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【Objective】It is complex, time-consuming and laborious for conventional chemical detection method to detect the content of total nitrogen, potassium, total sugars, reducing sugars, total alkali, chlorine and magnesium in wrapper tobacco, while near-infrared spectroscopy technology is simple to operate and rapid to detect. The aims is to establish a near infrared spectroscopy detection model to achieve rapid quantitative analysis of the content of the seven chemical components in wrapper tobacco.【Method】Taking Yunnan cigar wrapper tobacco as the material, conventional chemical method was used to detect the content of seven chemical components in wrapper tobacco, and then near infrared spectroscopy was used to analyze the content of seven chemical components and their spectruml data of wrapper tobacco by using near infrared spectroscopy combined with partial least squares method, and the model with the optimal predictive performance was determined by comparing the root mean square error and correlation coefficient of the model.【Result】The optimal prediction results of the seven chemical components were established by the preprocessing methods of original spectrum, first derivative, first derivative, original spectrum, original spectrum, first derivative + median filtering and first derivative + median filtering, and the optimal principal component numbers were 20, 7, 4, 24, 21, 9 and 7, respectively; The training set correlation coefficients (r) of the seven models were 0.9441, 0.8589, 0.7664, 0.9511, 0.9547, 0.9031 and 0.8620, respectively. The root mean square error of cross validation (RMSECV) were 0.1288, 0.2846, 0.0280, 0.0096, 0.1894, 0.2965 and 0.0795; The correlation coefficients (r) of the validation set were 0.8958, 0.7675, 0.7181, 0.7928, 0.7282, 0.8062 and 0.7980, and the root mean square error of prediction (RMSEP) were 0.1789, 0.3011, 0.0324, 0.0193, 0.3855, 0.3990 and 0.0999. Moreover, the models were externally verified, and the results indicated that the average RSD of the predicted values and chemical values of the seven chemical components were less than 32%.【Conclusion】It was feasible to use near infrared spectroscopy to rapidly and quantitatively analyze the contents of seven chemical components in wrapper tobacco. The models had good prediction effect on the contents of seven chemical components, and could provide a reference for the rapidly and quantitatively analysis of seven chemical components in wrapper tobacco.

Abstract: Objective To investigate the relationship between serum microRNA-874-3p (miR-874-3p), microRNA-181a-5p (miR-181a-5p), Wnt/β-catenin signaling pathway and neurological function prognosis in patients with acute ischemic stroke (AIS). Methods AIS patients who received intravenous thrombolytic therapy in Shenzhen Longhua District Central Hospital from March 2021 to December 2022 were prospectively included into the AIS group, and healthy subjects during the same period were selected into the control group. The relative expression levels of serum miR-874-3p, miR-181a-5p and peripheral blood mononuclear cell (PBMC) determination of Wnt/β-catenin were detected and compared between the two groups. Pearson correlation was used to analyze the correlation between the expression of miR-874-3p and miR-181a-5p in serum and the Wnt/β-catenin signaling pathway in AIS patients. All AIS patients were followed up for 3 months after discharge. Patients who completed follow-up were divided into the good neurological function prognosis group and the poor neurological function prognosis group based on the mRS score. The relative expression levels of miR-874-3p and miR-181a-5p were compared between the two groups. Multivariate logistic regression equation was used to analyze the factors affecting the prognosis of neurological function in AIS patients. Results In this study, 185 patients were included in the AIS group, with an average age of (62.8±7.3) years. The control group included 65 healthy subjects with an average age of (63.4±6.9) years. Compared with the control group, the relative expression levels of miR-874-3p in serum (1.02±0.21 vs. 1.46±0.23, P