Minicomposite, as the elementary scale of the full-scale ceramic matrix composites (CMCs), has been commonly considered as the appropriate specimen type for basic research on environmental behavior ...of CMCs due to its simple structure, low fabrication cost and mature modeling foundation. However, its size is too small relative to the full-scale CMCs, resulting in the existing environmental performance testing equipment developed for macrocomposites not matching it in all respects. In order to fill this gap, a compact environmental performance testing apparatus, which consists mainly of a two-zone furnace, gas humidifier, control system and a pair of quartz tubes and high temperature specimen grips, has been designed and built here. Creep test of SiC fiber at elevated temperatures from 800 to 1100 °C with water vapor and oxidation test of SiC/SiC minicomposite at 1316 °C in stress-free wet oxygen environment were carried out respectively to verify the accuracy and reliability of the rig. With the apparatus, the environmental degradation mechanism of CMCs can be quantitatively analyzed, which lays a foundation for the service life prediction and environmental performance optimization of CMCs.
The prevalence of hyperuricemia, gout, and heart failure (HF) is on the rise, and these conditions often share similar risk factors. The present study aimed to evaluate the relationship among ...hyperuricemia, gout, HF, and all-cause mortality.
The data on nonpregnant participants aged ≥ 20 years with or without hyperuricemia, gout, and HF from the National Health and Nutrition Examination Survey 2001-2018 and 2007-2018 were included in this study. The binary logistic regression, Kaplan-Meier curve, Cox proportional-hazards model, and restricted cubic spline analysis were employed to evaluate the relationship among hyperuricemia, gout, HF, and all-cause mortality.
Of 204,179,060 and 223,702,171 weighted eligible participants, 40,044,228 (19.6%) and 9,158,600 (4.1%) had hyperuricemia and gout, respectively. Older age, diabetes, stroke, and coronary artery disease were the risk factors for HF among patients with hyperuricemia and gout. The median survival time was 7.00 years and 6.25 years and the 5-year survival rate was 59.9% and 55.9% for patients with HF and hyperuricemia and those with HF and gout, respectively. Patients with hyperuricemia or gout were 2.46 and 2.35 times more likely to have HF and 1.37 and 1.45 times more likely to experience all-cause mortality compared with those who did not exhibit these conditions. The restricted cubic spline showed a nonlinear correlation between uric acid levels and HF and a J-shaped correlation between uric acid levels and all-cause mortality.
Ambulatory patients with hyperuricemia or gout were more likely to have HF compared with those without hyperuricemia or gout. Patients with HF with hyperuricemia or gout were more likely to experience all-cause mortality in the long-term follow-up.
The immunoinhibitory effect of glucocorticoid and immunoenhancing attributes of melatonin (MEL) are well known, however, the involvement of glucocorticoid receptor (GR) in melatonin modulation of ...bacterial toxins caused-inflammation has not been studied in colon. Pyocyanin (PCN), a toxin released by Pseudomonas aeruginosa, can destroy cells through generating superoxide products and inflammatory response. Here we report that PCN treatment elevated the generation of reactive oxygen species (ROS), which further lead to mitochondrial swelling and caspase cascades activation both in vivo and in vitro. However, MEL treatment alleviated the oxidative stress caused by PCN on cells through scavenging ROS and restoring the expression of antioxidant enzyme so that to effectively alleviate the apoptosis. Large amounts of ROS can activate the NLRP3 signaling pathway, so MEL inhibited PCN induced NLRP3 inflammasome activation and inflammatory cytokines (IL-1β, IL-8, and TNF-α) secretion. In order to further investigate the molecular mechanism, goblet cells were exposed to MEL and PCN in the presence of luzindole and RU486, inhibitors of MEL receptors and GR respectively. It was found that PCN significantly inhibited the expression level of GR, and MEL effectively alleviated the inhibition phenomenon. Moreover, we found that MEL mainly upregulated the expression of GR to achieve its anti-inflammatory and anti-apoptotic functions rather than through its own receptor (MT2) in colon goblet cells. Therefore, MEL can reverse the inhibitory effects of PCN on GR/p-GR expression to present its anti-oxidative and anti-apoptotic function.
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•Glucocorticoid receptors are the vital targets of bacterial toxins pyocyanin in colon.•Melatonin presented anti-apoptotic effects mainly through glucocorticoid receptors.•Glucocorticoid receptors were involved in melatonin inhibiting the activation of NLRP3 inflammasome induced by pyocyanin.
Electron-transport-layer free perovskite solar cells (ETL-free PSCs) have attracted great attention due to their low cost and simple manufacturing process. However, an additional interface layer has ...to be introduced, and the currently achieved efficiency remains far from full-structure PSCs. Here, we report an in situ interface engineering strategy by the methylammonium acetate (MAAc) ionic liquid perovskite precursor. We found that a dipole layer was in situ constructed through the physical adsorption of the residual MAAc polar molecules on the indium tin oxide electrode, which is significantly different from the treatment by the interface layer in previous reports. This allows a decrease of the effective work function and enables in situ band bending in the perovskite semiconductor. The in situ band bending facilitates charge collection and hinders interfacial charge recombination, leading to ETL-free PSCs with a maximum power conversion efficiency of 21.08%, which is the highest report to date.
We investigated the small fatigue crack behavior of alloy GH4169 by using single-edge-notch tension specimens. Residual stress introduced by machining process was taken into consideration, and two ...stress levels were selected. A comparison was made between the experimental results of specimens with and without machining-induced residual stress. The results indicated that fatigue cracks of the two types of specimens initiated from surface inclusions or grain boundaries. For both types of specimens, small cracks grew very slowly when the crack lengths were less than 500 μm. The small crack growth might decelerate and retard temporarily for the existence of grain boundaries. The residual stress effect on crack growth can be identified at σ
max
= 380 MPa, i.e., compressive residual stress might impede the crack growth. However, this phenomenon was indistinguishable at σ
max
= 410 MPa.
