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Objective: In this experiment, polysaccharides from cortex periplocae (CPP) were isolated and purified, and their monosaccharide composition and antioxidant activity were investigated, so as to provide a reference for the development and application of CPP in the food industry. Methods: The crude polysaccharides were obtained by aqueous extraction, alcoholic precipitation and protein removal by Sevag method, and four polysaccharide fractions CPP0, CPP1, CPP2 and CPP3 were separated and purified by DEAE-52 cellulose column. The chemical composition, molecular weight, monosaccharide composition, infrared spectrum and antioxidant activity were analyzed. Results: The sugar contents of these four polysaccharides were 82.20%, 77.13%, 75.23% and 72.85%, respectively, and all of them contained glyoxylate. The relative molecular weights were 685, 477, 411 and 572 kDa, respectively. The four polysaccharides were all heteropolysaccharides composed of mannose, rhamnose, galacturonic acid, glucose, galactose and arabinose in different molar ratios. The infrared spectra showed that four polysaccharides contained β-glycosidic bonds and with furan rings. The antioxidant experiments showed that all four polysaccharides had certain antioxidant properties, and the overall antioxidant capacity was in the following order: CPP0>CPP3>CPP1>CPP2. Conclusion: The four acidic polysaccharides extracted from cortex periplocae have high sugar content, high relative molecular weight, and antioxidant activity, among which CPP0 fraction has the best antioxidant activity.

Sea water intrusion is an important environmental issue that plagues the economic and social development in coastal areas. The implementation of quantitative simulation, prediction and visual management of sea water intrusion is a cost-effective means for monitoring and mechanism analysis of sea water intrusion, which can provide important theoretical and technical supports for the formulation of sea water intrusion control measures. VFT3D was proposed to model the sea water intrusion processes and predict the impacts on groundwater, which can comprehensively consider the effects of surface water and groundwater, simulate variable-density groundwater flow, and solve complex reactive migration problems. This article provides an introduction to the VFT3D model and presents an application of VFT3D to modeling seawater intrusion process. The simulated results are compared with those of the SEAWAT. The results show that the simulated water heads with VFT3D are close to the SEAWAT simulation results. The SEAWAT is unable to simulate complex chemical reactions during the sea water intrusion. The results indicate that geochemical processes (cation adsorption and exchange) have a significant effect on the movement of cations (Na+, K+, Mg2+ and Ca2+). Geochemical process leads to the concentration change in the transition zone, whose influence on the process of sea water intrusion can not be ignored. Therefore, the variable density and complex reaction process should be involved to more accurately describe the sea water intrusion, which can benefit the implementation of the underground saltwater remediation and management.

Objective:To observe the effect of extracorporeal shock wave combined with occupational therapy therapy on forearm pronation disorder in children with spastic cerebral palsy(SCP).Methods:A total of 42 children with SCP were randomly divided into the control group and the observation group, with 21 cases in each group in the children rehabilitation department of the affiliated Nanhai maternity and children's Hospital of Guangzhou university of traditional Chinese medicine from January to December 2019.The control group was given targeted occupational therapy, including upper limb forearm pronator stretching therapy, neurophysiological therapy(Bobath technology), proprioceptive neuromuscular facilitation therapy(PNF); game type occupational training including placing objects in forearm supination position, supination grasping stick, supination fetching game, palm and back game, etc..The above training was conducted once a day, 30 minutes per time, six times a week, three months as a course of treatment, continuous treatment for two courses.The observation group was given extracorporeal shock wave therapy on the basis of the control group.The child with SCP was in a comfortable position and the forearms of the upper limbs were placed on the plane so that it could free its own gravity.The abdomen of pronator teres muscle was impacted with the probe of shock wave therapeutic instrument(pressure intensity: 1.0-1.5 bar;frequency: 8-10 Hz;impact times: 1 000-2 000 times).Three to five minutes each time, once every three days, twice a week, three months as a course of treatment, continuous treatment for two courses.Before treatment, after treatment for three months and six months, the modified Ashworth scale(MAS)was used to evaluate the spasticity of forearm pronator muscles;the active range of motion(AROM)of forearm supination was measured by joint range of motion protractor;and the fine motor quotient(FMQ)of hands was evaluated by Peabody development motor scale-fine motor(PDMS-FM).Results:Before treatment, there was no significant difference in MAS score, AROM angle and FMQ score between two groups(P>0.05).Compared with before treatment, the MAS scores of the two groups decreased significantly after treatment for three and six months, and the AROM angle and FMQ score increased significantly, the difference was statistically significant(PP

