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As the simulation data of the Simufact Additive software was inconvenient to process, QT and structured query language (MySQL) database were used to develop the database to solve the processing of the simulation data. The GUI interface that has the functions of processing and saving the simulation data was designed. The interface developed by QT was used to start the Simufact Additive software, connect to the MySQL database and save the simulation data. The results showed that using MySQL as the management of simulation data has achieved better results in the post-processing of simulation data.

Developing fabrics with enhanced thermal protection is a cutting-edge topic in area of thermal protective clothing (TPC) for workers under heat hazards. Here, temperature-responsive NiTi shape memory alloy (SMA) filaments, which transform into a sinusoid form under a stimulus of temperature exceeding their austenite start temperature of 45.1 °C, were prepared. Nine composite fabrics (CFs) using SMA filaments and aramid yarns, different in filament interval, air gap orientation, aramid yarn type and fabric density, were fabricated and incorporated into traditional three-layer TPC fabric system, resulting in a four-layer smart fabric system (SFS) with adaptive structure. Thermal protective performance (TPP) tests demonstrated the addition of CF could significantly slow down the rise of temperature at skin surface and prolong the time to the first-degree burn. With the decrease of filament interval or increase of fabric density, TPP of SFS was improved due to more heat accumulation within and less heat conduction through the fabric. This study would inspire engineering CFs with enhanced TPP, thus pushing forward the development of smart technology in textile engineering. [ABSTRACT FROM AUTHOR]

Wearing a liquid cooling garment (LCG) that offers near-zone cooling improves the thermal comfort of pilots working in hot environments. Four LCG samples with different arrangements of tubes for distributing liquid were developed. Based on the analysis of the overall and local cooling efficiency of the four LCG samples using manikin tests, another novel LCG with a horizontal-vertical combined tube was proposed to achieve optimal cooling performance. Human trials were conducted to check the novel LCG for improving the thermal comfort of pilots in a hot indoor environment (40°C, 40% RH). The mean skin temperature of the subjects wearing the novel LCG was reduced by 1.9°C in the 120-minute-duration flying simulation work compared to the no-cooling scenario, and the greatest decrease in skin temperature (i.e., 5.7°C) was exhibited at the back waist. The thermal sensation at the upper body was improved to nearly neutral, and the heat stress level was reduced from moderate to slightly. The findings provide a guideline for designing personal LCG, thus benefiting the comfort and safety of pilots in hot cockpits. [ABSTRACT FROM AUTHOR]