EEG-based emotion classification is a vital aspect of human–machine interfaces. However, inter-subject variability poses a challenge for accurate domain-agnostic EEG emotion recognition, often ...requiring individual model calibration with a robust base model for fine-tuning. To overcome this limitation and develop a generalized model, we propose a Generalized Model based on Mutual Information for EEG Emotion Recognition without Adversarial Training (MI-EEG). The MI-EEG model leverages disentanglement to extract shared features, wherein it separates EEG features into domain-invariant class-relevant features and other features. To avoid adversarial training, mutual information minimization is applied during the decoupling process. Additionally, mutual information maximization is used to enrich the features by strengthening the relationship between domain-invariant class-relevant features and emotion labels. Furthermore, the transformer-based feature extractor, which utilizes a multi-headed attention mechanism and pooling operations, enhances the feature quality in the time dimension. The experimental evaluation on two emotional EEG datasets demonstrates the superior performance of the proposed EEG-MI model compared to existing state-of-the-art methods.
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•Mutual information up bound minimization makes Fre and Fir separated.•Mutual information lower bound maximization makes Fre and Fg more relevant.•The Multi-head attention neural network makes the model more robust.
Recently, an increasing number of studies sequence multiple biopsies of primary tumors, and even paired metastatic tumors to understand heterogeneity and the evolutionary trajectory of cancer ...progression. Although several algorithms are available to infer the phylogeny, most tools rely on accurate measurements of mutation allele frequencies from deep sequencing, which is often hard to achieve for clinical samples (especially FFPE samples). In this study, we present a novel and easy-to-use method, PTI (Phylogenetic Tree Inference), which use an iterative top-down approach to infer the phylogenetic tree structure of multiple tumor biopsies from same patient using just the presence or absence of somatic mutations without their allele frequencies. Therefore PTI can be used in a wide range of cases even when allele frequency data is not available. Comparison with existing state-of-the-art methods, such as LICHeE, Treeomics, and BAMSE, shows that PTI achieves similar or slightly better performance within a short run time. Moreover, this method is generally applicable to infer phylogeny for any other data sets (such as epigenetics) with a similar zero and one feature-by-sample matrix.
As the 6G network is evolving towards a space-air-ground integrated scale with ubiquitous long-distance non-terrestrial network (NTN) links, packet-level streaming forward erasure correction (FEC), ...which can achieve low end-to-end in-order delivery delay over lossy links with long propagation delay, has drawn increasing interest. However, the existing streaming FEC has a problem that full-length encoding windows (EWs) including all non-acknowledged source packets are used when generating repair packets, which incurs high computational cost when the link's bandwidth-delay product is large. To address the problem, this paper proposes a new low-complexity streaming FEC design, where a mixture of short and full-length EWs are used. We propose a novel method to analyze the decoding window width observed by arriving repair packets, which is based on the analysis of the busy period of a virtual queue using renewal theory. Later, using the analysis as the key enabler, a design problem is formulated and solved to optimize parameters including the EW width and the fraction of short-length repair packets such that the computational cost is reduced. Evaluations using real-life code implementations show that the proposed design can significantly reduce the computational cost, while maintaining the key benefits of the original streaming FEC.
AZ91–(1–3wt%) Ca alloys were prepared by direct squeeze casting, in which the melt was solidified under applied pressure. The effects of processing parameters (such as applied pressure and pouring ...temperature) and Ca content on microstructure and mechanical properties of squeeze casting AZ91–Ca alloys were investigated. The results indicate that the microstructure was refined with the increase of applied pressure, and the mechanical properties were improved. When the pouring temperature was lowered down to near the liquidus, the microstructure was further refined and α-Mg grains turned rosette-like. The negative effect on ambient temperature mechanical properties caused by the addition of Ca into AZ91 alloy was inhibited by squeeze casting. Compared to conventional casting, squeeze casting process can offer AZ91–Ca alloys better mechanical properties, especially in elongation to failure (Ef).
A new model for predicting the creep behavior of SiC/PyC/SiC mini-composites under wet oxygen atmosphere (900 ~ 1200℃, 1% ~ 50%H
2
O) is developed based on the thermal–mechanical, ...environmental-micro, fiber strength degradation, and creep-oxidation model. The model firstly takes the effects of the catalysis of water vapor, the oxidation of matrix and interphase, fiber strength degradation due to the grain growing, thermal decomposition, and growth of silica scale, creep of fibers into account comprehensively. The predicted strain–time curves involving three stages presented for the case of a KD-I/PyC/SiC mini-composites are compared to the experimental data at 900℃ under 1%H
2
O. The model predictions show that the increase of temperature accelerates the consumption of interphase and the growth of silica scale on the fiber, which promotes the failure of fibers by load transfer and fiber degradation. The increase of water vapor pressures promotes the growth of silica scale on the fiber and matrix, but has little influence on the consumption of interphase due to the effect of inhibition of water vapor on the carbon. The effect of creep and oxidation on the matrix crack spacing is checked by the critical matrix strain energy criterion and the results indicate that the creep and oxidation of the mini-composites have no influence on the matrix crack spacing. The application of the method in this work contributes to the analysis of mechanical behavior and failure mechanism of SiC
f
/SiC structures, such as turbine guide vane, which may serve in the wet oxygen atmosphere for a long period.
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