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[ Objective ] The NAC transcription factor family is a class of transcription factors that is widely studied in plants. It plays an important role in regulating plant growth and development and responding to abiotic stress. Maize is one of the three major food crops , which faces various adverse stresses in growth and development. Salt stress is one of the main environmental factors limiting crop growth and produc- tion. Therefore , it is of great significance to identify maize salt resistance genes and analyze their salt re- sistance mechanism for breeding stress-resistant maize varieties. [ Methods ] This study cloned the maize transcription factor ZmNAC59 and analyzed its conserved domain and phylogenetic relationship using bioinformatics methods. The expression pattern of the gene in leaves under NaCl and MeJA treatments was analyzed using the quantitative real-time PCR method. The stable transgenic system was used to het- erologously express the gene in Arabidopsis thaliana for phenotype observation. At the same time , virus- induced silencing technology was used to silence the gene in maize , followed by phenotype observation un- der salt stress and enzyme activity detection. [ Results ] The qRT-PCR results showed that ZmNAC59 was up-regulated by NaCl and MeJA treatments. After virus-induced silencing of ZmNAC59 , the silenced strains were more sensitive to salt stress and accumulated more ROS. After over expression of ZmNAC59 in A . thaliana , the over expression lines had higher survival rate , less accumulation of ROS , and lower Na + / K + ratios under salt stress , indicating that ZmNAC59 , as a positive regulator of salt stress , can im- prove plant salt resistance by regulating ion homeostasis. qRT-PCR results showed that Na + and K + transport related genes were significantly up-regulated in A . thaliana overexpression lines. After transient expression of ZmNAC59 in maize protoplasts , the expression of ZmSOS1 , ZmNHX1 , and ZmNHX7 were significantly up-regulated after salt treatment. The Dual-LUC experiment showed that ZmSOS1 was the target gene of ZmNAC59. [ Conclusion ] This study finds that ZmNAC59 activates ZmSOS1 promoter and regulates its expression to promote ion transport under salt stress , thereby improving plant salt resist- ance. This provides a basis for the screening of maize stress resistant genes and variety cultivation.

Background The status of patients with HIV/AIDS co-infected with HCV considerably varies in different parts of China. The co-infection of HIV and HCV accelerates the clinical progress of the disease, thereby reducing the patients' quality of life and exacerbating the occurrence of death. Currently, there are relatively few studies on patients with HIV/AIDS co-infected with HCV in Guizhou. Objective To analyze the status of patients with HIV/AIDS co-infected with HCV in Guizhou and its influencing factors and consequently provide basis for its early detection, diagnosis, and treatment. Methods The cases included in this study were a cohort of HIV/AIDS patients who received antiviral therapy (ART) in the public health rescue center of Guangzhou from March 2006 to December 2020. Finally, 3 084 patients who met the study requirements were included. Patients' sex, age, ethnicity, education level, occupation, marital status, route of infection, year of diagnosis, and CD4+ T-lymphocytes before ART and anti HCV levels were collected. Multivariate Logistic regression model were used to identify influencing factors of patients with HIV/AIDS co-infected with HCV. Results Among the 3 084 patients with HIV/AIDS, 202 were co-infected with HCV, and the co-infection rate was 6.55%. There were significant differences in HCV infection rates among patients with HIV/AIDS of different age groups, education levels, occupations, route of infection (P0.05) . The prevalence of HCV infection among HIV/AIDS patients tended to decrease with increasing year of diagnosis and increasing levels of CD4+ T lymphocytes (P

A linearized model of frequency measurement for the Free Induction Decay (FID) signal is proposed to increase the Proton Magnetometer (PM) precision. First, the nonlinear model of frequency measurement is set up according to the characteristic of the FID signal. Then, according to the error analysis of the MCFM method, the model is linearized on the condition of precision requirement. Furthermore, to reduce the nonlinear error caused by approximate treatment and the trigger time error caused by the random noise, the Least Squares (LS) method is adopted to estimate the slope of the linearized model, and the frequency to be measured is the inverse of the slope. Finally, a PM Prototype is made to verify the effectiveness of the proposed method. Experimental results show that the precision of frequency measurement is obviously increased if the proposed method is adopted for the noised sine signal. Moreover, the RMSD and the NPSD of magnetic-field measurement are about 0.13 nT and 80 pT/Hz1/2, respectively if the proposed method is adopted by PM, which is better than the comparison method.

At present, the globalization of the world economy continues to intensify, and the pace of technological modernization is accelerating. Artificial intelligence methods such as big data and financial sharing are gradually replacing traditional working methods in all walks of life, and the accounting industry is no exception. Under the dual impact of globalization and the development of artificial intelligence, the demand for training international compound accounting professionals is large and increasing, "CPA examination system" as one of the most authoritative examinations in the field of accounting, its matching with the current environment is particularly important. Starting from the current status of CPA examination, the author has made an in-depth investigation and study on the CPA examination systems in many countries including China, the United States, Britain, Japan, Germany and Australia by consulting a large number of relevant literature. Meanwhile, they systematically analyzed the CPA examination systems in various countries from four dimensions: examination organization, examination threshold, examination cycle and examination subjects, explored the similarities and differences of CPA examination systems in the world's mainstream countries, and summarized the common problems and the advantages that can be used for reference, which has practical significance for the design and update of the CPA examination system in China. At the same time, it provides reference significance for improving the professional quality of accounting personnel and accelerating the pace of changing the functions of accounting personnel.