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To solve the problem of poor stability of additive flame retardant waterborne polyurethane， a series of waterborne polyurethane with flame retardant properties was synthesized by prepolymer method using aliphatic polyisocyanate， polyether polyol， and flame retardant phosphorus-containing polyol as raw materials. The flame retardant waterborne polyurethane was applied to the dipping process of microfiber synthetic leather base （microfiber base）. Its effects on the mechanics， quality， flame retardant， and thermal decomposition properties of microfiber base were discussed. The results show that with the increase of phosphorus-containing flame retardant polyol content， the combustion rate decreases from 115.00 mm/min to 60.79 mm/min， and the limiting oxygen index increases from 21.00% to 24.20%. After different concentrations of phosphorus-nitrogen flame retardants were sprayed on the surface of microfiber base， microfiber base appears self-extinguishing phenomenon during combustion， and the limiting oxygen index increases to 27.00%. Compared with the microfiber base without flame retardant treatment，the peak heat release rate and total heat release rate of the microfiber base after flame retardant treatment are reduced by 42.29% and 20.01%， respectively. The test analyses of SEM and Raman spectroscopy reveal that the graphitization degree of the carbon layer is improved and the surface structure becomes more compact after flame retardant finishing， suggesting that the flame retardant plays a crucial role by using the condensed phase flame retardant mechanism.

Background Coronary heart disease (CHD) is one of the major public health burdens in the world. Although treatment strategies have been developed, but CHD remains a leading cause of morbidity and mortality worldwide. The diagnosis of CHD mainly relies on coronary angiography or contrast-enhanced computed tomography. However, due to the lack of equipment in primary hospitals, early diagnosis and prognosis judgment are relatively difficult. Therefore, the search for relatively simple and easy-to-obtain laboratory indicators is conducive to providing basis for primary care physicians to diagnose and treat CHD. Objective To investigate the correlation of serum interleukin-6 (IL-6) and fasting blood glucose (FPG) levels with the degree and clinical classification of coronary stenosis, number of lesions and adverse cardiovascular events in patients with CHD. Methods CHD patients admitted to the Fifth Affiliated Hospital of Xinjiang Medical University from September to November 2020 were included as the study objects, and their general data and laboratory test results were collected. According to Gensini score criteria, the patients were divided into the mild stenosis group (group A, Gensini score≤33.25 points, n=40) and moderate and severe stenosis group (group B, Gensini score>33.25 points, n=40) based on the Gensini scoring criteria. According to the results of coronary angiography results, patients were divided into the single-vessel lesion group (n=28), double-vessel lesion group (n=21) and multi-vessel lesion group (number of lesion branch≥3, n=31) based on the number of lesions. According to the clinical classification, patients were divided into stable angina group (n=34) and acute coronary syndrome group (n=46). Spearman rank correlation analysis was used to explore the relationship of serum IL-6, FPG with relevant data of patients. Survival curves of patients were plotted using the Kaplan-Meier method, and the comparison of survival curves was performed by Log-rank test. Univariate and multivariate Cox proportional hazard regression analyses were used to explore the factors influencing the risk of adverse cardiovascular events in patients with CHD. The receiver operating characteristic (ROC) curve of IL-6 predicting the occurrence of adverse events was plotted. Results IL-6 and FPG in group A were lower than those in group B, IL-6 in the multi-vessel lesion group was higher than that in the single-vessel lesion group, FPG was higher than that in double-vessel lesion group, and IL-6 and FPG in acute coronary syndrome group was higher than that in stable angina group, with statistical significance (P45.8 ng/L group (n=39) and IL-6≤45.8 ng/L group (n=41) according to the median IL-6 expression level (45.8 ng/L), and the upper limit of normal FPG (6.1 mmol/L) was used as the grouping standard to divide the patients into FPG>6.1 mmol/L group (n=36) and FPG≤6.1 mmol/L group (n=44). Log-rank test results showed that the incidence of adverse cardiovascular events in IL-6>45.8 ng/L group was higher than that in IL-6≤45.8 ng/L group (76.9% vs. 36.6%; χ2=16.075, P < 0.001), FPG>6.1 mmol/L group had a higher incidence of adverse cardiovascular events than FPG≤6.1 mmol/L group (69.4% vs. 45.5%; χ2=4.292, P=0.038). Multivariate Cox proportional hazard regression analysis showed that IL-6 was a significant factor in adverse cardiovascular events in patients with CHD (HR=2.396, 95%CI=1.203-6.054, P

