design potential of this kind of variable-stiffness structure compared to constant-stiffness structures. Unlabelled Image • An efficient layout representation method of curvilinearly grid-stiffened panel with non-uniform distribution is proposed. • A concept of variable profile design of stiffeners based on interpolation curve is proposed. • Various novel configuration of curvilinearly grid-stiffened panels can be obtained by the integrated design framework. [ABSTRACT FROM AUTHOR]

As part of its commitment to the United Nations Framework Convention on Climate Change, the U.S. annually develops a national estimate of methane emissions from municipal solid waste (MSW) landfills by aggregating activity data from each facility. Since 2010, the U.S. has reported a 20 % decrease in MSW landfill emissions despite a 21 % increase in tons disposed. Operator-submitted data were investigated to understand the causes of this decline. In the U.S., operators of landfills with a gas collection and control system (GCCS) calculate their facility's emissions via two separate approaches - (1) first-order decay (FOD) and (2) collection efficiency assumption (CEA) - and select either result to feed into the annual inventory. The FOD model predicts methane generation proportional to waste disposal and that approach calculated a 19 % increase in total methane generated from 2010 to 2022, whereas generation via the CEA approach decreased by 8.9 %. The amount of measured methane collected has increased 7.5 % for the same years. Discrepancies between the two models' generated methane, assumed gas collection efficiencies, and oxidized methane compound into substantive differences in national estimates. Operators more frequently select the CEA method, which results in decreased national estimates. If only the FOD method was used, U.S. MSW landfill emissions would be 1.3-1.7 times greater than current estimates which is similar to recent extrapolations from remote sensing campaigns in the U.S. Both models contain parameters with large inherent uncertainty. Without measurement methods that continuously quantify both point-source and diffuse emissions, an assessment of either equation's accuracy cannot be made., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Combination drug therapy represents an effective strategy for treating certain drug-resistant and intractable cancer cases. However, determining the optimal combination of drugs and dosages is challenging due to clonal diversity in patients' tumors and the lack of rapid drug sensitivity evaluation methods. Microfluidic technology offers promising solutions to this issue. In this study, we propose a versatile microfluidic chip platform capable of integrating all processes, including dilution, treatment, and detection, for in vitro drug sensitivity assays. This platform innovatively incorporates several modules, including automated discrete drug logarithmic concentration generation, on-chip cell perfusion culture, and parallel drug treatments of cancer cell models. Moreover, it is compatible with microplate readers or high-content imaging systems for swift detection and automated monitoring, simplifying on-chip drug evaluation. Proof of concept is demonstrated by assessing the in vitro potency of two drugs, cisplatin, and etoposide, against the lung adenocarcinoma A549 cell line, under both single-drug and combination treatment conditions. The findings reveal that, compared to conventional microplate approaches with static cultivation, this on-chip automated perfusion bioassays yield comparable IC 50 values with lower variation and a 50 % reduction in drug preparation time. This versatile dilution-treatment-detection microfluidic platform offers a promising tool for rapid and precise drug assessments, facilitating in vitro drug sensitivity evaluation in personalized cancer chemotherapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The objective of this study is to investigate the fate and transport of per-polyfluoroalkyl substances (PFAS) through a high-density polyethylene (HDPE) geomembrane (GM) that is commonly used in landfill composite liner systems. Tests were conducted to measure the sorption and diffusion of per-polyfluoroalkyl substances (PFAS) with varying number of carbons in chain and functional groups on HDPE GM. Perfluoroalkyl carboxyl acids (PFCAs), perfluoroalkyl sulphonic acids (PFSAs), alkyl-sulfonamidoacetic acids (FOSAAs), fluorotelomer sulfonic acids (FtSAs), alkane sulfonamides (FOSA) and ether carboxylic acids (Gen X) were investigated in this study. The partition coefficients (K d ) on HDPE GM ranged from 3.8 to 98.3 L/kg. PFAS with amide and sulfonic functional groups showed stronger sorption than that of PFAS with carboxylic acid functional groups. Molecular weight directly affected the K d for long-chained PFAS whereas the K d of short-chained PFAS was not sensitive to molecular weight. The diffusion coefficients (D g ) of PFCAs and PFSAs through 0.1-mm HDPE GM were found to be in the orders of 10 -18 to 10 -17 m 2 /s. The D g decreased with increasing molar mass and were also observed to be dependent on the functional group. D g of PFSAs was lower than that of PFCAs for similar number of carbons in the chain. The estimated mass flux for PFAS in an intact 1.5-mm HDPE GM varied from 38.7 to 2080.8 ng/m 2 /year whereas the estimated diffusive breakthrough time for PFAS in intact 1.5-mm HDPE was 1526 years or longer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Hypergraphs have become an accurate and natural expression of high-order coupling relationships in complex systems. However, applying high-order information from networks to vital node identification tasks still poses significant challenges. This paper proposes a von Neumann entropy-based hypergraph vital node identification method (HVC) that integrates high-order information as well as its optimized version (semi-SAVC). HVC is based on the high-order line graph structure of hypergraphs and measures changes in network complexity using von Neumann entropy. It integrates s-line graph information to quantify node importance in the hypergraph by mapping hyperedges to nodes. In contrast, semi-SAVC uses a quadratic approximation of von Neumann entropy to measure network complexity and considers only half of the maximum order of the hypergraph's s-line graph to balance accuracy and efficiency. Compared to the baseline methods of hyperdegree centrality, closeness centrality, vector centrality, and sub-hypergraph centrality, the new methods demonstrated superior identification of vital nodes that promote the maximum influence and maintain network connectivity in empirical hypergraph data, considering the influence and robustness factors. The correlation and monotonicity of the identification results were quantitatively analyzed and comprehensive experimental results demonstrate the superiority of the new methods. At the same time, a key non-trivial phenomenon was discovered: influence does not increase linearly as the s-line graph orders increase. We call this the saturation effect of high-order line graph information in hypergraph node identification. When the order reaches its saturation value, the addition of high-order information often acts as noise and affects propagation.

