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The scientific field concerned with the study of regeneration has developed rapidly in recent years. Stem cell therapy is a highly promising therapeutic modality for repairing tissue defects; however, several limitations exist, such as cytotoxicity, potential immune rejection, and ethical issues. Exosomes secreted by stem cells are cell‐specific secreted vesicles that play a regulatory role in many biological functions in the human body; they not only have a series of functional roles of stem cells and exert the expected therapeutic effects, but they can also overcome the mass limitations of stem cells and are thus considered in the research as an alternative treatment strategy for stem cells. Since dental stem cell‐derived exosomes (DSC‐Exos) are easy to acquire and present modulating effects in several fields, including neurovascular regeneration and craniofacial soft and hard tissue regeneration processes, they are served as an emerging cell‐free therapeutic strategy in various systematic diseases. There is a growing body of research on various types of DSC‐Exos; however, they lack systematic elaboration and tabular summarization. Therefore, this review presents the isolation, characterization, and phenotypes of DSC‐Exos and focuses on their current status of functions and mechanisms, as well as the multiple challenges prior to clinical applications. [ABSTRACT FROM AUTHOR]

Background: Spexin is a novel peptide hormone and has shown antinociceptive effects in experimental mice. This study is aimed at evaluating the association of serum spexin level with diabetic peripheral neuropathy (DPN) and related pain in a Chinese population. Methods: We enrolled 167 type 2 diabetes mellitus (T2DM) including 56 patients without DPN (non-DPN), 67 painless DPN, and 44 painful DPN. Serum spexin was measured using ELISA. Logistic regression models were performed to analyze the independent effects of spexin on prevalence of DPN and painful DPN. In streptozotocin (STZ)-induced diabetic mice, mechanical pain threshold was measured using electronic von Frey aesthesiometer. Human peripheral blood mononuclear cells (PBMCs) were isolated and further stimulated with lipopolysaccharide without or with spexin. The gene expression was assayed by qPCR. Results: Compared with non-DPN, serum spexin level decreased in painless DPN and further decreased in painful DPN. The odds of DPN was associated with low spexin level in T2DM, which was similar by age, sex, BMI, and diabetes duration, but attenuated in smokers. The odds of having pain was associated with decreased spexin level in DPN, which was similar by age, sex, smoking status, and diabetes duration, but attenuated in normal weight. Furthermore, we observed that mechanical pain threshold increased in spexin-treated diabetic mice. We also found that lipopolysaccharide treatment increased the mRNA level of TNF-α, IL-6, and MCP-1 in human PBMCs, while spexin treatment prevented this increase. Conclusions: These results suggested that spexin might serve as a protective factor for diabetes against neuropathology and pain-related pathogenesis. [ABSTRACT FROM AUTHOR]

Driving behavior analysis plays an important role in improving the human-like driving capability of the Advanced Driver Assistance System (ADAS) and autonomous driving technologies. In this study, 906 data of drivers stopping normally at urban intersections were extracted from natural driving data to study reaction characteristics and braking characteristics of drivers in real road traffic. The effects of traffic state and traffic density on approach speed and reaction distance were studied using one-way ANOVA, and the relationships between maximum deceleration, average deceleration, braking duration, and influencing factors were analyzed using hierarchical multiple regression. The main results indicate the following: (1) compare with free driving, the approach speed in the following state was lower, and following traffic also caused drivers with higher speeds to further increase reaction distance in high-density traffic. (2) Traffic density only affected the approach speed in the free-driving condition. High-density traffic caused drivers to reduce speed. (3) There was a clear correlation between approach speed and reaction distance: the greater the approach speed, the longer the reaction distance. (4) The braking characteristics were mainly affected by the self-vehicle motion state. Drivers braked to a stop with greater average deceleration and maximum deceleration in a shorter time when the approach speed was higher or the reaction distance was shorter. (5) Both traffic state and traffic density had an influence on the braking characteristics. Drivers reduced average deceleration and increased braking duration in the following state and high-density traffic. (6) When following a preceding vehicle to stop, the braking characteristics of drivers were no longer influenced by the traffic density but were related to the relative motion state with the preceding vehicle. In addition to the driving behavior analysis, the identification method of traffic participants and ranging method used in this study will also advance the development of autonomous driving technologies and driver assistance systems., Author(s): Tian Yuan (corresponding author) [1]; Rui Liu (corresponding author) [1]; Xuan Zhao [1]; Qiang Yu [1]; Xichan Zhu [2]; Shu Wang [1] 1. Introduction Advanced Driver Assistance System and [...]

Purpose. To examine the mediating role of positive psychological capital in the relationship between nursing students' perceived social support and bullying behavior in nursing education. Design and Methods. In May 2021, a sample of 1196 nursing students majoring in nursing at a medical college was conveniently selected as the study population. A set of questionnaires, including a General Information Questionnaire, Perceived Social Support Scale (PSSS), Positive Psychological Capital Questionnaire (PPQ), and Bullying Behaviors in Nursing Education Scale (BBNE), were utilized to examine and analyze the relationships among the variables. Findings. The scores of nursing students' PSSS, PPQ, and BBNE were 68.19 ± 11.90, 123.97 ± 18.74, and 13.31 ± 9.24, respectively. There was a negative correlation (r = −0.421, P < 0.01) between perceived social support and bullying behaviors in nursing education among nursing students. Positive psychological capital partially mediated the relationship between perceived social support and bullying behaviors in nursing education, accounting for 19.88% of the total effect. Further analysis revealed that self-efficacy, resilience, optimism, and hope in positive psychological capital each played a partial mediating role in the impact of nursing students' perceived social support on bullying behaviors in nursing education, with the ratio of indirect effect to total effect being 5.38%, 7.74%, 6.09%, and 5.34%, respectively. Practice Implications. The impact of perceived social support on bullying behaviors in nursing education is substantial among nursing students, and it can indirectly influence bullying behaviors through positive psychological capital. Nursing educators should pay attention to nursing students with lower levels of social support, and they can decrease the occurrence of bullying behaviors by enhancing social support and fostering higher levels of psychological capital. [ABSTRACT FROM AUTHOR]

Rosmarinic acid (RA) is a natural phenolic compound extracted from the Labiatae family and is a natural antioxidant. In this study, walnut oil added with RA was treated with different ultraviolet radiations, and stabilization effects in terms of the same conditions (0.2 mg/g) were compared with synthetic antioxidant (BHT). In order to compare the effectiveness of three UV treatments, different lab tests were conducted, namely, the acid value, peroxide value, iodine value, anisidine value, DPPH free radical scavenging rate, and malondialdehyde content. The enhanced UV-A, UV-B, and UV-C radiation intensities have increased the oxidation stability of RA-added walnut oil, of which UV-B has the greatest influence on the oxidative stability of walnut oil. When both RA and BHT were added at 0.2 mg/g, the antioxidant effect of RA is superior to the general antioxidant BHT. [ABSTRACT FROM AUTHOR]

