Objective:To investigate the application of time series models in forecasting pre-hospital emergency ambulance trips in Handan City and develop the LPro ensemble model for improved prediction accuracy to support emergency resource allocation.Methods:Pre-hospital emergency data from Handan Emergency Medical Command Center (2019-2023) were retrospectively analyzed. From 324 799 original records, 289 949 valid records were included after cleaning. The training set (2019-2022: 215 918 records) included 35 527 records in 2019, 52 015 in 2020, 61 836 in 2021, and 66 540 in 2022. The validation set (2023) contained 74 031 records. ARIMA, linear trend seasonal, exponential smoothing, and Prophet models were fitted to the training set. The LPro ensemble model was constructed using MAPE-based weighting (linear trend seasonal model: 0.38, Prophet: 0.62). Performance metrics included MAPE, RMSE, MAE, and R 2. Results:Data showed annual growth (compound annual growth rate 23.27%) and seasonal patterns (October peaks, February troughs). Ambulance dispatches increased annually with monthly cyclical patterns. For 2023 validation predictions: ARIMA (MAPE 8.76%, RMSE 619, MAE 491, R 2 0.4563), linear trend seasonal (MAPE 9.83%, RMSE 671, MAE 545, R 2 0.3608), Prophet (MAPE 8.43%, RMSE 562, MAE 503, R 2 0.5513), exponential smoothing (MAPE 8.08%, RMSE 643, MAE 410, R 2 0.4124). LPro model showed superior performance (MAPE 7.05%, RMSE 491, MAE 393, R 2 0.6570), with 16.37% lower MAPE, 12.63% lower RMSE, 21.87% lower MAE, and 19.17% higher R 2 versus Prophet. Conclusion:The LPro ensemble model substantially enhances prediction accuracy and reliability, offering scientific support for emergency resource optimization and dispatch scheduling in Handan City.

Objective:To determine the equilibrium solubility and the apparent oil/water partition coefficient of nebivolol hydrochloride to provide experimental basis for the development of new preparations.Methods:The concentration of nebivolol hydrochloride was determined by an HPLC method,and a saturated solution method and a shake-flask method were respectively applied to determine the equilibrium solubility and the apparent oil/water partition coefficient of nebivolol hydrochloride in water,0.1 mol·L-1 HCl solution and phosphate buffer solution with different pH values(pH2.0,pH6.8,pH7.4 and pH8.0).Results:At (37±0.5)℃,the equilibrium solubility of nebivolol hydrochloride in water and in 0.1 mol·L-1 HCl solution was 722.53 μg·ml-1and 56.07μg·ml-1,respectively.The apparent oil/water partition coefficient (Log P) of nebivolol hydrochloride was 1.17 and 1.32,respectively.Within the pH range of 2.0-7.4,with the increase of pH value, the equilibrium solubility and the Log P decreased and increased,respectively,while pH value increased from 7.4 to 8.0,the equilibrium solubility of nebivolol hydrochloride increased and Log P decreased.Conclusion:The method is accurate and reliable.Nebivolol hydrochloride has poor water solubility,and the equilibrium solubility and the Log P are both influenced by pH values.