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【Objective】 Nonpoint source pollution poses a significant threat to the surface water environment, particularly in agricultural systems. Reconstructed wetlands are an environmentally friendly method to mitigate nonpoint source pollution. This paper investigates the efficacy of plants and their growing medium in removing pollutants from farmland receding water. 【Method】 The experiment was conducted in a subsurface-flow wetland and an ecology surface flow wetland at Bapaigan region along the bank of Duliujian River. We measured the impact of aquatic plant species, planting density, matrix materials and filling rate, and hydraulic retention time of water in the wetland on purification of the water. 【Result】 Among all treatments we compared, the combination of plant species of Scirpus tabernaemontani+ Iris tectorum and matrix of zeolite+ volcanic rock was most effective to purify the receding water, as they nurtured a microbial community which increased denitrification and dephosphorization. Keeping the hydraulic retention time 3 day and running 10 consecutive cycles can remove ammonia nitrogen, total phosphorus and chemical oxygen demand (COD) contents by 95.74%, 49.94% and 89.03%, respectively. 【Conclusion】 Following the implementation of the Bapaigan constructed wetland, the plants, substrate medium and their associated microbiome were effective to remove the pollutants from the receding water, with the effluent water quality reaching Class V standard for surface water. These findings have important implications for remediating farmland runoff using constructed wetlands in north China.

[Objective] This study is aimed at comprehensively evaluating the soil quality of different vegetation restoration types in the mountainous areas of Beijing, and further identifying the key factors affecting soil quality, so as to provide data support for vegetation restoration and reconstruction in the region. [Methods] The study utilized various vegetation types, including Platycladus orientalis pure forest, Pinus tabulaeformis pure forest, P. orientalis-P. tabulaeformis mixed forest, P. orientalis coniferous and broadleaved mixed forest, P. tabulaeformis coniferous and broadleaved mixed forest, deciduous broad-leaved mixed forest, and non-forest land (CK), with similar stand conditions, as research objects. Fourteen soil physical and chemical indicators were measured to establish the total data set (TDS) for evaluating soil quality. Principal component analysis (PCA) and Pearson correlation analysis were employed to determine the minimum data set (MDS) for soil quality evaluation. Two scoring methods, linear (L) and non-linear (NL), were used to calculate the soil quality index (SQI) and a general linear model (GLM) was employed to identify key factors influencing soil quality. [Results] The bulk density and sand content decreased, while the content of soil nutrients such as organic matter, total nitrogen, total potassium, available nitrogen, and available potassium increased after the vegetation restoration compared with the non-forest land. The screened MDS indicators for soil quality evaluation in the study area were total nitrogen (TN), sand content, total potassium (TK), pH, and available water capacity (AWC). Under the four methods (SQI-LT, SQI-NLT, SQI-LM, and SQI-NLM), the SQI values of different vegetation restoration types were ranked as deciduous broadleaf mixed forest > P. orientalis coniferous and broadleaved mixed forest > P. tabulaeformis pure forest > P. tabulaeformis coniferous and broadleaved mixed forest > P. orientalis-P. tabulaeformis mixed forest > P. orientalis pure forest > non-forest land, and the soil quality significantly improved after vegetation restoration. The soil quality evaluation method of SQI-NLM exhibited better applicability in the mountainous areas of Beijing. Compared with non-forested land, the SQI-NLM of other vegetation restoration types improved by 64%, 48%, 45%, 36%, 33% and 27%, respectively. The GLM model accounted for 85.24% of the total variation in the soil quality index, with vegetation type explaining the largest proportion of the soil quality index (45.09%). [Conclusion] The selection of suitable vegetation restoration types is crucial for improving regional soil quality. In future vegetation restoration efforts, priority should be given to broad-leaved species in tree species selection. Additionally, the choice of silvicultural configuration should depend on the tree species, such as introducing native broad-leaved species into Platycladus orientalis pure forest to form a Platycladus orientalis coniferous and broadleaved mixed forest, or selecting Pinus tabulaeformis pure forest as the optimal silvicultural model.