Background/Aims. The underlying mechanisms of differential responsiveness to IFN remain poorly understood. The elongation factor Tu GTP binding domain-containing protein 2 (EFTUD2), involved in RNA splicing and pre-mRNA processing, was recognized as a novel innate immune regulator of the IFN antihepatitis C virus (HCV) effect. The aim of this study is to elucidate the mechanisms underlying EFTUD2's involvement in IFN-mediated anti-HBV responses. Methods. Using a CRISPR/Cas9 gene-editing system, EFTUD2 single allele knockout HepG2.2.15 cells were constructed. Subsequently, the HBV biomarkers in EFTUD2+/– HepG2.2.15 cells and wild-type (WT) cells with or without IFN-α treatment were detected. And the EFTUD2-regulated genes were then identified using mRNA sequence. Selected gene mRNA variants and their proteins were examined by qRT-PCR and Western blotting. To confirm the effects of EFTUD2 on HBV replication and IFN-stimulated gene (ISG) expression, a rescue experiment in EFTUD2+/– HepG2.2.15 cells was performed by EFTUD2 overexpression. Results. IFN-induced anti-HBV activity was found to be restricted in EFTUD2+/– HepG2.2.15 cells. The mRNA sequence showed that EFTUD2 could regulate classical IFN and virus response genes. Mechanistically, EFTUD2 single allele knockout decreased the expression of ISG-encoded proteins, comprising Mx1, OAS1, and PKR (EIF2AK2), through mediated gene splicing. However, EFTUD2 did not affect the expression of Jak-STAT pathway genes. Furthermore, EFTUD2 overexpression could restore the attenuation of IFN anti-HBV activity and the reduction of ISG resulting from EFTUD2 single allele knockout. Conclusion. EFTUD2, the spliceosome factor, is not IFN-inducible but is an IFN effector gene. EFTUD2 mediates IFN anti-HBV effect through regulation of gene splicing for certain ISGs, including Mx1, OAS1, and PKR. EFTUD2 does not affect IFN receptors or canonical signal transduction components. Therefore, it can be concluded that EFTUD2 regulates ISGs using a novel, nonclassical mechanism. [ABSTRACT FROM AUTHOR]

Green synthesis and metal oxide composites have attracted much attention from researchers of industry and academia. As a typical application of green synthesis and metal oxide composites, the continuous change of industrial technology and the continuous improvement of the social and economic level, the demand for oil and gas are also increasing. However, the spatial gap between the place of origin and the place of demand for oil and gas resources is large, so the long-distance oil and gas pipeline came into being. However, under the action of time, coupled with the corrosion effect of the soil due to deep burial, some pipelines have serious aging and corrosion phenomena. Therefore, in order to give corresponding guarantees for economic development, we need to conduct in-depth research and analysis of the corrosion of oil and gas long-distance pipelines and give effective solutions. In this paper, the corrosion rate prediction of buried oil and gas pipelines is studied in Changqing gas field. By improving the inertial weights and learning factors of the traditional particle swarm algorithm, the parameters of the generalized regression neural network are optimized and selected, and the corrosion rate prediction model of buried pipelines is finally constructed. Comparative analysis with other swarm intelligence algorithms shows that the improved particle swarm algorithm has stronger convergence ability and higher prediction accuracy than the BP model and SVM model. In addition, based on the detection data collected at the site of the gathering and transportation pipeline in Changqing gas field, this paper uses the extreme value distribution theory and the local corrosion progress formula to establish a prediction model for the residual life of corrosion of buried pipelines. The model established in this paper can effectively determine the risk pipe segment of buried pipeline and provide a decision-making basis for pipeline management departments. The work provides an important application guidance to green synthesis and metal oxide composites. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the association between neutrophil levels and all-cause mortality in geriatric hip fractures. Methods. Elderly patients with hip fractures were screened between January 2015 and September 2019. Demographic and clinical characteristics of the patients were collected. Linear and nonlinear multivariate Cox regression models were used to identify the association between neutrophil levels and mortality. Analyses were performed using Empower Stats and R software. Results. A total of 2,589 patients were included in this study. The mean follow-up period was 38.95 months. During the study period, 875 (33.80%) patients died due to various causes. Linear multivariate Cox regression models showed that neutrophil levels were associated with mortality after adjusting for confounding factors, when neutrophil concentration increased by 1 ∗ 10 9 / L , the mortality risk increased by 3% (HR = 1.03, 95% CI: 1.00–1.06, and P = 0210). Neutrophil concentration was used as a categorical variable; we only found statistically significant differences when neutrophil levels were high (HR = 1.27, 95% CI:1.05–1.52, and P = 0.0122). In addition, the results are stable in P for trend and propensity score matching sensitivity analysis. Conclusions. Neutrophil levels are associated with mortality in geriatric hip fractures and could be considered a predictor of death risk in the long-term. This study is registered with the Chinese Clinical Trial Registry (ChiCTR) as number ChiCTR2200057323. [ABSTRACT FROM AUTHOR]

The formation of columbite-group mineral phases in peraluminous granite has not been demonstrated to date. Here, a nanoscale study of the columbite-tantalite mineral in the Zhaojinggou Nb-Ta deposit in North China Craton elucidated its formation mechanism and the role of fluids in Nb-Ta mineralization. Transmission electron microscopy (TEM) analysis of a focused ion beam cut of the columbite-tantalite mineral revealed a comparatively well-ordered mineral structure. Energy-dispersive X-ray spectroscopy (EDS) revealed the presence of Nb, Ta, Mn, W, Fe, Sn, and Pb in the columbite-tantalite mineral. Furthermore, detailed TEM images depicted the nanoscale hydrothermal fluid occurring within the columbite-group mineral grain as well as between columbite-tantalite mineral and quartz grains. K, Al, Si, and O were found to be enriched in the hydrothermal fluid that was present between the quartz grains and the columbite-tantalite mineral. It did not react with the mineral grains of the columbite group. The ultrastructure of the columbite-tantalite mineral suggested the columbite-group mineral in the Zhaojinggou Nb-Ta deposit formed during magmatic crystallization rather than from hydrothermal fluids. Furthermore, HR-TEM images provided the first nanoscale observations of the fluid-mediated mineral dissolution and amorphous phase formation. This study also revealed that the mineral dissolution, element transport, and reprecipitation were significantly influenced by the fluid amorphous phase in the Nb-Ta deposits. [ABSTRACT FROM AUTHOR]

Objective. The objective is to explore the effectiveness and safety of CAR T-cell therapy in advanced relapsed/refractory central nervous system B-cell lymphoma and compare the impact of autologous stem cell transplantation (ASCT) plus CAR T-cell therapy versus sequential CART therapy on the survival of patients. Methods. The retrospective analysis was based on the data of 17 patients with advanced relapsed/refractory central nervous system B-cell lymphoma. Bridging chemotherapy was applied before CAR T-cell infusion to further reduce the tumor burden. For patients with autologous hematopoietic stem cell successful collection, CD19/20/22CAR T-cell immunotherapy following ASCT was performed with the thiotepa-containing conditioning regimen, while sequential CD19/CD20/CD22CAR T-cell therapy was applied. For lymphodepletion, patients received bendamustine or fludarabine monotherapy or fludarabine combined with cyclophosphamide pre-CART-cell infusion. Results. Out of the 17 patients, 8 completed ASCT plus CART cell therapy, while 9 patients completed CART cell alone therapy. In efficacy assessment at 3 months after infusion, the objective response rate (ORR) was 12/17 (71%) and the complete response rate (CRR) was 11/17 (65%). The CRR of the ASCT group and non-ASCT was 100% and 44.4%, respectively (P < 0.01). The median progression-free survival was 16.3 (2.6–24.5) months, and the median overall survival was 19.3 (6–24.5) months. Patients who underwent ASCT plus CART cell therapy had significantly longer PFS (P < 0.01) and OS (P < 0.01). Grade 3 or higher immune effector cell-associated neurologic toxicity syndrome (≥grade 3 ICANS) and cytokine release syndrome (≥grade 3 CRS) events occurred in 29% and 41% of the patients, respectively. No treatment-related death occurred. Conclusion. The CAR T-cell therapy could augment its efficacy in the treatment of advanced relapsed/refractory CNS B-cell lymphoma, while ASCT in combination with CART can induce durable responses and OS with a manageable side effect. [ABSTRACT FROM AUTHOR]

