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In this paper, the similarity criterion and dimensionless conversion method combined with the elasticity condition and Hooke's law are used to derive the functional relationship of the maximum effective value of the vibration velocity between the prototype pump and the model pump. The seawater circulation pump of a nuclear power plant is used as the prototype pump, and the model pump is obtained by performance conversion and choosing the appropriate scale, and the vibration state of the model pump under different flow rates is measured and analyzed. The vibration data of the model pump through the function relationship to find out the vibration parameters of the prototype model pump, and compare with the vibration data of the seawater circulation pump in reality. It can be seen that with the increase of flow rate, the maximum effective value of the vibration velocity of both model and prototype decreases and then increases, and the relative error is small, the maximum value is 7.7757%. Therefore, it can be considered that the functional relationship of model pump converted to prototype pump derived in this paper can be used to analyze the vibration of the actual seawater circulation pump of coastal nuclear power plant.

Exopolysaccharides (EPS) are natural high polymers metabolized into the extracellular space by lactic acid bacteria during their growth. EPS have a broad spectrum of biological activities including antitumor, antioxidant, cholesterol-lowering, and intestinal microflora balance promoting functions. They can also be used as a food thickening agent, emulsifier, and stabilizer. Weissella, which was discovered recently, has a strong ability to produce EPS. This article mainly reviews the sources of Weissella and the synthesis pathway, classification, functions and application in fermented foods of EPS produced by Weissella. Hopefully, this review will provide a scientific basis for the processing and application of EPS from Weissella.

This paper starts from the connotation of the definition of sports, film art and youth cultural literacy, and after determining the corresponding independent variables and dependent variables, the quantile regression model is constructed using the least squares method. The research data is collected, and examples analyze the constructed regression model. The results showed that the multivariate correlation coefficient between the four performance types of sports film and television art and adolescent cultural awareness was 0.265, and the F-value of the overall test was 19.548 (P

The command control (C2) is the most important part of the war for all dynasties. In information age, the future battlefield poses new challenges for C2. By analyzing the characteristics of network enabled command and control in the information age, this paper studies the C2 function and approach space, defines five C2 archetype, discriminates in detail the objectives and requirements of each archetype, analyzes its maturity level and maturity migration model, and finally discusses the challenges to C2 in the future battlefield. It is important to help the combatant analyze the problems existing in current C2, to improve the C2 ability of the current and future, to improve the control of the commanders, and to improve the manage ability of complex, dynamic and uncertain combat missions.

High-voltage electric field treatment is an emerging approach to improve the cold flowability of crude oil, of which the physical principle is the negative electrorheological effect of crude oil other than electric heating and electric field dehydration. Based on the review of literatures on electrorheology, several mechanisms of negative electrorheological effect were summarized, and the problems in the electric field treatment mechanisms of crude oil, such as particle aggregation into chains, increasing the particle size of wax crystal, and enhancing the polydispersity, were analyzed. Besides, the basis of wax particle interface polarization was explained. Generally, the co-existence of wax particles, resins and asphaltenes is the necessary condition to realize the treatment effect of electric field. When a high-voltage electric field is applied, the charged particles(i.e. the resins and asphaltenes) in the crude oil would aggregate on the surface of wax crystal, which is the interface polarization. During the process, the electrostatic repulsion between wax particles is increased while their attraction is weakened, resulting in improved cold flowability of the crude oil. Therefore, the behavior of resins and asphaltenes in the oil is the key to understand the mechanism of the negative electrorheological effect of crude oil, which mainly includes three processes: the migration of resins and asphaltenes from the bulk phase to wax particles upon the application of electric field,accumulation of resins and asphaltenes on the surface of wax particles, and their diffusion back to the bulk phase after the removal of electric field. In the future, further in-depth and quantitative research should be focused on these three processes to fully reveal the scientific mechanism of the electrorheological effect of crude oil.

To make full use of the electric power system based on energy storage in a wind-solar microgrid, it is necessary to optimize the configuration of energy storage to ensure the stability of a multi-energy system. This paper analyses the structure and function of the microgrid system, establishes the mathematical model, and analyzes the output characteristics. A double-layer optimization model of energy storage system capacity configuration and wind-solar storage micro-grid system operation is established to realize PV, wind power, and load variation configuration and regulate energy storage economic operation. The mathematical model of the improved gray wolf optimization is constructed, and the typical landscape resource data of a residential district. Comparing the difference between energy storage without an installation and energy storage with improved algorithm, it is shown that the energy storage configuration of the improved gray wolf optimization improves the economy, efficient energy use, and revenue of the whole system.

