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In recent years, our country's transmission lines have often been in danger due to geological disasters such as landslides when passing through fragile geological environments, which has brought great challenges and risks to the operation and maintenance of transmission lines. In order to understand the impact of transmission line towers on tower foundation slopes under heavy rainfall conditions, the influence of towers at different locations, rainfall intensities, and slopes on slope stability was analyzed by using Geo-Studio finite element analysis software. The results show that the slope has an important influence on the selection of the reasonable position of the tower. When the tower is located at the lower part of the slope, the safety factor of the slope is the highest. The safety factor of the slope is also reduced, and eventually the slope will be unstable and destroyed; the stability coefficient of the slope in the natural state is 1.221, which is in a stable state. Slopes are prone to overall sliding, with the spoil and overburden as the sliding body and the rock–soil contact surface as the sliding surface. This result provides a scientific basis for further understanding the influence mechanism of the slope angle at the location of the tower pole on this type of landslide under rainfall conditions. Further research can use the results of this paper as a benchmark to carry out corresponding experimental analysis and verification work. [ABSTRACT FROM AUTHOR]

Seamless flatness rollers are the core equipment for cold-rolled strip flatness detection. The change in wear resistance of the roller surface-strengthened layer has important guiding significance for the prediction of the roller surface life. The experimental results of the five rounds of friction and wear testing show that the volume–wear rate of the original roller surface is only 1.85 × 10−6 mm3 (N·M)−1. After the first grinding, the wear resistance of the roller surface decreased and the wear rate was approximately 2.76 × 10−6 mm3 (N·M)−1. After the second grinding, the wear morphology, wear rate and wear resistance of the samples in each round showed little difference. The average wear rate in the last three rounds of the test is 3.56 × 10−6 mm3 (N·M)−1 and the wear resistance is significantly lower than that of the previous two rounds of the test. The calculation shows that the original surface wear resistance is 32.92% higher than that of the surface after the first grinding, and the average wear resistance of the surface after the first grinding is 22.59% higher than that of the surface after the second, third and fourth grinding. With long-term use and repeated grinding repair, the roller surface will show a trend of wear resistance decline. When the wear resistance decreases to a certain degree, it will reach a stage of stability. These phenomena provide regular and quantitative references for the study of the life prediction of flatness meter rollers. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to establish an N6-methylandenosine (m6A)-related long non-coding RNA (lncRNA) signature to predict the prognosis of hepatocellular carcinoma (HCC). Methods: Pearson correlation analysis was used to identify m6A-related lncRNAs. We then performed univariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) Cox regression analysis to construct an m6A-related lncRNA signature. Based on the cutoff value of the risk score determined by the X-title software, we divided the HCC patients into high -and low-risk groups. A time-dependent ROC curve was used to evaluate the predictive value of the model. Finally, we constructed a nomogram based on the m6A-related lncRNA signature. Results: ZEB1-AS1, MIR210HG, BACE1-AS, and SNHG3 were identified to comprise an m6A-related lncRNA signature. These four lncRNAs were upregulated in HCC tissues compared to normal tissues. The prognosis of patients with HCC in the low-risk group was significantly longer than that in the high-risk group. The M6A-related lncRNA signature was significantly associated with clinicopathological features and was established as a risk factor for the prognosis of patients with HCC. The nomogram based on the m6A-related lncRNA signature had a good distinguishing ability and consistency. Conclusion: We identified an m6A-related lncRNA signature and constructed a nomogram model to evaluate the prognosis of patients with HCC. [ABSTRACT FROM AUTHOR]

Purpose: To unravel the oncogenic role of CDCA4 in different cancers from the perspective of tumor immunity. Methods: Raw data on CDCA4 expression in tumor samples and paracancerous samples were obtained from TCGA and GTEX databases. In addition, we investigated pathological stages and the survival analysis of CDCA4 in pan-cancer across Gene Expression Profiling Interactive Analysis (GEPIA) database. Cox Proportional Hazards Model shows that high CDCA4 levels are associated with several vital indicators in oncology. On the one hand, we explored the correlation between CADA4 expression and tumor immune infiltration by the TIMER tool; On the other hand, we utilized the methods of CIBERSORT and ESTIMATE computational to evaluate the proportion of tumor infiltrating immune cells (TIIC) and the amounts of stromal and immune components based on TCGA database. The use of antineoplastic drugs and the expression of CDCA4 also showed a high correlation via linear regression. Protein–Protein Interaction analysis was performed in the GeneMANIA database, and enrichment analysis was performed and predicted signaling pathways were identified by using Gene Ontology and Kyoto Encyclopedia of Genes. The correlation between CDCA4 expression with Copy number variations (CNV) and methylation is detailed, respectively. Molecular biology experiments including Western blotting, flow cytometry, EDU staining, Transwell and Wound Healing assay to validate the cancer promoting role of CDCA4 in hepatocellular carcinoma (HCC). Results: Most tumors highly expressed CDCA4. Elevated CDCA4 expression was associated with poor OS and DFS. There was a significant correlation between CDCA4 expression and TITCs. Moreover, markers of TIICs exhibited distinct patterns of CDCA4 associated immune infiltration. In addition, we pay attention to the association between the expression of CDCA4 and the use of the anti-tumor drugs. CDCA4 is related to biological progress (BP), cellular component (CC) and molecular function (MF). Dopaminergic Synapse, AMPK, Sphingolipid, Chagas Disease, mRNA Surveillance were significantly enriched pathways in positive and negative correlation genes with CDCA4. CNV is thought to be a positive correlation with CDCA4 expression. Conversely, methylation is negative correlation with CDCA4 expression. Molecular biology experiments confirm a cancer promoting role for CDCA4 in HCC Conclusion: CDCA4 may serve as a biomarker for cancer immunologic infiltration and poor prognosis, providing a new way of thinking for cancer treatment. [ABSTRACT FROM AUTHOR]