Ischemic stroke is a cerebrovascular disease with a high morbidity and mortality rate, which poses a serious challenge to human health and life. Meanwhile, the management of ischemic stroke remains highly dependent on manual visual analysis of noncontrast computed tomography (CT) or magnetic resonance imaging (MRI). However, artifacts and noise of the equipment as well as the radiologist experience play a significant role on diagnostic accuracy. To overcome these defects, the number of computer-aided diagnostic (CAD) methods for ischemic stroke is increasing substantially during the past decade. Particularly, deep learning models with massive data learning capabilities are recognized as powerful auxiliary tools for the acute intervention and guiding prognosis of ischemic stroke. To select appropriate interventions, facilitate clinical practice, and improve the clinical outcomes of patients, this review firstly surveys the current state-of-the-art deep learning technology. Then, we summarized the major applications in acute ischemic stroke imaging, particularly in exploring the potential function of stroke diagnosis and multimodal prognostication. Finally, we sketched out the current problems and prospects. [ABSTRACT FROM AUTHOR]

The semisupervised semantic segmentation method uses unlabeled data to effectively reduce the required labeled data, and the pseudo supervision performance is greatly influenced by pseudo labels. Therefore, we propose a semisupervised semantic segmentation method based on mutual correction learning, which effectively corrects the wrong convergence direction of pseudo supervision. The well-calibrated segmentation confidence maps are generated through the multiscale feature fusion attention mechanism module. More importantly, using internal knowledge, a mutual correction mechanism based on consistency regularization is proposed to correct the convergence direction of pseudo labels during cross pseudo supervision. The multiscale feature fusion attention mechanism module and mutual correction learning improve the accuracy of the entire learning process. Experiments show that the MIoU (mean intersection over union) reaches 75.32%, 77.80%, 78.95%, and 79.16% using 1/16, 1/8, 1/4, and 1/2 labeled data on PASCAL VOC 2012. The results show that the new approach achieves an advanced level. [ABSTRACT FROM AUTHOR]

Objective. In order to verify the safety and effectiveness of tirofiban combined with statins in the perioperative period of intracranial aneurysms, this study adopts systematic review and meta-analysis, so as to comprehensively understand the situation of intracranial aneurysms in the perioperative period, and tirofiban combined with statins was finally determined as an effective treatment drug. Methods. This study used systematic retrospective analysis and selected 80 patients with intracranial aneurysms treated in our hospital from June 2021 to June 2022 as the research objects. Through conventional drugs and tirofiban combined with statins used in this study, the intracranial levels, the probability of aneurysm rupture, and postoperative complications of the two groups were observed and recorded. Results. The analysis of 80 patients with intracranial aneurysms showed that the influence of intracranial levels in the observation group was better than that in the reference group, the rupture of aneurysms in the observation group was lower than that in the reference group, and the incidence of postoperative complications in the observation group was lower than that in the reference group. Conclusion. Through simulation verification, it is concluded that tirofiban combined with statins is safe and effective in the perioperative application of intracranial aneurysms. This drug can improve vascular recanalization, reduce the incidence of cerebrovascular disease events, and reduce the incidence of rebleeding. Its therapeutic effect is worthy of wide clinical application and promotion. [ABSTRACT FROM AUTHOR]

Effective perception of the surrounding environment and the balance between accuracy and processing speed are crucial for the successful application of real-time semantic segmentation algorithm in the fields of autonomous driving, drones, and smart security. In this paper, a lightweight feature reuse network MHANet for real-time semantic segmentation is proposed. The main novelties of our method are improved ResNet and attention-based fusion mechanism. And the effectiveness of our method is verified by a large number of experiments. Without any pre-training process, the performance of real-time segmentation is improved by using deep fusion of segmentation maps with different resolutions. At the same time, our network converges faster than other networks using pre-training when trained from scratch. Compared with existing methods, the results obtained with our method on the Camvid dataset improve in accuracy (mIoU) ranging from 2% to 6% and in efficiency (FPS) ranging from 15% to 18%. The results achieved 71.87% mIoU of accuracy in the Cityscapes test set, processing images at 203 FPS. Experiments show that manual designed MHANet is effective in improving the performance of real-time semantic segmentation without any pre-training. [ABSTRACT FROM AUTHOR]

It is thought to be an effective technique to handle the problem of educational data explosion and lack of information by identifying potential relationships between data and directing decision-makers through the extraction, transformation, analysis, and modeling of educational data. Based on this, this research constructs a data analysis model for education evaluation using the K-means clustering technique in DM. The weight of each index of students' comprehensive quality is calculated using AHP, and the value of the weight is used to determine whether the index is the important feature of analysis system mining. Improved sampling technology is used to deal with the representation of large-scale data sets; a sample partition clustering technique is proposed as a general framework. The best accuracy of this method, according to experimental data, is 95.6 percent, which is 12.1 percent greater than Mi cluster algorithm and 6.8 percent higher than DRCluster algorithm. The K-means clustering analysis technology is used to analyze students' comprehensive evaluation data in this paper, with the goal of determining the regularity of data implication, accurately diagnosing learning problems, and providing the foundation for developing effective student management strategies. [ABSTRACT FROM AUTHOR]

This study is aimed at performing a systematic review and a network meta-analysis of the effects of several membranes on vertical bone regeneration and clinical complications in guided bone regeneration (GBR) or guided tissue regeneration (GTR). We compared the effects of the following membranes: high-density polytetrafluoroethylene (d-PTFE), expanded polytetrafluoroethylene (e-PTFE), crosslinked collagen membrane (CCM), noncrosslinked collagen membrane (CM), titanium mesh (TM), titanium mesh plus noncrosslinked (TM + CM), titanium mesh plus crosslinked (TM + CCM), titanium-reinforced d-PTFE, titanium-reinforced e-PTFE, polylactic acid (PLA), polyethylene glycol (PEG), and polylactic acid 910 (PLA910). Using the PICOS principles to help determine inclusion criteria, articles are collected using PubMed, Web of Science, and other databases. Assess the risk of deviation and the quality of evidence using the Cochrane Evaluation Manual, and GRADE. 27 articles were finally included. 19 articles were included in a network meta-analysis with vertical bone increment as an outcome measure. The network meta-analysis includes network diagrams, paired-comparison forest diagrams, funnel diagrams, surface under the cumulative ranking curve (SUCRA) diagrams, and sensitivity analysis diagrams. SUCRA indicated that titanium-reinforced d-PTFE exhibited the highest vertical bone increment effect. Meanwhile, we analyzed the complications of 19 studies and found that soft tissue injury and membrane exposure were the most common complications. [ABSTRACT FROM AUTHOR]