High-fat exposure leads to impaired intestinal barrier function by disrupting the function of intestinal stem cells (ISCs); however, the exact mechanism of this phenomenon is still not known. We hypothesize that high concentrations of deoxycholic acid (DCA) in response to a high-fat diet (HFD) affect aryl hydrocarbon receptor (AHR) signalling in ISCs and the intestinal barrier. For this purpose, C57BL/6J mice feeding on a low-fat diet (LFD), an HFD, an HFD with the bile acid binder cholestyramine, and a LFD with the DCA were studied. We found that high-fat feeding induced an increase in faecal DCA concentrations. An HFD or DCA diet disrupted the differentiation function of ISCs by downregulating AHR signalling, which resulted in decreased goblet cells (GCs) and MUC2, and these changes were reversed by cholestyramine. In vitro experiments showed that DCA downregulated the differentiation function of ISCs, which was reversed by the AHR agonist 6-formylindolo [3,2-b]carbazole (FICZ). Mechanistically, DCA caused a reduction in indoleamine 2,3-dioxygenase 1 (IDO1) in Paneth cells, resulting in paracrine deficiency of the AHR ligand kynurenine in crypts. We demonstrated for the first time that DCA disrupts intestinal mucosal barrier function by interfering with AHR signalling in ISCs. Supplementation with AHR ligands may be a new therapeutic target for HFD-related impaired intestinal barrier function. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors with a poor prognosis. Recently, necroptosis has been reported to participate in the progression of multiple tumors. However, few studies have revealed the relationship between necroptosis and PDAC, and the role of necroptosis in PDAC has not yet been clarified. Methods: The mRNA expression data and corresponding clinical information of PDAC patients were downloaded from the TCGA and GEO databases. The necroptosis-related genes (NRGs) were obtained from the CUSABIO website. Consensus clustering was performed to divide PDAC patients into two clusters. Univariate and LASSO Cox regression analyses were applied to screen the NRGs related to prognosis to construct the prognostic model. The predictive value of the prognostic model was evaluated by Kaplan-Meier survival analysis and ROC curve. Univariate and multivariate Cox regression analyses were used to evaluate whether the risk score could be used as an independent predictor of PDAC prognosis. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and single-sample gene set enrichment analysis (ssGSEA) were used for functional enrichment analysis. Finally, using qRT-PCR examined NRGs mRNA expression in vitro. Results: Based on the TCGA database, a total of 22 differential expressed NRGs were identified, among which eight NRGs (CAPN2, CHMP4C, PLA2G4F, PYGB, BCL2, JAK3, PLA2G4C and STAT4) that may be related to prognosis were screened by univariate Cox regression analysis. And CAPN2, CHMP4C, PLA2G4C and STAT4 were further selected to construct the prognostic model. Kaplan-Meier survival analysis and ROC curve showed that there was a significant correlation between the risk model and prognosis. Univariate and multivariate Cox regression analyses showed that the risk score of the prognostic model could be used as an independent predictor. The model efficacy was further demonstrated in the GEO cohort. Functional analysis revealed that there were significant differences in immune status between high and low-risk groups. Finally, the qRT-PCR results revealed a similar dysregulation of NRGs in PDAC cell lines. Conclusion: This study successfully constructed and verified a prognostic model based on NRGs, which has a good predictive value for the prognosis of PDAC patients. [ABSTRACT FROM AUTHOR]

Long-term high-fat diet (HFD) destroys the intestinal mucosal barrier by damaging intestinal stem cells (ISCs). A HFD can increase the concentration of intestinal deoxycholic acid (DCA) and decrease the secretion of interleukin-22 (IL-22), which plays an important role in the proliferation, repair and regeneration of ISCs. We hypothesized that increased level of intestinal DCA induced by a HFD leads to ISC dysfunction by reducing the IL-22 levels in intestinal tissues. In this study, 2 weeks of a DCA diet or a HFD damaged ileal ISC and its proliferation and differentiation, resulting in a decrease in Paneth cells and goblet cells. Importantly, 2 weeks of a DCA diet or a HFD also reduced ileal IL-22 concentration, accompanied by a decreased number of group 3 innate lymphoid cells in ileal mucosa, which produce IL-22 after intestinal injury. Concurrent feeding with bile acid binder cholestyramine prevented all these changes induced by a HFD. In addition, in vitro study further confirmed that exogenous IL-22 reversed the decline in the proliferation and differentiation of ileal ISCs induced by DCA stimulation. Collectively, these results revealed that the decrease in intestinal IL-22 induced by DCA may be a novel mechanism by which HFD damages ISCs. The administration of IL-22 or a bile acid binder may provide novel therapeutic targets for the metabolic syndrome caused by a HFD. [Display omitted] • Deoxycholic acid (DCA) elevated by high-fat feeding impaired the intestinal stem cells (ISCs). • DCA damaged group 3 innate lymphoid cells and reduced the IL-22 level in the ileum. • A bile acid binder cholestyramine restored the IL-22 levels and the functions of ISCs. • Exogenous IL-22 reversed DCA induced damage of ISC function. [ABSTRACT FROM AUTHOR]

Various acoustic and mechanical wave components have been developed. Most of them focused on the control of energy flow. However, these waves are not only energy flow but also wave signals with a frequency dependence. In this Letter, we propose a mechanical wave switch (MWS) capable of controlling energy flow and output frequency simultaneously. It consists of a difference frequency generation (DFG) unit and a wave filter. The DFG unit consists of two mass blocks and a tension/compression asymmetrical bilinear spring, and the wave filter is a one-dimensional mass-spring lattice. Systematical calculations were carried out to identify the critical condition for the design of MWSs. Both numerical and experimental results demonstrate the capability of the proposed MWS to tune the energy flow and the output frequency of acoustic waves via a small amplitude control wave signal. The scale-independent MWS can be implemented at micro- and nanoscales. [ABSTRACT FROM AUTHOR]

