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In this article, ZnO quantum dots (QDs)-g-C3N4 complexes were prepared by a combined sol–gel method and ultrasound-assisted chemical method, and ZnO-g-C3N4 composites with different doping ratios were also prepared for photocatalytic degradation of dye wastewater. The composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, Fourier transform infrared, X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy, and photoluminescence. The photocatalytic performance of the best ZnO QDs-g-C3N4 complexes with different g-C3N4 doping amounts was investigated, and the kinetics of their photocatalytic reactions were analyzed, and it was found that the best effect of ZnO-g-C3N4 10% could reach 89.08% and ZnO QDs-g-C3N4 could reach 91.53%. It was also demonstrated that ZnO-g-C3N4 10%, ZnO QDs-g-C3N4 cyclic stability is better, and the reaction mechanism of ZnO QDs-g-C3N4 was investigated. It can be used for the degradation of dyes in environmental wastewater and the removal of harmful substances from the natural environment.

Interest relationship is are the most basic among all social relations. In the field of urban renewal, the game process, conflict mechanism, and coordination mechanism among multiple stakeholders are important issues for cities to improve their sustainability. The stakeholders involved in the transformation of village-level industrial parks are more diverse, the interest differentiation is more frequent, and interest conflicts are more intense. The existing research mainly tries to explore the status quo, mode strategy and interest game in the transformation process of village industrial park from the aspects of power, system and space, and points out the importance of interest balance among "land stakeholders" such as government, market and property owners, but there are still deficiencies in the multi-subject participation mechanism and interest coordination mechanism. Due to the lack of advantages in location value, public finance and industry introduction, peripheral cities in the Pearl River Delta represented by Jiangmen are unable to ensure the positive guidance of spatial value remodeling and the full expression of diverse interests, resulting in slow progress of the reconstruction. Therefore, based on the stakeholder perspective of the urban regime theory, and constructing the multi-scale and multi-subject analytical framework of "stakeholder identification-interest conflict analysis-interest mechanism coordination,"the stakeholders in the upgrading of the village industrial park in Heshan City were investigated through a literature review, expert rating, and questionnaire interview. This study examines the practical problems of the village industrial park in Heshan City, Guangdong Province,to identify the stakeholders, interest demands, and conflicts involved in the transformation of the aforementioned. Subsequently, combined with typical park reconstruction cases, the interest game process of core stakeholders such as government departments, state-owned enterprises, private enterprises, financial institutions, village collectives, and villagers is discussed.Additionally, the evolutionary path and micro-mechanism framework of the formation of diversified interest alliances, the achievement of diversified goals, and the coordination of multi-subject interests are revealed in this process. Research shows the main constraints to the implementation of village-level industrial parks are the unequal power of stakeholders, unfair participation of power, unreasonable benefit distribution, and compensation mechanism. The participant-subjects and related capital input, source and income, collaborative transformation of industry and space, as well as the responsibility and power relationship of the implementation subject are more complex. In turn, government departments such as the Finance Bureau and the Bureau of Natural Resources are forced to form formal or informal partnerships with developers, enterprises and original owners. In the less developed areas of the Pearl River Delta, the mode of "government-led plusdiversified participation"is usually adopted. By entrusting full power to governmental financial organizations such as the Finance Bureau and the State-owned Assets Supervision and Administration Commission, village collectives and villagers are united with developers, operators, and financial institutions to form formal and informal cooperation relations, such as government-village and government-enterprise alliances, as well as interest distribution and incentive mechanisms. Additionally, the achievement of political, economic, social, and ecological diversification goals is promoted.Finally, this study proposes the following areas for future research: First, research on the micro behavior decision-making and mechanism of the village industrial park reconstruction can be conducted to further explore the "institutional space" of the reconstruction and its incentive and constraint mechanismto reveal the underlying"power-capital-space"and the political economic logic behind it. Second, against the background of multiple driving factors, there are also significant differences in the form, process, and mechanism of cooperation between the interest subjects of the village-level industrial park transformation. The differences in the main subjects in different modes, their temporal and spatial effects, and the mechanisms of action need to be further explored. Finally, the study investigates the social and cultural spatial response, governance path, and subject initiative of the village industrial park transformation, and reveals the possible ways in which village collectives and farmers' active social spatial practicescan improve their own situation through the logic of spatial governance.