The existence of non-line-of-sight (NLOS) error can degrade the positioning performance in wireless sensor network localization system,especially in indoor localization.To overcome the localization error caused by NLOS propagation,a localization algorithm was proposed based on received signal strength (RSS) and time-of-arrival (TOA).Firstly,a non-convex optimization problem was established based on RSS and TOA.Then,the original non-convex optimization problem was transformed into a convex optimization problem through the second-order cone relaxation technique,therefore a sub-optimal solution to the original problem could be obtained efficiently.Finally,computer simulation results show that the proposed method can provide higher estimation accuracy and better performance.

Background and objective The tyrosine kinase inhibitors (TKI) treatment of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation may have a positive effect, but most patients may develop drug resistance, therefore, the detection of the developing time in drug resistance and the research of the mechanism of drug resistance are need to be solved. While the emerge of next generation sequencing (NGS) have make it possible. The aim of this study is to monitor the efficacy of targeted therapy by studying the variation of circulating tumor DNA (ctDNA) mutation frequency and gene mutation spectrum through the targeted therapy. Methods Our center enrolled 22 patients with EGFR mutation detected by tissue or peripheral blood, and collect 8 mL of peripheral blood of the patients for ctDNA sequencing in different phases, before systematic prior treatment, followed-up by 2 months and disease progression after TKI administration. Results Patients with EGFR gene mutation may acquire a longer median survival time after receiving targeted drug therapy, due to the drop of mutation abundances, while the therapy may have a minor effect in patients which their mutation abundances have slightly decreased compared to the statistics before the cession (P=0.015,3). The significantly reduced group median progression was associated with a longer survival [progression free survival (PFS)=390 d]. At the same time, we found out that when related to TP-53 gene mutation, the effect of targeted drug therapy for EGFR-sensitive mutation was unsatisfactory (the median PFS was 120 d compared with 630 d, P=0.000,2). Conclusion Patients who has lower mutation abundance with EGFR sensitive mutations after TKI treatment may have a longer survival period (P

Focusing on the impulsive noise mitigation in underwater acoustic communication,an impulsive noise mitigation method based on iteration adaptive approach was proposed.Firstly,by utilizing the orthogonality of the subcarriers in OFDM system,both the impulsive noise and background noise were separated from the signals.Then null tones matrix was used to construct a steering matrix and get the impulsive noise interference covariance matrix.Furthermore,a cost function based on weighted least squares approach was proposed and a close form expression for the impulsive noise was derived.Finally,the impulsive noise was mitigated by substracting the estimation of the impulse noise in the received signal.Simulation results show that the proposed algorithm can reduce the bit error rate (BER) efficiently and provide better performance,especially in high signal to impulsive noise ratio (SINR) case.

Anti-vibration rubber, because of its superior elasticity, plasticity, waterproof and trapping characteristics, is widely used in the automotive industry, national defense, construction and other fields. The theory and technology of predicting fatigue life is of great significance to improve the durability design and manufacturing of anti-vibration rubber products. According to the characteristics of the anti-vibration rubber products in service, the technical difficulties for analyzing fatigue properties of anti-vibration rubber materials are pointed out. The research progress of the fatigue properties of rubber materials is reviewed from three angles including methods of fatigue crack initiation, fatigue crack propagation and fatigue damage accumulation. It is put forward that some nonlinear characteristics of rubber under fatigue loading, including the Mullins effect, permanent deformation and cyclic stress softening, should be considered in the further study of rubber materials. Meanwhile, it is indicated that the fatigue damage accumulation method based on continuum damage mechanics might be more appropriate to solve fatigue damage and life prediction problems for complex rubber materials and structures under fatigue loading.