The international non-tariff trade protection against China has gradually increased since 2018, hindering technology trade. Under the impact of the new trade protection, we still know little about how the electronic communication industry (as one of the strategic high-tech industries)changes the innovation cooperation relationship and the innovation performance. Owing to the failure of geographical research to integrate trade protection into the existing research framework from an institutional perspective, the trade protection literature and the innovation geography literature do not intersect. However, the trade geography literature has not paid enough attention to the evolution of industrial innovation in China in recent years and has not taken into account the heterogeneity of the industry-college-institute cooperation and innovation relationship and its impact on regional industrial innovation performance. Based on the 2014-2021 US Export Control Regulations and the invention patent data of the electronic communication industry in the Pearl River Delta, this study uses descriptive statistics, a Quadratic Assignment Procedure, and a negative binomial regression model. It explores both the mechanism and effect of a new round of trade protection on industry-college-institute cooperation and their joint impact on cooperative innovation performance. The study finds that the structure of the industry-college-institute cooperative innovation relationship in the electronic communication industry of the Pearl River Delta has gradually decentralized, and its heterogeneity growth tends to stall. The new round of trade protection significantly regulates geographical proximity, deteriorating the geographical scale of cooperative innovation. The regression results show that under the impact of trade protection, the heterogeneity of industry-college-institute cooperation changes from positive to negative, and the inverted U-shaped relationship has reached a significant level. Trade protection changes the influence of social and cognitive proximities and of geographical proximity on cooperative innovation performance, and the moderating effect of trade protection is highlighted by the positive effect of strengthening geographical proximity on industry-college-institute cooperation and innovation performance. The above findings remind us of the need to further refine and optimize innovation support policies. Therefore, the study puts forward some targeted policy suggestions, namely, to formulate innovation support policies suitable for the internal and externalized innovation transaction costs of different types of enterprises, strengthen the dominant role of enterprises in innovation, and promote cross-regional cooperation. To a certain extent, it can inform the decision-making by China's regional strategic industries around ending the international technology trade blockade and achieving high-quality independent innovation and technical cooperation.

“High-quality development” is an important objective for China’s current development projects. For the betterment of the current situation of the underdeveloped regions, high-quality development is necessary. The comprehensive index method is one of the most widely used methods for evaluating high-quality development works, and indicator weighting is its key and at the same time the most controversial step. Among many weighting methods, the entropy weighting method is widely applied due to its easier understandability and use. This article focuses on the problem of weight distortion when the entropy values of indicators are close to 1 and the improvements to this problem. To verify these improvements, this article deduces with mathematical analysis, the underlying assumptions of the problem and evaluates the level of high-quality development in Qinghai Province, which is assumed to be an appropriate example of the underdeveloped regions in western China. Our mathematical deductions demonstrate that these underlying assumptions do not theoretically exist. In addition, both the improved and the original methods have similar performances in practice or, more specifically, have shown an overall upward trend in the level of high-quality development in Qinghai Province. Because the “problem” is extremely stringent and difficult to reproduce, we conclude that further improvements on the entropy weighting method should not be a focus of future research. To address the subjectivity or objectivity issues of weighting, weightless methods may be of use and should be developed.

For low-carbon sustainability, recycled rubber particles (RPs) and recycled aggregate (RA) could be used to make rubber-modified recycled aggregate concrete (RRAC). The characteristics (compressive strength and peak strain) of RRAC with various amounts of RA and RPs after heating at various temperatures were studied in this work. The results show that high temperatures significantly decreased the uniaxial compressive strength (UCS), whereas the addition of RA (e.g., 50%) and RPs (e.g., 5%) can mitigate the negative effect caused by high temperatures. The peak strain can also be improved by increasing the replacement ratios of RA and RP. Support vector regression (SVR) models were trained using a total of 120 groups of UCS and peak strain experimental datasets, and an SVR-based multi-objective optimization model was proposed. The excellent correlation coefficients (0.9772 for UCS and 0.9412 for peak strain) found to illustrate the remarkable accuracy of the SVR models. The Pareto fronts of a tri-objective mixture optimization design (UCS, strain, and cost) were successfully generated as the decision reference at varying temperature conditions. A sensitivity analysis was performed to rank the importance of the input variables where temperature was found as the most important one. In addition, the replacement ratio of RA is more important compared with that of the RP for both the UCS and strain datasets. Among the mechanical properties of concrete, compressive strength and peak strain are two key properties. This study provides guidance for the study of RRAC constitutive models under high temperatures.