Objective To investigate the expression and clinical significance of H3K27me3 in vascular hemangioma and malformation. Methods Paraffin-embedded tissue blocks from 244 patients with hemangioma and vascular malformation admitted in our hospital from January 2010 and June 2021 were collected. The expression levels of H3K27me3 and smooth muscle actin (SMA) in vascular endothelial and perivascular cells were detected by immunohistochemical SP assay, and its expression differences between hemangioma and vascular malformation was analyzed. Bioinformatics analysis was further applied to explore its potential role in anigodysplasia in combination of the results of SMA immunostaining. Receiver operating characteristic (ROC) curve was drawn to evaluate its diagnostic value in differentiation of hemangioma and vascular malformation. Results In vascular hemangioma, H3K27me3 expression was mainly restricted to vascular endothelial cells, with an expression rate of 50%~90%. However, in vascular malformations, it was expressed in vascular endothelial cells, with an expression rate of 30%~50%, and lost in perivascular cells. There were top 10 endothelium restricted genes derived from GSE21212 dataset based on concerning literatures. According to ChIP-seq data from ENCODE website, H3K27me3 was enriched in the SOX2 promoter of different endothelium lineages, and the molecular interaction of H3K27me3 and SOX2 may be associated with vessel development and differentiation. Conclusion The expression of H3K27me3 in vascular endothelial cells can be used as a candidate marker to distinguish hemangioma and vascular malformation. However, its expression in infantile hemangioma is immunologically heterogeneous.

This study aimed to examine whether nuclear receptor 4a1 (NR4A1) is involved in inhibiting hepatic stellate cell (HSC) activation and liver fibrosis through the epithelial–mesenchymal transition (EMT). HSC-T6 cells were divided into the control group, the acetaldehyde (200 μM, an EMT activator) group, and the NR4A1 activation group (Cytosporone B; 1 μM). The expression levels of the epithelial marker E-cadherin, the mesenchymal markers fibronectin (FN), vimentin, smooth muscle alpha-actin (α-SMA), and fibroblast-specific protein 1 (FSP-1), and the components of the transforming growth factor (TGF)-β pathway were detected by real-time polymerase chain reaction and western blotting. Compared with the control group, E-cadherin in the acetaldehyde group was downregulated, whereas FN, FSP-1, vimentin, α-SMA, and COL1A1/COL1A2 were upregulated (P < 0.05). Compared with the acetaldehyde group, NR4A1 agonist upregulated E-cadherin and downregulated FN, FSP-1, vimentin, α-SMA, and COL1A1/COL1A2 (P < 0.05). After acetaldehyde stimulation, TGF-β, Smad2/3/4, and zinc finger E-box-binding homeobox (ZEB) were upregulated, while Smad7 mRNA levels were downregulated (all P < 0.05). Compared with acetaldehyde alone, NR4A1 agonist increased Smad7 mRNA levels and reduced TGF-β, Smad2/3/4, and ZEB mRNA levels (all P < 0.05). NR4A1 activation suppresses acetaldehyde-induced EMT, as shown by epithelial and mesenchymal marker expression. The inhibition of the TGF-β–Smad2/3/4–ZEB signaling during HSC activation might be involved.

[Purpose/Significance] Exploring the influence factors of electronic word-of-mouth (eWOM) and user purchase behavior after the epidemic, so as to better attract users in the post-epidemic era, which is crucial for promoting the economic recovery of the online short-term rental industry. [Method/Process] This research obtained public data in Beijing area on Airbnb, and constructed a measurement index of eWOM based on BERT. Then based on the ELM, a model of influencing factors of online short-term rental users' purchase behavior was constructed with 4 listing attributes and 6 landlord attributes. Finally, the empirical research was carried out. [Result/Conclusion] Using the average sentiment score of reviews calculated by the BERT model to measure online short-term rental eWOM provided ideas for confirming its substitute variables.

The traditional thermodynamic equation based on heat flow balance without reflecting the variation characteristics of the reaction process. New thermodynamics equation based on energy conservation is established involving multiple complex factors with reaction process, including species, matter mass and heat capacity. The DSC/DTA equation acquired from energy differential equation. The new equation reflects the dynamic Kirchhoff's law and expresses the heat capacity including the integral term and the differential term which both decided by reaction progression. Two kinds of modes with CaCO3 reactions are carried out to verify the equation. The theoretical calculations are well in accord with the experimental data, which validates the accuracy and reliability of the new equation.Reaction process; Thermodynamic equation; DSC/DTA; Thermal capacity

[Purpose/Significance] The purpose is to explore the predetermined behavior of resource demanders based on the information generated from the perspective of multi-layer trust on the shared service platform, so as to facilitate the recovery and sustainable development of the sharing economy in the post-pandemic era.[Method/Process] Combined with the trust information of the supply and demand sides on the platform, between the supply and demand sides and the demand side on the shared products, based on the "3P+3I" theory from the perspective of multi-layer trust, a research model of consumer purchasing behavior of the shared service platform is constructed. Taking the shared short-term rental platform as an example, this paper obtained the public data of Airbnb in Beijing area, used Bert algorithm to construct the reputation index of housing products, and preliminary speculated the internal mechanism of user reservation behavior based on causal discovery algorithm in causal inference, and used Poisson regression to conduct empirical analysis.[Result/Conclusion] The trust variables of both parties to the platform, between the two parties and the demander to the shared product had a significant positive promoting effect on housing sales. The trust characteristics generate by hosts had the largest positive effect on tenants' booking behavior. It is suggested that hosts should make great efforts to establish the reputation of hosts and disclose more information appropriately. In order to obtain the badge of "super host", they can give priority to not providing "direct booking" service so as to screen out users who may have malicious comments. It is suggested that platforms strictly check the personal qualifications of users. More attention should be paid to improve the identity information authentication mechanism and comment incentive system for users, so as to reduce the uncertainty in users' decision-making.