This paper proposes corresponding teaching methods and instructional modes based on predecessors' research on mathematics instructional mode and the current state of mathematics teaching. In addition, this paper constructs a teaching evaluation model based on DL algorithm based on an in-depth study of DL-related theories in order to accurately and scientifically analyze the problems that exist in mathematics teaching. This paper constructs an instructional quality evaluation index system based on rationality and fairness, and uses the BPNN evaluation model to train and study a set of instructional quality data. Finally, the experimental results show that this system has a high level of stability, with a 96.37 percent stability rate and a 95.42 percent evaluation accuracy rate. The results of this paper's evaluation of the mathematical instructional quality model are objective and reasonable. It can accurately assess instructional quality while also assessing problems in the teaching process based on the instructional quality scores and making reasonable recommendations for teaching improvement based on the weak links in the teaching process. It has the potential to provide a workable system for assessing instructional quality. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC) is a kind of inflammatory bowel disease. Procyanidins have been found to prevent UC. However, most research has been focused on the alleviation effect of B‐type procyanidins on UC and ignored those of A‐type procyanidins. Hence, this study aims to investigate the anti‐UC effect and the potential mechanism of A‐type procyanidins by combining gut microbiome and metabolic profile. UC was induced by dextran sulfate sodium (DSS) in Balb/c mice, and then the mice were administrated with peanut skin procyanidins (PSP; rich in A‐type procyanidins) for 9 days. Administration of PSP can ameliorate DSS‐induced UC by mediating the intestinal barrier, the expression of inflammatory cytokines (TNF‐α, IL‐β, IL‐6, and IL‐10) and oxidative stress (MDA, T‐SOD, NO, and iNOS) in mice. We observed that PSP affects the gut microbiota and colon metabolomic patterns of mice. The 16S rDNA sequencing showed increase in abundance of Lachnospiraceae_NK4A136_group, Oscillibacter and Roseburia and decrease of Bacteroides, Helicobacter, Parabacteroides, Escherichia‐Shigella, and Enterobacter after PSP treatment. The colon tissue metabolome was significantly altered, as reflected by regulating taste transduction, mTOR signaling pathway, PI3K‐Akt signaling pathway, and FoxO signaling pathway to improve the protection against UC. Practical applications: We investigated the anti‐ulcerative colitis (UC) effect and its potential mechanism of peanut skin procyanidins (PSP). This suggests that PSP with abundant A‐type procyanidins may be an effective candidate for dietary supplementation to alleviate the symptoms of UC by regulating gut microbiota and metabolism. [ABSTRACT FROM AUTHOR]

Objective. The therapeutic effect of drugs for functional dyspepsia (FD) is still limited. Ganoderic acid A (GAA) has anti-inflammatory and cellular protective activities. The aim of this study is to explore the therapeutic effect of GAA on FD. Methods. The FD rat model was established via tail damping and forced exercise fatigue. The gastric emptying rate and intestinal propulsion rate of the rats in each group were then detected, and the pathological damage of gastric antrum and duodenum tissues was observed by hematoxylin-eosin (HE) staining. An enzyme-linked immunosorbent assay (ELISA) was conducted to determine the levels of motilin (MTL), vasoactive intestinal peptide (VIP), leptin, gastrin (GAS), calcitonin gene-related peptide (CGRP), and somatostatin (SS) in plasma, and Western blot was used to detect the protein expression levels of occludin, zonula occluden-1 (ZO-1), and junctional adhesion molecule-1 (JAM-1) in the duodenal tissue. Results. Treatment with GAA significantly raised the gastric emptying rate and intestinal propulsion rate of FD rats and histologically alleviated the gastric and duodenal damage. Meanwhile, GAA positively regulated the secretion of brain-gut proteins, such as upregulation of MTL, GAS, and SS and downregulation of VIP, leptin, and CGRP. In addition, GAA treatment increased the protein expression levels of occludin, ZO-1, and JAM-1 in the duodenal tissue of the FD rats. Conclusion. GAA may exhibit protective effects on FD by regulating the secretion of brain-gut peptide, protecting the intestinal barrier and improving gastrointestinal motility. [ABSTRACT FROM AUTHOR]

With the expansion of college enrollment, the number of college students is increasing, and the amount of information to be dealt with in the information management of college students is increasing. In most colleges and universities, managing college student information is done artificially. In this context, how to effectively manage and utilize the dance big data of college students has important research value. Therefore, this article takes the development and realization of student dance under the public service platform system of colleges and universities as the subject and design the university dance big data management and utilization system based on information resource sharing. Due to the high mobility of college students, this work also carries out an information resource sharing strategy to establish the dance big data management and utilization system for universities; after the implementation of the student dance big data management service system, colleges and universities can provide more convenient transfer, management, query, and other services of student files. [ABSTRACT FROM AUTHOR]

Hyssopus cuspidatus Boriss (H. cuspidatus) is a traditional Chinese medicine commonly used in the treatment of asthma. In the present study, we applied bioinformatics techniques for mRNA-miRNA profiling to elucidate the potential mechanisms of H. cuspidatus in asthma treatment. Bioactive compounds from H. cuspidatus, potential therapeutic targets of H. cuspidatus, and asthma-related targets were identified from the literature and databases. The intersection of H. cuspidatus-related targets and asthma-related targets was identified using the STRING platform. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using the Metascape platform. Networks were constructed from these nodes using Cytoscape. The results showed that 23 active compounds were identified in H. cuspidatus, sharing 122 common asthma-related targets. Moreover, 43 miRNAs regulating 19 key targets involved in the antiasthmatic effects of H. cuspidatus were identified. Further analysis of biological pathways, active compound-key target-pathway network, and active compound-key target-miRNA network indicated that the antiasthmatic effects of H. cuspidatus mainly occurred through caffeic acid, methyl rosmarinate, luteolin, esculetin, and 8-hydroxycirsimaritin. These compounds interacted with multiple miRNAs, including miR-99a, miR-498, miR-33b, and miR-18a, regulating multiple genes, including JAK, STAT3, EGFR, LYN, and IL-6, in multiple pathways, including those involved in the regulation of JAK-STAT signaling, EGFR tyrosine kinase inhibitor resistance, PI3K-Akt signaling, and inflammation. In summary, we have elucidated the potential mechanisms of H. cuspidatus treatment of asthma from a systemic and holistic perspective through analysis of compound-mRNA-miRNA interaction. Our study should provide new insights for further research on H. cuspidatus treatment of asthma. [ABSTRACT FROM AUTHOR]