To understand the effectiveness of some garment adjustment designs for high school uniform in winter, manikin tests and subjective wear trials were carried out. Five series of school uniform ensembles were involved in the experiments. They were further collocated into 17 ensemble configurations with detachable designs (ensembles A and B) and opening structures (ensembles C, D, and E). As manikin test results showed, the thermal insulation of ensembles A, B and C varied most significantly due to their adjustment design. The possible thermal insulation regulation levels were approximately 68% and 80% for ensembles A and B, and 60% and 90% for ensemble C. Two human trials that simulated students' daily movements between indoor and outdoor classes were conducted with ensemble A. Two climate chambers were used at the same time for indoor and outdoor environment simulation. In Case X, where ensemble A was assumed to be non-detachable, skin temperatures that were 0.6℃ lower were finally observed compared to Case Y, where ensemble A was detachable. Moreover, significantly (p < 0.1) better thermal comfort and thermal sensation evaluations were given during low-intensity activities in Case Y, especially for the torso segments. The detachable high school uniform design was finally proved to be efficient in improving human thermal comfort under various class environments. It was also concluded that more protective measures should be adopted for the hands and face in the school uniform design process. [ABSTRACT FROM AUTHOR]

Triggering receptor expressed on myeloid cells 2 (TREM2) is an important member of the immunoglobulin family of inflammatory stimulating receptors and is involved in a number of pathophysiological processes. The present study aimed to investigate the role of TREM2 in neurotoxicity induced by high cholesterol levels in SH-SY5Y cells and explore the potential mechanism. SH-SY5Y cells were routinely cultured and stimulated with a range of cholesterol concentrations. Cell viability was assessed using an MTT assay, morphological changes were observed, and the cell cycle distribution was measured using flow cytometry. Lipid deposition was measured by Oil red O staining, and the mRNA and protein expression levels of SRBEP-1 and SRBEP-2 were detected by quantitative PCR and western blotting, respectively. Moreover, the protein expression levels of BDNF, Copine-6, TREM1, TREM2, and key molecules of the Wnt signaling pathways were detected by western blotting. Finally, TREM2 was overexpressed to investigate its potential role in high cholesterol-induced neurotoxicity. The results showed that cell viability was significantly decreased in SH-SY5Y cells stimulated with cholesterol (0.1~100 µM) in a dose- and time-dependent manner. Stimulation with 100 µM cholesterol for 24 h resulted in morphological injuries, increased the proportion of SH-SY5Y cells at G0/G1, the degree of lipid accumulation, and the protein expression levels of sterol regulatory element binding protein (SREBP)1 and SREBP2, markedly decreased the protein expression levels of BDNF, Copine-6, and TREM2, and the p-β-catenin/β-catenin ratio, and increased the expression levels of nesfatin-1, TREM1 and the p-GSK3β/GSK3β ratio. Furthermore, the imbalanced expression of BDNF, Copine-6, nesfatin-1, and p-GSK3β induced by high cholesterol levels was reversed after overexpression of TREM2. These results suggest that a high concentration of cholesterol could induce cell injury and lipid deposition in SH-SY5Y cells and that the underlying mechanism may be associated with imbalanced TREM2 expression. [ABSTRACT FROM AUTHOR]

