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[Objective] Key construction technologies for large-diameter shield tunneling in sand and gravel strata are summarized and analyzed, including shield machine model selection, shield launching and receiving, and shield excavation posture control. Specific construction control parameters and measures are proposed to reduce cutterhead tool wear, decrease stratum losses, and minimize land subsidence and deformation. [Method] Considering the engineering structural characteristics, such as the loose structure, non-cemented or weakly cemented particles, large particle size, and strong permeability of sand and gravel strata, theoretical analysis and on-site monitoring methods are employed to deeply analyze the key construction technologies for large-diameter shield tunneling in sand and gravel strata, from aspects of shield machine model selection, shield originating and receiving, shield excavation posture control, as well as shield cutterhead tool detection-maintenance. [Result & Conclusion] The cutterhead opening rate, cutterhead tool models, and spoil improvement scheme of large-diameter shield should be specially designed according to the stratigraphical structure characteristics, facilitating efficient shield spoil discharge and advance cutting. Comprehensive reinforcement measures, such as stratum grouting consolidation, large pipe shed support, and construction dewatering, should be adopted at shield tunnel shaft end to ensure strata stability during large-diameter shield launching or receiving. In large-diameter shield tunneling, the control of parameters such as cutterhead rotational speed, spoil discharge rate, and spoil discharge temperature should be emphasized, along with appropriate increases in grouting volume to improve spoil modification effects and avoid excessive over-excavation, keeping stratum losses within a reasonable range. By implementing the aforementioned construction parameters and measures, the risk of shield excavation can be controlled, while significantly enhancing construction quality and efficiency, and substantially reducing construction costs.

Aiming at the problems that the fly ash in coal-fired power plant flue gas can easily lead to the blockage of dust collectors and air preheaters, a 410 t/h coal-fired boiler in Shanxi was taken as the research object, and a coal-fired flue gas pollution control method based on high temperature dust removal technology was proposed. The material treatment route was used to study the influence of the SCR pre-high temperature filter on the pressure drop of the flue gas treatment system process, and to determine the optimal operating parameters of each equipment. The Aspen Plus simulation software was used to build relevant models through the combination of relevant modules to simulate the flue gas treatment processes such as high temperature dust collector, SCR, ozonation, ammonia desulfurization and so on, and the technical and economic analysis was carried out. At the same time, the engineering test data were used to verify the model. The influence of equipment operation parameters on pollutant emission characteristics was studied through its sensitivity analysis function. The results show that the use of high temperature dust collector in the system can effectively alleviate the blockage problem of SCR device, significantly reduce the flow pressure drop and reduce the power consumption of induced draft fan. The SCR denitrification unit has the best denitrification efficiency at 320−350 ℃ and the ammonia nitrogen ratio of 1.0−1.1. The O3/NO value should be controlled around 1.05 when using ozone pre-oxidation. The high temperature of flue gas entering the desulfurization tower is not conducive to the absorption of SO2 in the flue gas, which leads to the reduction of desulfurization efficiency. Exergy loss of high temperature ash separated by high temperature dust remover is the main cause of exergy loss in the system, so energy utilization rate can be improved through the efficient utilization of high temperature ash heat. In this study, the model simulation results are consistent with the actual operation results, and the relative error between the simulation results and the actual operation value is less than 7%, showing a high accuracy. It provides a certain theoretical support and operation guidance for the optimization of multi-pollutant cooperative control and energy efficiency evaluation based on the high-temperature dust removal technology.

Non-small cell lung cancer is one of the most commom malignant tumor being harmful to people’s life and health. Most of the patients have developed to the last stage which not suitable for surgical indications, so radiation and chemotherapy is the main treatment strategy. In recent years, with the theory of anti-angiogenesis therapy for malignant tumors, apatinib as a promising novel medicine to treat malignant tumors, represents synergistic antitumor effects in combination with radiotherapy. The underlying mechanisms may include make blood vessel normalization, alleviating inner hypoxia, and angiogenic factors regulation. Apatinib in combination with radiotherapy may become a new and effective treatment strategy of non-small cell lung cancer.

With the sustained growth of economy and significant changes in social demographics, the issue of elderly-related diseases has increasingly drawn attention particularly. Alzheimer's disease (AD),as a representative disease of neurodegenerative diseases has become a major challenge, affecting the health and quality of life among the elderly population severely. In recent years, the incidence, prevalence, and mortality rate of AD increase in China, imposing substantial economic burdens on families, society, and the entire healthcare system. To proactively address this challenge and respond to the national 'Healthy China Action' initiative, leading experts from Renji Hospital, Shanghai Jiao Tong University School of Medicine,and Chinese Center for Disease Control and Prevention Chronic Non-communicable Disease Control Center, Fudan University School of Public Health, Shanghai Mental Health Center, Ruijin Hospital,Shanghai Jiao Tong University School of Medicine, Fujian Medical University, and other authoritative institutions, have jointly authored the 'China Alzheimer Disease Report 2024'. Building upon previous editions of 2021, 2022, and 2023, this report updates epidemiological data on AD in China, thoroughly analyzes the latest economic burdens of the disease, and comprehensively evaluates the current status of AD diagnosis and treatment services, as well as the allocation of public health resources in our country. The release of the 'China Alzheimer Disease Report 2024' not only reflects China's progress and efforts in AD research and prevention, but also underscores the social heightened concern for elderly health issues. It aims to provide scientific and technical guidance and robust data support for the prevention, diagnosis, and treatment of AD, offering a professional basis for the government and relevant departments to formulate targeted health policies and intervention measures. Furthermore, it serves as a platform for promoting academic exchanges and cooperation in this field domestically and internationally. Through the dissemination and application of this report, we anticipate it will not only serve as a reference for professionals but also enhance public awareness of AD, promote active participation across various sectors of society, and jointly advance the development of elderly health care in China, empowering us towards achieving 'healthy aging'.

Background and objective Drugs which block tumor angiogenesis will be likely effective towards inhibiting tumor growth for angiogenesis being a prerequisite for tumor growth and metastasis. Therefore, antiangiogenesis has become a promising strategy for the treatment of cancer. Investigation on both antiangiogenic effect and mechanism(s) of oyster polypeptide (OPP) were performed via experiments of chicken embryos model in vivo and human umbilical vein endothelial cells (HUVECs) in vitro. Methods The methods employed in experiment were chorioallantoic membrane (CAM) angiogenesis in chicken embryos in vivo, MTT cell survival assay, flat plate scarification, transwell plates assay, matrigel-induced tube formation assay and transmission electron microscope et al. and the OPP’s effects on angiogenesis was observed. Results Study showed that treatment with OPP resulted in significant inhibition of chorioallantoic membrane (CAM) angiogenesis in chicken embryos. MTT cell survival assay showed that treatment with OPP resulted in strong inhibition of HUVECs growth, with an IC50 of 400 μg/mL. Flat plate scarification suggested that OPP (200 μg/mL, 400 μg/mL and 800 μg/mL) distinctly inhibited HUVECs’ migration (18.75%, 37.93%, 74.07% respectively, treatment for 12 h). Treatment with OPP of different concentrations (200 μg/mL, 400 μg/mL and 800 μg/mL) significantly reduced the density of the migration cells by 15.5%, 37.2% and 67.24% (P