Calibrating and testing the discrete element parameters for peanut seedling film

This study constructed a numerical model using the discrete element software EDEM to address the current lack of calibrated contact parameters for peanut seedling membranes and the absence of precise simulation model parameters for mechanized separation. The Hysteretic Spring Contact Model (HSCM) was employed to calibrate the contact parameters of peanut seedling membranes. The angle of repose of peanut seedling membranes was determined through image processing combined with the least squares method. Through central composite design (CCD), a second-order response model linking the contact parameters to the angle of repose was established. Optimization was achieved by using the angle of repose obtained from physical tests as the objective. Secondary simulation tests were conducted with the calibrated parameters, revealing a relative error of 1.37% between the simulated and physical angles of repose. This confirmed the effectiveness of the parameters in calibrating peanut seedling membrane characteristics. The findings offer theoretical and empirical support for discrete element simulations of peanut seedling membrane separation and peanut straw pulverization processes.

Direct Reduction of Solid Fe_2O_3 in Molten CaCl_2 by Potentially Green Process

Sintered （300℃） porous pellets of Fe2O3 were electrolyzed to Fe in molten CaCl2 （800-900℃） under argon at 1.8-3.2 V for 2-20 h. The laboratory scale experiments show that it was a potentially direct green method to produce Fe powder. At lower electrolysis voltage （〈2.2 V）, higher current efficiency （〉90%） and smaller energy consumption （-3.0 kWh/kg） can be obtained. When the electrolysis voltage was above 2.4 V, the deposition of metal Ca from the salt lowered the current efficiency and increased the energy consumption. The electrolysis voltage also had effects on the micrographs of the reduced powder. The cubic particles can be seen in the products at the voltage lower than 2.2 V; when the voltage was higher than 2.2 V, it was nodular. The reduction proceeds at the cathode in two steps, i.e., from Fe2O3 to FeO and then to Fe. The oxygen emits at the anode. The process is potentially free of carbon emission and produces two useful products at both cathode and anode, promising a zero-emission technology for the extractive metallurgical industry.

Circular BANP knockdown inhibits the malignant progression of residual hepatocellular carcinoma after insufficient radiofrequency ablation

Background:Circular RNAs(circRNAs)are endogenous non-coding RNAs,some of which have pathological roles.The current study aimed to explore the role of circRNA BTG3-associated nuclear protein(circ-BANP)binding with let-7f-5p and its regulation of the toll-like receptor 4(TLR4)/signal transducer and activator of transcription 3(STAT3)signaling pathway in residual hepatocellular carcinoma(HCC)after insufficient radiofrequency ablation(RFA).Methods:Circ-BANP,let-7f-5p,and TLR4 expressions in HCC samples were assessed using reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and Western blotting.Bioinformatics prediction,RNA pull-down assay,and dual luciferase reporter gene assay were used to analyze the relationships among circ-BANP,let-7f-5p,and TLR4.Huh7 cells were used to generate an in vitro model of residual HCC,defined as Huh7-H cells,which were transfected with either a plasmid or the sequence of circ-BANP,let-7f-5p,or TLR4.Expression of circ-BANP,let-7f-5p,and TLR4 mRNA was determined by RT-qPCR.TLR4,STAT3,p-STAT3,vascular endothelial growth factor A,vascular endothelial growth factor receptor-2,and epithelialmesenchymal transformation(EMT)-related factors proteins were determined by Western blotting.Cell proliferation was determined by cell counting kit-8 and 5-Ethynyl-2’-deoxyuridine(EdU)assay and cell migration and invasion by Transwell assay.Animal studies were performed by inducing xenograft tumors in nude mice.Results:Circ-BANP and TLR4 mRNAs were upregulated in HCC tissues(the fold change for circ-BANP was 1.958 and that for TLR4 was 1.736 relative to para-tumors)and expression further increased following insufficient RFA(fold change for circBANP was 2.407 and that of TLR4 was 2.224 relative to para-tumors).Expression of let-7f-5p showed an opposite tendency(fold change for let-7f-5p in HCC tissues was 0.491 and that in tumors after insufficient RFA was 0.300 relative to paratumors).Competitive binding of circ-BANP to let-7f-5p was demonstrated and TLR4 was identified as a target of let-7f-5p(P<0.01).Knockdown of circ-BANP or elevation of let-7f-5p expression inhibited the TLR4/STAT3 signaling pathway,proliferation,invasion,migration,angiogenesis,and EMT in Huh7 and Huh7-H cells(P<0.01).The effects induced by circBANP knockdown were reversed by let-7f-5p inhibition.Overexpression of TLR4 reversed the impact of let-7f-5p upregulation on the cells(P<0.01).Silencing of circ-BANP inhibited the in vivo growth of residual HCC cells after insufficient RFA(P<0.01).Conclusions:Knockdown of circ-BANP upregulated let-7f-5p to inhibit proliferation,migration,and EMT formation in residual HCC remaining after insufficient RFA.Effects occur via regulation of the TLR4/STAT3 signaling pathway.

An Outbreak of Multidrug-Resistant Tuberculosis in a Secondary School --Hubei Province, 2019

What is already known about this topic?Multidrug-resistant tuberculosis(MDR-TB)is a type of tuberculosis with resistance to common treatments such as isoniazid and rifampicin.MDR-TB is a major global health challenge and needs to be controlled tightly through prevention measures,early diagnosis,and full treatment and management.What is added by this report?This outbreak was the first MDR-TB related public health emergency in Hubei Province.In total,five MDR-TB cases and nine clinically diagnosed cases were identified within one class in a secondary school.Students and teachers from other classes were monitored,but no other cases were found.What are the implications for public health practice?The implementation of TB prevention and control measures in schools is important to increase knowledge on TB and to raise awareness on protecting personal wellbeing.The Automatic Early Warning Information System alerted the local health department and allowed for a timely response to prevent further disease spread.