At present, the original drawing information of the substation is stored in a single way, and the degree of digital analysis is not high. In order to reduce the huge workload of manually analyzing the original drawing of the substation, a method is proposed to intelligently extract the information of the equipment and connection relationship of the substation based on the portable document format (PDF) drawing for building a physical circuit model, thus implementing the method according to the smart substation physical configuration description (SPCD) file. Firstly, the primitive information is extracted and processed from drawings. Then electrical symbol recognition is realized through string similarity matching running Karp-Rabin greedy string tiling (RKR-GST) algorithm, and substation images are classified by gradient boosting decision tree-logistic regression (GBDT-LR) hybrid algorithm based on features. Finally, the digital description from the original drawing to the physical circuit model is completed according to the SPCD file. Experiments show that the correct rate of electrical symbol matching is 93%, and the correct rate of physical circuit identification is more than 90% when there are errors in primitives.

This work presents the design and application of a low-cycle reciprocating loading test on 23 recycled aggregate concrete-filled steel tube columns and 3 ordinary concrete-filled steel tube columns. Additionally, a systematic study on the influence of various parameters (e.g., slenderness ratio, axial compression ratio, etc.) was conducted on the seismic performance of the specimens. The results show that all the specimens have good hysteresis performance and a similar development trend of skeleton curve. The influence of slenderness ratio on the seismic index of the specimens is more significant than that of the axial compression ratio and the steel pipe wall thickness. Furthermore, artificial intelligence was applied to estimate the influence of parameter variation on the seismic performance of concrete columns. Specifically, Random Forest with hyperparameters tuned by Firefly Algorithm was chosen. The high correlation coefficients (R) and low root mean square error values from the prediction results showed acceptable accuracy. In addition, sensitivity analysis was applied to rank the influence of the aforementioned input variables on the seismic performance of the specimens. The research results can provide experimental reference for the application of steel tube recycled concrete in earthquake areas.

Early childhood caries (ECC) is not only harmful to children's oral cavity and even the whole body, the government and relevant health departments pay more and more attention to the prevention and treatment of early childhood caries. However, at present, the primary treatment for ECC is the traditional filling therapy. The chronic disease management model can conduct regular testing of chronic non-communicable diseases and their risk factors, and provide long-term and effective professional management to patients by supervision and advice by doctors, nurses and pharmacists. This model has a good effect on slowing down the development of the disease, improving the quality of life of patients and saving public health resources. As a common chronic non-communicable disease, ECC is very suitable for prevention and treatment through chronic disease management. In recent years, chronic disease management models have also been increasingly used in the management of caries. The current common chronic disease management models include the chronic care model, innovative care for chronic condition, and British chronic disease management system models. And above models have certain applications in the management of ECC. How to establish the caries risk assessment system suitable for the diagnosis and treatment model of our country, and how to screen the children with high risk of caries by step-by-step prevention and control network for personalized prevention needed to be further studied in the future.

The dynamics of innovation in geographical space is closely related to the regional development trajectory. Evolutionary economic geography points out the path dependence characteristics of regional development, and emphasizes that the direction of regional development is rooted in the original industrial and technological structure characteristics. Therefore, the geographical pattern of technological innovation and the identification of its diversity characteristics are of significance to the realization of regional innovation and the evolution of industrial structure. From the perspective of strategic industry, this paper aims to reveal the geographical pattern and diversity characteristics of technological innovation in strategic industry in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). Based on the point scale spatial data of invention patents in the GBA and by means of connecting strategic industry with national economy industry classification code and patent IPC classification code, the invention patents of six major industries in the GBA are extracted, which are the new generation of electronic information industry, automobile industry, green petrochemical industry, new energy industry, advanced material industry and intelligent robot industry. And the nuclear density analysis, standard deviation tail value test, entropy method and average nearest neighbor distance analysis are used to identify the spatial distribution characteristics and differences of multiple types of technological innovation in the GBA. The results show that the geographic pattern of technological innovation in the GBA presents a significant spatial imbalance. At the regional scale, Guangzhou and Shenzhen are the two agglomeration cores. There is a large gap in the innovation ability between the east and west sides of the Pearl River. The accumulation of technological innovation on the east bank is much higher than that on the west bank. The innovation profile line on the east bank has formed two obvious peaks in Guangzhou and Shenzhen. The high value of the innovation profile line on the west bank is mainly concentrated in Guangzhou and Zhuhai, and the peak value is far lower than that on the east bank. The location of technological diversity is mainly distributed in the core areas of the GBA, mainly including Yuexiu District and Tianhe District in Guangzhou, Nanshan District and Futian District in Shenzhen, Binhai District in Dongguan and Xiangzhou District in Zhuhai. And the distribution characteristics of technological innovation data of different industrial types are different. The innovation of the new generation of electronic information industry, advanced materials industry and green petrochemical industry accounts for 51.67% of the total innovation in the GBA. The innovation of different technological types shows obvious spatial differentiation. The innovation agglomeration degree of the new generation electronic information industry is the highest, with the R value of 0.0576. And its observed value of the average nearest neighbor distance between invention patents is 32.03 m, which belongs to the minimum value in the selected analysis industries, showing strong agglomeration characteristics. There are differences in the distribution characteristics of the agglomeration core of the six major industries in the GBA. The common ground is that they have formed the largest two agglomeration cores in the core areas of Guangzhou and Shenzhen, covering Yuexiu-Tianhe area in Guangzhou and Futian-Nanshan-Luohu area in Shenzhen. And the spatial distribution is mainly concentrated in the core areas of Guangzhou, Shenzhen, Dongguan and Zhuhai. Among them, the spatial agglomeration degree of the new generation of electronic information industry innovation is the highest. Agglomeration and multi-dimensional proximity, diversity and path dependence are the main mechanisms for the formation of the geographical pattern of technological innovation in the GBA, and these two key mechanisms promote the formation of current multi-type technological innovation space in the GBA.

