It is very difficult to reasonably evaluate the loads acting on coal pillars in longwall panels during the planning of a new pillar system. The application of empirical equations is a common practice in calculating co...It is very difficult to reasonably evaluate the loads acting on coal pillars in longwall panels during the planning of a new pillar system. The application of empirical equations is a common practice in calculating coal pillar loads while designing a new pillar. This paper proposes numerical models for evaluating coal pillar loads. The key of building a successful numerical model for calculating coal pillar loads lies in the fact that the model should represent the redistribution of stress all over the longwall panels and the surrounding areas, and it is especially important to include the characteristics of the stress rebuilding process in the gob areas, which are crucial for the building process of coal pillar loads. Based on the geo-mechanical background of the Baoshan Coal Mine, this paper details the procedures of applying numerical models to the evaluation of coal pillar loads and their local practices. The study results show it is feasible and reasonable to use numerical models to evaluate coal pillar loads.展开更多
Objective: To study the regulating effect of luteolin on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition. Methods: Colon cancer HT-29 cells were cultured and randomly divided int...Objective: To study the regulating effect of luteolin on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition. Methods: Colon cancer HT-29 cells were cultured and randomly divided into two groups, control group were treated with serum-free medium without drugs and LUT group were treated with serum-free medium containing luteolin. After 24 h of treatment, cells were collected to extract RNA, and then fluorescent quantitative PCR method was used to determine the mRNA expression of proliferation genes, migration genes and epithelial-mesenchymal transition genes. Results: After 24 h of luteolin treatment, Lrig1, TSPYL5, Bim, SOX15 and DLC1 mRNA expression in LUT group were significantly higher than those in control group while RPS15a, Bad, TRPV5, TRPV6, PLD2, IBP, SphK1, FAK, Vimentin and N-cadherin mRNA expression were significantly lower than those in control group. Conclusion: Luteolin has inhibiting effect on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition.展开更多
Objective: To study the effect of luteolin on HepG2 liver cancer cell proliferation in vitro and angiogenesis activity. Methods: HepG2 liver cancer cell lines were cultured and divided into the luteolin group that wer...Objective: To study the effect of luteolin on HepG2 liver cancer cell proliferation in vitro and angiogenesis activity. Methods: HepG2 liver cancer cell lines were cultured and divided into the luteolin group that were treated with serum-free medium containing 100 μmol/L luteolin and the normal control group that treated with serum-free medium containing drugs. After 24 h of treatment, MTT kit was used to detect the cell proliferation activity, and fluorescence quantitative PCR kit was used to detect the mRNA expression of pro-proliferation genes, pro-apoptosis genes and angiogenesis molecules. Results: After 24 h of treatment, the cell proliferation activity of luteolin group was significantly lower than that of normal control group;LETM1, URG11, PICK1, CyclinD1, Uba2, VEGF, Fra-1, HIF-1 and Rac1 mRNA expression in luteolin group were significantly lower than those in normal control group while Merlin, AlkBH8, ARID1A and Panx1 mRNA expression were significantly higher than those in normal control group. Conclusion: Luteolin has inhibiting effect on the HepG2 liver cancer cell proliferation in vitro and angiogenesis activity.展开更多
Optimizing the ventilation design of packaging system is of crucial importance for improving the efficiency of the forced-air precooling process to maintain the quality of horticultural produce and extend the shelf li...Optimizing the ventilation design of packaging system is of crucial importance for improving the efficiency of the forced-air precooling process to maintain the quality of horticultural produce and extend the shelf life in food cold chain.Many efforts had been devoted to the study about the impact of ventilation design on airflow and temperature distribution inside ventilated packages.This paper reviews relevant research methods,commonly used quantities for the measurement of precooling effectiveness,attractive design parameters,and their impact on precooling effectiveness.These allow us to know exactly the characteristic and deficiency of each research method,identify dominant design parameters,and seek a promising way for the future improvement of the ventilated packaging system.展开更多
In this article,natural convection of a magnetic fluid in a cubic cavity with a heat generating object inside and under a uniform magnetic field is simulated by the lattice Boltzmann method.Results obtained from the p...In this article,natural convection of a magnetic fluid in a cubic cavity with a heat generating object inside and under a uniform magnetic field is simulated by the lattice Boltzmann method.Results obtained from the present simulations are shown to be agreed well with our experimental measurements,and reveal more of effects of the magnetic field on the flow and heat transfer of the magnetic fluids.展开更多
文摘背景超声在颈动脉斑块筛查、密度结构判定、稳定性评估等方面发挥着重要作用.剪切波超声弹性成像(shear wave elastography,SWE)作为一种全新的超声弹性成像方法,可通过分析剪切波传播速度来定量评估生物组织的弹性硬度信息.因此,运用SWE定量分析不同类型颈动脉斑块的硬度特征,可为临床评估斑块稳定性提供有价值的参考.目的运用SWE测定脂肪肝患者不同类型颈动脉斑块硬度,探讨其与血脂水平相关性.方法回顾性分析130例存在颈动脉单一斑块的脂肪肝患者临床资料,共计130个斑块.根据常规超声下斑块回声不同分为3组:软斑块组(40例)、混合性斑块组(52例)、硬斑块组(38例).对所有斑块行SWE检查,测量各斑块平均杨氏模量值,并分析其与低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)以及高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)水平的相关性.结果硬斑块组平均杨氏模量值、HDL-C水平明显高于混合性斑块组及软斑块组,差异有统计学意义(P<0.05);混合性斑块组平均杨氏模量值、HDL-C水平明显高于软斑块组,差异有统计学意义(P<0.05);硬斑块组LDL-C水平明显低于混合性斑块组及软斑块组,差异有统计学意义(P<0.05);混合性斑块组LDL-C水平明显低于软斑块组,差异有统计学意义(P<0.05);颈动脉斑块平均杨氏模量值与LDL-C水平呈负相关性(r=-0.71,P<0.05),与HDL-C水平呈正相关性(r=0.75,P<0.05).结论SWE能定量评估不同类型颈动脉斑块的软硬度,其平均杨氏模量值与血脂水平具有一定相关性,可为临床评估斑块稳定性提供硬度信息.