Background. Cancer-related fatigue (CRF) is a painful, persistent feeling of physical and cognitive subjective fatigue related to cancer or cancer remedy. The occurrence of CRF may be related to the hypothalamic-pituitary-adrenaline (HPA) axis, inflammatory mediator theory, and gut microbiota. Moreover, acupuncture could play a vital part in the therapy of CRF. The study will evaluate whether acupuncture can improve fatigue symptoms of CRF patients after breast cancer chemotherapy by regulating the gut-brain axis. Methods/design. Seventy patients with CRF will be enrolled in this study, with 35 patients randomly assigned to each group. Blood and feces will be collected at the beginning and end of treatment. Piper fatigue scale, KPS score scale, and quality-of-life scale will be used to observe the changes of fatigue symptoms and life quality of CRF patients and to evaluate the effect of acupuncture on CRF. Then, the method of ELISA will be used to explore the regulatory effect of acupuncture on the HPA axis and inflammatory cytokines. Moreover, based on 16SrDNA, the changes of gut microbiota structure and flora of CRF patients will be observed. Ultimately, the correlation analysis of gut microbiota can be related to inflammatory cytokines, HPA axis, and clinical efficacy evaluation. Discussion. This study will identify the effect and the mechanism of acupuncture therapy in CRF. And it will offer an alternative treatment modality for the treatment of CRF after chemotherapy for breast cancer. Furthermore, it will also provide the clinical and theoretical bases for the extensive application of acupuncture therapy in tumor rehabilitation. Trial Status. Protocol version number and date: V2.0, 6 May 2021. The trial is registered with the Chinese Clinical Trial Registry on 20 June 2021 (trial identifier: ChiCTR2100047510). [ABSTRACT FROM AUTHOR]

By considering the comprehensive impact index ranking of all factors to identify the impact of university innovation knowledge, the group decision-making characteristic root method, decision-making experiment, and evaluation laboratory method are used to analyze the factors that affect the university's innovative knowledge management ability. The key factors affecting management capabilities have been identified and reviewed to establish measures to enhance the innovative knowledge management capabilities of colleges and universities. Using artificial intelligence-based knowledge management fuzzy evaluation algorithm evaluation model to evaluate the innovation knowledge management of 16 universities, the results obtained are consistent with the actual evaluation results of the year; this result proves the fuzziness of university innovation knowledge management, which is based on artificial intelligence fuzzy. The algorithm is evaluated. The results show that the evaluation model is feasible. [ABSTRACT FROM AUTHOR]

With the development of Internet economy and the advent of artificial intelligence era, the transformation from financial accounting to management accounting has become an inevitable trend of financial management among companies. In this paper, the significance of the transformation from financial accounting to management accounting is expounded under the background of artificial intelligence, and the current situation, problems and reasons of the transition are analyzed. In addition, the development of self-management accounting system based on Drools rule engine is put forward, including rule management, rule engine and so on. The core processes such as pattern matching and auto-billing are analyzed, and then the core subsystems such as data receiving and processing, accounting rule engine are designed in detail. Finally, the technological advancement and structural stability of this system are discussed, which can provide reference for promoting the transformation from financial accounting to management accounting under artificial intelligence. [ABSTRACT FROM AUTHOR]

Background. Bone loss is common in patients with inflammatory bowel disease (IBD). The aim of the present study was to determine the prevalence of metabolic bone disease in patients newly diagnosed with IBD and to identify the risk factors for bone loss over time. Methods. We performed a retrospective, both cross-sectional and longitudinal, study to extract the risk factors of bone loss (including osteopenia and osteoporosis) in patients newly diagnosed with IBD, using dual-energy X-ray absorptiometry (DXA). Results. A total of 639 patients newly diagnosed with IBD that had at least one DXA were included in the cross-sectional study. Osteopenia and osteoporosis were diagnosed in 24.6% and 5.4% of patients, respectively. Age at diagnosis, body mass index, and serum phosphorus were identified as independent factors associated with bone loss at baseline. A total of 380 of the 639 IBD patients (including 212 CD patients and 168 UC patients) with at least a second DXA scan were included in the longitudinal study. 42.6% of the patients presented a worsening of bone loss in the follow-up study. Menopause, albumin, and use of corticosteroids were identified as independent factors associated with worsening of bone loss. Conclusions. Metabolic bone disease is common in IBD patients, and there is a significant increase in prevalence of bone loss over time. Postmenopausal female, malnourished patients, and those requiring corticosteroid treatment are at risk for persistent bone loss. Therefore, BMD measurements and early intervention with supplementation of calcium and vitamin D are recommended in IBD patients with high-risk factors. [ABSTRACT FROM AUTHOR]

Due to the shortage of spectrum resources, a nonorthogonal multiple access- (NOMA-) based overlay cognitive integrated satellite-terrestrial relay network is established in this paper, where cognitive radio (CR) and NOMA scheme are utilized to enhance spectral efficiency. In this system, a secondary terrestrial transmitter assists the transmission of primary signal and transmits its own signal simultaneously. To maximize the achievable rate of a secondary network on the premise of ensuring the quality of service of primary network, the decoding order and power allocation are jointly optimized. Particularly, we first derive the optimal power allocation factor for a given decoding order. After searching all different decoding orders, the globally optimal joint design of the decoding order and power allocation is obtained. To gain deep insights, the exact and asymptotic expressions for outage probability of both primary and secondary networks are derived. Numerical results demonstrate the accuracy of our derivation and indicate the impacts of key parameters on the proposed system. [ABSTRACT FROM AUTHOR]

In this paper, we investigate downlink transmission schemes robust to the Doppler frequency offset (DFO) induced by high mobility for low earth orbit multiple-input and multiple-output satellite communication systems. Considering the impact of DFO, we derive the closed-form expressions for the downlink achievable rates with maximum ratio transmission (MRT) and maximum average signal-to-leakage-plus-noise ratio (MASLNR) precoding. Numerical results show that the derived closed-form expressions are accurate and the DFO severely affects system performance. In order to relieve the impact of DFO, we propose an adaptive DFO compensation algorithm based on the precompensation design and beam alignment. Numerical results verify the effectiveness of the proposed DFO compensation algorithm. [ABSTRACT FROM AUTHOR]

Objective. To explore the application effect of a whole-process seamless nursing model based on the smart healthcare mode in the perioperative period of patients undergoing hematoma removal. Methods. In this retrospective study, 50 patients with hematoma removal admitted to our hospital from August 2018 to August 2019 were included as the control group (CG), while 50 patients with hematoma removal admitted to our hospital from September 2019 to September 2020 were included as the experimental group (EG). During the period of hematoma removal, CG received routine perioperative nursing, while EG received the whole-process seamless nursing model based on the smart healthcare mode. The perioperative indexes, hemodynamic indexes, and the incidence of postoperative complications were compared between the two groups, and the incidence of nursing staff's work omissions in different periods was analyzed. Results. Notable differences were observed in surgical time, intraoperative blood loss, hematoma clearance rates, length of ICU stay, hospitalization time, removal time of ventricular drainage tube, and cerebral edema volume at 1 week after surgery between EG and CG (P < 0.05). Compared with CG, EG achieved obviously better hemodynamic indexes (P < 0.001) and a lower incidence of bedsore, muscle atrophy, and eating/swallowing disorders (P < 0.05). During the implementation of smart healthcare, the incidence of nursing staff's work omissions was remarkably reduced (P < 0.05). Conclusion. Under the smart healthcare, the incidence of nursing staff's work omissions is lower, and the effect of the whole-process seamless nursing is better, which can optimize the perioperative indexes of patients, stabilize the postoperative hemodynamics, and reduce the incidence of complications. Therefore, the whole-process seamless nursing model based on the smart healthcare mode has promotion value in clinic. [ABSTRACT FROM AUTHOR]