Regional coordinated development is a complex, systematic and scientific issue advancing with the time which has attracted much attention. The Guangdong-Hong Kong-Macao Greater Bay Area (GBA) aims to develop into a world-class bay area and urban agglomeration. The development of GBA depends on regional coordinated development to enhance its international competitiveness. At present, the process of globalization has experienced multiple turning points, the regional governance system has been continuously optimized, and the technological innovation has evolved rapidly. The coordinated development of the GBA is facing institutional changes. Therefore, through the systematic analysis of the connotations and mechanisms of the coordinated development of the GBA, this paper describes the three stages of regional coordinated development since 1978, including the integration of regional production factors represented by the ‘front shop, back factory’ mode (1978-1996), the regional system integration led by institutional cooperation (1997-2014), and the regional all-round integration guided by national strategy (2015- ). In the meantime, the paper analyzes the five dimensions of the coordinated development of the GBA in the new period, including industrial collaborative innovation, environmental collaborative governance, resource collaborative allocation, service collaborative sharing and institutional collaborative arrangement. These five dimensions are helpful to understand the key areas to promote the coordinated development of the GBA in the coming decades. Furthermore, this paper holds that the regional coordinated development of the GBA is undergoing mechanism changes at four levels, which are mainly reflected in the transformation of globalization, the integration of the internal and external market, the rescaling of governance, and the energization of regional in-depth development facilitated by the new infrastructure. These institutional changes have the potential to generate a new model for the coordinated development of the GBA. This paper takes into account the retrospective review and forward-looking prospect on the coordinated development of the GBA, aiming to provide an entry perspective and analysis framework for related issues.

Objective To investigate the effects of multi-oil fat emulsion injection on liver function, immune function and inflammation in intensive care unit (ICU) patients. Methods Eighty-four ICU patients admitted in the Department of Pulmonary and Critical Care Medicine of our hospital from June 2017 to September 2018 were prospectively recruited in this study. They were randomly divided into experimental group (n=42) and control group (n=42). The patients of both groups were given enteral nutrition+parenteral nutrition, and the fat emulsion was medium-long chain fat emulsion in the control group, and multi-oil fat emulsion in the experimental group. The energy and protein intake were basically similar in the patients of the 2 groups, and the nutritional support time was 7 days. Results The experimental group had significantly lower content of total bilirubin (22.2±5.5 vs 31.3±7.4 μmol/L, P < 0.05), increased counts of CD4 cells (442.3±31.4 vs 322.1±23.7, P < 0.05) and CD8 cells (289.7±23.4 vs 223.1±16.6, P < 0.05), and decreased levels of CRP (58.2±8.4 vs 83.7±17.1 mg/L, P < 0.05), IL-6 (36.9±5.2 vs 45.2±9.1 pg/mL, P < 0.05) and IL-8 (46.1±8.4 vs 53.7±9.5 pg/mL, P < 0.05) when compared with the control group. Conclusion Multi-oil fat emulsion injection enhances immune function, reduces inflammatory responses and attenuates liver damage (especially for cholestasis), and it is worthy of clinical promotion and application.

