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Extreme heat events caused by climate change have seriously threatened the sustainable human-environment system development. It has become the frontier of integrated geography to scientifically assess the comprehensive impact of heat waves on the urban system and to provide stakeholders with decision support services to cope with extreme heat. This study constructed an "exposure-susceptibility-adaptive capacity" framework for urban heat vulnerability and an early warning index system based on the perspective of the human-environment system. We then proposed key early warning technologies, including an urban heat index model, multi-subject adaptive capacity coupling technology, and a multi-group vulnerability assessment criteria library. Taking urban diversified groups and urban administrators as the service target, we designed the urban heat vulnerability early warning system. The system mainly comprises a mobile application that provides users with an interactive interface, and a dedicated management backend. The mobile application has four main functions: Urban heat index forecast, Crowd heat vulnerability risk warning service, Outdoor work guidance service, and Public facility-assisted adaptation and decision support menu. The layer data and the warning message are mainly handled by the dedicated management backend. The system provides hourly location-based heat vulnerability warnings and targeted healthy living tips for tourists, the elderly, children, and people with heat-sensitive conditions. Additionally, the system can provide a scientific basis for communities to improve their adaptive capacity to heat waves. As a pilot, the system was deployed in Xiamen City to provide personalized support services for healthy living in hot weather to residents and communities. In September 2021, the "Urban Heat Index" module was officially launched on the "Zhi Tian Qi" public meteorological service platform of the Fujian Province. The research perspective and methodology, based on a multiscale vulnerability framework, provide an effective method to dynamically and finely characterize the impacts of extreme natural hazards. The research results support urban multi-stakeholders in managing production and life during hot weather and help authorities develop targeted disaster prevention and mitigation plans for specific areas. Moreover, the findings provide a scientific reference for planning departments to improve and optimize the spatial allocation of emergency resources.

A retrospective analysis was conducted on 58 patients with laryngeal and hypopharyngeal tumors and 27 patients with benign vocal cord lesions to explore the role of serum cytokines in these diseases’ characteristics and immunotherapy. The differences in the levels of 12 cytokines were measured. Additionally, the study examined the correlation between T helper cells (Th)1/Th2 cytokine levels and the clinical characteristics and immunotherapy efficacy of laryngeal and hypopharyngeal cancers. The results show that the balance of Th1/Th2 is biased towards Th2 in patients with laryngeal and hypopharyngeal tumors. Among these, interleukin (IL)-6 (P = 0.021) was highly expressed in laryngeal tumors, and the expression levels of IL-1β (P = 0.008), IL-6 (P = 0.005), and IL-8 (P = 0.05) were higher in patients with poorly differentiated laryngeal tumors. The level of IL-4 (P = 0.0048) was significantly correlated with tumor location. The expression levels of IL-2 (P = 0.010), IL-4 (P = 0.028), IL-10 (P = 0.011), IL-12p70 (P = 0.034), IL-17 (P = 0.024), tumor necrosis factor (TNF)-α (P = 0.003), and interferon (IFN)-γ (P = 0.007) were related to lymph node metastasis. The level of IFN-γ (P = 0.016) was correlated with the efficacy of neoadjuvant therapy, while the level of IFN-α (P = 0.013) was significantly correlated with programmed death ligand 1 (PD-L1) expression. The Principal Component Analysis (PCA) results showed that patients with tumors, poor differentiation, and lymph node metastasis had higher levels of Th1 and Th2 cytokine separation. In conclusion, the shift in the balance of Th1 and Th2 cytokine expression indicates higher tumor invasiveness, and IFN has potential as a circulating molecular marker for immunotherapy of head and neck squamous cell carcinoma.

Objective: To explore the differences in runner performance of screw groups with different differential ratios, and to clarify the effects of differential speed on the extrusion performance of polylactic acid materials. Methods: Four groups of differential twin screw groups were established by Solidworks software, meshing and finite element numerical simulation were carried out by Fluent software, the calculation results were analyzed by CFD-post software, and the contours and discounted plots of various characterization parameters were combined, and they were verified by experiments. Results: Under the condition that the inlet and outlet pressures were 0.2 MPa and 0.5 MPa, and the reference speed of a single head was 30 r/min, the screws with a differential ratio of 1∶2 and 1∶3 had their own advantages and disadvantages under different properties, and the screws with a difference ratio of 1∶2 for output and pressure in the barrel had an advantage. In terms of mixing capacity, a screw with a differential ratio of 1∶3 had an advantage. Conclusion: Compared with the traditional twin-screw extruder, the differential twin-screw extruder has a positive impact on the extrusion performance of polylactic acid materials, and can be used as a new polylactic acid production equipment.

Objective: Taking polylactic acid （PLA） as an example, the flow channel distribution of twin-screw extrusion under different pitch was studied. Methods: In Solidworks, two 3D models with variable pitch and constant pitch were drawn according to the theoretical end curve equation and modified. Workbench software was used to generate the required analysis models with the swept mesh method for the two screw configurations, and then Polyflow fluid simulation software was used to simulate the actual situation. After obtaining the post-processing results, FieldView software was used to analyze the final results. The pressure, shear rate and viscosity of polylactic acid fluid under simulated conditions were studied. Meanwhile, the residence time distribution curve RTD was analyzed by Polystat statistical module. Results: Under the same conditions, the pressure, shear rate and viscosity fluctuation of the screw with variable pitch increased, and the axial mixing performance improved, but the self-cleaning ability decreased. Conclusion: The change of pitch has a certain effect on polylactic acid, but too large change of pitch often produces adverse effects. Therefore, it is necessary to design suitable variable pitch screw according to the actual situation to improve the yield and quality.

Objective: The flow channel distribution of polylactic acid （PLA） in different groove depths of a double screw extruder was discussed. Methods: Three kinds of screw elements with different depth of screw groove and their corresponding flow channel models were established by Solidworks software. Polyflow fluid simulation software was used for numerical simulation, and FieldView software was used for numerical analysis of post-processing results. The pressure field, shear rate field, viscosity field and residence time distribution curve （RTD） of polylactic acid （PLA） in three different screw extruders with different groove depths were studied. Results: The depth of the screw groove was changed by changing the diameter of the root circle of the screw element and the corresponding diameter of the flow channel. Under the same condition, the shallower the depth of the screw groove, the greater the fluctuation of pressure and shear rate, but the smaller the fluctuation of viscosity. The deeper the screw groove, the higher the axial mixing performance. Conclusion: The change of screw groove depth has influence on the mixing performance of flow field and has certain regularity. The twin-screw extruder with comprehensive mixing performance can be selected according to the experiment for practical production.