Satellite communication is becoming more and more significant in present and future communication systems for its unique advantages of strong survivability and seamless coverage, which can offset the defects of terrestrial communication such as being restricted by terrain and little coverage. Moreover, unmanned aerial vehicle (UAV)-assisted communication is considered as a promising development direction due to its flexibility and expansibility in the integrated satellite-terrestrial networks (ISTN). In addition, to overcome the spectrum shortage and low spectrum utilization problems, cognitive radio and nonorthogonal multiple access (NOMA) has been widely utilized to enhance spectrum efficiency, which is considered as the key technologies of the next generation communication. In this regard, our paper investigates the performance of cognitive satellite-UAV-terrestrial networks with NOMA scheme and multiple primary users. Specifically, the exact expressions of outage probability (OP) and ergodic capacity for both primary network and secondary network are derived. To gain further views, the asymptotic expression of OP and diversity orders for the two networks are provided. Finally, through numerical simulations, the correctness of the theoretical derivations is verified and the influences of critical variables on system indexes are also analyzed. [ABSTRACT FROM AUTHOR]

Background. Mechanical ventilation (MV) can provoke acute lung injury (ALI) by increasing inflammation activation and disrupting the barrier in lung tissues even causing death. However, the inflammation-related molecules and pathways in MV-induced ALI remain largely unknown. Hence, the purposes of this study are to examine the role and mechanism of a novel inflammation-related molecule, leukotriene B4 (LTB4), in ALI. Methods. The functions of LTB4 in one-lung ventilation (OLV) model were detected by the loss-of-function experiments. H&E staining was used to examine the pathologic changes of lung tissues. Functionally, PLCε-1 knockdown and Toll-like receptor 4 (TLR4)/NF-κB pathway inhibitor were used to detect the regulatory effects of LTB4 on the phospholipase Cε (PLCε-1)/TLR4/nuclear factor-kappa B (NF-κB) pathway. The levels of genes and proteins were determined by RT-qPCR and western blotting assay. The levels of inflammation cytokines and chemokines were measured by ELISA. Results. Here, we found LTA4H, leukotriene B (4) receptor 1 (BLT1), LTB4, and PLCε-1 upregulated in OLV rats and associated with inflammatory activation and lung permeability changes of lung tissues. Inhibition of LTB4 alleviated the OLV-induced ALI by inhibiting inflammatory activation and lung permeability changes of lung tissues. For mechanism analyses, LTB4 promoted OLV-induced ALI by activating the PLCε-1/TLR4/NF-κB pathway. Conclusion. LTB4 induced ALI in OLV rats by activating the PLCε-1/TLR4/NF-κB pathway. Our findings might supply a new potential therapeutic for OLV-induced ALI. [ABSTRACT FROM AUTHOR]

In this paper, we propose a multiresidual module convolutional neural network-based method for athlete pose estimation in sports game videos. The network firstly designs an improved residual module based on the traditional residual module. Firstly, a large perceptual field residual module is designed to learn the correlation between the athlete components in the sports game video within a large perceptual field. A multiscale residual module is designed in the paper to better solve the inaccuracy of the pose estimation due to the problem of scale change of the athlete components in the sports game video. Secondly, these three residual modules are used as the building blocks of the convolutional neural network. When the resolution is high, the large perceptual field residual module and the multiscale residual module are used to capture information in a larger range as well as at each scale, and when the resolution is low, only the improved residual module is used. Finally, four multiresidual module convolutional neural networks are used to form the final multiresidual module stacked convolutional neural network. The neural network model proposed in this paper achieves high accuracy of 89.5% and 88.2% on the upper arm and lower arm, respectively, so the method in this paper reduces the influence of occlusion on the athlete's posture estimation to a certain extent. Through the experiments, it can be seen that the proposed multiresidual module stacked convolutional neural network-based method for athlete pose estimation in sports game videos further improves the accuracy of athlete pose estimation in sports game videos. [ABSTRACT FROM AUTHOR]

The feature extraction of high-precision microseismic signals is an important prerequisite for multicategory recognition of microseismic signals, and it is also an important basis for intelligent sensing modules in smart mines. Aiming at the problem of unobvious feature extraction of multiclass mine microseismic signals, this paper is based on the unsupervised learning method in the deep learning method, combined with wavelet packet energy ratio and empirical modulus singular value decomposition, and proposes a method based on wavelet packet energy and empirical modulus singular value decomposition and proposes a method (M-W&E) based on wavelet packet energy and empirical modulus singular value decomposition. This method firstly performs empirical modulus singular value decomposition and wavelet packet energy ratio on the microseismic signal to construct the basic feature vector and then uses the unsupervised learning algorithm to perform the unsupervised learning method feature fusion of the basic feature vector to construct the fused feature vector. After visualization by t-SNE, various distinctions in the fusion feature vector are more obvious. After testing the fusion feature classification using SVM, it is found that the recognition rate of the new feature after feature fusion is better than that of a single wavelet packet empirical energy component and singular value of empirical modulus, which basically meets the engineering needs and is a mine microseism. The signal extraction and feature enhancement fusion of multiclass samples provide a new idea. [ABSTRACT FROM AUTHOR]

Word sense disambiguation (WSD) is an important research topic in natural language processing, which is widely applied to text classification, machine translation, and information retrieval. In order to improve disambiguation accuracy, this paper proposes a WSD method based on the graph convolutional network (GCN). Word, part of speech, and semantic category are extracted from contexts of the ambiguous word as discriminative features. Discriminative features and sentence containing the ambiguous word are used as nodes to construct the WSD graph. Word2Vec tool, Doc2Vec tool, pointwise mutual information (PMI), and TF-IDF are applied to compute embeddings of nodes and edge weights. GCN is used to fuse features of a node and its neighbors, and the softmax function is applied to determine the semantic category of the ambiguous word. Training corpus of SemEval-2007: Task #5 is adopted to optimize the proposed WSD classifier. Test corpus of SemEval-2007: Task #5 is used to test the performance of WSD classifier. Experimental results show that average accuracy of the proposed method is improved. [ABSTRACT FROM AUTHOR]

In the field of basketball, the formulation of the existing training plan mainly relies on the coaches' artificial observation and personal experience, which is inevitably subjective. The application of body domain network technology in athletes' training and recognition of athletes' postures can help coaches to assist decision-making and greatly improve athletes' competitive ability. The human movements reflected in basketball are more complex which need deep understanding. The accuracy of basketball players' shooting movements recognition plays a positive and important role in basketball games and training practice. Based on the prior knowledge of the convolutional neural network study, environment light conditions change the dynamic characteristics of basketball image analysis, capture images of the basketball goal algorithm of minimum circumscribed rectangle of the object, and based on the convolutional neural network, introduce two types of prior knowledge, one kind is based on the feature matching method that defined a priori knowledge, while another kind is based on training the convolution neural network model. The test results of the network model are taken as the prior knowledge, and then, a convolutional neural network dynamic target recognition model is constructed based on the prior knowledge. The construction process of the model is organized as the basketball target image is collected under any illumination conditions, the convolutional neural network model is trained with the convolutional neural network as the input data, and the standard illumination conditions are determined according to the test results of the network model. Then, put it into the trained network model to test and get the recognition results of basketball players' shooting movements. The research is validated with performing experiments and the results revealed the success of the study. [ABSTRACT FROM AUTHOR]

