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Porphyrin and its derivatives have become the second generation of photosensitizers for photodynamic therapy for cancers. 5,10,15,20-Tetrakis­[4-(2-hydroxy­ethoxy)­phenyl]­porphyrin photosensitizer was modified into a porphyrin-based ATRP initiator, and it was further used to construct star-shaped glycopolymers bearing galactose residuals by using atom transfer radical polymerization. Four star-shaped glycopolymers were obtained with a porphyrin core bearing four glyco-arms of varying arm lengths. They can be dissolved in water and displayed good light absorption and fluorescent emission due to the presence of porphyrin core. They generated singlet oxygen which may photobleach the indicator 1,3-diphenyl­isobenzofuran. The galactose-containing polymers show Hep G2 cells (a human liver cancer cell line) affinity which was selected for the toxicity study. These polymers caused lower cell viability in phototoxicity (1 h light irradiation), indicating their effectiveness as photosensitizers. The fluorescence microscopy results are in good agreement with 1O2 generation and the toxicity study, which indicates their effectiveness for potential use in photodynamic therapy. The star polymers with shorter glyco-arms have higher porphyrin content per unit mass, leading more efficient 1O2 generation to cancer cell extermination, while the polymers with longer glyco-arms showed lower toxicity and better lectin recognition and affinity. It is important to balance the photodynamic therapy and cell targeting property for practical applications.

Predicting the arrival aircraft's flight time plays a critical role in effectively optimizing and scheduling spatial-temporal resources in the terminal airspace. This paper focuses on a data-driven method for predicting the arrival flight time. First, based on the existing research, a feature set is constructed from four aspects: initial state, arrival pressure, sequencing pressure, and wind information, which are believed to affect arrival flight time significantly. Second, eight widely used models are developed to predict flight time, including linear regression models, nonlinear regression models, and tree-based ensemble models. Furthermore, the stacking technique is adopted to improve the prediction performance. Finally, take Guangzhou Baiyun International Airport as a study case to verify the proposed method's effectiveness. The results indicate that the arrival pressure (describing the arrival traffic demand) and the sequencing pressure (sketching the arrival traffic distribution) could effectively improve the prediction accuracy. The mean absolute percentage error of the predicted flight time via ATAGA and IGONO can be increased by 1%. Besides, the proposed method of extracting wind data could also improve the prediction performance. The mean absolute error of the predicted flight time via GYA can be reduced by 4.85 s.

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Air traffic administration requires evidence when promoting new technology or a new concept of operation. Therefore, when decision support tools are applied, it is necessary to analyze the costs and benefits quantitatively. This paper focuses on the evaluation of Key Performance Indicators (KPIs) correlated with the improvement of arrival operations after the implementation of the Arrival Management (AMAN) system and Wake Turbulence Re-categorization in China (RECAT-CN). Firstly, we give an overview of the implementation of the AMAN system and RECAT in China. Secondly, the KPIs related to the arrival operation are established according to the characteristics of AMAN and RECAT-CN, based on the existing KPI systems in the field of Air Traffic Management (ATM). The proposed KPIs are: airport acceptance rate; final approach interval; flight time within the terminal area (TMA); and taxi-in time. Thirdly, arrival operation within the TMA around Guangzhou International Airport is used as an example to carry out the quantitative analysis. The region and time range were defined for the performance comparison, and external factors were also examined. Finally, using descriptive and inferential statistics, the proposed KPIs’ comparison results are presented and visualized. Such results indicate a significant improvement in arrival operation with the AMAN system and RECAT-CN at Guangzhou International Airport.