Background Health and education are two closely related factors that affect human development. A limited number of studies have been conducted in China, most of which have been based on small sample sizes and with inconsistent results. The study investigates the association between mortality rate and educational level in China based on the sixth national population census in 2010.Methods This is large-scale population study based on the nationally administrated data sets of population census in 2010, 2000 and 1990. The 2010 census covered a total population of 1 332 810,869 in China. ResultsIn general, standardized mortality rate decreased as educational level increased. The standardized mortality rate is higher among males than among females with equivalent educational levels. The standardized mortality rate in all the educational groups declined to varying degrees from 1990. 2000 to 2010. The standardised mortality rate declined with increasing educational levels from no education to university undergraduate groups in 1990, 2000 and 2010. The standardized mortality rate declined as the degree of education increased in cities, towns, and villages, but gradually increased at the same educational level from cities, towns, to villages in general. The difference in each region is considerable and the population quality of the developed area is generally high. The percentage of the uneducated population to the total population aged 15 years and over (%) was positively correlated with the standardized mortality rate. By contrast, the percentage of the population with a high school education to the total population aged 6 years and over (%) was negatively correlated with the standardized mortality rate.

This study was aimed to investigate the application of micro ribonucleic acid (miRNA) combined with nanographene particles in molecular diagnosis of depression. After the sheet-shaped graphene oxide was mixed with a solvent to form a solution, it was atomized at high temperature to form droplets and extract nanographene oxide, which was applied to an electrochemical sensor. 90 patients with depression were selected as the research objects and they were randomly divided into control group and experimental group, patients from the two groups received the miRNA molecular diagnosis and the miRNA molecular diagnosis combined with nanographene electrochemical sensor dopamine detection method, respectively. As a result, the diagnostic sensitivity (82.4%), specificity (90.3%), and accurate index (71.3%) of patients from the experimental group were higher obviously than those of the control group (54.3%, 72.8%, and 55.6%) (P <0.05). The expression levels of MiR-92b-5p and MiR-19a-3p in patients with depression were higher markedly than the levels of the normal population (P <0.05). The detection rates of mild depression, moderate depression, and severe depression in patients from the experimental group were 97.3%, 96.5%, and 91.2%, which were higher greatly than the rates of the control group (84.3%, 85.4%, and 83.2%) (P <0.05). Besides, the false positive rate (11.2%) and false negative rate (5.6%) of patients from the experimental group were sharply lower than the rates of the control group (31.5% and 16.4%) (P <0.05). In short, miRNA combined with nanographene electrochemical sensors could accurately diagnose depression with high accuracy and sensitivity, which could be applied in the clinical diagnosis.