Much efforts have been made to probe the mechanism underlying ischemic stroke (IS). This study was proposed to uncover the role of long non-coding RNA rhabdomyosarcoma 2 related transcript (RMST) in IS through microRNA-221-3p (miR-221-3p)/phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1)/transforming growth factor-β (TGF-β) axis. Neurological behavioral function, pathological changes in brain tissue, oxidative stress, and inflammation responses in middle cerebral artery occlusion (MCAO) mice were tested. RMST, miR-221-3p, PIK3R1, and TGF-β signaling-related protein expression in brain tissues of MCAO mice were detected. RMST and PIK3R1 were elevated, miR-221-3p was downregulated, and TGF-β pathway was activated in mice after MCAO. Restored miR-221-3p or depleted RMST improved neurological behavioral functions, relieved pathological injury in brain tissue, and repressed oxidative stress and inflammation in mice after MCAO. Depleted PIK3R1 or restored miR-221-3p offsets the negative effects of overexpressed RMST on mice with MCAO. The present work highlights that RMST augments IS through reducing miR-221-3p-mediated regulation of PIK3R1 and activating TGF-β pathway., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Treatment of antioxidants is necessary to protect ischemic stroke associated neuronal damage. Xanthohumol (XN), a natural flavonoid extracted from hops, has been reported to have potential function as an antioxidant and can be used for neuro protection. However, the role of XN in ischemic stroke remains unclear. Here, we studied the neuroprotective effects of XN through experimental stroke models. Middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD) was used as in vivo and in vitro model, respectively. We found that the treatment of XN improved MCAO-induced brain injury by reducing infarct size, improving neurological deficits, reversing neuronal damage, reducing oxidative stress injury and cell apoptosis. Further experimental studies showed that XN could revive neuronal apoptosis induced by OGD by preventing oxidative stress injury. In addition, our study suggested that these effects were related to the inhibition of phosphorylation of p38-MAPK and the mediation of nuclear Nrf2 activation. In conclusion, the neuroprotective effects of XN showed in this study make XN a promising supplement for ischemic stroke protection.

Objective: To analyze the characteristics of skeletal muscle cells gene markers in septic patients by using bioinformatics., Methods: The differential gene expression of marker microarrays (GSE13205) in skeletal muscle tissue of patients with sepsis was obtained from gene expression omnibus (GEO) database of National Center for Biotechnology Information (NCBI). Gene differential expression analysis was carried out using online GEO2R provided by NCBI. Data processing, analysis and mapping were carried out using online bioinformatics array research tool (BART) and Cytoscpe software, the software of the national resource for network biology. Functional annotation and pathway analysis of differential expression genes were performed using Kyoto encyclopedia of genes and genomes (KEGG) and gene ontology (GO) provided by the database for annotation, visualization and integrated discovery (DAVID), and protein interaction analysis was further performed in search tool for the retrieve of interacting genes/proteins (STRING-DB)., Results: The TOP250 genes were extracted from the GSE13205 dataset. A total of 242 differentially expressed genes were included in the analysis. Among them, 78 up-regulated genes and 164 down-regulated genes were identified. After extensive data analysis, these differentially expressed genes were enriched into different biological processes or subsets of molecular functions, mainly enriched in the positive and negative regulation of growth, mineral absorption and other pathways. The 14 most closely related genes among differentially expressed genes were identified from the protein interaction network., Conclusions: The differential expression genes in patients with sepsis were mainly concentrated on cell growth and apoptosis and mediating tumor-related immune function regulation.

