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Against the backdrop of rapid global economic development, the Beijing-Tianjin-Hebei (BTH) region, a pivotal economic hub and environmentally sensitive area in China, faces significant challenges in sustaining its landscape ecosystem. Given the region's strategic importance and vulnerability to environmental pressures, this study investigated the intricate relationships between landscape ecological risk, urban expansion, and economic growth (EG) in the BTH region. Utilizing the landscape as the focal point, we constructed a decoupling model at the grid scale to explore the decoupling relationship between the landscape ecological risk index (ERI), construction area growth (CAG), and EG. The results showed that (1) distinct stages and regional disparities were observed in the trends of ERI, CAG, and EG within the BTH region. The hot and cold spot patterns for these factors did not align consistently. (2) From 1995 to 2019, the coupling relationship between ERI, CAG, and EG in the BTH region underwent a fluctuating transition, initially moving from an undesirable state to an ideal state, and subsequently reverting to an undesirable state. Although the overall trends in these relationships showed some convergence, there were notable spatial distribution differences. (3) The spatial heterogeneity of the two decoupling relationships in the BTH region was relatively poor. Further analysis revealed that the evolution of these decoupling relationships was closely intertwined with regional policy shifts and adjustments. [ABSTRACT FROM AUTHOR]

With the development of urban agglomerations in China, the study of the interactions between cities has become a popular and difficult issue. Exploring the interactions between cities can help decision-makers optimize regional resource allocation and improve regional spatial patterns. Combining the urban flow model and the patch-generating land use simulation (PLUS) model, this study simulates and analyzes the process of urban expansion in the Beijing–Tianjin–Hebei (BTH) region, and investigates the impact of urban hierarchical structure differences on urban expansion. In this study, the role and influence of inter-city economy flow, transportation flow, population flow, and information flow on the development of urban agglomerations are comprehensively considered, and a multilevel urban interaction model is constructed based on a hierarchical generalized linear model (HGLM). Based on the national BTH cooperation and development strategy, a multi-scenario simulation study of urban expansion is carried out using the HGLM-PLUS model. The results indicate the following: (1) compared to the traditional PLUS model, the coupled HGLM-PLUS model, which considers multilevel urban flows, improved the overall accuracy by 0.047, the Kappa coefficient by 0.207, and the figure of merit (FoM) index by 0.051; (2) under different simulation scenarios, the development trend under the cooperation and development policy in the BTH region is more stable, demonstrating a relatively smooth urbanization expansion trend; and (3) under the BTH cooperation and development background, the total area of construction land in the BTH region is expected to be maintained at around 1,164,500 km2 by 2040. The spatial expansion pattern will present a networked expansion with the core driving development, axes and belts connecting, and clusters breaking through. [ABSTRACT FROM AUTHOR]

In order to obtain the cold roll-beating spline surface roughness processing parameter domain suitable for different working conditions. Based on the principle of cold roll-beating spline forming,carry out cold roll-beating spline surface roughness test,using the test results to construct a surface prediction model for surface roughness response of cold roll-beating spline,using the analysis of variance,test sample test and comparison of experimental and predicted values,it is verified that the predictive model is feasible. Analyze the variation of the rotational speed of the rolling wheel,the feed rate of the workpiece and the surface roughness,the processing parameter domain of the surface roughness of the cold roll-beating spline is determined based on the surface roughness accuracy level comparison table. The results show: The rotational speed of the rolling wheel is 976 r/min ～ 2936 r/min,and the workpiece feed rate is in the range of 7 mm/min ～ 56 mm/min,with the gradual increase of the rotational speed of the rolling wheel and the feed rate of the workpiece,the surface roughness shows a trend of decreasing first and then increasing. Five sets of processing parameters were randomly extracted from the processing parameter fields corresponding to each accuracy level,and the maximum relative error between the surface roughness test value and the predicted value was 2. 75 %.Therefore,it is shown that the determined cold roll-beating spline surface roughness processing parameter domain is accurate and reliable. The research results have important application value and certain theoretical guiding significance for controlling the surface roughness of cold roll-beating spline.

