This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried o...This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried out from the two nearest days (previous and following of quietest day). The study uses International Reference Ionosphere (IRI) for ionosphere modeling. The located station is Ouagadougou, in West Africa. Solar minimum of phase 22 is considered in this study. Using three core principles of ionosphere modeling under IRI running conditions, the study enables to carry out Peak of electron density in F2-layer values during the quietest days of the characteristic months for the four different seasons. These parameters are compared to those of the previous and the following of the quietest days (the day before and following each quietest selected day) at the same hour. The knowledge of NmF2 values at the quietest days and at the two nearest days enables to calculate the relative error that can be made on this parameter. This calculation highlights insignificant relative errors. This means that NmF2 values at the two nearest days of each quietest day on solar minimum can be used for simulating the quietest days’ behavior. NmF2 values obtained by running IRI model have good correlation with those carried out by Thermosphere-Ionosphere-Electrodynamics-General Circulation Model (TIEGCM).展开更多
Ionosphere layer is the atmosphere region which reflects radio waves for telecommunication. The density in particles in this layer influences the quality of communication. This study deals with the effects of Total El...Ionosphere layer is the atmosphere region which reflects radio waves for telecommunication. The density in particles in this layer influences the quality of communication. This study deals with the effects of Total Electron Contents (TEC) on the critical frequency of radio waves in the F2-layer. Total Electron Contents parameter symbolizes electron bulk surface density in ionosphere layer. Above critical frequency value in F2 layer (foF2), radio waves pass through ionosphere. The knowledge of this value enables to calibrate transmission frequencies. In this study, we consider TEC effects on foF2 under quiet time conditions during the maximum and the minimum of solar cycle 22, at Ouagadougou station, in West Africa. The study also considers the effects of seasons and the hourly variability of TEC and foF2. This work shows winter anomaly on foF2 and TEC on minimum and maximum of solar cycle phase respectively. Running International Reference Ionosphere (IRI) model enables to carry out the effects of TEC on foF2 by use of their monthly average values. This leads to a new approach to calibrate radio transmitters.展开更多
BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS...BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS Sixty-two CRC patients admitted to the hospital were enrolled into the study group,and sixty healthy people from the same period were assigned to the control group.Elbow venous blood was sampled from the patients and healthy individuals,and blood serum was saved for later analysis.MiR-19a-3p mimics,miR-19a-3p inhibitor,miR-negative control,small interfering-FOXF2,and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells.Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells,and western blot(WB)analysis was conducted to evaluate the levels of FOXF2,glycogen synthase kinase 3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),β-catenin,p-β-catenin,α-catenin,Ncadherin,E-cadherin,and vimentin.The MTT,Transwell,and wound healing assays were applied to analyze cell proliferation,invasion,and migration,respectively,and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2.RESULTS The patients showed high serum levels of miR-19a-3p and low levels of FOXF2,and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8.MiR-19a-3p and FOXF2 were related to sex,tumor size,age,tumor-nodemetastasis staging,lymph node metastasis,and differentiation of CRC patients.Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelialmesenchymal transition,invasion,migration,and proliferation of cells.WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β,β-catenin,N-cadherin,and vimentin;and increased the levels of GSK-3β,p-β-catenin,α-catenin,and Ecadherin.The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2.In addition,a rescue experiment revealed that there were no differences in cell proliferation,invasion,and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group.CONCLUSION Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway,thereby affecting the epithelial-mesenchymal transition,proliferation,invasion,and migration of cells.Thus,miR-19a-3p is likely to be a therapeutic target in CRC.展开更多
文摘This study deals with Peak of electron density in F2-layer sensibility scale during quiet time on solar minimum. Peaks of electron density in F2-layer (NmF2) values at the quietest days are compared to those carried out from the two nearest days (previous and following of quietest day). The study uses International Reference Ionosphere (IRI) for ionosphere modeling. The located station is Ouagadougou, in West Africa. Solar minimum of phase 22 is considered in this study. Using three core principles of ionosphere modeling under IRI running conditions, the study enables to carry out Peak of electron density in F2-layer values during the quietest days of the characteristic months for the four different seasons. These parameters are compared to those of the previous and the following of the quietest days (the day before and following each quietest selected day) at the same hour. The knowledge of NmF2 values at the quietest days and at the two nearest days enables to calculate the relative error that can be made on this parameter. This calculation highlights insignificant relative errors. This means that NmF2 values at the two nearest days of each quietest day on solar minimum can be used for simulating the quietest days’ behavior. NmF2 values obtained by running IRI model have good correlation with those carried out by Thermosphere-Ionosphere-Electrodynamics-General Circulation Model (TIEGCM).
文摘Ionosphere layer is the atmosphere region which reflects radio waves for telecommunication. The density in particles in this layer influences the quality of communication. This study deals with the effects of Total Electron Contents (TEC) on the critical frequency of radio waves in the F2-layer. Total Electron Contents parameter symbolizes electron bulk surface density in ionosphere layer. Above critical frequency value in F2 layer (foF2), radio waves pass through ionosphere. The knowledge of this value enables to calibrate transmission frequencies. In this study, we consider TEC effects on foF2 under quiet time conditions during the maximum and the minimum of solar cycle 22, at Ouagadougou station, in West Africa. The study also considers the effects of seasons and the hourly variability of TEC and foF2. This work shows winter anomaly on foF2 and TEC on minimum and maximum of solar cycle phase respectively. Running International Reference Ionosphere (IRI) model enables to carry out the effects of TEC on foF2 by use of their monthly average values. This leads to a new approach to calibrate radio transmitters.
文摘BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS Sixty-two CRC patients admitted to the hospital were enrolled into the study group,and sixty healthy people from the same period were assigned to the control group.Elbow venous blood was sampled from the patients and healthy individuals,and blood serum was saved for later analysis.MiR-19a-3p mimics,miR-19a-3p inhibitor,miR-negative control,small interfering-FOXF2,and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells.Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells,and western blot(WB)analysis was conducted to evaluate the levels of FOXF2,glycogen synthase kinase 3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),β-catenin,p-β-catenin,α-catenin,Ncadherin,E-cadherin,and vimentin.The MTT,Transwell,and wound healing assays were applied to analyze cell proliferation,invasion,and migration,respectively,and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2.RESULTS The patients showed high serum levels of miR-19a-3p and low levels of FOXF2,and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8.MiR-19a-3p and FOXF2 were related to sex,tumor size,age,tumor-nodemetastasis staging,lymph node metastasis,and differentiation of CRC patients.Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelialmesenchymal transition,invasion,migration,and proliferation of cells.WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β,β-catenin,N-cadherin,and vimentin;and increased the levels of GSK-3β,p-β-catenin,α-catenin,and Ecadherin.The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2.In addition,a rescue experiment revealed that there were no differences in cell proliferation,invasion,and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group.CONCLUSION Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway,thereby affecting the epithelial-mesenchymal transition,proliferation,invasion,and migration of cells.Thus,miR-19a-3p is likely to be a therapeutic target in CRC.