Base on the data from fishery resources survey carried out in northern coastal waters in Yuhuan in November 2016 (autumn) and April 2017 (spring), we examined the niche and interspecific associations of major nekton by the methods of index of relative importance (IRI), niche breadth, niche overlap, the variance ratio (VR), X 2 -test, association coefficient (AC), Jaccard index (JI), point correlation coefficient (Φ) and Spearman rank correlation index. The ecological niche breadth of Portunus trituberculatus was the largest, with the absolute competitive advantage. The niche breadths of the important economic species Coilia nasus and Octopus variabilis were the smallest, which was at a weak competitive position. The niche overlap of the major nekton species in this area was uneven, possibly caused by the diversity of local environments. Overall interspecific associations indicated that insignificant negative correlation existed among major nekton species. All results of the X 2 -test, association coefficient (AC) and Jaccard index (JI) were consistent with that of overall interspecific associations, which indicated the independent trend among species. The correlation coefficients (Φ) and the Spearman rank correlation index revealed that the positive coupling pairs were more than the negative ones. It was due to the positive association among the other 14 species, caused by the spatial exclusion from large captured individuals of Muraenesox cinereus. According to the Spearman rank correlation and cluster analysis, 15 species could be divided into five ecological groups. The species within one ecological group had similar ecologically adaptable requirements of habitat, while the species from different ecological groups had different living habits and different ecological requirements.

The studies about the niche and interspecific association in China were mainly focused on the plants, birds and marine animals, and seldom on fish. Based on the fishery resources survey in spring (May) and autumn (September) in 2015, the associations among major fish species in south coastal waters of Wenzhou were investigated. The methods including niche breadth, niche overlap, variance ratio (VR), Χ 2 -test, association coefficient (AC), percentage of co-occurrence (PC) and point correlation coefficients (Ф) were used. The results showed that 47 fish species were identified, including 9 orders, 27 families and 41 genera. Four species were dominant species and 9 were important species, which together accounted for 17%. The niche breadth cluster analysis demonstrated two clearly identifiable ecological niches. The first one referred to wide niche that included Harpodon nehereus, Collichthys lucidus, Engraulis japonicas, Pampus echinogaster, Argyrosomus argentatus, Polynemus sextarius, Decapterus maruadsi and Trichiurus haumela, and the second one was narrow niche that included Muraenesox cinereus, Amblychaeturichthys hexanema, Cunoglossus robustus, Pseudosciaena polyactis and Ilisha elongate. The niche overlap value of the main fish was 0-0.90, indicating that there was difference in the resource utilization among the species. The ecological niche widths of C. robustus and M. cinereus were narrow, and the overlap values were high. This indicated that there was competition between these two species. The VR analysis revealed significant positive correlation among the main fish species. In view of the advantages of Ф value, which could reduce the impact of the analysis results of Χ 2 -test, AC and PC to the interspecific association, the Ф value method was selected in this study, and the association of 63 couples were positive. Both the interspecific association and ecological niche had different degrees of correlation with the stability of community structure and community succession.

A high-resolution, multi-line spectroscopic diagnostic system was used to detect two spectral line intensities in plasma jet simultaneously. The temperature profiles of an arc plasma jet issued into atmosphere and the concentrations of the air engulfment in the plasma jet were experimentally determined by means of the line absolute intensity method in this paper. The temperature profiles were obtained in two cases: the air engulfment in the plasma jet being considered and not being considered. The comparison of temperatures obtained in these two cases illustrates that the air engulfment in the plasma jet has considerable influence on spectroscopic diagnostic results. The neglect of the air engulfment brings on error in the temperature diagnostics with the absolute line intensity method. Especially in the region far away from the exit of the nozzle, the error is obvious.

The turbulence phenomenon is one of the most attractive characteristics of a DC arc plasma spraying jet. Most of the previous investigations believe that there is a laminar flow region in core of the jet. A spectrum diagnostic system has been built up in this paper to investigate these effects with the aid of high-speed digital camera. The FFT method has been applied to the analysis on the arc voltage and light signals. The influence of the arc behavior and the power supply on the jet is full-scale. It seems that there is not a laminar flow region in core of the jet. Moreover, from the light dynamic variation graph, the jet fluctuation due to the arc voltage behavior maybe is the dominant characteristic of the jet behavior.