With the development of smart manufacturing, quality has become an indispensable issue in the manufacturing process. Although there is increasing publication about inspection allocation problems, inspection allocation optimization research considering resource capability is scarce. This paper focuses on the inspection allocation problem with resource constraints in the flexible manufacturing system. Combined with the inspection resource capability model, a bi-objective model is developed to minimize the cost and balance loads of the inspection station. A modified NSGA-II algorithm with adaptive mutation operators is suggested to deal with the proposed model. Finally, a simulation experiment is conducted to test the performance of the modified algorithm and the results demonstrate that modified NSGA-II can obtain acceptable inspection solutions. [ABSTRACT FROM AUTHOR]

Summary: The irreversible capacity fade, low Coulombic efficiency and sulfur utilization rate caused by the "shuttle" of polysulfides are serious drawbacks of lithium sulfur (Li‐S) battery. Here, a regular octahedral structure and abundant hierarchical porous S/MIL‐101(Cr)‐H, as the electrode of Li‐S battery to catch and anchor polysulfides for alleviating the "shuttle effect" and strengthening the utilization of S, were synthesized by usual hydrothermal and facile heat treatment. Consequently, compared with S/MIL‐101(Cr) (719.52 mA h g−1), S/MIL‐101(Cr)‐H shows better initial discharge capacity (1073.59 mA h g−1) and the reversible capacity remains (446.59 mA h g−1) after 100 cycles at 0.1C, which is much greater than S/MIL‐101(Cr). A capacity of 504.26 mA h g−1 and Coulombic efficiency of approximately 95% at 0.5 C were obtained. The better electrochemical property is ascribed to the coordinated effect of the adsorption of microporous structure and chemical bonding of Cr‐S, which can effectively capture the soluble polysulfides and alleviate "shuttle effect" through physical confinement and chemical anchoring. [ABSTRACT FROM AUTHOR]

Almond oil has been used as a medicine substitution for its numerous health benefits. This study aimed to evaluate the effect of almond oil on streptozotocin- (STZ-) induced diabetic rats for 4 weeks. The results showed that the administration of almond oil could significantly increase body weight, attenuate abnormally elevated blood glucose, promote insulin secretion, and improve glucose tolerance. Almond oil treatment also suppressed oxidative stress, reduced inflammation reaction, improved liver and kidney function, upregulated the expressions of Nrf2, HO-1, and NQO1, while downregulating the expression of Keap1. Furthermore, almond oil reversed the gut microbiota change by STZ and regulated the gut microbiota associated with glucose metabolism. At the phylum level, the relative abundance of Firmicutes was decreased, while Bacteroidetes was increased by almond oil treatment. More importantly, the ratio of Firmicutes/Bacteroidetes was significantly increased. At the genus level, administration of almond oil increased the abundances of Lactobacillus, Bacteroides, and Lachnospiraceae_NK4A136_group, while decreased the abundances of Ruminococcaceae_UCG-014, Clostridium_sensu_stricto_1, and Fusicatenibacter. These results provided evidence for the regulating effect of almond oil on diabetic rats via the Nrf2/HO-1 pathway and gut microbiota. [ABSTRACT FROM AUTHOR]

In this paper, through the study of elderly care, the method of equalizing the topological layout of the health care infrastructure network is used for in-depth analysis. With the evaluation method of senior care facility fairness as the research base theory, the analysis and evaluation of senior care facilities are carried out from two aspects of supply and demand fairness and spatial fairness, and the problems and shortcomings of senior care facilities in terms of facility scale, spatial layout, service level, and policy management are summarized. This paper analyses the contradictory points of the nonequitable layout of urban senior care facilities, to propose planning suggestions and optimization measures for the planning of the senior care service facility system. It discusses the problems in the spatial layout of senior care facilities from the perspective of social equity, focuses on the needs of urban disadvantaged groups, promotes the equalization of public services, and provides the theoretical basis and technical support for the planning policy of urban public service facilities. The study fully combines the theory of urban planning disciplines with geographic information system technology, mathematical and statistical technology, and network data acquisition technology to establish the evaluation of the spatial layout of senior care facilities based on social equity framework, to contribute to the planning of similar urban public service facilities. It comes to make an integrated consideration of the supply content and scope of basic public service facilities and check the gaps, which is conducive to improving the scientific and intensive nature of public resource input according to local conditions and more speed and provides some reference to the method of public service facility allocation. [ABSTRACT FROM AUTHOR]

The mining of manganese brings excellent wealth to humankind. However, it destroys the ecological environment, mainly manifested as heavy metal pollution and vegetation destruction. The restoration of ecological vegetation in manganese mining areas has become an important work after mineral exploitation. The effect of bryophytes on ecological restoration in mining areas is irreplaceable. The bryophytes diversity and its pioneering role in two types of manganese waste residue areas were investigated in Guizhou province, China. The results showed that there were 24 species of mosses in mine waste slag areas, and all of them belonged to 6 families and 15 genera; the species Gymnostomum subrigidulum, Pohlia gedeana, and Bryum atrovirens were the dominant mosses. There were 6 species of mosses in electrolytic manganese slag areas, and all of them belonged to 5 families and 5 genera. The dominant moss was B. atrovirens. The bryophytes diversity in the electrolytic manganese slag areas with lower pH was poorer than that in mine slag areas. The accumulation of heavy metals in mosses showed that B. atrovirens collected from two types of areas had a strong ability to accumulate Mn with the cumulants 5588.00 μg/g and 4283.41 μg/g, respectively. All mosses had a strong enrichment ability to Cd. It indicated that mosses had strong tolerance to heavy metals. Bryophytes increased the available nutrients and bacterial community diversity of mosses growth substrates in two types of areas. Besides, we studied the relationships between bacterial community structure and soil factors. The main soil factor affecting the bacterial community structure was available nitrogen (AN) in mine waste slag areas, while it was pH in the electrolytic manganese residue areas. The systematic study suggested that bryophytes increased the available nutrients and the microbial community diversity of the growth substrates in manganese waste residue areas, which provided the basic conditions for the growth of vascular plants. [ABSTRACT FROM AUTHOR]

