Establishment of farmers' professional cooperatives is an effective approach of settling conflicts between small-scale production of rural households and great market, however, there are still many problems such a...Establishment of farmers' professional cooperatives is an effective approach of settling conflicts between small-scale production of rural households and great market, however, there are still many problems such as low level of standardization, unscientific market positioning, poor capacity of mitigating risks, and unfavorable ecological benefits. This study, based on field investigation data and successful support experience, further explored operation and management problems existing in Jilin Farming Cooperative, and proposed pertinent solutions so as to enhance the high-efficiency and standard operation of farmers' professional cooperatives in Jilin Province and even China.展开更多
In the feeding process of aluminum electrolytic, feeding quantity of alumina affects eventually dissolved quantity at the end of a feeding cycle. Based on the OpenFOAM platform, dissolution model coupled with heat and...In the feeding process of aluminum electrolytic, feeding quantity of alumina affects eventually dissolved quantity at the end of a feeding cycle. Based on the OpenFOAM platform, dissolution model coupled with heat and mass transfer was established. Applying the Rosin-Rammler function, alumina particle size distribution under different feeding quantities was obtained. The temperature response of electrolyte after feeding was included and calculated, and the dissolution processes of alumina with different feeding quantities (0.6, 0.8, 1.0, 1.2, 1.4, 1.6 kg) after feeding were simulated in 300 kA aluminum reduction cell. The results show that with the increase of feeding quantity, accumulated mass fraction of dissolved alumina decreases, and the time required for the rapid dissolution stage extends. When the feeding quantity is 0.6 kg and 1.2 kg, it takes the shortest time for the electrolyte temperature dropping before rebounding back. With the increase of feeding quantity, the dissolution rate in the rapid dissolution stage increases at first and then decreases gradually. The most suitable feeding quantity is 1.2 kg. The fitting equation of alumina dissolution curve under different feeding quantities is obtained, which can be used to evaluate the alumina dissolution and guide the feeding quantity and feeding cycle.展开更多
Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation grow...Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation growth factor-β1(TGF-β1)in lipopolysaccharide(LPS)-induced glomerular mesangial cells(GMCs).Methods The rat GMCs line(HBZY-1)were cultured and randomly divided into 5 groups,including control,LPS(100 ng/mL),and 5,10,20µmol/L RSV-treated groups.In addition,SphK1 inhibitor(SK-II)was used as positive control.GMCs were pretreated with RSV for 2 h and treated with LPS for another 24 h.GMCs proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The proteins expression of SphK1,p-c-Jun and TGF-β1 in GMCs were detected by Western blot,and DNA-binding activity of AP-1 was performed by electrophoretic mobility shift assay(EMSA).The binding activity between RSV and SphK1 protein was detected by AutoDock Vina and visualized by Discovery Studio 2016.Results LPS could obviously stimulate GMCs proliferation,elevate SphK1,p-c-Jun and TGF-β1 expression levels and increase the DNA-binding activity of AP-1(P<0.05 or P<0.01),whereas these effects were significantly blocked by RSV pretreatment.It was also suggested that the effect of RSV was similar to SK-II(P>0.05).Moreover,RSV exhibited good binding affinity towards SphK1,with docking scores of−8.1 kcal/moL and formed hydrogen bonds with ASP-178 and LEU-268 in SphK1.Conclusion RSV inhibited LPS-induced GMCs proliferation and TGF-β1 expression,which may be independent of its hypoglycemic effect on preventing the development of mesangial cell fibrosis and closely related to the direct inhibition of SphK1 pathway.展开更多
基金Supported by Research on Scientific Renovation and Sustainable Economic Development (Program of Humanities and Social Science Foundation of the Ministry of Education,09YJA790080)Systematic Analysis of Agricultural Scientific and Technological Progress in Jilin Province (the "Eleventh Five-year" Research Program of Social Science of Jilin Department of Education)Operation Design of Farmers'Professional Cooperatives in Gongzhuling City (Undergraduates' Inno-vative Experiment Program of Jilin University,2010C83280)
文摘Establishment of farmers' professional cooperatives is an effective approach of settling conflicts between small-scale production of rural households and great market, however, there are still many problems such as low level of standardization, unscientific market positioning, poor capacity of mitigating risks, and unfavorable ecological benefits. This study, based on field investigation data and successful support experience, further explored operation and management problems existing in Jilin Farming Cooperative, and proposed pertinent solutions so as to enhance the high-efficiency and standard operation of farmers' professional cooperatives in Jilin Province and even China.
基金Project(2010AA065201) supported by the High-Tech Research and Development Program of ChinaProject(2018zzts157) supported by the Fundamental Research Funds for the Central Universities,China
文摘In the feeding process of aluminum electrolytic, feeding quantity of alumina affects eventually dissolved quantity at the end of a feeding cycle. Based on the OpenFOAM platform, dissolution model coupled with heat and mass transfer was established. Applying the Rosin-Rammler function, alumina particle size distribution under different feeding quantities was obtained. The temperature response of electrolyte after feeding was included and calculated, and the dissolution processes of alumina with different feeding quantities (0.6, 0.8, 1.0, 1.2, 1.4, 1.6 kg) after feeding were simulated in 300 kA aluminum reduction cell. The results show that with the increase of feeding quantity, accumulated mass fraction of dissolved alumina decreases, and the time required for the rapid dissolution stage extends. When the feeding quantity is 0.6 kg and 1.2 kg, it takes the shortest time for the electrolyte temperature dropping before rebounding back. With the increase of feeding quantity, the dissolution rate in the rapid dissolution stage increases at first and then decreases gradually. The most suitable feeding quantity is 1.2 kg. The fitting equation of alumina dissolution curve under different feeding quantities is obtained, which can be used to evaluate the alumina dissolution and guide the feeding quantity and feeding cycle.
基金Project(2021YFB3700803) supported by the National Key Research and Development Program of ChinaProject supported by the State Key Laboratory of Powder Metallurgy (Central South University),China。
基金Supported by the National Natural Science Foundation of China(No.81603355,81900745)。
文摘Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation growth factor-β1(TGF-β1)in lipopolysaccharide(LPS)-induced glomerular mesangial cells(GMCs).Methods The rat GMCs line(HBZY-1)were cultured and randomly divided into 5 groups,including control,LPS(100 ng/mL),and 5,10,20µmol/L RSV-treated groups.In addition,SphK1 inhibitor(SK-II)was used as positive control.GMCs were pretreated with RSV for 2 h and treated with LPS for another 24 h.GMCs proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The proteins expression of SphK1,p-c-Jun and TGF-β1 in GMCs were detected by Western blot,and DNA-binding activity of AP-1 was performed by electrophoretic mobility shift assay(EMSA).The binding activity between RSV and SphK1 protein was detected by AutoDock Vina and visualized by Discovery Studio 2016.Results LPS could obviously stimulate GMCs proliferation,elevate SphK1,p-c-Jun and TGF-β1 expression levels and increase the DNA-binding activity of AP-1(P<0.05 or P<0.01),whereas these effects were significantly blocked by RSV pretreatment.It was also suggested that the effect of RSV was similar to SK-II(P>0.05).Moreover,RSV exhibited good binding affinity towards SphK1,with docking scores of−8.1 kcal/moL and formed hydrogen bonds with ASP-178 and LEU-268 in SphK1.Conclusion RSV inhibited LPS-induced GMCs proliferation and TGF-β1 expression,which may be independent of its hypoglycemic effect on preventing the development of mesangial cell fibrosis and closely related to the direct inhibition of SphK1 pathway.
