Area Triangulation Method for Automatic Detection of Venous Emptying Maneuvers

Abstract Venous refilling time (VRT) can diagnose the presence of venous diseases in lower limbs. In order to calculate VRT it is necessary to determine the End of the Emptying Maneuvers (EEM). First Derivative Method (FDM) can be employed for automatic detection of the EEM, but its sensitivity to artifacts and noise can degrade its performance. In contrast, studies report that Area Triangulation Method (ATM) evinces effectiveness in biosignals point finding. This work compares the exactness of ATM and FDM for recognition of the EEM. The annotations made by 3 trained human observers on 37 photoplethysmography records were used as a reference. Bland-Altman graphics supported the analysis of agreement among human observers and methods, which was complemented with Analysis of variance and Multiple Comparisons statistical tests. Results showed that ATM is more accurate than FDM for automatic detection of the EEM, with statistically significant differences (p-value < 0.01).

Rapid Judgement of Blending Endpoint of Jingqi Shuangshen Capsules and Content Determination of Astragaloside Ⅳ by AOTF-NIR / 中国药房

OBJECTIVE:To establish the method for rapid judgement of blending endpoint of Jingqi shuangshen capsules and content determination of astragaloside Ⅳ. METHODS:AOTF-NIR combined with principal component analysis and Moving Block Standard Deviation method was used to identify the blending endpoint. First derivative combined with savitzky-golay filter method were used to spectrum pretreatment. The partial least square method was used to establish quantitative analysis model of the content of astragaloside Ⅳin mixed endpoint sample. The content of astragaloside Ⅳ in mixed endpoint sample was determined by HPLC-ELSD to validate the model. RESULTS:Methodology validation of content determination of astragaloside Ⅳ in mixed material sample and mixed endpoint sample was in line with the requirements. NIR monitoring results showed that the product reached the blending endpoint after 30 min. The results of NIR monitoring were generally consistent with the results of HPLC-ELSD. The principal component dimension of the quantitative model was 9;determination coefficients was 0.954 9;Root Mean Square of Calibration of the model was 0.039 2;Root Mean Square Error of Prediction of the model was 0.042 6. Predicted average value of astragaloside Ⅳ by NIR was 11.74 mg/g,and measured average value of astragaloside Ⅳ by HPLC-ELSD was 11.38 mg/g;average deviation was 3.16%. CONCLUSIONS:AOTF-NIR can rapidly judge the blending endpoint sample of Jingqi shuangshen capsules,rapidly determine the content of astragalosideⅣin mixed endpoint material,improve the quality control level of blending process and shorten blending cycle.