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Tropospheric delay is one of the major error sources for space geodetic techniques, such as the global navigation satellite systems (GNSSs). The accurate priori zenith tropospheric delay (ZTD) information is of crucial importance for the accuracy of positioning and navigation and for reducing the convergence time in GNSS data processing. This article conducted the first global spatiotemporal assessment of two existing tropospheric products from Vienna University of Technology (TU Wien, TUW) and the GeoForschungsZentrum Potsdam (GFZ), namely, TUW-Vienna Mapping Function 3 (VMF3) and GFZ-VMF3. The referenced ZTD data used in this study are sourced from a screened ZTD dataset created by the Karlsruhe Institute of Technology (KIT) team in 2020, which obtained 91 088 258 screened ZTD values from 12 552 GNSS stations. The results revealed that the two products exhibited high similarity with RMSE/Bias of 16.47/−3.62 and 17.63/−2.23 mm for the TUW-VMF3 and GFZ-VMF3, respectively. Their different performances were also clearly observed from the analysis of the geographical distribution, season, and epochs. The TUW-VMF3 outperformed GFZ-VMF3 at 70.1% stations, but noted that in the European region, the GFZ-VMF3 was superior to the TUM-VMF3. In the regions of North America and Japan, both products exhibited better performance in winter, but in other regions, this seasonal trend was less pronounced. TUW-VMF3 performed better in case #1 without interpolation for two products, and GFZ-VMF3 performed better in case #2, where only TUM-VMF3 required interpolation. In case #3, where both required interpolation, TUW-VMF3 exhibited better with an RMSE of 15.59 mm, although GFZ-VMF3 outperformed in seven epochs.

This study analyzed the spatial-temporal heterogeneity of green development efficiency and its influencing factors in the growing Xuzhou Metropolitan Area for the period 2000-2015. The slacks-based measure (SBM) model, spatial autocorrelation, and the geographically weighted regression (GWR) model were used to conduct the analysis. The conclusions were as follows: first, the overall efficiency of green development of the Xuzhou Metropolitan Area decreased, the regional differences and spatial agglomeration shrunk and differences within the region were the main contributors to the regional differences of green development efficiency. Second, the counties with high-efficiency green development were distributed along the coast, and along the routes of the Beijing-Shanghai and the Eastern Longhai railways. A developing axis of the high-efficiency counties was the main feature of the spatial pattern for green development efficiency. Third, regarding spatial correlation and green development efficiency, the High-High type counties in the Xuzhou Metropolitan Area formed a centralized distribution corridor along the inter-provincial border areas of Henan and Jiangsu, whereas the Low-Low type counties were concentrated in the external, marginal parts of the metropolitan area. Fourth, the major factors (ranked in decreasing order of impact) influencing green development efficiency were innovation, government regulations, the economic development level, energy consumption, and industrial structure. These factors exerted their influence to varying extents; the influence of the same factor had different effects in different regions and obvious spatial differences were observed for the different regions.

Background: Iron homeostasis disorder and neuroinflammation are the most commonly known factors that promote the occurrence and development of cognitive impairment in people. Dexmedetomidine has an anti-inflammatory effect, and it reduces the incidence of postoperative cognitive dysfunction. Therefore, the aim of this study is to verify whether dexmedetomidine could improve lipopolysaccharide-induced iron homeostasis disorder in aged mice, and show neuroprotective effect. Methods: First part, forty 12 month old male Kunming(KM) mice were divided into group N and group D: Normal saline group (group N), Dexmedetomidine group (group D). Second part, sixty 12-month-old male KM mice were divided into the following three groups: Normal saline group (group N), Lipopolysaccharide group (group LPS) and Dexmedetomidine + Lipopolysaccharide group (group D + LPS). The mice in group D + LPS were given dexmedetomidine, and given LPS intraperitoneally 2 h later. Mice underwent an oriented navigation test and a space exploration test in the Morris Water maze (MWM) test. The expression levels of Interleukin-6 ( IL-6), L-ferritin (FTL) and Transferrin receptor-1 (TfR1) in hippocampus were detected by the Western blot analysis; the hippocampal hepcidin mRNA was detected by Real-time PCR(RT-PCR); the reactive oxygen species (ROS) in the hippocampus was measured using ROS test kit. Results: Dexmedetomidine improved the cognitive decline induced by LPS. Dexmedetomidine reduced the level of hippocampal IL-6, and it attenuated the increase in their levels caused by LPS. It had no effect on hippocampal hepcidin mRNA, FTL, TfR1 and ROS but it could attenuate the increase caused by LPS. Conclusion: Dexmedetomidine has no effect on iron metabolism pathway, but it can improve the cognitive decline and the iron disorder by reducing neuroinflammation and oxidative stress. The research indicates that dexmedetomidine plays a neuroprotective role.

This paper develops a conceptual model and an indicator system for measuring economic resilience of resource-based cities based on the theory of evolutionary resilience and the related concepts of persistence, adaptation, and transformation. Nineteen resource- based cities in Northeast China were analyzed using the indicator system. The results showed that Liaoning and Jilin provinces had higher economic resilience than Heilongjiang Province. Panjin, Benxi, and Anshan in Liaoning Province were the top three cities, while Shuangyashan and other coal-based cities in Heilongjiang Province ranked last. Metals- and petroleum-based cities had significantly higher resilience than coal-based cities. The differences in persistence, adaptability, transformation, and resilience among resource-based cities decreased since the introduction of the Northeast Revitalization Strategy in 2003. Forestry-based cities improved the most in terms of resilience, followed by metals-based and multiple-resource cities; however, resilience dropped for coal-based cities, and petroleum-based cities falling the most. The findings illustrate the importance and the way to develop a differentiated approach to improve resilience among resource-based cities.

Sustainable urbanization is not only an important research topic in the field of urbanization, but also the development direction of new-type urbanization. In this paper, we construct an index system to evaluate sustainable urbanization potential with the entropy method. Results show that potential values of sustainable urbanization in most cities are not high. Cities with higher sustainable urbanization potential values are mainly located in the central part of Northeast China. Environmental potential of sustainable urbanization is the main contributor to sustainable urbanization potential in Northeast China. There is no absolute relationship between city size and potential value, large city does not always mean greater potential. Correlation analysis shows that urbanization rate cannot reflect the sustainable urbanization potential of a region. Population urbanization is not the ultimate goal of sustainable urbanization. Unilateral pursue urbanization rate cannot improve the potential of sustainable urbanization. Towards sustainable urbanization, governments in Northeast China should revitalize local economy, pay more attention to the rural areas and develop low-carbon economy or ecological economy. Finally, this paper highlights the importance of choosing more integrated methodology or new models for measuring sustainable urbanization potential in view of the shortcomings of one method.