Oxygen and nutrient deprivation are common features of solid tumors. Although abnormal alternative splicing (AS) has been found to be an important driving force in tumor pathogenesis and progression, the regulatory mechanisms of AS that underly the adaptation of cancer cells to harsh microenvironments remain unclear. Here, we found that hypoxia- and nutrient deprivation-induced asparagine endopeptidase (AEP) specifically cleaved DDX3X in a HIF1A-dependent manner. This cleavage yields truncated carboxyl-terminal DDX3X (tDDX3X-C), which translocates and aggregates in the nucleus. Unlike intact DDX3X, nuclear tDDX3X-C complexes with an array of splicing factors and induces AS events of many premRNAs; for example, enhanced exon skipping (ES) in exon 2 of the classic tumor suppressor PRDM2 leads to a frameshift mutation of PRDM2. Intriguingly, the isoform ARRB1-[DELTA]exon 13 binds to glycolytic enzymes and regulates glycolysis. By utilizing in vitro assays, glioblastoma organoids, and animal models, we revealed that AEP/tDDX3X-C promoted tumor malignancy via these isoforms. More importantly, high AEP/tDDX3X-C/ARRB1- [DELTA]exon 13 in cancerous tissues was tightly associated with poor patient prognosis. Overall, our discovery of the effect of AEP-cleaved DDX3X switching on alternative RNA splicing events identifies a mechanism in which cancer cells adapt to oxygen and nutrient shortages and provides potential diagnostic and/or therapeutic targets., Introduction In the tumor microenvironment, cells often face a certain degree of oxygen and nutrient deprivation. Cancer cells strive to survive and proliferate in this harsh environment in multiple ways, [...]

The effects of different preparation techniques (aqueous enzymatic extraction, aqueous extraction, cold pressing, hot pressing and organic solvent extraction) on the physical and chemical properties, nutritional components and oxidation stability of tiger nut oil from the cultivar ‘Zhongyousha 1’ grown in Xinjiang were investigated. The results showed that organic solvent extraction gave the highest extraction rate (88.31%), and there were significant differences in the physicochemical properties of tiger nut oils prepared by different processes (P < 0.05). Oleic acid accounted for 76.04% of the total fatty acids in the oil prepared by aqueous extraction, which was 1.72–2.34 percentage points higher than that obtained with other preparation processes (P < 0.05). Different preparation techniques had significant effects on the lipid concomitant content and oxidation stability of tiger nut oil (P < 0.05). The oil obtained by organic solvent extraction had the highest contents of tocopherol (370.67 mg/kg), total phenol (168.59 mg/100 g) and phytosterol (271.26 mg/100 g), while the content of squalene was highest (162.04 mg/kg) in the oil obtained by aqueous extraction. The cold pressed oil had the highest oxidation stability index (24.15 h) indicating good oxidation stability. Correlation analysis indicated that the oxidation stability of tiger nut oil was positively correlated with unsaturated fatty acid and oleic acid (r = 0.72, r = 0.48), and the antioxidant capacity (1,1-diphenyl-2-picrylhydrazyl and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radical scavenging rate) of polar components was significantly positively correlated with total phenol content (r = 0.91, r = 0.96, P < 0.05). The results of principal component analysis (PCA) revealed that the cold pressed oil was similar to the oil obtained aqueous enzymatic extraction, while the oils prepared by organic solvent extraction, hot pressing and aqueous extraction were differentiated well. These results can provide a theoretical basis for the development of high-quality tiger nut oil.

Vision-based laser penetration control has become an important research area in the field of welding quality control. Due to the complexity and large number of parameters in the monitoring model, control of the welding process based on deep learning and the reliance on long-term information for penetration identification are challenges. In this study, a penetration recognition method based on a two-stage temporal convolutional network is proposed to realize the online process control of laser welding. In this paper, a coaxial vision welding monitoring system is built. A lightweight segmentation model, based on channel pruning, is proposed to extract the key features of the molten pool and the keyhole from the clear molten pool keyhole image. Using these molten pool and keyhole features, a temporal convolutional network based on attention mechanism is established. The recognition method can effectively predict the laser welding penetration state, which depends on long-term information. In addition, the penetration identification experiment and closed-loop control experiment of unequal thickness plates are designed. The proposed method in this study has an accuracy of 98.96% and an average inference speed of 20.4 ms. The experimental results demonstrate that the proposed method exhibits significant performance in recognizing the penetration state from long sequences of welding image signals, adjusting welding power, and stabilizing welding quality. [ABSTRACT FROM AUTHOR]

