Mobile phone sensor-based detection of subjective cannabis intoxication in young adults: A feasibility study in real-world settings.

BACKGROUND: Given possible impairment in psychomotor functioning related to acute cannabis intoxication, we explored whether smartphone-based sensors (e.g., accelerometer) can detect self-reported episodes of acute cannabis intoxication (subjective "high" state) in the natural environment. METHODS: Young adults (ages 18-25) in Pittsburgh, PA, who reported cannabis use at least twice per week, completed up to 30 days of daily data collection: phone surveys (3 times/day), self-initiated reports of cannabis use (start/stop time, subjective cannabis intoxication rating: 0-10, 10 = very high), and continuous phone sensor data. We tested multiple models with Light Gradient Boosting Machine (LGBM) in distinguishing "not intoxicated" (rating = 0) vs subjective cannabis "low-intoxication" (rating = 1-3) vs "moderate-intensive intoxication" (rating = 4-10). We tested the importance of time features (i.e., day of the week, time of day) relative to smartphone sensor data only on model performance, since time features alone might predict "routines" in cannabis intoxication. RESULTS: Young adults (N = 57; 58 % female) reported 451 cannabis use episodes, mean subjective intoxication rating = 3.77 (SD = 2.64). LGBM, the best performing classifier, had 60 % accuracy using time features to detect subjective "high" (Area Under the Curve [AUC] = 0.82). Combining smartphone sensor data with time features improved model performance: 90 % accuracy (AUC = 0.98). Important smartphone features to detect subjective cannabis intoxication included travel (GPS) and movement (accelerometer). CONCLUSIONS: This proof-of-concept study indicates the feasibility of using phone sensors to detect subjective cannabis intoxication in the natural environment, with potential implications for triggering just-in-time interventions.

[The Study of Three-Dimensional Synchronous Fluorescence Spectral Characteristics of Liuwei Dihuang Pills].

Three-dimensional synchronous fluorescence of each component of Liuwei dihuang pills (Prepared rehmannia root, cornel, yam, alisma, poria cocos, and cortex moutan) is measured by using FLS920P fluorescence spectrometer. Feature parameters were extracted. It can be found that each component is fluorescent material and the lines are all different. Furthermore, Three-dimensional synchronous fluorescence of Liuwei dihuang pills boiling with standard water and non-standard water are all measured and there are significant differences between them. It can be applied in distinguishing different formula of Chinese medicine decoction. Experimental and Theoretical conclusion show that: the three-dimensional fluorescence spectrometry method and the combination of synchronous fluorescence spectroscopy method can further improve the sensitivity and selectivity of fluorescence spectroscopy, have a distinct advantage in a complex multi-component mixture of fluorescence spectroscopic analysis. The study can provide a convenient and reliable method for establishing a complete fingerprint of Chinese traditional medicine. It also can help identifying the component and the quality of Chinese patent medicine.

[Identification of Prepared Rehmannia Root in Different Regions by Using Derivative Synchronous Fluorescence Spectrum].

Three-dimensional synchronous fluorescence spectrum of prepared rehmannia root from different regions were measured and feature parameters were extracted. It can be found that the effective fluorescent compositions of prepared rehmannia root from different regions are similar. The relationships between the spectrum-effect were established. This study can provide reference for clinicaldosage. First order derivative and second order derivative of prepared rehmanniaroot from different regions can be got by programming respectively. Magnifing synchronous emission spectrum of the shoulder strap, the subtle differences of the spectrum can be distinguished and the method, derivative synchronous fluorescence spectrum, to identify different regions of prepared rehmannia root are acquired.