The novel coronavirus disease 2019 (COVID-19), which spread all over the world at the beginning of 2020, exerted significant impacts on the substantial economic and social development in China, seriously affecting the production and operation of Chinese small and medium-sized enterprises (SMEs). As the COVID-19 pandemic was effectively controlled by the central government, China's economy manifested strong economic resilience during the process of recovery. Under these circumstances, it provided a valuable opportunity to examine the dynamic evolution and mechanism of economic resilience over a relatively short period. In economic geography research, structure and agency are the two main influencing factors for regional economic resilience; specifically, structural factors refer to the economic diversity and inherited structure of a regional economy in building resilience capacities, while agency factors focus on the role of agentsin a resilient economic system. However, the existing literature has focused heavily on structural factors, but the effect of agency factors has gained less attention. Based on interviews with 43 manufacturing SMEs in Dongguan in 2020, this study 1) investigates the dynamic evolution and characteristics of short-term economic resilience from an agency perspective and 2) demonstrates the micro-mechanism of reconstructing economic resilience at the enterprise level by constructing a structure-agency framework. The study derives several findings. First, economic resilience is not an inherent attribute of an economic agent. In the short term, the formation of economic resilience can be divided into a three stage process from cognition to adaptation, and then to reconstruction. Each stage manifests different agency characteristics. Second, the reconstruction of economic resilience is strongly influenced by the individual (entrepreneurs) and collective agency (supplies and customers) in the COVID-19 shock. For individual agencies, manufacturing SMEs are sensitive to perceiving and seizing the "opportunity space," which is technologically related to their primary products. For collective agency, many entrepreneurs actively offer financial support to their upper and lower reach enterprises to enhance economic resilience by forming collective networks. Third, structural factors (i.e., industrial structure, institutional arrangement, and infrastructure construction) also influence the formation of economic resilience in a short period. In the case of Dongguan, industrial structure and institutional arrangements contributed to enterprises' return to normal production during the COVID-19 crisis, while the imbalance of infrastructure structures (including basic social and public services) plays a constrained role in economic resilience. Moreover, three theoretical implications are proposed: emphasizing the transformation between short-term adaptation and long-term adaptability, concerning the shaping of structural factors caused by agency, and paying attention to the coupling between agents and external connections.

Study Design: Retrospective study. Objective: Lumbar magnetic resonance imaging (MRI) findings are believed to be associated with low back pain (LBP). This study sought to develop a new predictive classification system for low back pain. Method: Normal subjects with repeated lumbar MRI scans were retrospectively enrolled. A new classification system, based on the radiological features on MRI, was developed using an unsupervised clustering method. Results: One hundred and fifty-nine subjects were included. Three distinguishable clusters were identified with unsupervised clustering that were significantly correlated with LBP (P =.017). The incidence of LBP was highest in cluster 3 (57.14%), nearly twice the incidence in cluster 1 (30.11%). There were obvious differences in the sagittal parameters among the 3 clusters. Cluster 3 had the smallest intervertebral height. Based on follow-up findings, 27% of subjects changed clusters. More subjects changed from cluster 1 to clusters 2 or 3 (14.5%) than changed from cluster 2 or cluster 3 to cluster 1 (5%). Participation in sport was more frequent in subjects who changed from cluster 3 to cluster 1. Conclusion: Using an unsupervised clustering method, we developed a new classification system comprising 3 clusters, which were significantly correlated with LBP. The prediction of LBP is independent of age and better than that based on individual sagittal parameters derived from MRI. A change in cluster during follow-up may partially predict lumbar degeneration. This study provides a new system for the prediction of LBP that should be useful for its diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Yersinia pestis has been historically divided into three biovars: antiqua, mediaevalis, and orientalis. On the basis of this study, strains from Microtus-related plague foci are proposed to constitute a new biovar, microtus. Based on the ability to ferment glycerol and arabinose and to reduce nitrate, Y. pestis strains can be assigned to one of four biovars: antiqua (glycerol positive, arabinose positive, and nitrate positive), mediaevalis (glycerol positive, arabinose positive, and nitrate negative), orientalis (glycerol negative, arabinose positive, and nitrate positive), and microtus (glycerol positive, arabinose negative, and nitrate negative). A 93-bp in-frame deletion in glpD gene results in the glycerol-negative characteristic of biovar orientalis strains. Two kinds of point mutations in the napA gene may cause the nitrate reduction-negative characteristic in biovars mediaevalis and microtus, respectively. A 122-bp frameshift deletion in the araC gene may lead to the arabinose-negative phenotype of biovar microtus strains. Biovar microtus strains have a unique genomic profile of gene loss and pseudogene distribution, which most likely accounts for the human attenuation of this new biovar. Focused, hypothesis-based investigations on these specific genes will help delineate the determinants that enable this deadly pathogen to be virulent to humans and give insight into the evolution of Y. pestis and plague pathogenesis. Moreover, there may be the implications for development of biovar microtus strains as a potential vaccine.