Many developed cities in the world put forward a spatial development strategy in their construction planning. Analyzing the development level of the urban spatial structure and the influence of driving factors has become a hot topic. Based on 709,232 points of interest data in Beijing, China, this paper integrates nighttime light data and population density data to select eight key driving factors from three perspectives: urban function configuration, economic activity intensity and population spatial distribution. Geodetector is used to optimize data discreteness and highlight the spatial heterogeneity of the development level. We use the technique for order of preference by similarity to ideal solution (TOPSIS) model improved with the entropy weight method to grade the spatial differentiation characteristics of the comprehensive development level. The driving factors and their effects on space are further discussed using Geodetector. The results are as follows: (1) The quartile method can achieve the optimal dispersion of all urban functions. The standard deviation can achieve the optimal dispersion of economic activity intensity and population spatial distribution; (2) A comparison with the "Beijing Urban Master Plan (2016–2035)", finds that the optimized evaluation system can effectively reflect the spatial heterogeneity of urban spatial structure development. It verifies the rationality of the evaluation methods and factors; (3) The driving force of the population under single-factor driving is 0.8428. The dual-factor driving force with population participation ranges from 0.8992 to 0.9550. The results of the study are significant and reflect the prominent role of population on the development level of spatial structure in Beijing. This paper aims to provide a new idea for the study of the interior space planning of large inland cities. [ABSTRACT FROM AUTHOR]

The development of novel therapeutic strategies and modalities for tumors is still one of the important areas of current scientific research. Low permeability and short residence time of drugs in solid tumor areas are important reasons for the low efficiency of existing therapeutic strategies. Typically, nanoparticles with large size displayed enhanced residence time but low permeability. Therefore, to prolong the retention time of materials in solid tumors, size‐increasing strategies have been developed to directly generate large‐scale nanoparticles using small molecular compounds or increase the size of small nanoparticles in solid tumor areas. In this review, we summarize recently reported activatable aggregation systems that could be activated by cancer‐related substances for cancer therapy and classify them by the mechanisms that lead to aggregation. In the end, we propose some potential challenges briefly from the view of our opinion. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease [ABSTRACT FROM AUTHOR]

Due to the structural characteristics of railway turnouts, as well as their vulnerability to damage and other problems, the environmental vibrations induced by urban rail transit often have a greater effect on the railway turnouts than that on an ordinary line. Therefore, it is necessary to carry out an in-depth study on the characteristics of vibration source on the turnouts. In this paper, a group of representative turnouts is selected for field testing on four typical lines of different operational times in a Chinese city. The profile and rail irregularity of the turnouts are measured to evaluate the service condition of the turnouts and the wheel–rail interaction. The vibration acceleration of the track structure and tunnel wall is measured as the train passes the turnout by setting the measuring points in the two main vibration sources, including the switch and the crossing section. The time–frequency domain analysis method is used to analyze these data. It is found that the source strength of the tunnel wall in the crossing section is much greater than that in the switch section, and that the lateral vibration level is often greater than the vertical vibration level. Unexpectedly, there is a low positive correlation between the vibration level and the train speed, while the healthy state of the turnout rails has a great influence on the vibration level. According to the results of the research, the sources of vibration excitation in the turnouts are complex; therefore, it is necessary to comprehensively evaluate their environmental impact and take corresponding vibration control measures. [ABSTRACT FROM AUTHOR]

The development of novel therapeutic strategies and modalities for tumors is still one of the important areas of current scientific research. Low permeability and short residence time of drugs in solid tumor areas are important reasons for the low efficiency of existing therapeutic strategies. Typically, nanoparticles with large size displayed enhanced residence time but low permeability. Therefore, to prolong the retention time of materials in solid tumors, size-increasing strategies have been developed to directly generate large-scale nanoparticles using small molecular compounds or increase the size of small nanoparticles in solid tumor areas. In this review, we summarize recently reported activatable aggregation systems that could be activated by cancer-related substances for cancer therapy and classify them by the mechanisms that lead to aggregation. In the end, we propose some potential challenges briefly from the view of our opinion. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease., (© 2022 Wiley Periodicals LLC.)