Achieved system level heterogeneous integration involving 130 nm tech node active Si interposer, two 65 nm tech node I/O chips and one 28 nm tech node FPGA die. Chip on Chip on Substrate packaging methodology was demonstrated for handling active Si interposer die as thin as 40 μm. Different packaging approaches were evaluated and the results are benchmarked. In addition, active Si interposer concept is introduced to provide Analog to Digital Converter (ADC), Digital to Analog Converter (DAC) and Power Management Unit (PMU) functions to support high-performance logic. Furthermore, benefits of active Si approach such as system scaling and cost-effectiveness have been demonstrated. “Via Last” TSV approach is used for the fabrication of 130 nm tech node active Si interposer. It was confirmed that appropriate selection of temporary bonding material plays a critical role in device wafer warpages in via last TSV process flow. Functionality checks were carried out on all samples subjected to preand post-reliability assessments, which include thermal cycling (TC), moisture sensitivity tests (MSL) and highly accelerated stress tests (HAST). All samples were found to be functional with no deterioration in performance despite being subjected to reliability tests and high-voltage stress tests.

Dissatisfaction is a major concept in power transition theory, which postulates that a rapidly rising power tends to be dissatisfied with the international system and would thus attempt to reform or replace it, whereas the hegemonic power would, by default, be satisfied with and work to maintain the status quo. This paper, however, offers an alternative outlook on the reigning-rising power dynamics by examining the conditions for and implications of hegemonic dissatisfaction and rising power satisfaction. It argues that although China, as a potential systemic challenger harboring grievances against the existing global regimes, has been a recurrent subject for studies, it is the United States, the established hegemon, that appears increasingly dissatisfied with the status quo. The U.S. dissatisfaction is informed by a set of internal and external factors often justified with a reference to China as a challenger, and is manifested in a number of anti-system strategies, including unconventional diplomatic rhetoric, as well as withdrawal from various international institutions or attempts to undermine them. The U.S. discontent, as contrasted with China’s satisfaction as a rising power, has a number of potential geopolitical and economic implications at the bilateral, regional, and global levels, endangering the viability and sustainability of the universally accepted political and economic regimes.

Dynamic stability is significantly important for flying quality evaluation and control system design of the advanced aircraft, and it should be considered in the initial aerodynamic design process. However, most of the conventional aerodynamic optimizations only focus on static performances and the dynamic motion has never been included. In this study, a new optimization method considering both dynamic stability and general lift-to-drag ratio performance has been developed. First, the longitudinal combined dynamic derivative based on the small amplitude oscillation method is calculated. Then, combined with the PSO (particle swarm optimization) algorithm, a dynamic stability derivative that must not be decreased is added to the constraints of optimization and the lift-drag ratio is chosen as the optimization objective. Finally, a new aerodynamic optimization method can be built. We take NACA0012 as an example to validate this method. The results show that the dynamic derivative calculation method is effective and conventional optimization design can significantly improve the lift-drag ratio. However, the dynamic stability is enormously changed at the same time. By contrast, the new optimization method can improve the lift-drag performance while maintaining the dynamic stability.

Radio-Frequency Interference (RFI) adversely affects useful signals, thereby seriously affecting image quality. In this study, a modified eigensubspace-based approach for radio-frequency interference suppression of Synthetic Aperture Radar (SAR) images is proposed. In the preprocessing stage of our proposed algorithm, RFI detection is conducted in both the frequency and time domains. Subsequently, we can only deal with the data containing the RFI via the traditional eigensubspace-based approach. Compared with the traditional eigensubspace-based approach, our proposed algorithm can function more efficiently and effectively.

To achieve high-resolution wide-swath imaging, the use of multichannel techniques in azimuth is effective for spaceborne Synthetic Aperture Radar (SAR). For azimuth multichannel systems, the signal in azimuth is nonuniformly sampled if the uniform sampling condition related to Pulse Repetition Frequency (PRF) is not satisfied, which makes it important to reconstruct the azimuth signal prior to image formation. In this study, to solve the azimuth signal reconstruction problem in multichannel SAR, we propose the innovative use of a multiframe super-resolution method in Digital Image Processing (DIP) and summarize the general multiframe super-resolution process. Our simulation results and real data experiments verify the effectiveness of the proposed method, which demonstrates some advantages in complexity performance. By establishing linkages between the problem of signal reconstruction of nonuniformly sampled signals and the multiframe superresolution concept, we provide a new approach to this traditional signal reconstruction problem.