Genomics research provides an unprecedented opportunity for us to probe into the pathogenicity and evolution of the world's most deadly pathogenic bacterium, Yersinia pestis, in minute detail. In our present work, extensive microarray analysis in conjunction with PCR validation revealed that there are considerable genome dynamics, due to gene acquisition and loss, in natural populations of Y. pestis. We established a genomotyping system to group homologous isolates of Y. pestis, based on profiling or gene acquisition and loss in their genomes, and then drew an outline of parallel microevolution of the Y. pestis genome. The acquisition of a number of genomic islands and plasmids most likely induced Y. pestis to evolve rapidly from Yersinia pseudotuberculosis to a new, deadly pathogen. Horizontal gene acquisition also plays a key role in the dramatic evolutionary segregation of Y. pestis lineages (biovars and genomovars). In contrast to selective genome expansion by gene acquisition, genome reduction occurs in Y. pestis through the loss of DNA regions. We also theorized about the links between niche adaptation and genome microevolution. The transmission, colonization, and expansion of Y. pestis in the natural foci of endemic plague are parallel and directional and involve gradual adaptation to the complex of interactions between the environment, the hosts, and the pathogen itself. These adaptations are based on the natural selections against the accumulation of genetic changes within genome. Our data strongly support that the modern plague originated from Yunnan Province in China, due to the arising of biovar orientalis from biovar antiqua rather than mediaevalis.

Genomics provides an unprecedented opportunity to probe in minute detail into the genomes of the world's most deadly pathogenic bacteria-Yersinia pestis. Here we report the complete genome sequence of Y. pestis strain 91001, a human-avirulent strain isolated from the rodent Brandt's vole-Microtus brandti. The genome of strain 91001 consists of one chromosome and four plasmids (pPCP1, pCD1, pMT1 and pCRY). The 9609-bp pPCP1 plasmid of strain 91001 is almost identical to the counterparts from reference strains (CO92 and KIM). There are 98 genes in the 70,159-bp range of plasmid pCD1. The 106,642-bp plasmid pMT1 has slightly different architecture compared with the reference ones. pCRY is a novel plasmid discovered in this work. It is 21,742 bp long and harbors a cryptic type IV secretory system. The chromosome of 91001 is 4,595,065 bp in length. Among the 4037 predicted genes, 141 are possible pseudogenes. Due to the rearrangements mediated by insertion elements, the structure of the 91001 chromosome shows dramatic differences compared with CO92 and KIM. Based on the analysis of plasmids and chromosome architectures, pseudogene distribution, nitrate reduction negative mechanism and gene comparison, we conclude that strain 91001 and other strains isolated from M. brandti might have evolved from ancestral Y. pestis in a different lineage. The large genome fragment deletions in the 91001 chromosome and some pseudogenes may contribute to its unique nonpathogenicity to humans and host-specificity. [ABSTRACT FROM PUBLISHER]

The location selection mechanism and effect of industrial transfer have been widely considered in academia, but the influence of institutional factors on cross-regional industrial transfer and regional differences still need further investigation. Based on theories of economic geography as well as new economic geography (NEG) and its' institutional transformation, this paper studies the form, mechanism, and effect of the "core–periphery" regional relationship between the Pearl River Delta (PRD) and non-Pearl River Delta (NPRD) areas in Guangdong Province from the micro perspective of industrial spatial organization. Based on a case study on the change of the cross-regional production spatial organization of ceramics enterprises between Foshan and Qingyuan, it is found that after three rounds of spatial reorganization, the production spatial organization of Foshan's and Qingyuan's ceramics industries has changed significantly, forming a multifactory, multilocation production spatial structure and regional production network, which further drives to form the regional functional division of "core–periphery". Institution factors, especially environmental regulation and industrial transfer institutional arrangements, have become an important driving force for the current industrial transfer, but its impact on regional relations is still not a decisive factor. The path locking of the "core–periphery" mode has not been fundamentally broken through. Although the form of spatial inequality has greatly changed, in fact, it produces a new form of inequality. The economic, geographical, and political theoretical framework from the micro-perspective of enterprises will provide a possible theoretical explanation for the phenomenon of "pollution moving to the West, high-tech industry moving to the East, industrial output gathering to the East" in China. [ABSTRACT FROM AUTHOR]