Sugarcane is an economically important crop whose growth and carbon uptake play vital roles in the carbon cycle, food security, and global trade development. However, the response of the carbon uptake of sugarcane to climate variations and the influencing factors are still unclear. In this study, seven sugarcane plantation distribution maps during 2000 and 2018 in Guangxi, China, were generated using time series Landsat and Sentinel-2 imagery, and these maps were used to produce stable sugarcane sites by identifying pixels without land cover transformation. Time series gross primary production (GPP) and climate datasets were used to analyze the response of annual GPP to temperature, precipitation, and their interacting effects under different landforms (rugged ground and flat ground) and growing periods. The results showed a significantly positive correlation between annual GPP change and temperature variations. Extreme precipitation, including extreme drought and extreme wetness, caused the annual GPP to decrease sharply, except for extreme wetness in the early growing period. The decrease in annual GPP mainly appeared when extreme drought and hot conditions or extreme wet and cold conditions coexisted, ranging from −20.37% to −0.23%, while the increase in annual GPP especially appeared when non-extreme precipitation and high temperature co-occurred, ranging from 0.02% to 8.44%. In addition, the responses of sugarcane annual GPP change to extreme temperature and precipitation were significantly different between rugged and flat ground. Overall, this study indicated that spatiotemporal heterogeneities existed in the response of sugarcane carbon uptake to climate variations. In the future, effective measures should be adopted in sugarcane management and cultivation to reduce the negative effects of climate change on crop production. • Sugarcane's carbon uptake response discrepantly to heat and water stresses. • Impacts of climate variations on sugarcane GPP varied with growing stages. • Rugged grounds change the response of sugarcane GPP to extreme climates. [ABSTRACT FROM AUTHOR]

• Acoustic emission technique is used to monitor the fatigue process of asphalt mixtures. • The evolutionary feature of fatigue damage could be characterized by AE energy and RA-AF. • Different damage behaviors are identified by time and frequency characteristics of AE events. • A new AE index is proposed for assessing the damage state. Fatigue cracking of asphalt materials directly affects the performance and safety of asphalt pavements. It is necessary to identify the materials condition with acoustic emission (AE) as the real time monitoring technique. The objective of this study was to diagnose the damage behavior of asphalt mixtures from the time and frequency characteristics of AE signals. Firstly, the semi-circular bending (SCB) fatigue test and AE detection were conducted to explore the AE response of asphalt mixtures subjected to cyclic loads. Then, the Fast Fourier Transform (FFT) and Continuous Wavelet Transform (CWT) were applied to discuss the dominant frequency characteristics and time–frequency distribution of AE waveforms. Finally, an index (R BD), defined as the ratio of fractal dimension of AE waveforms decomposed by the Discrete Wavelet Transform (DWT), was proposed to evaluate the damage state of asphalt mixtures. The results show that AE energy rate exhibits distinct variation signatures at different damage stages. The average frequency (AF) and rise angle (RA) of AE signals reveal that the coupling effect of tensile and shear cracks promotes the deterioration of asphalt mixtures. Most of the dominant frequencies of AE events generated from cracks are concentrated within the range of 13 to 30 kHz. The discrepancies in the time–frequency distribution of AE events could effectively discriminate the types of damage sources. The proposed index R BD is sensitive to the change of damage state of asphalt mixtures, producing corresponding reductions. [ABSTRACT FROM AUTHOR]

Carbon nanofibers were in-situ synthesized on porous carbon composites via a simple and economic technique of oxyacetylene torch ablation without catalyst assistance. The resultant nanofibers with good crystallinity in the (002) plane were polycrystalline graphite, which grew in the ablation center region. They were generally tens of nanometers in diameter, several microns in length, and grew at different orientations, exhibiting flower-like nanofiber clusters covered with amorphous carbon film. The formation mechanism may be governed by exfoliation of graphite layers, or attachment of graphitic carbon atoms to silicon monoxide for growth during the cooling process. [ABSTRACT FROM PUBLISHER]

