Temperature is one of the important loads for designing slab track. The characteristic of slab track tem- perature varies greatly with different regional climates. In this work, a bi-block slab track model was built u...Temperature is one of the important loads for designing slab track. The characteristic of slab track tem- perature varies greatly with different regional climates. In this work, a bi-block slab track model was built under outdoor conditions in Chengdu area; the statistical characteristic of temperature gradient in track slab and the relationship between temperature gradient and surface air temperature were tested and analyzed. The results show that the track slab temperature gradient will vary periodically according to the surface air temperature, and show a clear nonlinearity along the height direction. The temperature gradient distribution is extremely uneven： the temperature gradient in the top part of the track slab is larger than that in the bottom part; the most frequently occurring temperature gradient of the track slab is around -3.5 ℃/m and more than 75 % locates in the level -10 to 10 ℃/m; concrete with a relatively good heat exchange condition with the surrounding air has a narrower band distribution. In addition, the frequency distribution histogram should exclude the time zone from 00：00 to 06：00 because there is almost no traffic in this period. The amplitude of track slab temperature variation is obviously lower than that of the air temperature variation, and the former is approximately linear with the latter.展开更多
Background and aims:Human positive cofactor 4(PC4)is associated with the development and therapeutic resistance of several malignancies.However,the role of PC4 in hepatocellular carcinoma(HCC)remains obscure.Methods:T...Background and aims:Human positive cofactor 4(PC4)is associated with the development and therapeutic resistance of several malignancies.However,the role of PC4 in hepatocellular carcinoma(HCC)remains obscure.Methods:The expression status of PC4 was explored in Gene Expression Omnibus and The Cancer Genome Atlas datasets.Subsequently,the prognostic and diagnostic significance of PC4 in HCC patients was analyzed.Functional enrichment analyses were conducted to explore biological functions and potential mechanisms.The CIBERSORT algorithm was used for immune infiltration analysis.The risk signature was constructed by LASSO-Cox regression and was validated with the International Cancer Genome Consortium dataset.Quantitative real-time polymerase chain reaction was used to verify the expression levels of all genes.Tumor Immune Dysfunction and Exclusion analysis evaluated immunotherapy response.Finally,using online databases,PC4-related competing endogenous RNA networks were constructed.Results:PC4 levels were significantly upregulated in HCC and positively correlated with the pathological grade and clinical stage.The PC4-high expression group showed worse prognosis.In addition,PC4 could distinguish between tumor and normal tissues with an area under the curve of 0.965.The PC4 level was associated with immune checkpoints and immune cell infiltration.In the training and validation sets,the eight-gene risk signature strongly correlated with HCC patient prognosis.Tumor Immune Dysfunction and Exclusion analysis showed that patients in both the PC4-low and low-risk groups were more likely to benefit from immunotherapy.Finally,an lncRNA/microRNA-101-3p/PC4 network was constructed.Conclusion:We confirmed PC4 as a diagnostic and prognostic biomarker in HCC patients.We also developed and validated an eight-gene risk signature,which will help in clinical decision-making.The competing endogenous RNA network could help explore the regulatory mechanisms of PC4 in HCC.展开更多
Directed energy deposition has been used to repair superalloy components in aero engines and gas turbines.However,the microstructure and properties are generally inhomogeneous in components because of the different pr...Directed energy deposition has been used to repair superalloy components in aero engines and gas turbines.However,the microstructure and properties are generally inhomogeneous in components because of the different processing histories.Here,the microstructures and wear behavior of different zones(substrate,HAZ,and deposit)are investigated for the IC10 directionally solidified superalloy repaired by the directed energy deposition process.It is found that the microstructure of the deposited layers is strongly textured with a<001>-fiber texture in the building direction,and the texture intensity is continuously increased along the building direction.Two kinds ofγ’phase(primary and secondaryγ’phase)can be found in the heat-affected zone(HAZ),and the average size of primaryγ’phase is smaller than that in the substrate due to liquation.In the deposit layers,the size ofγ’phase is much smaller than those in the substrate and the primaryγ’phase of HAZ;both size and the fraction of theγ’phase decreases with the increase of building height.The wear rate of the substrate is the smallest,indicating the best wear resistance;while the wear rate of HAZ is the largest,indicating the worst wear resistance in the repaired sample.The wear rates in the deposit layers increase from the bottom to the top zones,showing a decreasing wear resistance.Abrasive wear is found to be the dominant wear mechanism of the repaired alloy,and the resistance to which is closely related to the fraction ofγ’phase in the microstructure.The understanding of the influence of microstructure on wear resistance allows for a more informed application of inhomogeneous superalloy components repaired by directed energy deposition in industry.展开更多