The spatiotemporal agglomeration of industries is the most prominent geographical feature of economic activities. Based on the analysis of the spatiotemporal distribution of China's construction industry agglomeration, this paper analyzes the characteristics and evolution trend of the spatiotemporal agglomeration of construction industry in 31 provinces and cities of China from 2010 to 2019 by using Moran's index and the spatiotemporal transition measurement model. The findings are as follows: (1) China's construction industry has experienced two stages in terms of time: steady rise and turbulent rise. Spatially, China's construction industry, as a whole, the space takes the shape of one horizontal and two vertical, similar to the letter "H" being crossed. And the difference of "East-West" two ends of the industrial agglomeration level is obvious. (2) The Yangtze River Delta Urban Agglomerations (Shanghai, Jiangsu, and Zhejiang), the Pearl River Delta Urban Agglomerations (Guangdong), Beijing-Tianjin-Hebei Urban Agglomerations, and the western region (Xinjiang and Tibet) have significant local features. The four major types of China's construction industry cluster, which are H-H, H-L, L-H, and L-L, are formed. (3) The time-space transition of China's construction industry is dominated by the "stable transition" mode. The transition inertia is significant. The regional development has strong path dependence and spatial locking characteristics. [ABSTRACT FROM AUTHOR]

Large-area goafs in a gypsum mine tend to collapse after 10 or more years, but the influencing factors are still unclear, and the effects of multiple factors have not been comprehensively considered. In this study, the failure mechanism and collapse mode of the room-pillar goaf structure were analyzed, and the uniaxial compressive strength tests of the pillars under different conditions were carried out in a laboratory. The influences of water, temperature, and time on the strength of the gypsum rock were considered. These three factors weakened the gypsum rock in different degrees. After 120 days of immersion, water had the greatest effect with a strength-weakening rate of 52.61%. After 20 temperature cycles, changes in temperature had little effect with a strength-weakening rate of 12.60%. After 25 years of aging, the strength-weakening rate of time was 25.13%. These results show how different factors affect the instability and collapse of the goaf structure, which are of great significance for predicting and preventing this from happening. [ABSTRACT FROM AUTHOR]

In order to study the influence of burial depth or fire on the core area of cemented paste backfill (CPB), the experiment of CPB with different types of binder and temperature was carried out. Three types of binders, red mud (RM), Portland cement (PC), and slag cement (SC), are used and tested at 20°C, 40°C, 60°C, and 80°C. The macroperformance and microstructural evolution of CPB are analyzed using slump, uniaxial compressive strength (UCS), X-ray diffraction, and scanning electron microscopy (SEM). The results show that the coupled effects of binder type and temperature have a significant impact on the macroscopic performance and microstructural evolution of CPB. The CPB slump prepared with three types of binder meets the production requirement of the mine. Regardless of curing temperature and curing time, the uniaxial compressive strength of CPB samples with PC and SC is much higher than that of CPB samples with red mud. When cured for 12 hours, the uniaxial compressive strength of CPB samples containing PC and SC increases first, then decreases, and finally increases again with the increase of temperature. However, with the increase of temperature, the uniaxial compressive strength of CPB samples containing RM only increases first and then decreases. When the curing temperature is less than 40°C, the main reason for the increase in UCS was attributed to the fact that the temperature increase accelerates the hydration reaction and improves the density of the sample. When the curing temperature is 60°C, the main reason for the decrease in UCS is the formation of the expansive ettringite (AFt) which destroys the internal spatial structure of the sample. When the curing temperature is 80°C, the UCS increases again due to the fact that such high temperature can destroy the crystal structure of AFt and harden the hydration product C-S-H gel. [ABSTRACT FROM AUTHOR]

Two-stroke spark ignition (SI) unmanned aerial vehicle (UAV) engines do not allow heavy knock and require a certain knock safety margin. However, weak knock can help the engine increase power output and reduce fuel consumption. To accurately extract the knock characteristics of engine vibration signals under the condition of weak knock, a signal feature extraction method based on the Mallat decomposition algorithm was proposed. Mallat decomposition algorithm can decompose the signal into two parts: a low-frequency signal and a high-frequency noise signal. The decomposed high-frequency noise is eliminated, and the low-frequency signal is retained as the characteristic domain signal. Simulation results show the effectiveness of the proposed algorithm. The engine vibration signal of a two-stroke SI UAV engine was decomposed into the low-frequency signal and the high-frequency signal by the Mallat decomposition algorithm. The low-frequency signal is taken as the knock characteristic domain signal component, and the wavelet packet energy method is used to verify the correctness of the obtained signal component. The relative energy parameter is calculated by using the knock characteristic domain signal component, which can be used as the determination index of knock intensity. This method provides a reference for the weak knock control of two-stroke SI UAV engines. [ABSTRACT FROM AUTHOR]

Based on the variation range of the stress lode angle, the in situ rock stress is divided into σ v -type stress field, σ H -type stress field, and σ h -type stress field. Through theoretical analysis, the principal stress difference distribution law and plastic zone distribution pattern around the roadway in different types of stress fields are obtained. Theoretical and numerical simulation calculation results show that under different stress lode angle conditions, the principal stress difference distribution of the surrounding rock of the roadway is greatly different, which has a direct effect on the shape and range of the plastic zone of the surrounding rock of the roadway. In the σ v -type stress field and the σ H -type stress field, the shape of the plastic zone of the roadway surrounding rock is mainly oval and "butterfly," while in the σ h -type stress field, the shape of the plastic zone of the roadway surrounding rock is mainly oval. The laboratory test proves that the stress gradient has an important effect on the damage degree of the surrounding rock of the roadway. The larger the stress gradient, the higher the strength of the rock mass and the more severe the damage. The change of the stress lode angle will affect the distribution law of the stress gradient of the surrounding rock of the roadway, thus affecting the degree of fragmentation of the surrounding rock. In type σ v and type σ H stress fields, the surrounding rock of the shoulder can be regarded as a key part of the roadway. In the σ h -type stress field, the plastic zones of the surrounding rocks of the roadway are more evenly distributed, and the damage range is less affected by θ. The influence law of the stress lode angle on the stability of the roadway has been well verified by field observation, and effective support measures have been proposed. [ABSTRACT FROM AUTHOR]

In this study, Brazilian splitting tests were conducted on sandstone samples subjected to drying and immersing at water pressures of 0, 1, and 3 MPa (immersion duration of 120 h). Investigation of the immersion effects of pressure water on the tensile characteristics of the samples revealed that their tensile strengths decreased with the immersion water pressure. Relative to a sandstone sample subjected to drying alone, immersing at water pressures of 0, 1, and 3 MPa reduced the tensile strength by 12.96%, 19.03%, and 30.16%, respectively. Although the immersed samples experienced splitting failure indicative of obvious brittle failure characteristics, decreases in the postpeak stress reduction rate with immersion water pressure revealed that the intensity of brittle failure weakened with pressure. Based on the obtained data, the deformation evolution process of the sandstone samples could be divided into five stages: deformation adjustment, formation of local deformation zones, local deformation zone propagation, failure surface formation, and sample failure. The water pressure aggravated the physicochemical reactions between water and the hydrophilic minerals in the sandstone, promoting argillisation, dissolution, and loss of hydrophilic minerals and interparticle cementitious materials. As a result of these immersion micromechanisms, the deterioration of the sandstone samples increased with the immersion water pressure, with the average porosities of the fracture surfaces at 0, 1, and 3 MPa increasing by 142.86%, 368.37%, and 593.88%, respectively, relative to the dried sample. As a result of these morphological changes, the sandstone samples subjected to water pressure immersion failed at small axial stresses with low levels of applied mechanical energy. [ABSTRACT FROM AUTHOR]