The fractures in asphalt materials evolving from microcracks directly affect the performance of asphalt pavements. Acoustic Emission (AE) technique plays a crucial role in dynamically monitoring the internal structural changes of stressed materials. This study attempted to characterize the fracture mechanism of asphalt mixtures by identifying the characteristics of recoded AE data. Firstly, the three-point bending tests and AE tests were simultaneously conducted to investigate the damage evolution process of asphalt mixtures through the time characteristics of AE parameters. Secondly, the cusp catastrophe model based on AE energy rate was employed to explore the mutational characteristics of AE process and to evaluate the damage state of asphalt mixtures. Finally, the k-means method was applied to distinguish the patterns of AE signals associating with the specific damage behaviors of asphalt mixtures during the flexural failure process. The results show that abrupt change of AE energy rate and cumulative AE energy could reflect the evolutionary characteristics of damage in asphalt mixtures. The mutational analysis of AE energy rate reveals that the damage state of asphalt mixtures subjected to the continuous external forces would change between instability and stability, which could be served as a complementary approach for further understanding the periodic variation characteristics of damage evolution process based on cumulative AE energy. The k-means method could effectively classify the recorded AE signals of asphalt mixtures in three-point bending tests into three distinctive clusters. The potential mechanisms for the clustered signals corresponding to different damage behaviors of asphalt mixtures could be characterized by the parametric characteristics and the wavelet power spectrum of AE signals. [ABSTRACT FROM AUTHOR]

Long-term high-fat feeding (HF) induces intestinal mucosal barrier damage. However, the mechanism for this remains unclear. HF can elevate the intestinal and circulating bile acid (BA) levels, especially deoxycholic acid (DCA). We hypothesize that BAs elevated by HF regulate intestinal stem cell (ISC) function, which may contribute to mucosal barrier injury in the ileum of mice. In this study, we showed that 2 weeks of HF resulted in a shortening of intestinal villi and a decrease in the tight junction (TJ) protein occludin in the ileum of mice, accompanied by an increase in circulating BA levels. Importantly, 2 weeks of HF also reduced ileal ISCs and goblet cells and decreased the proliferation function of ISCs and their ability to differentiate into goblet cells. Endoplasmic reticulum (ER) stress was found to be involved in the process of ISC damage. All these alterations were reversed by cofeeding with the bile acid binder cholestyramine. In addition, the in vitro studies also confirmed a cytotoxic effect of DCA at a high concentration on ISCs and goblet cells. In conclusion, these data suggested that high levels of BAs induced by HF could impair ISC function by triggering ER stress, resulting in the disruption of the intestinal mucosal barrier. • High-fat feeding (HF) increases bile acids (BAs) and damages the intestinal mucosa. • HF reduces the number of small intestinal stem cells (ISCs) and decreases the differentiation of goblet cells from ISCs. • HF increases endoplasmic reticulum (ER) stress in the intestinal mucosa and ISCs. • BAs elevated by HF induce ER stress in ISCs and contribute to mucosal barrier damage in the ileum. [ABSTRACT FROM AUTHOR]

Spasmolytic polypeptide-expressing metaplasia (SPEM) is an important risk factor for the occurrence of gastric cancer. It may be driven by a chronic inflammatory environment in which macrophage is involved. Studies have shown that intestinal metaplasia may originate from SPEM, and bile acid-induced chronic inflammation plays an important role in the process of intestinal metaplasia. However, whether bile acids are involved in the development of SPEM and the specific mechanism are unclear. Meanwhile, macrophages are known to be involved in inflammation regulation by releasing various factors, including exosomes. In this study, we hypothesized that the exosomes released from macrophages stimulated by deoxycholic acid participated in the development of SPME. In vivo, mice were gavaged with deoxycholic acid for 4 weeks, and gastric tissues were harvested. In vitro, deoxycholic acid-induced macrophage-derived exosomes were isolated by ultracentrifugation and cocultured with the gastric organoids of mice. Immunofluorescence staining and quantitative real-time PCR were used to analyze markers of macrophages and SPEM. In vivo, after 4 weeks of deoxycholic acid intragastric administration, macrophage markers (F4/80) and SPEM markers (TFF2 and GSII lectin) were increased in from treated mice compared with those from normal control mice. In vitro, macrophage-derived exosomes labeled with PKH67 were internalized by gastric organoids. Deoxycholic acid-induced macrophage-derived exosomes increased the expression of SPEM markers (TFF2 and GSII lectin) in gastric organoids compared to exosomes derived from macrophages without deoxycholic acid stimulation. Macrophage-derived exosomes may be a novel mechanism by which deoxycholic acid promotes SPEM. • Deoxycholic acid promoted the development of spasmolytic polypeptide-expressing metaplasia in the stomach of mouse. • Macrophage-derived exosomes were internalized by gastric organoid from mouse. • Exosomes promoted the development of spasmolytic polypeptide-expressing metaplasia in gastric organoids. [ABSTRACT FROM AUTHOR]