基金the financial support for this work from the National Natural Science Foundation of China(No.52205334)the Natural Science Foundation of Hunan Province,China(No.2022JJ40495)+2 种基金the Changsha Key Research and Development Project,China(No.kh2201275)the Changsha Municipal Natural Science Foundation,China(No.kq2202196)the Tribology Science Fund of State Key Laboratory of Tribology in Advanced Equipment,China(No.SKLTKF21B08)。
基金supported by the National Key Basic Research Program of China (973 Program) (2013CB036202)the National Natural Science Foundation of China (51008258)Fundamental Research Funds for the Central Universities (SWJTU12CX065)
文摘Temperature is one of the important loads for designing slab track. The characteristic of slab track tem- perature varies greatly with different regional climates. In this work, a bi-block slab track model was built under outdoor conditions in Chengdu area; the statistical characteristic of temperature gradient in track slab and the relationship between temperature gradient and surface air temperature were tested and analyzed. The results show that the track slab temperature gradient will vary periodically according to the surface air temperature, and show a clear nonlinearity along the height direction. The temperature gradient distribution is extremely uneven： the temperature gradient in the top part of the track slab is larger than that in the bottom part; the most frequently occurring temperature gradient of the track slab is around -3.5 ℃/m and more than 75 % locates in the level -10 to 10 ℃/m; concrete with a relatively good heat exchange condition with the surrounding air has a narrower band distribution. In addition, the frequency distribution histogram should exclude the time zone from 00：00 to 06：00 because there is almost no traffic in this period. The amplitude of track slab temperature variation is obviously lower than that of the air temperature variation, and the former is approximately linear with the latter.
文摘Background and aims:Human positive cofactor 4(PC4)is associated with the development and therapeutic resistance of several malignancies.However,the role of PC4 in hepatocellular carcinoma(HCC)remains obscure.Methods:The expression status of PC4 was explored in Gene Expression Omnibus and The Cancer Genome Atlas datasets.Subsequently,the prognostic and diagnostic significance of PC4 in HCC patients was analyzed.Functional enrichment analyses were conducted to explore biological functions and potential mechanisms.The CIBERSORT algorithm was used for immune infiltration analysis.The risk signature was constructed by LASSO-Cox regression and was validated with the International Cancer Genome Consortium dataset.Quantitative real-time polymerase chain reaction was used to verify the expression levels of all genes.Tumor Immune Dysfunction and Exclusion analysis evaluated immunotherapy response.Finally,using online databases,PC4-related competing endogenous RNA networks were constructed.Results:PC4 levels were significantly upregulated in HCC and positively correlated with the pathological grade and clinical stage.The PC4-high expression group showed worse prognosis.In addition,PC4 could distinguish between tumor and normal tissues with an area under the curve of 0.965.The PC4 level was associated with immune checkpoints and immune cell infiltration.In the training and validation sets,the eight-gene risk signature strongly correlated with HCC patient prognosis.Tumor Immune Dysfunction and Exclusion analysis showed that patients in both the PC4-low and low-risk groups were more likely to benefit from immunotherapy.Finally,an lncRNA/microRNA-101-3p/PC4 network was constructed.Conclusion:We confirmed PC4 as a diagnostic and prognostic biomarker in HCC patients.We also developed and validated an eight-gene risk signature,which will help in clinical decision-making.The competing endogenous RNA network could help explore the regulatory mechanisms of PC4 in HCC.
基金financial support to this work from the Tribology Science Fund of the State Key Laboratory of Tribology(SKLT2020C09)National Natural Science Foundation of China(No.51675303)National Key Research and Development Program of China(2017YFB1103300)。
文摘Directed energy deposition has been used to repair superalloy components in aero engines and gas turbines.However,the microstructure and properties are generally inhomogeneous in components because of the different processing histories.Here,the microstructures and wear behavior of different zones(substrate,HAZ,and deposit)are investigated for the IC10 directionally solidified superalloy repaired by the directed energy deposition process.It is found that the microstructure of the deposited layers is strongly textured with a<001>-fiber texture in the building direction,and the texture intensity is continuously increased along the building direction.Two kinds ofγ’phase(primary and secondaryγ’phase)can be found in the heat-affected zone(HAZ),and the average size of primaryγ’phase is smaller than that in the substrate due to liquation.In the deposit layers,the size ofγ’phase is much smaller than those in the substrate and the primaryγ’phase of HAZ;both size and the fraction of theγ’phase decreases with the increase of building height.The wear rate of the substrate is the smallest,indicating the best wear resistance;while the wear rate of HAZ is the largest,indicating the worst wear resistance in the repaired sample.The wear rates in the deposit layers increase from the bottom to the top zones,showing a decreasing wear resistance.Abrasive wear is found to be the dominant wear mechanism of the repaired alloy,and the resistance to which is closely related to the fraction ofγ’phase in the microstructure.The understanding of the influence of microstructure on wear resistance allows for a more informed application of inhomogeneous superalloy components repaired by directed energy deposition in industry.