Objective To identify risk factors of non-curative resection in superficial esophageal cancer (SEC) after endoscopic submucosal dissection and to evaluate the prognosis. Methods We retrospectively analyzed the data of 207 SEC patients who received ESD. The median follow-up was 48 months. Results The en bloc resection rate was 89.25% (191/214), the complete resection rate was 80.84 % (173/214), the curative resection rate was 70.09% (150/214) and the non-curative resection rate was 29.91% (64/214). The maximum long diameter of specimen was 110 mm. Age, gender, tumor size, lesions performance during surgery and operation time were associated with the non-curative resection (P < 0.05). Female, lesion diameter≥50mm and poorly performed lesions were identified as significant risk factors for non-curative resection. In the non-curative resection group, there was no difference in cancer-free survival and survival between patients who had no additional treatmeat after ESD and those who underwent surgery or radiotherapy. Conclusion For patients with poor general condition who are not willing to undergo surgery or chemoradiotherapy, regular endoscopy seems to be an option.

Objective To investigate the effects of endoscopic submucosal dissection (ESD) on rectal neuroendocrine tumor(RNET) and evaluate its safety. Methods We retrospectively analyzed the clinical data of 80 patients (91 lesions) diagnosed as RNET underwent rectal ESD from January 2011 to December 2017 in Jiangsu Provincial People's Hospital. All patients were followed up. Results All lesions were completely resected. Symptomatic patients had different degrees of relief from the 3rd days to 2 months after surgery. There was no serious postoperative complication. The positive rate of margin was 20.88% (19/91). The suspicious positive rate of margin was 35.16% (32/91). The maximum long diameter of specimen was 20 mm. Tumor size ≥10mm and Grade G2 were associated with suspicious positive and positive margin in univariate analysis(P < 0.05). Grade G2 was identified as independent risk factor in multivariate analysis (P < 0.05). Only one patient in this study was confirmed to be RNET preoperatively. Median follow-up was 34 months and the recurrence rate was 4.40% (4/91). Conclusion ESD is effective in the treatment of G1 and G2 grades RNET patients with tumor diameter < 20mm. For RNET patients with positive margin and suspicious positive margin after ESD, close follow-up without additional treatment seems to be a feasible option.

[Purpose/significance] At present, the popularity of "involution" has become a cultural phenomenon, and the social reality it reflects deserves attention. Clarify the concept and characteristics of "involution" and measure it from a quantitative perspective, which helps to quickly seek the formation mechanism of "involution" and the path to solve it. [Method/process] At first, the study explained the evolution of the concept of "involution". Secondly, the evaluation index of "involution" is constructed in relation to the competition scenario of university students. Finally, we analyzed the experimental results, and gave corresponding suggestions from the three dimensions of individual and group. [Result/conclusion] As the randomness in the network topology decreases, the degree of competition for the "involution" of the system increases. The cooperative strategy can improve the total output of the system, while the total system input of the competitive strategy is high, but the total output of the system is low. On the whole, the value evaluation under the global mode is outstanding in the characteristics of high investment, low return and diminishing marginal utility, and the "involution" is serious.

Aiming at the problem of IC card theft in the society, an IC card security defense system based on outlier detection is designed. The system collects the physical layer and application layer information of the IC card through RFID terminal and transmits the data to the cloud server. The cloud server uses the outlier detection algorithm based on integrated learning to process the data. If the IC card is abnormal, it prompts the user through the mobile APP. The test result shows that the accuracy of magnetic field signal anomaly detection sub-classifier and user habit anomaly detection sub-classifier is 0.95 and 0.65 respectively, indicating that the system can identify the pseudo card through effectively detecting the abnormal state of the IC card.

In order to solve the problem that current avoidance method of shipwreck has the problem of low success rate of avoidance, this paper proposes a method of intelligent avoidance of shipwreck based on big data analysis. Firstly,our method used big data analysis to calculate the safe distance of approach of ship under the head-on situation, the crossing situation and the overtaking situation.On this basis, by calculating the risk-degree of collision of ships,our research determined the degree of immediate danger of ships.Finally, we calculated the three kinds of evaluation function of ship navigation, and used genetic algorithm to realize the intelligent avoidance of shipwreck.Experimental result shows that compared the proposed method with the traditional method in two in a recent meeting when the distance to closest point of approach between two ships is 0.13nmile, they can effectively evade.The success rate of avoidance is high.