文摘It is very difficult to reasonably evaluate the loads acting on coal pillars in longwall panels during the planning of a new pillar system. The application of empirical equations is a common practice in calculating coal pillar loads while designing a new pillar. This paper proposes numerical models for evaluating coal pillar loads. The key of building a successful numerical model for calculating coal pillar loads lies in the fact that the model should represent the redistribution of stress all over the longwall panels and the surrounding areas, and it is especially important to include the characteristics of the stress rebuilding process in the gob areas, which are crucial for the building process of coal pillar loads. Based on the geo-mechanical background of the Baoshan Coal Mine, this paper details the procedures of applying numerical models to the evaluation of coal pillar loads and their local practices. The study results show it is feasible and reasonable to use numerical models to evaluate coal pillar loads.
基金National Natural Science Foundation of China No:21273283.
文摘Objective: To study the regulating effect of luteolin on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition. Methods: Colon cancer HT-29 cells were cultured and randomly divided into two groups, control group were treated with serum-free medium without drugs and LUT group were treated with serum-free medium containing luteolin. After 24 h of treatment, cells were collected to extract RNA, and then fluorescent quantitative PCR method was used to determine the mRNA expression of proliferation genes, migration genes and epithelial-mesenchymal transition genes. Results: After 24 h of luteolin treatment, Lrig1, TSPYL5, Bim, SOX15 and DLC1 mRNA expression in LUT group were significantly higher than those in control group while RPS15a, Bad, TRPV5, TRPV6, PLD2, IBP, SphK1, FAK, Vimentin and N-cadherin mRNA expression were significantly lower than those in control group. Conclusion: Luteolin has inhibiting effect on colon cancer HT-29 cell proliferation, migration and epithelial-mesenchymal transition.
基金National Natural Science Foundation of China No:21273283.
文摘Objective: To study the effect of luteolin on HepG2 liver cancer cell proliferation in vitro and angiogenesis activity. Methods: HepG2 liver cancer cell lines were cultured and divided into the luteolin group that were treated with serum-free medium containing 100 μmol/L luteolin and the normal control group that treated with serum-free medium containing drugs. After 24 h of treatment, MTT kit was used to detect the cell proliferation activity, and fluorescence quantitative PCR kit was used to detect the mRNA expression of pro-proliferation genes, pro-apoptosis genes and angiogenesis molecules. Results: After 24 h of treatment, the cell proliferation activity of luteolin group was significantly lower than that of normal control group;LETM1, URG11, PICK1, CyclinD1, Uba2, VEGF, Fra-1, HIF-1 and Rac1 mRNA expression in luteolin group were significantly lower than those in normal control group while Merlin, AlkBH8, ARID1A and Panx1 mRNA expression were significantly higher than those in normal control group. Conclusion: Luteolin has inhibiting effect on the HepG2 liver cancer cell proliferation in vitro and angiogenesis activity.
基金This work is supported by the National Key R&D Program of China(Grant No.2016YFD0400100).
文摘Optimizing the ventilation design of packaging system is of crucial importance for improving the efficiency of the forced-air precooling process to maintain the quality of horticultural produce and extend the shelf life in food cold chain.Many efforts had been devoted to the study about the impact of ventilation design on airflow and temperature distribution inside ventilated packages.This paper reviews relevant research methods,commonly used quantities for the measurement of precooling effectiveness,attractive design parameters,and their impact on precooling effectiveness.These allow us to know exactly the characteristic and deficiency of each research method,identify dominant design parameters,and seek a promising way for the future improvement of the ventilated packaging system.
基金supported by a grant-in-aid for Scientific Research(C)from the Ministry of Education,Culture,Sports,Science and Technology of Japan.
文摘In this article,natural convection of a magnetic fluid in a cubic cavity with a heat generating object inside and under a uniform magnetic field is simulated by the lattice Boltzmann method.Results obtained from the present simulations are shown to be agreed well with our experimental measurements,and reveal more of effects of the magnetic field on the flow and heat transfer of the magnetic fluids.