Background and objective Epidermal growth factor receptor (EGFR) overexpression and mutations were existed in more than 40% of the lung cancer, and it’s the one of molecular targets in clinical treatment. But the EGFR tyrosine kinase inhibitors (TKI)-resistance is becoming a challenging clinical problem as following the application of EGFR-TKIs, Gefitinib or Erlotinib. However, the mechanistic explanation for resistance in the some cases is still lacking. Here we researched the resistance mechanism of H1650 cells. Methods Using real-time RT-PCR to analyze the EGFR mRNA expression level in EGFR wild-type non-small cell lung cancer (NSCLC) cells; MTT analysis detected the cytotoxicity for NSCLC cells to Erlotinib; Western blot analysis examined the mutant situations and the downstream signaling protein phosphorylation level in EGFR-mutant NSCLC cells with the treatment of Erlotinib or/and PI3K inhibitor, LY294002. Results In the EGFR wild-type NSCLC cells, the expression level of EGFR mRNA varied dramatically and all the cells showed resistant to Erlotinib; In the EGFR-mutant cells, HCC827 and H1650 (the same activating-mutation type), HCC827 cells were Erlotinib-sensitive as well as H1650 demonstrated primary relative resistance. Western blot analysis showed the loss of PTEN and the p-AKT level was not inhibited with the treatment of Erlotinib or/and LY294002 in H1650 cells, while HCC827 cells were no PTEN loss and definitively decrease of p-AKT level. Conclusion EGFR wild-type NSCLC cells were resistant to Erlotinib no matter of how EGFR mRNA expression level. EGFR-activating mutations correlated with responses to Erlotinib. The PTEN loss and activation of AKT signaling pathway contributed to Erlotinib resistance in EGFR-mutant NSCLC cell line H1650.

Informal institutions, like traditions, customs and habits, play an important role in the process of socioeconomic development. In some cases, informal institutions even shape the formal institutions. As China’s special marriage customs, uxorilocality, exchange marriage, children marriage and raising daughter-in-law marriage are all informal institutional arrangements. They could save transaction costs, shorten proxy chains, and maintain a marriage market equilibrium, which are all important parts of the institution of marriage in China. [ABSTRACT FROM AUTHOR]

The classification of the defects in welding applications based on the metallographic structure images plays an important part in industrial welding quality inspections. In order to improve the classification performance of defects in the weld metallographic structure images with a small sample dataset available (the amount of samples being less than 30), a Poisson fusion method is used for data augmentation of the defect images and the ResNet18_PRO network is proposed. Both of the methods notably improve the defects classification performance. During data augmentation, the defect area is extracted from original defect samples via digital image processing, and the defect area is fused with normal samples by the Poisson fusion method to generate new defect samples, thus increasing the number of defect samples. The model in this paper is improved based on the ResNet18 network. The downsampling structure is improved to reduce the information loss in the original downsampling structure, and an improved space pyramid pooling structure is added at the end of the network to integrate multi-scale feature information. The classification performance before and after data augmentation is compared by different classification models, which verifies the significant effect of the data augmentation on the classification performance. Meanwhile, the ablation experiment of the ResNet18_PRO is conducted to verify the effectiveness of the improved network structure and the training strategy. It is found that the average classification accuracy of ResNet18_PRO reaches 98.83% and the average F1-score reaches 98.76%, which greatly improves the classification accuracy of metallographic structure defects. Finally, the network is trained and tested with another industrial defect dataset and obtains good classification results. These results show that the proposed network has a good robustness and practical application value.

Objective To investigate the protective effect of remimazolam on cerebral nerves in a rat model of cerebral ischemia/reperfusion injury and its mechanism. Methods A total of 50 male Sprague-Dawley rats were randomly divided into sham-operation group (Sham group), cerebral ischemia/reperfusion group (I/R group), I/R+remimazolam (RE) group, I/R+RE+LY294002 (LY) group, and I/R+LY group. Neurological deficit score was used to evaluate the degree of neurological dysfunction. After arterial blood samples and brain tissue pathological sections were collected from the rats in each group, 2,3,5-trip-henyltetrazolium chloride staining was performed for the brain tissue sections to calculate cerebral infarct volume ratio; ELISA was used to measure the serum levels of interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α); Western blotting was used to measure the relative expression levels of protein kinase B (AKT), phosphorylated AKT (p-AKT), nuclear factor-kappa B p65 (NF-κB p65), and phosphorylated NF-κB p65 (p-NF-κB p65) in brain tissue, and then immunofluorescence assay was used to measure the expression level of p-NF-κB p65 inside and outside the nucleus of cells in brain tissue. Results There were significant differences between these groups in cerebral infarct volume ratio, neurological deficit score, the serum levels of IL-6, IL-1β, and TNF-α, the relative expression levels of p-AKT and p-NF-κB p65, p-AKT/AKT ratio, and p-NF-κB p65/NF-κB p65 ratio (F=72.41-654.90,P