In order to break through the bottleneck of anionic polymerization, polar monomers such as methyl methacrylate (MMA), ethyl methacrylate, butyl methacrylate, and hexyl methacrylate are subjected to anionic polymerization at room temperature in tetrahydrofuran (THF) using potassium tert‐butoxide (t‐BuOK) as the initiator. The polymerization of alkyl methacrylates is studied by multidetector gel permeation chromatography, proton nuclear magnetic resonance (1H‐NMR) and 13C‐NMR spectroscopy, and dynamic laser light scattering. It is found that t‐BuOK can initiate the living anionic polymerization of polar alkyl methacrylate, and the polymerization conversion almost reaches up to 100%. t‐BuOK exists into two kinds of agglomerates, whose hydrodynamic volumes are 10 and 80 nm, respectively. t‐BuOK in THF is similar to emulsion and has a critical active species concentration of about 0.0265 mol L−1 and does not depend on how much t‐BuOK is added. After the initiation of the polymerization, the large agglomerates of a loose and less regular structure that have occupied the main part of t‐BuOK are greatly reduced, but they do not continue to decrease until they disappear according to the equilibrium theory. Similarly, the active chain after initiation also will not aggregate again. Furthermore, t‐BuOK also has an active species with smaller average vibration size between cation and anion pairs, which can only initiate the polymerization of MMA with rather slow rate but cannot initiate other alkyl methacrylates. At last, because t‐BuOK can make the dormant species caused by side reactions to be revived, the anionic polymerization of MMA could obtain a high yield. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1130–1139 [ABSTRACT FROM AUTHOR]

Borrelia burgdorferi as a causative agent of Lyme disease is transmitted by Ixodes spp. ticks to humans and animals. Sheep is considered a natural reservoir for B. burgdorferi and plays a pivotal role in disease transmission and the expansion of natural foci. An epidemiological investigation of B. burgdorferi in sheep is essential for prevention and control of Lyme disease. In this study, we developed a recombinant outer surface protein C (OspC)-based ELISA for serological study of B. burgdorferi in sheep with a specificity and sensitivity of 84.4% and 86.2%, respectively. A total of 972 collected serum samples from the Northeast China regions in 2015 and 2016 were determined with positive rates of 5.8% and 12.2%, respectively. Thus, specific pathogen-free sheep were infected with B. burgdorferi SZ strain to study on the secretion of specificity antibody against OspC. It revealed that specific antibody was detected on day 5 postinoculation and sustained in a high level for ∼28 days, the peak occurred at ∼13 days. Taken together, the result indicated that the established ELISA is capable for clinical diagnosis and epidemiological study on B. burgdorferi in sheep at the early stage of infection and detecting the specific antibody during the secretion period. [ABSTRACT FROM AUTHOR]

Initiating Mechanism of the Anionic Polymerization of Methacrylates with t-BuOK and the Synthesis of ABA Type Triblock Copolymers B Back Cover b : In article number 1900390, Anna Zheng, Yong Guan, and co-workers report that using I t i -BuOK as initiator, an ABA-type triblock copolymer (PMMA-b-PLMA-b-PMMA) is synthesized at 0 °C without using any sidereaction inhibitors and the monomer conversion is over 97%, which paves the way for the synthesis of thermoplastic elastomers with full polar monomers and full saturated chains by anionic polymerization. [Extracted from the article]

Abstract: It still remains a concern to break through the bottlenecks of anionic polymerization of polar monomers, such as side reactions, low conversion and low temperature (–78°C). In this work, potassium tert‐butoxide (t‐BuOK) was chosen to initiate the anionic polymerization of 2‐ethylhexyl methacrylate (EHMA) in tetrahydrofuran. The conversions were above 99% at 0 or 30°C, and above 95% at 60°C without side reaction inhibitors. The high conversions implied t‐BuOK could suppress the side reactions. A series of block copolymers of EHMA, n‐hexyl methacrylate (HMA) and methyl methacrylate (MMA) were further synthesized at 0°C, and the conversions were all above 99%. The GPC and 1H NMR results confirmed the successful synthesis of the block copolymers. The molecular size of monomer and the state of t‐BuOK (free ion pairs or aggregates) remarkably affected the polymerization rates and the molecular structures of the products. The DMA results indicated that the glass transition temperatures of PEHMA or PHMA block and PMMA block were 20°C and 60°C, respectively, which deviated from –2°C and 105°C of homopolymer, respectively, due to the partial compatibility of the blocks. This work explored a route of the anionic polymerization of polar monomers at room temperature. [ABSTRACT FROM AUTHOR]