Incorporating metal cations into V2O5 has been proven to be an effective method for solving the poor long-term cycling performance of vanadium-based oxides as electrodes for mono- or multivalent aqueous rechargeable batteries. This is due to the existence of a bilayer structure with a large interlayer space in the V2O5 electrode and to the fact that the intercalated ions act as pillars to support the layered structure and facilitate the diffusion of charged carriers. However, a fundamental understanding of the mechanical stability of multi-ion-co-intercalated bilayered V2O5 is still lacking. In this paper, a variety of pillared vanadium pentoxides with two types of co-intercalated ions were studied. The root-mean-square deviation of the V-O bonds and the elastic constants calculated by density functional theory were used as references to evaluate the stability of the intercalated compounds. The d-band center and electronic band structures are also discussed. Our theoretical results show that the structural characteristics and stability of the system are quite strongly influenced by the intercalating strategy. [ABSTRACT FROM AUTHOR]

In the construction of urban underground shield tunnels, uneven deformation can easily occur when the shield passes through soft soil and other poor strata. Such deformation has a significant impact on surface settlement and may cause potential safety hazards to the surrounding existing buildings, directly affecting the safety of urban operation. When simulating and predicting surface settlements, the small-strain soil hardening model can more accurately characterize the mechanical parameters of soil. Nevertheless, its parameters are numerous and complicated to determine accurately, so parameter inversion is needed to determine the accurate parameters of the soft soil layer in order to more accurately predict the surface settlement. This study uses the EFAST method to analyse the sensitivity of the HSS model parameters of soft soil strata. It is determined that the parameters that have the most significant impact on the surface settlement are the reference tangent modulus, rebound modulus, and effective cohesion. Then, XGBoost's fast calculation speed and high precision of SSA inversion are used to inverse and optimize the parameters with high sensitivity. Finally, according to the parameters of the soft soil layer obtained from inversion and measured data, the settlement deformation and safety behaviour of existing buildings are analysed. Combined with the actual shield tunnel project in a city along a river, the inversion calculation shows that the overall average error of the transverse monitoring section is 1.04 mm, and the average maximum error of each monitoring point in the overall shield process is 2.87 mm. The prediction effect is significantly improved compared with the original parameters. The accuracy of the inversion of soil layer parameters is verified from the perspective of time and space. The average settlement of the river embankment foundation is 2.5 mm. Compared with the original parameter data, the prediction results have been greatly improved, and the settlement deformation results are more consistent with the measured data. [ABSTRACT FROM AUTHOR]

To establish a safety monitoring method for the uplift pressure of concrete dams, spatiotemporal information from monitoring data is needed. In the present study, the method of ordering points to identify the clustering structure is employed to spatially cluster the uplift pressure measuring points at different locations on the dam; three distance indexes and two clustering evaluation indexes are used to realize clustering optimization and select the optimal clustering results. The Bayesian panel vector autoregressive model is used to establish the uplift stress safety monitoring model for each category of monitoring point. For a nonstationary sequence, the difference method is selected to ensure that the sequence is stable, and the prediction is carried out according to the presence or absence of exogenous variables. The result is that the addition of exogenous variables increases the accuracy of the model's forecast. Engineering examples show that the uplift pressure measurement points on the dam are divided into seven categories, and classification is based mainly on location and influencing factors. The multiple correlation coefficients of the training set and test set data of the BPVAR model are more than 0.80, and the prediction error of the validation set is lower than that of the Back Propagation neural network, XGBoost algorithm, and Support Vector Machines. The research in this paper provides some reference for seepage monitoring of concrete dams. [ABSTRACT FROM AUTHOR]

Rockfalls are major geological hazards threatening prestressed concrete cylinder pipes (PCCPs) in water diversion projects. To accurately assess the impact of large deformation movements of rockfalls on PCCPs, this study utilized the continuous–discontinuous method to investigate the dynamic response of a PCCP under a rockfall. The impact mode of rockfalls, the mechanical characteristics of PCCP, and the nonlinear-contact characteristics between soil and PCCP were considered in this study. The advantages of continuous and discontinuous numerical simulation methods were utilized to establish a continuous and discontinuous coupling model of "tube-soil-rock" considering the interaction of soil and structure. The impact mechanism and process of PCCP under the rockfall were investigated by simulating the rockfall process and analyzing its spatiotemporal evolution. The influence of PCCP under rockfalls with different heights and radii was studied to clarify the effects of these two parameters on the PCCP. Combined with a practical application example of large-scale water transfer projects, there is a tendency of center flattening under static load and dynamic impact load, and the PCCP part directly below the impact point is the most dangerous. This investigation provided a comprehensive understanding of the impact mechanism of the PCCPs under rockfall. The findings of this study have significant implications for the design of the protection engineering of PCCPs and ensuring the safe operation of water diversion projects. [ABSTRACT FROM AUTHOR]