Cholesterol overloading and bile acid metabolic disorders play an important role in the onset of cholesterol gallstone (CGS). Short-chain fatty acids (SCFAs) can regulate bile acid metabolism by modulating the gut microbiota. However, the role and mechanism by which sodium butyrate (NaB) targets bile acids to attenuate CGS are still unknown. In this study, continuous administration of 12 mg/day for 8 weeks was decreased the incidence of gallstones induced by lithogenic diet (LD) from 100% to 25%. NaB modulated SCFAs and improved the gut microbiota. The remodeling of the gut microbiota changed the bile acid compositions and decreased cecal tauro-α-muricholic acid (T-α-MCA) and tauro-β-muricholic acid (T-β-MCA) which are effective farnesoid X receptor (FXR) antagonists. The quantitative real-time PCR examination showed that NaB significantly increased levels of ileal Fxr, fibroblast growth factor-15 (Fgf-15) and small heterodimer partner (Shp) mRNA and subsequently inhibited bile acid synthesis. In addition, NaB enhanced bile acid excretion by increasing the levels of hepatic multidrug resistance protein 2 (Mdr2) and bile salt export pump (Bsep) mRNA, and it enhanced bile acid reabsorption in the intestine by increasing the levels of ileal bile acid transporter (Ibat) mRNA. In addition, NaB reduced the absorption of cholesterol in the intestine and inhibited the excretion of cholesterol in the liver, which reduced the cholesterol concentration in serum and bile. Furthermore, the protective effects of NaB administration were abolished by FXR antagonists. Taken together, our results suggest that NaB mitigates CGS by modulating the gut microbiota to regulate the FXR-FGF-15/SHP signaling pathway. [ABSTRACT FROM AUTHOR]

The crosstalk between macrophages and gastric epithelial cells has emerged as a player in chronic inflammation during intestinal metaplasia. However, the role of bile acid on this modulation remains to be studied. We hypothesized that deoxycholic acid-induced macrophages secreted exosomes to mediate intercellular communication and promoted intestinal metaplasia in human gastric epithelial cells (GES-1 cells). Macrophage-derived exosomes (M-Exos) and deoxycholic acid-induced macrophage-derived exosomes (D-Exos) were isolated by ultracentrifugation. EdU staining and CCK-8 assay were utilized to evaluate the effects of exosomes on the proliferation of GES-1 cells. Intestinal metaplasia was assessed by the expression of caudal-related homeobox transcription factor 2 (CDX2) at both mRNA and protein level. MicroRNA sequencing revealed the microRNA (miRNA) expression profiles of M-Exos and D-Exos. The role of a specific miRNA and mRNA was analyzed by using miRNA mimics, miRNA inhibitors and siRNAs. D-Exos promoted the expression of CDX2 and suppressed the proliferation of GES-1 cells, compared to M-Exos. The miRNA profiles and quantitative real-time PCR examination showed D-Exos enriched a higher level of hsa-miR-30a-5p than M-Exos. Overexpressed has-miR-30a-5p increased CDX2 expression and inhibited the proliferation in GES-1 cells via targeted Forkhead Box D1 (FOXD1), a potential regulatory factor in the process of intestinal metaplasia. D-Exos may promote intestinal metaplasia and suppress proliferation of GES-1 cells via hsa-miR-30a-5p targeting FOXD1, which may be involved in the action mechanism of bile acid on gastric mucosa. [ABSTRACT FROM AUTHOR]